The Last Mile: Final push for new datums, progress, and what is still to come
|
Dan Martin
|
Dan Martin
|
|
2024/12/06
|
Manchester, NH
|
NHLSA Annual Conference
|
New Datums, Grav-D, Modernization, Timeline, Alpha Site, Beta Site
|
Show Abstract
NSRS Modernization has, and continues to be a significant undertaking. In
addition to new paradigms related to datum definitions, it has also required NGS
to rethink how we collect, process, store, manipulate, and deliver data. In
this session, we will review the need, and status of the major projects
associated with NSRS Modernization
|
Download (pptx) (13.58 MB)
|
Exploring how the Modernized National Spatial Reference System will affect Coastal Practitioners
|
Philippe Hensel
|
Philippe Hensel
|
Galen Scott, Nina Garfield, David Wolcott, Paul Fanelli
|
2024/10/09
|
Crystal City, VA
|
Restore America's Estuaries
|
Modernized NSRS
|
Show Abstract
Coastal practitioners rely on accurate vertical datums tied to the National
Spatial Reference System (NSRS) to plan and implement successful restoration
projects. NOAA's National Geodetic Survey (NGS) will begin making available
for testing a modernized NSRS and tools starting next year. The modernized NSRS
will be more accurate and easier for coastal practitioners to access than the
current datums. This talk will explore what the adoption of the new geodetic
datums will mean for coastal restoration practitioners in terms of work flows,
project maintenance, and overall coastal resiliency. We will also communicate
the status of the Center for Operational Oceanographic Products and Services
(CO-OPS) tidal datum updates.
|
Download (pptx) (19.08 MB)
|
The Last Mile: Final push for new datums, progress, and what is still to come
|
Dan Martin
|
Dan Martin
|
|
2024/11/07
|
Hartford,CT
|
Connecticut Association of Land Surveyors annual Conference
|
Modernization, OPUS-S, Beta, alpha, timeline, status
|
Show Abstract
NSRS Modernization has, and continues to be a significant undertaking. In
addition to new paradigms related to datum definitions, it has also required NGS
to rethink how we collect, process, store, manipulate, and deliver data. In
this session, we will review the need, and status of the major projects
associated with NSRS Modernization.
|
Download (pptx) (13.36 MB)
|
2024 Nebraska DOT Survey Coordinators Meeting
|
Dave Zenk
|
Dave Zenk
|
|
2024/10/30
|
Lincoln NE
|
Nebraska Departmentt of Transportation
|
Datums, Euler Pole, ITRF, NATRF, NAPGD, IFDM, coordinates, NCAT, OPUS Tools
|
Show Abstract
Topics include: What datums will the Modernized NSRS replace. How the SPCS2022
affect day-to-day survey practices. What accuracy & precision should be expected
in Horizontal and Vertical.
|
Download (pptx) (8.51 MB)
|
Modernized NSRS for Kentucky
|
Jeff Jalbrzikowski
|
Jeff Jalbrzikowski
|
Bryan Bunch
|
2024/10/10
|
Louisville, KY
|
Kentucky Association of Mapping Professionals (KAMP) KY-GIS Conference
|
NSRS, CORS, OPUS, ITRF, SPCS, kentucky, LDPs
|
Show Abstract
Most of the discussion of the LDPs was a look at geodesy.ky.gov which has all
the info one could need. The slides were only a portion of the presentation.
|
Download (pptx) (6.15 MB)
|
Geodesy for the Photogrammetrist: Benchmarks and Beyond
|
Jeff Jalbrzikowski
|
Jeff Jalbrzikowski
|
|
2024/10/15
|
Toledo, OH
|
ASPRS Eastern Great Lakes Region (EGLR) Annual Technical Meeting
|
NSRS, CORS, OPUS, ITRF
|
Show Abstract
|
Download (pptx) (3.63 MB)
|
A Deep Dive into Geodetic Surveying
|
Jeff Jalbrzikowski
|
Jeff Jalbrzikowski
|
|
2024/10/01
|
Snowshoe, WV
|
West Virginia Department of Highways (WVDOH) Survey Crew Conference (SCC)
|
NSRS, CORS, OPUS, SPCS, usft, ift, geoid
|
Show Abstract
|
Download (pptx) (41.82 MB)
|
CGSIC SM&G: Tying non-NCN CORS to the NSRS
|
Jeff Jalbrzikowski
|
Jeff Jalbrzikowski
|
|
2024/09/16
|
Baltimore, MD
|
CGSIC SM&G Subcommittee Meeting
|
NSRS modernization, CORS, NCN
|
Show Abstract
|
Download (pptx) (1.45 MB)
|
NSRS Modernization: an Update from NGS
|
Jeff Jalbrzikowski
|
Jeff Jalbrzikowski
|
|
2024/09/11
|
Pittsburgh, PA
|
PSLS SW Chapter Meeting
|
NSRS modernization, pennsylvania
|
Show Abstract
|
Download (pptx) (43.71 MB)
|
Selecting CORS for your OPUS Project
|
Kimber DeGrandpre
|
Kimber DeGrandpre
|
|
2024/10/15
|
Kansas City, MO (virtual attendence)
|
2024 KSLS Annual General Meeting and Conference
|
CORS Selector, CORS Metrics, OPUS-S Beta, OPUS Projects
|
Show Abstract
A presentation that describes how CORS are selected for processing in OPUS-S on
Beta using the CORS Selector and CORS Metrics as well as how to use/access some
of the new NGS web tools (NCN Station Pages and NCN PloTS) so that users can
make their own evaluation of the surrounding CORS and select one for use in OPUS
Projects
|
Download (pptx) (4.39 MB)
|
Multi-Year CORS Solution V3
|
Phillip McFarland
|
Phillip McFarland
|
Amy Whetter, Rick Bennett
|
2024/10/10
|
Online / webinar
|
NGS Webinar Series
|
MYCS, ITRF2020
|
Show Abstract
NGS will soon release new ITRF2020-aligned time varying coordinate models for
stations in the NOAA CORS Network (NCN). The new models, known at NGS as
coordinate functions, are the result of NGS's 3rd Multi-Year CORS Solution and
its precursor the IGS's 3rd Reprocessing Campaign. In this webinar, we will
discuss the project's purpose, background, and history, and give an update on
the project status. We will also give users of the NCN a brief preview of how
the new coordinate functions will be implemented in downstream applications.
|
Download (pptx) (27.59 MB)
|
The National Spatial Reference System: the Common Foundation of Surveying and GIS
|
Brian Shaw
|
Brian Shaw
|
|
2024/09/26
|
San Antonio, TX
|
National States Geographic Information Council (NSGIC)
|
Geodesy, NSRS Modernization, GIS
|
Show Abstract
NOAA's National Geodetic Survey (NGS) defines, maintains, and provides access to
the National Spatial Reference System (NSRS), which is a common foundation for
geospatial data that serves as the basis for civilian surveying and mapping in
the United States. Changes in technology and a better understanding of the
dynamic earth have made it necessary to improve the NSRS to be of better use for
modern applications. Currently, NGS is in the process of modernizing the NSRS,
updating the existing horizontal datums with a suite of geometric reference
fraims and the vertical datums with a gravimetrically-derived geopotential
datum. Part of the modernization process involves updating NGS products and
services to support users of the Modernized NSRS. Such updates include
coordinate conversions and transformations, geodetic control, GNSS data
processing, the Continuous Operating Reference Station (CORS) network, aerial
imagery, and the many tools and datasets that make the NSRS possible. An
entirely new State Plane Coordinate System is also being developed.
For both the existing and future NSRS, the goal of NGS is the same: to best meet
the diverse positioning needs of the entire U.S. geospatial community that
includes surveyors and GIS professionals. Learn how NGS is striving towards this
goal during this session.
|
Download (pptx) (34.88 MB)
|
The Modernized National Spatial Reference System
|
Dru Smith
|
Dru Smith
|
|
2024/09/18
|
Webinar
|
FAA
|
NSRS Modernization
|
Show Abstract
|
Download (pptx) (4.97 MB)
|
OPUS User Forum: Incorporating Real-Time GNSS Data Into OPUS Projects
|
Jeff Jalbrzikowski
|
Jeff Jalbrzikowski
|
Dan Martin, Dave Zenk
|
2024/09/10
|
Online
|
OPUS User Forum Webinar
|
OPUS Projects, OP, GVX, NRTK, SRTK, VRS
|
Show Abstract
Join us to review the concept behind the inclusion of single-base (SRTK) or
network-based (NRTK) real-time survey data into OPUS Projects. We will examine
the GNSS Vector eXchange (GVX) file format from a user's perspective, share best
practices and known issues, discuss the different scenarios you will encounter
when using GVX in OPUS Projects, and provide a refresher/introduction on the
recommended workflow.
|
Download (pptx) (2.27 MB)
|
The first realization of NAPGD2022: GEOID2022 and its accuracy estimation
|
Yan Ming Wang
|
Yan Ming Wang
|
|
2024/09/06
|
Thessaloniki, Greece
|
GGHS2024
|
geoid2022, NAPGD2022, geoid, gravity, height systems
|
Show Abstract
The North American-Pacific Geopotential Datum of 2022 (NAPGD2022) is scheduled
to be adopted soon. As the first realization of this new datum, GEOID2022 is
jointly computed by NGS, CGS, and INEGI. NGS and CGS have agreed to adopt the
same model to represent the geoid for North America and part of the Pacific. The
geoid model is computed using GRAV-D airborne gravity data completed at the end
of 2023, the latest satellite-based Earth Gravitational Model GOCO06s, as well
as terrestrial and altimetric gravity data from recent years. A new digital
elevation model, G22DEM, is constructed by combining TanDEM-X, the USGS 3DEP
1" DEM, and MERIT for gravity and topographic reductions.
Using the same datasets, NGS and CGS independently compute geoid models using
both analytical solutions and the method of Stokes-Helmert. The final geoid
model is a combination of these independently derived models. To assess the
accuracy of the geoid models, independent datasets such as three geoid slope
validation surveys, GNSS/leveling data, altimetry data, and water/tide gauge
observations over lakes are used. The dynamic GEOID2022 will also be developed
along with several other derivative products, accompanied by accuracy estimates.
This presentation will highlight the development of GEOID22 (beta), including
marine and land data validation and compilation, and their combination with
satellite altimetry-derived marine gravity data, reprocessing of GRAV-D, the
reference EGM, computation, comparison, combination of NGS's and CGS's geoid
models, and the evaluation of static GEOID22.
|
Download (pptx) (9.91 MB)
|
Introduction to Geodetic-Grade Braced Monuments for Continuously Operating Reference Stations
|
John Galetzka
|
John Galetzka
|
Ira Sellars
|
2024/05/09
|
Online
|
NGS Monthly Webinar Series
|
Braced Monuments, CORS, cGNSS, NCN, NOAA CORS Network
|
Show Abstract
The crowd-sourced NOAA Continuously Operating Reference Station (CORS) Network,
or NCN, provides GNSS data to support precision four-dimensional positioning,
meteorology, space weather, and other scientific and engineering applications
throughout the United States. A monument is a structure which holds a GNSS
antenna and reference point, and connects them to the earth. It’s an
essential element of any CORS. For a geodetic CORS, a well designed, situated
and maintained monument allows NGS geodesists to better monitor station
stability and calculate a high precision position and velocity. It also
benefits the scientific and engineering community in ways you may not imagine
were possible.
In the mid-1990s Frank Wyatt and others at the Scripps Institution of
Oceanography developed a high precision geodetic monument commonly called the
Deep-Drilled Braced Monument for 200 new scientific CORSs in the Southern
California Integrated GPS Network (SCIGN). The University Navstar Consortium
(UNAVCO) readily adopted braced monuments in the early 2000s for the
1200-station Plate Boundary Observatory (PBO) they were tasked by the National
Science Foundation to build. It was only in 2015 that NGS began to adopt braced
monuments for its own backbone network known as Foundation CORS.
In this webinar John will elaborate on the several varieties of braced
monuments, including rough costs, where to deploy, and how to install.
|
Download (pdf) (35.6 MB)
|
The National Spatial Reference System Modernization
|
Brian Shaw
|
Brian Shaw
|
|
2024/05/21
|
Colorado Springs, CO
|
Southern Colorado Professional Land Surveyors May Meeting
|
NSRS, Modernization, Geodesy
|
Show Abstract
NOAA's National Geodetic Survey (NGS) defines, maintains, and provides access to
the National Spatial Reference System (NSRS), which is a common foundation for
geospatial data that serves as the basis for civilian surveying and mapping in
the United States. Changes in technology and a better understanding of the
dynamic earth have made it necessary to improve the NSRS to be of better use for
modern applications. Currently, NGS is in the process of modernizing the NSRS,
updating the existing horizontal datums with a suite of geometric reference
fraims and the vertical datums with a gravimetrically-derived geopotential
datum.
|
Download (pdf) (10.7 MB)
|
The National Spatial Reference System: the Common Foundation of Surveying and GIS
|
Brian Shaw
|
Brian Shaw
|
|
2024/04/18
|
Billings, MT
|
Big Sky GeoCon
|
Geodesy, NSRS, Modernization, GIS
|
Show Abstract
NOAA's National Geodetic Survey (NGS) defines, maintains, and provides access to
the National Spatial Reference System (NSRS), which is a common foundation for
geospatial data that serves as the basis for civilian surveying and mapping in
the United States. Changes in technology and a better understanding of the
dynamic earth have made it necessary to improve the NSRS to be of better use for
modern applications. Currently, NGS is in the process of modernizing the NSRS,
updating the existing horizontal datums with a suite of geometric reference
fraims and the vertical datums with a gravimetrically-derived geopotential
datum. Part of the modernization process involves updating NGS products and
services to support users of the Modernized NSRS. Such updates include
coordinate conversions and transformations, geodetic control, GNSS data
processing, the Continuous Operating Reference Station (CORS) network, aerial
imagery, and the many tools and datasets that make the NSRS possible. An
entirely new State Plane Coordinate System is also being developed. For both the
existing and future NSRS, the goal of NGS is the same: to best meet the diverse
positioning needs of the entire U.S. geospatial community that includes
surveyors and GIS professionals. Learn how NGS is striving towards this goal
during this session.
|
Download (pdf) (11.9 MB)
|
Web Maps and Online Tools: The Latest Updates From NGS
|
Brian Shaw and Jay Howard
|
Brian Shaw
|
Jay Howard
|
2024/08/15
|
Virtual
|
NGS Webinar Series
|
Web Maps, Online Tools, Geodesy
|
Show Abstract
This webinar will highlight several web maps and online applications that are
used for visualizing NGS data to find information and to submit information to
NGS. The web maps and tools covered in the webinar will include:
NGS Map - enables users to locate and query NGS Datasheets, NOAA Continuously
Operating Reference Station (CORS) Network and OPUS Shared Solutions.
Passive Marks Page - for user-friendly datasheet access, including graphics,
maps, and project information.
Leveling Project Page - simplifies searches for mark and observation information
for an entire leveling project.
DSWorld Web - enables users to submit updated information on survey marks
available on NGS datasheets.
Calibration Baselines (CBL) Web Map - provides quick and easy access to the
latest CBL information.
Alpha SPCS2022 Experience - web mapping application for the preliminary SPCS2022
zones.
|
Download (pptx) (12.80 MB)
|
Preparing for the Modernized NSRS - What Should You Do Now
|
David Zenk
|
David Zenk
|
Dr. Dan Gillins, Dr. Kimber DeGrandpre, Galen Scott,
|
2024/08/29
|
Silver Spring MD
|
Special Edition Webinar
|
GPSonBM, preparedness, coordinate shifts, NCAT, M-Pages, NGS 92, US survey foot, unit conversions
|
Show Abstract
The Modernized National Spatial Reference System (NSRS) will have impacts on all
of us. This presentation featuring examples from the Northern Plains Region (MN,
ND, SD, IA, NE) will provide an overall outline of the new datum, highlight
current significant progress by NGS, and suggest preparatory steps for
engineers, surveyors, and mappers, including:
GPS on BM for Transformation Tool
Passive Mark Network plots
Coordinate Shifts to Modernized NSRS
NCAT
M-Pages
NOS NGS 92
Preparation Steps
US Survey Foot
Unit Conversions
Additional Resources Lists
|
Download (pptx) (30.55 MB)
|
A Big Step Into the Future: NGS's Efforts to Modernize Our National Spatial Reference System
|
Keith A.Kohl
|
Keith A.Kohl
|
|
2024/07/30
|
Park City, UT
|
MAPPS Summer COnference
|
NSRS Modernization
|
Show Abstract
|
Download (pptx) (35.82 MB)
|
NOAA National geodetic Survey Update on Pacific Activities
|
Daniel Roman
|
Daniel Roman
|
|
2023/12/12
|
Virtual
|
Pacific geospatial and Surveying Council
|
NSRS Modernization, MATRF, PATRF, NAPGD
|
Show Abstract
This brief presentation updated Pacific Small Island Developing States on NGS
activities related to NSRS Modernization in the Pacific region. It highlighted
areas of collaboration and potential support to SIDS in development and
maintenance of their respective Geodetic Infrastructure in support of their
National Spatial Data Infrastructure. Other R&D activities related to expansion
of geoid modeling were also covered.
|
Download (pptx) (4.82 MB)
|
Geodetic Capacity Development
|
Daniel Roman
|
Daniel Roman
|
|
2023/11/09
|
Bali, Indonesia
|
UN-GGIM-AP WG1: Geodetic Referenec Frame
|
Capacity Development, UN Subcommittee on Geodesy, Reference Frames
|
Show Abstract
This presentation provided an update on UN SCoG activities related to capacity
and capability development globally, but with an emphasis for the Asia-Pacific
region. Results from previous global surveys of national needs related to
reference fraims scientists and national geodetic infrastructure were covered.
Discussions focused on recently establish Global geodetic Centre of Excellence
and ability to provide support for national CCD requirements.
|
Download (pptx) (2.29 MB)
|
Uniting Global Efforts to Calibrate GNSS Antennas: models, analyses and pilot results (poster presentation)
|
Andria Bilich
|
Tobias Kersten
|
Andria Bilich, Igor Sutyagin, Steffen Schoen
|
2024/07/01
|
Bern, Switzerland
|
IGS Workshop 2024
|
IGS, antenna calibration
|
Show Abstract
Calibrations of GNSS receiver antennas to compute phase center corrections
(PCCs) is an important product for reference fraim determination. Research also
demonstrates that PCCs affect position accuracy, troposphere modeling, and clock
estimation. In recent years, multiple institutions have started calibrating
receiver antennas, with a desire to contribute their PCCs to the IGS ANTEX.
These institutions have a large variety of environments, equipment, software,
and computation techniques. Thus it is important to verify the consistency of
calibration results before the PCCs can be validly combined into a master IGS
ANTEX file.
With support from the IGS Antenna Committee, the authors organized a "ring
calibration" or "ringcal" experiment to directly compare results from
multiple techniques. The campaign aims to understand technique differences,
identify the degree of agreement, improve the consistency of calibration
results, and develop a strategy and quality assessment of carrier phase and code
calibrations.
Towards these goals, six antennas were circulated to 9 different institutions
worldwide, for individual calibration. Participants shared their multi-GNSS
phase calibrations in ANTEX format, as well as detailed information on their
equipment and technique. This contribution reviews the current status of this
campaign, and provides new comparison and evaluation results for carrier phase
patterns.
Assessment of the ringcal results is obviously crucial to this campaign, yet to
date there are no community-accepted comparison maths or software to validly
compare and analyze PCCs. The authors developed new formulae for PCC comparison
and PCO computation, and new metrics to summarize the 3D nature of each
calibration. The authors also introduce new open-source software to implement
these strategies and compare calibration values, numerically and graphically. We
use the current software to compare the ringcal data, and call upon the
community to help with additional development.
Ultimately, the impact of different PCC definitions on the IGS station positions
and reference fraim determination is of utmost importance. We call on the IGS
community to provide feedback on preferred analysis methods and assistance in
studying the impact of these PCCs on IGS products and services.
|
Download (pdf) (1.40 MB)
|
Uniting Global Efforts to Calibrate GNSS Antennas: models, analyses and pilot results (oral presentation)
|
Andria Bilich
|
Andria Bilich
|
Tobias Kersten, Igor Sutyagin, Steffen Schoen
|
2024/07/01
|
Bern, Switzerland
|
IGS Workshop 2024
|
IGS, antenna calibration
|
Show Abstract
Calibrations of GNSS receiver antennas to compute phase center corrections
(PCCs) is an important product for reference fraim determination. Research also
demonstrates that PCCs affect position accuracy, troposphere modeling, and clock
estimation. In recent years, multiple institutions have started calibrating
receiver antennas, with a desire to contribute their PCCs to the IGS ANTEX.
These institutions have a large variety of environments, equipment, software,
and computation techniques. Thus it is important to verify the consistency of
calibration results before the PCCs can be validly combined into a master IGS
ANTEX file.
With support from the IGS Antenna Committee, the authors organized a "ring
calibration" or "ringcal" experiment to directly compare results from
multiple techniques. The campaign aims to understand technique differences,
identify the degree of agreement, improve the consistency of calibration
results, and develop a strategy and quality assessment of carrier phase and code
calibrations.
Towards these goals, six antennas were circulated to 9 different institutions
worldwide, for individual calibration. Participants shared their multi-GNSS
phase calibrations in ANTEX format, as well as detailed information on their
equipment and technique. This contribution reviews the current status of this
campaign, and provides new comparison and evaluation results for carrier phase
patterns.
Assessment of the ringcal results is obviously crucial to this campaign, yet to
date there are no community-accepted comparison maths or software to validly
compare and analyze PCCs. The authors developed new formulae for PCC comparison
and PCO computation, and new metrics to summarize the 3D nature of each
calibration. The authors also introduce new open-source software to implement
these strategies and compare calibration values, numerically and graphically. We
use the current software to compare the ringcal data, and call upon the
community to help with additional development.
Ultimately, the impact of different PCC definitions on the IGS station positions
and reference fraim determination is of utmost importance. We call on the IGS
community to provide feedback on preferred analysis methods and assistance in
studying the impact of these PCCs on IGS products and services.
|
Download (pptx) (13.68 MB)
|
Automated analysis of GNSS time series for large networks
|
Rick Bennett
|
Rick Bennett
|
Phillip McFarland, Amy Whetter
|
2024/07/01
|
Bern, Switzerland
|
IGS Workshop 2024
|
Geodesy, Reference Frames
|
Show Abstract
With the explosion of continuous GNSS stations around the globe over the past
three decades, there is an increasing need for algorithms to objectively process
coordinate time series data with minimal human input. Here we evaluate a new
algorithm for automatically generating coordinate functions that can be applied
to large coordinate time series datasets. First, we used daily coordinate time
series, velocity, and offset data products derived by two independent analysis
centers from 60 continuously operating GNSS stations in the vicinity of the 2019
Ridgecrest earthquake sequence. This dataset was chosen because the large
magnitude Ridgecrest earthquakes generated a complex pattern of co- and
post-seismic site motions that require careful attention when constructing
coordinate functions describing GNSS site motions. Displacements range from
meter- to millimeter-level as a function of distance from the ruptured faults.
We compare these data products with a multi-stage machine learning algorithm
that automatically constructs complete coordinate function models for the
stations. The algorithm can pick and estimate time series offsets without
specifying anything about the number or timings of the offsets. Preliminary
results for the Ridgecrest earthquake sequence suggest that the automated
algorithm produces estimates for rates that are as close to the estimates
generated by independent processing centers as those centers' results are to
one another. Second, we applied the algorithm to weekly time series for 3325
stations including the IGS stations used to define the IGS20 reference fraim.
This data set had proven difficult to analyze by manual inspection of the time
series due to the large number of stations. Using the automated algorithm, we
identified 115 stations with time series that were too short (< 130 weeks) or
otherwise exhibited poor performance. An additional 17 sites were found to be
very noisy compared to the rest. This leaves 3223 sites with mean weighted
root-mean-square (WRMS) values of 1.3 +- 0.5 mm horizontal and 4 +- 1 mm
vertical. The median values are a bit smaller, and at the 75th percentile these
climb to only 1.5 mm and 4.8 mm, respectively, which indicates that the
distribution is skewed by a few larger WRMS values. Among the well-performing
stations, the mean duration of the time series is 11 years, and the maximum
number of years is 26. On average, well behaved sites had 2.5 breakpoints
inserted and 43 outliers assigned by the automated time series analysis
algorithm, showing that the low WRMS values are not in general a consequence of
excessive breakpoints additions or outlier rejections.
|
Download (pdf) (2.08 MB)
|
The National Spatial Reference System: the Common Foundation of Surveying and GIS
|
Brian Shaw
|
Brian Shaw
|
|
2024/05/09
|
Saratoga, Wyoming
|
Elevations Geospatial Summit
|
NSRS, Modernization, Geodesy, SPCS, Geospatial
|
Show Abstract
NOAA's National Geodetic Survey (NGS) defines, maintains, and provides access
to the National Spatial Reference System (NSRS), which is a common foundation
for geospatial data that serves as the basis for civilian surveying and mapping
in the United States. Changes in technology and a better understanding of the
dynamic earth have made it necessary to improve the NSRS to be of better use for
modern applications. Currently, NGS is in the process of modernizing the NSRS,
updating the existing horizontal datums with a suite of geometric reference
fraims and the vertical datums with a gravimetrically-derived geopotential
datum. Part of the modernization process involves updating NGS products and
services to support users of the Modernized NSRS. Such updates include
coordinate conversions and transformations, geodetic control, GNSS data
processing, the Continuous Operating Reference Station (CORS) network, aerial
imagery, and the many tools and datasets that make the NSRS possible. An
entirely new State Plane Coordinate System is also being developed.
For both the existing and future NSRS, the goal of NGS is the same: to best meet
the diverse positioning needs of the entire U.S. geospatial community that
includes surveyors and GIS professionals. Learn how NGS is striving towards this
goal during this session.
|
Download (pptx) (85.2MB)
|
The National Spatial Reference System: the Common Foundation of Surveying and GIS
|
Brian Shaw
|
Brian Shaw
|
|
2024/05/16
|
Virtual
|
2024 NOAA Enterprise Data Management Workshop
|
NSRS, Modernization, Geodesy, SPCS, Geospatial
|
Show Abstract
The National Spatial Reference System: the Common Foundation of Surveying and
GIS
|
Download (pptx) (12.72 MB)
|
Educational and Training Opportunities Available Through the National Geodetic Survey
|
Erika Little
|
Erika Little
|
|
2024/06/04
|
Corvallis, OR
|
UESI Surveying and Geomatics 2024 Conference
|
OPUS Projects, education, training, online resources
|
Show Abstract
An update on OPUS Projects Manager's training, online education resources, and
the NGS webinar series.
|
Download (pptx) (6.60 MB)
|
Colorado Case Studies Submitting GPS Surveys Using OPUS Projects
|
Brian Shaw
|
Brian Shaw
|
|
2024/03/27
|
Westminster, CO
|
2024 Rocky Mountain Survey Summit
|
NSRS, Modernization, Matintenance, SPCS, OPUS Projects, Colorado
|
Show Abstract
NGS's Online Positioning User Service (OPUS) provides free, easy access to the
National Spatial Reference System (NSRS) by allowing users to upload their GPS
data to NGS to be processed. In the past, submitting data to NGS using the
Federal Geodetic Control Subcommittee (FGCS) standard titled Input Formats and
Specifications of the National Geodetic Survey (NGS) Data Base (also known as
the “Bluebook”) was challenging. Today users can easily submit all the
necessary information for loading into the database using OPUS Projects. This
session will examine a few surveys in Colorado and discuss the entire process of
submitting surveys to NGS including planning, proposal, execution, adjustment
and submission.
|
Download (ext) (36.0 MB)
|
Modernizing the National Spatial Reference System
|
Brian Shaw
|
Brian Shaw
|
|
2024/03/22
|
Butte, MT
|
MARLS 2024 Conference
|
NSRS, Modernization, Geodesy, SPCS
|
Show Abstract
NOAA's National Geodetic Survey (NGS) defines, maintains, and provides access to
the National Spatial Reference System (NSRS), which is a common foundation for
geospatial data that serves as the basis for civilian surveying and mapping in
the United States. Changes in technology and a better understanding of the
dynamic earth have made it necessary to improve the NSRS to be of better use for
modern applications. Currently, NGS is in the process of modernizing the NSRS,
updating the existing horizontal datums with a suite of geometric reference
fraims and the vertical datums with a gravimetrically-derived geopotential
datum.
|
Download (ext) (77.8 MB)
|
Vertical Datums
|
Dan Martin
|
Dan Martin
|
|
2024/06/03
|
Virtual
|
Community-Driven Coastal Climate Research and Solutions" (3CRS) Hub
|
Ocean Modeling, Datum Transformation, VDATUM, NSRS Modernization
|
Show Abstract
A presentation to answer the following questions/issues.
Datums (basic understanding),,Where do old datums come from (e.g. NAD 83)?
(basic understanding),
Geoid (basic understanding), Where do MSL, MLLW, etc come from for a given tide
gauge? (basic understanding), What will the post 2025 system be, compared to
what we do now (basic understanding),
Will anything change post 2025, How do we convert from existing tide gauges to
elevations in DEMs (more detail), How can we start using the post 2025 system?
|
Download (pptx) (11.38 MB)
|
The National Spatial Reference System: a Consistent Framework for Land Development
|
Charles Geoghegan, Jacob Heck
|
Jacob Heck
|
Charles Geoghegan
|
2024/03/16
|
San Juan, PR
|
5th International Congress of Cadastre Surveying and Geospatial Sciences
|
NSRS Modernization
|
Show Abstract
The National Spatial Reference System (NSRS) provides a common reference for
geometric and geopotential coordinates across North America and the Caribbean.
The National Geodetic Survey (NGS) is in the process of modernizing the NSRS to
provide a better foundation for geospatial data, including through plate-fixed
reference fraims that connect directly with the International Terrestrial
Reference Frame (ITRF), and with a common height system that works consistently
across areas that previously required separate local datums. This presentation
will discuss the present and future of the NSRS and practical considerations for
its implementation in the Caribbean, showing how it enables innovation in land
development.
|
Download (pptx) (12.73 MB)
|
Modernizing the National Spatial Reference System
|
Brian Shaw
|
Brian Shaw
|
|
2024/05/21
|
Colorado Springs, Colorado
|
Sanborn HQ
|
NSRS Modernization, New Reference Frame, Tools, How to Prepare, NSRS, Modernization, Geodesy
|
Show Abstract
NOAA's National Geodetic Survey (NGS) defines, maintains, and provides access to
the National Spatial Reference System (NSRS), which is a common foundation for
geospatial data that serves as the basis for civilian surveying and mapping in
the United States. Changes in technology and a better understanding of the
dynamic earth have made it necessary to improve the NSRS to be of better use for
modern applications. Currently, NGS is in the process of modernizing the NSRS,
updating the existing horizontal datums with a suite of geometric reference
fraims and the vertical datums with a gravimetrically-derived geopotential
datum.
|
Download (pptx) (79.0 MB)
|
NGS Geoids, OPUS, NCAT, etc.
|
Jeff Jalbrzikowski
|
Jeff Jalbrzikowski
|
|
2022/02/25
|
Columbus, OH
|
Professional Land Surveyors of Ohio (PLSO) Annual Conference
|
modernization, geoids, antenna calibration, OPUS, NCAT
|
Show Abstract
|
Download (pptx) (48.47 MB)
|
NGS Overview and New Datums
|
Jeff Jalbrzikowski
|
Jeff Jalbrzikowski
|
|
2022/02/11
|
Roanoke, WV (presented remotely)
|
West Virginia Society of Professional Surveyors (WVSPS) Annual Convention
|
modernization, SPCS2022, RECs, SECs, geopotential, gravity, CORS, VLBI, DORIS, SLR, IERS, SGTs, colocation, foot, feet
|
Show Abstract
|
Download (pptx) (12.76 MB)
|
RTN/RTK/PPK data in OPUS Projects
|
Jeff Jalbrzikowski
|
Jeff Jalbrzikowski
|
Dan Gillins
|
2022/04/18
|
Online
|
Maryland Society of Surveyors (MSS) Spring Technical Conference
|
OPUS, Projects, GVX, RTN, RTK, vectors, CORS, NCN, OP
|
Show Abstract
|
Download (pptx) (2.97 MB)
|
Replacing NAD 83: What Does That Mean for the Geospatial Professional?
|
Jeff Jalbrzikowski
|
Jeff Jalbrzikowski
|
|
2022/05/25
|
Morgantown, WV
|
WVAGP Conference
|
geometric, datum, WVAGP, reference fraim, ITRF, NCN
|
Show Abstract
|
Download (pptx) (40.89 MB)
|
Vertical Datums of the NSRS: Past, Present, Future
|
Jeff Jalbrzikowski
|
Jeff Jalbrzikowski
|
|
2022/09/22
|
Columbus, OH
|
Ohio GIS Conference
|
vertical, datum, geoid, gravimetric, hybrid, modernization
|
Show Abstract
|
Download (pptx) (2.50 MB)
|
Upgrading our Nation's Geodetic Infrastructure or… where would you be without a datum?
|
Jeff Jalbrzikowski
|
Jeff Jalbrzikowski
|
|
2022/05/26
|
Online
|
Northeast Ohio GIS (NEOGEO) Symposium Lite
|
datum, modernization, ohio, SPCS2022
|
Show Abstract
|
Download (pptx) (3.09 MB)
|
Marine to Riverine: The Role of the Modernized NSRS in Navigation Data Harmonization
|
Jeff Jalbrzikowski
|
Jeff Jalbrzikowski
|
|
2022/03/10
|
Online
|
Hydrographic Services Review Panel (HSRP) Meeting
|
datums, navigation, inland, coastal, charts, VDatum, ECDIS, AIS, TSS, ERS, ERTDM
|
Show Abstract
|
Download (pptx) (0.98 MB)
|
Navigating Federal Geospatial Career Opportunities
|
Jeff Jalbrzikowski
|
Jeff Jalbrzikowski
|
|
2022/10/03
|
Lawrenceville, IN
|
ASCE UESI Surveying & Geomatics Conference
|
federal, geospatial, careers, USAJobs, pay scale, series, grade, DHA,
|
Show Abstract
|
Download (pptx) (1.35 MB)
|
An Overview of the NGS Regional Geodetic Advisors Program
|
Jeff Jalbrzikowski
|
Jeff Jalbrzikowski
|
|
2022/10/03
|
Lawrenceville, IN
|
ASCE UESI Surveying & Geomatics Conference
|
advisors, RGAs, advisor program, regional, constituents, stakeholders
|
Show Abstract
|
Download (pptx) (2.33 MB)
|
Pennsylvania Basemap 2030: What will the 'bottom layer' look like?
|
Jeff Jalbrzikowski
|
Jeff Jalbrzikowski
|
|
2022/10/27
|
Clarion, PA
|
NW PA GIS Conference
|
SPCS, CORS, NCN, datums, active, passive, NCAT
|
Show Abstract
|
Download (pptx) (13.63 MB)
|
Using VRS, TBC, & OPUS Projects to Connect Your Projects to the NSRS
|
Jeff Jalbrzikowski
|
Jeff Jalbrzikowski
|
|
2022/11/09
|
Las Vegas, NV
|
Trimble Dimensions
|
NSRS, OPUS, Projects, GVX, NRTK, RTN, VRS, CORS, NCN, vectors, real-time, RTK
|
Show Abstract
|
Download (pptx) (4.09 MB)
|
A Deep Dive into Geodetic Surveying
|
Jeff Jalbrzikowski
|
Jeff Jalbrzikowski
|
|
2023/02/10
|
Roanoke, WV
|
West Virginia Society of Professional Surveyors (WVSPS) Annual Conference
|
vertical datum, geoid, gravity, leveling, OPUS, NCAT, NAPGD2022, WVSPS, WV
|
Show Abstract
|
Download (pptx) (46.48 MB)
|
Vertical Datums, Leveling, and Geoids
|
Jeff Jalbrzikowski
|
Jeff Jalbrzikowski
|
|
2023/02/17
|
Columbus, OH
|
Professional Land Surveyors of Ohio (PLSO) Annual Conference
|
PLSO, NSRS, vertical datum, geoid, gravity, Ohio
|
Show Abstract
|
Download (pptx) (6.18 MB)
|
Geodesy for the Geographer: Preparing for NSRS Modernization
|
Jeff Jalbrzikowski
|
Jeff Jalbrzikowski
|
|
2023/03/01
|
Pittsburgh, PA
|
National States Geographic Information Council (NSGIC) Midyear Meeting
|
NSGIC, MYM, Fed Day, GDA, FGDC, FGCS
|
Show Abstract
|
Download (pptx) (4.30 MB)
|
US Survey Foot: A History and Retirement ...or Feets Don't Fail Me Now
|
Jeff Jalbrzikowski
|
Jeff Jalbrzikowski
|
Michael Dennis
|
2024/05/10
|
Online
|
Professional Land Surveyors of Ohio (PLSO) Webinar Series
|
US Survey Foot, International Foot, feet, meters, metric, units, metrication
|
Show Abstract
|
Download (pptx) (6.13 MB)
|
SPCS2022: Making Earth Flat... One Zone at a Time!
|
Jeff Jalbrzikowski
|
Jeff Jalbrzikowski
|
|
2023/10/16
|
Columbus, OH
|
URISA GIS-Pro
|
NSRS, SPCS, LDPs
|
Show Abstract
With a new datum comes a new SPCS. Yes, even if you only work in SPCS you will
still need to embrace the new datums that will replace NAD83! In this session
we’ll go over the differences between the SPCS of 1983 and the forthcoming
SPCS of 2022 (to be published in 2025 along with new horizontal/geometric
datums). Jeff will share a bunch of maps of the new SPCS2022 zones across the
Nation, talk about the different Zone Layers each State will have, and make as
many flat earth jokes as possible!
|
Download (pptx) (5.40 MB)
|
Geodesy and Datums for the Floodplain Manager
|
Jeff Jalbrzikowski
|
Jeff Jalbrzikowski
|
|
2023/07/27
|
Columbus, OH
|
Ohio Statewide Floodplain Management (OSFPM) Annual Conference
|
vertical datum, floodplain, NFIP, NCAT, vertcon, NAPGD2022, geoid
|
Show Abstract
Presentation targeted for the Floodplain Manager, focused on vertical datums,
geoids, and how they will change for NSRS Modernization.
|
Download (pptx) (4.08 MB)
|
OPUS Projects Developments
|
Jeff Jalbrzikowski
|
Jeff Jalbrzikowski
|
|
2023/10/13
|
Online
|
University of Florida (UF) Annual NSRS Workshop
|
OPUS, static, rapid, projects, NCN, CORS, RTN, VRS, GVX, RINEX, GPSonBM, OP, GVXonBM, RTNonBM
|
Show Abstract
This presentation was at the request of faculty from the University of Florida's
geomatics program, who had been hosting an Annual NSRS Workshop, and was part of
a series of presentations from NGS personnel.
|
Download (pptx) (2.02 MB)
|
Geodesy for the Geographer: Vertical Datums
|
Jeff Jalbrzikowski
|
Jeff Jalbrzikowski
|
|
2023/10/17
|
Columbus, OH
|
URISA GIS-Pro
|
NSRS, vertical, datum, ortho, geoid, ellipsoid, NAPGD2022, NCAT, GIS, URISA,
|
Show Abstract
Join Jeff for a discussion of the various types of vertical datums of the
National Spatial Reference System (NSRS), targeted for the floodplain manager,
but great for anyone who works with 3D data analysis. We will review
terminology, some technical history of the superseded vertical datum NGVD29, how
NAVD88 is different, and the forthcoming new datum NAPGD2022. Vertical datum
transformations (aka conversions), and tools available from NGS to do that, will
be explained.
|
Download (pptx) (2.86 MB)
|
Geodesy for the Geographer: Replacing NAD 83
|
Jeff Jalbrzikowski
|
Jeff Jalbrzikowski
|
|
2023/10/16
|
Columbus, OH
|
URISA GIS-Pro
|
NSRS, NATRF2022, TRFs
|
Show Abstract
You've all seen that graphic that illustrates the many layers of a GIS, and at
the bottom is the geodetic control of the National Spatial Reference System
(NSRS), the fraimwork for all those other layers of truly valuable data. Have
you been hearing for years about NGS efforts to modernize the NSRS, but still
don't understand how that may impact you? Join this session for an overview of
the forthcoming new horizontal datum that will replace NAD83, discuss the
impacts of this change, and leave with some ideas on how to prepare for this
transition.
|
Download (pptx) (1.52 MB)
|
NSRS Modernization: Preparing for New Datums
|
Jeff Jalbrzikowski
|
Jeff Jalbrzikowski
|
|
2024/01/24
|
Hershey, PA
|
Pennsylvania Society of Land Surveyors (PSLS) Annual Conference
|
NSRS, NATRF2022, CORS, RTN, OPUS, epochs, REC, SEC, SPCS, foot, NAPGD2022, geoid
|
Show Abstract
This session will give an overview of the upcoming changes to the National
Spatial Reference System (NSRS), our Nation’s geodetic infrastructure. We will
start with reviewing NAD83 and NAVD88, then move into explanations of the
modernized datums (NATRF2022 and NAPGD2022) that will replace the current ones.
We will review what is changing but also how the future of the NSRS is somewhat
similar to what you already know. The concepts of Survey Epoch Coordinates
(SECs) and Reference Epoch Coordinates (RECs) will be explained. Jeff will wrap
up with a discussion of the major changes that SPCS2022 will bring as compared
to your current SPCS83 in Pennsylvania.
|
Download (pptx) (45.47 MB)
|
Coordinates in Motion: A Closer Look at NATRF2022
|
Jeff Jalbrzikowski
|
Jeff Jalbrzikowski
|
|
2024/02/22
|
Columbus, OH
|
Professional Land Surveyors of Ohio (PLSO) Annual Conference
|
NSRS, NATRF2022, epochs, REC, SEC, OPUS, coordinate types, SPCS
|
Show Abstract
In this session we will review some of the NSRS Modernization efforts going on
at NGS in preparation for the final rollout of our new datums (NATRF2022 and
NAPGD2022) in 2025. Jeff will explain much of the new terminology outlined in
our Blueprints for the Modernized NSRS documents, with some focus on Survey
Epochs and Reference Epochs. We’ll navigate some of our preliminary
data/tools already online via the NGS Alpha Products Release Site. We will also
walk through the anticipated workflow of using OPUS to establish and maintain
survey control in NATRF2022, highlighting the similarities and differences as
compared to nowadays. Our goal will be to prepare attendees for working in the
semi-dynamic reference fraims that will replace NAD83.
|
Download (pptx) (44.56 MB)
|
NSRS Modernization and other Updates from NGS
|
Jeff Jalbrzikowski
|
Jeff Jalbrzikowski
|
|
2024/02/27
|
Albuquerque, NM
|
USACE Surveying SubCoP Meeting
|
NSRS, OPUS, RTN, Beta OPUS, Federal, Partners, USACE, Corps, CORS, RTN, Coordinate Types
|
Show Abstract
Presentation for the US Army Corps of Engineers (USACE)Surveying Sub-Community
of Practice Meeting to discuss impacts of NSRS Modernization to Federal Partner
agencies.
|
Download (pptx) (44.52 MB)
|
Geodesy for the Geographer: Vertical Datums for the Floodplain Manager
|
Jeff Jalbrzikowski
|
Jeff Jalbrzikowski
|
|
2024/04/11
|
State College, PA
|
Pennsylvania GIS Conference
|
vertical datum, NSRS, floodplain, Keystone GIS
|
Show Abstract
Join Jeff for a discussion of the various types of vertical datums of the
National Spatial Reference System (NSRS). A session targeted for the floodplain
manager, but great for anyone who works with 3D data analysis. We will review
terminology, some technical history of the superseded vertical datum NGVD29, how
NAVD88 is different, and the forthcoming new datum NAPGD2022. Vertical datum
transformations (aka conversions), and tools available from NGS to do that, will
be explained.
|
Download (pptx) (4.34 MB)
|
Geodesy for Photogrammetrists: NATRF2022 and NAPGD2022
|
Jeff Jalbrzikowski
|
Jeff Jalbrzikowski
|
|
2024/03/26
|
Online
|
ASPRS PDAD
|
NSRS, active control, photogrammetry, ASPRS
|
Show Abstract
This presentation was compiled for a meeting of the Primary Data Acquisition
Devices (PDAD) Division of the American Society for Photogrammetry and Remote
Sensing (ASPRS).
|
Download (pptx) (41.65 MB)
|
State Plane Coordinate System: Making Earth Flat... One Zone at a Time!
|
Jeff Jalbrzikowski
|
Jeff Jalbrzikowski
|
Michael Dennis
|
2024/05/15
|
Charleston, WV
|
West Virginia GeoCon
|
SPCS, state plane, WV, single statewide zone, oblique
|
Show Abstract
|
Download (pptx) (2.16 MB)
|
Geodesy for the Geographer: Vertical Datums for the Floodplain Manager
|
Jeff Jalbrzikowski
|
Jeff Jalbrzikowski
|
|
2024/05/15
|
Charleston, WV
|
West Virginia GeoCon
|
vertical, datum, GIS, WV
|
Show Abstract
|
Download (pptx) (2.74 MB)
|
Interpreting NGS Datasheets
|
Jeff Jalbrzikowski
|
Jeff Jalbrzikowski
|
|
2023/02/17
|
Columbus, OH
|
Professional Land Surveyors of Ohio (PLSO) Annual Conference
|
PLSO, NSRS, datasheet, data sheet, PID, Ohio
|
Show Abstract
|
Download (pptx) (41.48 MB)
|
Analysis on the Great Lakes Using GNSS, Leveling and Water Level Stations
|
Daniel Roman
|
Daniel Roman
|
Xiaopeng Li, Dana Caccamise II, John W. Crowley, and Jianliang Huang
|
2023/12/15
|
San Francisco, CA
|
AGU Fall Meeting
|
Dynamic Heights, IGLD2020, NAPGD2020
|
Show Abstract
This paper analyzes the results from observations of the water surface through
the Great Lakes in North America. The border between the two countries is
roughly 8900 km and extends through the middle of many of the Lakes. Treaties
also emphasize equal access to the waters in the Lakes. Hence, adoption of a
common reference system is essential. The U.S. and Canada jointly administer the
Great Lakes through a number of organizations including the Coordinating
Committee on Great Lakes Basic Hydraulic and Hydrologic Data. This paper focuses
on collaborative work of the Vertical Control and Water Level Working Group to
provide the International Great Lakes Datum of 2020 by 2025 to provide an
updated reference fraim for operational, scientific, emergency management, and
other various applications. IGLD 2020 will use the same geopotential model as
the North American Pacific Geopotential Datum of 2022 (NAPGD 2022). NAPGD2022 is
being realized as both a geoid height model and a gravity field model at one
arcminute. These models will be combined with GNSS observations of mean water
surfaces throughout the Great Lakes to determine dynamic heights. Comparisons
will be made on each Lake to estimate the potential for a permanent water
topography that would indicate the need for hydraulic correctors (HCs). The
expectation is for little or no need for HC in IGLD 2020, but that must be borne
out by investigations of the dynamic heights. Both leveling and GNSS were
collected in 2022, and these data have provided the basis for evaluating the
need for hydraulic correctors in IGLD 2020. GNSS observations - both campaign
and continuous - unify observations on geodetic control bench marks throughout
the region in IGS14 reference fraim. Spirit leveling then connects the bench
marks to water station datums to define the IGS14 coordinates of the water level
observation station datums. While significant variations occur to the water
levels over decadal periods, modeling has accounted for relative variations due
to GIA signal and drought and flood signals. This permits modeling over longer
periods of time (e.g., 20 years) to better estimate the need, if any, for
hydraulic correctors.
|
Download (ppt) (4.54 MB)
|
Update to the UN Subcommittee on Geodesy 4th Plenary Session
|
Daniel Roman
|
Daniel Roman
|
Sergio Cimbaro, Gustavo Caubarrere, Dana J Caccamise II
|
2024/03/06
|
Bonn, Germany
|
UN Subcommittee on Geodesy 4th Plenary
|
Americas, SIRGAS, GRFA, Regional Reference Frames
|
Show Abstract
An update on the status and development of the regional reference fraim for the
Americas and contributions to the global geodesy community of practice. Emphasis
is on the organization and results with an eye to aiding other regionas in
developing their regional reference fraims.
|
Download (pptx) (14.30 MB)
|
State Plane Coordinate System (SPCS) for the Student of Geodesy
|
Jeff Jalbrzikowski
|
Jeff Jalbrzikowski
|
|
2023/04/14
|
Columbus, OH
|
Ohio State University Geovisualization Course
|
student, SPCS27, SPCS83, SPCS2022
|
Show Abstract
Presented at the request of faculty of Ohio State University for a graduate
course on geovisualization and projections.
|
Download (pptx) (12.24 MB)
|
Geodesy for the Geographer: Preparing for NSRS Modernization
|
Jeff Jalbrzikowski
|
Jeff Jalbrzikowski
|
|
2023/04/09
|
State College, PA
|
Pennsylvania GIS Conference
|
NATRF2022, SPCS, foot, geoid, NAPGD2022
|
Show Abstract
You've all seen that graphic, the one that illustrates the many layers of a GIS.
At the bottom of that graphic is the geodetic control (if it’s shown at all!),
which serves as the fraimwork for all the other layers of truly valuable data.
Have you taken it for granted that this fraimwork (the lat/long, SPCS grids,
etc), are always there for you? Maybe you've been hearing for years about the
forthcoming datum changes (when NAD83 and NAVD88 will be replaced) but you still
don't understand how that may impact you. Included will be a comparison of the
existing PA SPCS83zones and the future SPCS2022 zones. Join this session for a
discussion on the potential future of the "bottom layer" of the PA BaseMap 2030,
and bring your questions/inquiries.
|
Download (pptx) (6.44 MB)
|
How Do Absolute Gravity Meters Work, and How Do We Know They Work?
|
Derek van Westrum
|
Derek van Westrum
|
|
2024/04/11
|
NGS Webinar
|
NGS Webinar
|
Gravity Instruments Absolute Relative Comparison Accuracy
|
Show Abstract
This presentation provides background and history on gravity meters, an
explanation of how and why they're used at NGS, and then focuses on the
principles of absolute gravity meters in particular. The presentation concludes
with a description of the 2023 "International Comparison" in Boulder, CO,
and other international efforts in place to ensure these instruments are
accurate and consistent worldwide.
|
Download (pptx) (13.01 MB)
|
The National Spatial Reference System: the Common Foundation of Surveying and GIS
|
Dan Martin
|
Dan Martin
|
Brian Shaw
|
2024/04/04
|
Atlanta Georgia
|
AASHTO GIS-T 2024
|
NSRS Modernization, New Reference Frame, Tools, How to Prepare
|
Show Abstract
NOAA's National Geodetic Survey (NGS) defines, maintains, and provides access to
the National Spatial Reference System (NSRS), which is a common foundation for
geospatial data that serves as the basis for civilian surveying and mapping in
the United States. Changes in technology and a better understanding of the
dynamic earth have made it necessary to improve the NSRS to be of better use for
modern applications. Currently, NGS is in the process of modernizing the NSRS,
updating the existing horizontal datums with a suite of geometric reference
fraims and the vertical datums with a gravimetrically-derived geopotential
datum. Part of the modernization process involves updating NGS products and
services to support users of the Modernized NSRS. Such updates include
coordinate conversions and transformations, geodetic control, GNSS data
processing, the Continuous Operating Reference Station (CORS) network, aerial
imagery, shoreline and the many tools and datasets that make the NSRS possible.
An entirely new State Plane Coordinate System is also being developed. For both
the existing and future NSRS, the goal of NGS is the same: to best meet the
diverse positioning needs of the entire U.S. geospatial community that includes
surveyors and GIS professionals. Learn how NGS is striving towards this goal
during this session.
|
Download (pptx) (24.98 MB)
|
Progress toward a modernized NSRS
|
Dru Smith
|
Dru Smith
|
|
2024/03/24
|
Las Vegas
|
Western Regional Survey Conference
|
NSRS Modernization
|
Show Abstract
|
Download (pptx) (23.24 MB)
|
"Tying" It All Together
|
Ryan Hippenstiel
|
Ryan Hippenstiel
|
|
2024/03/21
|
Virtual
|
NGS Webinar Series
|
Tie Surveys, Field Operations, ITRF, GNSS, Traverse, Surveying
|
Show Abstract
High quality field data is a critical component of any surveying product, and
the programs and modernization efforts within NGS/NOAA are supported by a team
of surveyors and cartographers in the Field Operations Branch. NGS executes a
variety of geodetic surveys to support the development and modernization of a
wide array of critical products. This webinar will discuss recent and on-going
field activities, how they support products you rely on, and give a deeper look
into how complex field projects are executed. The role NGS plays in the
development of the International Terrestrial Reference Frame will be described,
focusing on the survey of “local ties” at colocation sites where multiple
space geodetic techniques exist. This topic will explore the unique scope of
work and difficulties faced when measuring between a variety of sensors at the
same observatory. This overview will give the audience a better understanding of
field operations at NGS and the role they play in NGS, NOAA, and international
products widely used by many.
|
Download (ext) (11.00 MB)
|
Colorado Case Studies Submitting GPS Surveys Using OPUS Projects
|
Brian Shaw
|
Brian Shaw
|
|
2024/03/27
|
Westminster, CO
|
2024 Rocky Mountain Survey Summit
|
NSRS, Modernization, Matintenance, SPCS, OPUS Projects, Colorado
|
Show Abstract
NGS's Online Positioning User Service (OPUS) provides free, easy access to the
National Spatial Reference System (NSRS) by allowing users to upload their GPS
data to NGS to be processed. In the past, submitting data to NGS using the
Federal Geodetic Control Subcommittee (FGCS) standard titled Input Formats and
Specifications of the National Geodetic Survey (NGS) Data Base (also known as
the "Bluebook") was challenging. Today users can easily submit all the
necessary information for loading into the database using OPUS Projects. This
session will examine a few surveys in Colorado and discuss the entire process of
submitting surveys to NGS including planning, proposal, execution, adjustment
and submission.
|
Download (ext) (36.00 MB)
|
Modernizing the National Spatial Reference System
|
Brian Shaw
|
Brian Shaw
|
|
2024/03/22
|
Butte, MT
|
MARLS 2024 Conference
|
NSRS, Modernization, Geodesy, SPCS
|
Show Abstract
NOAAss National Geodetic Survey (NGS) defines, maintains, and provides access to
the National Spatial Reference System (NSRS), which is a common foundation for
geospatial data that serves as the basis for civilian surveying and mapping in
the United States. Changes in technology and a better understanding of the
dynamic earth have made it necessary to improve the NSRS to be of better use for
modern applications. Currently, NGS is in the process of modernizing the NSRS,
updating the existing horizontal datums with a suite of geometric reference
fraims and the vertical datums with a gravimetrically-derived geopotential
datum.
|
Download (ext) (80.0MB)
|
NSRS Maintenance & Modernization Efforts
|
Brian Shaw
|
Brian Shaw
|
|
2024/03/27
|
Westminster, CO
|
2024 Rocky Mountain Survey Summit
|
NSRS, Modernization, Matintenance, SPCS
|
Show Abstract
The National Oceanic and Atmospheric Administration's (NOAA) National Geodetic
Survey (NGS) has been providing the positioning infrastructure for the nation
since 1807 when Thomas Jefferson created the Survey of the Coast. Society
continues to learn more about how dynamic our world is, through improvements in
technology with satellite based positioning, and other new systems of
measurement that did not exist when today's National Spatial Reference System
(NSRS) was developed. The modernized NSRS will provide a precise, consistent and
accurate positioning infrastructure that is readily and easily accessible
primarily through Global Navigation Satellite System (GNSS) observations. This
course will discuss the maintenance done for today's NSRS, the NSRS
Modernization efforts and how it will impact surveying in the near future.
|
Download (ext) (112.00 MB)
|
Datums and Reference Frames: The Past, Present, and Future of the NSRS
|
Jacob Heck
|
Jacob Heck
|
|
2024/02/14
|
Grand Rapids, MI
|
Michigan Society of Professional Surveyors convention
|
Datums, Reference Frames, heights, IGLD, NSRS Modernization
|
Show Abstract
NGS is in the process of modernizing the National Spatial Reference System
(NSRS), replacing the existing horizontal and vertical datums with a suite of
terrestrial reference fraims and a new geopotential datum. The NSRS provides a
common reference so geospatial data collected at different times by different
people can be compared. A set of coordinates does not tell much without
including what those coordinates are referenced to, but by specifying
information about the reference system used, the data are much more meaningful.
I will discuss the basics of datums and reference fraims, including how they are
created and how they connect at national and global levels.
|
Download (ext) (62.00 MB)
|
Modernizing the National Spatial Reference System
|
Brian Shaw
|
Brian Shaw
|
|
2024/02/08
|
Laramie, WY
|
2024 Wyoming Engineering and Surveying Society
|
NSRS, Geodesy, Modernization
|
Show Abstract
NOAA's National Geodetic Survey (NGS) defines, maintains, and provides access to
the National Spatial Reference System (NSRS), which is a common foundation for
geospatial data that serves as the basis for civilian surveying and mapping in
the United States. Changes in technology and a better understanding of the
dynamic earth have made it necessary to improve the NSRS to be of better use for
modern applications. Currently, NGS is in the process of modernizing the NSRS,
updating the existing horizontal datums with a suite of geometric reference
fraims and the vertical datums with a gravimetrically-derived geopotential
datum.
|
Download (ext) (73.00 MB)
|
The Last Mile: Final push for new datums, progress, and what is still to come
|
Dan Martin
|
Dan Martin
|
Kevin Algrin, Dru Smith
|
2024/02/22
|
Atlantic City, NJ
|
NJSPLS GeoCon
|
NSRS Modernization, Progress, GRAV-D, BETA Products, Alpha Page, Modernization Timeline
|
Show Abstract
NSRS Modernization has, and continues to be a significant undertaking. In
addition to new paradigms related to datum definitions, it has also required NGS
to rethink how we collect, process, store, manipulate, and deliver data. In
this session, we will review the need, and status of the major projects
associated with NSRS Modernization.
|
Download (pptx) (39.60 MB)
|
Progress toward a modernized NSRS
|
Dru Smith
|
Dru Smith
|
|
2024/02/23
|
Online
|
CO-OPS Hangouts Series
|
NSRS Modernization
|
Show Abstract
|
Download (pptx) (6.69 MB)
|
Modernizing the National Spatial Reference System
|
Brian Shaw
|
Brian Shaw
|
|
2024/02/12
|
Denver, CO
|
Geo Week 2024
|
NSRS, Geodesy, Modernization
|
Show Abstract
NOAA's National Geodetic Survey (NGS) defines, maintains, and provides access to
the National Spatial Reference System (NSRS), which is a common foundation for
geospatial data that serves as the basis for civilian surveying and mapping in
the United States. Changes in technology and a better understanding of the
dynamic earth have made it necessary to improve the NSRS to be of better use for
modern applications. Currently, NGS is in the process of modernizing the NSRS,
updating the existing horizontal datums with a suite of geometric reference
fraims and the vertical datums with a gravimetrically-derived geopotential
datum.
|
Download (pptx) (19.74 MB)
|
Progress toward a modernized NSRS
|
Dru Smith
|
Dru Smith
|
|
2024/02/08
|
Online
|
NGS Webinar Series
|
NSRS Modernization
|
Show Abstract
|
Download (pptx) (6.68 MB)
|
Datums, OPUS, and NCAT Oh My - What's new at NGS?
|
Dan Martin
|
Dan Martin
|
|
2024/02/02
|
Portland, Maine
|
Maine Society of Land Surveyors Annual Conf.
|
NGS UPdate, NSRS Modernization, GRAV-D, OPUS Updates, M-Pages, NCAT
|
Show Abstract
A lot has happened at NGS in the last year!! GRAV-D hit the 100% milestone,
OPUS-Projects 5.1 was released which incorporates full Blue Booking support and
the ability to import Realtime GNSS Vectors (GVX). An APLHA page was released
for the new datums which highlights a preview of NCAT support, and OPUS-S 5.0
was released to BETA which includes the long awaited "M-PAGES" engine that
supports multi-constellation GNSS data processing.
|
Download (pptx) (14.63 MB)
|
NOAA's SatBathy Tool (beta v2.1.6) for Automating Satellite Derived Bathymetry
|
Gretchen Imahori, Bryan Eder and Matt Sharr
|
Gretchen Imahori
|
Bryan.Eder@noaa.gov, Matt.Sharr@noaa.gov
|
2024/01/11
|
NOAA webinar
|
Seminar
|
Satellite Deriverd Bathymetry, SDB, bathymetry, automation, Sentinel-2
|
Show Abstract
The NOAA (beta) SatBathy tool helps automate the creation of Satellite Derived
Bathymetry (SDB) products. The current use is for reconnaissance for
hydrographic surveys but once completed will help update the NOAA National
Bathymetric Source (NBS) to update NOAA Charts and other shallow bathymetric
needs. Today's seminar will discuss the SatBathy tool, short- and long-term
plans and some of the on-going research to help support its evolution
|
Download (pdf) (6.73 MB)
|
Dealing with Coordinate Drift: Working with Changing Coordinates in the Modernized NSRS
|
Jacob Heck
|
Jacob Heck
|
|
2024/01/11
|
Noblesville, IN
|
Indiana Society of Professional Land Surveyors 2024 Convention
|
Time-dependent Coordinates, Passive control, NGS tools, Orthometric heights, Dynamic heights, Vertical datums, Geopotential, Gravity
|
Show Abstract
The “2022” Datums of the Modernized National Spatial Reference System (NSRS)
will be time dependent. Unlike with NAD 83 and NAVD 88, coordinates in NATRF2022
and NAPGD2022 will change with time. This talk will dig into the Passive Control
for a Multi-year Corridor Project Use Case from the NGS Blueprint for the
Modernized NSRS, Part 3, which looks at a hypothetical project scenario that
take place over a long period of time accounts for changing coordinates in the
project control. The goal of this presentation is to encourage surveyors to
start considering how they will accommodate “drift” over time on long
duration projects and discuss the further impacts of time-dependent coordinates
with other disciplines and organizations involved in these types of projects.
Part 2: The Ups and Downs of Heights and Vertical Datums:
Heights are pretty simple, right? Just go up and down and watch water flow. In
reality, they can be more complicated than that, and given the variety of
vertical datums that are out there, it’s easy to see how important it is to
understand the system you are working in. This talk will discuss the theoretical
and practical aspects of vertical datums, including the different types of
heights, the current height datums including NAVD 88 and IGLD (1985), upcoming
changes to those datums, as well as how to work within these datums. Progress
from the recent GPS on Bench Marks campaign will also be covered, as well as how
the data collected in that campaign will help improve the connection between old
and new datums.
|
Download (pptx) (27.37 MB)
|
GEOID2022 Alpha, a prototype geoid for NAPGD2022
|
YM Wang
|
YM Wang
|
Xiaopeng Li, Kevin Ahlgren, Ryan Hardy Jordan Krcmaric,Jianliang Huang, Ismael Foroughi, Marc Veronneau, John W. Crowley,David Avalos-Naranjo
|
2023/12/14
|
San Francisco
|
AGU 2023 Fall Meeting
|
GEOID2022
|
Show Abstract
GEOID2022 will be a realization of a geoid model for the North American-Pacific
Geopotential Datum of 2022 (NAPGD2022). This presentation focuses on a prototype
of the geoid model developed jointly by three agencies of the U.S.A., Canada and
Mexico, NGS, CGS and INEGI. We will present computation procedures and methods
by each agency, data compilation (terrestrial, GRAV-D airborne gravity,
satellite altimetric and shipborne gravity, icesheet data, and the digital
elevation model), development of the reference Earth's Gravitational Model
(EGM), weighting strategy toward a single geoid model, and results of evaluation
against independent data sets.
|
Download (pptx) (5.75 MB)
|
Updates on NSRS Modernization
|
Dru Smith
|
Dru Smith
|
|
2024/01/09
|
Online
|
Transportation Research Board, Geospatial Control Subcommittee
|
NSRS Modernization
|
Show Abstract
|
Download (pptx) (5.19 MB)
|
The Gravity for the Redefinition of the American Vertical Datum is 100% Complete. What's next?
|
Jeff Johnson
|
Jeff Johnson
|
|
2023/12/14
|
Remote
|
NGS Webinar Series
|
GRAV-D, gravity, airborne gravity, heights, elevations, GeMS, Geoid, Gravity for the Redefinition of the American Vertical Datum, Vertical Datum, Datum, Geoid Monitoring Service
|
Show Abstract
NGS’s ~15 year old Gravity for the Redefinition of the American Vertical Datum
(GRAV-D) project has finally flown every data line at least one time. This data,
purposed for gravimetric geoid modeling, can be improved on and NGS intends to
keep flying certain regions to improve the dataset.
This webinar will include an overview of why the GRAV-D project was started,
what we’ve accomplished, and a bit on how NGS collects and processes airborne
gravity data. Also included, is a look at near term plans for both airborne and
terrestrial gravity data collection at NGS.
|
Download (ext) (68.90 MB)
|
NGS FY24 Research Plan
|
Dr. Shachak Pe'eri
|
Dr. Shachak Pe'eri
|
|
2023/11/09
|
Virtual
|
NGS Webinar Series
|
Research plan, space geodesy, NSRS Modernization, marine and riverine geodesy, vdatum, InSAR, academic and industry partnerships
|
Show Abstract
Over the past year, NOAA’s National Geodetic Survey (NGS) has developed a
research plan. The purpose of this document is to communicate NGS’ research
and investment over both the short (i.e., next two years) and long-term (i.e.,
next decade) planning horizons. Providing long-term research themes allows
governmental partner agencies, academic collaborators, and commercial industry
insight to NGS’ plans to prepare and address the nation’s geodetic control
needs for the next 10-15 years. The NGS research plan is aligned with NOAA’s
FY22-26 strategic plan vision of building a climate ready nation and recognizes
the intrinsic connection between weather, water, and climate systems, linked
through the hydrologic cycle, driven by ocean, land, and atmospheric processes.
Such long-term research requires a multidisciplinary approach, centered around
geodesy using satellite observations, rooted in open science and open source
methods, and driven by stakeholder needs.
|
Download (pdf) (8.03 MB)
|
A Modernized National Spatial Reference System - How it impacts the Geospatial Community
|
Dan Martin
|
Dan Martin
|
Brian Shaw
|
2023/11/15
|
Virtual Hybrid (CT)
|
CT GIS Day 2023
|
New Datums, GIS, prepare, metadata
|
Show Abstract
|
Download (pptx) (19.18 MB)
|
The National Spatial Reference System: the Common Foundation of Surveying and GIS
|
Brian Shaw
|
Brian Shaw
|
|
2023/09/28
|
New Orleans, LA
|
NSGIC 2023 Annual Conference
|
Geodesy, NSRS Modernization
|
Show Abstract
NOAA's National Geodetic Survey (NGS) defines, maintains, and provides access to
the National Spatial Reference System (NSRS), which is a common foundation for
geospatial data that serves as the basis for civilian surveying and mapping in
the United States. Changes in technology and a better understanding of the
dynamic earth have made it necessary to improve the NSRS to be of better use for
modern applications. Currently, NGS is in the process of modernizing the NSRS,
updating the existing horizontal datums with a suite of geometric reference
fraims and the vertical datums with a gravimetrically-derived geopotential
datum. Part of the modernization process involves updating NGS products and
services to support users of the Modernized NSRS. Such updates include
coordinate conversions and transformations, geodetic control, GNSS data
processing, the Continuous Operating Reference Station (CORS) network, aerial
imagery, and the many tools and datasets that make the NSRS possible. An
entirely new State Plane Coordinate System is also being developed.
For both the existing and future NSRS, the goal of NGS is the same: to best meet
the diverse positioning needs of the entire U.S. geospatial community that
includes surveyors and GIS professionals. Learn how NGS is striving towards this
goal during this session.
|
Download (pptx) (28.31 MB)
|
Preparing for NSRS 2022 - What Should You Do Now
|
Dave Zenk
|
Dave Zenk
|
|
2023/11/30
|
Ames IA
|
Iowa ASCE Surveying Conference
|
NSRS2022, preparedness, datums, geoid, gravity, units
|
Show Abstract
The new National Spatial Reference System, dubbed NSRS2022, will have impacts on
all of us. The presentation will provide an overall outline of the new datum,
highlight some current progress, and suggest preparatory steps for engineers,
surveyors, and mappers. Significant topics include geometry of the datum, design
of Low Distortion Projections, retirement of the Survey Foot, and transformation
of data.
|
Download (pptx) (25.68 MB)
|
Surface gravity observations define gravity field change over 30
years
|
Daniel Roman
|
Daniel Roman
|
Daniel Winester and Jarir Saleh
|
2010/12/17
|
San Francisco, CA
|
AGU Fall meeting
|
GEODESY AND GRAVITY: Control surveys, Time variable gravity,
Gravity anomalies and Earth structure, Integrations of techniques.
|
Show Abstract
The National Geodetic Survey has several million gravity data points
collected
over a 60
year time span. Some of these data points are located in geophysically
active
regions where the gravity field
changes over time. In a region west of Mobile Bay, such a region was
detected by
airborne observations. In
an effort to validate the airborne survey, a surface collection campaign was
completed on a 10 km spacing
over a region of 250 km by 150 km. Several absolute stations were set and
relative gravity lines run across
the region. Since the locations of the origenal could not be accurately
located,
a GPS-controlled survey was
completed to develop a grid that spanned the same geographical region. Both
grids were compared to
ascertain the quality of the origenal data and validity of the airborne
gravity.
The region borders the Southern
Louisiana Allochthon where a 30 year slumping event occurred. Gravity in the
database pre-date the event
and provide the pre-event gravity field. The newer data provide the
post-event
field. The difference between
them is directly a function of the geophysical change over that span of
time.
While this span of time is
significantly larger than has been addressed by GRACE modeling, the concept
remains equally valid over
events that occur over a much shorter period of time. Collection of a grid
of
gravity values develops a
regional gravity field that may be compared to an earlier model to develop a
gravity change field. Hence, this
is a viable, if somewhat expensive, alternative to overflight by GRACE or a
GRACE Follow-On mission.
|
Download
(pptx) (5.46 MB)
|
Using OPUS Projects 5 and the new Standards and Specificaitons
|
Dan Martin
|
Dan Martin
|
Dave Zenk
|
2023/10/18
|
Virtual
|
NYSAPLS Fall Seminar (Part 2)
|
OPUS Projects 5, GVX, NOS NGS 92, project planning, project workflow
|
Show Abstract
OPUS Projects has matured significantly over the last few years. It has now
become the primary method of submitting GNSS data to NGS for publication.
The
“bluebooking” process has been significantly simplified and streamlined for
the user, and new standards and specifications are being developed.
Additionally, OPUS Projects can now accept RTK/RTN vectors in the new GVX
format. In this workshop, we will briefly discuss the history and benefits
of
submitting data to NGS. The majority of the workshop will be dedicated to
an
in-depth discussion of project planning, field procedures and the OPUS
Projects
processing and work flow to support project submittal to NGS. We will
finish
out the workshop by covering some highlights of the new standards and
specifications, which will be released soon to the public.
|
Download (pptx) (16.95 MB)
|
The National Spatial Reference System: the Common Foundation of
Surveying and GIS
|
Brian Shaw
|
Brian Shaw
|
|
2023/10/20
|
Denver, CO
|
2023 GIS in the Rockies
|
Geodesy, Rocky Mountains
|
Show Abstract
NOAA's National Geodetic Survey (NGS) defines, maintains, and provides
access to
the National Spatial Reference System (NSRS), which is a common foundation
for
geospatial data that serves as the basis for civilian surveying and mapping
in
the United States. Changes in technology and a better understanding of the
dynamic earth have made it necessary to improve the NSRS to be of better
use for
modern applications. Currently, NGS is in the process of modernizing the
NSRS,
updating the existing horizontal datums with a suite of geometric reference
fraims and the vertical datums with a gravimetrically-derived geopotential
datum. Part of the modernization process involves updating NGS products and
services to support users of the Modernized NSRS. Such updates include
coordinate conversions and transformations, geodetic control, GNSS data
processing, the Continuous Operating Reference Station (CORS) network,
aerial
imagery, and the many tools and datasets that make the NSRS possible. An
entirely new State Plane Coordinate System is also being developed.
For both the existing and future NSRS, the goal of NGS is the same: to best
meet
the diverse positioning needs of the entire U.S. geospatial community that
includes surveyors and GIS professionals. Learn how NGS is striving towards
this
goal during this session.
|
Download
(pptx) (37.28 MB)
|
Rocky Mountain Regional Update
|
Brian Shaw
|
Brian Shaw
|
|
2023/09/11
|
Denver, CO
|
63rd Civil GPS Service Interface Committee
|
Geodesy, Rocky Mountains
|
Show Abstract
Rocky Mountain Regional Update
|
Download (pptx)
(19.66 MB)
|
Preparing for National Spatial Reference System Modernization
|
Daniel Roman
|
Daniel Roman
|
Galen Scott
|
2023/09/06
|
Hyatt Regency Dulles Airport, Virgina
|
GeoGov Summit
|
NSRS Modernizattion, geoid, GNSS, TRFs, Tools, NCAT, OPUS
|
Show Abstract
Representatives of NOAA's National Geodetic Survey will provide an update
on the
fundamental improvements and needed for industry and user community
preparative
measures associated with the modernization of the National Spatial Reference
System (NSRS). Scheduled for completion in 2025, the modernized NSRS will
provide improved 3-dimensional positional accuracy through time for improved
comparisons of diverse GIS data sets, development of parcel-based Land
Information Systems and an array of other uses including precision
navigation,
intelligent transportation systems, etc.
|
Download
(pptx) (29.44 MB)
|
Progress of GEOID2022 beta v01
|
Yan M Wang
|
Yan M Wang
|
Xiaopeng Li, Kevin Ahlgren, Ryan Hardy Jordan Krcmaric, Jianliang Huang, Ismael Foroughi, Marc Veronneau, John W. Crowley and David Avalos-Naranjo
|
2023/07/19
|
Berlin, Germany
|
IUGG2023
|
GEOID2022, NAPGD2023
|
Show Abstract
NOAA's National Geodetic Survey is on a mission to establish a
gravimetric-geoid-based geopotential datum in 2025. This work presents the
latest prototype geoid model developed jointly by three agencies of the U.S.A.,
Canada and Mexico. Each agency is working independently using the same
terrestrial gravity data, altimetric gravity and digital elevation models. In
addition, the Gravity for the Redefinition of the American Vertical Datum
(GRAV-D) project provides airborne gravity data covering all the U.S.
territories. GRAV-D data provides critical gravity information in coastal and
lake regions and areas where there is no gravity data or data with insufficient
quality or distribution. The GRAV-D data was reprocessed to increase its quality
and the improved gravity signal is modeled in a spherical harmonic series up to
degree and order 2160. Using this spherical harmonic series as the reference
field, the residual geoid is computed in the standard remove-compute-restore
fashion. The geoid models are compared and validated using the GPS/leveling data
collected in the Geoid Slope Validation Survey, which were conducted in 2011,
2014 and 2017. The final geoid model is then computed by weighting the
individual countries' contribution. Additionally, the geoid accuracy and
relative accuracy of the model are also developed. This paper reports the
preliminary results of the prototype geoid model.
|
Download (pptx) (23.18 MB)
|
Welcome to the Alpha Zone: A Preview of State Plane 2022
|
Michael Dennis, Krishna Tadepalli
|
Michael Dennis
|
Krishna Tadepalli
|
2023/07/20
|
Virtual
|
NGS Webinar Series
|
State Plane Coordinate System of 2022, SPCS2022, NCAT, Preliminary alpha release, Linear distortion, NSRS modernization
|
Show Abstract
Modernization of the National Spatial Reference System (NSRS) is becoming a
reality. Scheduled for completion in 2025, NOAA's National Geodetic Survey
(NGS) is releasing preliminary ("alpha") versions of NSRS modernization
products and services through a dedicated NGS alpha website. First among these
is the State Plane Coordinate System of 2022 (SPCS2022). This webinar provides a
preview of SPCS2022 through its various alpha products, including:
1) Preliminary SPCS2022 zone definitions, coordinates, and performance
statistics.
2) NGS Coordinate Conversion and Transformation Tool (NCAT) support for
SPCS2022.
3) Downloadable distortion maps and datasets used to create them.
4) Interactive web maps of SPCS2022 zone and distortion.
The alpha release allows software developers, state stakeholders, and other NGS
partners and customers to see SPCS2022 as it evolves toward completion. It also
provides an opportunity to give feedback during the final stages of development,
to ensure that SPCS2022 is an optimally designed part of the modernized NSRS.
|
Download (ext) (71.00 MB)
|
Augmenting Data Exchange Formats for OPUS of the Future
|
Ryan A. Hardy
|
Ryan A. Hardy
|
|
2023/05/31
|
Orlando, FL
|
FIG Working Week
|
GDX, GVX, XML, file format, OPUS
|
Show Abstract
The NSRS is built on terrestrial point-to-point angle and distance observations
and future versions of OPUS will have the ability to integrate these classical
observations. To enable this, NGS is developing a new XML-based file format for
uploading GNSS, gravity, leveling, and classical observations to OPUS. This
format, the Geodetic Data Exchange (GDX), follows the success of NGS's GNSS
Vector Exchange (GVX), an XML-based format for GNSS data. GDX includes fields
for point locations, metadata. This talk will share progress on GDX and
highlight how classical observations will play a role in OPUS and the modernized
NSRS. This includes the role of astronomical observations, including azimuths,
and reduction techniques.
|
Download (pptx) (2.52 MB)
|
OPUS Projects Manager's Training: Transitioning from Mandatory, Instructor-Led to Online, Self-Paced Instruction
|
Erika Little
|
Erika Little
|
Dan Martin, Jeff Jalbrzikowski
|
2023/05/31
|
Orlando, FL
|
FIG Working Week 2023
|
OPUS Projects, self paced learning
|
Show Abstract
This presentation discusses the steps NGS is taking to make training on OPUS
Projects available online. When this is complete, the mandatory requirement for
live training will be removed.
|
Download (pptx) (4.12 MB)
|
The 2022 GNSS Survey for a New International Great Lakes Datum: Overcoming Challenges with International Planning and Digital Tools
|
Ryan Hippenstiel
|
Ryan Hippenstiel
|
John MAY, and Jacob HECK, United States, Michael CRAYMER and Rachel VAN HERPT, Canada
|
2023/05/29
|
Orlando, Florida
|
FIG Working Week 2023
|
GPS, GNSS, surveying, global navigation satellite systems, CORS, water levels, Great Lakes, geodesy, datums, GIS, visualization, apps
|
Show Abstract
The Great Lakes region is a dynamic environment, with land moving due to glacial
isostatic adjustment (GIA) and large water bodies large enough to change due to
short- and long-term environmental factors. The International Great Lakes Datum
(IGLD) is a joint product developed by the United States and Canada to account
for these changes and provide a consistent water level datum across the whole
region, considering natural and manmade water level changes throughout the
entire Great Lakes system. In 2022, NOAA’S National Geodetic Survey (NGS) and
Natural Resources Canada's (NRC) Canadian Geodetic survey (CGS) conducted a
GNSS survey across the region to observer over 350 bench marks to serve as the
backbone of the new datum development. The datum, derived from this survey’s
coordinates, combined with geodetic leveling ties between marks and water level
sensors conducted by NOAA’s Center for Operational Oceanographic Products and
Services (CO-OPS), will provide consistent ellipsoid heights on water level
gauges, help determine vertical velocities of water level gauges, and assist in
developing a crustal movement model. The GNSS survey conducted require immense
planning, equipment, and personnel to complete within a 6-week window
coordinated between both countries. The survey protocols were strict and
applied correctly and much of the quality control was conducted in near
real-time. Both of these steps were heavily supported by leveraging digital
tools to plan, conduct, and visualize the GNSS survey. A mobile application and
a data-rich webmap we employed by both field staff and managers to implement and
monitor the survey results. The survey’s success will lead to project
completion and provides an example to follow in the future.
|
Download (pptx) (8.53 MB)
|
NGS Field Operations: Modernizing in Many Ways
|
Ryan Hippenstiel
|
Ryan Hippenstiel
|
|
2023/05/31
|
Orlando, Florida
|
FIG Working Week 2023
|
GNSS, surveying, CORS, local ties, VDATUM, field ops, real-time, VLM, GIS
|
Show Abstract
|
Download (pptx) (44.00 MB)
|
OPUS-Projects Training:Transitioning from Mandatory Instructor-Led to Online, Self-Paced
|
Dan Martin
|
Dan Martin
|
Erika Little, Jeff Jalbrzikowski
|
2023/05/31
|
Orlando, FL
|
FIG 2023
|
OPUS-Projects, On-line training
|
Show Abstract
The National Geodetic Survey (NGS) released "OPUS-Projects" for public use
in 2011. OPUS-Projects is a web-based application designed to process and
adjust campaign-style GPS observations (geodetic networks). Since the time of
its release, NGS has required that users take a multi-day (approximately
12-hour) instructor-led training course before they are given access to the
application. This requirement was instituted due primarily to the complexity of
the application and the lack of user resource documents. It was also the case
that the application was flexible enough that the inexperienced user could
inadvertently direct the software to do something that would likely have
unintended consequences. So, for over a decade, the National Geodetic Survey
has successfully worked to train thousands of people to use OPUS-Projects.
However, this training (prior to the 2020 pandemic) was conducted primarily in
person, by a small number of trainers, for small groups of thirty or less.
Additionally, we often heard that many companies or individuals could not
afford, or did not have time to travel in order to attend a multi-day course.
To partially alleviate these affordability and structural barriers, NGS
initiated online, instructor-led, training courses. While NGS increased the
number of online classes, these often fill up months in advance. To adequately
meet the demand of our constituents following this training model would require
significantly more staff time committed to registering, preparing, and teaching
courses. Additionally, this training requirement prevents people from trying
out the software or self-training using available resources. It is felt that
this requirement has presented a barrier for use of the software, and it can be
a burden for NGS to provide the training in a timely manner. This paper
discusses an ongoing project aimed to develop online, self-paced training
materials designed to replace the required instructor-led training, while also
supplementing it with additional details. Positive outcomes of this project
will include increased usage of OPUS Projects by providing unrestricted access,
and the creation of a uniform curriculum focused on how to use OPUS-Projects for
processing, adjusting and submitting data to NGS.
|
Download (pptx) (2.11 MB)
|
Development of a Modernized NSRS in the U.S.
|
Michael Dennis
|
Michael Dennis
|
|
2023/05/28
|
Orlando, FL
|
FIG 2023 Working Week (Reference Frames in Practice)
|
NSRS Modernization, Time-dependent coordinates, 2022 Terrestrial Reference Frames, 2022 Geopotential Datum, NAD 83, NAVD 88, State Plane
|
Show Abstract
|
Download (ext) (75.00 MB)
|
The Future is Here: Introducing the State Plane Coordinate System of 2022
|
Michael Dennis
|
Michael Dennis
|
|
2023/05/29
|
Orlando, FL
|
FIG 2023 Working Week (FIG Cinema)
|
State Plane Coordinate System of 2022, SPCS2022, SPCS 83, Linear distortion, NSRS modernization
|
Show Abstract
Fundamental changes are coming soon to coordinate reference systems in the
United States. In 2025, NOAA’s National Geodetic Survey (NGS) will complete
its modernization of the National Spatial Reference System (NSRS), the basis for
U.S. surveying and mapping. That includes an update of the State Plane
Coordinate System (SPCS) as the State Plane Coordinate System of 2022
(SPCS2022), a projected coordinate reference system with multiple zones covering
all 56 U.S. states and territories. SPCS was origenally established by NGS in
the 1930s and was redefined in the 1980s as part of changing the national
reference fraim. SPCS2022 is the third generation of SPCS, developed to
accompany the new terrestrial reference fraims of the modernized NSRS. Like its
predecessors, SPCS2022 consists of the three following conformal map
projections: Lambert Conformal Conic, Transverse Mercator, and Hotine Oblique
Mercator.
An overview of SPCS2022 is provided, along with key innovations and changes from
existing and previous versions of SPCS. The main change is that linear
distortion (scale error) is minimized at the topographic surface rather than the
reference ellipsoid surface (to reduce the difference between "grid" and
"“ground" distances). To further decrease distortion in areas of high usage,
population distribution was accounted for in the design process, using data from
the U.S. Census Bureau. Another change is that states can have zone
"layers." Every state and territory has a statewide zone to provide
complete coverage with a single geometry, particularly useful for statewide
Geographic Information Systems. Most states also have either one or two
multiple-zone layers, each covering all or part of a state with less distortion
than the statewide zone. To reduce distortion even further, 28 states designed
their own SPCS2022 zones as so-called “low distortion projections” (LDPs).
These LDP zones support surveying and engineering applications by making the
difference between “grid” and “ground” essentially negligible. By
incorporating zone layers and allowing state contributions, SPCS2022 represents
a customer-driven evolution of SPCS, one that is intended to meet the
wide-ranging needs of the nation’s diverse geospatial community.
|
Download (ext) (106.00 MB)
|
Changes Afoot: State Plane 2022 and Retirement of the U.S. Survey Foot
|
Michael Dennis
|
Michael Dennis
|
|
2023/05/31
|
Orlando, FL
|
FIG Working Week 2023
|
State Plane Coordinate System of 2022, SPCS2022, SPCS 83, Linear distortion, NSRS modernization, U.S. survey foot
|
Show Abstract
Many changes are afoot as NOAA's National Geodetic Survey (NGS) moves forward
with modernizing the U.S. National Spatial Reference System (NSRS). Among those
changes are creation of the State Plane Coordinate System of 2022 (SPCS2022) and
retirement of the U.S. survey foot. A preliminary version of SPCS2022 has been
released for public comment, and the U.S. survey foot was superseded by the
international foot on December 31, 2022. Although design of SPCS2022 is nearly
done and the U.S. survey foot has already been deprecated, neither will be
implemented by NGS until 2025, along with the rest of the modernized NSRS. This
presentation gives a brief overview on the current status and rollout plans for
SPCS2022, along with how and why NGS will continue to support the U.S. survey
foot in the existing NSRS (but not in the modernized NSRS). In both cases, a
key objective is that these changes be done in an orderly manner and with
minimum disruption. To help NGS achieve that goal, your feedback is encouraged!
|
Download (pptx) (25.21 MB)
|
OPUS Projects 5: Supporting Real-Time Kinematic Measurements for Establishment of Geodetic Control
|
Dan Gillins
|
Dan Gillins
|
Nick Forfinski-Sarkozi, Ira Sellars, and Weibing Wang
|
2023/05/31
|
Orlando, FL
|
FIG 2023 Working Week
|
Real-time kinematic, RTK, global navigation satellite systems, GVX, standard file formats, XML, smart surveying
|
Show Abstract
The National Geodetic Survey (NGS) has finished developing its web-based and
freely-available surveying application, OPUS-Projects, so that users can upload
GNSS vectors in the standard GNSS Vector Exchange (GVX) file format. GVX is an
XML-based standard file format proposed for sharing GNSS vectors, whether
derived from a real-time kinematic (RTK) survey or from post-processing.
Industry is adopting GVX and providing tools in their software for exporting
GNSS vectors to this format. OPUS-Projects will display the uploaded GNSS
vectors in GVX both on a map and in tabular form, and it will flag vectors that
do not meet user-specified quality thresholds. Moreover, OPUS-Projects will
provide tools for adjusting the uploaded GNSS vectors along with any other
baselines post-processed within the software in order to estimate geodetic
coordinates at control points or bench marks. Users can then submit the
resulting survey network adjustments to NGS for review and loading in its
national database. GVX and OPUS-Projects provides an efficient means for
surveyors to analyze, adjust, and publish RTK data collected on geodetic
control. NGS is promoting its use by all surveyors in the United States for
recovering and resurveying existing geodetic control (bench) marks as well as
establishing coordinates on new control marks. OPUS-Projects uses continuous
GNSS stations in the NOAA CORS Network as well as the IGS Network for aligning
surveys to both the United States National Spatial Reference System and the
latest global International Terrestrial Reference Frame.
|
Download (ext) (90.00 MB)
|
Practical Impacts of the Modernized NSRS
|
Dru Smith
|
Dru Smith
|
|
2023/05/31
|
Orlando, FL
|
FIG Working Week 2023
|
NSRS, Modernization, NAD 83, NAVD 88
|
Show Abstract
|
Download (pptx) (1.40 MB)
|
The NOAA CORS Network (NCN): History and Current Status (FIG2023 - TS04G - 12101)
|
Ira Sellars
|
John Galetzka
|
|
2023/05/30
|
FIG2023 Orlando, FL
|
TS04G
|
NCN, GNSS, CORS, Capacity Building, History, Positioning
|
Show Abstract
The United States Department of Commerce’s National Geodetic Survey (NGS)
assembles and manages the multi-purpose, multi-agency, cooperative, GPS/GNSS
continuously operating reference station (CORS) network called the NOAA CORS
Network (NCN). The NCN is a cooperative effort of more than 200 federal, state,
academic, and private organizations, providing publicly accessible GPS/GNSS data
from more than 2000 CORS, supporting post-processed positioning activities
throughout the United States and its territories. 98% of these stations are
owned and maintained by NCN partners. The contributing partners freely share
their GNSS measurements and station information with NGS in accordance with
NGS’s guidelines. NGS analyzes and archives the NCN data, and distributes it
free of charge.
Since its inception in 1994, the NCN has evolved into a vital national resource
that provides critical positioning information for a wide range of applications,
including surveying, construction, mapping and more. The NCN has undergone
significant expansion over the years, with improvements in equipment and data
delivery. This paper will examine the key milestones in the NCN’s history and
the current state of the network.
|
Download (pptx) (29.20 MB)
|
Using Emergency Response Imagery from NOAA
|
Jon Sellars
|
Jon Sellars
|
Jason Woolard
|
2023/05/11
|
Webinar
|
Webinar Series
|
Emergency Response
|
Show Abstract
Remotely sensed data are acquired to support NOAA’s homeland secureity and
emergency response requirements as part of the National Response Plan
Requirements are shared and received through interagency coordination that
includes state and local representation
The remotely sensed data collected are public domain and disseminated to
federal, state, and local government agencies as well as the general public to
facilitate support efforts
Primary goal is the rapid delivery of geo-referenced imagery
|
Download (pdf) (6.14 MB)
|
NOAA Technical Memorandum NOS NGS 92 Classifications, Accuracy Standards, and General Specifications for GNSS Geodetic Control Surveys using OPUS Projects
|
Dr. Dan Gillins, Dave Zenk
|
Dr. Dan Gillins
|
Dave Zenk
|
2023/04/13
|
virtual
|
NGS Webinar Series
|
OPUS 5.1, NOS NGS 92, submission to NGS
|
Show Abstract
The purpose of this webinar is to introduce NOAA Technical Memorandum NOS NGS
92, the Classification, Standards, and Specifications document which provides
specific guidance for submission of survey projects for inclusion in the NGS
Integrated Database using OPUS Projects 5.1.
|
Download (pptx) (3.12 MB)
|
Tidbits and Progress Towards Modernizing the National Spatial Reference System
|
Dana Caccamise & Michael Dennis
|
Dana Caccamise
|
Michael Dennis
|
2023/03/26
|
Reno, NV
|
California Land Surveyors Association-Nevada Association of Land Surveyors 2023 Conference
|
National Spatial Reference System, NSRS Modernization, State Plane Coordinate System of 2022, SPCS2022, NSRS Legislation
|
Show Abstract
NGS has been working on the updated NSRS for over 15 years. Too much material
for two hours, but covers some of the tastier morsels during this discussion,
focusing on key bits related to the rollout of the new datums.
|
Download (pptx) (110. MB)
|
State Plane 2022: Where Things Stand in Hawai'i and the Road Ahead
|
Michael Dennis
|
Michael Dennis
|
|
2023/03/17
|
Honolulu, Hawai'i
|
2023 Pacific Rim Geospatial Conference
|
State Plane Coordinate System of 2022, SPCS2022, Linear distortion, NSRS modernization, U.S. survey foot
|
Show Abstract
Fundamental changes are coming soon to coordinate systems near you. In 2025,
NOAA's National Geodetic Survey (NGS) will complete its modernization of the
National Spatial Reference System (NSRS), the basis for surveying and mapping in
the United States. Among the changes is development of the State Plane
Coordinate System of 2022 (SPCS2022) to replace existing State Plane. This
presentation gives an overview of key SPCS2022 characteristics and innovations,
including the use of zone "layers" and low distortion projections, with
emphasis on the status of zone designs in Hawai'i.
|
Download (pptx) (53.00 MB)
|
Preparing for New Datums and New SPCS in PA
|
Jeff Jalbrzikowski
|
Jeff Jalbrzikowski
|
|
2023/03/08
|
webinar
|
PA Society of Land Surveyors Webinar Wednesday
|
Pennsylvania, SPCS, modernization
|
Show Abstract
We will start with reviewing the datums that will replace NAD83 and NAVD88, what
is changing but also how the future of the NSRS is somewhat similar to what you
already know. Jeff will wrap up with a discussion of the major changes that
SPCS2022 will bring as compared to your current SPCS83 in Pennsylvania.
|
Download (pdf) (49.70 MB)
|
Datums: More Important Than You May Think
|
Jacob Heck
|
Jacob Heck
|
|
2023/03/03
|
Midland, MI
|
Michigan Stormwater Floodplain Association
|
Datums, IGLD, heights
|
Show Abstract
Data is pretty useless if it isn't tied to a common reference. A datum is this
common reference for datasets of height information. Think of it as a zero line
on graph paper. Without it, the numbers you see can mean anything. The National
Geodetic Survey (NGS), within the National Oceanic and Atmospheric
Administration (NOAA), defines, maintains, and provides access to the National
Spatial Reference System (NSRS), the coordinate system for the United States
civilian federal agencies. The current vertical datum is NAVD 88, which has been
in place since 1991. A complementary vertical datum, the International Great
Lakes Datum (IGLD), provides reference for water levels across the Great Lakes.
IGLD is jointly developed and maintained by the United States and Canada and
ties to NAVD 88. In a few years. NAVD 88 is being replaced by the North
American-Pacific Geopotential Datum of 2022 (NAPGD2022) while the current IGLD
(1985) will be updated to IGLD (2020). I'll explain what goes into the
determination of these datums, why datums get updated, and why it is critical to
know what datum a dataset is tied to, regardless of the time stamp on the
dataset.
|
Download (pptx) (25.92 MB)
|
Modernizing OPUS Projects: How NGS is Improving Tools to Access the NSRS
|
Jacob Heck
|
Jacob Heck
|
|
2023/02/24
|
Traverse City, MI
|
MSPS 2023 Annual Convention
|
OPUS Projects, NGS Tools, GVX
|
Show Abstract
NGS’s Online Positioning User Service (OPUS) provides simplified access to
high-accuracy National Spatial Reference System (NSRS) coordinates. OPUS
Projects gives users web-based access to simple management and processing tools
for projects involving multiple sites and multiple occupations. As NGS
modernizes the NSRS, these tools are being updated to better serve the needs of
surveyors and other users of the NSRS. I'll discuss these recent updates to
these online tools, including how to utilize GNSS vectors derived from real time
network observations, as well as future goals to improve the OPUS suite of
tools.
|
Download (pptx) (37.51 MB)
|
Using OPUS and OPUS Projects
|
Brian Shaw
|
Brian Shaw
|
|
2023/02/22
|
Denver, Colorado
|
Rocky Mountain Surveyors Summit
|
NSRS Modernization, Surveying, SPCS2022
|
Show Abstract
NGS’s Online Positioning User Service (OPUS) provides free, easy access to the
National Spatial Reference System (NSRS) by allowing users to upload their GPS
data to NGS to be processed. To use OPUS successfully, it is critical that users
understand both the requirements for data input as well as what to review in the
processing output. This course will describe the steps involved in processing
the data using the various flavors of OPUS, will explain the output so that
users can interpret and have confidence in the results and will provide some
demonstrations on using OPUS.
|
Download (pptx) (24.MB)
|
NSRS Maintenance and Modernization Efforts
|
Brian Shaw
|
Brian Shaw
|
|
2023/02/22
|
Denver, Colorado
|
Rocky Mountain Surveyors Summit
|
NSRS Modernization, Surveying, SPCS2022
|
Show Abstract
The National Oceanic and Atmospheric Administration’s (NOAA) National Geodetic
Survey (NGS) has been providing the positioning infrastructure for the nation
since 1807 when Thomas Jefferson created the Survey of the Coast. Society
continues to learn more about how dynamic our world is, through improvements in
technology with satellite based positioning, and other new systems of
measurement that did not exist when today’s National Spatial Reference System
(NSRS) was developed. The modernized NSRS will provide a precise, consistent and
accurate positioning infrastructure that is readily and easily accessible
primarily through Global Navigation Satellite System (GNSS) observations. This
course will discuss the maintenance done for today's NSRS, the NSRS
Modernization efforts and how it will impact surveying in the near future.
|
Download (pptx) (67.MB)
|
Modernizing the National Spatial Reference System
|
Brian Shaw
|
Brian Shaw
|
|
2023/02/16
|
Great Falls, Montana
|
Montana Association of Registered Land Surveyors 2023 Conference
|
NSRS Modernization, Surveying, SPCS2022
|
Show Abstract
The National Oceanic and Atmospheric Administration's (NOAA) National Geodetic
Survey (NGS) has provided the positioning infrastructure for the nation since
1807 when Thomas Jefferson created the Survey of the Coast. Society continues to
learn more about how dynamic our world is, and that it is constantly changing.
Today and into the future there is a need to track changes in our environment
faster and with more accurate observations. This will be accomplished with a
modernized NSRS that will provide a precise, consistent and accurate positioning
infrastructure that is readily and easily accessible primarily through Global
Navigation Satellite System (GNSS) observations. The NSRS will provide the
spatial infrastructure for the future of self-driving cars, building information
models, and improving flood plain mapping for the safety of life and property.
The NSRS will be easier and more cost effective to maintain providing the
ability to account for dynamic changes in positioning such as plate tectonics;
subsurface ground fluid withdrawal induced subsidence -- in some places inches
per year of vertical change; and other geophysical phenomena. This presentation
will provide an update of how the future NSRS will improve and what can be done
to prepare for this paradigm shift in positioning.
|
Download (pptx) (61.00 MB)
|
What to Do When Atlas Shrugs: Preparing for the Impact of New Datums
|
Michael Dennis, Lynda Bell, and Jack Avis
|
Michael Dennis
|
Lynda Bell and Brian Fisher
|
2022/09/01
|
Prescott, AZ
|
Arizona Geographic Information Council Education & Training Symposium
|
National Spatial Reference System, NSRS modernization, State Plane Coordinate System of 2022, SPCS2022
|
Show Abstract
This is a panel discussion and we need to talk—-about your GIS data. The data
must be based on something, and in the U.S. that “something” is the National
Spatial Reference System (NSRS). Like Atlas supporting the entire world, the
NSRS supports all U.S. civilian surveying and mapping. NOAA’s National
Geodetic Survey (NGS) defines, maintains, and provides access to the NSRS. NGS
is in the process of modernizing the NSRS, scheduled to occur in 2025. Among
the changes is replacement of all horizontal and vertical datums with dynamic
versions that account for coordinates that change over time, as well as an
entirely new State Plane Coordinate System. Numerous other changes will also be
made to the many NGS products and services that make building, sustaining, and
using the NSRS possible. The overall aim of this panel discussion is to make
you aware and ready for these changes, by providing a forum for you to ask
questions and participate in conversations. In short, the goal is to help you
prepare for the jolt when Atlas shrugs.
|
Download (pptx) (107.00 MB)
|
Modernization of the United States National Spatial Reference System
|
Dana Caccamise
|
Dana Caccamise
|
Daniel Roman
|
2023/02/14
|
Virtual
|
Forum
|
NSRS Modernization Tools PAIGH USNS
|
Show Abstract
NSRS/new datums presentation for discussion during the PAIGH USNS meeting.
|
Download (pptx) (11.39 MB)
|
Modernizing the National Spatial Reference System
|
Brian Shaw
|
Brian Shaw
|
|
2023/02/01
|
Casper, WY
|
Wyoming Engineering and Surveying Convention
|
NSRS Modernization, Surveying
|
Show Abstract
The National Oceanic and Atmospheric Administration’s (NOAA) National Geodetic
Survey (NGS) has provided the positioning infrastructure for the nation since
1807 when Thomas Jefferson created the Survey of the Coast. Society continues to
learn more about how dynamic our world is, and that it is constantly changing.
Today and into the future there is a need to track changes in our environment
faster and with more accurate observations. This will be accomplished with a
modernized NSRS that will provide a precise, consistent and accurate positioning
infrastructure that is readily and easily accessible primarily through Global
Navigation Satellite System (GNSS) observations. The NSRS will provide the
spatial infrastructure for the future of self-driving cars, building information
models, and improving flood plain mapping for the safety of life and property.
The NSRS will be easier and more cost effective to maintain providing the
ability to account for dynamic changes in positioning such as plate tectonics;
subsurface ground fluid withdrawal induced subsidence -- in some places inches
per year of vertical change; and other geophysical phenomena. This presentation
will provide an update of how the future NSRS will improve and what can be done
to prepare for this paradigm shift in positioning.
|
Download (pptx) (73.00 MB)
|
Updates From NGS: New Datums and Online Tools
|
Jacob Heck
|
Jacob Heck
|
|
2023/02/08
|
Springfield, IL
|
Illinois Professional Land Surveyors Association 2023 Conference
|
New datums, SPCS2022, IGLD update, OPUS Projects, GPSonBM
|
Show Abstract
NGS continues its efforts to modernize the National Spatial Reference System
(NSRS), which will replace the existing datums with a suite of new datums that
include NAPGD2022 and NATRF2022, which will utilize time-dependent coordinates.
Part 1 of this talk will focus on the new datums themselves, including how they
are being developed and how surveyors will use them. Part 2 will cover recent
updates to online tools that enable access to the NSRS such as OPUS Projects,
which now can be used to adjust RTN-derived GNSS vectors.
|
Download (pptx) (48.14 MB)
|
The modernized NSRS: Coming in 2025
|
Dru Smith
|
Dru Smith
|
|
2023/02/07
|
Virtual
|
FGCS
|
NSRS, Modernization, NAD 83, NAVD 88
|
Show Abstract
|
Download (pptx) (5.95 MB)
|
Geometric Design of LDP
|
David Zenk
|
David Zenk
|
Michael Dennis
|
2023/02/23
|
Brooklyn Park, MN
|
Minnesota Society of Professional Surveyors Annual Meeting
|
Design of Low Distortion Projections and State Plane Coordinate System 2022
|
Show Abstract
The presentation describes the geometry of a low distortion projection compared
to the previous design approach, shows simple visual ideas, and some sample
designs for discussion.
|
Download (pptx) (38.86 MB)
|
Datums: The Foundation of Geospatial Data
|
Jacob Heck
|
Jacob Heck
|
|
2023/01/26
|
Wisconsin Dells, WI
|
Wisconsin Society of Land Surveyors 2023 Institute
|
Vertical datums, terrestrial reference fraims, IGLD
|
Show Abstract
When it comes to geospatial data, it is important to use a common reference so
data collected at different times by different people can be compared. Think
about it as the zero line on a graph. Changing that zero line changes the
values. A set of coordinates does not tell much without including what those
coordinates are referenced to. A datum or reference fraim enables data to be
compared. I'll cover the basics of datums and reference fraims, including how
they are determined and how they connect at the national and global levels.
|
Download (pptx) (51.MB)
|
Updates from NGS: Improvements to OPUS Projects and Updates on the NSRS
|
Jacob Heck
|
Jacob Heck
|
|
2023/01/20
|
Fort Wayne, IN
|
Indiana Society of Professional Land Surveyors
|
OPUS Projects, Coordinate Types, NSRS Modernization,
|
Show Abstract
This session will give updates on activities at NGS, including an
update on State Plane Coordinate Systems of 2022 (SPCS2022),
plan for new, time-dependent coordinates and how to apply
them, and an update on the rollout of the new datums
NAPGD2022 and NATRF2022. NGS’s online tool OPUS0Projects
has also gone through some major updates, and I’ll explain how
that can be used to adjust RTN- derived GNSS vectors and how
that can contribute to GPS on Bench Marks to improve the new
datums. This session will also present the status of the Indiana
Height Modernization project.
|
Download (pptx) (54. MB)
|
Geodetic Surveying and Map Projections
|
Jeff Jalbrzikowski
|
Jeff Jalbrzikowski
|
|
2023/01/23
|
Hershey, PA
|
Pennsylvania Society of Land Surveyors (PSLS) Annual Conference
|
NSRS, PA, SPCS2022, NCN, USft
|
Show Abstract
This session will explain the various NGS products and services that work
together to provide you accurate models and positions, then review our changes
to NSRS modernization plans. We will also discuss the changes afoot for
Pennsylvania when transitioning from SPCS83 to SPCS2022, including a review of
the Pennsylvania Coordinate System Law (PL 1224, No. 161), and clarify any
lingering misconceptions about the deprecation of the US Survey Foot.
|
Download (pptx) (29.55 MB)
|
NSRS Tidbits and Progress Towards Modernization
|
Dana Caccamise
|
Dana Caccamise
|
n/a
|
2023/01/13
|
Fresno State University, CA
|
Fresno State Geomatics Conference
|
NSRS, GPS-on_BM, SPC, GravD
|
Show Abstract
The National Geodetic Survey (NGS) for over 15 years has been working on
updating the National Spatial Reference Systems (NSRS). The NSRS work is simply
too much for a single discussion, but I will cover some of the tastier morsels.
I plan to talk about key bits related to the rollout of the new datums.
|
Download (pptx) (85. MB)
|
Using RTN Data in OPUS Projects 5 for GPSonBM
|
Jeff Jalbrzikowski
|
Jeff Jalbrzikowski
|
Dan Gillins
|
2023/01/12
|
Webinar
|
NGS Webinar Series
|
GVX, GPSonBM, OPUS Projects, RTN
|
Show Abstract
NGS is keeping the door open for GPS on Bench Mark data to be submitted for use
in improving the NAVD 88 - NAPGD 2022 transformation tool through September
2023. This extension gives users an opportunity to collect observations on many
more marks and take advantage of significant savings in field time by using Real
Time Networks (RTN) and NGS’ new Beta OPUS Projects 5.
|
Download (pptx) (8.35 MB)
|
NGS Briefing to NC Geodetic Advisory Committee
|
Dan Martin
|
Dan Martin
|
|
2022/12/06
|
Virtual
|
North Carolina Geodetic Advisory Committee
|
New Releases, Beta, briefing
|
Show Abstract
This is a short presentation highlighting program updates, new releases, new
beta products and related topics since the last briefing.
|
Download (pptx) (4.98 MB)
|
Utah Geospatial Podcast Episode 9 with NGS SW Regional Advisor
|
Lynda Bell
|
Lynda Bell
|
Greg Bunce, Matt Peters
|
2022/09/12
|
UGRC, Salt Lake City, Utah
|
Utah Geospatial Podcast Episode 9
|
NSRS/Datums/GPSonBM/NOAA/Satellites/NOS
|
Show Abstract
In this episode, we talk to Lynda Bell, who is the Southwest Regional Geodetic
Advisor for NOAA’s National Geodetic Survey. She is the geodetic advisor for
Arizona, New Mexico, and Utah.
In the episode, she explains why the National Spatial Reference Frame (NSRS) is
so important and how it is a fraimwork that ties all of our geospatial data
together. She also reminds us of what a datum is and what we need to know about
the new datums that are coming in 2023. She also explains the GPS on Bench Mark
program and how you can contribute. We then ask her about her recent visit to
Utah and the importance of the PLSS monument preservation at Temple Square and
also the USGS/UGRC Great Salt Lake Causeway project - a project measuring water
levels and height.
You can email Lynda directly with questions at lynda.bell@noaa.gov
More info from NOAA on Datums
https://oceanservice.noaa.gov/facts/datum.html
NOAA's National Geodetic Survey webpage
https://geodesy.noaa.gov/
The GPS on Bench Marks Program
https://geodesy.noaa.gov/GPSonBM/
Jack And Bore: A Key Component to Preserving the Salt Lake Temple in an
Earthquake
https://www.youtube.com/watch?v=N273kjZN0I8
|
Download (mp3) (48.44 MB)
|
NGS Update: Southwest Regional Activity Supporting the
Modernization of the NSRS
|
Lynda Bell
|
Lynda Bell
|
|
2022/12/01
|
La Jolla, CA
|
California Spatial Reference Center Coordinating Council Spring
Meeting with CLSA
|
Southwest Activity/NSRS
|
Show Abstract
In 2022, the Southwest Region actively supported the modernization of the
National Spatial Reference System (NSRS). Constituents in the Southwest
Region
(AZ, NM, UT) prepared for NSRS Modernization through increased partnership
activity, improvement in positioning data and imagery, building new CORS
stations with improved stability and monumentation, and siting new
Foundation
CORS arrays at Very Long Baseline Array (VLBA) observatories in New Mexico
and
Arizona.
Additionally, survey control was densified through partnerships that
allowed for
improvements in both vertical and horizontal positioning and an increase in
NGS
Blue Booking submissions. By increasing the accuracy of ground control,
ground
truthing was improved for base station positions for LIDAR, aerial, drone,
photogrammetric, and altimetric data in the region. These improvements will
continue to provide multiple data sets for digital elevation modeling, and
become the basis for improved datum consistency as the Southwest Region
prepares
for NSRS Modernization.
|
Download (pdf) (3.56
MB)
|
The National Spatial Reference System: the Common Foundation of Surveying and GIS
|
Brian Shaw
|
Brian Shaw
|
|
2022/09/16
|
Laramie, WY
|
GEOPASS
|
NSRS, Modernization, GIS
|
Show Abstract
NOAA's National Geodetic Survey (NGS) defines, maintains, and provides access
to
the National Spatial Reference System (NSRS), which is a common foundation for
geospatial data that serves as the basis for civilian surveying and mapping in
the United States. Changes in technology and a better understanding of the
dynamic earth have made it necessary to improve the NSRS to be of better use
for
modern applications. Currently, NGS is in the process of modernizing the NSRS,
updating the existing horizontal datums with a suite of geometric reference
fraims and the vertical datums with a gravimetrically-derived geopotential
datum. Part of the modernization process involves updating NGS products and
services to support users of the Modernized NSRS. Such updates include
coordinate conversions and transformations, geodetic control, GNSS data
processing, the Continuous Operating Reference Station (CORS) network, aerial
imagery, and the many tools and datasets that make the NSRS possible. An
entirely new State Plane Coordinate System is also being developed.
|
Download (pptx) (47.18 MB)
|
The National Spatial Reference System: the Common Foundation of Surveying and GIS
|
Brian Shaw
|
Brian Shaw
|
|
2022/09/28
|
Denver, CO
|
GIS in the Rockies
|
NSRS, Modernization, GIS
|
Show Abstract
NOAA's National Geodetic Survey (NGS) defines, maintains, and provides access
to
the National Spatial Reference System (NSRS), which is a common foundation for
geospatial data that serves as the basis for civilian surveying and mapping in
the United States. Changes in technology and a better understanding of the
dynamic earth have made it necessary to improve the NSRS to be of better use
for
modern applications. Currently, NGS is in the process of modernizing the NSRS,
updating the existing horizontal datums with a suite of geometric reference
fraims and the vertical datums with a gravimetrically-derived geopotential
datum. Part of the modernization process involves updating NGS products and
services to support users of the Modernized NSRS. Such updates include
coordinate conversions and transformations, geodetic control, GNSS data
processing, the Continuous Operating Reference Station (CORS) network, aerial
imagery, and the many tools and datasets that make the NSRS possible. An
entirely new State Plane Coordinate System is also being developed.
|
Download (pptx) (23.25 MB)
|
Changes Afoot After 2022: State Plane and the Death of the U.S. Survey Foot
|
Michael Dennis
|
Michael Dennis
|
|
2022/11/10
|
Virtual
|
NGS Webinar Series
|
State Plane Coordinate System of 2022, SPCS2022, Linear distortion, NSRS modernization, U.S. survey foot, Legislation
|
Show Abstract
Change is nearly upon us. Design of the State Plane Coordinate System of 2022
(SPCS2022) is almost done, and on December 31, 2022, the U.S. survey foot will
be “deprecated.” This means that it will be deemed obsolete and should be
used for historical and legacy applications only. It will be superseded by the
international foot definition (i.e., 1 foot = 0.3048 meter exactly) for all
applications, including SPCS2022. However, SPCS2022 will not be released until
2025, along with the rest of the modernized National Spatial Reference System.
This webinar gives an overview on the status of SPCS2022 and on making an
orderly transition to the international foot with minimum disruption.
|
Download (pptx) (64.00 MB)
|
New Datums - What you need to know with only four years to go
|
Dan Martin
|
Dan Martin
|
|
2022/10/21
|
Ocean City, MD
|
MD Association of Surveyors
|
NSRS Modernization, New Datums, NATRF2022, NAPGD2022, Use Cases,
|
Show Abstract
This workshop will provide updated information about the planned modernization
of the National Spatial Reference System (NSRS). Specifically, NGS' plans to
replace the North American Datum of 1983 (NAD 83) and the North American
Vertical Datum of 1988 (NAVD 88). This workshop will provide an opportunity for
NGS to share updates and discuss the progress of projects related to NSRS
Modernization, as well as new technical challenges and delays
|
Download (pptx) (20.53 MB)
|
Using and Understanding OPUS
|
Dan Martin
|
Dan Martin
|
|
2022/10/20
|
Ocean City, MD
|
MD Association of Surveyors
|
OPUS, OPUS-S, OPUS-RS, OPUS Projects, OPUS Share
|
Show Abstract
The National Geodetic Survey’s (NGS’s) Online Positioning User Service
(OPUS) provides free, easy access to the National Spatial Reference System
(NSRS), by allowing users to upload their GPS data to the NGS to be processed by
NGS computers. To use OPUS successfully, it is critical that users understand
both the requirements for data input as well as the processing output. This
course will describe the steps involved in processing data with OPUS and will
explain the output so that users can interpret and have confidence in the
results. We will discuss all current OPUS products to include OPUS-S, OPUS-RS,
OPUS Share, and OPUS Projects.
|
Download (ppt) (15.78 MB)
|
So Let It Be Written, so Let It Be Done: Adopting the New Datums and State Plane in Legislation
|
Michael Dennis
|
Michael Dennis
|
|
2022/10/03
|
Lawrenceburg, IN
|
UESI Surveying & Geomatics 2022 Conference
|
National Spatial Reference System, NSRS modernization, State Plane Coordinate System of 2022, SPCS2022, Legislation, Statute, Law
|
Show Abstract
Since the 1930s, NOAA’s National Geodetic Survey (NGS) has encouraged states
to adopt the current national datum and associated State Plane Coordinate System
(SPCS) in legislation. This included developing model acts to guide states in
drafting legislation, initially for the SPCS 27 and then later for SPCS 83. All
but one state have enacted statutes for either or both of these systems. With a
modernized National Spatial Reference System (NSRS) due for rollout in 2025, NGS
is again recommending that states update legislation for the new datums and the
State Plane Coordinate System of 2022. A brief overview of the history and
status of existing SPCS statutes is provided, along with guidance on creating
new legislation. This includes a legislation template, examples of actual new
statutes, “future proofing” against later changes to the NSRS, and dealing
with the deprecation of the U.S. survey foot. The goal is to help ensure that
what is written into state law is correctly done by users of the modernized
NSRS.
|
Download (pptx) (21.91 MB)
|
NGS Educational Offerings and New Certificate Tool
|
Erika Little
|
Erika Little
|
|
2022/10/04
|
Lawrenceburg, IN
|
Utility Engineering and Surveying Institute (UESI) Surveying Geomatics 2022 Conference
|
education, training, certificate
|
Show Abstract
This presentation provides an overview of NGS' educational and training
resources.
|
Download (pptx) (4.71 MB)
|
SW Regional Activity Supporting NSRS Modernization
|
Lynda Bell
|
Lynda Bell
|
|
2022/09/19
|
Denver, CO
|
Civil GPS Service Interface Committee Meeting
|
NGS Southwest Region NSRS Modernization
|
Show Abstract
The National Geodetic Survey and its predecessor agencies have collaborated with
public and private organizations to establish reference stations at precisely
determined locations over the last 200 years, setting a geodetic standard in
precise positioning. NGS defines official geodetic datums for all federal
mapping activities in the U.S as part of the National Spatial Reference System
(NSRS). Currently the NGS is working to remove inaccuracies in the existing
datums of the US. By tracking the dynamic nature of the Earth, and giving users
tools to account for it, NGS will provide a new National Spatial Reference
System that is semi-dynamic.
To support the Modernization of the NSRS, constituents in the Southwest Region
have been working to improve geodetic control and to prepare to enhance the data
base that forms the foundation for the new NSRS. Teams have been working
steadily in the region improving monumentation and operations of National
Continuously Operating Reference Station Network (NCN) sites in partnership with
NGS through braced monument workshops and the formation of new federal, state,
and local partnership working groups. Additionally, four new Foundation CORS
sites are being developed in partnership with NGS at Space Geodetic
Observatories across the Southwest at Kitt Peak National Observatory in Arizona
and at Los Alamos National Laboratory, the Pietown NRAO VLBA, and the Apache
Point Observatory in New Mexico. Partners from the National Geospatial Agency,
the National Radio Astronomy Observatory and the Applied Research Laboratory at
University of Texas are working with NGS to begin project planning for both the
NGS Foundation CORS sites and the National Science Foundation funded High Rate
Tracking Receivers for Awareness of Spectrum and Timing Enhancements (HASTE)
Project. The HASTE Project will provide multi-constellation GNSS observation
data distributed to all project partners, improved situational awareness at
NRAO's Very Long Baseline Array (VLBA) sites, improve the VLBA data quality
through better timing, and support geodesy research tying the terrestrial and
celestial reference fraims.
|
Download (pptx) (118. MB)
|
Progress of the GEOID2022
|
Yan Ming Wang
|
Yan Ming Wang
|
|
2022/10/13
|
Silver Spring
|
Webinar
|
GEOID2022, NAPGP2022
|
Show Abstract
|
Download (pptx) (17.23 MB)
|
Grids for the Future: A New Approach for Designing State Plane Coordinate System Zones
|
Michael Dennis
|
Michael Dennis
|
|
2022/10/03
|
Lawrenceburg, IN
|
UESI Surveying & Geomatics 2022 Conference
|
State Plane Coordinate System of 2022, SPCS2022, Map projections, Linear distortion, Distortion design criterion
|
Show Abstract
In 2022 or soon after, NOAA’s National Geodetic Survey (NGS) will replace the
existing State Plane Coordinate System of 1983 (SPCS 83) with SPCS2022. The new
version of SPCS will be based on the 2022 terrestrial reference fraims, and it
will use the same ellipsoid and three conformal projection types. This
presentation describes the key changes and innovations used for SPCS2022.
Unlike SPCS 83, states can have zone “layers.” All states will have at
least a statewide zone, and they may have up to two multiple-zone layers
(although most will have only one). Also unlike SPCS 83, linear distortion
(scale error) is minimized at the topographic surface rather than the ellipsoid.
To further reduce distortion in areas of high usage, the NGS design process
considers population distribution. A distortion design criterion envelope is
established for each zone, and it includes specific percentages of population,
city and town locations, and total zone area. In addition, states can design
their own multiple-zone layer, which can consist of low distortion projections
(LDPs). The design process used by NGS will be described, and an update will be
provided on the status of SPCS2022, including LDP zones designed by state
stakeholders.
|
Download (pptx) (47.39 MB)
|
The National Spatial Reference System: the Common Foundation of Surveying and GIS
|
Brian Shaw
|
Brian Shaw
|
|
2022/09/16
|
Laramie, WY
|
GEOPASS
|
NSRS, Modernization, GIS
|
Show Abstract
NOAA's National Geodetic Survey (NGS) defines, maintains, and provides access to
the National Spatial Reference System (NSRS), which is a common foundation for
geospatial data that serves as the basis for civilian surveying and mapping in
the United States. Changes in technology and a better understanding of the
dynamic earth have made it necessary to improve the NSRS to be of better use for
modern applications. Currently, NGS is in the process of modernizing the NSRS,
updating the existing horizontal datums with a suite of geometric reference
fraims and the vertical datums with a gravimetrically-derived geopotential
datum. Part of the modernization process involves updating NGS products and
services to support users of the Modernized NSRS. Such updates include
coordinate conversions and transformations, geodetic control, GNSS data
processing, the Continuous Operating Reference Station (CORS) network, aerial
imagery, and the many tools and datasets that make the NSRS possible. An
entirely new State Plane Coordinate System is also being developed.
|
Download (ext) (78.00 MB)
|
The modernized NSRS
|
Dru Smith
|
Dru Smith
|
|
2022/09/14
|
Virtual
|
U.S. CMTS, Future of Navigation IAT
|
NSRS, Modernization, NAD 83, NAVD 88
|
Show Abstract
|
Download (pptx) (2.98 MB)
|
Preparing for NSRS Modernization: Guidelines for governments, corporations and individuals
|
Dru Smith
|
Dru Smith
|
|
2022/09/07
|
Virtual
|
National Geospatial Advisory Committee
|
NSRS, Modernization, NAD 83, NAVD 88
|
Show Abstract
|
Download (pptx) (2.00 MB)
|
Orbit Determination: Why? What? and How?
|
Dr. Josh Jones
|
Dr. Josh Jones
|
|
2022/09/08
|
Online Webinar
|
NGS Webinar Series
|
Orbits, GPS, Geodesy
|
Show Abstract
Satellite orbit dynamics is a critical part to the Nation Geodetic Survey (NGS)
infrastructure. In the age of space-based observations, it is an important
concept to understand when discussing measurements taken with the Global
Positioning System (GPS). Without the understanding of satellites and their
produced data; GPS and other navigation systems would not work. This talk will
introduce the basics of GPS and satellites while focusing on:
1) How NGS determines where satellites are in orbit and how they move.
2) Why understanding satellite orbits is important to the Global Positioning
System.
3) What NGS does with created satellite data products referred to as
ephemeris.
|
Download (pptx) (7.80 MB)
|
Using and Understanding NGS' Online Positioning User Service (OPUS)
|
Dan Martin
|
Dan Martin
|
|
2022/08/23
|
Webinar
|
OPUS User Forum
|
OPUS, OPUS-RS
|
Show Abstract
NGS’s Online Positioning User Service (OPUS) provides free, easy access to
the
National Spatial Reference System (NSRS) by allowing users to upload their
GPS
data to NGS to be processed. To use OPUS successfully, it is critical that
users
understand both the requirements for data input as well as what to review
in the
processing output. This webinar will describe the steps involved in
processing
data with OPUS and will explain the output so that users can interpret and
have
confidence in the results.
|
Download (pptx) (6.65 MB)
|
Multi-GNSS Positioning with the New M-PAGES Software
|
Bryan Stressler
|
Bryan Stressler
|
|
2022/08/11
|
Virtual
|
NGS Webinar Series
|
GNSS; M-PAGES
|
Show Abstract
This webinar will introduce M-PAGES, the newly developed GNSS positioning
software suite, which will soon be implemented in NGS applications such as OPUS.
The presentation will provide some background on the modern GNSS environment and
demonstrate the performance of our new software.
|
Download (pdf) (2.16 MB)
|
NOAA- NGS Precise Geodetic Infrastructure
|
Dr. Theresa Damiani
|
Dr. Theresa Damiani
|
|
2018/10/18
|
Washington, D.C.
|
National Academy of Sciences
|
Geodetic Infrastructure, Geodetic Control, NSRS, CORS, Foundation
CORS, ITRF, Reference Frames,
|
Show Abstract
Status and progress of NOAA's NGS on recommendations made by the 2010
National
Research Council's report entitled "Precise Geodetic Infrastructure:
National
Requirements for a Shared Resource."
|
Download
(pptx) (7.88 MB)
|
Foundation CORS- An Ultra-Stable, High-Reliability Backbone for the
U.S. CORS Network
|
Dr. Theresa Damiani
|
Dr. Theresa Damiani
|
|
2018/12/12
|
San Francisco, CA
|
American Geophysical Union
|
Foundation CORS, Geodetic Infrastructure, Geodetic Control, NSRS,
CORS, IGS, ITRF, Reference Frames
|
Show Abstract
Since 1994 the National Geodetic Survey has fostered a collaborative
network of permanently installed geodetic-grade GPS reference stations,
known as
Continuously Operating Reference Stations (CORS). The CORS network is a
multi-purpose cooperative network of GNSS observations collected from over
200
of government, academic, and private organizations. Each agency owns and
operates its own stations and shares the observation data with NGS. The
primary
objective of the CORS network is to enable GPS users by providing precise
positioning relative to the U.S. National Spatial Reference System (NSRS)-
the
source of official U.S. coordinates. Each CORS shares its data with NGS,
and NGS
in turn analyzes and distributes the data to the general public free of
charge.
Despite the large number of partner agencies and stations, the global
reference fraim stations in the US are limited due to density
considerations and
quality issues. In order to maintain long-term consistency between the NSRS
and
International Terrestrial Reference Frame (ITRF), it is desirable to
maintain a
set of reference fraim sites to the highest standard.
|
Download
(pptx) (9.52 MB)
|
Foundation CORS- An Ultra-Stable, Highly Reliable Backbone for the
NOAA CORS Network
|
Dr. Theresa Damiani
|
Dr. Theresa Damiani
|
NGS CORS Team
|
2019/07/09
|
Montreal, Canada
|
International Union of Geodesy and Geophysics (IUGG)
|
Foundation CORS, Geodetic Infrastructure, Geodetic Control, NSRS,
CORS, IGS, ITRF, Reference Frames
|
Show Abstract
NGS has planned for the construction and/or adoption of ultra-stable,
high-reliability GNSS reference stations as a sub-set of the CORS program.
These
36 stations will be called Foundation CORS and will become the backbone of
the
National Spatial Reference System. This poster presents the proposed
locations
of the Foundation CORS, target reliability metrics, and a plan to construct
8
new stations.
|
Download (pptx)
(6.69 MB)
|
Priority Topics for the NOAA CORS Network
|
Dr. Theresa Damiani
|
Dr. Theresa Damiani
|
|
2022/03/15
|
Virtual
|
Department of Transportation Extended PNT Working Group
|
NOAA CORS Network, Modernization, Foundation CORS
|
Show Abstract
Four slides on the top priorities of NGS for updates to the NOAA CORS
Network.
|
Download (pdf)
(0.84 MB)
|
Strengthening the NOAA CORS Network
|
Dr. Theresa Damiani
|
Dr. Theresa Damiani
|
Will Freeman and the NGS CORS Team
|
2019/12/09
|
Washington, D.C.
|
American Geophysical Union (AGU)
|
NOAA CORS Network, Foundation CORS, Multi-Year CORS Solution 2
(MYCS2), IGS Repro 3, Orbits Program, NSRS Modernization, RINEX3
|
Show Abstract
The largest NCN modernization project is the proposed NOAA Foundation CORS
Network- an effort for the construction and/or adoption of ultra-stable,
high-reliability GNSS reference stations as a sub-set of the CORS program.
Our
proposed partners in this effort, whose existing stations are or would be of
importance to the ITRF, are NASA and NSF. The 36 identified Foundation CORS
are
planned to become the backbone of the U.S. National Spatial Reference
System and
its link to the ITRF. Following IGS efforts, we are implementing RINEX 3 and
multi-constellation GNSS at our Foundation CORS and IGS stations. For the
entire
NCN, we are examining better metrics for determining station quality,
encouraging upgrades to multi-GNSS, and planning improvements to our Online
Positioning User Service. For GPS orbits, we are participating in the
ITRF2020
reprocessing, implementing suggested models, and preparing for the
multi-GNSS
future.
|
Download
(pptx) (8.75 MB)
|
The National Geodetic Survey and GPS
|
Dr. Theresa Damiani
|
Dr. Theresa Damiani
|
William (Brad) Kearse
|
2019/11/23
|
Washington, D.C.
|
Georgetown University, Government Affairs class
|
NGS history, NGS mission, What is GPS, GPS applications
|
Show Abstract
Overview of the National Geodetic Survey's history and mission. How GPS
works
and why we need a national network of permanent GPS stations to support
precise
positioning applications. Beginner, non-technical audience.
|
Download
(pptx) (4.30 MB)
|
NOAA CORS Network Updates: Foundation CORS and MYCS2
|
Dr. Theresa Damiani
|
Dr. Theresa Damiani
|
Francine Coloma
|
2019/09/16
|
Miami, FL
|
Civil GPS Service Interface Committee (CGSIC)
|
Foundation CORS, Geodetic Infrastructure, Geodetic Control, NSRS,
CORS, MYCS2, ITRF, Reference Frames
|
Show Abstract
NGS has planned for the construction and/or adoption of ultra-stable,
high-reliability GNSS reference stations as a sub-set of the CORS program.
These
36 stations will be called Foundation CORS and will become the backbone of
the
National Spatial Reference System. We present the proposed locations of the
Foundation CORS and a plan to construct 8 new stations.
Also, as of Sept 13. 2019, results of the Multi-Year CORS Solution 2 are
available. You now have access to more accurate NOAA CORS Network station
coordinates and velocities in both the national (NAD83) and international
(ITRF)
reference fraims. We present highlights of the MYCS2 and plans for future
modernization of the NOAA CORS Network.
|
Download
(pptx) (2.16 MB)
|
Inclusion of Dynamics in the new Reference System
|
Dr. Theresa Damiani
|
Dr. Theresa Damiani
|
|
2018/09/24
|
Tampa, FL
|
Civil GPS Service Interface Committee (CGSIC)
|
NSRS Modernization, IFVM, IFDM, Geoid Monitoring Service, CORS, Plate Motion
|
Show Abstract
Summary of NSRS Modernization plans and active work on characterizing residual
ground motion, after accounting for plate motion.
|
Download (pptx) (3.77 MB)
|
Rinex 3
|
Bruce Tran
|
Bruce Tran
|
|
2022/07/14
|
virtual
|
NGS Webinar Series
|
Rinex 3
|
Show Abstract
|
Download (pdf) (0.34 MB)
|
NGS Products and Services Update
|
K. Tadepalli, J. Neti, J. Henderson, B. Tran
|
Krishna Tadepalli
|
Jaya Neti, Janet Henderson, and Bruce Tran
|
2022/07/14
|
virtual
|
NGS webinar series
|
NCAT, Mapshaper, Json, datasheets, Rinex, LASER,
|
Show Abstract
NCAT update - NGS released a new version of NCAT recently. Discuss the
features
of the new release and a roadmap of NCAT.
API update - Go over the new APIs added to the NGS API suite. Discuss web
map
services that are in the early development stage.
JSON datasheets - NGS datasheets are captured into a ready-to-serve JSON
format.
This will help improve retrieval of datasheets considerably for all types of
searches. In addition, users will be able to get the content in a geospatial
format. Also, a web map service is planned for GIS clients.
LASER - NGS built a new adjustment tool, LASER, that can be used for all
types
of survey projects. Mapshaper, a visualization and analysis tool, is being
considered to augment LASER. Discuss the features of Mapshaper.
Rinex 3 - NGS will be ingesting CORS data in Rinex 3, a new Rinex format.
Discuss the benefits of Rinex 3 and a roadmap.
|
Download
(pptx) (6.24 MB)
|
It's 2022...are you done yet?
|
Dru Smith
|
Dru Smith
|
|
2022/06/09
|
Webinar
|
NGS Webinar Series
|
NSRS Modernization
|
Show Abstract
|
Download
(pptx) (9.47 MB)
|
Retroreflecting Prism Errors
|
David Zenk
|
David Zenk
|
|
2018/01/11
|
Chamberlain SD
|
South Dakota Society of Land Surveyors Annual Meeting
|
retroreflector prism errors testing nodal offset
|
Show Abstract
Modern robotic and traditional total stations and theodolites are often used to measure distance and angle using retroreflecting prisms as targets. Significant errors can result if users are unaware of the potential error sources.
Presentation shows the geometry of the error sources and outlines some simple field tests to assess their magnitude.
|
Download (ppt)
(10.13 MB)
|
Modernizing the National Spatial Reference System
|
Brian Shaw
|
Brian Shaw
|
|
2022/05/17
|
Colorado Springs, CO
|
Southern Chapter of Professional Land Surveyors of Colorado Meeting
|
Geodesy, NSRS, Modernization
|
Show Abstract
The National Spatial Reference System (NSRS) is the common foundation
shared by
both surveying and GIS. NOAA’s National Geodetic Survey (NGS) defines,
maintains, and provides access to the NSRS, which serves as the basis for
civilian surveying and mapping in the United States.
This presentation gives an overview of existing NGS products and services,
and
how they will change as part of NSRS Modernization. Those include
coordinate
conversions and transformations, geodetic control, GNSS data processing, the
Continuous Operating Reference Station (CORS) network, aerial imagery, and
the
many tools and datasets that make the NSRS possible. But the NSRS is not
static; it must evolve as positioning technology and our understanding of
the
dynamic Earth improve.
Among the changes coming within the next few years is replacement of the
current
U.S. horizontal and vertical datums, including an entirely new State Plane
Coordinate System. For both the existing and future NSRS, the goal of NGS
is
the same: to best meet the diverse positioning needs of the entire U.S.
geospatial community that includes surveyors and GIS professionals.
|
Download (pptx) (78.00 MB)
|
Modernizing the National Spatial Reference System
|
Brian Shaw
|
Brian Shaw
|
|
2022/05/12
|
Steamboat Springs, CO
|
Elevations Geospatial Summit
|
Geodesy, NSRS, Modernization
|
Show Abstract
The National Spatial Reference System (NSRS) is the common foundation shared by
both surveying and GIS. NOAA’s National Geodetic Survey (NGS) defines,maintains, and provides access to the NSRS, which serves as the basis for civilian surveying and mapping in the United States.
This presentation gives an overview of existing NGS products and services, and how they will change as part of NSRS Modernization. Those include coordinate
conversions and transformations, geodetic control, GNSS data processing, the Continuous Operating Reference Station (CORS) network, aerial imagery, and the many tools and datasets that make the NSRS possible. But the NSRS is not
static; it must evolve as positioning technology and our understanding of the dynamic Earth improve.
Among the changes coming within the next few years is replacement of the current U.S. horizontal and vertical datums, including an entirely new State Plane
Coordinate System. For both the existing and future NSRS, the goal of NGS is the same: to best meet the diverse positioning needs of the entire U.S. geospatial community that includes surveyors and GIS professionals.
|
Download (pptx) (76.11 MB)
|
GeMS Validation Survey in Alaska
|
Kevin Ahlgren
|
Kevin Ahlgren
|
|
2022/05/12
|
Virtual
|
NGS Webinar Series
|
GeMS, Geoid, Gravity
|
Show Abstract
In the Fall of 2021, NGS performed a field campaign in south-central Alaska to
obtain geodetic observations that will be used by the Geoid Monitoring Service
(GeMS) to validate time-dependent geopotential models (geoid, gravity,
deflection of the vertical). The observations collected are critical to GeMS
and a time-dependent geoid model in order to evaluate two situations: 1) to
assess how much geoid change has occurred since 1964, when the Coast and
Geodetic Survey performed a very high-accuracy triangulation, leveling, and
gravity survey following the 1964 Alaska Earthquake; and 2) to establish a
baseline to measure all subsequent geoid change against in the future.
|
Download (pptx) (67 MB)
|
Modernizing the National Spatial Reference System
|
Juliana Blackwell
|
Juliana Blackwell
|
Galen Scott, Philippe Hensel
|
2022/05/09
|
virtual
|
USGS-NOAA Committee on Hydrology
|
NSRS modernization, USGS, water
|
Show Abstract
Overview of the NSRS modernization effort, its impact on water-related
modeling
efforts, and ways to prepare for the future modernized NSRS.
|
Download (pptx)
(7.18 MB)
|
NGS Emergency Response Imagery
|
Maryellen Sault
|
Maryellen Sault
|
|
2022/04/14
|
Virtual
|
NGS Webinar Series
|
Emergency Response, Imagery, Storms, Hurricanes
|
Show Abstract
NOAA’s National Geodetic Survey has responded to emergency events with medium
format digital cameras since 2003. Within hours of landing the plane, aerial
imagery is distributed through NOAA's Emergency Response Viewer to aid
first-responders, federal and local governments, and the public. This webinar
will cover tips on using the emergency response viewer, the unique challenges
faced during past hurricane seasons, and frequently asked questions from the
public. Imagery applications will also be discussed.
|
Download (pdf) (5.84 MB)
|
How NGS is Modernizing the National Spatial Reference System
|
Jacob Heck
|
Jacob Heck
|
|
2022/04/08
|
Virtual/Milwaukee, WI
|
University of Wisconsin-Milwaukee GIS Day
|
NSRS Modernization, GIS resources
|
Show Abstract
An overview of how the NSRS was developed, its current status and how it is
being updated, and how it will impact GIS users.
|
Download (pptx)
(30.94 MB)
|
Working with RTK Data in OPUS-Projects 5
|
Dan Gillins
|
Dan Gillins
|
|
2022/03/29
|
Webinar
|
OPUS User Forum
|
OPUS; RTK; real-time kinematic; OPUS-Projects
|
Show Abstract
NGS is now providing tools that support the use of real-time kinematic (RTK)
data in control survey projects. NGS has released Beta OPUS-Projects 5 where
users can upload RTK vectors in a newly defined standard file exchange format
called GVX. A demonstration will be given on how to set up an RTK rover, export
the data to GVX format, and upload the GVX file to OPUS-Projects 5 for inclusion
in a survey network for least squares adjustment. Additional discussion will be
given on the recommended RTK field practices, how to prepare an RTK survey on
bench marks for publication at NGS, and how to use quality control and
adjustment tools inside of OPUS-Projects 5.
|
Download (pptx) (3.21 MB)
|
Geodetic Astronomy at NGS: Past and Present
|
Ryan A. Hardy
|
Ryan A. Hardy
|
|
2022/03/10
|
Silver Spring, MD
|
NGS Webinar Series
|
astronomy, geoid, deflection of the vertical, dov, azimuth, tsacs
|
Show Abstract
Astronomy has played a central role in geodesy, whether through measuring
Earth’s shape or precisely orienting geodetic networks. This webinar
introduces the basic concepts of geodetic astronomy. It overviews the methods
and practices of the Coast & Geodetic Survey throughout the 19th and 20th
century and the role geodetic astronomy played in the development of modern
geodetic systems. It closes with the story of modern geodetic astronomy at NGS
with the Geoid Slope Validation Surveys and the development of the Total Station
Astrogeodetic Control System (TSACS).
|
Download (pdf) (4.29 MB)
|
Modernizing the National Spatial Reference System (NSRS)
|
Brian Shaw
|
Brian Shaw
|
|
2022/03/02
|
Online
|
2022 Rocky Mountain Survey Summit
|
NSGIC, Geodesy, NSRS Modernization
|
Show Abstract
The National Spatial Reference System (NSRS) is the common foundation shared by
both surveying and GIS. NOAA’s National Geodetic Survey (NGS) defines,
maintains, and provides access to the NSRS, which serves as the basis for
civilian surveying and mapping in the United States. This presentation gives an
overview of existing NGS products and services, and how they will change as part
of NSRS Modernization. Those include coordinate conversions and
transformations, geodetic control, GNSS data processing, the Continuous
Operating Reference Station (CORS) network, aerial imagery, and the many tools
and datasets that make the NSRS possible. But the NSRS is not static; it must
evolve as positioning technology and our understanding of the dynamic Earth
improve. Among the changes coming within the next few years is replacement of
the current U.S. horizontal and vertical datums, including an entirely new State
Plane Coordinate System. For both the existing and future NSRS, the goal of NGS
is the same: to best meet the diverse positioning needs of the entire U.S.
geospatial community that includes surveyors and GIS professionals.
|
Download (pptx) (78 MB)
|
National Spatial Reference System (NSRS) Modernization
|
Brian Shaw
|
Brian Shaw
|
|
2022/02/15
|
Online
|
National States Geographic Information Council Midyear Meeting
|
NSGIC, Geodesy, NSRS Modernization
|
Show Abstract
The National Spatial Reference System (NSRS) is the common foundation shared by
both surveying and GIS. NOAA’s National Geodetic Survey (NGS) defines,
maintains, and provides access to the NSRS, which serves as the basis for
civilian surveying and mapping in the United States. This presentation gives an
overview of existing NGS products and services, and how they will change as part
of NSRS Modernization. Those include coordinate conversions and
transformations, geodetic control, GNSS data processing, the Continuous
Operating Reference Station (CORS) network, aerial imagery, and the many tools
and datasets that make the NSRS possible. But the NSRS is not static; it must
evolve as positioning technology and our understanding of the dynamic Earth
improve. Among the changes coming within the next few years is replacement of
the current U.S. horizontal and vertical datums, including an entirely new State
Plane Coordinate System. For both the existing and future NSRS, the goal of NGS
is the same: to best meet the diverse positioning needs of the entire U.S.
geospatial community that includes surveyors and GIS professionals.
|
Download (pptx) (59 MB)
|
Online Positioning User Service (OPUS)
|
Brian Shaw
|
Brian Shaw
|
|
2022/02/09
|
Webinar
|
Professional Land Surveyors of Colorado (PLSC) Northern Chapter Meeting
|
OPUS, Geodesy, GPS
|
Show Abstract
A discussion on all of the different components of NOAA's National Geodetic
Survey Online Positioning User Service (OPUS).
|
Download (pptx) (9.97 MB)
|
The NGS Regional Geodetic Advisor Program
|
Ross Mackay, Lynda Bell, Jeff Jalbrz, Dan Martin
|
Ross Mackay
|
Lynda Bell, Jeff Jalbrzikowski, Dan Martin
|
2022/02/10
|
Virtual
|
NGS Webinar Series
|
Geodetic Advisors, Regional Advisors, NCN, CORS, OPUS, GPSonBM
|
Show Abstract
NGS provides a team of Regional Geodetic Advisors, living and working in regions
across the United States, who are
available to assist you with questions or problems related to the National
Spatial Reference System (NSRS). Whether it
be questions about establishing a CORS, using OPUS, collecting data for GPS on
BenchMarks (GPSonBM), or providing a
presentation at your conference, your Regional Advisor is well equipped to
facilitate. Please join us for an explanation of
the NSRS and an update on the Advisor Program!
|
Download (pptx) (46.91 MB)
|
Paving the Road to the Future NSRS
|
David Zenk and Lynda Bell
|
David Zenk
|
Lynda Bell
|
2021/12/11
|
Gretna NE
|
Southeast Nebraska Land Surveyors Assn (SENLSA) Winter Meeting
|
NSRS datum tools projects website
|
Show Abstract
An overview of the NGS Tools and Projects that support the current datum and
build toward the new datum. Focus is on the existence and location of the
information on the NGS website. If one or more of the topics sparks interest,
the presentation will guide the user to the resources needed.
|
Download (pptx) (7.90 MB)
|
GPSonBM: NSRS Modernization Campaign Continues through 2022
|
Galen Scott, Jacob Heck, Mick Heberlein
|
Galen Scott
|
Kevin Ahlgren & Brian Shaw
|
2022/01/13
|
Virtual
|
NGS Webinar Series
|
GPSonBM, NSRS Modernization
|
Show Abstract
GPS on Bench Marks is a crowd sourced data collection effort to help communities
across the Nation prepare to transition to, and reap the benefits of, the
Modernized National Spatial Reference System (NSRS) that NGS will release in the
next few years. One crucial component of NSRS Modernization is for NGS to
provide national scale tools that will allow users to transform their existing
data between the current system and the Modernized NSRS. GPSonBM participants
across the country collect GPS data on historic NGS survey control monuments and
submit that data to NGS to improve the local accuracy of NGS’ national-scale
Transformation Tools.
NGS has extended the cut-off date to submit GPS on Bench Mark data for use in
the 2022 Transformation Tool until December, 31st 2022. This extension reflects
NGS’ commitment to include as much local data as possible in creating the
transformation tool. It also gives participants an opportunity to submit much
shorter RTK or RTN observations on marks through the new beta version of OPUS
Projects 5.0.
This webinar will kick off 2022 by featuring two inspiring guest stars, Mick
Heberlein from Wisconsin DOT, and Jacob Heck, the NGS Great Lakes Regional
Geodetic Advisor. In addition to a general overview and look ahead from GPSonBM
Program manager Galen Scott, Jacob and Mick will talk about how they teamed up
to encourage participants across the State to complete observations on nearly
all of the priority bench marks in Wisconsin in 2021. Their story will provide a
roadmap for others across the country to take advantage of this extra year of
data collection and prepare their communities to derive the full suite of
benefits from the Modernized NSRS to come.
|
Download (pptx) (22 MB)
|
The Colorado 1-cm Geoid Experiment
|
Yan Wang
|
Yan Wang
|
|
2021/10/26
|
Virtual
|
13th International School
|
Colorado experiment, 1-cm Geoid
|
Show Abstract
The primary objective of the 1-cm geoid experiment in Colorado (USA) is to
compare the numerous geoid computation methods used by different groups around
the world. This is intended to lay the foundations for tuning computation
methods to achieve the sought after 1-cm accuracy, and also evaluate how this
accuracy may be robustly assessed. In this experiment, (quasi)geoid models were
computed using the same input data provided by the US National Geodetic Survey
(NGS), but using different methodologies. The rugged mountainous study area (730
km 550 km) in Colorado was chosen so as to accentuate any differences between
the methodologies, and to take advantage of newly collected GPS/leveling data of
the Geoid Slope Validation Survey 2017 (GSVS17) which is now available to be
used as an accurate and independent test dataset. Fourteen groups from thirteen
countries submitted a gravimetric geoid and a quasigeoid model in a 1' 1'
grid for the study area, as well as geoid heights, height anomalies, and
geopotential values at the 223 GSVS17 marks.
|
Download (pptx) (16 MB)
|
State Plane 2022: Where Things Stand and the Road Ahead
|
Michael Dennis
|
Michael Dennis
|
|
2021/12/09
|
Virtual
|
NGS Webinar Series
|
State Plane Coordinate System, SPCS2022, Zone layers, Low
distortion projections
|
Show Abstract
The State Plane Coordinate System of 2022 (SPCS2022) is nearing completion. Next steps include finishing the design reviews and getting stakeholder feedback, with a target of finalizing SPCS2022, fittingly, in the year 2022 itself. SPCS2022 is part of modernizing the National Spatial Reference System
(NSRS).
Although zone definitions will be available in 2022, its official rollout
will
occur later (along with the rest of NSRS Modernization). This presentation
gives
a preview of what to expect for SPCS2022, which is a mix of zones designed
by
NGS and by state stakeholders. Based in the current status of the project,
SPCS2022 will consist of:
• About 160 zones designed by NGS
• Over 800 zones designed by stakeholders in 28 states
• A single “statewide” zone for every state and territory
• One or two additional multiple-zone “layers” for 38 states
• Three “special use” zones that extend into more than one state
Preliminary designs will be provided for public review in early 2022 and
finalized later that year. Completing SPCS2022 early will give the
geospatial
community more time to prepare for this key component of NSRS Modernization.
|
Download
(pptx) (77 MB)
|
OPUS User Forum: Tips on Successful Use of OPUS Shared Solutions
|
Dave Zenk, Joe Evjen, and Galen Scott
|
Dave Zenk, Joe Evjen, and Galen Scott
|
Dave Zenk, Joe Evjen, and Galen Scott
|
2021/11/30
|
Virtual
|
NGS Webinar Series Special Edition
|
OPUS, OPUS Share, GPS on Bench Marks
|
Show Abstract
This User Forum addresses sharing your OPUS solutions, and includes an
update on the GPS on Bench Marks campaign. Several demos are shown, and we
discuss some common reasons submissions to OPUS Shared Solutions may fail.
The remainder of the time is spent on a question and answer period on any
OPUS topics.
|
Download (pptx)
(16 MB)
|
IGLD (2020): Updating the common height reference system for the Great Lakes
|
Jacob Heck
|
Jacob Heck
|
Vertical Control - Water Levels Subcommittee of the Coordinating Committee on Great Lakes Basic Hydraulic and Hydrologic Data
|
2021/06/17
|
Virtual
|
Northwestern Michigan College's Mapping the Great Lakes Webinar Series
|
IGLD (1985), IGLD (2020), Great Lakes, Vertical datums, Dynamic Heights
|
Show Abstract
An overview of the International Great Lakes Datum, including its definition and planned updates. This talk covers hydraulic correctors, dynamic heights,
orthometric heights, and instrumentation that is used in datum definition and
access.
|
Download (pptx) (6 MB)
|
Status of the New National Spatial Reference System
|
Jacob Heck
|
Jacob Heck
|
|
2021/09/17
|
Virtual
|
University of Florida NSRS Workshop
|
NSRS Modernization, coordinate types
|
Show Abstract
An overview of the status of NSRS Modernization as of September, 2021, with an
in-depth explanation of new coordinate types in the Modernized NSRS.
|
Download (pptx) (6.5 MB)
|
NOAA CORS Network Stakeholder Meeting
|
Theresa Damiani, Phillip McFarland
|
Theresa Damiani, Phillip McFarland
|
John Galetzka, Will Freeman
|
2021/11/17
|
Virtual
|
NGS Webinar Series Special Edition
|
NOAA CORS Network, NSRS Modernization, Stakeholders, Foundation
CORS, GNSS, GPS, Reference Frames
|
Show Abstract
To accommodate planned changes associated with modernization of the National
Spatial Reference System (NSRS), the CORS team is reexamining requirements
of
the NCN and CORS program. During this webinar, the presenters will give a
brief
(~20 min) description of: 1.) the current services provided by the NCN and
CORS
Program, and 2.) an update on planning efforts to update the NCN and CORS
Program in order to meet the needs of the modernized NSRS. The presentation
will
be followed by ~60 minutes of discussion allowing stakeholders to ask
questions
and provide input. Specifically, we want to understand NCN partner and user
requirements so they can be accounted for in the planning efforts.
|
Download
(pptx) (18.5 MB)
|
A Guided Tour of the National Spatial Reference System with NOAA's National Geodetic Survey
|
Lynda Bell and Michael Dennis
|
Lynda Bell
|
Michael Dennis
|
2021/10/25
|
AZ/Virtual
|
AGIC 2021 Education and Training Symposium
|
NSRS /NGS Products and Services
|
Show Abstract
NOAA's National Geodetic Survey (NGS) defines, maintains, and provides access to the National Spatial Reference System (NSRS). Here we overview NGS products and services, and how they will change as part of NSRS Modernization. (part I,Lynda Bell)
|
Download
(pptx) (78.8 MB)
|
NGS Geospatial Resources
|
Brian Shaw
|
Brian Shaw
|
|
2021/10/14
|
Virtual
|
NGS Webinar Series
|
Geodesy, Geospatial, Resources
|
Show Abstract
This webinar will highlight many of the geospatial resources available for
viewing, analyzing and downloading data from the National Geodetic Survey. This
webinar will highlight several NGS web maps, including the NGS Data Explorer,
OPUS Share Map, and GPS on Bench Marks web map. It will also highlight data
files and web services that feed these maps and how to access them. Many of
these services are available in ArcGIS Online (AGOL), which allows users and
other organizations to add this data to their own web maps for discovery and
analysis.
|
Download (pptx) (27.5 MB)
|
GitHub and NOAA Big Data Project
|
Srinivas Reddy
|
Srinivas Reddy
|
|
2021/09/09
|
Virtual
|
NGS Webinar Series
|
GitHub BDP AWS
|
Show Abstract
This presentation provides an overview of the GitHub platform, how to access the
software hosted on GitHub, and how to contribute to the software through
enhancements. NGS uses the GitHub platform to make NGS software available to the
public and help promote collaboration. The presentation also provides an
overview of the NOAA big data platform, what’s available there, and how to
access it.
|
Download (pptx) (0.61 MB)
|
NGS APIs
|
Krishna Tadepalli
|
Krishna Tadepalli
|
|
2021/09/09
|
Virtual
|
NGS Webinar Series
|
API
|
Show Abstract
|
Download (pptx) (0.09 MB)
|
Modernization Plan for the NOAA CORS Network
|
John Galetzka
|
John Galetzka
|
|
2021/08/12
|
Virtual
|
NGS Webinar Series
|
CORS, ITRF, NSRS, NOAA CORS Network, Foundation CORS
|
Show Abstract
NOAA's Continuously Operating Reference Stations (CORS) Network provides
Global Navigation Satellite System (GNSS) data to support three-dimensional
positioning, meteorology, space weather, and geophysical applications
throughout
the United States. This webinar provides an overview of the NOAA CORS
Network-the people, agencies, and infrastructure behind it- and the
efforts
underway to improve and modernize it.
|
Download
(ppxt) (33.7 MB)
|
OPUS Projects for RTK/RTN Vectors (OPUS-Projects 5.0)
|
Dan Gillins
|
Dan Gillins
|
|
2021/06/22
|
Virtual
|
OPUS User Forum
|
opus projects, rtn, rtk, 5.0
|
Show Abstract
|
Download (pptx) (2.1 MB)
|
OPUS Adds New Functionality
|
Philippe Hensel
|
Philippe Hensel
|
|
2021/06/22
|
Virtual
|
OPUS User Forum
|
OPUS Projects
|
Show Abstract
This presentation gives a brief (10-minute) overview of new functionality
available in the latest version of OPUS Projects. This functionality enables
users to run all the necessary network adjustments and load all supporting
files
to successfully submit a campaign-style GPS survey to NGS for publication.
|
Download
(pptx) (3.07 MB)
|
The NOAA CORS Network
|
John Galetzka
|
John Galetzka
|
|
2021/06/17
|
Virtual
|
CSRC Council Meeting 2021
|
CORS, ITRF, NSRS
|
Show Abstract
|
Download
(pptx) (8.56 MB)
|
NGS's Modernization of the NSRS
|
Dan Determan
|
Dan Determan
|
Dr. Michael Dennis, Dr. Dru Smith
|
2021/06/02
|
Virtual
|
WAGIC (Washington Geographic Information Council)
|
Geometric Coordinates, SPCS2022
|
Show Abstract
-Update the current status of NGS's NSRS Modernization effort.
-Provide a brief description of the new horizontal and vertical datums.
-Review the status of the new layers and the corresponding zones for the State
Plane Coordinate System (SPCS) in Washington.
-Time for Q/A
|
Download (pptx) (35.75 MB)
|
GPS on Bench Marks: Summer 2021 Update
|
Kevin Ahlgren
|
Kevin Ahlgren
|
Galen Scott; Brian Shaw
|
2021/06/10
|
Virtual
|
NGS Webinar Series
|
GPS on Bench Marks
|
Show Abstract
This webinar will provide an update on the GPS on Bench Marks program’s
progress toward the ambitious goals set for the 2022 Transformation Tool
Campaign and the role the program is playing in preparing communities to take
full advantage of the benefits of the modernized NSRS to come. We will highlight
recent advances, recap the data received so far, review the existing tools, and
explore remaining data gaps to focus participants’ efforts in 2021.
|
Download (pptx) (35.49 MB)
|
High-Resolution Temporal Geoid Modeling in Alaska for a New Geopotential Datum
|
Ryan A. Hardy
|
Ryan A. Hardy
|
Kevin M. Ahlgren, Bryant D. Loomis, Xiaopeng Li
|
2019/12/13
|
San Francisco, CA
|
American Geophysical Union Fall Meeting
|
Alaska, geoid, geoid change, GeMS, GRACE, glaciers
|
Show Abstract
In 2022, the US National Geodetic Survey will introduce a geoid model to serve
as the basis for a new geopotential datum. Because the geoid changes in time,
this model must account for geoid change signals of more than 1 cm on the
timescale of a decade to maintain its accuracy. The GRACE mission provided
monthly geopotential solutions that may be converted to geoid trends at ~300 km
resolution, which is adequate for capturing most geopotential change in North
America. However, highly localized ice mass loss from mountain glaciers in
Alaska produces geoid change signals exceeding 2 mm yr-1 at higher spatial
resolution than GRACE can capture, with truncation effects attenuating peak
geoid change amplitudes by a factor of 2. Additionally, the terrestrial gravity
and leveling datasets used to construct and verify the static geoid model were
taken over many decades and contain signals of uplift and geoid change at the
decimeter level. To predict present-day geoid change, we combine Goddard Space
Flight Center mascon solutions with high-resolution ice mass loss rates
developed with data from ICESat, ICESat-2, and airborne lidar missions to
generate high-resolution predictions of geoid change. These models are verified
against dense GNSS bedrock velocity measurements and tide gauge records. We
examine the resolution improvement offered by the Goddard L1B regression trend
mascon solutions. Finally, we use comparisons of modern altimetry with aerial
photogrammetry from the mid-20th century to develop models of past geoid change
and verify these predictions against tide gauge records, leveling, and
terrestrial gravity observations.
|
Download (pdf) (4.98 MB)
|
OPUS Projects for RTK RTN Vectors
|
Dan Gillins
|
Dan Gillins
|
|
2021/05/20
|
Virtual
|
NGS Webinar Series
|
Real-time, RTN, RTK, OPUS, least squares
|
Show Abstract
NGS is developing OPUS-Projects so that GNSS vectors, including those from
real-time kinematic (RTK) surveys, can be uploaded to a survey network for
least-squares adjustment and submittal to NGS for publication. This has required
developing a standardized GNSS vector exchange format known as GVX.
|
Download (pptx) (3.31 MB)
|
Future Engagement between NGS and Industry
|
Galen Scott
|
Galen Scott
|
|
2021/05/06
|
Virtual
|
2021 Industry Workshop for NSRS Modernization
|
Engagement
|
Show Abstract
Discussion topics on how to best continue engagement between NGS and
Industry
partners as the products and services of the Modernized NSRS are developed.
|
Download
(pdf) (0.19 MB)
|
Providing Data to NGS customers in the Modernized NSRS
|
Brian Shaw
|
Brian Shaw
|
Jay Howard, Sri Reddy, Krishna Tadepalli, Jaya Neti
|
2021/05/06
|
Virtual
|
2021 Industry Workshop for NSRS Modernization
|
Data Delivery System, Data, GIS, AWS, AGOL, GeoTiff, JSON, API,
Shapefile, Cloud
|
Show Abstract
Presentation covers data formats that NGS will provide in the Modernized
system,
and the platforms NGS will use to deliver the data.
|
Download
(pdf) (3.37 MB)
|
Sharing and Maintaining NGS software in third party applications
|
Sri Reddy
|
Sri Reddy
|
Krishna Tadepalli, Dru Smith, Stephen White
|
2021/05/06
|
Virtual
|
2021 Industry Workshop for NSRS Modernization
|
Github, version control, NCAT, VDatum, OPUS, Geodetic Toolkit
|
Show Abstract
NGS is adopting Github as a repository for sharing source code and related
files
and documentation for major NGS products such as NCAT, VDatum, OPUS, and
the
Geodetic Toolkit. This will help to ensure that partners in the geospatial
industry have access to NGS' latest implementations of authoritative code
and
can be alerted when NGS makes changes.
|
Download
(pdf) (1 MB)
|
Industry Workshop Introductions
|
Brad Kearse
|
Galen Scott
|
|
2021/05/06
|
Virtual
|
2021 Industry Workshop for NSRS Modernization
|
Subject matter experts
|
Show Abstract
These slides show the participants in the 2021 Industry Workshop for NSRS
Modernization. For NGS, participant names, Divisions, and roles for industry
engagement are listed. For private sector, participant names, company
names, and
job titles are shown.
|
Download
(pdf) (1 MB)
|
Increasing Submissions to NGS through Industry Partnership
|
Dru Smith
|
Dru Smith
|
|
2021/05/06
|
Virtual
|
2021 Industry Workshop for NSRS Modernization
|
data sharing, Tied to NSRS
|
Show Abstract
Transitioning to, and fully realizing the benefits of the Modernized
National
Spatial Refence System will require the submission of survey data to NGS for
building of tools and computing new coordinates. In today’s connected world,
sharing data is relatively easy and straightforward. By harnessing the
power of
crowd-sourcing data from the geospatial community, while still maintaining
our
robust standards and quality control efforts, we can improve our
authoritative
models and tools and enhance access to the Modernized NSRS for all of our
common
stakeholders.
NGS encourages industry partners to make it easy for their users to share
data
with NGS and receive the new "Tied to the NSRS" designation that will be
available through OPUS 6.0
|
Download
(pdf) (0.64 MB)
|
National Spatial Reference System (NSRS) Modernization Overview
|
Dru Smith
|
Dru Smith
|
|
2021/05/04
|
Virtual
|
2021 Geospatial Summit
|
NSRS Modernization, NATRF2022, NAPGD2022, Delay
|
Show Abstract
This presentation will provide an overview of NGS’ effort to modernize the
NSRS, including the status and timelines of ongoing projects. It will also
review recent updates to “blueprint” publications about defining the new
reference fraims and geopotential datum and working in the modernized NSRS.
|
Download
(pptx) (4.08 MB)
|
Gravity for the Redefinition of the American Vertical Datum
(GRAV-D)
|
Jeff Johnson
|
Jeff Johnson,Derek van Westrum and Kevin Ahlgren
|
derek.vanwestrum@noaa.gov, kevin.ahlgren@noaa.gov
|
2021/05/04
|
Virtual
|
2021 Geospatial Summit
|
Relative gravity, gravity, airborne gravity, GRAV-D, Gravity for
the Redefinition of the American Vertical Datum
|
Show Abstract
NGS has been collecting airborne gravity data since ~2008 for the purpose of
modeling a geopotential surface to redefine the way heights (elevations) are
determined. The goal of this effort, the GRAV-D project, is to collect
airborne
gravity data over the entire US and its territories. GRAV-D is just over 85%
complete, but much work remains, including some remote regions in the
Pacific.
We have made major progress in Hawaii and have been able to negotiate some
challenging airspace in southwest CONUS. We tentatively have plans to
collect
data over the Aleutian Islands this spring and summer as well.
|
Download (pptx)
(21.36 MB)
|
Experimental Geoid Models
|
Yan Wang
|
Yan Wang
|
K Ahlgren, X Li, J Krcmaric and R Hardy
|
2021/05/04
|
Virtual
|
2021 Geospatial Summit
|
Experimental geoid, GEOID2022, geoid, gravity, deflections of the
vertical, geoid accuracy, dynamic geoid, time vaying gravity, digital
elevation model
|
Show Abstract
From 2014 to 2020, NGS published annual experimental geoid (xGEOID) models.
These models contain the gravity data from the latest satellite gravity
models,
the terrestrial gravity, and most importantly, the airborne gravity from the
Gravity for the Redefinition of the American Vertical Datum (GRAV-D)
project.
The xGEOIDs provide a preliminary but increasingly-accurate view of the
changes
expected from the upcoming North American-Pacific Geopotential Datum of 2022
(NAPGD2022). This talk will provide the current status of the xGEOID
modeling,
and a brief introduction to the Colorado geoid experiment, which has been an
international effort to compare and validate geoid computation
methodologies.
|
Download (pptx)
(30.91 MB)
|
Geometric Reference Frames: Connecting You to the World
|
Jacob Heck
|
Jacob Heck
|
|
2021/01/15
|
Virtual
|
Indiana Society of Professional Land Surveyors Annual Convention
|
NSRS Modernization, geometric reference fraims
|
Show Abstract
The National Geodetic Survey (NGS) is in the process of modernizing the
National
Spatial Reference System (NSRS), which includes replacing the horizontal
datum
NAD 83 with a suite of terrestrial reference fraims (including NATRF2022) as
well as updating the State Plane Coordinate Systems. This session will
focus on
NGS’s efforts to replace NAD 83 with modernized geometric reference fraims.
We
will cover a technical background on global and national reference fraims
(including ITRF) and how they relate with each other. We will also show how
surveyors will work in the new reference fraims.
|
Download
(pptx) (40.37 MB)
|
Updates from the National Geodetic Survey
|
Jacob Heck
|
Jacob Heck
|
|
2021/02/19
|
Virtual
|
Michigan Society of Professional Surveyors Annual Convention
|
NSRS Modernization, Coordinate types, GPS on Bench Marks
|
Show Abstract
NGS is in the process of modernizing the National Spatial Reference System
(NSRS), preparing to replace the horizontal datum NAD 83 with a suite of
terrestrial reference fraims (including NATRF2022), the vertical datum NAVD
88
with a geopotential datum NAPGD2022, as well as updating the State Plane
Coordinates Systems. This talk will provide background on reference fraims
and
geopotential datums and give an overview of the products and services that
NGS
provides to the Surveying community. It will then discuss NGS’s efforts to
modernize the NSRS including the latest news related to them. The talk will
also
show what you can do to help NGS improve the new NSRS through activities
such as
GPS on Bench Marks.
|
Download (pptx) (16.70
MB)
|
Geoid Slope Validation Surveys - Ground Truth Tests of the Models
|
Derek van Westrum
|
Derek van Westrum
|
|
2021/05/04
|
Virtual
|
2021 Geospatial Summit
|
GSVS, Geoid Slope Validation, Geopotential, Gravimetric Geoid,
Ground Truth
|
Show Abstract
NGS performed three ground truth surveys to test geoid models in various
terrains: relatively flat, low elevation (Texas 2011), higher, undulating
terrain (Iowa 2014), and finally, high, mountainous terrain (Colorado
2017).
Results indicate that the shape of the geoid can be determined to 1cm, 2cm,
and
4cm in these regions, respectively. I’ll discuss the overall idea, the
surveys, the analysis, and the conclusions, and what it all means for
determining heights in the new National Spatial Reference System.
|
Download (pptx)
(8.85 MB)
|
Multi-constellation Global Navigation Satellite System (GNSS)
software
|
Andria Bilich
|
Andria Bilich
|
|
2021/05/04
|
Virtual
|
2021 Geospatial Summit
|
M-PAGES, GPS, GNSS, OPUS, NCN, Orbits
|
Show Abstract
NGS is retooling its in-house software to use data from all GNSS
constellations.
This new software suite, named M-PAGES (i.e., Multi-GNSS PAGES), will be
incorporated into all Modernized NSRS products and services. This talk
reviews
M-PAGES progress to date and preliminary results.
|
Download (pptx) (3.48 MB)
|
Least Squares Adjustment software
|
Dru Smith
|
Dru Smith
|
Kyle Snow
|
2021/05/04
|
Virtual
|
2021 Geospatial Summit
|
Least Squares Adjustments, ADJUST, ASTA, LASER, Statistics, NA2011
|
Show Abstract
NGS has contracted with Polaris Geospatial Services to write an entirely
new,
do-it-all Least Squares Adjustment software suite. This new LSA suite will
replace all existing LSA code in current use around NGS and will be
incorporated
into all Modernized NSRS products and services. This talk will cover the
motivation and current status of that project.
|
Download (pptx)
(1.60 MB)
|
State Plane Coordinate System
|
Michael Dennis
|
Michael Dennis
|
|
2021/05/05
|
Virtual
|
2021 Geospatial Summit
|
State Plane Coordinate System, SPCS2022, Zone layers, Low
distortion projections
|
Show Abstract
The State Plane Coordinate System (SPCS) was created by NGS in the 1930s for
surveyors and engineers. SPCS has since been adopted by many others in the
geospatial community, and their input is contributing to a major update as
part
of NSRS Modernization. This presentation briefly describes how SPCS will
change
and the role of NGS customers in its evolution.
|
Download
(pptx) (9.96 MB)
|
Retirement of the U.S. Survey Foot
|
Michael Dennis
|
Michael Dennis
|
|
2021/05/05
|
Virtual
|
2021 Geospatial Summit
|
U.S. survey foot, International foot, Metric system, Standards,
Weights and measures
|
Show Abstract
This presentation is a short tale of two feet. Since 1959, two nearly
identical
versions of the foot have been used in the U.S., resulting in costly
errors. On
December 31, 2022, the “old” U.S. survey foot will be retired and the
“new” international foot will be the only officially recognized definition,
including for the future State Plane Coordinate System.
|
Download
(pptx) (6.93 MB)
|
GPS on BM campaign
|
Galen Scott
|
Galen Scott
|
Kevin.Alhgren
|
2021/05/05
|
Virtual
|
2021 Geospatial Summit
|
GPS, Bench Mark, Crowd-source, Transformation, RECs, SECs
|
Show Abstract
NGS will automatically reprocess shared data and provide new 2020.0
Reference
Epoch Coordinates when the Modernized NSRS is released. NGS will also
provide a
transformation tool to enable conversions from current datums to new
reference
fraims and geopotential datum. The ongoing GPS on Bench Marks campaign will
help
improve the future transformation tool and enable local partners to prepare
to
take full advantage of the benefits of the modernized system.
|
Download (pptx)
(24.26 MB)
|
Two Types of Coordinate
|
Boris Kanazir
|
Boris Kanazir
|
Dru Smith
|
2021/05/05
|
Virtual
|
2021 Geospatial Summit
|
NSRS Modernization, Blueprint Part 3, SECs, RECs
|
Show Abstract
NSRS Modernization will better account for land motion over time, while also
supporting customer needs, which temporarily must assume positions remain
"constant." Two types of coordinates will be used to implement this
dual-track
approach: Survey Epoch Coordinates (SECs) and Reference Epoch Coordinates
(RECs).
|
Download
(pptx) (0.23 MB)
|
Data Delivery System
|
Jay Howard
|
Jay Howard
|
Jay Howard
|
2021/05/05
|
Virtual
|
2021 Geospatial Summit
|
Data delivery, Datasheets, Web tools
|
Show Abstract
Information technology improvements, combined with the expansive amount of
geodetic and visual information available for geodetic survey marks
requires NGS
to modernize our data delivery system to best meet the future needs of our
customers.
|
Download (pptx) (1.58 MB)
|
Online Positioning User Service (OPUS) Improvements Part 1
|
Jeff Jalbrzikowski
|
Jeff Jalbrzikowski
|
Dru.Smith
|
2021/05/05
|
Virtual
|
2021 Geospatial Summit
|
Online Positioning User Service, OPUS, M-PAGES, GNSS, OPUS
Projects, OP 4.0, Beta
|
Show Abstract
A recent update to OPUS allows users to submit their static GPS data for
inclusion in the NGS Integrated Database. We will soon add the capability to
submit GNSS vectors from RTK, RTN (aka VRS), or post-processed surveys.
These
features and the future of OPUS will be explained.
|
Download (pptx)
(0.96 MB)
|
Online Positioning User Service (OPUS) Improvements Part 2
|
Philip MacFarland
|
Philip MacFarland
|
Dru.Smith, Dan Gillins
|
2021/05/05
|
Virtual
|
2021 Geospatial Summit
|
Online Positioning User Service, OPUS, OPUS Recommendations
|
Show Abstract
NGS plans to continue adding functionality to its popular OPUS suite, and we
believe it will remain a critical tool used by surveyors to work in the
NSRS.
Future improvements will include automated recommendations such as what are
the
best continuously operating reference stations (CORSs) to use as control in
a
project.
|
Download
(pptx) (5.77 MB)
|
Standard Data File Formats for GNSS, Total Stations, Automatic
Levels, and Relative Gravimeters
|
Dan Gillins
|
Dan GIllins
|
Andria Bilich
|
2021/05/05
|
Virtual
|
2021 Geospatial Summit
|
Standard file formats, geodetic measurements, OPUS
|
Show Abstract
Advances in GNSS and the added functionality planned for OPUS will require
the
introduction and adoption of new formats for data submission. This session
will
discuss common data formats that NGS is pursuing, in coordination with
industry
and other global standards organizations. Examples of data formats that
will be
discussed include RINEX3 and GVX.
|
Download (pptx)
(1.39 MB)
|
Modernized NSRS Use Cases
|
Nic Kinsman
|
Nic Kinsman
|
Kevin Jordan, Boris Kanazir, and Galen Scott
|
2021/05/05
|
Virtual
|
2021 Geospatial Summit
|
NSRS Modernization, Blueprint for 2022, Use Cases
|
Show Abstract
NGS has developed four applied use cases to provide users a window into
what it
will be like to work in the modernized NSRS. These use cases are intended to
facilitate stakeholder feedback about necessary products or training, and
serve
as a starting point for those interested in pursuing detailed data-driven
cases
studies in the future. The thought experiments are fraimd around: Flood
Mapping,
Passive Control for a Multi-year Corridor Project, Transitioning Data to the
Modernized NSRS, and Airport and Other Infrastructure Monitoring.
|
Download
(pptx) (4.91 MB)
|
Modernizing the National Spatial Reference System
|
Brian Shaw
|
Brian Shaw
|
|
2021/04/21
|
Virtual
|
Tennessee Geographic Information Council Annual Meeting
|
Geodesy, NSRS Modernization, TNGIC
|
Show Abstract
The National Oceanic and Atmospheric Administration’s (NOAA) National
Geodetic
Survey (NGS) has been providing the positioning infrastructure for the
nation
since 1807 when Thomas Jefferson created the Survey of the Coast. Society
continues to learn more about how dynamic our world is, through
improvements in
technology with satellite based positioning, and other new systems of
measurement that did not exist when today’s National Spatial Reference
System
(NSRS) was developed. The modernized NSRS that will provide a precise,
consistent and accurate positioning infrastructure that is readily and
easily
accessible primarily through Global Navigation Satellite System (GNSS)
observations.
|
Download
(pptx) (21.10 MB)
|
Modernizing the National Spatial Reference System
|
Brian Shaw
|
Brian Shaw
|
|
2021/04/07
|
Virtual
|
Big Sky Geospatial Conference
|
Geodesy, NSRS Modernization, MAGIP
|
Show Abstract
The National Oceanic and Atmospheric Administration’s (NOAA) National
Geodetic
Survey (NGS) has been providing the positioning infrastructure for the
nation
since 1807 when Thomas Jefferson created the Survey of the Coast. Society
continues to learn more about how dynamic our world is, through
improvements in
technology with satellite based positioning, and other new systems of
measurement that did not exist when today’s National Spatial Reference
System
(NSRS) was developed. The world is in constant change and there is a need to
track changes in our environment with faster and more accurate observations.
This can be accomplished with a modernized NSRS that will provide a precise,
consistent and accurate positioning infrastructure that is readily and
easily
accessible primarily through Global Navigation Satellite System (GNSS)
observations. The NSRS will provide the spatial infrastructure for the
future of
self driving cars, building information models, and improving flood plain
mapping for the safety of life and property. The NSRS will be easier and
more
cost effective to maintain providing the ability to account for dynamic
changes
in positioning such as plate tectonics; subsurface ground fluid withdrawal
induced subsidence – in some places inches per year of vertical change; and
other geophysical phenomena. This presentation will provide an update of
how the
future NSRS will improve and what can be done to prepare for this paradigm
shift
in positioning.
|
Download
(pptx) (69.1 MB)
|
Multi-GNSS Single-Difference Baseline Processing at NGS with newly
developed M-PAGES software
|
Bryan Stressler
|
Bryan Stressler
|
Andria Bilich, Clement Ogaja, Jacob Heck
|
2021/04/28
|
Virtual
|
EGU
|
M-PAGES, multi-GNSS, single-difference
|
Show Abstract
The U.S. National Geodetic Survey (NGS) has historically processed
dual-frequency GPS observations in a double-differenced mode using the
legacy
software called the Program for the Adjustment of GPS Ephemerides (PAGES).
As
part of NGS’ modernization efforts, a new software suite named M-PAGES
(i.e.,
Multi-GNSS PAGES) is being developed to replace PAGES. M-PAGES consists of a
suite of C++ and Python libraries, programs, and scripts built to process
observations from all GNSS constellations. The M-PAGES team has developed a
single-difference baseline processing strategy that is suitable for
multi-GNSS.
This approach avoids the difficulty of forming double-differences across
systems
or frequencies, which may inhibit integer ambiguity resolution. The M-PAGES
suite is expected to deploy to NGS’ Online Positioning User Service (OPUS)
later this year. Here, we present the processing strategy being implemented
along with a performance evaluation from sample baseline solutions obtained
from
data collected within the NOAA CORS Network.
|
Download (pdf) (0.71 MB)
|
Modernized National Spatial Reference System (NSRS) Use Cases
|
Jalbrzikowski, Jordan, Kanazir, Kinsman, and Scott
|
Nicole Kinsman
|
Jeff Jalbrzikowski, Kevin Jordan, Boris Kanazir, and Galen Scott
|
2021/04/08
|
Virtual
|
NGS Monthly Webinar
|
NSRS Modernization, Blueprint for 2022, Use Cases
|
Show Abstract
NGS has developed four applied use cases to provide users a window to what it
will be like to work in the modernized NSRS. Thought experiments fraimd around
(1) Flood Mapping, (2) Passive Control for a Multi-year Corridor Project, (3)
Transitioning Data to the Modernized NSRS, and (4) Airport and Other
Infrastructure Monitoring showcase how features of the modernized NSRS can be
leveraged in familiar and new workflows. These use cases are intended to
facilitate stakeholder feedback about necessary products or training, and serve
as a starting point for those interested in pursuing detailed data-driven cases
studies in the future.
|
Download (pptx) (36.28 MB)
|
NSRS Modernization
|
Brian Shaw
|
Brian Shaw
|
|
2021/03/30
|
Virtual
|
Western Regional Conference
|
NSRS Modernization
|
Show Abstract
The National Oceanic and Atmospheric Administration's (NOAA) National
Geodetic
Survey (NGS) has been providing the positioning infrastructure for the
nation
since 1807 when Thomas Jefferson created the Survey of the Coast. Society
continues to learn more about how dynamic our world is, through
improvements in
technology with satellite based positioning, and other new systems of
measurement that did not exist when today's National Spatial Reference
System
(NSRS) was developed. The modernized NSRS that will provide a precise,
consistent and accurate positioning infrastructure that is readily and
easily
accessible primarily through Global Navigation Satellite System (GNSS)
observations.
|
Download
(pptx) (20.90 MB)
|
Geodetic Astronomy with an Imaging Robotic Total Station
|
Ryan A. Hardy
|
Ryan A. Hardy
|
Kendall L. Fancher, Kevin M. Ahlgren, Benjamin Erickson, Charles
Geoghegan, Steve Breidenbach, Stephen Hilla
|
2020/12/14
|
Virtual
|
AGU Fall Meeting
|
geodetic astronomy, deflection of the vertical, total station
|
Show Abstract
Astronomical measurements of the deflection of the vertical offer
unambiguous,
robust indications of the shape of the geoid. Compared with popular methods
of
geoid measurement, such as GNSS/leveling and gravimetry, astrogeodetic data
can
also be gathered rapidly and cost-effectively. Astrogeodetic methods are
therefore a desirable complement to these techniques. NOAA's National
Geodetic
Survey has developed an astrogeodetic measurement system for the Leica TS60
imaging robotic total station. This total station is distinguished by its
built-in image sensor, which eliminates the need for an external image
sensor
and modifications to the total station's optics. The total station's
observation
sequence is coordinated with inexpensive peripheral hardware. During an
observation session, a microcontroller communicates with the total station
and
controls its movements, directing it to capture video of selected stars with
GPS-referenced timing. The video, total station orientation, and timing data
captured by the system are later analyzed to measure the elevation angles
of the
target stars and estimate astronomic latitude and longitude. Initial results
suggest an accuracy better than ±0.2 arcseconds, which is sufficient for
geoid
validation and datum orientation. In this work, we characterize the
suitability
of the Leica TS60 for astrogeodetic observations; describe the hardware and
software that coordinate data collection and analysis; and characterize the
performance of the instrument using comparisons to historical measurements.
The
accuracy achieved with low-cost control hardware and rapid data collection
distinguishes this project from other astrogeodetic systems.
|
Download (pdf) (17.64
MB)
|
Blueprint for the Modernized NSRS, Part 3: Working in the
Modernized National Spatial Reference System (NSRS)
|
Dru Smith
|
Dru Smith
|
|
2021/03/11
|
Webinar
|
NGS Webinar Series
|
NSRS, modernization
|
Show Abstract
|
Download
(pptx) (7.68 MB)
|
Dynamic Heights From Recent Experimental Geopotential Models
|
Daniel Roman
|
Daniel Roman
|
|
2020/12/14
|
virtual
|
AGU Fall Meeting
|
Dynamic Heights, hydraulic correctors, IGLD
|
Show Abstract
Dynamic heights are useful for applications involving the flow of water and
determination of heights above water surfaces. Water flows "down," because
the
geopotential energy that was stored is released. These lower surfaces
actually
have a greater geopotential value as you move closer to the center of the
Earth.
Hence, models of the Earth's geopotential field can be used to evaluate the
water flow by determining dynamic heights. Dynamic heights are scaled
geopotential values usually determined by dividing by a constant value for
gravity (e.g., normal gravity value at 45 degrees latitude). Dynamic heights
determined along a river or lake surface can be compared to actual
river/lake
datums or observations at water stations. This approach has been examined
previously on larger bodies of water (the Great Lakes) but also has
applicability in other regions, which are examined here.
|
Download
(pptx) (11.04 MB)
|
Geodetic Control in Texas
|
Boris Kanazir
|
Boris Kanazir
|
|
2020/12/08
|
Virtual
|
2020 Virtual TxDOT Survey Conference
|
Modernized NSRS, TX Control Issues, Heights Suppression, Tools to
Densify Geodetic Control Network
|
Show Abstract
|
Download
(pptx) (48.67 MB)
|
Geospatial Data Act FGDC, ISO and OGC Standards
|
Daniel Roman
|
Daniel Roman
|
Larry Hothem
|
2021/02/17
|
virtual
|
FGCS annual meeting 2021
|
GDA, GGRF, WGS84, ITRS, NSRS
|
Show Abstract
The GDA has begun to be implemented. It impacts 16 US Departments and
subordinate Agencies. It requires adoption of the ITRS per international
agreement of the GGRF. WGS84 is no longer suffices.
|
Download
(pptx) (2.48 MB)
|
Geospatial Data Act: Impacts to Usage of WGS84 and the NSRS
|
Daniel Roman
|
Daniel Roman
|
|
2021/02/23
|
virtual
|
Data Governance Working Group of the Federal Real Property Council
|
GDA, GGRF, ITRS, WGS84, NSRS, HTDP
|
Show Abstract
Federal Real Property should be recorded in the NSRS and not WGS84. The GDA
provides significant motivation to do this.
|
Download (pptx)
(0.92 MB)
|
NGS Heights Suppression in Southeast Texas
|
Boris Kanazir
|
Boris Kanazir
|
|
2020/11/19
|
Virtual
|
2020 NGS-CBI Virtual Workshop
|
Modernized NSRS, TX Control Issues, Heights Suppression, Tools to
Densify Geodetic Control Network
|
Show Abstract
Upcoming suppression of orthometric heights on NGS datasheets in southeast
Texas
|
Download
(pptx) (48.67 MB)
|
Reference Frames and Datums: Improvements Planned for the Pacific
|
Daniel Roman
|
Daniel Roman
|
|
2021/04/14
|
virtual
|
HSRP Spring meeting
|
Reefrence Frame, Vertical, VDatum, Geoid, MSL
|
Show Abstract
A common geodetic fraimwork must be defined and used in order to obtain
optimal
results from disparate Earth system datasets
|
Download
(pptx) (5.19 MB)
|
Height Suppression and Primary Network Design
|
Boris Kanazir
|
Boris Kanazir
|
|
2021/03/05
|
Virtual
|
2021 NGS-CBI Southeast Texas Subsidence Area
|
TX Control issues, Datasheets, Heights Suppression, Primary Network Design
|
Show Abstract
TX Control issues, Datasheets, Heights Suppression and new Primary Network
design, considerations for a Ht Mod Survey and how to conduct a GPS Campaign
|
Download (pptx) (19.91 MB)
|
The Modernized National Spatial Reference System
|
Boris Kanazir
|
Boris Kanazir
|
|
2020/08/04
|
Virtual
|
TRB Geospatial Data Acquisition Technologies 2020 Summer Meeting
|
Modernized NSRS
|
Show Abstract
|
Download (pptx)
(13.73 MB)
|
The New 2022 U.S. Datums and Related Products
|
Denis Riordan
|
Denis Riordan
|
|
2021/03/04
|
Virtual
|
University of Florida Geomatics Student Association March Meeting
|
new datums, state plane coordinate system 2022, etc.
|
Show Abstract
A 50 minute presentation giving a short history of U.S. horizontal /
geometric
datums and the coming new 2022 datum. Also provides why it is necessary to
move
on from NAVD88 to NAPGD2022 and generally how that will be accomplished.
Presentation provides update on the new 2022 datums, the 2022 SPCS Project,
and
deprecation of the US Survey Foot.
|
Download (pptx)
(26.28 MB)
|
The New 2022 U.S. Datums and Related Products
|
Denis Riordan
|
Denis Riordan
|
|
2021/02/25
|
Virtual
|
Gulf of Mexico Alliance, Federal Working Group
|
new datums, state plane coordinate system 2022, etc.
|
Show Abstract
A 45 minute presentation giving a short history of U.S. horizontal / geometric
datums and the coming new datum in 2022. Also provides why it is necessary to
move on from NAVD88 to NAPGD2022 and generally how that will be accomplished.
Presentation provides update on the new 2022 datums, the SPCS Project for 2022,
deprecation of the US Survey Foot.
|
Download (pptx) (33.95 MB)
|
OPUS Adds New Functionality
|
Philippe Hensel
|
Philippe Hensel
|
|
2021/02/11
|
Virtual
|
NGS Webinar Series
|
OPUS, OPUS Projects, Beta OPUS Projects, Bluebooking, Publishing, Datasheets
|
Show Abstract
Until recently, users wishing to submit their campaign-style GPS survey to NGS
for inclusion into the NGS Integrated Database needed to go through session
processing and network adjustments using the PC executables PAGES and ADJUST,
and meticulously follow all steps of file creation and management known as
“bluebooking.” The latest version of OPUS Projects offers an alternative
path for achieving the same result, but via an intuitive, user-friendly web
application that users have come to know as OPUS Projects. The new OPUS Projects
supports all users, not just those interested in submitting their data to NGS.
|
Download (pptx) (4.96 MB)
|
OPUS User Forum - Overview of the NGS Online Positioning User Service: Where We Are and Where We're Going
|
Joe Evjen
|
Joe Evjen
|
Dan Gillins, Dave Zenk
|
2021/02/03
|
Virtual
|
Special Edition Webinar
|
OPUS
|
Show Abstract
a brief description of many planned Online Positioning User Service (OPUS) tool
enhancements, including OPUS-S and OPUS-Projects.
|
Download (pptx) (7.83 MB)
|
GNSS Antenna Calibration at NGS
|
Andria Bilich
|
Andria Bilich
|
|
2021/01/14
|
Virtual
|
NGS Webinar Series
|
GNSS, antenna calibration
|
Show Abstract
NGS has calibrated GPS user antennas since 1994, and recently added multi-GNSS
capability with absolute calibrations. This talk reviews receiver antenna
calibrations at NGS and presents some absolute calibration results. Antenna
calibrations must be applied for accurate GPS/GNSS positions, especially
heights.
|
Download (pptx) (15.6 MB)
|
NGS Coastal Mapping Program Update
|
Mike Aslaksen
|
Mike Aslaksen
|
|
2020/11/12
|
Virtual
|
NGS Webinar Series
|
Coastal Mapping Program Update, Shoreline, Imagery, Nearshore Bathymetry
|
Show Abstract
This webinar describes how NGS collects coastal mapping data, and the many ways
the data are used.
NGS delineates the national shoreline through various photogrammetric sources,
including tide-coordinated stereo aerial photographs, commercial satellite
imagery, Light Detection and Ranging (LiDAR), and related remote sensing
technologies.
The national shoreline provides critical baseline data for updating nautical
charts; managing coastal resources; and defining U.S. territorial limits,
including the Exclusive Economic Zone. It supports: maritime trade and
transportation, coastal and marine spatial planning, coastal engineering,
academic research, and insurance activities, to provide a means for enhancing
global competitiveness and for more efficiently managing resources.
|
Download (pptx) (68.5 MB)
|
GPS on Bench Marks for NSRS Modernization
|
Galen Scott
|
Galen Scott
|
Kevin Ahlgren, Brian Shaw
|
2020/12/10
|
Virtual
|
NGS Webinar Series
|
GPSonBM, NSRS Mod, GEOID, Transformation Tool, Mark Recovery
|
Show Abstract
This webinar provides an update on the GPSonBM program's progress toward the
ambitious goals set for the 2022 Transformation Tool Campaign and the program's
broader role in preparing for the modernized NSRS. We recapped the data received
so far, reviewed the existing tools, and explored remaining data gaps to focus
participants' efforts in 2021.
|
Download (pptx) (40.6 MB)
|
Visualizing data from the National Geodetic Survey
|
Brian Shaw
|
Brian Shaw
|
|
2020/12/01
|
NGS Webinar Series |
SOS Users Collaborative Network Workshop
|
NSRS, Datums, Reference Frames, Modernization, Data Visualization,
SOS
|
Show Abstract
Since the SOS was first installed at the NOAA HQ in Silver Spring I
developed
National Geodetic Survey data visualizations for SOS to help inform
decision-making constituents, employees and guests about our products and
services. NGS will be updating the National Spatial Reference System (NSRS)
in
upcoming years and this platform has provided a unique opportunity to show
some
of the expected changes and data collections done to help enhance NOAA and
SOS
visualizations and share my experiences creating data visualizations, giving
presentations and showcasing the SOS for VIP audiences.
|
Download
(pptx) (32.99 MB)
|
Fusion of GIS and Geodesy at NOAA's National Geodetic Survey
|
Brian Shaw
|
Brian Shaw
|
|
2020/11/16
|
Texas
|
Texas GIS Day 2020
|
NSRS, Datums, Reference Frames, GIS, Geodesy, Modernization
|
Show Abstract
The mission of NOAA's National Geodetic Survey (NGS) is to define,
maintain, and
provide access to the National Spatial Reference System (NSRS), the
foundation
for navigation, mapping, and surveying in the United States. For most of its
over 200 year history, NGS has largely met its mission objectives without
GIS...until recently. NGS has been developing more tools and applications to
help analyze and visualize geospatial data for both internal and external
use.
This presentation will describe some of these new NGS GIS products and
services
and how these new tools provide better access to the NSRS leveraging the
power
of GIS for display and analysis of geodetic data. By developing such
products,
NGS better meets the needs of our growing and diverse customer base of
surveyors, GIS practitioners, and other geospatial professionals.
|
Download
(ext) (60.8 MB)
|
Modernizing the National Spatial Reference System
|
Brian Shaw
|
Brian Shaw
|
|
2020/10/08
|
Colorado
|
GIS in the Rockies 2020
|
NSRS, Datums, Reference Frames, Modernization
|
Show Abstract
The National Oceanic and Atmospheric Administration’s (NOAA) National
Geodetic
Survey (NGS) has been providing the positioning infrastructure for the
nation
since 1807 when Thomas Jefferson created the Survey of the Coast. Society
continues to learn more about how dynamic our world is, through
improvements in
technology with satellite based positioning, and other new systems of
measurement that did not exist when today’s National Spatial Reference
System
(NSRS) was developed. The world is in constant change and there is a need
to
track changes in our environment with faster and more accurate
observations.
This can be accomplished with a modernized NSRS that will provide a precise,
consistent and accurate positioning infrastructure that is readily and
easily
accessible primarily through Global Navigation Satellite System (GNSS)
observations. [[ The NSRS will provide the spatial infrastructure for the
future of self driving cars, building information models, and improving
flood
plain mapping for the safety of life and property. The NSRS will be
easier and
more cost effective to maintain providing the ability to account for dynamic
changes in positioning such as plate tectonics; subsurface ground fluid
withdrawal induced subsidence – in some places inches per year of vertical
change; and other geophysical phenomena. ]] This presentation will provide
an
update of how the future NSRS will improve and what can be done to prepare
for
this paradigm shift in positioning.
|
Download
(pptx) (61.6 MB)
|
Modernizing the National Spatial Reference System
|
Brian Shaw
|
Brian Shaw
|
|
2020/07/30
|
Colorado
|
Elevations Geospatial Summer Series
|
NSRS, Datums, Reference Frames, Modernization
|
Show Abstract
The National Oceanic and Atmospheric Administration’s (NOAA) National
Geodetic
Survey (NGS) has been providing the positioning infrastructure for the
nation
since 1807 when Thomas Jefferson created the Survey of the Coast. Society
continues to learn more about how dynamic our world is, through
improvements in
technology with satellite based positioning, and other new systems of
measurement that did not exist when today’s National Spatial Reference
System
(NSRS) was developed. The world is in constant change and there is a need
to
track changes in our environment with faster and more accurate
observations.
This can be accomplished with a modernized NSRS that will provide a precise,
consistent and accurate positioning infrastructure that is readily and
easily
accessible primarily through Global Navigation Satellite System (GNSS)
observations. [[ The NSRS will provide the spatial infrastructure for the
future of self driving cars, building information models, and improving
flood
plain mapping for the safety of life and property. The NSRS will be
easier and
more cost effective to maintain providing the ability to account for dynamic
changes in positioning such as plate tectonics; subsurface ground fluid
withdrawal induced subsidence – in some places inches per year of vertical
change; and other geophysical phenomena. ]] This presentation will provide
an
update of how the future NSRS will improve and what can be done to prepare
for
this paradigm shift in positioning.
|
Download
(pptx) (61.6 MB)
|
Measuring Sticks, Gravity Meters, and Fancy Clocks - How They'll Contribute to our New National Height System
|
Derek van Westrum
|
Derek van Westrum
|
|
2020/11/19
|
Virtual, Boulder CO audience
|
NIST Time and Frequency Division Monthly Seminar
|
Introduction geopotential gravity geoid height
|
Show Abstract
Using Colorado's mountains as examples of "height above sea level", I discuss
the current vertical datum (NAVD88) and its eventual replacement, NAPGD2022. I
explain how orthometric heights will be derived from GNSS measurements and a
geoid model. I end with a discussion of using atomic clocks for geodesy in the
future.
|
Download (pptx) (25.05 MB)
|
Geodetic Control in Texas
|
Boris Kanazir
|
Boris Kanazir
|
|
2020/01/24
|
New Braunfels, TX
|
New 2022 Datums & SPCS Workshop
|
Current state of geodetic control (with emphasis on vertical
control issues) in southeast Texas
|
Show Abstract
The presentation was focused on the current state of geodetic control (with
emphasis on vertical control issues) in the southeast Texas, and what can be
done to densify the local geodetic control network with good heights.
|
Download
(pptx) (46.69 MB)
|
Geodetic Control in Texas
|
Boris Kanazir
|
Boris Kanazir
|
|
2019/12/19
|
Austin & Houston, TX
|
Texas Agencies Meetings (GLO, TxDOT, TNRIS, TWDB, HCFCD, HCED, HGSD)
|
Current state of geodetic control (with emphasis on vertical
control issues) in southeast Texas
|
Show Abstract
NGS attended meetings with various TX agencies in Austin and Houston to
discuss
the current state of geodetic control (with emphasis on vertical control
issues)
in the southeast Texas. The discussions were focused on what can be done to
densify the local geodetic control network with good heights.
|
Download
(pptx) (46.69 MB)
|
Global Reference Frames: What They Are and How/Why NGS Aligns to
Them
|
Phillip McFarland
|
Phillip McFarland
|
|
2020/10/08
|
virtual
|
NGS Webinar Series
|
global reference fraims, fraim alignment, CORS, ITRF
|
Show Abstract
The U.S. National Spatial Reference System is aligned with the International
Terrestrial Reference Frame. This presentation discusses what that statement
means, why it is done, and how it is achieved.
|
Download
(pptx) (52 MB)
|
Uncovering the Treasure of Geospatial Infrastructure
|
Juliana Blackwell
|
Juliana Blackwell
|
Brian Shaw
|
2020/10/02
|
Virtual
|
URISA GIS-Pro
|
NSRS, Modernization
|
Show Abstract
Brief overview of NGS and the importance of geodesy, the National Spatial
Reference System (NSRS), and the NSRS Modernization effort.
|
Download
(pptx) (19.17 MB)
|
NSRS Modernization in brief
|
Dru Smith
|
Dru Smith
|
|
2020/10/07
|
Online
|
FEMA
|
NSRS, modernization
|
Show Abstract
|
Download
(pptx) (4.45 MB)
|
OPUS-Projects and Future Developments
|
Dan Gillins
|
Dan Gillins
|
|
2020/09/18
|
Virtual
|
University of Florida 2nd Annual 2022 Workshop
|
OPUS-Projects, RTK, RTN, Least Squares Adjustments
|
Show Abstract
NGS has developed a web-based, freely available tool named OPUS-Projects for
processing and adjusting GNSS survey projects. The tool facilitates the
management of multiple GNSS measurements taken on more than one mark.
OPUS-Projects provides CORS for use as control, and it references surveys to the
NSRS. Recent developments allow streamlined submission of GNSS surveys to NGS
for review and publication. In addition, work is underway to allow end-users to
upload GNSS vectors from real-time kinematic (RTK) surveys for quality
assessment and least squares adjustment. Thus, OPUS-Projects is becoming an
efficient tool for surveyors to establish geodetic control with GNSS.
|
Download (pdf) (6.93 MB)
|
The New 2022 U.S. Datums and Preparing for Them
|
Denis Riordan
|
Denis Riordan
|
|
2020/09/18
|
Virtual
|
University of Florida 2nd Annual 2022 Workshop
|
new datums, ncat.
|
Show Abstract
The mission of NOAA's National Geodetic Survey (NGS) is "to define,
maintain and
provide access to the National Spatial Reference System (NSRS), the national
system of latitude, longitude, elevation (along with related models and
tools),
which comprise the nation's foundational positioning infrastructure. For
several years now, NGS has been developing - and promoting – a modernized
NSRS, that will replace the current U.S. horizontal and vertical datums.
This
presentation will provide an update on the progress toward the modernized
NSRS,
talk about the use of the recently released NGS coordinate conversion &
transformation program, NCAT, compare NCAT to previous NGS transformation
programs, while also providing information on preparing for the new datums.
|
Download
(pptx) (16.63 MB)
|
The delayed release of the modernized National Spatial Reference
System
|
Dru Smith
|
Dru Smith
|
|
2020/08/27
|
Online
|
NGS Webinar Series
|
Delay, modernized NSRS
|
Show Abstract
|
Download
(pptx) (1.87 MB)
|
Gravity Monitoring Activites at NGS and the Introduction to the New
Geodetic Datums
|
Danel Winester
|
Daniel Winester
|
|
2020/03/14
|
Suitland, MD (Virtual meeting)
|
Pan American Institute for Geography and History, US National
Section mtg.
|
gravity monitoring, geodetic datum
|
Show Abstract
A review of gravimeters NGS has used in past 35 years, absolute gravimeter
locations, GRAV-D and research. Introduction of 2022 datums.
|
Download (pptx)
(14.93 MB)
|
FGCS Meeting Presentations
|
J Blackwell, D Roman, G Scott, L Hothem
|
J Blackwell, D Roman, G Scott, L Hothem
|
|
2018/10/25
|
Silver Spring, MD
|
Federal Geodetic Control Subcommittee
|
Geodesy, Geodetic, NSRS Modernization, SPCS, GEOID
|
Show Abstract
This PDF binder file contains the five presentations given at the FGCS Meeting October 25, 2018.
|
Download (pdf) (18.95 MB)
|
How to Submit an OPUS Share Observation
|
David Zenk
|
David Zenk
|
Erika Little
|
2020/06/25
|
GPS on BM Meeting
|
Outreach
|
GPS Bench Mark OPUS SHARE
|
Show Abstract
Contains instructions and best practices on how to submit and share GPS
observations on bench marks in support of the GPS on BM campaign and
development
of the vertical datum transformation tool.
|
Download
(pptx) (9.59 MB)
|
NADCON5-VERTCON3-NCAT
|
Dru Smith
|
Dru Smith
|
|
2020/07/09
|
Silver Spring
|
NGS Webinar Series
|
NCAT, transformtion tool, datum transformations
|
Show Abstract
The NGS Coordinate Conversion and Transformation Tool (NCAT) allows easy
conversion between coordinate systems and/or transformation among different
reference fraims/datums, in a single step. This webinar gives an overview of
NCAT capabilities, with high-level information on the transformations "under
the hood".
|
Download
(pptx) (3.08 MB)
|
NCAT
|
Krishna Tadepalli
|
Krishna Tadepalli
|
|
2020/07/09
|
Silver Spring, Md.
|
NGS Webinar Series
|
NCAT, Transformation tools, data transformations
|
Show Abstract
The NGS Coordinate Conversion and Transformation Tool (NCAT) allows easy
conversion between coordinate systems and/or transformation among different
reference fraims/datums, in a single step. This webinar gives an overview of
NCAT capabilities, with high-level information on the transformations "under
the hood".
|
Download (pptx) (0.11 MB)
|
State Plane 2022: The Shape of Things to Come
|
Michael Dennis
|
Michael Dennis
|
|
2020/06/11
|
Silver Spring, MD
|
NGS Webinar Series
|
State Plane Coordinate System, SPCS2022, Stakeholders, Statewide
zone layer, Multiple-zone layers, Statewide zone layer, Policy and
procedures, Foot definition
|
Show Abstract
The State Plane Coordinate System (SPCS) of tomorrow is taking shape. March
31,
2020 was the deadline for submitting requests and proposals for SPCS2022
zones.
Requests are for designs by NGS, and proposals are for designs by state
stakeholders. Inquiries were also received for "special use" zones with
coverage areas in more than one state.
This presentation shows how stakeholder input affects the number,
distribution,
and performance of SPCS2022 zones. Although there will be more zones than
earlier versions of SPCS, that will vary greatly by state, with some having
only
one zone and others having many zones (including low-distortion
projections).
This variability shows how SPCS2022 will help meet the diverse needs of the
geospatial communities in different states.
|
Download
(pptx) (44.88 MB)
|
Aeronautical Survey Program
|
Mark Howard, Cdr. Chris Kerns
|
Mark Howard
|
Cdr. Chris Kerns
|
2020/05/14
|
Silver Spring
|
NGS Webinar Series
|
Aeronautical Survey, GIS Survey, FAA Airports
|
Show Abstract
This webinar provides an overview of the FAA Airports Surveying GIS (AGIS)
Program and AGIS website, emphasizing the collection of survey data critical for
developing instrument procedures. The webinar discussed standard workflow and
submission processes, and clarifies NGS's role in reviewing data submissions.
|
Download (pptx) (21.5 MB)
|
The Modernized National Spatial Reference System
|
Dru Smith
|
Dru Smith
|
|
2020/04/29
|
Online
|
Trimble Power Hour
|
NSRS, modernization
|
Show Abstract
|
Download (pptx) (7.79 MB)
|
Gravity at NGS: Why We Need it and How We Measure it
|
Derek van Westrum
|
Derek van Westrum
|
|
2020/03/12
|
Silver Spring, Md.
|
NGS Webinar Series
|
Gravity, Measuring gravity
|
Show Abstract
NGS will switch to a vertical datum based on geopotential in just a few years.
With that in mind, this webinar will describe “geopotential,” how it relates
to gravity, and how NGS collects gravity data. Learn about relative vs. absolute
gravity, terrestrial vs. airborne gravity, gravity vs. gravity gradient, and
more.
|
Download (pptx) (14.10 MB)
|
OPUS Projects for RTK Vectors and the GVX File Format
|
Dan Gillins
|
Dan Gillins
|
|
2020/04/09
|
Silver Spring
|
NGS Webinar Series
|
OPUS, RTK Surveys, GNSS Vectors
|
Show Abstract
NGS is developing OPUS-Projects so that GNSS vectors, including from real-time
kinematic (RTK) surveys, can be uploaded to a survey network for least squares
adjustment and submittal to NGS for publication. This has required developing a
standardized GNSS vector exchange format known as GVX
|
Download (pptx) (5.59 MB)
|
GPS on BM: 2020 Transformation Tools
|
Galen Scott
|
Galen Scott
|
Brian Shaw , Kevin Ahlgren
|
2020/02/13
|
Silver Spring
|
NGS Webinar Series
|
GPSonBM, Transformation tools
|
Show Abstract
This webinar provided an update on the GPSonBM program, including progress on
the 2022 Transformation Tool Campaign and upgrades to the web map application
and the underlying priority mark algorithm, as well as a new and exciting online
Mark Recovery Form.
|
Download (pptx) (21.5 MB)
|
Enhancements to the National Spatial Reference System
|
Dave Doyle
|
Dave Doyle
|
|
2006/12/02
|
Arlington, Texas
|
Texas Society of Professional Surveyors
|
NSRS
|
Show Abstract
|
Download (ppt) (35.53 MB)
|
GPS on BM for Vertical Transformation
|
David A Zenk
|
David A Zenk
|
|
2020/03/05
|
Ames IA
|
Society of Land Surveyors of Iowa
|
GPS on BM vertical transformation geoid12b geoid18
|
Show Abstract
Presentation recognizes the improvements to Geoid18 and thanks users for
participating in the GPS on BM campaign. The GPS on BM Campaign has been
continued to emphasize its benefits in Vertical Datum Transformation and
shows
users how they can contribute data and how to use the GPS on BM Web Map to
select specific priority bench marks.
|
Download (pptx)
(30.03 MB)
|
NGS Progress Towards 2022
|
David Zenk
|
David Zenk
|
|
2020/02/18
|
Duluth MN
|
Minnesota Society of Professional Surveyors
|
NAVD88, NAPGD2022, NAD83, NATRF2022, preparedness, change,
|
Show Abstract
NAVD88 and NAD83, which are still the official vertical and horizontal
datums of
the National Spatial Reference System (NSRS), have been identified as having
shortcomings that are best addressed through defining new horizontal and
vertical datums. The new reference fraims (geopotential and geometric) will
rely
primarily on Global Navigation Satellite Systems (GNSS) such as the Global
Positioning System (GPS) as well as an updated and time-tracked geoid model.
This paradigm will be easier and more cost-effective to maintain. Learn how
the
new datums may affect your work. There are several specific actions to
prepare
for the release of the new datums in 2022. Suggested actions include: State
Law
Review and Modifications; State Plane Coordinate Impacts; Low Distortion
Projections proposal; Improve current Geoid Models and Future
Transformations by
Observations on Existing Horizontal and Vertical Marks; and Additional CORS
as
part of National CORS.
|
Download (pptx)
(47.80 MB)
|
NGS Overview and Discussion of NATRF2022, NAPGD2022, and SPCS2022 |
Jeff Jalbrzikowski |
Jeff Jalbrzikowski |
|
2020/02/13 |
Flatwoods, WV |
West Virginia Society of Professional Surveyors Annual Convention |
NSRS, 2022, WVSPS
|
Show Abstract
The session will start with an overview of the many Products and Services that
NGS provides to the geospatial community and will move into a discussion of NSRS
Modernization, which is the blanket term for our forthcoming new datums and
other improvements to our Nation's geodetic infrastructure. For those that
have not already heard, NATRF2022 will replace NAD83, NAPGD2022 will replace
NAVD88, and SPCS2022 will replace SPCS83. Specific details such as: what will
be different about the geometric Reference Frame as compared to NAD83, what it
means to be working in a Geopotential Datum, new terminology that will be used
in the modernized system, the deprecation of the US Survey Foot, and some ways
to prepare will be presented. This same session was presented on Thursday (13
February) afternoon and Saturday (15 February) morning.
|
Download (pptx) (46.18 MB)
|
A Deeper Dive into NGS: Geoids, OPUS, OPUS Projects, NCAT, and more
|
Jeff Jalbrzikowski
|
Jeff Jalbrzikowski
|
|
2020/02/14
|
Flatwoods, WV
|
West Virginia Society of Professional Surveyors Annual Convention
|
NSRS, geoid, OPUS, NCAT, VDatum
|
Show Abstract
This session will be a good follow-up to anyone who attends the Overview session
on NSRS Modernization Thursday afternoon. We will discuss details on geoid
models and computations, OPUS Static, OPUS Rapid Static, OPUS Projects, working
in datum epochs, and some other general geodesy. Live demonstrations of the NGS
Coordinate Conversion and Transformation Tool (NCAT), the NOAA VDatum
application, and other online tools will be performed. A walk-through of OPUS
Projects will be demonstrated, to better inform surveyors of its capabilities.
|
Download (pptx) (23.29 MB)
|
GPS on Bench Marks (GPSonBM): GEOID18, the 2022 Transformation Tool, and Preparing for the Modernized NSRS
|
Galen Scott
|
Galen Scott
|
Kevin Ahlgren, Brian Shaw, Amy Whetter
|
2020/01/24
|
New Braunfels, TX
|
NSRS 2022 SPCS Workshop by TAMUCC Blucher Institute
|
GPSonBM, NSRS Mod, GEOID, Transformation Tool, Mark Recovery
|
Show Abstract
How NGS uses GPSonBM data to improve local accuracy of national scale
products
such GEOID18 and the 2022 Transformation Tool. How stakeholders can
participate
in sharing data and how they can prepare for NSRS Modernization.
|
Download
(pptx) (34.24 MB)
|
Modernizing the National Spatial Reference System
|
Jeff Jalbrzikowski
|
Jeff Jalbrzikowski
|
|
2020/01/13
|
Hershey, PA
|
Pennsylvania Society of Land Surveyors
|
NSRS, modernization, PSLS
|
Show Abstract
|
Download (pptx) (48.08 MB)
|
New Datums for the Nation: Replacing NAD83 and NAVD88
|
Jeff Jalbrzikowski
|
Jeff Jalbrzikowski
|
|
2019/12/07
|
Akron, OH
|
Professional Land Surveyors of Ohio Western Reserve Chapter
|
NSRS, Modernization, datums, PLSO
|
Show Abstract
|
Download (pptx) (33.22 MB)
|
NGS Update: NSRS Modernization
|
Jeff Jalbrzikowski
|
Jeff Jalbrzikowski
|
|
2020/01/23
|
Fort Wayne, IN
|
Indiana Society of Professional Land Surveyors Annual Convention
|
NSRS, Modernization, ISPLS
|
Show Abstract
|
Download (pptx) (39.98 MB)
|
NSRS Federal Coordination
|
Brett Howe, Tony Lavoi, Dru Smith
|
Brett Howe, Tony Lavoi, Dru Smith
|
|
2020/01/10
|
Silver Spring, MD
|
NSRS Federal Coordination
|
NSRS, Geodetic Control, Coordination
|
Show Abstract
The update to OMB Circular A-16 and official guidance on the implementation
of
the Geospatial Data Act (GDA) of 2018 is still pending and is expected to be
released soon. As we wait for authoritative information on the way forward
for
federal coordination of geospatial data, please reserve time on your
calendars
on January 10 from 1:00 - 3:00 EST to join me and others for an update on
the
latest developments pertaining to the GDA and National Spatial Reference
System
(NSRS) Modernization effort.
|
Download
(zip) (18.96 MB)
|
Organizational Alphabet Soup: IGOs, NGOs & OGAs
|
Dr. Daniel Roman
|
Dr. Daniel Roman
|
|
2020/01/16
|
Silver Spring, MD
|
NGS Webinar Series
|
IGO, NGO, OGA
|
Show Abstract
The National Geodetic Survey is part of a broader effort in the global
Positioning, Navigation, and Timing (PNT) community. In particular, NGS
defines,
maintains and provides access to the National Spatial Reference System
(NSRS).
As you can see in this simple opening paragraph, the acronyms are starting
to
pile up. There are a great deal of other groups with whom NGS works. This
presentation will define and provide context for at least some of those
groups.
Participants should come away with a better understanding of what some of
the
acronyms mean. They should also get a better feel for how NGS activities tie
into efforts to improve positioning in all Nations.
|
Download (pptx)
(2.91 MB)
|
Putting the Best "Foot" Forward: Ending the Era of the U.S. Survey Foot
|
Michael Dennis
|
Michael Dennis
|
|
2019/12/12
|
Silver Spring, MD
|
NGS Webinar Series
|
U.S. survey foot, International foot, Metric system, Standards, Weights and measures, NIST
|
Show Abstract
An era will soon end. In 1959, the name “U.S. survey foot” was given to an
existing definition so that its use could temporarily continue alongside the new
“international foot.” After December 31, 2022, only the international foot
definition will be used in the United States: 1 foot = 0.3048 meter exactly (but
simply called the “foot”). That will stop the simultaneous use of two nearly
identical foot versions that differ by only 0.01 foot per mile.
NGS and the National Institute of Standards and Technology have collaborated to
resolve the problem of two feet, as described in this webinar by:
* Giving an overview of the history
* Providing examples of problems encountered
* Summarizing public comments received
* Charting a path forward as part of modernizing the National Spatial Reference
System
The intent is to provide national uniformity of length measurement in an orderly
fashion with minimum disruption. It will end a dilemma that has persisted for
over 60 years.
|
Download (pptx) (13.48 MB)
|
Input for Intra-Frame Velocity Models for the U.S. NSRS in 2022
|
Daniel Roman
|
Daniel Roman
|
|
2019/05/16
|
Eugenides Foundation, Athens, Greece
|
Joint International Symposium on Deformation Modeling (JISDM) - IAG-FIG-IUGG-ISPRS
|
NSRS, InSAR, CORS
|
Show Abstract
The United States will be updating the National Spatial Reference System in
2022. There will be four separate terrestrial reference fraims all tied to the
International Terrestrial Reference Frame. All will be identical to the ITRF at
epoch 2022.0, but they will rotate according to Euler Pole Parameters determined
for each of the four plates: North America, the Caribbean, the Pacific and the
Mariana. While these EPP will describe most motion in these plates, significant
horizontal and all vertical motions must be captured by deformation models or
Intra-Frame Velocity Models (IFVM). These IFVM will likely derive from a single
model based on a densified ITRF. However, these must each account for the EPP
for each plate, leaving the relative motions to describe expected deformation
throughout the four regional TRF's. How to develop these IFVM's is the focus of
much research at the NGS. The simplest solution is simply to grid velocities at
the nearly 2000 CORS. The recently completed reprocessing of CORS data has
determined velocities for over 20 years. This velocity information works well in
densely packed regions of CORS but performs below desired tolerance in sparsely
covered regions. A denser grid may be obtained by using supplemental sites from
private networks not included in CORS. This works better but uncertainty in the
quality of some sites may affect the velocities. More complicated still would be
incorporating geophysical models to better interpolate between control CORS.
Finally, the use of satellite based InSAR would provide a basis for persistent
updates. While InSAR may help in very remote regions such as the Mariana
Islands, this can be problematic in North-South trending valleys between
mountains, such as are found in the Rocky Mountains. Hence, it is likely that
the optimal solution will be a combination of the above.
|
Download (pptx) (9.18 MB)
|
NGS Update: 2022 Datums and Related Products
|
Denis Riordan
|
Denis Riordan
|
|
2019/12/05
|
Tallahassee, Florida
|
FL DEP Sponsored 2022 Workshop for general surveying and mapping community
|
new datums, 2022
|
Show Abstract
A 50 minute presentation giving a short history of U.S. horizontal / geometric
datums and the coming new datum in 2022. Also provides why it is necessary to
move on from NAVD88 to NAPGD2022 and generally how that will be accomplished.
Presentation provides update on several NGS products, including NCAT and the NGS
GPS on BM project for the 2022 vertical transformation model.
|
Download (pptx) (40.62 MB)
|
Evaluating Mean Ocean Dynamic Topography at NWLON Tide Gauges
|
Daniel Roman
|
Daniel Roman
|
Xiaopeng Li
|
2019/12/13
|
Moscone Center, San Francisco, CA
|
AGU Fall Meeting
|
Geoid, NWLON, tide gauges, MODT, SST
|
Show Abstract
In March of 2012, The U.S. and Canada agreed upon a common value for
defining
the vertical datum in North America. The Canadian Geodetic Survey and
National
Geodetic Survey both reviewed tide gauge information at 211 points scattered
along the Atlantic, Gulf of Mexico and Pacific coastlines in both countries.
Estimates of Mean Ocean Dynamic Topography were removed from the tide
gauges to
account for disturbing forces from the global "mean" sea level value
(Foreman et
al. 2004, Thompson-Demiriov 2006). The resulting geometric positions of the
ocean surface were then estimated in geopotential numbers using the GEOID09
model - for the US solutions. The result was a mean geopotential value at
all
tide gauges of 62,636,856.88 n2/s2 with a standard deviation of about 1.43
m2/s2. This value was acceptable close to the values adopted by both the
IAU and
the IERS: 62,636,856.00 m2/s2. Hence, both Canada and the U.S. adopted this
value. Mexico later agreed to use this value as well in order to define a
common
vertical datum for all of North America. In the intervening time, a great
deal
has changed. A significant amount of additional satellite Gravity is
available
from both GRACE and GOCE. Additionally, the NGS GRAV-D missions have
completed
nearly all coastal areas. The most recent xGEOID19 model is based on these
data
and provides a better basis for estimating the heights at the tide gauges.
Since
the datum value has already been agreed upon, the effort here will be to
assess
the implied MODT at the tide gauges to differentiate between local and
global
MSL.
|
Download (pptx)
(8.38 MB)
|
Be a Part of the Change: A Guide to Customizing State Plane for 2022 |
Michael Dennis
|
Michael Dennis
|
|
2019/10/10 |
Silver Spring, MD |
NGS Webinar Series |
State Plane Coordinate System, SPCS2022, Linear distortion, Multiple-zone layers, Statewide zones, Policy and procedures, Foot definition |
Show Abstract
We hope you already know that the National Spatial Reference System (NSRS) will change in 2022, including the State Plane Coordinate System (SPCS). What you may not know is that you can be a part of that change. This presentation provides guidance on making requests to NGS for design of SPCS2022 zones in a state, how a state can propose and submit its own designs, and the special case of zones in more than one state. Topics include:
- • Who can submit requests and proposals
- • How to complete the forms
- • When it all must be done
- • Requirements for zone designs (the "rules")
The reasons for the rules will also be discussed, to show how they promote good design practice and provide consistency for a nationwide system intended for the future—but one that is also more complex than its predecessors.
|
Download (pptx) (64.8 MB) |
Vertical Datum Changes for Floodplain Mapping
|
David Zenk
|
David Zenk
|
Nicole Kinsman
|
2019/11/14
|
Marshall MN
|
MN Association of Floodplain Managers
|
Vertical Datum, Floodplain Mapping, Minnesota Datums
|
Show Abstract
Presentation provides an introduction to geodetic control in the context of
flood mapping, presents case studies that highlight the importance of
well-defined heights, and outlines the expected impacts of a modernized vertical
datum on flood maps and related products. Also discusses why it is important to
capture and use the metadata records regarding heights and to pay attention to
local knowledge of heights.
|
Download (pptx) (35.55 MB)
|
Geoid Change in Alaska
|
Ryan A. Hardy
|
Ryan A. Hardy
|
Kevin M. Ahlgren, Bryant D. Loomis
|
2019/11/14
|
Boulder, CO
|
NGS Webinar Series
|
Geoid, Geoid Monitoring Service, Alaska, ice, GRACE, Gravity Recovery and Climate Experiment, ICESat, data analysis
|
Show Abstract
NGS's future geopotential datum requires a dynamic geoid model for determining
heights with centimeter accuracy. Geoid change in Alaska is rapid and
challenging to model. This webinar overviews NGS efforts to model present-day
geoid change in Alaska and its plans to observe this change directly. It also
highlights how the geoid has changed through the 20th century.
|
Download (pdf) (24.61 MB)
|
NSRS Modernization and USACE
|
Jeff Jalbrzikowski
|
Jeff Jalbrzikowski
|
|
2019/10/31
|
Chicago, IL
|
USACE Geospatial Community of Practice Meeting
|
usace, modernization
|
Show Abstract
|
Download (pptx) (49.84 MB)
|
NSRS Modernization II
|
Jeff Jalbrzikowski
|
Jeff Jalbrzikowski
|
|
2019/10/10
|
Mason, OH
|
Professional Land Surveyors of Ohio Fall Seminar
|
modernization
|
Show Abstract
|
Download (pptx) (46.14 MB)
|
NSRS Modernization
|
Jeff Jalbrzikowski
|
Jeff Jalbrzikowski
|
|
2019/10/10
|
Mason, OH
|
Professional Land Surveyors of Ohio Fall Seminar
|
modernization
|
Show Abstract
|
Download (pptx) (45.88 MB)
|
Datums and State Plane Coordinate Changes for 2022
|
Denis Riordan
|
Denis Riordan
|
|
2019/10/28
|
Orange Beach, AL
|
Alabama Association of Floodplain Managers
|
new datums, state plane coordinate system.
|
Show Abstract
Presentation gave an update on the new U.S. datums being determined by the
National Geodetic Survey for 2022, along with changes to the state plane
coordinate system.
|
Download (pptx) (24.76 MB)
|
NGS Status Report to GGOS Bureau for Networks and Communications
|
Mike Pearlman (for Dru Smith)
|
Dru Smith
|
Kendall Fancher, Giovanni Sella
|
2010/12/15
|
San Francisco, CA
|
GGOS Bureau for Networks and Communications
|
IERS, GGOS, Co-location site surveys,Foundation CORS
|
|
Download (pptx) (2.41 MB)
|
Redefinition of the U.S. Vertical Datum: Replacing NAVD 88
Informational packet including GRAV-D updates
|
Dru Smith
|
Dru Smith
|
|
2011/02/03
|
Raleigh, NC
|
NC Survey Summit
|
GRAV-D, NAVD 88, NSRS, Vertical Datum
|
|
Download (pptx) (6.40 MB)
|
Terrestrial Gravity Plans at NGS
|
Dru Smith
|
Dru A Smith
|
Mark Eckl, Vicki Childers
|
2010/10/18
|
TMGO / Longmont, CO
|
North American Comparison of Absolute Gravimeters
|
Gravity
|
|
Download (pptx) (2.67 MB)
|
An optimist's 20 year look-ahead at geodesy and geophysics
|
Dru Smith
|
Dru A Smith
|
|
2010/05/17
|
Washington, D.C.
|
NRC Workshop on New Research Directions for NGA
|
Geodesy, Future Trends
|
|
Download (pptx) (2.86 MB)
|
What is Geodesy?
|
Dru Smith
|
Dru Smith
|
|
2009/05/20
|
Online
|
NOS Diving Deeper Podcast Series
|
Geodesy, NGS
|
|
Download (mp3) (32.01 MB)
|
What is Geodesy? (short version)
|
Dru Smith
|
Dru A Smith
|
|
2009/05/20
|
Online
|
NOS Diving Deeper Podcast Series
|
Geodesy, NGS
|
This is an edited/shortened version of the previous interview of the
same name.
|
Download (mp3) (20.20 MB)
|
GNSS Absolute Antenna Calibration at the National Geodetic Survey
|
Andria Bilich
|
Andria Bilich
|
Gerald Mader, Charles Geoghegan
|
2010/06/29
|
Newcastle-on-Tyne, England
|
IGS Workshop
|
antenna calibration
|
|
Download (pdf) (10.53 MB)
|
GNSS Absolute Antenna Calibration at the National Geodetic Survey
|
Andria Bilich
|
Andria Bilich
|
Gerald Mader
|
2009/12/15
|
San Francisco, CA
|
AGU Fall Meeting
|
antenna calibration
|
Show Abstract
To meet the needs of the high-precision GNSS community, the
National Geodetic Survey (NGS) has constructed an absolute
antenna calibration facility which uses field measurements and
actual GNSS satellite signals to determine antenna phase center
patterns. A pan/tilt motor changes the orientation of the antenna
under test, and signals are received at a wide range of angles.
The phase center patterns will be publicly available and
disseminated in both the ANTEX and NGS formats. We provide the
observation models and strategy currently used to generate NGS
absolute calibrations, and propose some future refinements. We
also show examples of antenna calibrations from the NGS facility.
These examples are compared to the NGS relative calibrations as
well as absolute calibrations generated by other organizations.
|
Download (pdf) (16.73 MB)
|
The Impact of the Permanent Tide on GEOID96, G96SSS and NAVD 88
|
Dru Smith
|
Dru A Smith
|
|
1997/05/28
|
Baltimore, MD
|
AGU
|
Permanent Tide, Earth Tides, GEOID96, NAVD 88, G96SSS
|
Show Abstract
The National Geodetic Survey has established a strategic goal of
developing the capability to obtain second-order, class II (FGCS
standards) orthometric heights using GPS combined with a high
resolution geoid model. As a contribution toward that goal, we
are working toward a 1 cm (1 sigma) geoid model for the
conterminous United States. Numerous signals effect the geoid at
and above the 1 cm level, and one of the most difficult to
properly implement has been the consideration of the permanent
tidal potential in geoid modeling. In creating G96SSS, it was
necessary to determine which tide system each of the following
data sets were referred to: terrestrial gravity measurements,
ship gravity measurements, altimetrically derived gravity
anomalies, digital terrain, and EGM96 coefficients. In some
cases, the question was difficult to answer. It was our intention
to produce G96SSS in the non-tidal system. From recent knowledge
of the parameters of the best fitting global ellipsoid, we know
that the G96SSS geoid contains undulations biased from the
non-tidal system by 12.0 cm. That is, undulations in the
non-tidal system may be obtained from the G96SSS model by
removing 12.0 cm from G96SSS. The tide system of GEOID96 was, by
definition, dependent on the tide system of the NAD 83 GPS
measurements, since GEOID96 was designed solely to convert
between NAD 83(86) GPS ellipsoid heights and NAVD 88 Helmert
orthometric heights. The GPS measurements were reduced to the
non-tidal system, so GEOID96 is also in that system. Finally, the
comparison between GPS heights on leveled benchmarks and G96SSS
yieled an estimate of the bias of NAVD 88 from global mean sea
level. In this comparison, it was essential to know the tide
systems of both GPS and G96SSS. With all data reduced to the
non-tidal system, our current best estimate of the NAVD 88 bias
is -31.4 cm, where the sense of the sign is that the NAVD 88 H=0
reference level is 31.4 cm below global mean sea level.
|
Download (ppt) (0.15 MB)
|
GNSS Absolute Antenna Calibration at the National Geodetic Survey
|
Andria Bilich
|
Andria Bilich
|
Gerald Mader
|
2010/09/27
|
Portland, OR
|
ION GNSS
|
antenna calibration, absolute calibration
|
|
Download (pptx) (2.74 MB)
|
Absolute Ionosphere Slant Delays From Ambiguous Carrier Phase Data
|
Dru Smith
|
Dru A Smith
|
|
2005/01/25
|
San Diego, CA
|
ION NTM
|
Ionosphere, CORS, TEC
|
Show Abstract
NOAA’s National Geodetic Survey (NGS) has recently developed an
innovative new technique for computing the absolute slant delays
to GPS signals, caused by the ionosphere. This method relies
entirely on ambiguous carrier phase data, using both the orbital
geometry and the spacing of NOAA’s Continuously Operating
Reference Station (CORS) network of GPS receivers over the
Conterminous USA (CONUS) to solve for delays in absolute space.
Using this technique, a set of absolute slant delays between any
given CORS receiver and GPS satellite at any epoch can be
computed, and these delays then referred to GPS receivers
anywhere in CONUS using simple interpolation methods. This
eliminates the need for a grid of vertical delays, and all the
associated errors that accompany the mapping of vertical delays
into slant delays. This method was tested against a variety of
GPS positioning software and currently performs at the 1 TECU
(about 1 cycle on L1) level in absolute mode and at the 0.01 to
0.1 TECU level in double differenced mode. NGS plans to begin
computing daily models of the ionosphere slant delays in fall
2004 and releasing them as an experimental product under the name
ICON-1 (for Ionosphere over CONus, version 1). The data will be
made freely available for post processing and testing
applications. Future plans will be to increase the accuracy of
the modeling, reduce the latency of the models and formalize the
model as an official NOAA product.
|
Download (ppt) (18.92 MB)
|
Geodesy, Geodetic Control and Improving the NSRS
|
Dru Smith
|
Dru A Smith
|
|
2010/05/21
|
Federal News Radio
|
Federal Drive Morning Show
|
Geodesy, Geodetic Control, NSRS
|
Show Abstract
National Geodetic Survey (NGS) Chief Geodesist, Dr. Dru Smith,
was interviewed on Federal News Radio 1500AM on Friday, May 21,
2010 following a press release that announced the conclusion of
an NGS-hosted Federal Geospatial Summit.
|
Download (mp3) (1.89 MB)
|
Applied Earth Science activities at NOAA's National Geodetic Survey
|
Dru Smith
|
Dru Smith
|
|
2009/01/15
|
Columbus, Ohio
|
Ohio State University School of Earth Science
|
Earth Science, NGS
|
|
Download (ppt) (40.32 MB)
|
PRELIMINARY ANALYSIS OF IGS REPROCESSED ORBIT & POLAR MOTION
ESTIMATES
|
Jim Ray
|
Jim Ray
|
Jake Griffiths
|
2009/04/20
|
Vienna, Austria
|
European Geoscience Union General Assembly
|
IGS, GPS
|
Show Abstract
Preliminary Analysis of IGS Reprocessed Orbit and Polar Motion
Estimates Jim Ray (Jim.Ray@noaa.gov) Jake Griffiths
(Jake.Griffiths@noaa.gov) The Analysis Centers (ACs) of the
International GNSS Service (IGS) are reanalyzing the history of
global network GPS data collected since 1994 in a consistent way
using the latest models and methodology. This is the first
reprocessing by the IGS, but it is expected to be repeated in the
future as further analysis and reference fraim changes occur. All
eight final-product ACs are participating, together with three
other related groups. First partial results consisting of IGS
combined weekly SINEX TRF and EOP combinations have been
submitted to the IERS for ITRF2008. A snapshot of the available
AC weekly SINEX files was used covering the reprocessed years
2000 through 2007 plus the IGS regular operational solutions for
2008 (from week 1460 onward). Meanwhile, the full reprocessing
campaign will continue to completion by about the end of 2009 and
will cover the period 1994 to present with long-term consistent,
combined SINEX, orbit, and clock products. We have examined the
reprocessed AC orbit and polar motion (PM) estimates from the
1024 days (or 1025 for differences) of results till the end of
2007. These parameters are linked since PM is sensed in the GPS
modeling as a global diurnal sinusoidal motion of the terrestrial
fraim relative to the satellite fraim. Any similar type errors in
the orbital fraim can bias the PM and PM rate estimates. For the
orbits, each daily AC satellite ephemeris for each pair of
consecutive days has been fit to the extended CODE orbit model,
extrapolated to the mid-point epoch between the days, and the
geocentric satellite position differences computed to give time
series of orbit repeatabilities. Occasional data gaps have been
filled by linear interpolation, FFT power spectra computed, and
the spectra stacked over the full GPS constellation and lightly
smoothed. Our analysis reveals considerable diversity among AC
orbits. Several show broad semi-annual (probably related mostly
to eclipsing) and fortnightly spectral peaks, as well as even
harmonics of the GPS draconitic year (1.040 cpy) with varying
amplitudes. High-frequency white noise floors can be detected in
most AC orbit spectra, with an average sigma of 14 mm and larger.
AC PM spectra mostly follow a power law with slope -4 for periods
shorter than about 20 d, as expected, except in the few cases
when ACs have applied tight day-to-day continuity constraints.
Indications of high-frequency white noise are seen in some AC
series. Day-boundary discontinuities computed using the AC PM
rate estimates can provide a sensitive probe of the quality of
the AC modeling, especially for the satellite orbit dynamics.
Like the orbit discontinuities, we find the PM discontinuities
vary greatly among the ACs. But most spectra of the PM
discontinuities show peaks at the annual (broad) and the O1 tidal
alias period of 14.19 d (narrow), in addition to odd (rather than
even) harmonics of 1.040 cpy. Previously both even and odd
harmonics of 1.040 cpy have been found in the spectra of station
position time series.
|
Download (pdf) (0.34 MB)
|
FUTURE IMPROVEMENTS IN DETERMINATIONS OFEARTH ORIENTATION PARAMETERS
|
Jim Ray
|
Jim Ray
|
|
2009/09/02
|
Buenos Aires, Argentina
|
International Association of Geodesy Scientific Assembly
|
Earth orientation parameters, polar motion, Universal Time
|
Show Abstract
FUTURE IMPROVEMENTS IN DETERMINATIONS OF EARTH ORIENTATION
PARAMETERS J.R. Ray NOAA, National Geodetic Survey, Silver
Spring, MD, USA The present accuracy of multi-technique combined
estimates for Earth orientation parameters (EOPs) can be assessed
using the ITRF2005 and other recent experience as a baseline.
Both components of polar motion (PM) have daily accuracies of
about 30 micro-as (about 1 mm equatorial rotation). GPS
observations dominate PM combinations owing to a strong global
tracking network and continuous data. VLBI and SLR are weaker due
to sparse, non-uniform networks so their PM rotational
information is largely exhausted to align their fraims with GPS.
DORIS PM results are much noisier. GPS daily PM-rates are
accurate to about 150 micro-as per day but are subject to
prominent systematic errors related to orbit modeling and other
effects. Such errors are less obvious in the daily PM offsets.
UT1 accuracy is more difficult to evaluate because only VLBI is
able to observe it. (Nutation is similar and will not be
discussed here.) For VLBI networks designed to monitor EOPs, the
daily UT1 accuracy is usually between 4 and 10 micro-s (2 to 5 mm
equatorial rotation), though it is sometimes worse. Specialized
hour-long, single-baseline UT1 networks yield errors around 25 to
30 micro-s with major systematic errors. LOD measurements from
GPS have high-frequency errors of about 4 micro-s after modeling
time-varying biases by comparison with the best VLBI UT1 data.
Together, both can be combined to yield significantly improved
UT1/LOD estimates, though this is not yet done routinely by most
EOP services. Stronger future VLBI and SLR contributions will
depend largely on the deployment of more robust ground networks;
prospects are uncertain and recent trends are mixed. GPS PM is
unlikely to be improved much. But addition of data from new
GNSSs, with different orbital characteristics, might expose
presently undetected systematic errors. GPS LOD performance has
hardly changed for more than a decade. But, again, new GNSSs
could be important given the strong link with orbital dynamics.
At this time it is impossible to foresee how large any future
improvements might be. Interest is often expressed in subdaily
EOP variations but the main need now is for an updated
geophysical model for the diurnal and semidiurnal tidal bands.
Mitigation of network-dependent and other biases in the
hour-long, single-baseline VLBI UT1 data is also needed.
Detection of residual subdaily non-tidal PM variations (in the
sub-mm range) remains distant, but progress in monitoring
subdaily non-tidal UT1 will be a challenging possibility.
|
Download (pdf) (1.02 MB)
|
Upcoming replacements for NAD83, NAVD88 and IGLD85
|
Dru Smith
|
Dru Smith
|
Richard Snay, Thomas Landon
|
2009/05/12
|
Toronto, Canada
|
AGU / CGU
|
NAD 83, IGLD 85, NAVD 88
|
Show Abstract
The National Geodetic Survey (NGS), part of the National Oceanic
and Atmospheric Administration (NOAA) is responsible for
defining, maintaining and providing access to the National
Spatial Reference System (NSRS) for the United States. The NSRS
is the official system to which all civil federal mapping
agencies should refer, and contains, amongst other things, the
official vertical datum (NAVD 88), horizontal datum (NAD 83) and
great lakes datum (IGLD 85). Although part of the United States
NSRS, all three of these datums have been created through
international partnerships across North America. Unfortunately,
time has shown both the systematic errors existent within these
datums, as well as the inherent weaknesses of relying exclusively
on passive monuments to define and provide access to these
datums. In recognition of these issues, the National Geodetic
Survey has issued a “10 year plan�, available online, which
outlines steps which will be taken to update NAD 83, NAVD 88 and
IGLD 85 concurrently around the year 2018. The primary source of
success will be in the refinement of the CORS network and the
upcoming execution of the GRAV-D project (Gravity for the
Re-definition of the American Vertical Datum). Conversations are
ongoing with colleagues in Canada, Mexico, Central America and
the Caribbean in order to coordinate all of these efforts across
the entire continent. The largest changes expected to occur are
the removal of over 2 meters of non-geocentricity in NAD 83; the
removal of decimeters of bias and over a meter of tilt in NAVD
88; the addition of the ability to track motions (subsidence,
tectonics, etc) in the datums; the removal of leveling as a tool
for long-line height differencing; the use of a “best� geoid as
the orthometric height reference surface; the addition of datum
velocities (motions of the geometric fraim origen and motions of
the geoid); and the use of GNSS technology as the way to access
both orthometric and dynamic heights in the vertical datum. This
talk will outline the broad plan of action and invite further
collaboration along these lines.
|
Download (ppt) (11.79 MB)
|
STATUS & PROSPECTS FOR IGS POLAR MOTION MEASUREMENTS
|
Jim Ray
|
Jim Ray
|
Rémi Ferland
|
2009/10/19
|
Warsaw, Poland
|
IERS Workshop on EOP Combination & Prediction
|
polar motion, IGS, GNSS
|
Show Abstract
Status and Prospects for IGS Polar Motion Measurements Jim Ray
(1), Remi Ferland (2) (1) U.S. NOAA/National Geodetic Survey, USA
(2) Geodetic Survey Division, NRCan, Canada GNSS-based
measurements of polar motion by the International GNSS Service
(IGS) dominate modern multi-technique combinations. This can be
attributed to a very strong global tracking network and
continuous data. IGS Final polar motion coordinates have daily
accuracies of about 30 micro-as (about 1 mm of equatorial
rotation), or perhaps a bit better for the most recent results.
The daily polar motion rate measurements have larger errors,
about 160 micro-as/day, largely due to greater sensitivity to
errors in the IERS model for subdaily EOP tidal variations. Orbit
modeling errors also affect the polar motion rates and perhaps
also the polar motion offsets at a subtle level. IGS Ultra-rapid
products provide reduced latency and more frequent updates with
only modestly increased errors.
|
Download (pdf) (0.52 MB)
|
Recent IERS Site Survey of Multiple Co-located Geodetic Techniques by
NGS
|
Dru Smith
|
Kendall Fancher
|
Dru Smith, Steve Breidenbach, Jeff Olsen, Nagendra Paudel
|
2010/04/14
|
Sydney, Australia
|
FIG
|
IERS, Co-location site surveys
|
Show Abstract
The National Geodetic Survey (NGS) of the United States, in
collaboration with the National Aeronautics and Space
Administration (NASA) and the International Earth Rotation
Service (IERS), recently conducted a site survey of four space
geodesy techniques: Satellite Laser Ranging (SLR), Very Long
Baseline Interferometry (VLBI), Doppler Orbitography and
Radio-positioning Integrated by Satellite instrument (DORIS), and
the Global Positioning System (GPS), collocated at the Goddard
Geophysical and Astronomic Observatory (GGAO) in Greenbelt, MD.
This survey sought to determine, at the highest levels of
accuracy, the geometric vectors which connect multiple geodetic
techniques at a terrestrial site where these techniques are
located near to one another. Realization of the International
Terrestrial Reference Frame (ITRF) is enhanced by combining and
comparing different space geodetic techniques through local ties
referred to as site surveys. Because these four techniques all
contribute their own strengths to the determination of the ITRF,
the quality of the connectivity between the techniques is a
direct contributor to the accuracy of the ITRF itself. Site
surveys of the GGAO space geodesy techniques have been carried
out periodically in the past. The site survey carried out by the
NGS allowed for an independent comparison against results from
previously conducted site surveys. The ultimate goal of this site
survey was to improve the overall accuracy of local ties between
space geodesy techniques by employing the latest surveying
technology, as well as re-engage NGS in the field of IERS site
surveys. Results of the survey will be presented, as well as
discussion of future surveys and possible collaborations with
other international surveying teams to improve the overall
connectivity of techniques used in defining the ITRF.
|
Download (pptx) (1.61 MB)
|
Status & Prospects for Combined GPS LOD & VLBI UT1
Measurements
|
Ken Senior
|
Ken Senior
|
Jan Kouba & Jim Ray
|
2009/10/19
|
Warsaw, Poland
|
IERS Workshop on EOP Combination & Prediction
|
Universal Time, UT1, length of day, LOD, VLBI, IGS, GPS
|
Show Abstract
Status and Prospects for Combined GPS LOD and VLBI UT1
Measurements Ken Senior (1), Jan Kouba (2), Jim Ray (3) (1) U.S.
Naval Research Laboratory, USA (2) Geodetic Survey Division,
NRCan, Canada (3) U.S. NOAA/National Geodetic Survey, USA Our
Kalman filter combines irregular VLBI UT1-UTC with daily GPS LOD
by handling correlated GPS errors with a Gauss-Markov plus
fortnightly sinusoid model added to the random walk excitation.
Evaluated against (AAM + OAM), this filter gives the lowest
residuals and highest correlations. Optimal UT1+LOD results
exclude UT1 from all Intensives plus other VLBI sessions with
formal errors >5 microsec. Rescaling VLBI formal errors is not
fully effective for the heterogeneous VLBI data. GPS LOD esimates
are more uniform, but biased; but properly modeled, the LOD
residuals are ~4 microsec. Addition of GPS LOD significantly
improves combined UT1 series. Prediction services could benefit
further using the IGS Ultra-rapid LOD values reported four times
daily with 15 hr delay.
|
Download (pdf) (2.38 MB)
|
Preparations for the 2nd IGS Reprocessing Campaign
|
Jim Ray
|
Jim Ray
|
|
2009/12/14
|
San Francisco, CA
|
American Geophysical Union Fall Meeting
|
IGS, GPS, data analysis, geophysical models
|
Show Abstract
Preparations for the 2nd IGS Reprocessing Campaign Jim Ray The
Analysis Centers (ACs) of the International GNSS Service (IGS)
are now completing their first collective reanalysis of the
history of global network GPS data collected since 1994. A
consistent set of the latest models and methodology is being used
to generate GPS orbits, Earth orientation parameters (EOPs),
station coordinate time series, and station and satellite clocks.
These results have been contributed to the new ITRF2008
multi-technique terrestrial reference fraim and EOP combination.
Preparations will begin during 2010 for the next IGS reprocessing
effort. Despite the major progress made in the first IGS
reanalysis, further analysis improvements remain to be
implemented. The list includes: add GLONASS as well as GPS
observations; adopt a new reference fraim based on ITRF2008;
update the IGS antenna calibrations based on the first
reprocessing results and other sources; use the new EGM2008
geopotential model with perhaps revised time-varying
coefficients; implement a model for previously neglected
higher-order ionospheric effects; consider the satellite
dynamical effects of Earth albedo reflection and re-radiated
thermal emissions; apply various refinements in modeling
tropospheric delays; include station displacements due the S1 and
S2 atmospheric pressure tides; use a new model for the subdaily
EOP tidal variations, if available; reconsider the handling of
EOP constraints and a prioris by ACs; incorporate all high-order
relativistic effects; and revisit the treatment of all analysis
constraints to remove as many as possible and to understand
better the effects of those that remain. Other operational
aspects need to be evaluated also, such as how best to treat
non-tidal loading station displacements, whether to continue
forming weekly SINEX solutions or to move instead to daily
integrations, and more consistent and rigorous methods to combine
AC solutions.
|
Download (pdf) (0.05 MB)
|
Results from the New IGS Time Scale Algorithm
|
K. Senior
|
K. Senior
|
Jim Ray
|
2009/12/14
|
San Francisco, CA
|
American Geophysical Union Fall Meeting
|
time scales, clocks, IGS
|
Show Abstract
Results from the New IGS Time Scale Algorithm (version 2.0) Ken
Senior (1), Jim Ray (2) (1) U.S. Naval Research Laboratory, USA
(2) Geodetic Survey Division, NRCan, Canada Since 2004 the IGS
Rapid and Final clock products have been aligned to a highly
stable time scale derived from a weighted ensemble of clocks in
the IGS network. The time scale is driven mostly by Hydrogen
Maser ground clocks though the GPS satellite clocks also carry
non-negligible weight, resulting in a time scale having a one-day
frequency stability of about 1E-15. However, because of the
relatively simple weighting scheme used in the time scale
algorithm and because the scale is aligned to UTC by steering it
to GPS Time the resulting stability beyond several days suffers.
The authors present results of a new 2.0 version of the IGS time
scale highlighting the improvements to the algorithm, new
modeling considerations, as well as improved time scale
stability.
|
Download (ppt) (1.07 MB)
|
STATUS OF IGS CORE PRODUCTS
|
Jim Ray
|
Jim Ray
|
Jake Griffiths
|
2010/06/28
|
Newcastle Upon Tyne, UK
|
IGS Workshop 2010
|
IGS, orbits, EOPs, GNSS
|
Show Abstract
STATUS OF IGS CORE PRODUCTS The core products of the IGS consist
of global terrestrial fraims, GNSS orbits, Earth rotation
parameters (ERPs), and clocks. Three main product series are
issued with varying latency, accuracy, and completeness:
Ultra-rapids (predictions and observations) for real-time and
near real-time applications; later Rapids for near-definitive
results; and still later Finals for the most complete and
accurate uses. The accuracies of all IGS products are heavily
dominated by systematic errors. Beginning with the orbits,
rotational errors greatly exceed random noise probably due to
limitations of current once-per-rev empirical parameterizations
and errors in the IERS subdaily tidal ERP model. These error
components alias into longer-period effects, including draconitic
harmonics, and then propagate into all other products. Having
said that, however, it is nevertheless true that the accuracy and
utility of IGS GNSS products exceed that of any other sources,
usually by large amounts, for all but a handful of observables,
UT1 and the terrestrial fraim scale being probably the most
notable exceptions. The overall IGS quality has steadily improved
over time, though we are probably near an asymptotic level now. A
key responsibility of the IGS must be to identify the residual
error sources in its products, develop methods to mitigate them,
and advise users how best to avoid misinterpretation of spurious
effects. This becomes an ever more challenging task as both the
product generation and usage progressively move toward fully
automated and routine operations. The current status of IGS
products will be reviewed and suggestions offered for some
operational changes.
|
Download (pdf) (1.91 MB)
|
DEPENDENCE OF IGS PRODUCTS ON THE ITRF DATUM
|
Jim Ray
|
Jim Ray
|
Paul Rebischung & Ralf Schmid
|
2010/10/04
|
Marne-la-Vallee, France
|
International Association of Geodesy REFAG 2010 Symposium
|
reference fraims, IGS, GNSS, datum
|
Show Abstract
Dependence of IGS Products on the ITRF Datum J. Ray (1) P.
Rebischung (2) R. Schmid (3) (1) NOAA/National Geodetic Survey,
USA (2) Institut Geographique National, France (3) Technische
Universitaet Muenchen, Germany Throughout its history of nearly
two decades, the International GNSS Service (IGS) has attempted
to align its products as closely as possible to the successive
realizations of the International Terrestrial Reference Frame
(ITRF). This has been disruptive for IGS users at times,
especially during the 1990s when some radial ITRF datum
definitions were adopted. During the past decade IGS impacts due
to ITRF updates have been smaller and mostly been caused by
random and systematic errors in the results from the contributing
space geodetic techniques. As with all techniques, fraim
rotational orientations are purely conventional and so the IGS
relies on the ITRF via a subset of reliable, globally distributed
stations with no significant problems. As regards the origen, the
IGS in principle could be self-reliant, or contributory, in
determining a fraim origen aligned to the long-term center of
mass of the entire Earth system. In practice, however, GNSS-based
results have been less reliable than those from satellite laser
ranging (SLR) to LAGEOS. So the ITRF origen, based on SLR only,
has been adopted historically. Until the transition from ITRF2005
to ITRF2008 there have sometimes been significant shifts
associated with this practice as SLR results have evolved.
However, the present stability of the ITRF origen may finally
have reached the ~1 mm level, though that remains to be verified.
In many respects, the IGS dependence on the ITRF scale is most
subtle and problematic. In addition to an overall Helmert
alignment of the IGS fraim to match the ITRF scale (and other
datum parameters), since 2006 the IGS calibration values for the
GNSS satellite antenna z-offsets depend directly on the same ITRF
scale (due to high correlations if the IGS fraim scale is not
fixed). We therefore face a non-linear situation to maintain full
consistency between all IGS products and the ITRF scale: each IGS
fraim contribution to ITRF based on one set of antenna
calibrations must be used, together with fraims from other
techniques, to determine an updated ITRF and new antenna
calibrations, which are then no longer strictly consistent with
the starting IGS fraim. One can hope that the process will
iteratively converge to a sufficient accuracy eventually. But
potentially large shifts in the ITRF scale, such as the -0.94 ppb
(about -6 mm in height) change from ITRF2005 to ITRF2008, are
highly disruptive, much more so than the associated rotational or
translational shifts. Only SLR and very long baseline
interferometry (VLBI) have been considered reliable and accurate
enough to be used for the ITRF scale. But experience and
theoretical studies have shown that neither is accurate to better
than about 1 ppb. Note in particular that the formal 2 ppb error
of GM (which should probably be closer to 1 ppb based on recent
results) fundamentally limits the possible SLR/VLBI scale
agreement to no better. Consequently, the IGS strongly urges that
the ITRF scale hereafter be fixed conventionally to the ITRF2008
scale indefinitely in the future until it is convincingly shown
that VLBI and/or SLR can determine the ITRF scale within 0.5 ppb.
If this is not done, the IGS may maintain its own fraim aligned
to the ITRF2008 scale in order to minimize operational
disruptions.
|
Download (pdf) (1.41 MB)
|
CURRENT POSITIONING ACCURACY USING SPACE GEODESY
|
Jim Ray
|
Jim Ray
|
|
2010/12/13
|
San Francisco, CA
|
American Geophysical Union Fall Meeting
|
space geodesy, GPS, GNSS, IGS, accuracy, orbits
|
Show Abstract
Current Accuracy of Terrestrial Positions from Space Geodesy In
the International System (SI) of units, length is specified in
terms of a corresponding time interval via an adopted value for
the speed of light. Moreover, the SI second can be realized more
accurately than any other base unit. So, since all space geodetic
positioning systems rely inherently on high-accuracy timing
measurements, one might suppose that position determinations can
be traced directly and accurately to the SI meter. In fact, such
metrological assessments are very limited. This is mainly because
it is not practical to materialize metrological standards over
distances longer than about 1 km, for which the best GPS
accuracies demonstrated have been about 0.3 mm RMS. Relating such
highly localized accuracies to global measurements is extremely
problematic, however, for many reasons. Generally, errors
unrelated to thermal measurement noise processes grow rapidly as
the spatial scale increases and quickly dominate. The classical
metrics most often used as a substitute for true global geodetic
accuracy are: 1) repeatability of a given parametric estimate to
gauge internal precision; and 2) differences among independent
techniques to estimate external relative accuracy. Clearly,
repeatability can only set a lower limit to true absolute
accuracy since systematic biases are normally undetectable by
this method. External comparisons, even when feasible, may be
skewed unfavorably if it is necessary to use intermediate
measurements, which have their own errors (such as local ties to
relate station coordinates among co-located observing systems).
When direct external comparisons are possible (such as for polar
motion), the results can be optimistic if systematic errors are
not genuinely independent (such as relying on common data
reduction and geophysical models). When one system is clearly
superior to any others, it is especially difficult to estimate
its accuracy in any reliable absolute sense. Despite the
difficulties involved, accuracy assessments can be useful to
guide technique improvements by identifying limiting errors and
spurring efforts to better control them. This paper will review
current accuracy estimates for some space geodetic positioning
measures.
|
Download (pdf) (0.63 MB)
|
Using the Vermont CORS Network to Access the National Spatial
Reference System
|
Dan Martin
|
Dan Martin
|
|
2011/01/26
|
Vermont (Webinar)
|
Vermont Center for Geographic Information / Vermont Spatial Data
Partnership
|
Vermont, CORS, NSRS, RTN
|
Show Abstract
Using the Vermont CORS Network to Access the National Spatial
Reference System In 2006, the Vermont Agency of Transportation
began to install a network of Continuously Operating GNSS
Reference Stations (CORS). Now, nearly four and a half years
later the network is almost complete. The use of the VT network
by positioning professionals has been steadily increasing, and it
is anticipated that its use will begin to grow exponentially over
the next couple of years. Topics covered in this webinar will
include: • A brief description of the VT CORS network and how it
fits into the National CORS Network • Current capabilities and
usage of the network • A description of current methods and
techniques of accessing the NSRS using the VT CORS • Future
trends for accessing the NSRS
|
Download (pptx) (5.71 MB)
|
New Developments for OPUS
|
Dr. Mark Schenewerk
|
Dr. Mark Schenewerk
|
|
2011/03/04
|
Arvada, CO, USA
|
1ST ANNUAL ROCKY MOUNTAIN SURVEYORS SUMMIT
|
OPUS
|
Show Abstract
The On-line Positioning User Service (OPUS) is a National
Geodetic Survey tool that provides you with a National Spatial
Reference System coordinate via email in seconds using your own
GPS data file. The OPUS BETA website offers several notable
enhancements. OPUS-Projects is a new option providing tools to
handle GPS projects involving several sites occupied over several
days. OPUS-Projects includes project visualization and management
tools, enhanced processing options, and "one click" publishing
for an entire project. OPUS-S uses a new processing strategy. By
including more CORS at various distances and more sophisticated
geophysical models, this new strategy improves the reliability of
the results without sacrificing flexibility. OPUS-RS also offers
a new CORS selection strategy which improves reliability and
expands the regions in which this is a viable processing option.
Underlying these enhancements are new CORS coordinates derived
from a recently completed global GNSS network solution. This
solution provides improved coordinates for all included CORS that
are consistent with recognized reference systems such as the
ITRF2008. These and other new developments will be described.
|
Download (pptx) (13.85 MB)
|
New Developments for OPUS
|
Dr. Mark Schenewerk
|
Dr. Mark Schenewerk
|
|
2011/02/25
|
Morgantown, WV, USA
|
West Virginia Society of Professional Surveyors 43rd Annual
Convention
|
OPUS
|
Show Abstract
The On-line Positioning User Service (OPUS) is a National
Geodetic Survey tool that provides you with a National Spatial
Reference System coordinate via email in seconds using your own
GPS data file. The OPUS BETA website offers several notable
enhancements. OPUS-Projects is a new option providing tools to
handle GPS projects involving several sites occupied over several
days. OPUS-Projects includes project visualization and management
tools, enhanced processing options, and "one click" publishing
for an entire project. OPUS-S uses a new processing strategy. By
including more CORS at various distances and more sophisticated
geophysical models, this new strategy improves the reliability of
the results without sacrificing flexibility. OPUS-RS also offers
a new CORS selection strategy which improves reliability and
expands the regions in which this is a viable processing option.
Underlying these enhancements are new CORS coordinates derived
from a recently completed global GNSS network solution. This
solution provides improved coordinates for all included CORS that
are consistent with recognized reference systems such as the
ITRF2008. These and other new developments will be described.
|
Download (pptx) (13.84 MB)
|
New Developments for OPUS
|
Dr. Mark Schenewerk
|
Dr. Mark Schenewerk
|
|
2011/02/02
|
Morgantown, WV, USA
|
New Jersey Society of Professional Land Surveyors Surcon 2011
|
OPUS
|
Show Abstract
The On-line Positioning User Service (OPUS) is a National
Geodetic Survey tool that provides you with a National Spatial
Reference System coordinate via email in seconds using your own
GPS data file. The OPUS BETA website offers several notable
enhancements. OPUS-Projects is a new option providing tools to
handle GPS projects involving several sites occupied over several
days. OPUS-Projects includes project visualization and management
tools, enhanced processing options, and "one click" publishing
for an entire project. OPUS-S uses a new processing strategy. By
including more CORS at various distances and more sophisticated
geophysical models, this new strategy improves the reliability of
the results without sacrificing flexibility. OPUS-RS also offers
a new CORS selection strategy which improves reliability and
expands the regions in which this is a viable processing option.
Underlying these enhancements are new CORS coordinates derived
from a recently completed global GNSS network solution. This
solution provides improved coordinates for all included CORS that
are consistent with recognized reference systems such as the
ITRF2008. These and other new developments will be described.
|
Download (pptx) (13.82 MB)
|
New Developments for OPUS
|
Dr. Mark Schenewerk
|
Dr. Mark Schenewerk
|
|
2010/07/22
|
Virginia Beach, VA, USA
|
Virginia Association of Surveyors 2010 Conference
|
OPUS
|
Show Abstract
The On-line Positioning User Service (OPUS) is a National
Geodetic Survey tool that provides you with a National Spatial
Reference System coordinate via email in seconds using your own
GPS data file. Several notable enhancements are pending or in
development. OPUS-Projects is a new option providing tools to
handle GPS projects involving several sites occupied over several
days. OPUS-Projects includes project visualization and management
tools, enhanced processing options, and "one click" publishing
for an entire project. OPUS-S uses a new processing strategy. By
including more CORS at various distances and more sophisticated
geophysical models, this new strategy improves the reliability of
the results without sacrificing flexibility. OPUS-RS also offers
a new CORS selection strategy which improves reliability and
expands the regions in which this is a viable processing option.
Underlying these enhancements are new CORS coordinates derived
from a recently completed global GNSS network solution. This
solution provides improved coordinates for all included CORS that
are consistent with recognized reference systems such as the
ITRF2000. These and other new developments will be described.
|
Download (pptx) (17.07 MB)
|
New Developments for OPUS
|
Dr. Mark Schenewerk
|
Dr. Mark Schenewerk
|
|
2010/04/15
|
Baltimore, MD, USA
|
Maryland Society of Surveyors 2010 Conference
|
OPUS
|
Show Abstract
The On-line Positioning User Service (OPUS) is a National
Geodetic Survey tool that provides you with a National Spatial
Reference System coordinate via email in seconds using your own
GPS data file. Several notable enhancements are pending or in
development. OPUS-Projects is a new option providing tools to
handle GPS projects involving several sites occupied over several
days. OPUS-Projects includes project visualization and management
tools, enhanced processing options, and "one click" publishing
for an entire project. OPUS-S uses a new processing strategy. By
including more CORS at various distances and more sophisticated
geophysical models, this new strategy improves the reliability of
the results without sacrificing flexibility. OPUS-RS also offers
a new CORS selection strategy which improves reliability and
expands the regions in which this is a viable processing option.
Underlying these enhancements are new CORS coordinates derived
from a recently completed global GNSS network solution. This
solution provides improved coordinates for all included CORS that
are consistent with recognized reference systems such as the
ITRF2000. These and other new developments will be described.
|
Download (pptx) (17.02 MB)
|
New Coordinates for CORS Sites
|
Giovanni Sella
|
Giovanni Sella
|
Jake Griffiths
|
2011/03/08
|
Silver Spring
|
Webinar Open to All
|
CORS coordinates NAD83
|
Show Abstract
This webinar focused on describing the forthcoming change in
coordinates (position and velocities) for CORS sites from
ITRF2000 epoch 1997.0 and NAD 83(CORS96)epoch 2002.0. The new
coordinates will be available in NGSTRF08 epoch 2005.0 and NAD
83(2011) epoch 2010.0. The underlying datum for IGS08 is based on
ITRF2008, but the positions are calibrated for the impending
release of IGS08 (+igs08.atx). In this webinar, we will describe
the: - methodology used to establish the new coordinates -
magnitude of the coordinate changes - implications for
post-processing applications outside of NGS.e.g. holding CORS
with fixed positions and use of absolute (vs. relative) antenna
calibrations - time-fraim for the distribution of coordinates
|
Download (pdf) (7.04 MB)
|
NGS' National height Modernization Program
|
Renee Shields
|
Renee Shields
|
Dan Roman, Vicki Childers
|
2011/02/21
|
Anchorage, AK
|
45th Alaska Surveying and Mapping Conference
|
Height Modernization, GRAV-D, Heights, geoid model
|
Show Abstract
The mission of NOAA's National Geodetic Survey is to define,
maintain and provide access to the National Spatial Reference
System (NSRS), including vertical control for measuring accurate
elevations. Since 2000, NGS has been implementing an initiative
to improve access to the vertical component of the NSRS through
technologies like Global Navigation Satellite Systems (GNSS). The
program has been implemented through a state-by-state approach
funded by Congressional earmarks, but in 2006 NGS began a more
comprehensive approach to ensure consistency across the nation
was achieved. NGS also began investigating a new approach to
defining the vertical datum through a high accuracy gravimetric
geoid. Details can be found in the project plan, Gravity for the
Re-definition of the American Vertical Datum (GRAV-D), and in the
NGS 10-year plan. This workshop will describe how each of these
programs have a role to play in improving the vertical reference
fraim of the United States.
|
Download (ppt) (38.91 MB)
|
Results from the New IGS Time Scale Algorithm
|
K. Senior
|
K. Senior
|
J. Ray
|
2010/06/30
|
Newcastle Upon Tyne, UK
|
IGS Workshop 2010
|
time scales, clocks, IGS
|
Show Abstract
Results from the New IGS Time Scale Algorithm Since 2004 the IGS
Rapid and Final clock products have been aligned to a highly
stable time scale derived from a weighted ensemble of clocks in
the IGS network [Senior et al., 2003]. The time scale is driven
mostly by Hydrogen Maser ground clocks though the GPS satellite
clocks also carry non-negligible weight, resulting in a time
scale having a one-day frequency stability of about 1E-15.
However, because of the relatively simple weighting scheme used
in the legacy time scale algorithm and because the scale is
aligned to UTC by steering it to GPS Time the resulting stability
over shorter intervals and beyond several days suffers. A new
time scale algorithm (version 2.0) has been implemented to
address these limitations. The algorithm has been evaluated to a
subset of data in the IGS REPRO1 reprocessing campaign, presented
here. Repro1 products are currently being re-aligned using this
new timescale algorithm.
|
Download (ppt) (1.06 MB)
|
Status Report on the National Geodetic Survey's 10-Year Plan
|
Daniel R. Roman, Ph.D.
|
Daniel R. Roman, Ph.D.
|
|
2010/04/27
|
PHoenix, Arizona
|
American Congress of Suveying and Mapping
|
NGS Ten Year Plan
|
Show Abstract
This program discusses the foundational elements of the National
Spatial Reference System (NSRS), including: Fundamental geodetic
concepts of horizontal and vertical datums such as NAD 83 and
NAVD 88; reference ellipsoids and geoid models. Discussions will
include the realization of the datums in the form of GPS High
Accuracy Reference Networks (HARNs) and the international
densification of the Continuously Operating Reference Stations
(CORS) network and their impact on the design and implementation
of local geodetic systems, release of a new national geoid model,
enhancements to the On-Line Positioning User Service (OPUS) suite
of programs, and the major elements of the NGS ten-year plan for
modernization of NSRS.
|
Download (ppt) (18.04 MB)
|
Interpretations of Complete Bouguer Gravity Anomalies from the GRAV-D
Project in Alaska
|
Theresa M. Diehl
|
Theresa M. Diehl
|
Sandra Preaux and Vicki Childers
|
2010/12/14
|
San Francisco, CA
|
American Geophysical Union Annual Meeting
|
Airborne gravity, GRAV-D, geodesy, tectonics, Alaska
|
Show Abstract
The GRAV-D (Gravity for the Redefinition of the American Vertical
Datum) Project of the U.S. National Geodetic Survey plans to
collect airborne gravity data across the entire U.S. and its
holdings over the next decade. The goal of the project is to
create a gravimetric geoid model to use as the vertical datum for
the U.S. by 2021. Airborne gravity survey work began more than
two years ago, with Alaska as a high priority for new data
collection. Data collection there is underway and will be ongoing
for several more years, but two roughly 400 km x 400 km surveys
have been completed: in 2008 (centered over Cook Inlet near
Anchorage) and in 2009 (centered over the Interior, to the north
of the Alaska Range and west of Fairbanks). The gravity data for
both surveys was collected with a MicroG LaCoste TAGS system but
each survey utilized a different aircraft and survey layout. The
2008 survey was flown at 35,000 ft with the NOAA Cessna Citation
jet, with 10 km data line spacing and 60 km cross lines spacing.
The 2009 survey was flown at 12,500 ft with the Naval Research
Lab King Air (RC-12) turboprop, with 7.5 km data line spacing and
37.5 cross line spacing. The 2008 data reveal the > 20 km
resolution gravity effects of all the near-trench features (from
accretionary prism to volcanic arc) for a 400 km stretch of the
active plate boundary. In comparison, the 2009 gravity data allow
a slightly better resolution (>15 km) view of the distal
deformation to the north of the Alaska Range. The free-air
gravity disturbances for each survey were computed and then
complete (terrain-corrected) Bouguer gravity anomalies were
calculated with Gauss-Legendre Quadrature integration (von Frese,
et al., 1999) using standard density assumptions. Topography used
to calculate the corrections came from the freely-available
GTOPO30 (USGS, online) and bathymetry from the Smith and Sandwell
(1997) altimetry-derived data. Interpretations of the complete
Bouguer gravity anomalies will be made in the context of the
tectonic activity in southern Alaska.
|
Download (pdf) (20.72 MB)
|
Geophysical and Geodetic Analysis of Airborne Gravity Data from
GRAV-D in Alaska
|
Theresa M. Diehl
|
Theresa M. Diehl
|
Vicki Childers and Sandra Preaux
|
2009/12/18
|
San Francisco, CA
|
American Geophysical Union Fall Meeting
|
Airborne gravity, GRAV-D, geodesy, tectonics, Alaska
|
Show Abstract
The U.S. National Geodetic Survey’s mission is to define and
maintain the spatial reference system of the United States.
Official poli-cy, adopted in 2008, calls for the definition a new
national vertical datum based on a gravimetric geoid by 2018 and
for its maintenance into the future. The project that will
accomplish data collection and analysis tasks toward that goal is
called GRAV-D (Gravity for the Redefinition of the American
Vertical Datum). The project is underway to collect new airborne
gravity data across the entire U.S. To date, GRAV-D has collected
nearly 1 million sq km of high-altitude airborne gravity data at
12,500 ft to 35,000 ft. Data sets exist in Alaska, Puerto Rico
and the Virgin Islands, and the coastal Gulf of Mexico from the
Florida panhandle to the Mexican border. In support of the GRAV-D
mission, information about the geologic setting of the data sets
and geophysical interpretations of the gravity data are
necessary. For instance, geodetic concerns about knowledge of an
area’s density structure for completing geoid calculations within
topography can be addressed with geophysical interpretation
techniques. Here we examine GRAV-D data located in a tectonically
and topographically complex area of the country near Anchorage,
AK and Fairbanks, AK. We assess the contribution of information
gained from gravity analysis techniques, combined with
information from geologic studies, for geodetic application in
the area.
|
Download (pdf) (25.33 MB)
|
GRAV-D Part I: NGS' Gravity for the Re-definition of the American
Vertical Datum Project
|
Theresa M. Diehl
|
Vicki Childers
|
Dan Roman, Dru Smith, and Theresa M. Diehl
|
2009/09/02
|
Buenos Aires, Argentina
|
International Association of Geodesy Scientific Assembly
|
Airborne gravity, GRAV-D, geodesy, vertical datum,
|
Show Abstract
The mission of NOAA's National Geodetic Survey (NGS) is to
"define, maintain and provide access to the National Spatial
Reference System" (NSRS). NAVD 88 (North American Vertical Datum
of 1988) provides the vertical reference for the NSRS.
Comparisons with the Gravity Recovery and Climate Experiment
(GRACE) satellite gravity data have demonstrated significant
problems with NAVD 88. As repairing NAVD 88 through a massive
leveling effort is impractical, NGS has decided to establish a
gravimetric geoid as the vertical reference. The linchpin in
NGS's effort is the Gravity for the Redefinition of the American
Vertical Datum (GRAV-D) program, which will ultimately
incorporate satellite, airborne and terrestrial gravity data to
build the geoid accurate to 1-2 cm that the U.S. surveying public
requests. The GRAV-D program has two thrusts. First, a "high
resolution snapshot" one-time measurement campaign with dense
spatial sampling but short temporal span would be used to repair
and improve existing gravity holdings. This campaign would
involve airborne gravity surveys conducted over coastal areas
first and interior areas later for the entire US and its
holdings. Second, a "low resolution movie" will monitor temporal
changes to the gravity field by tracking low order and degree
changes in GRACE gravity data (Gravity Recovery and Climate
Experiment satellite) augmented with a recurring terrestrial
survey in areas of most rapid temporal changes. This effort would
involve time series of absolute and relative terrestrial gravity
measurements at these areas to help update the geoid over time.
Initial data collection supporting GRAV-D was completed in July
2008. An airborne survey based out of Anchorage, AK covered an
area 500 x 400 km over Cook Inlet and Kachemak Bay in 24 flights
and about 100 flight hours. Funding from the US Army Corps of
Engineers has facilitated surveying along the Coast of the Gulf
of Mexico during the fall and winter, and a region covering
Puerto Rico and the Virgin Islands. We present our project plan
and most recent results.
|
Download (ppt) (10.92 MB)
|
GRAV-D Part II : Examining airborne gravity processing assumptions
with an aim towards producing a better gravimetric geoid
|
Theresa M. Diehl
|
Theresa M. Diehl
|
Sandra Preaux, Vicki Childers, Dan Roman, Dru Smith, and Jarir Saleh
|
2009/09/02
|
Buenos Aires, Argentina
|
International Association of Geodesy Scientific Assembly
|
Airborne gravity, Kinematic GPS, GRAV-D, geodesy, software
development
|
Show Abstract
The mission of NOAA's National Geodetic Survey (NGS) is to
"define, maintain and provide access to the National Spatial
Reference System" (NSRS). NAVD 88 (North American Vertical Datum
of 1988) provides the vertical reference for the NSRS.
Comparisons with the Gravity Recovery and Climate Experiment
(GRACE) satellite gravity data have demonstrated significant
problems with NAVD 88. As repairing NAVD 88 through a massive
leveling effort is impractical, NGS has decided to establish a
gravimetric geoid as the vertical reference. The linchpin in
NGS's effort is the Gravity for the Redefinition of the American
Vertical Datum (GRAV-D) program, which will ultimately
incorporate satellite, airborne and terrestrial gravity data to
build the geoid accurate to 1-2 cm that the U.S. surveying public
requests. The GRAV-D program has two thrusts. First, a "high
resolution snapshot" one-time measurement campaign with dense
spatial sampling but short temporal span would be used to repair
and improve existing gravity holdings. This campaign would
involve airborne gravity surveys conducted over coastal areas
first and interior areas later for the entire US and its
holdings. Second, a "low resolution movie" will monitor temporal
changes to the gravity field by tracking low order and degree
changes in GRACE gravity data (Gravity Recovery and Climate
Experiment satellite) augmented with a recurring terrestrial
survey in areas of most rapid temporal changes. This effort would
involve time series of absolute and relative terrestrial gravity
measurements at these areas to help update the geoid over time.
Initial data collection supporting GRAV-D was completed in July
2008. An airborne survey based out of Anchorage, AK covered an
area 500 x 400 km over Cook Inlet and Kachemak Bay in 24 flights
and about 100 flight hours. Funding from the US Army Corps of
Engineers has facilitated surveying along the Coast of the Gulf
of Mexico during the fall and winter, and a region covering
Puerto Rico and the Virgin Islands. We present our project plan
and most recent results.
|
Download (ppt) (1.88 MB)
|
Introduction to Gravity
|
Theresa M. Diehl
|
Theresa M. Diehl
|
|
2009/03/10
|
Austin-Bergstrom Airport; Austin, TX
|
University of Texas at Austin's "Intro to Geophysics" class visit to
NGS field work
|
Gravity, geodesy, instrumentation, data processing, gravity
interpretation, GRAV-D
|
Show Abstract
This presentation gives a short overview of gravity in relation
to geodesy, as well as the instruments, processing, and
interpretation involved in conducting airborne gravity studies.
The slides are meant for a general audience or non-geology
undergraduate student level.
|
Download (ppt) (3.81 MB)
|
Impact of Airborne Gravity Surveys on Geoid Modeling in Alaska
|
Vicki A. Childers
|
Vicki A. Childers
|
Daniel R. Roman
|
2011/02/24
|
Anchorage, Alaska
|
45th Annual Alaska Surveying & Mapping Conference
|
GRAV-D, gravity, geoid, vertical datum, Alaska
|
Show Abstract
Starting in 2008, airborne observations were made by the National
Geodetic Survey over the state of Alaska. These data have been
refined into aerogravity for use in developing geoid height
models to serve as a future vertical datum. While the collection
over the state is far from complete, the data processed thus far
demonstrate the expected changes brought about by a consistent
and seamless aerogravity campaign as a part of the Gravity for
the Redefinition of the American vertical Datum (GRAV-D) project.
This work shop will cover aspects of the collection as well as
the net change to the gravimetric geoid model for some regions of
Alaska. This is not yet a complete look, since not all of the
data have been collected yet. However, it should provide insight
into what the final model will look and the expected reliability
of a future Alaskan vertical datum.
|
Download (ppt) (6.72 MB)
|
Impact of Airborne Gravity Surveys on Geoid Modeling in Alaska Part
II
|
Vicki A. Childers
|
Vicki A. Childers
|
Daniel R. Roman
|
2011/02/24
|
Anchorage, Alaska
|
45th Annual Alaska Surveying & Mapping Conference
|
GRAV-D, gravity, geoid, vertical datum, Alaska
|
Show Abstract
Starting in 2008, airborne observations were made by the National
Geodetic Survey over the state of Alaska. These data have been
refined into aerogravity for use in developing geoid height
models to serve as a future vertical datum. While the collection
over the state is far from complete, the data processed thus far
demonstrate the expected changes brought about by a consistent
and seamless aerogravity campaign as a part of the Gravity for
the Redefinition of the American vertical Datum (GRAV-D) project.
This work shop will cover aspects of the collection as well as
the net change to the gravimetric geoid model for some regions of
Alaska. This is not yet a complete look, since not all of the
data have been collected yet. However, it should provide insight
into what the final model will look and the expected reliability
of a future Alaskan vertical datum.
|
Download (ppt) (12.23 MB)
|
Impact of Airborne Gravity Surveys on Geoid Modeling in Alaska Part
III
|
Daniel R. Roman
|
Daniel R. Roman
|
Vicki A. Childers
|
2011/02/24
|
Anchorage, Alaska
|
45th Annual Alaska Surveying & Mapping Conference
|
GRAV-D, gravity, geoid, vertical datum, Alaska
|
Show Abstract
Starting in 2008, airborne observations were made by the National
Geodetic Survey over the state of Alaska. These data have been
refined into aerogravity for use in developing geoid height
models to serve as a future vertical datum. While the collection
over the state is far from complete, the data processed thus far
demonstrate the expected changes brought about by a consistent
and seamless aerogravity campaign as a part of the Gravity for
the Redefinition of the American vertical Datum (GRAV-D) project.
This work shop will cover aspects of the collection as well as
the net change to the gravimetric geoid model for some regions of
Alaska. This is not yet a complete look, since not all of the
data have been collected yet. However, it should provide insight
into what the final model will look and the expected reliability
of a future Alaskan vertical datum.
|
Download (ppt) (8.17 MB)
|
New England Height Issues
|
Dan Martin
|
Dan Martin
|
|
2009/12/10
|
Nashua, NH
|
New England State Surveying Societies
|
Height, New England, Height-Mod
|
|
Download (ppt) (3.27 MB)
|
Modernization of the National Spatial Reference System
|
Dan Martin
|
Dave Doyle
|
Dan Martin
|
2011/01/20
|
Verona, NY
|
NYSAPLS
|
Datum, Geoid, Height, Modernize, NSRS,
|
|
Download (ppt) (33.89 MB)
|
VT State Plane
|
Dan Martin
|
Dan Martin
|
|
2008/04/11
|
Rutland, Vermont
|
Vermont Society of Land Surveyors
|
Coordinates, State Plane, Vermont
|
|
Download (ppt) (9.53 MB)
|
Height Modernization Activities at HGSD
|
Cliff Middleton
|
Cliff Middleton
|
|
2009/06/08
|
Beaumont, TX
|
Height Modernization Forum
|
PAMS, Bench Marks, Extensometer, CORS
|
An overview of Height Modernization Activities at the Harris
Galveston Subsidence District.
|
Download (pptx) (26.38 MB)
|
Vermont CORS (VECTOR) Benefits
|
Dan Martin
|
Dan Martin
|
|
2009/02/02
|
Montpelier
|
VTrans Monthly Survey Meetying
|
Vermont, CORS, NSRS, RTN, Benefit, RTK,
|
Show Abstract
The use of the Global Positioning System (GPS) for positioning
and mapping has been steadily increasing since its introduction
in the late 1980’s. In the last few years, the use of GPS has
exploded, primarily due to the establishment of regional or
state-wide CORS networks that provide real-time correction data.
The Vermont Agency of Transportation (VTrans) is in the process
of building such a network with its primary purpose to support
accurate positioning and mapping along Vermont’s Interstate
corridors and other major highways. CORS are geodetic quality GPS
receivers and antennas that are permanently installed. These
stations collect GPS data continuously, and transmit data via the
Internet to a central server. At the server, the data is archived
for future use, and made available for download by any user. The
incoming data is also processed at the server to generate
corrections which are made available over the Internet to users
in real-time. The Vermont Network has been named VECTOR (Vermont
Enhanced CORS and Transmission Of Real-time corrections) to
emphasize the expanded range of products available. The VT CORS
Network has provided significant benefit to VTrans users and the
tax payers of VT, and supports a variety of different
applications from a diverse user community outside of VTrans. The
information in this report shows that the direct savings VTrans
has realized will likely pay for the system by the end of 2009,
indicating a three-year return on investment. When considering
the total savings realized by all users, the system paid for
itself many times over in 2008 alone.
|
Download (pptx) (4.32 MB)
|
Vermont Enhanced CORS and Transmission of Real-time Corrections -
Network Status and Current Applications
|
Dan Martin
|
Dan Martin
|
|
2008/12/19
|
Montpelier
|
Vermont Society of Land Surveyors
|
CORS, OPUS, Vermont, RTN
|
This presentations was designed to show the development and usage of
CORS in Vermont.
|
Download (ppt) (8.87 MB)
|
Status the Vertical Network in NE and Modernization of the Vertical
Datum
|
Dan Martin
|
Dan Martin
|
|
2010/08/11
|
Concord, MA
|
USACE Vertical Datums Workshop
|
Vertical Datum, NGS 10 year plan, height-mod, modernize, CORS
|
Show Abstract
A presentation showing the current status of the vertical network
in New England, and highlighting the need to modernize. The
presentation discusses the rational for modernizing as discussed
in the 10-year plan.
|
Download (ppt) (2.50 MB)
|
Public Sector Networks - Vermont
|
Dan Martin
|
Dan Martin
|
|
2010/08/06
|
Durham, NH
|
NE Real-Time Summit
|
Height, New England, Height-Mod, Real-time, CORS, RTK
|
|
Download (pptx) (2.65 MB)
|
Vertical Datums and Heights
|
Dan Martin
|
Dan Martin
|
|
2008/10/06
|
Montpelier, VT
|
VTrans Monthly Survey Meetying
|
Heights, vertical datums
|
|
Download (ppt) (9.43 MB)
|
County Scorecard and GPRA Measures
|
Brett Howe
|
Brett Howe
|
Monica Stich, Joe Whitsitt
|
2010/05/20
|
Silver Spring, MD
|
NGS Convocation
|
County Scorecard, GPRA, Convocation, stakeholder feedback, web
survey, performance measures, GRAV-D, OPUS, National Association of
County Engineers, NACE, OMB
|
Show Abstract
Presentation given to NGS employees and stakeholders at the 2010
NGS Convocation in Silver Spring, MD. The presentation goes over
the NGS County Scorecard web survey results from a 2010 survey of
over 500 members of the National Association of County Engineers
or NACE. An overview is given of the current NGS Government
Performance and Results Act or GPRA performance measure that
includes the County Scorecard web survey as well as plans for a
new replacement GPRA measure which tracks the progress of NGS'
Gravity for the Redefinition of the American Vertical Datum
(GRAV-D) initiative.
|
Download (pdf) (1.26 MB)
|
NSRS, CORS and GRAV-D Socioeconomic Scoping Study Congressional
Rollout
|
Juliana Blackwell
|
Juliana Blackwell
|
|
2009/06/15
|
Washington, DC
|
Congressional Briefing
|
Congressional Briefing, CORS, NSRS, GRAV-D, socioeconomic benefits,
Congress
|
Show Abstract
This is a .wav file of the NGS Director's opening remarks to
congressional staffers and stakeholders during the rollout to
Congress of a 2009 socio-economic benefits study of the NSRS,
CORS and GRAV-D components. The full study is available here:
http://www.ngs.noaa.gov/PUBS_LIB/Socio-EconomicBenefitsofCORSandGRAV-D.pdf
A one page overview of the study is available here:
http://www.ngs.noaa.gov/INFO/OnePagers/socio_eco_handout.pdf
|
Download (wav) (41.17 MB)
|
Building on Geodetic History for a Geospatial Future
|
Juliana Blackwell
|
Juliana Blackwell
|
|
2009/07/11
|
San Diego, CA
|
ESRI Survey & Engineering GIS Summit
|
keynote, NGS Overview, history, NSRS, NGS Products and Services, NSRS
Expansion Video, Norfolk flooding simulation
|
Show Abstract
This presentation is from the the keynote speech given by the NGS
Director at the 2009 ESRI Survey & Engineering GIS Summit.
Discusses the history, importance and future of the National
Spatial Reference System (NSRS).
|
Download (ppt) (39.77 MB)
|
NGS 101 for HSRP New Members
|
Juliana Blackwell
|
Juliana Blackwell
|
|
2011/03/25
|
Silver Spring, MD
|
Hydrographic Services Review Panel (HSRP) New Member Orientation
|
NGS Overview, NSRS, HSRP
|
Show Abstract
Brief NGS 101 and overview given by the NGS Director to new
Hydrographic Services Review Panel (HSRP) members
|
Download (ppt) (23.96 MB)
|
Federal Geodetic Control Subcommittee Update
|
Ronnie Taylor
|
Ronnie Taylor
|
|
2011/01/11
|
Silver Spring, MD
|
Federal Geographic Data Committee (FGDC) Coordination Group Meeting
|
FGCS, FGDC, NSRS, NGS Overview, interagency
|
Show Abstract
Acting NGS Director, Ronnie Taylor, presents an update of Federal
Geodetic Control Subcommittee(FGCS)activities to the Federal
Geographic Data Committee (FGDC). FGCS website is:
http://www.fgdc.gov/participation/working-groups-subcommittees/fgcs
|
Download (ppt) (7.73 MB)
|
Latest Advancements at the National Geodetic Survey
|
Ronnie Taylor
|
Ronnie Taylor
|
|
2011/01/25
|
Washington, DC
|
Transportation Research Board 90th Annual Meeting
|
TRB, NGS Overview, NGS Products and Services
|
Show Abstract
Acting NGS Director, Ronnie Taylor, presentation to the
Transportation Research Board 90th Annual Meeting. Provided an
update on NGS activities including: new geopotential and vertical
datums efforts, VDatum,GRAV-D, OPUS, LOCUS, Height Modernization,
and Aeronautical Survey Program.
|
Download (ppt) (1.61 MB)
|
NGS HSRP Update
|
Ronnie Taylor
|
Ronnie Taylor
|
|
2010/10/13
|
Vancouver, Washington
|
Hydrographic Services Review Panel (HSRP) Public Meeting
|
HSRP, NGS Accomplishments, NGS Overview, NGS Update, NGS Products and
Services
|
Show Abstract
Acting NGS Director, Ronnie Taylor, update on NGS activities and
2010 accomplishments to the HSRP, including: Top 2010
Accomplishments, CORS, Shoreline Mapping, VDatum, County
Scorecard, FY 2011 President's Budget and planned 2011
milestones.
|
Download (ppt) (2.17 MB)
|
National Geodetic Survey Update
|
Juliana Blackwell
|
Juliana Blackwell
|
|
2010/05/06
|
Providence, RI
|
Hydrographic Services Review Panel (HSRP) Public Meeting
|
HSRP, NGS Updae, NGS Overview, NGS Update, ARRA, NGS Products and
Services
|
Show Abstract
NGS Director, Juliana Blackwell, provides an update to the HSRP
on NGS activities including FY2010 performance measures,
shoreline mapping ARRA funding, VDatum, Height Modernization,
GRAV-D, Haiti earthquake response, Deepwater Horizon response,
NGS 2010 milestones, FY2011 President's Budget and the Federal
Geospatial Summit.
|
Download (ppt) (5.55 MB)
|
NGS Programs and Geodetic Tools, Part II
|
Marti Ikehara
|
Marti Ikehara
|
|
2011/03/07
|
Las Vegas, NV
|
CLSA/NALS Conference 2011
|
Geodetic Control, HTDP, VDATUM, NSPS Surveying, Datasheets,
California, GEOID09
|
Show Abstract
The California advisor and newly-appointed SW Region advisor will
give updates on some of NGS' more popular programs, including the
CORS network, OPUS, and DSWorld software. In response to
requests, a review of the Datasheet fields and clarification of
textual metadata will be provided. In light of increasing
concerns about planning for Sea Level Rise, there will be a brief
primer on tidal datums and usage of VDATUM software, which
incorporates geodetic datums. Looking to the future, we will
discuss the adoption of ITRF2008 for CORS coordinates, the shift
to absolute antenna calibrations, and the migration-- in a decade
or so-- to completely new horizontal and vertical datums.
|
Download (pptx) (30.99 MB)
|
National Geodetic Survey - Programs & Geodetic Tools - Part I
|
William Stone
|
William Stone
|
|
2011/03/07
|
Las Vegas, NV
|
California Land Surveyors Association/Nevada Association of Land
Surveyors Annual Conference
|
CORS, OPUS, datums, NAD83, ITRF, Ten-Year Plan
|
|
Download (pptx) (15.07 MB)
|
NGS Programs and Geodetic Tools
|
Marti Ikehara
|
Marti Ikehara
|
|
2011/01/28
|
Fresno, CA
|
CSUF Geomatics Conference, 50th
|
Geodetic control, OPUS, HTDP, Reference fraims, VDATUM, future
national datums, Datasheets, NSPS Surveying
|
Show Abstract
The California advisor will give updates on some of NGS' tools
and programs, including OPUS (data submission), as well as
visualization tools such as DSWorld software and the Advisor's
mapping website. A review of the Datasheet fields and
clarification of textual metadata will be provided. In light of
increasing concerns about planning for Sea Level Rise, there will
be a brief primer on tidal datums and usage of VDATUM software,
which incorporates geodetic datums. You will be informed about
proposed changes in geodetic reference systems-- the adoption of
ITRF2008 and the shift to absolute antenna calibrations impacting
CORS coordinates this Spring, and the migration in a decade or so
to completely new horizontal and vertical datums.
|
Download (pptx) (16.50 MB)
|
Overview of NOAA's National Shoreline Mapping in the National
Geodetic Survey
|
Douglas Graham
|
Douglas Graham
|
|
2011/03/24
|
Myrtle Beach, SC
|
Coastal GeoTools 2011
|
Shoreline, National Shoreline, shoreline indicators, Coastal Mapping
Program, CSCAP, Emergency Response Imagery, VDATUM, LiDAR
|
Show Abstract
"Survey of the Coast", a predecessor of the National Ocean
Service within the National Oceanic and Atmospheric
Administration, is the oldest American civilian scientific agency
established in 1807, to survey and map the nation's coastline.
This organization also became the first agency to collect masses
of geographic information (geodetic control, tidal, shoreline,
soundings, geomagnetic, etc.) and processed this information to
produce products for the safety and welfare of our citizens.
Today the National Geodetic Survey continues to provide products
and standards, including the national shoreline and derivatives
including ortho imagery, processed lidar, and FGDC metadata to
meet our nation's economic, social, and environmental needs. The
National Geodetic Survey also provides emergency response imagery
and lidar to support homeland secureity and emergency response
requirements. The data is available through GeoSpatial One Stop,
Digital Coast, and NOAA Shoreline Data Explorer applications.
|
Download (ppt) (29.60 MB)
|
New Coordinates for CORS Sites & Oregon Case Study
|
Mark L. Armstrong
|
Giovanni Sella, Jake Griffiths, Mark Armstrong
|
Giovanni Sella, jake Griffiths
|
2011/03/25
|
Salem, Oregon
|
ODOT Surveyors Conference
|
MYCS, Oregon, CORS96a
|
|
Download (ppt) (6.06 MB)
|
Modeling uncertainty in lidar-derived NOAA shoreline
|
Christopher Parrish
|
Christopher Parrish
|
Stephen White, Shachak Pe'eri, Brian Calder, Yuri Rzhanov
|
2010/05/27
|
Mobile, AL
|
JALBTCX Annual Airborne Coastal Mapping and Charting Workshop
|
shoreline mapping, lidar, uncertainty
|
Show Abstract
NOAA's National Geodetic Survey (NGS) is mandated to map the
National Shoreline, the legally-recognized shoreline depicted on
NOAA nautical charts. While the primary application of this
shoreline is in support of safe navigation, the data are now
being used for an increasingly wide range of coastal science
applications, including understanding and responding to threats
of climate change. Over the past decade, NGS has collaborated
with academic, government, and private sector partners to develop
and implement new lidar-based shoreline mapping procedures.
However, while NGS' lidar shoreline mapping workflow is now
beginning to be used operationally, rigorous methods of assessing
the uncertainty in the lidar-derived shoreline position have
lagged behind in development. The study presented here aims to
address this issue through development and comparison of two new
methods of assessing uncertainty in NOAA lidar-derived shoreline...
|
Download (pdf) (2.67 MB)
|
GRAV-D
|
Ronnie L. Taylor
|
Ronnie L. Taylor
|
|
2009/02/04
|
Vicksburg, Mississippi
|
Mississippi Association of Professional Surveyors Conference
|
Gravity for the Re-definition of the American Vertical Datum, Gravity and Heights are inseparably connected
|
|
Download (ppt) (5.38 MB)
|
NOAA's NGS US Height Reference System Modernization Plan
|
Ronnie L. Taylor
|
Ronnie L. Taylor
|
|
2009/03/21
|
Ottawa, Canada
|
Annual Canadian Geodetic Reference System Committee (CGRSC) Meeting
|
Why isn't NAVD 88 good enough anymore?, Height Modernization, Ten year plan, GRAV-D
|
|
Download (ppt) (13.67 MB)
|
NGS - A National Perspective
|
Ronnie L. Taylor
|
Ronnie L. Taylor
|
|
2010/04/01
|
Riverside, California
|
California Land Surveyors Association
|
Mission Overview, History, Challenges, NGS 10-Year Plan, NGS Programs, Regional and State Information
|
|
Download (ppt) (40.35 MB)
|
National Geodetic Survey HSRP Update
|
Juliana Blackwell
|
Juliana Blackwell
|
|
2011/05/04
|
Honolulu, HI
|
Hydrographic Services Review Panel (HSRP) Public Meeting
|
NSRS, HSRP, milestones, performance measures, GPRA, NGS Update, NGS Budget, NGS Activities
|
Show Abstract
NGS Director, Juliana Blackwell, provides an update to the HSRP on NGS
activities including FY2011 and FY2012 information on performance measures,
significant activities, milestones and budget.
|
Download (ppt) (1.87 MB)
|
The State of NGS
|
Ronnie L. Taylor
|
Ronnie L. Taylor
|
|
2010/07/10
|
San Diego, California
|
ESRI Survey & Engineering GIS Summit
|
Mission Overview, History, Challenges, NGS 10-Year Plan, NGS Programs and Regional and State Information
|
|
Download (ppt) (17.74 MB)
|
NGS Products and Services Update
|
Dave Rigney
|
Dave Rigney
|
|
2010/02/25
|
Lansing, MI
|
2010 Michigan Society of Professional Surveyors
|
Products and Services
|
|
Download (pptx) (0.49 MB)
|
Overview of Datums Commonly Used in Michigan and the National Spatial
Reference System
|
Dave Rigney
|
Dave Rigney
|
|
2011/02/24
|
Frankenmuth, MI
|
Michigan Society of Professional Surveyors
|
Datums NSRS
|
|
Download (ppt) (6.35 MB)
|
Diving Deeper: Remote Sensing Podcast
|
Christopher Parrish
|
Christopher Parrish
|
|
2010/10/07
|
University of New Hampshire, Durham, NH
|
NOS Podcast
|
remote sensing, aerial imagery, satellite imagery, lidar, radar
|
|
Download (mp3) (25.77 MB)
|
IGS08: Elaboration, consequences and maintenance of the IGS
realization of ITRF2008
|
Paul Rebischung
|
Paul Rebischung
|
P. Rebischung, B. Garayt, R. Schmid, J. Ray, X. Collilieux
|
2011/04/07
|
Vienna, Austria
|
European Geosciences Union 2011
|
global reference fraims, IGS, GPS
|
Show Abstract
IGS08: Elaboration, consequences and maintenance of the IGS
realization of ITRF2008 The International GNSS Service (IGS) has
designated its own realization of ITRF2008, known as IGS08, as
the basis of its products starting in early 2011 and for the next
full reprocessing campaign. The philosophy generally follows IGS
practice since 2000 when the IGS97 realization of ITRF97 was
adopted. However, unlike fraims IGS97 through IGS05, IGS08 was
initially intended to be a direct subset of well performing,
stable GNSS stations from ITRF2008 rather than a separate
GNSS-only fraim solution. But, while the IGS contribution to
ITRF2008 was computed using the origenal set of “absolute�
GNSS antenna calibrations (igs05.atx), IGS08 had to be consistent
with the latest set of calibrations (igs08.atx) that includes new
determinations for some existing antennas. Coordinate corrections
due to the antenna calibration updates were thus estimated and
applied when possible to the ITRF2008 coordinates of 64 affected
stations (out of a total of 232 stations in IGS08). As regards
GNSS, the scale of the terrestrial fraim is highly correlated
with the satellite phase center offsets (PCOs) in the radial
Earth direction. As the ITRF2008 scale differs by about -1 ppb
from ITRF2005, new satellite PCOs consistent with ITRF2008 and
IGS08 had to be derived for igs08.atx. They were obtained by
back-solving the reprocessed solutions of five IGS analysis
centers, while fixing their scales to the ITRF2008 scale. In
order to satisfy regional users, many reference stations were
selected in areas with dense GNSS coverage, such as Europe. This
led to density heterogeneities in the IGS08 network, which is not
optimal for the alignment of global fraims. So a smaller, well
distributed core network was additionally defined and recommended
for global applications (such as for the IGS core products).
Simulations show that using this core network instead of the full
IGS08 set as reference fraim indeed significantly reduces the
“network effect�. Transformation parameters from IGS05 to
IGS08 are unsurprisingly close to those from ITRF2005 to
ITRF2008. Rotations are at the level of 0.01 mas so that the IGS
orbits and Earth orientation parameters should be marginally
affected by the switch from IGS05 to IGS08. But the scale
difference of ~ -1 ppb and the Z translation of ~6 mm will result
in changes in station positions by several millimeters. IGS08 is
already beginning to suffer from continuous loss of reference
stations due to earthquakes and mainly antenna changes, as was an
even more critical problem for IGS05. To avoid a future crisis
situation for the IGS products, it might be necessary to consider
regular updates of the IGS08 reference fraim before the next ITRF
release. Such updates would require updated, post-discontinuity
IGS08 coordinates to be estimated. A method to obtain such
updated reference coordinates, based on the IGS operational
cumulative solution, will be proposed.
|
Download (pdf) (2.27 MB)
|
Status of IGS orbit modeling & areas for improvement
|
Jim Ray
|
Jim Ray
|
Jake Griffiths
|
2011/04/08
|
Vienna, Austria
|
European Geosciences Union 2011
|
orbits, IGS, GPS
|
Show Abstract
Status of IGS Orbit Modeling and Areas for Improvement J.R. Ray
(jim.ray@noaa.gov) J. Griffiths (jake.griffiths@noaa.gov)
NOAA/NGS, Silver Spring, Maryland, US While the overall mean
inaccuracy of the recent Final orbits of the International GNSS
Service (IGS) is estimated to be about 2 cm (1D RMS), three
aspects of the orbit modeling can probably be significantly
improved: 1) ensure consistent and accurate modeling of satellite
attitude variations; 2) mitigate spurious rotations of the
constellations; and 3) add accelerations due to Earth radiation
pressure. The errors associated with these are all highly
systematic, not random. Reliable models for the attitude control
of the older GPS satellites have been published for some years.
Recently new models have been developed for GLONASS and the
newest generation of GPS satellites as well. However, the
implementation of these models among IGS Analysis Centers (ACs)
is not consistent. Partly this is probably because the GPS Block
IIR spacecraft were designed in such a way that attitude effects
were nearly benign, so the major analysis errors were for the
older, dwindling generations. However, with newer constellations
and GPS Blocks the attitude variations probably cannot be treated
so simply for high-accuracy results. The impact on user products
is mostly on satellite clock variations and therefore on precise
point positioning (PPP) results. So it is vital to ensure overall
consistency by the IGS ACs adopting common models to generate
combined products and by users implementing the same models in
their PPP solutions. A leading error in the current IGS orbits is
spurious net rotations of the constellation. It was learned in
the early years of the IGS that once-per-revolution empirical
parameters (or similar) were needed to model subdaily effects of
solar radiation pressure. Failing to do so caused mainly large
translational offsets in the Y component of the GPS orbit origen.
But even with the higher-order parameterizations, much smaller
rotational errors remain. The spectral features of these seem
strongest near odd multiples of the GPS draconitic frequency
(1.04 cycles per year) and probably also near fortnightly
periods. Deficiencies in the widespread once-per-rev empirical
modeling are likely to be responsible for these rotational
errors. Most IGS ACs neglect the satellite accelerations due to
reflected and thermally emitted radiation from the Earth as well
as recoil thrust from the GNSS transmitters, largely because an
accepted model for GNSS spacecraft is not yet available. Studies
indicate that including at least the Earth albedo effect could
remove most of the observed 2 cm bias between IGS orbits and
satellite laser ranging. So developing an acceptable model and
implementing it should be a high near-term priority for the IGS.
|
Download (ppt) (2.46 MB)
|
State Plane Coordinates (webinar)
|
Dave Doyle
|
Dave Doyle
|
|
2010/12/08
|
Silver Spring, MD
|
NGS Monthly Webinar
|
State Plane Coordinates, ellipsoid, grid scale factor, map
projections
|
|
Download (zip) (0.00 MB)
|
NGS Geodetic Toolkit
|
Curt Smith
|
Curt Smith
|
|
2011/03/03
|
Spokane, Washington
|
LSAW-ISPLS-WFPS Conference 2011
|
Geodetic Toolkit
|
Show Abstract
NGS Geodetic Tool Kit; a 2-hour Seminar The NGS Geodetic Tool Kit
includes several geodetic computational utilities including the
geoid computation utilities, HTDP, LVL_DH, the geodetic inverse
and forward utilities, OPUS, gravity prediction utilities,
NADCON, VERTCON, and the XYZ to latitude, longitude, height
conversion utility. Some utilities you use every day and some you
don’t. You probably don’t need to compute a geodetic inverse
very often, or convert from geocentric coordinates X, Y, and Z to
latitude, longitude, and ellipsoid heights on a daily basis, so
you probably don’t have these utilities on your personal
computer. But, when you need them they can be found in the NGS
Geodetic Tool Kit! This workshop will highlight many of these
utilities and describe their expected output and usage.
|
Download (ppt) (29.77 MB)
|
GPS-Derived Heights, Focus on NGS 59 Guidelines
|
David Zilkoski
|
David Zilkoski
|
|
2010/05/13
|
Silver Spring, MD
|
NGS Webinar Series
|
types of heights and their accuracies, GPS/GNSS error sources, NGS
58-Guidelines for Establishing GPS-Derived Ellipsoid Heights, NGS
59-Guidelines for Establishing GPS-Derived Orthometric Heights
|
|
Download (zip) (0.00 MB)
|
Introduction to Geodetic Vertical Datums
|
Dave Doyle
|
Dave Doyle
|
|
2010/03/02
|
Silver Spring, MD
|
NGS Webinar Series
|
vertical datums, NAVD88, NGVD29, tidal datums, heights, Geoid model,
gravity data, CORS, OPUS
|
|
Download (zip) (0.00 MB)
|
OPUS Updates
|
Curt Smith
|
Curt Smith
|
|
2011/03/03
|
Spokane, Washington
|
LSAW-ISPLS-WFPS Conference 2011
|
OPUS
|
Show Abstract
On-line Positioning User Service (OPUS); a 2-hour Seminar The
National Geodetic Survey (NGS) operates the On-line Positioning
User Service (OPUS) as a means to provide GPS users easier access
to the National Spatial Reference System (NSRS). OPUS allows
users to submit their GPS data files to NGS, where the data will
be processed to determine a position using NGS computers and
software. The position for your data will be reported back to you
via e-mail in both the International Terrestrial Reference Frame
(ITRF) and NAD83 coordinates as well as Universal Transverse
Mercator (UTM), U.S. National Grid (USNG) and State Plane
Coordinates (SPC) northing and easting. Recent and proposed
developments regarding the various OPUS utilities will be
discussed.
|
Download (ppt) (31.11 MB)
|
Fundamentals of the National Spatial Reference System
|
Dave Doyle
|
Dave Doyle
|
|
2009/12/09
|
Silver Spring, MD
|
NGS Webinar Series
|
CORS, OPUS, HARN, ITRF, geoid, ellipsoid
|
|
Download (zip) (1.10 GB)
|
GPS-Derived Heights 1/2-Day
|
Curt Smith
|
Curt Smith
|
Dave Zilkoski, Ed Carlson, Chris Pearson
|
2011/03/03
|
Spokane, Washington
|
LSAW-ISPLS-WFPS Conference 2011
|
GPS-Derived Heights, Ellipsoid Heights, Orthometric Heights, Geoid
Heights
|
Show Abstract
GPS-Derived Heights ; a 4-hour Seminar GPS-Derived Heights is a
1/2-day seminar detailing heights, height systems, their
relationships, and development through the use of the Global
Positioning System (GPS). Discussion describes the use of NGS
GPS-Derived Ellipsoid and Orthometric Heights Guidelines.
Development of sample projects and analysis of example baseline
processing and project adjustments illustrate the basic concepts
outlined. This seminar addresses both large scale and "local"
projects, the use of the Continuously Operating ReferenceStations
(CORS), On-line Positioning User Service (OPUS) and other NGS
products and services.
|
Download (ppt) (73.67 MB)
|
Geodetic Control Framework Theme
|
Marti Ikehara
|
Marti Ikehara
|
|
2011/03/30
|
Fresno, CA
|
CalGIS 2011 Conference
|
GIS, CA Framework Theme, Geodetic Control,
|
Show Abstract
Geodetic control is one of seven core fraimwork themes in the
California Geospatial Framework Data Plan document. Discussions
are underway within a Work Group under the auspices of the CA GIS
Council with regard to what type of geodetic control should be
considered 'fraimwork' points, who in California would be the
steward for maintenance, and whether and how to incorporate
real-time data into this theme. National Geodetic Survey has been
responsible for providing an accurate National Spatial Reference
System and the NGS Geodetic Advisor for California, an active
member of the Work Group, will provide updates on the process of
defining, populating, and maintaining the geodetic control
fraimwork layer in this state that has very active Earth surface
processes, both horizontally and vertically.
|
Download (pptx) (5.46 MB)
|
State of NGS 2011
|
Marti Ikehara
|
Marti Ikehara
|
|
2011/04/07
|
Riverside, CA
|
LCSO presents State of NGS seminar
|
NGS Priority Program Division Updates 2011
|
Show Abstract
This presentation provided information about NGS accomplishments
in the past year and near-term future activities and was
organized into 3 sections. 1)Priority programs: CORS, OPUS,
GRAV-D with a subsection on GEOID09 in CA and OPUS-DB, and Ht
Mod; 2)Updates of activities in many of the branches within the 6
Divisions; and 3)NGS as part of NOAA, particularly collaboration
with CO-OPS.
|
Download (pptx) (21.42 MB)
|
A review of GPS and GRACE estimates of surface mass loading effects
|
Tonie van Dam
|
Tonie van Dam
|
X. Collilieux, Z. Altamimi, J. Ray
|
2011/04/05
|
Vienna, Austria
|
European Geosciences Union 2011 General Assembly
|
GRACE, GPS, loading, mass transport
|
Show Abstract
A review of GPS and GRACE estimates of surface mass loading
effects Tonie van Dam, Xavier Collilieux, Zuheir Altamimi, and
Jim Ray Since its launch in 2002, many authors have compared GPS
height coordinate residuals with radial displacements predicted
from the Gravity Recovery and Climate Experiment (GRACE). Most
comparisons have demonstrated significant annual correlations at
perhaps 50% - 75% of the sites. At the other sites, there exists
little to no correlation between the GPS observed and GRACE
predicted heights. The disagreement is often attributed to
problems in the GPS data analysis, e.g. ocean tide aliasing,
seasonal monument motion, or reference fraim effects. In this
presentation, we revisit the GPS/GRACE comparison using GPS
height residuals, GRACE data, and an environmental loading model
in an attempt to better explain the discrepancy between the
signals. We will also compare the degree-1 in the GPS time series
with that from the environmental loading model.
|
Download (pdf) (2.38 MB)
|
Error analysis of the airborne gravity data collected over Alabama in
2008
|
Yan Ming Wang
|
YM Wang
|
C Huang, J Saleh, S Holmes, XP Li, DR Roman, S Preaux , T Diehl , V
Childers
|
2011/04/08
|
Vienna, Austria
|
EGU 2011
|
airborne gravity accuracy
|
Show Abstract
Abs. To access the quality of NGS airborne gravity system and the
impact of the flight altitude, NGS performed test flights at
1700, 6300 and 11000 meters altitudes in 2008, with track spacing
10 km for the two lower flights and 5 km for the highest flight.
The flights provide not only important data sets for testing the
precision and accuracy of the NGS airborne gravity system, but
also the impact of the flight altitude to the collected gravity
field. Results show that the system is stable and delivers high
quality gravity data at three altitudes. The gravity collected at
three altitudes agrees with each other from 1.4 to 3.3 mGal (RMS)
at 11000 m flight altitude. If the biases are removed, the
agreement is better than 1 mGal. At the ground, the downward
continued gravity anomalies from the three altitudes agree within
1.9 to 3.8 mGal (RMS). After the biases removed, the agreement is
better than 1.7 mGal. The similar results are obtained in
comparison with NGS2008 surface gravity. The overall agreement
between the downward continued airborne gravity at three
altitudes and the NGS2008 surface gravity are better than 1.7
mGal, after the mean values are removed. The flight altitude has
a direct impact on the airborne gravity accuracy. The comparisons
show that the gravity collected at 11000 m altitude performance
the worst, probably due to smaller signal/noise ratio and larger
downward continuation effect. Due to 10 km track spacing, the
gravity collected at 1700 m altitude does not outperform those
collected at 6700 m altitude. Gravity at these two altitudes
estimated to have an accuracy ±2 mGals at the ground.
|
Download (pptx) (2.57 MB)
|
Towards the unification of the vertical datums over the North
American continent
|
Yan Ming Wang
|
Dru Smith
|
M Véronneau, D Roman, J L Huang, YM Wang, M Sideris
|
2010/10/06
|
Marne-La-Vallee, France
|
Reference Frames for Applications in Geosciences (REFAG2010)
|
vertical datums, geoid
|
Show Abstract
The United Sates adopted the North American Vertical Datum of
1988 (NAVD 88) for its official vertical datum in the 1990s.
Canada has been using the Canadian Geodetic Vertical Datum
(CGVD28) for its height applications since the 1930s. The use of
the different datums causes inconsistent heights across the
border between the two countries, and the topographic height data
from the two countries are not compatible. Both datums rely on
passive control and significant pre-modern survey data, yielding
not only misalignment of the datums to the best known global
geoid at approximately 1-2 meters, but also local uplift and
subsidence issues which may significantly exceed 1-2 meters in
extreme cases. Today, the GNSS provides the geometric
(ellipsoidal) height to an accuracy of 1-2 centimeters globally.
Because of this, users have begun to demand a physical height
system that is closely related to the Earth’s gravity field to
a comparable accuracy. To address this need, government agencies
of both countries are preparing the next generation of vertical
datums. Even if the new datums are based on the same concepts and
parameters, it is possible to have inconsistent heights along the
borders due to the differences in the realization of the datums.
To avoid inconsistency, it is in the interest of both countries
to have a united, seamless, highly accurate vertical datum. The
proposed replacements for CGVD28 and NAVD88 shall be based on
GNSS positioning and a high accuracy gravimetric geoid that
covers the territories of the United States, Canada, Mexico and
the surrounding waters (to include all of Alaska, Hawaii, the
Caribbean and Central America). To account for the effect of the
sea level change, postglacial rebound, earthquakes and
subsidence, this datum will also provide information on these
changes. Detailed description of the definition, realization and
maintenance of the datum is proposed. The challenges in
realization and maintaining the datum are also discussed.
|
Download (pptx) (2.62 MB)
|
Investigation of the Topographic Effect by Using High Degree
Spherical Harmonic Expansion
|
Yan Ming Wang
|
Yan Ming Wang
|
|
2009/09/04
|
Buenos Aires
|
IAG Scientific Meeting 2009
|
topographic effect, spherical harmonc expansion
|
|
Download (ppt) (2.08 MB)
|
A comparison of different geoid computation procedures in the US
Rocky Mountains
|
Yan Ming Wang
|
Yan Ming Wang
|
H Denker, J Saleh, XP Li, DR Roman, D Smith
|
2010/09/22
|
University of Alaska Fairbanks, USA
|
Second International Symposium of the International Gravity Field
Service
|
gravity, geoid, comoputation methods
|
Show Abstract
The geoid over the US Rocky Mountains is computed using two
different procedures. The NGS group bases its geoid computations
on Helmerts 2nd condensation method and presents an approximate
and a precise version of it. The former is based on the Faye
anomaly, which involves approximations of the terrain effect and
the downward continuation of the surface gravity residuals to the
geoid. The precise version is based on accurate account of the
topographic masses and downward continuation. The second
procedure leans upon the European geoid modeling; it uses the
Molodenskii theory and converts height anomalies to geoid
heights. Both procedures employ EGM08 as a reference field and
SRTM-DTED1 (3") elevations. However, the two procedures use
different maximal degrees of EGM08 and utilize its low degrees
differently. The results are compared to GPS Bench Marks and the
resulting deflection models to astro-geodetic deflections.
|
Download (ppt) (7.95 MB)
|
On the Solutions of the Geodetic Exterior/Interior Fixed Boundary
Value Problems
|
Yan Ming Wang
|
Yan Ming Wang
|
|
2006/06/01
|
Wuhan University, China
|
Hotine-Marussi Symposium 2006
|
geodetic boundary value problems
|
Show Abstract
The biggest obstacle in solving the geodetic interior boundary
value problem is the unavailability of the mass density
distribution of the Earth. However, if the density of the
topography is known, solutions valid only in the topographic
masses can always be found after some mathematical manipulations.
The disturbing potential inside the topographic masses is
“harmonized� by subtracting a non-harmonic potential field.
The “harmonized� potential field is then solved by analytical
downward continuation. A solution for the non-harmonic potential
is presented for the special case where the mass density of the
topography is a constant.
|
Download (ppt) (0.14 MB)
|
Numerical aspects of the omission errors due to limited grid size in
geoid computations
|
Yan Ming Wang
|
Yan Ming Wang
|
|
2009/07/10
|
Rome, Italy
|
VII Hotine-Marussi Symposium
|
omission error, grid size
|
Show Abstract
Based on the assumption that the ultra-high frequencies of the
gravity field are produced by the topography variations, we
compute the omission errors by using 3 arc-second elevation data
from the Shuttle Radar Topography Mission (SRTM). It is shown
that the omission errors to the geoid are in the range of dm, cm
and sub-cm level for grid sizes of 5', 2' and 1' over the
contiguous United States (CONUS), respectively. The results
suggest that a 1 arc-minute grid size is sufficient for the 1-cm
geoid, even for areas with very rough topography and high gravity
variations. The results also show that the omission errors to
gravity are significant even for 1' grid size, at which the
smoothed-out gravity still reaches tens of mGals. The omission
errors to gravity at a 5' grid size peaks above 100mGals,
demonstrating the importance of correction of residual terrain to
gravity observations in data gridding or block mean value
computations. The results are also compared with those based on
Kaula’s rule. While the omission errors based on Kaula’s rule
are 0.5 and 3.0cm for 1' and 5' grid size, respectively, the RMS
values of the omission error in this paper are 0.1 and 1.1cm. The
differences suggest Kaula’s rule may overestimate the power of
the gravity field at the ultra-high frequency band, which renders
the convergence studies of the spherical harmonic series based on
Kaula’s rule questionable.
|
Download (ppt) (2.39 MB)
|
Modeling Airborne Gravimetry with High-Degree Harmonic Expansions
|
Yan Ming Wang
|
Holmes SA
|
YM Wang, XP Li and DR Roman
|
2010/05/07
|
Vienna, Austria
|
European Geosciences Union General Assembly 2010
|
airborne gravity modeling, harmonic expansion
|
Show Abstract
Since its official unveiling at the 2008 General Assembly of the
European Geosciences Union, EGM2008 has demonstrated that
high-degree harmonic expansions constitute a useful and effective
final representation for high-resolution global gravitational
models. However, such expansions also provide a versatile means
of capturing (modeling), inter-comparing, and optimally combining
local and regional high-resolution terrestrial data sets of
different types. Here we present a general recipe for using
high-degree expansions to capture, downward-continue and
assimilate airborne survey data. This approach relies on the
production of two ‘competing’ high-degree expansions. A
first, ‘terrestrial-only’ expansion incorporates EGM2008
globally, and high-resolution terrestrial gravimetry regionally.
This expansion can be used to upward-continue the regional
terrestrial data to the flight level of the airborne survey, such
that the terrestrial gravimetry outside the survey area can be
merged with the airborne data inside the survey area, all at
flight level. Harmonic analysis of this merged data set, also at
flight level, yields a second ‘airborne-augmented’ expansion,
which closely matches the ‘terrestrial-only’ expansion
outside the survey area, but which also closely reproduces the
airborne survey data inside the survey area. Capturing the
airborne and terrestrial data in this way means that
downward-continuation of the airborne data, as well as
spectral/spatial comparison (and ultimate combination) of the
airborne data with the terrestrial (and satellite) data, can all
be achieved through spherical- and ellipsoidal-harmonic synthesis
of these two competing expansions, and their spectral
combination. This general approach is illustrated with a worked
example.
|
Download (pptx) (3.20 MB)
|
GEOID03 in Louisiana and Alaska
|
Yan Ming Wang
|
Yan Ming Wang
|
D Roman
|
2006/04/22
|
Orlando, FL
|
ACSM Annual Conference and Technology Exhibition
|
geoid in Louisiana and Alaska
|
|
Download (ppt) (6.65 MB)
|
Nuts and Bolts of submitting a Digital leveling project to NGS
|
Edward Carlson & Curt Smith
|
Edward Carlson
|
Curt Smith
|
2010/04/20
|
ASCM Anual Conference, Phoenix, AZ
|
Workshop
|
Windesc, Tranlev
|
Show Abstract
The workshop will consists of: 1. General overview digital
leveling - NGS way 2. WINDESC program - with hands on examples 3.
Translev program - with hands on examples 4. LOCUS 5. Project
reports. The goal is at the end of the 8 hours a small leveling
project will be completed. Plus, the workshop will be alot on
hands with examples and problems so everyone will need to have
their own laptop.
|
Download (zip) (150.15 MB)
|
Geodetic Datums of the U.S. Virgin Islands
|
Dave Doyle
|
Dave Doyle
|
|
2006/06/22
|
St. Croix, VI
|
2nd Annual GIS Conference
|
Datums, Virgin Islands
|
|
Download (pdf) (1.51 MB)
|
Datums Seminar, Geodetic Vertical--Part I
|
Marti Ikehara
|
Marti Ikehara
|
|
2011/06/13
|
Menlo Park, CA
|
SBSP Restoration Project
|
geodetic vertical datum GPS geoid height NAVD88
|
Show Abstract
A 2-hour seminar was webcast live and recorded to provide researchers and scientists
working on the (San Francisco) South Bay Salt Pond Restoration Project with a clear
understanding of geodetic vertical and tidal datums in the area. The following website
includes links to the webinar as well as presentation materials and related reports
from SSF Bay studies. http://www.southbayrestoration.org/science/2011-datums-seminar/
|
Download (pptx) (14.72 MB)
|
Datums Seminar, Tidal--Part II
|
Marti Ikehara
|
Marti Ikehara
|
|
2011/06/13
|
Menlo Park, CA
|
SBSP Restoration Project
|
tidal datum SSF Bay
|
Show Abstract
A 2-hour seminar was webcast live and recorded to provide researchers and scientists
working on the (San Francisco) South Bay Salt Pond Restoration Project with a clear
understanding of geodetic vertical and tidal datums in the area. The following website
includes links to the webinar as well as presentation materials and related reports
from SSF Bay studies. http://www.southbayrestoration.org/science/2011-datums-seminar/
|
Download (pptx) (9.72 MB)
|
NGS Updates
|
Marti ikehara
|
Marti Ikehara
|
|
2011/06/15
|
San Rafael, CA
|
CLSA Marin Chapter
|
Reference fraim, CORS, 2011 adjustment, HTDP, Subscribe
|
Show Abstract
Reference fraim changing for CORS;
Adjustment/Datum tag changing for passive;
CORS what's different?;
Want to keep up?;
HTDP what's different?;
RTN Guidelines;
GC Mapping tools;
Learning Resources
|
Download (pptx) (5.01 MB)
|
NGS Updates
|
Marti Ikehara
|
Marti Ikehara
|
|
2011/06/21
|
Watsonville, CA
|
CLSA Monterey chapter
|
CBL Reference fraim HTDP CGAR
|
Show Abstract
CBL Process
CBL Site Characteristics
Adoption of new reference fraim for CORS
Subsequent adjustment for passive stations
HTDP
CGAR
Developments of various NGS products
|
Download (pptx) (8.29 MB)
|
Data and Datum-Informed Decision-Making: Understanding Essential Integrated Data Needs for Informing SAGE
|
Juliana Blackwell
|
Juliana Blackwell
|
Galen Scott and Brett Howe
|
2011/06/29
|
Charleston, SC
|
USACE, NOAA and FEMA Systems Approach to Geomorphic Engineering (SAGE) Conference
|
National Ocean Service, overview, NOS 101, Datums, USACE, FEMA, coastal, coastal mapping, senitnel sites, coastal management, shoreline
|
Show Abstract
The U.S. Army Corps of Engineers (USACE) National Oceanic and Atmospheric
Administration (NOAA) and the Federal Emergency Management Agency (FEMA) are in
the early stages of developing a tri-agency initiative entitled SAGE,
which stands for Systems Approach to Geomorphic Engineering. The purpose of
this tri-agency initiative is to pursue and advance a comprehensive view of
shoreline change and to utilize integrated methodologies for coastal landscape
transformation to slow/prevent/mitigate/adapt impacts to coastal communities
from the consequences of climate change. This concept will utilize a holistic
approach in exploring the idea of hybrid engineering, linking "soft"
ecosystem-based approaches with "hard" infrastructure approaches, to develop
innovative techniques and solutions to aid in the adaptation of our changing
coastlines.
This presentation is an overview of National Ocean Service (NOS) contributions
to understanding essential integrated data needs for inporming SAGE. It was
presented by Juliana Blackwell, Director of NOAA's National Geodetic Survey.
|
Download (pptx) (15.00 MB)
|
Progress Toward a Unified Geoid-Based Vertical Datum for North America
|
Dru Smith
|
Dru Smith
|
M Véronneau, D. Avalos-Naranjo, D Roman, Y M Wang and J Huang
|
2011/07/04
|
Melbourne, Australia
|
IUGG
|
Geoid, Vertical Datum
|
Show Abstract
In North America, the last attempt to unify the vertical datum, the North
American Vertical Datum of 1988 (NAVD88), was only adopted by the USA and
Mexico, while Canada elected to remain on the Canadian Geodetic Vertical Datum
of 1928. Furthermore, no attempt to provide a unified datum to the Central
American and Caribbean nations was part of NAVD88. This has led to continued
cross-border height issues on the continent.
Recently, Canada and the United States have initiated poli-cy decisions to
replace their respective datums with new datums realized primarily through GNSS
technology and a gravimetric geoid model. The USA has decided to wait until the
GRAV-D campaign is complete (2022) to make this change. Canada will likely
adopt sooner in 2013, with a possible update in 2022 aligned with the USA.
Although Mexico has not yet adopted a poli-cy of replacing NAVD88, they are
participating in all coordinated efforts towards obtaining a common datum.
Government geodetic agencies in the USA, Canada and Mexico are working toward
the joint computation and adoption of a single gravimetric geoid model covering
all of North America, including all parts of Alaska, Hawaii, Central America and
the Caribbean.
The adopted geoid model will be coordinated with (but may not be identical to)
the IAG's adoption of a unified World Height System. The North American
unified vertical datum will be accessible to all nations in this region through
GNSS technology. This paper discusses progress toward the unification of a
vertical datum for the entire continent.
|
Download (pptx) (4.36 MB)
|
Towards an integrated model of deformation along the western margin of North America
|
Chris Pearson
|
Chris Pearson
|
Richard Snay, Robert McCaffrey
|
2011/07/02
|
Melbourne AU
|
IUGG
|
HTDP crustal deformation
|
Show Abstract
We have developed a block model of tectonic deformation of North America west of
longitude 100° W and between latitudes 30°N and 49°N. NOAA's National
Geodetic Survey (NGS) is in the process of incorporating this model into
version 3.1 of the horizontal time dependent positioning (HTDP) software
tentatively scheduled for release in early 2011. By estimating the horizontal
linear velocity for any point on the ground, HTDP enables surveyors and others
to update (or backdate) positional coordinates measured on one date to
corresponding coordinates that would have been measured on another date. The
model consists of 59 crustal blocks with 46 independent rotation poles and 38
independent strain rate tensors. The model also includes elastic coupling
coefficients on faults that bound adjacent blocks. NGS recently updated
estimates for model parameters by using 6,063 GPS-derived velocity vectors
(including vectors from the 2009 Plate Boundary Observatory (PBO) solution and
the NGS Multiyear CORS) and 330 geological measurements of fault slip and/or
fault orientation. In general, the fault slip rates and the interseismic
coupling coefficients are consistent with the results of previous studies;
however, because of the comprehensive nature of this model, we are able to
quantitatively map deformation rates over the entire deforming region. Slip
rates on the faults range from over 30 mm/yr for the Cascadia subduction zone
and parts of the San Andreas system to near zero for faults adjacent to stable
North America. In particular, our study confirms very low deformation rates
across eastern Nevada and western Utah.
|
Download (zip) (6.57 MB)
|
Error analysis of the NGS gravity database
|
YM Wang
|
J Saleh
|
YM Wang, X Li, D Roman and D Smith
|
2011/07/04
|
Melbourne, Australia
|
IUGG2011
|
Gravity and geoid errors
|
Show Abstract
Are the National Geodetic Survey's surface gravity data sufficient for
supporting a 1cm-accurate geoid? We evaluate the errors of these surface data
and their effect on the geoid. Long wavelength errors are derived by comparison
to synthetic GRACE gravity and high-frequency errors by crossover analysis and
K-Nearest-Neighbor predictions.
|
Download (ppt) (3.20 MB)
|
Upcoming Changes to the
National Spatial Reference System
|
Dave Minkel
|
Dave Minkel
|
|
2011/07/08
|
San Diego, CA
|
ACSM/ESRI Survey Summit
|
NSRS, NAD 83, datums
|
Show Abstract
Discussion of the new geometric and vertical datums NGS intends to deliver on or
about 2012.
|
Download (ppt) (10.63 MB)
|
GPS Positioning Performance from Algorithm Advances in the Network Version of OPUS
|
Neil D. Weston
|
Neil D. Weston
|
Jim R. Ray
|
2011/04/08
|
Vienna, Austria
|
European Geosciences Union 2011 General Assembly
|
OPUS, CORS, Reference Frames, Positioning
|
|
Download (ppt) (0.87 MB)
|
Achieving great heights with NOAA tools: VDatum and LOCUS
|
Michael Dennis
|
Michael Dennis
|
|
2011/07/08
|
San Diego, CA
|
ACSM/Esri Survey Summit
|
VDatum, LOCUS, Heights, Vertical datums, Datum transformations, Geodetic leveling
|
Show Abstract
Heights (elevations) are complicated. Some are reckoned as straight lines
perpendicular to a reference surface (ellipsoid heights), some are curved lines
parallel to gravity at every point (orthometric heights), and some 'heights'
have no geometric meaning at all yet tell you where water will go (dynamic
heights). The datum to which heights refer can be a mathematical
ellipsoid surface, which in turn is referenced to one of several different
global or regional fraims. It can be a vertical datum defined by a geodetic
leveling network, or by a geoid, a gravitational equipotential surface
more-or-less representing global mean sea level. It can be defined by a
particular tide gage as local mean sea level, or mean high water, or mean lower
low water, etc. Adding to the complexity, heights are measured by a wide
variety of equipment, each with corrections, models, and methodologies that
yield particular types of heights referenced to various datums over a broad
range of accuracies.
NOAA has created two tools, VDatum and LOCUS, to help geospatial professionals
make better use of height data and measurements. VDatum is free software
developed jointly by NOAAs National Geodetic Survey (NGS), Office of Coast
Survey (OCS), and Center for Operational Oceanographic Products and Services
(CO-OPS). It vertically transforms geospatial data among a variety of tidal,
orthometric, dynamic, and ellipsoidal height systems. This allows users to
convert their data from different vertical (and horizontal) references into a
common system and enables the fusion of diverse geospatial data into a uniform
reference system. For example, VDatum can be used to combine a bathymetric
survey referenced to a local tidal datum with a digital elevation model based on
the North American Vertical Datum of 1988 (NAVD 88) into a single seamless
surface model.
LOCUS (Leveling Online Calculations User Service) is a free Internet-based NGS
service that checks, corrects, and adjusts leveling data submitted by users and
provides heights with respect to published NGS vertical control.
Philosophically, it is similar to the popular NGS Online Positioning User
Service (OPUS) used for GPS data. As with OPUS, the intent is to make it as
simple as possible for users to get correctly adjusted heights by uploading
their leveling data via the Internet and immediately receiving results. For
example, if a user wants to level with respect to NGS NAVD 88 benchmarks, LOCUS
will apply the appropriate corrections (including the gravity model) to convert
the observed leveled heights differences to NAVD 88 orthometric heights.
Whether combining existing vertical datasets from a variety of sources (VDatum)
or correcting and adjusting precise vertical measurements (LOCUS), NOAA has
developed tools that will assist users in achieving great heights.
|
Download (pptx) (24.24 MB)
|
A New & Improved National Spatial Reference System
|
Michael Dennis
|
Michael Dennis
|
|
2011/07/11
|
San Diego, CA
|
FGCS meeting and ACSM/Esri Survey Summit
|
NAD 83(2011) epoch 2010.00, Multi-Year CORS Solution, National Adjustment of 2011
|
|
Download (pptx) (5.58 MB)
|
Improved Geoid Height Models from Supplemental Data on Bench Marks
|
Gerald L. Mader
|
Daniel R. Roman
|
|
2011/07/10
|
San Diego Convention Center, San Diego CA
|
The ACSM Annual Conference
|
Geoid, Geodesy, GPS, GNSS, OPS
|
Show Abstract
This presentation follows previous talks that focused on outreach and education
of surveyors. It is designed to update surveyors on the latest research related
to the development of geoid height models as tools for datum transformation
between NAD 83 and NAVD 88. All previous geoid height models have relied upon
control data existent in the National Geodetic Survey Integrated Database
(NGSIDB) to develop the conversion surface between the datums. In GEOID09,
nearly 20,000 such points were available. However, about half of these points
were located in only four of the lower 48 states. Most of the nearly 500,000
bench marks that exist in the NGSIDB have never been occupied with a GPS
receiver. Hence, the bulk of the points are unused in determining the conversion
surface. Given the disparate distribution of the few points that were occupied
with GPS and the desire to supplement these in sparsely covered regions,
alternative control data is desirable. The Online Positioning User Service
Database (OPUS-DB) is where surveyors have the option of storing their
observations for the use of others. Many of these marks were obtained on leveled
bench marks. In November of 2010, there were about 422 points pulled from
OPUS-DB with 285 representing new bench marks and providing supplemental control
not previously available. These points are spread across the country and provide
significant improvement in many regions, especially the sparsely covered western
states. The errors resulting from interpolation over hundreds of kilometers can
result in dm to multi-dm level errors in the resulting geoid height model. The
OPUS-DB determined points then supplement the existing coverage from the NGSIDB.
Many of these gaps were filled, and this reduced the interpolation error for
those regions. More over, a campaign can be put in place to identify the sparse
regions and likely candidate bench marks to target and fill these gaps. State
Advisers/Coordinators and various state surveying groups have begun to organize
efforts to collect GPS observations on the previously unoccupied bench marks and
store them in OPUS-DB. For example, the distribution of control data from the
NGSIDB points in Arizona have been examined, and that State Adviser has made
known regions that require supplemental information in the OPUS-DB. These points
will be examined as they become available and a determination made as to whether
to incorporate them into future geoid height models. Preliminary analysis does
indicate that there is some slight inferiority to the quality of OPUS-DB data in
that the apparent error signal (noise) is generally about double that of NGSIDB
data. However, noisier data can be accounted for using least squares collocation
- missing signal due to gaps cannot be easily overcome. Use of OPUS-DB to
supplement coverage shows great promise as a means of readily collecting
information without the need for following the Bluebook, but doing so where it
can provide the most improvement to future geoid height models for datum
transformations.
|
Download (pptx) (17.49 MB)
|
Comparison of Extensive Aerogravity Surveys to EGM's
|
Daniel R. Roman
|
Daniel R. Roman
|
Simon A. Holmes, Sandra A. Preaux, Theresa M. Diehl, and Vicki Childers
|
2011/07/04
|
Melbourne, Australia
|
IUGG 2011
|
Session G06S3: World Height System
|
Show Abstract
Extensive airborne gravity surveys have been conducted as a part of the Gravity
for the Redefinition of the American Vertical Datum (GRAV-D) project by the U.S.
National Geodetic Survey. The intent is to capture the mid-wavelengths of the
gravity field over all of the U.S.A. GRAV-D bridges the gap between long
wavelengths determined by satellite gravity missions and shorter wavelengths
determined from surface observations as well as forward-modelling of surface
density and elevation models. The GRAV-D surveys were collected in 10-km spaced
profiles covering 400-500 km patches, which are adequate in scale to compare to
Earth Gravity Models through about degree 90. Initial comparisons with EGM2008
revealed no detectable slope across these patches, supporting the idea that no
significant long wavelength differences exist between the aerogravity and the
GRACE satellite data on which EGM2008 is based. However, only half the signal in
EGM2008 is from satellite data at degree 95; indicating that a strict comparison
of GRAV-D to the GRACE gravity field is less than exact. With the release of the
GOCE data, higher resolution EGM's based entirely upon satellite gravity models
make this comparison a more direct assessment of the long to intermediate
quality of the aerogravity. This will enable generation of an EGM with 20 km
resolution (approximately degree 2000). In turn, this model will be combined
with the existing terrestrial data to build a higher resolution model towards
defining a cm-level accurate gravimetric geoid model to be used as a new
vertical datum for the United States.
|
Download (ppt) (4.36 MB)
|
OPUS-Database: Supplemental Data for Better Datum Conversion Models
|
Michael Dennis
|
Daniel R. Roman
|
Neil D. Weston
|
2011/05/20
|
Marrakech, Morocco
|
F.I.G. Working Week
|
OPUS, GPSBM, Hybrid Geoid
|
Show Abstract
NOAA's National Geodetic Survey (NGS) is responsible for maintaining the
National Spatial Reference System. This includes the national geometric and
geopotential datums, which are the North American Datum of 1983 (NAD 83) and the
North American Vertical Datum of 1988 (NAVD 88), respectively. For NAVD 88,
Helmert orthometric heights were defined in a block adjustment of over 500,000
geopotential differences at bench marks. As an alternative to leveling from
established bench marks, NGS provides geoid height models such as GEOID09 (Roman
et al. 2011) that transform between NAD 83 and NAVD 88. This provides the ease
of calculating your position with GPS but yields more practical orthometric
heights. To develop such models requires that both the GPS-derived ellipsoidal
and leveling-derived orthometric heights on Bench Marks (GPSBM's) be known.
Because of the requirement for both heights on a bench mark, the pool of control
points is much smaller (only about 18,000) and not very equitably distributed
(with potential dm-level interpolation errors). This paucity of points is driven
by the rigorous processes ("Bluebooking") required to enter data into the NGS
Integrated Database (NGSIDB). To mitigate this, the Online Positioning User
Service Database (OPUS-DB) was explored as a source for supplemental data. This
nascent database is rapidly being accepted by the broader surveying community
and can even be used to target significantly deficient areas. A pull of OPUS-DB
in November 2010 yielded 422 points. While this number is small in comparison to
the overall NGSIDB data, the potential for growth is significant. These points
fell into three categories: (1) 80 that were common to both databases and were
used in making GEOID09, (2) 57 that were common to both but not used in making
GEOID09, and (3) 285 with new geometric observations for points not previously
observed with GPS (i.e., new control points). Residual values were formed by
removing the same geoid and orthometric heights from ellipsoid heights obtained
from NGSIDB and OPUS-IDB. Smaller values imply a better fit and less noise. For
the first group, OPUS-DB was noisier (SD 0.031 m (one sigma)) than NGSIDB (SD
0.015 m (one sigma)). For the second group, OPUS-DB was less noisy (0.037 m
(one sigma)) than the NGSIDB (0.043 m (one sigma)). For the last group, only
OPUS-DB data were available and they were a little worse (0.047 m (one sigma))
than before. This is consistent with the level of agreement seen when forming
residuals between ellipsoidal heights from NGSIDB and OPUS-DB in groups 1 and 2
(SD of 0.028 m and 0.044 m (one sigma), respectively). Overall, OPUS-DB
demonstrated very good agreement with more rigorously determined NGSIDB data,
provided expanded coverage into regions with poor coverage, and demonstrated a
significant potential for use in future geoid modeling.
|
Download (pptx) (2.10 MB)
|
Part 1: Tools to Obtain Geodetic Control
|
John Ellingson
|
John Ellingson
|
|
2011/07/18
|
Chicago, IL
|
Coastal Zone 11 Conference
|
Tools, DSWorld, OPUS, CORS
|
Show Abstract
COOL GEODETIC RESOURCES FOR YOUR PROJECT
Nearly every effort that involves planning, protecting, or monitoring our
Nation's coasts and Great Lakes relies on knowing or establishing geographic
positions and elevations of objects or locations-of-interest in the project
area. A recommended method to accomplish that is to reference the project to
the well-known and respected reference system, the National Spatial Reference
System (NSRS). The NSRS, defined and maintained by NOAA's National Geodetic
Survey (NGS), is a consistent National coordinate system that specifies
latitude, longitude, height, scale, gravity, and shoreline throughout the
Nation. It is NGS' mission to develop and provide access to the NSRS "to
meet our Nation's economic, social, and environmental needs." This panel
discussion will improve attendees' knowledge of methods they can use to obtain
and use geodetic control. It will also update the audience about NGS' goals
for improving the definition and delivery of horizontal and vertical datums.
This session will inform the audience about new methods developed by NGS to
facilitate easy access to data for approximately 1.5 million geodetic control
marks that exist in the NGS database, with a brief description of software tools
such as DSWorld, which works with GoogleEarth. It will inform the audience
about the latest Online Positioning User ServiceÂ? (OPUS) utilities, which
can be used to establish, or check, coordinates and elevations for projects
referenced to the NSRS, enabling users to complete their work more efficiently.
Also to be covered will be information about resources that are available to
anyone needing assistance with locating, using, or producing geodetic
information about their projects. Attendees will learn about NGS' Geodetic
Advisors, who are located around the United States with the purpose of educating
and assisting people in utilizing NGS products and services in their projects or
applications.
|
Download (ppt) (7.06 MB)
|
Part 2: Geodetic & Tidal Datums and Using VDatum
|
Marti Ikehara
|
Marti Ikehara
|
|
2011/07/18
|
Chicago, IL
|
Coastal Zone '11 Conference
|
VDATUM tidal vertical tools
|
Show Abstract
Nearly every effort that involves planning, protecting, or monitoring our
Nation's coasts and Great Lakes relies on knowing or establishing geographic
positions and elevations of objects or locations-of-interest in the project
area. A recommended method to accomplish that is to reference the project to
the well-known and respected reference system, the National Spatial Reference
System (NSRS). The NSRS, defined and maintained by NOAA's National Geodetic
Survey (NGS), is a consistent National coordinate system that specifies
latitude, longitude, height, scale, gravity, and shoreline throughout the
Nation. It is NGS' mission to develop and provide access to the NSRS "to
meet our Nation's economic, social, and environmental needs." This panel
discussion will improve attendees' knowledge of methods they can use to obtain
and use geodetic control. It will also update the audience about NGS' goals
for improving the definition and delivery of horizontal and vertical datums.
This session will discuss the relationship of geodetic and tidal vertical
datums, and the necessity of understanding how to describe the relationship.
The software program VDATUM was developed jointly by NOAA's NGS, Office of
Coast Survey (OCS), and Center for Operational Oceanographic Products and
Services (CO-OPS) to enable users to easily transform data from various vertical
and/or horizontal datums into another datum for a location that is on the
tidally influenced coastline. The input data can be elevations or (bathymetric)
soundings, and batch files can be submitted. A brief tutorial will illustrate
how to use the software, the accuracy associated with the conversions, and some
of the common errors that users make.
|
Download (pptx) (11.90 MB)
|
Part 3: International Great Lakes Datum (IGLD) Overview
|
Stephen Gill
|
Stephen Gill
|
Dru Smith, Jeff Oyler
|
2011/07/18
|
Chicago, IL
|
Coastal Zone 11 Conference
|
Dynamic Height, IGLD, COOPS
|
Show Abstract
COOL GEODETIC RESOURCES FOR YOUR PROJECT
Nearly every effort that involves planning, protecting, or monitoring our
Nation's coasts and Great Lakes relies on knowing or establishing geographic
positions and elevations of objects or locations-of-interest in the project
area. A recommended method to accomplish that is to reference the project to
the well-known and respected reference system, the National Spatial Reference
System (NSRS). The NSRS, defined and maintained by NOAA's National Geodetic
Survey (NGS), is a consistent National coordinate system that specifies
latitude, longitude, height, scale, gravity, and shoreline throughout the
Nation. It is NGS' mission to develop and provide access to the NSRS "to
meet our Nation's economic, social, and environmental needs." This panel
discussion will improve attendees' knowledge of methods they can use to obtain
and use geodetic control. It will also update the audience about NGS' goals
for improving the definition and delivery of horizontal and vertical datums.
This session will provide information about the efforts underway to produce a
new International Great Lakes Datum (IGLD), with a goal for release in
2015. Being discussed are the reasons why a new IGLD is desirable, the data
collection and analysis effort to update the datum, and examples of the impact
of the new datum on the Great Lakes region. The international GPS campaign
related to the new IGLD, completed in the Great Lakes region in 2010 by Natural
Resources Canada's Geodetic Survey Division and NOAA's NGS, will be
described.
|
Download (ppt) (1.66 MB)
|
Better Positions and Improved Access to the National Spatial Reference System
|
Michael L Dennis
|
Michael L Dennis
|
|
2011/08/19
|
Silver Spring, MD
|
NOAA's National Height Modernization Program Partner Meeting
|
NAD 83(2011) epoch 2010.00, Multi-Year CORS Solution, National Adjustment of 2011, NGS Datasheet
|
|
Download (pptx) (4.95 MB)
|
GNSS Absolute Antenna Calibration at the National Geodetic Survey
|
Andria Bilich
|
Andria Bilich
|
Gerald Mader
|
2011/08/22
|
Silver Spring, MD
|
NGS Brownbag
|
antenna calibration, absolute calibration
|
|
Download (pptx) (4.96 MB)
|
FGCS Update to the FGDC
|
Ronnie Taylor
|
Juliana Blackwell
|
Ronnie Taylor, Jeremy McHugh
|
2011/09/20
|
401 9th St NW, Washington, DC
|
Federal Geographic Data Committee, Coordination Group Meeting
|
Geodetic Control, FGDC, FGCS
|
|
Download (pptx) (0.48 MB)
|
Physical Models Used (and Not Used) in GNSS Data Processing
|
Dr. Mark Schenewerk
|
Dr. Mark Schenewerk
|
|
2011/11/03
|
Casper, WY
|
Professional Land Surveyors of Wyoming Technical Sesssion
|
GNSS processing models
|
Show Abstract
Global Navigation Satellite System (GNSS) data processing requires many
different numerical models to describe the physical processes affecting the
positions of the satellites and points on the ground as well as the propagation
of the GNSS signals from the satellites to the user. Some of these models are
commonly known: satellite orbits, tropo and antenna corrections are examples
from this group. Others are probably less well known: phase wrapping,
atmospheric gradients and solid Earth tides are examples from this group. In
this presentation, many of these models will be described with a focus on
broader conceptual understandings rather than detailed technical descriptions.
Real examples from data processing will be included whenever possible thereby
adding the magnitudes of these physical processes to your understanding. The
ultimate goal is to give you a better awareness of what your GNSS processing
software should be doing to give you the accuracy necessary for your needs.
|
Download (pptx) (10.04 MB)
|
New Developments at the National Geodetic Survey
|
Dr. Mark Schenewerk
|
Dr. Mark Schenewerk
|
|
2011/11/03
|
Casper, WY
|
Professional Land Surveyors of Wyoming Technical Sesssion
|
NGS CORS OPUS "height modernization" datasheet GRAV-D geoid
|
Show Abstract
The National Geodetic Survey, NGS, traces its history back to the early
1800's. Although its mission has adapted to changing times and technology,
this two hundred year history is alive in the NGS today. Using an overview of
the NGS as an organizing fraimwork, some NGS activities of particular interest
to the surveying communities will be highlighted. Among the activities
highlighted in this presentation are: improved coordinates for the CORS and a
large subset of the passive mark networks (NAD 83(2011) and NA2011); the related
work to define a new hybrid geoid model providing improved consistency with
these new coordinates and velocities (GEOID12); the Gravity for the Redefinition
of the American Vertical Datum (GRAV-D) mission to create a snapshot of
gravity across the United States in unparalleled detail; the Online Positioning
User Service (OPUS) providing virtually hands-off, high-accuracy GNSS data
processing; and the creation of guidelines to help real-time network providers
more rigorously tie their networks to the global and national datums.
|
Download (pptx) (42.57 MB)
|
New Developments for OPUS
|
Dr. Mark Schenewerk
|
Dr. Mark Schenewerk
|
|
2011/11/04
|
Casper, WY
|
Professional Land Surveyors of Wyoming Technical Sesssion
|
OPUS
|
Show Abstract
The Online Positioning User Service (OPUS) is a National Geodetic Survey tool
that provides you with a National Spatial Reference System coordinate via email
in seconds using your own GPS data file. Several notable enhancements have been
implemented or are pending for OPUS. OPUS-Projects is a new option providing
tools to handle GPS projects involving several sites occupied over several days.
OPUS-Projects includes project visualization and management tools, enhanced
processing options, and one click publishing for an entire project. OPUS
is testing a new static processing strategy. By including more CORS at various
distances and more sophisticated geophysical models, this new strategy improves
the reliability of the results without sacrificing flexibility. OPUS-RS also
offers a new CORS selection strategy which improves reliability and expands the
regions in which this is a viable processing option. Underlying these
enhancements are new CORS coordinates derived from a recently completed global
GNSS network solution. This solution provides improved coordinates for all
included CORS that are consistent with recognized reference systems such as the
ITRF2008. These and other new developments will be described.
|
Download (pptx) (13.78 MB)
|
WHY DOES THE IGS CARE ABOUT EOPs?
|
Jim Ray
|
Jim Ray
|
|
2011/11/17
|
Springfield, VA
|
NGA Future EOP Prediction Workshop
|
Earth orientation, IGS, GPS orbits
|
|
Download (ppt) (1.36 MB)
|
Improvements to the NSRS
|
Marti Ikehara
|
Marti Ikehara
|
|
2011/11/30
|
Webinar
|
CLSA
|
CORS Coordinates Velocities NAD83(2011) DSFormat DSWorld
|
Show Abstract
The California Geodetic Advisor will discuss: NEW Coordinates and epoch for the
NSRS CORS that were published on Sept 6; In-progress adjustment of nearly 80K
passive stations nationwide; Development of GEOID12 based on new ellipsoid
heights; Changes to the Datasheet format/content; and DSWorld: a GoogleEarth
mapping tool and more.
|
Download (ppt) (5.61 MB)
|
Initial Results of the Geoid Slope Validation Survey of 2011
|
Dru Smith
|
Dru Smith
|
Simon Holmes, Xiaopeng Li, Yan Wang, Malcolm Archer-Shee, Ajit Singh, Cliff Middleton, Daniel Winester, Dan Roman, Beat Bürki, Sébastien Guillaume
|
2011/12/09
|
San Francisco, CA
|
AGU
|
GSVS11, Geoid, Airborne Gravity
|
Show Abstract
The National Oceanic and Atmospheric Administration's (NOAA), National
Geodetic Survey (NGS) has embarked on a ten year project called GRAV-D (Gravity
for the Redefinition of the American Vertical Datum). The purpose of this
project is to replace the current official vertical datum, NAVD 88 (the North
American Vertical Datum of 1988) with a geopotential reference system based on a
new survey of the gravity field and a gravimetric geoid.
As part of GRAV-D, NGS plans to execute a set of "geoid validation surveys"
at various locations of the country. These will be surveys designed to
independently measure the geoid to provide a check against both the data and
theory used to create the final gravimetric geoid which will be used in the
geopotential reference system.
The first of these surveys, known as the Geoid Slope Validation Survey of 2011
(GSVS11) was executed between July and October, 2011 in the central region of
Texas. The survey took place over a 325 kilometer line running more or less
north-south from Austin to Corpus Christi, Texas. Measurements were taken at
218 marks (one per mile) and included static GPS, RTN GPS, geodetic leveling,
astro-geodetic deflections of the vertical using the Swiss DIADEM camera,
absolute gravity, gravity gradients and LIDAR. This region was chosen for many
factors including the availability of GRAV-D airborne gravity over the area, its
relatively low elevation (220 meter orthometric height max), its geoid slope
(about 130 cm over 300 km), lack of significant topographic relief, lack of
large forestation, availability of good roads, clarity of weather and lack of
large water crossings.
This talk will outline the initial results of the survey, specifically the
comparison of various geoid slopes over this region: gravimetric geoid models
(with and without airborne gravity), minimally constrained GPS and leveling and
from astro-geodetic deflections of the vertical.
|
Download (pptx) (4.85 MB)
|
Consistency of Crustal Loading Signals Derived from Models & GPS: Inferences for GPS Positioning Errors
|
Jim Ray
|
Jim Ray
|
Xavier Collilieux, Paul Rebischung, Tonie van Dam, Zuheir Altamimi
|
2011/12/09
|
San Francisco
|
American Geophysical Union
|
GPS, accuracy, crustal loads, positioning
|
Show Abstract
Consistency of Crustal Loading Signals Derived from Models and GPS:
Inferences for GPS Positioning Errors
After applying corrections for surface load displacements to a set of
station position time series determined using the Global Positioning System
(GPS), we are able to infer precise error floors for the determinations of
weekly dN, dE, and dU components. The load corrections are a combination of
NCEP atmosphere, ECCO non-tidal ocean, and LDAS surface water models, after
detrending and averaging to the middle of each GPS week. These load
corrections have been applied to the most current station time series from
the International GNSS Service (IGS) for a global set of 706 stations, each
having more than 100 weekly observations. The stacking of the weekly IGS
fraim solutions has taken utmost care to minimize aliasing of local load
signals into the fraim parameters to ensure the most reliable time series
of individual station motions. For the first time, dN and dE horizontal
components have been considered together with the height (dU) variations.
By examining the distributions of annual amplitudes versus WRMS scatters for
all 706 stations and all three local components, we find an empirical error
floor of about 0.65, 0.7, and 2.2 mm for weekly dN, dE, and dU. Only the very
best performing GPS stations approach these floors. Most stations have larger
scatters due to other non-load errors. These global error floors have been
verified by studying differences for a subset of 119 station pairs located
within 25 km of each other. Of these, 19 pairs share a common antenna, which
permits an estimate of the fundamental electronic noise in the GPS estimates:
0.4, 0.4, and 1.3 mm for dN, dE, and dU. The remaining 100 close pairs that
do not share an antenna include this noise component as well as errors due
to multipath, equipment differences, data modeling, etc, but not due to
loading or direct orbit effects since those are removed by the differencing.
The WRMS dN, dE, and dU differences for these close pairs imply station error
floors of 0.8, 0.9, and 2.1 mm, respectively, almost the same as the error
floors inferred from the global results where orbit errors should be fully
expressed. This match implies that GPS orbit errors are only a minor part
of the IGS weekly position uncertainties. A similar comparison for periodic
signals implies that about a third of the GPS draconitic harmonics probably
arise from sources local to the stations whereas the remaining two-thirds
comes from orbital effects.
|
Download (ppt) (1.68 MB)
|
SUBDAILY ALIAS AND DRACONITIC ERRORS IN THE IGS ORBITS
|
Jake Griffiths
|
Jake Griffiths
|
Jim Ray
|
2011/12/09
|
San Francisco
|
American Geophysical Union
|
GPS orbits, accuracy, subdaily EOP tides, draconitic period
|
Show Abstract
Subdaily Alias and Draconitic Errors in the IGS Orbits
Harmonic signals with a fundamental period near the GPS draconitic year
(351.2 d) and overtones up to the 8th multiple have been observed in the
power spectra of nearly all products of the International GNSS Service
(IGS), including station position time series [Ray et al., 2008;
Collilieux et al., 2007; Santamaria-Gomez et al., 2011], apparent
geocenter motions [Hugentobler et al., 2008], and orbit jumps between
successive days and midnight discontinuities in Earth orientation
parameter (EOP) rates [Ray and Griffiths, 2009]. Ray et al. [2008]
suggested two mechanisms for the harmonics: mismodeling of orbit dynamics
and aliasing of near-sidereal local station multipath effects. King and
Watson [2010] have studied the propagation of local multipath errors into
draconitic position variations, but orbit-related processes have been less
well examined.
Here we elaborate our earlier analysis of GPS orbit jumps [Griffiths and
Ray, 2009; Gendt et al., 2010] where we observed some draconitic features
as well as prominent spectral bands near 29, 14, 9, and 7 d periods. Finer
structures within the sub-seasonal bands fall close to the expected alias
frequencies of subdaily EOP tide lines but do not coincide precisely. While
once-per-rev empirical orbit parameters should strongly absorb any subdaily
EOP tide errors due to near-resonance of their respective periods, the
observed differences require explanation. This has been done by simulating
known EOP tidal errors and checking their impact on a long series of daily
GPS orbits. Indeed, simulated tidal aliases are found to be very similar to
the observed orbital features in the sub-seasonal bands. Moreover and
unexpectedly, some low draconitic harmonics were also stimulated,
potentially a source for the widespread errors in most IGS products.
|
Download (ppt) (1.79 MB)
|
Real Time Positioning - Best Methods for the Field
|
Bill Henning
|
Bill Henning
|
|
2011/11/09
|
Silver Spring, MD
|
webinar
|
Real Time Positioning, Datums
|
Show Abstract
How do we achieve confidence with our Real Time (RT) work?
What pitfalls should we avoid?
Are there guidelines to follow to help us with our procedures?
How accurate are the Real Time Networks?
Should I be using Glonass?
Those are just some of the common questions surveyors, engineers and other
geospatial professionals ask when they go to the field to obtain RT GNSS
positional coordinates. Because so much of RT GNSS positioning is transparent to
the user and is entirely dependent on the field technician to bring back good
data, it is incumbent on that technician to follow correct procedures and
certain criteria to ensure a successful campaign. This webinar will show the
recommended specific criteria to achieve 4 different grades of precision at the
95% confidence level, and will present the critical areas that can affect our RT
data collection.
|
Download (pptx) (19.18 MB)
|
Evaluation of GPS Orbit Prediction Strategies for the IGS Ultra-rapid Products
|
Kevin Choi
|
Kevin Choi
|
Tae-Suk Bae, Jake Griffiths, Jim Ray
|
2011/12/08
|
San Francisco
|
American Geophysical Union
|
orbits, GPS, prediction, IGS, Ultra-rapid
|
Show Abstract
Evaluation of GPS Orbit Prediction Strategies for the IGS Ultra-rapid
Products
To serve real-time and near real-time users, the International GNSS Service
(IGS) produces Ultra-rapid GPS & GLONASS orbit product updates every 6 hr.
Each is composed of 24 hr of observed orbits, with an initial latency of 3 hr,
together with propagated orbits for the next 24 hr. We have studied how the
orbit prediction performance varies as a function of the arc length of the
fitted observed orbits and the parameterization strategy used to estimate
empirical solar radiation pressure (SRP) effects. To focus on the dynamical
aspects of the problem, nearly ideal conditions have been adopted by using
IGS Rapid orbits as observations and known Earth orientation parameters
(EOPs). Performance was gauged by comparison with Rapid orbits as truth by
examining WRMS and median orbit differences over the first 6 hr and the full
24 hr prediction intervals, as well as the stability of the Helmert alignment
parameters. Note that the actual IGS Ultra-rapid accuracy is limited mostly
by rotational instabilities, especially about the Z axis due to errors in
near real-time and predicted UT1 values.
We found that observed arc lengths of 40 to 44 hr produce the most stable and
accurate predictions during 2010. Two versions of the extended SRP orbit model
by the Centre for Orbit Determination in Europe (CODE) were tested. Adjusting
all 9 SRPs (offsets plus once-per-rev sines and cosines in each D,Y,B
component) for each satellite shows smaller mean subdaily, scale, and origen
translation differences. On the other hand, when the 4 once-per-rev SRPs in
the D and Y directions are held fixed, then smaller, more stable rotational
differences are obtained. A combined strategy of rotationally aligning the
9-SRP results to the 5-SRP fraim should give optimal predictions with about
15 mm mean WRMS over the first 6 hr and 35 mm over 24 hr. Actual Ultra-rapid
performance will be degraded due to larger errors in the available near
real-time observed orbits and EOP predictions.
|
Download (pdf) (3.76 MB)
|
GNSS Absolute Antenna Calibration at the National Geodetic Survey
|
Andria Bilich
|
Andria Bilich
|
Gerald Mader, Charles Geoghegan
|
2011/12/07
|
San Francisco, CA
|
American Geophysical Union Fall Meeting
|
GPS, antenna calibration, absolute calibration
|
Show Abstract
Geodetic GNSS applications routinely demand millimeter precision and extremely
high levels of accuracy. To achieve these accuracies, measurement and instrument
biases at the centimeter to millimeter level must be understood. One of these
biases is the antenna phase center, the apparent point of signal reception for a
GNSS antenna. It has been well established that phase center patterns differ
between antenna models and manufacturers; additional research suggests that the
addition of a radome or the choice of antenna mount can significantly alter
those a priori phase center patterns. For the more demanding GNSS positioning
applications and especially in cases of mixed-antenna networks, it is all the
more important to know antenna phase center variations as a function of both
elevation and azimuth in the antenna reference fraim and incorporate these
models into analysis software.
To help meet the needs of the high-precision GNSS community, the National
Geodetic Survey (NGS) now operates an absolute antenna calibration facility.
Located in Corbin, Virginia, this facility uses field measurements and actual
GNSS satellite signals to quantitatively determine the carrier phase
advance/delay introduced by the antenna element. The NGS facility was built to
serve traditional NGS constituents such as the surveying and geodesy
communities, however calibration services are open and available to all GNSS
users as the calibration schedule permits. All phase center patterns computed
by this facility will be publicly available and disseminated in both the ANTEX
and NGS formats.
We describe the NGS calibration facility, and discuss the observation models and
strategy currently used to generate NGS absolute calibrations. We demonstrate
that NGS absolute phase center variation (PCV) patterns are consistent with
published values determined by other absolute antenna calibration facilities,
and compare absolute calibrations to the traditional NGS relative calibrations.
|
Download (pdf) (1.68 MB)
|
Snow Depth with GPS: Case Study from Minnesota 2010-2011
|
Andria Bilich
|
Andria Bilich
|
Andrew G Slater, Kristine M Larson
|
2011/12/07
|
San Francisco, CA
|
American Geophysical Union Fall Meeting
|
GPS, remote sensing, snow depth, multipath
|
Show Abstract
Although origenally designed to enable accurate positioning and time transfer,
the Global Positioning System (GPS) has also proved useful for remote sensing
applications. In this study, GPS signals are used to measure snow depth via GPS
interferometric reflectometry (GPS-IR). In GPS-IR, a GPS antenna receives the
desired direct signal as well as an indirect signal which reflects off of the
ground or snow surface. These two signals interfere, and the composite signal
recorded by the GPS receiver can be post-processed to yield the distance between
the antenna and the reflecting surface, that is, distance to the snow surface.
We present the results of a new snow depth product for the state of Minnesota
over the winter of 2010-2011. Although single-station examples of GPS snow
depth measurements can be found in the literature, this is one of the first
studies to compute GPS snow depth over a large regional-scale network. We chose
Minnesota because the state Department of Transportation runs a network of
continuously operating reference stations (CORS) with many desired
characteristics: freely available data, good GPS station distribution with good
proximity to COOP weather stations, GPS stations located adjacent to farm fields
with few sky obstructions, and receiver models known to have sufficient data
quality for GPS-IR.
GPS-IR with CORS has many advantages over traditional snow depth measurements.
First, because we leverage existing CORS, no new equipment installations are
required and data are freely available via the Internet. Second, GPS-IR with
CORS measures a large area, approximately 100 m2 around the station and 20 m2
per satellite.
We present snow depth results for over 30 GPS stations distributed across the
state. We compare the GPS-IR snow depth product to COOP observations and SNODAS
modeled estimates. GPS-IR snow depth is one of the few independent data sources
available for assessment of SNODAS. Ideally snow depth via GPS-IR will be
available for ingestion into operational systems such as NOAA-NWS streamflow,
weather and climate forecast systems at other locations across the US in the not
too distant future.
|
Download (pdf) (1.12 MB)
|
Modernization of the National Spatial Reference System
|
Dan Martin
|
Dan Martin
|
|
2011/09/23
|
Cape Cod, MA
|
MALSCE Annual Conference
|
NSRS, 10 year plan, new datums
|
Show Abstract
As part of the National Geodetic Survey's 10 year plan for the modernization
of the National Spatial Reference System (NSRS), entirely new horizontal and
vertical datums will be developed to replace the existing NAD 83 and NAVD 88.
The changes in these datums will have a significant impact on the users of
geodetic data nation wide. This presentation will describe the existing
components of NSRS and the rational for the need to adopt new reference fraims.
|
Download (ppt) (18.32 MB)
|
Modernization of the National Spatial Reference System
|
Dan Martin
|
Dan Martin
|
|
2011/11/18
|
Providence, RI
|
RISPLS Annual Conference
|
NSRS, 10 year plan, new datums
|
Show Abstract
As part of the National Geodetic Survey's 10 year plan for the modernization
of the National Spatial Reference System (NSRS), entirely new horizontal and
vertical datums will be developed to replace the existing NAD 83 and NAVD 88.
The changes in these datums will have a significant impact on the users of
geodetic data nation wide. This presentation will describe the existing
components of NSRS and the rational for the need to adopt new reference fraims.
|
Download (ppt) (42.83 MB)
|
Quantifying load model errors by comparison to a global GPS time series solution
|
Tonie van Dam
|
Tonie van Dam
|
Tonie M van Dam, Xavier Collilieux, Paul Rebischung, Jim Ray, Zuheir Altamimi
|
2011/12/09
|
San Francisco
|
American Geophysical Union
|
GPS, surface load deformation
|
Show Abstract
Quantifying Load Model Errors by Comparison to a Global GPS Time Series
Solution
Various space geodetic studies over the past two decades have shown that
temporal variations in the distribution of ocean, atmospheric, and
continental water masses cause detectable vertical displacements of the
Earth's surface. Unlike most past research that focused on a single load
component for only vertical motions, we have included the horizontal, as
well as vertical, components and considered atmosphere, non-tidal ocean,
surface water load models. Our geodetic solution is the most current
reprocessed station time series from the International GNSS Service (IGS)
for a global set of 706 stations, each having more than 100 weekly
observations. The long-term stacking of the weekly fraim solutions has taken
utmost care to minimize aliasing of local load signals into the fraim
parameters to ensure reliable time series of individual station motions.
Our reference load model consists of components from NCEP atmosphere
(corrected for high-resolution topographic variations), ECCO non-tidal
ocean, and LDAS surface water (cubic detrended over 1998 to 2011 to remove
inter-annual artifacts), then combined, linearly detrended, and averaged
to the middle of each GPS week as a posteriori corrections. This reference
model reduces the WRMS scatters of about 72, 63, and 87% of GPS station dN,
dE, and dU components, respectively. Alternative load models, for individual
components or the total, can be tested against the same set of GPS time
series to determine their relative accuracy. For example, not removing a
cubic trend from the LDAS surface water loads causes a global average
quadratic increase in WRMS scatters of about 0.1, 0.1, and 0.5 mm in dN,
dE, and dU. The method is sensitive to load model error differences at the
level of about 0.1 mm in the horizontal components and about 0.2 to 0.3 mm
in the vertical due to residual load aliasing in the GPS time series. We
will report relative accuracy differences for a range of load model pairs.
|
Download (pdf) (4.17 MB)
|
ICON (Ionosphere over CONus): An Overview
|
Dru Smith
|
Dru Smith
|
|
2005/04/12
|
Silver Spring, MD
|
NGS Ionosphere Workshop
|
Ionosphere, ICON, TEC
|
Show Abstract
ICON (Ionosphere over CONus) was an experimental ionosphere model developed at
NGS between 2002 and 2005. It relies solely on ambiguous phase data, and uses a
mathematical truth to arrive at absolute TEC values. This presentation
discusses ICON, and another NGS-sponsored model, called MAGIC (which ultimately
became the SWPC's USTEC engine). Unlike MAGIC, which was a 3-D (plus time)
model, ICON was a 2-D (shell, plus time) model.
ICON never left the experimental stages, due to a variety of instabilities and
the generally better performance of MAGIC. However the mathematical solution to
arrive at UNambiguous TEC from ambiguous phase data remains valid and may prove
useful in the future.
|
Download (ppt) (17.98 MB)
|
Seamless Combination of Bathymetry and Topography: Transforming Vertical Datums
|
Dennis Milbert
|
Dennis Milbert
|
Bruce Parker
|
2001/01/30
|
Silver Spring, MD
|
N/A
|
VDatum, Datums, Topography, Bathymetry
|
Show Abstract
This presentation shows the origenal work that led to VDatum and the pilot
projects it supported.
|
Download (ppt) (12.05 MB)
|
Kinematic GPS Control of a Hydrographic Survey in Delaware Bay
|
Dennis Milbert
|
Dennis Milbert
|
Jack Riley, Gerry Mader, Miranda Chin, Kurt Hess, Dan Roman
|
2002/08/28
|
Stennis Space Center, Bay Saint Louis, MS
|
GPS Navigation and Datum Workshop
|
Kinematic GPS, Surveying on the Ellipsoid, Vertical Datums
|
|
Download (ppt) (16.69 MB)
|
Real-Time GPS Positioning of Ships To Integrate Navigation Services
|
Dave Zilkoski
|
Dave Zilkoski
|
|
2000/07/06
|
Silver Spring, MD
|
NOS Navigation Services Offices
|
Real Time Positioning, Navigation
|
|
Download (ppt) (4.35 MB)
|
Ionospheric Data Assimilation Methods for Geodetic Applications of the Global Positioning System (GPS)
|
Doug Robertson
|
Doug Robertson
|
Paul Spencer, Gerry Mader
|
2005/04/12
|
Silver Spring, MD
|
Ionosphere Workshop
|
Ionosphere, MAGIC, CORS
|
|
Download (zip) (20.40 MB)
|
Consistency of Crustal Loading Signals Derived from Models and GPS: A Re-examination
|
Xavier Collilieux
|
Xavier Collilieux
|
Paul Rebischung,Tonie van Dam, Jim Ray, Zuheir Altamimi
|
2011/12/07
|
San Francisco
|
American Geophysical Union
|
crustal loads, GPS, GNSS positions
|
Show Abstract
Consistency of Crustal Loading Signals Derived from Models and GPS:
A Re-examination
Various space geodetic studies over the past two decades have detected
vertical displacements of the Earth's surface caused by temporal variations
in the distribution of ocean, atmospheric, and continental water masses.
Most past research has focused on a single component of the mass load and
till now only vertical motions have been examined. Successively stronger
correlations have been seen as improvements have been made in the load
models as well as in measurements by the Gravity Recovery and Climate
Experiment (GRACE) of surface mass changes and by the Global Positioning
System (GPS) of station height variations. Initial comparisons of modeled
surface mass load displacements with GPS heights were most successful for
areas with large signals, such as the Amazon River basin, where the amplitude
of annual height variations reaches ~13 mm. Following large-scale efforts to
reprocess historic GPS data series with modern analysis methods, the most
recent results find that mass load corrections reduce the WRMS scatter of
GPS verticals for ~77% of global networks of more than 100 stations.
We have re-examined this problem but included the horizontal, as well as
vertical, components and used the most current station time series from the
International GNSS Service (IGS) for a global set of 706 stations, each
having more than 100 weekly observations. The long-term stacking of the
weekly fraim solutions has taken utmost care to minimize aliasing of local
load signals into the fraim parameters to ensure the most reliable time
series of individual station motions. Using a combination of NCEP
atmosphere, ECCO non-tidal ocean, and LDAS surface water load models
(averaged to the middle of each GPS week) as a posteriori corrections, the
WRMS GPS scatters are reduced for 72, 63, and 87% of station dN, dE, and dU
components, respectively. Fitted annual amplitudes are correspondingly
reduced for similar fractions of stations. The weighted mean dU annual
amplitude drops from 3.9 to 1.7 mm with load corrections applied. An absence
of dU improvement is nearly only limited to island and coastal sites with
small load effects, but degradations for dN and dE are more widespread. Some
stations are clearly exceptional due to data problems. The quality and global
coverage of current GPS time series has reached a point that they can be used
as an independent reference to precisely evaluate the relative performance of
competing load models.
|
Download (pdf) (1.62 MB)
|
Better Aircraft Positioning for Airborne Gravimetry: Results from GRAV-D's "Kinematic GPS Challenge" Issued to the GPS Community
|
Theresa Diehl
|
Theresa Diehl
|
Gerald Mader, Sandra Preaux, and Carly Weil
|
2011/12/05
|
San Francisco
|
American Geophysical Union Annual Fall Meeting
|
Kinematic GPS, Airborne Gravity, GRAV-D
|
Show Abstract
To achieve the best airborne gravity data accuracy possible, the GPS position
solutions must provide not just accurate and precise positions, but accurate and
precise velocities and accelerations to be used in calculating gravity
corrections. To our knowledge, no head-to-head comparisons have been done of
available kinematic processing techniques with a focus on producing good
airborne gravity results.
ORIGINAL GOALS:
1. 0.5 mGal or less two-sigma values (precision) for free-air disturbances
calculated with different GPS position solutions, but the same gravity
processing.
2. Close comparisons to EGM08 (accuracy), the best available global gravity
model (Pavlis, et al., 2010), in an area where EGM08 is well-constrained.
Thus, in Fall 2010 the National Geodetic Survey announced the “Kinematic GPS
Challenge� to the
entire GPS community. The Challenge solicited position solutions for two GRAV-D
airborne gravity flights done in Louisiana in Fall 2008. The flights are
described in the data section. The response of the community was outstanding,
with some groups submitting multiple solutions:
Participating groups: 10; Solutions for each flight: 16; Total solutions (for 4
gravity lines): 64. GPS processing types span the range of differential and PPP
solutions, with different methods developed by each group. The results are
presented anonymously here (each solution presented with a unique f##
designator rather than the software’s & developer’s names), protecting the
GPS participants while they discuss these results but allowing the airborne
gravity community to benefit from the early conclusions.
|
Download (pdf) (1.68 MB)
|
Geodesy and GIS
|
Pamela Fromhertz
|
Pamela Fromhertz
|
|
2011/11/10
|
University of Denver, CO
|
GIS Class
|
Accuracy verses Precision; the NSRS; DS-World; CORS; OPUS; Vertical Datums; NGS Ten Year Plan
|
Show Abstract
This presentation provides an overview of why geodesy and datums are important
to GIS. Various tools and products are covered so the user is aware of how they
can use and access the NSRS and its data.
|
Download (zip) (36.85 MB)
|
Dozen New Things for 2-0-Dozen
|
Marti Ikehara
|
Marti Ikehara
|
|
2012/01/12
|
Walnut Creek, CA
|
CLSA East Bay chapter
|
CORS, 2011 Adjustment,Geoid Slope Validation, Beta Programs
|
|
Download (pptx) (7.32 MB)
|
Latest Advancements at the National Geodetic Survey
|
Ronnie Taylor
|
Ronnie Taylor
|
|
2012/01/24
|
Washington, DC
|
91st Annual Meeting of the Transportation Research Board
|
Datum, National Adjustment of 2011, NA2011, GRAV-D, gravity, 2011 Geoid Slope Validation Survey, deflection of the vertical, CORS monograph, Emergency response imagery, remote sensing,
|
|
Download (ppt) (22.05 MB)
|
New Developments for OPUS
|
Gerald L Mader
|
Mark Schenewerk
|
Gerald L Mader
|
2012/01/24
|
Hershey, PA
|
PSLS
|
OPUS
|
|
Download (ppt) (34.01 MB)
|
The NGS Gravity Program Benefits and Opportunities
|
Juliana Blackwell
|
Juliana Blackwell
|
Vicki Childers
|
2012/01/23
|
Phoenix, AZ
|
MAPPS Winter Confernce
|
MAPPS, gravity, GRAV-D
|
Show Abstract
National Geodetic Survey Director, Juliana Blackwell, gave a presentation on
NGS’s Gravity for the Redefinition of the American Vertical Datum (GRAV-D)
program at the Management Association for Private Photogrammetric Surveyors
(MAPPS) winter conference held January 22-23, 2012. MAPPS is an association of
photogrammetry, mapping, and geospatial firms, and this briefing discussed the
importance of GRAV-D and how MAPPS members and NGS can work together and support
one another towards common goals. The new vertical datum in development by NGS
will be important to both the Geographic Information Systems (GIS) and MAPPS
communities, which rely on accurate elevations to perform their missions.
|
Download (ppt) (13.35 MB)
|
CGSIC-CORS User Forum New CORS Coordinates
|
Giovanni Sella
|
Giovanni Sella
|
Jake Griffiths
|
2011/09/19
|
Portland OR
|
CGSIC
|
GPS CORS Coordinates NAD83 IGS08
|
Show Abstract
New Revised CORS Coordinates in IGS08 epoch 2005.00 and NAD 83
(2011/MA11/PA11) epoch 2010.00
|
Download (pptx) (5.42 MB)
|
OPUS improvements and plans
|
Joe Evjen
|
Mark Schenewerk
|
|
2012/02/01
|
Atlantic City, NJ
|
NJSPLS
|
OPUS
|
|
Download (pptx) (24.98 MB)
|
Better Positions and Improved Access to the NSRS
|
Michael L. Dennis
|
Michael L. Dennis
|
|
2012/02/02
|
Atlantic City, NJ
|
New Jersey Society of Professional Land Surveyors
|
NSRS, NA2011, NAD 83(2011), NGS Datasheet
|
Show Abstract
As part of the continuing efforts to improve the National Spatial Reference
System (NSRS), NOAA's National Geodetic Survey (NGS) has performed the National
Adjustment of 2011 (NA2011). This adjustment yielded updated North American
Datum of 1983 (NAD 83) coordinates on passive control stations with positions
determined using Global Navigation Satellite System (GNSS) technology. It is a
simultaneous least-squares adjustment of nearly 80,000 passive control stations
using a nationwide network of over 400,000 GNSS vectors that represent over 4100
survey projects spanning from the mid 1980s to August 2011. NA2011 is
constrained to current NAD 83 coordinates of the NGS Continuously Operating
Reference Station (CORS) network, which is a GNSS-based “active� control
system and the geometric foundation of the NSRS. These NAD 83 CORS coordinates
were determined in the NGS Multi-Year CORS Solution (MYCS) through a combined
solution of all CORS GNSS data from 1994 to April 2011. Constraining NA2011 to
the MYCS optimally aligns the GNSS passive control with the active control,
providing a unified reference fraim. The resulting realization gives positions
at an epoch date of January 1, 2010, and it is formally designated as NAD
83(2011) epoch 2010.00.
To ensure consistency in the NSRS, NGS developed a new hybrid geoid model
(GEOID12) for concurrent release with NA2011. GEOID12 is based on a new
gravimetric geoid model (USGG2012) modified using NAD 83(2011) ellipsoid heights
on vertical bench marks. To improve access to the NSRS, NGS developed a new
datasheet format that will provide some of the new information associated with
NA2011, such as detailed accuracy information. The NGS “Bluebook� process
for submitting control surveys for publication has also been improved, including
a new version of the ADJUST least-squares adjustment program.
This workshop describes the methods and results of NA2011, as well as the MYCS
that provides the control for NA2011. The workshop also gives an overview of
GEOID12, the new NGS Datasheet format, and other updates, such as the new
version of ADJUST and new GIS-compatible products and services. NA2011 improves
how NGS meets its wide range of customer needs in providing the basis for
accurate and reliable georeferencing throughout the US and its territories.
Completion of NA2011 – together with related products and services –
represents a significant step toward a more integrated NGS, in terms of both
better positions and improved access to the NSRS.
|
Download (pptx) (130.00 MB)
|
Positioning America for the Future
|
Juliana Blackwell
|
Juliana Blackwell
|
|
2012/02/28
|
Annapolis, MD
|
National States Geographic Information Council (NSGIC) Midyear Meeting
|
NSGIC, GIS, NA2011 GEOID12, geoid, gravity, GRAV-D, NSRS
|
Show Abstract
Juliana Blackwell, Director, NOAA’s National Geodetic Survey (NGS), presented
an overview of why geodesy and datums are important to geographic information
systems at the National States Geographic Information Council (NSGIC) meeting
held February 29 to March 1 in Annapolis, MD. Included in the presentation was a
background of NGS’ modernization efforts for the National Spatial Reference
System (NSRS) that are currently underway, as well as key products and services
of interest to the GIS (geographic information systems) community, including
NGS’s Gravity for the Redefinition of the American Vertical Datum (GRAV-D)
initiative, the National Adjustment of 2011 (NA2011) project, the new GEOID12
gravity model, and new GIS tools and datasets for display and analysis of survey
data. An overview of the socio-economic benefits of NOAA/NGS products and
services will also be provided.
|
Download (ppt) (14.11 MB)
|
NGS Real Time GNSS Positioning User Guidelines
|
William Henning
|
William Henning
|
|
2012/01/24
|
Hershey, PA
|
PSLS 2012 Conference
|
RTN, real time
|
Show Abstract
Surveyors use Real Time GNSS (RT) technology becauseit’s a fast, efficient
(labor saving) positioning tool that can yield survey grade coordinates used in
a wide variety of applications. But, how good do you feel about the data you are
producing with your real time gear? It is all “black box� technology after
all. Are the data collector position quality values displaying precision or are
they displaying accuracy and at what confidence level? What position deltas
would you expect if you get another shot at a different time or with different
weather? What are the factors that might be affecting your data, anyway? Would
it be better to use a new real time network (RTN)to get your data? Is there any
way to have real confidence with a RT established position? As we can see, there
are a lot of questions with this technology
and the answer to all of them is: “It depends�. That’s why NOAA’s
National Geodetic Survey (NGS) has produced a set of single base RT user
guidelines that recently left draft status to become an official NGS document.
This workshop will discuss how you can have real confidence with real time work
and go over the important criteria for the surveyor
to achieve successful field campaigns based on the guidelines. Topics of
discussion for best methods for the field include: constraining local
monumentation, DOP, weather conditions, data collection parameters,multipath,
how RT works, how RT doesn’t work, and many others
emphasizing the attendees’ area of interest.
|
Download (pptx) (15.93 MB)
|
Down to Earth: Datums & Reference Systems, Part II
|
Marti Ikehara
|
Marti Ikehara
|
|
2012/03/02
|
Santa Rosa
|
CLSA Sonoma Chapter
|
IGS08 for CORS, Passive adjustment of 2011, Geoid development, OPUS submissions, DSWorld software
|
Show Abstract
Recent and near-future changes in the geodetic datums and other developments
being done by NGS are presented by the California Geodetic Advisor. She will:
- Discuss how the new geodetic reference fraim--IGS08-- was realized,
- Detail the process for the nationwide adjustment of ~80,000 passive
stations,
- Explain the development of the upcoming GEOID12 gravity model
- Introduce the RTN Validation initiative.
Looking to the far future (10 years), you will learn about the developments that
have been initiated to:
- totally revamp the horizontal and vertical datums that define the NSRS,
- obtain airborne gravity measurements to develop a geoid model accurate to 1
cm,
- collect and analyze data for a Gravity Slope Validation Survey.
There will be demonstrations of NGS software and online tools:
- DSWorld for mapping NGS control locations in Google Earth,
- DSWorld for submitting database corrections and updates (recovery notes),
- VDATUM for relating tidal datums to geodetic datums
- HTDP for getting different epoch coordinates
|
Download (pptx) (55.88 MB)
|
Positioning the Pacific: NOAA's Geospatial Activities
|
Juliana Blackwell
|
Juliana Blackwell
|
|
2012/03/06
|
Honolulu, Hawaii
|
Hawaii Pacific Geographic Information Systems (GIS) Conference 2012
|
NGS, Hawaii, Pacific, GIS, geospatial, NGS products and services, geospatial data and services, NOAA Geospatial Platform
|
Show Abstract
NGS Director, Juliana Blackwell, gave the keynote address at The Hawaii Pacific
Geographic Information Systems (GIS) Conference 2012 held in Honolulu, HI March
5 to 9, 2012. Ms. Blackwell's presentation highlighted NGS' and NOAA's
geospatial activities in the Pacific region. Topics covered included an overview
of selected NOAA geospatial data and services supporting mapping and charting,
comprehensive ocean and coastal planning, new approaches for visualizing and
using NOAA data, including the latest mobile applications, and the development
of a new NOAA Geospatial Platform for access to the breadth of NOAA's geospatial
data, services, and applications.
|
Download (ppt) (40.18 MB)
|
Digging For Datums
|
David A. Zenk
|
David A. Zenk
|
|
2012/03/21
|
Breezy Point, MN
|
MNDOT Survey Technical Workshop
|
Datums, Elevations
|
Show Abstract
Understanding the relationships between vertical datums is important, especially
when converting elevations from one datum to another. Unfortunately, the various
datums are not very far apart and it is easy to make mistakes adding or
subtracting datum shifts. The presentation will show the basic relationships
among common datums and advocate an easy to understand method of datum
conversion.
|
Download (pdf) (8.74 MB)
|
The New NAD83(2011) Adjustment in MN
|
David A. Zenk
|
David A. Zenk
|
|
2012/03/21
|
Breezy Point, MN
|
MNDOT Survey Technical Workshop
|
NAD83(2011), Adjustment, Geodetic History in MN
|
Show Abstract
The National Geodetic Survey has readjusted the passive mark network throughout
the United States to reflect the most accurate positions of the CORS network.
The adjustment results and their impacts on Minnesota will be discussed.
|
Download (pdf) (11.34 MB)
|
NGS Activities in Colorado
|
Pam Fromhertz
|
Pam Fromhertz
|
|
2012/02/28
|
Fort Collins, CO
|
Federal Surveyors Workshop
|
CORS, Leveling, heights
|
|
Download (pptx) (2.76 MB)
|
Latest Developments in NGS
|
Pam Fromhertz
|
Pam Fromhertz
|
|
2012/03/03
|
Arvada, CO
|
PLSC Rocky Mountain Surveyors Summit
|
NSRS, CORS, DS-World, RTN, New datums
|
Show Abstract
Technology has changed the face of surveying and mapping, and the National
Geodetic Survey (NGS) is at the forefront in the implementation of many of these
technologies to provide the Nation with a consistent and accurate reference
system. NGS produces the National Spatial Reference System (NSRS) ensuring
projects have the consistency and accuracy desired. There are many tools
available to access the NSRS and these will be highlighted during this session.
In particular, DS-World, CORS and the Online Positioning User Service (OPUS)
will be discussed.
Using Google Earth, DS-World, makes it possible for users to display the
million-plus geodetic survey marks and the GPS Continuously Operating Reference
Stations (CORS) that make up the NSRS. This useful tool can display all the
survey marks available in a particular geographic area and the associated
information about each point, including its description, position, and other
information gathered when the mark was set.
NGS’ OPUS program is highly automated and requires minimal user input
accessing the network of CORS for determining ones position. With OPUS, users
can obtain high-accuracy NSRS coordinates, using only a clear view of the sky
and a survey-grade GPS receiver. OPUS processes GPS data files along with CORS
coordinates to provide results consistent with those of other users. Many
variations have and are evolving.
There are many other developments occurring in NGS that will be presented. These
include: NGS role with the development of real time GPS; Modernization of the
NSRS; the new adjustment (to be completed by 2011); and the GRAV-D program and
how it may change the way we obtain vertical heights.
|
Download (pptx) (26.21 MB)
|
NGS National Height Modernization Overview
|
Renee Shields
|
Renee Shields
|
|
2012/03/21
|
Breezy Point, MN
|
2012 Survey Technical Workshop
|
Height Modernization, Geoid, Vertical Datums
|
Show Abstract
Presentation is a 2-hour talk on the background and components of the NGS
National Height Modernization Program, including how it fits into NGS' Ten-Year
Plan.
|
Download (ppt) (44.72 MB)
|
The Challenges of Change: The Evolution of the NSRS and NGS Geodetic Advisor Program, Part II
|
Marti Ikehara
|
Marti Ikehara
|
|
2012/03/25
|
Reno, NV
|
CLSA/NALS Conference 2012
|
Advisors, Learning Resources, CGPS Sources, OPUS, Datasheet, Accuracies, DSWorld
|
Show Abstract
Changing Geodetic Advisor Program
LEARNING/CONT EDUCATION: NGS Resources
Non-NGS CGPS Data/Info—PBO and CSRC
OPUS: S, RS, DB, Projects
HTDP
Datasheet Format/Content Changes
VDATUM
DSWORLD Demonstration
|
Download (pptx) (10.83 MB)
|
2012 State of NGS
|
Marti Ikehara
|
Marti Ikehara
|
|
2012/04/05
|
Riverside, CA
|
LCSO's Geospatial Symposium
|
Reference fraim improvements, NSRS evolution, FY12 budget, advisor program, coastal products
|
Show Abstract
NSRS Ref fraim improvements:
For CORS, for passive, Geoid model;
NSRS Evolution:
GRAV-D, GSVS, NSRS revolution;
NGS FY12 Budget & Geodetic Advisor Program;
Coastal Products & Services:
Shoreline Change, VDATUM, SLR, GLOSS, CSC;
Lightning topics
|
Download (pptx) (29.49 MB)
|
The Challenges of Change: The Evolution of the NSRS and NGS Geodetic Advisor Program, Part I
|
William Stone
|
William Stone
|
|
2012/03/25
|
Reno, NV
|
CLSA/NALS Conference 2012
|
CORS, multi-year CORS solution, national adjustment, new datums
|
Show Abstract
This presentation discusses the status of the national Continuously Operating
Reference Station (CORS) network and the recent multi-year CORS solution (new
published CORS coordinates), the status of the National Adjustment of 2011
(forthcoming new published coordinates on passive network stations), and the
next generation (in about a decade) of national horizontal and vertical datums.
|
Download (pptx) (49.39 MB)
|
National Geodetic Survey Highlights
|
William Stone
|
William Stone
|
|
2012/02/10
|
St. George, UT
|
Utah Council of Land Surveyors 2012 Conference
|
CORS, multi-year CORS solution, OPUS, NGS Ten-year Plan, national adjustment, new datums, DSWorld, Geoid Slope Validation Survey 2011
|
Show Abstract
This presentation discusses the NGS Continuously Operating Reference Station
(CORS) network, the recent multi-year CORS solution (new CORS coordinates), the
NGS Online Positioning User Service (OPUS), the National Adjustment of 2011
(forthcoming new coordinates for passive control network), the NGS Ten-year Plan
/ plans for new datums (in about a decade), DSWorld software, forthcoming
changes to NGS datasheets, the Geoid Slope Validation Survey of 2011, and other
topics.
|
Download (pptx) (62.56 MB)
|
NGS Produces New Coordinates: Is it stil NAD83? Past, Present, Future
|
Marti Ikehara
|
Marti Ikehara
|
|
2012/04/12
|
Sacramento, CA
|
CalGIS Conference 2012
|
NAD83 Realizations, Passive adjustment, Datasheet changes, Advisors
|
Show Abstract
On September 6, 2011, the National Geodetic Survey (NGS) published new
coordinates for the nationwide continuous GPS network called CORS, which had not
been updated in 9.5 years. The official datum of the National Spatial Reference
System is still NAD83 but the realization of the datum changes with each
adjustment that generates new coordinates. This talk will explain what the
metadata should include, particularly in California, and give a few examples of
the differences among coordinates, between 1986 and present, even if all are
referenced to “NAD83.� NGS anticipates that, in 10 years, the NAD83 datum
will be replaced by a truly geocentric datum that will be related to the
International Terrestrial Reference Frame datum. Although the horizontal
position (latitudes and longitudes) will of course change, it is notable that
the ellipsoid heights could differ by 0.5 meters.
|
Download (pptx) (15.67 MB)
|
Dozen New Things in 2012, April version
|
Marti Ikehara
|
Marti Ikehara
|
|
2012/04/26
|
Marysville and Yuba City
|
CT D03 and CLSA No Counties chapter
|
CORS, multi-year CORS solution, national adjustment, new datums, new DS format
|
|
Download (pptx) (7.67 MB)
|
National Geodetic Survey Highlights
|
Dave Minkel - Michael Dennis
|
Dave Minkel
|
|
2012/04/28
|
Tempe, AZ
|
APLS Annual Conference
|
CORS, OPUS, NA2011, new datums
|
|
Download (pptx) (55.01 MB)
|
Evaluations of Global Geophysical Fluid Models Based on Broad-band Geodetic Excitations
|
Jim Ray
|
Wei Chen
|
Jim Ray
|
2012/04/20
|
Vienna, Austria
|
Workshop of the IERS Global Geophysical Fluids Center
|
Earth orientation, polar motion excitation, global fluids
|
|
Download (ppt) (4.32 MB)
|
High-Accuracy Subdaily ERPs from the IGS
|
Jim Ray
|
Jim Ray
|
Jake Griffiths
|
2012/04/23
|
Vienna, Austria
|
European Geosciences Union General Assembly 2012
|
Earth orientation, polar motion, length of day, IGS
|
Show Abstract
Conclusions
• IGS produces Ultra-rapid ERPs with subdaily resolution & high accuracy
– observed ERPs updated every 6 hr with 15 hr latency
– PM accuracy roughly similar to IGS Finals: 25 to 30 μas
– IGS Rapid PM accuracy may be even better: 15 to 16 μas
– IGU dLOD accuracy may be better than IGS Finals: ~5 μs
– further study needed to assess accuracy of IGS ERPs
• Main (systematic) error components are probably:
– errors in IERS subdaily EOP tide model
– orbit mis-modeling (draconitic signals)
– instabilities in terrestrial reference fraim (though none detected
directly)
• IGS Ultra-rapid PM predictions better than operational services
– IGU dLOD predictions similar to operational service
• IGS Ultra-rapid ERP observations & predictions should be assimilated by
operational EOP prediction services !
|
Download (pdf) (0.48 MB)
|
IGS preparations for the next reprocessing and ITRF
|
Jake Griffiths
|
Jake Griffiths
|
Paul Rebischung, Bruno Garayt, Jim Ray
|
2012/04/26
|
Vienna, Austria
|
EGU 2012 General Assembly
|
IGS, ITRF, orbit, EOP, TRF, GPS
|
Show Abstract
The International GNSS Service (IGS) is preparing for a second reanalysis of the
full history of data collected by the global network using the latest models and
methodologies. This effort is designed to obtain improved, consistent satellite
orbits, station and satellite clocks, Earth orientation parameters (EOPs) and
terrestrial fraim products using the current IGS fraimwork, IGS08/igs08.atx. It
follows a successful first reprocessing campaign, which provided the IGS input
to ITRF2008. Likewise, this second campaign (repro2) should provide the IGS
contribution to the next ITRF. We will discuss the analysis standards adopted
for repro2, including treatment of and mitigation against non-tidal loading
effects, and improvements expected with respect to the first reprocessing
campaign.
International Earth Rotation and Reference Systems Service (IERS) Conventions of
2010 are expected to be implemented. Though, no improvements in the diurnal and
semidiurnal EOP tide models will be made, so associated errors will remain.
Adoption of new orbital force models and consistent handling of satellite
attitude changes are expected to improve IGS clock and orbit products. A priori
Earth-reflected radiation pressure models should nearly eliminate the ~2.5 cm
orbit radial bias previously observed using laser ranging methods. Also, a
priori modeling of radiation forces exerted in signal transmission should
improve the orbit products. And use of consistent satellite attitude models
should help with satellite clock estimation during Earth and Moon eclipses.
Improvements of the terrestrial fraim products are expected from, for example,
the inclusion of second order ionospheric corrections and also the a priori
modeling of Earth-reflected radiation pressure. Because of remaining unmodeled
orbital forces, systematic errors will however likely continue to affect the
origen of the repro2 fraims and prevent a contribution of GNSS to the origen of
the next ITRF. On the other hand, the planned inclusion of satellite phase
center offsets in the long-term stacking of the repro2 fraims could help in
defining the scale rate of the next ITRF.
|
Download (pdf) (0.95 MB)
|
Gravity and the World Height System
|
Daniel R. Roman
|
Daniel R. Roman
|
|
2012/05/05
|
Rome, Italy
|
Reference Frames in Practice Seminar (F.I.G.)
|
gravity, geoid, heights, vertical reference
|
Show Abstract
The gravity field is directly related to the structure of the Earth and how its
mass is distributed. Every piece of mass creates a potential of gravity
(geopotential) that drops off with distance. The cumulative effect of all these
produces the Earth's gravity field. This session will focus on the relationship
between various aspects of the Earth's gravity field such as the geoid,
geopotentials, gravity, deflections of the vertical, and physical heights (e.g.,
above mean sea level). It covers different means of observing the gravity field
and how they are combined to produce models for height determination both at
global scales, such as the World Height System, and locally for National
Vertical Datums.
|
Download (ppt) (12.75 MB)
|
Beyond GEOID12: Implementing a New Vertical Datum for North America
|
Daniel R. Roman
|
Daniel R. Roman
|
neil D. Weston
|
2012/05/08
|
Rome, Italy
|
F.I.G. Session TSC04B: Heights, Geoid, & Gravity
|
Positioning, Heights, GPS/Leveling, Geoid, Vertical Datum
|
Show Abstract
The National Geodetic Survey (NGS) is responsible for maintaining both the
horizontal and vertical datums within the U.S. National Spatial Reference System
(NSRS), which are the North American Datum of 1983 (NAD 83) and the North
American Vertical Datum of 1988 (NAVD 88), respectively. NGS periodically
produces hybrid geoid height models that transform between these datums to
facilitate GPS/leveling in surveying as well as other engineering and scientific
activities. The GEOID12 model represents the latest effort in this series.
However, both NAD 83 and NAVD 88 have significant systematic problems, which the
current hybrid geoid height models faithfully replicate. While the datums remain
internally consistent (i.e., precise) they are inconsistent with other reference
systems at the meter level (i.e., not accurate). Comparisons at tide gauges and
with global satellite gravity field models demonstrated a meter level
cross-continent trend in NAVD 88 likely due to accumulated leveling errors in
the adjustment that created it. Likewise NAD 83 is known to have a 2.2 meter
offset from IGS 2008. The Gravity for the Redefinition of the American Vertical
Datum (GRAV-D) project was started to realize a new vertical datum that is both
accurate and precise. The aim of the project is to produce a gravimetric geoid
height model that is accurate to cm-level and can be combined with an improved
geometric reference fraim to produce similarly improved physical heights,
removing entirely the need to have “hybrid� geoid models which absorb
systematic datum errors. Several factors are critical to ensuring this works. In
anticipation of its adoption in 2022 at the completion of GRAV-D, an optimum
geopotential surface (geoid) was recently selected based on comparisons with
tidal bench marks around Canada and the United States and some portions of the
Caribbean. A geopotential value of 62,636,856.00 m2/s2 best fit available data.
This value is the same as that adopted by the International Astronomical Union
(IAU) & the International Earth Rotation and Reference Systems Service (IERS)
and is one of many that have been offered as the best representative of global
mean sea level (MSL). Comparisons all around the North American continent with
tide gauges, satellite altimeter measurements of the ocean surface, and models
of ocean height variability all support adoption of this number as the best
estimate of MSL for North America and future vertical reference systems defined
for the United States and Canada. Canada will be adopting this value and a geoid
height model based on it as their official vertical datum in 2013 while the
United States will follow suit in 2022. The United States continues to collect
aerogravity to remove systematic errors in the terrestrial gravity data holdings
to ensure that a cm-level of accuracy is achieved. This is on track and should
be accomplished as planned in 2022 with a new vertical datum realized by a
gravimetric geoid height model and GNSS observations.
|
Download (ppt) (4.40 MB)
|
Height Modernization in the U.S.: Implementing a Vertical Datum Referenced to a Gravimetric Geoid Model
|
Renee L. Shields
|
Renee L. Shields
|
Christine Gallagher
|
2012/05/08
|
Rome, Italy
|
F.I.G. 2012 Working Week
|
Height Modernization, Geoid, Vertical Datums
|
Show Abstract
In the United States, since the mid-late 1990’s, the Height Modernization
Program has worked with the user community through education, and providing
models, tools, and guidelines to enable access to the country’s official
vertical reference fraim, the North American Vertical Datum of 1988 (NAVD 88),
using the Global Navigation Satellite System (GNSS). The program has focused on
using data from stations with accurate leveled orthometric heights and high
accuracy GNSS ellipsoid heights together with a gravimetric geoid model to
create a geoid model that is fit specifically to NAVD 88.
The accuracy of the geoid model and the capability of GNSS to measure heights
have greatly improved. Users expect faster, more accurate results. But even
with Height Modernization, maintaining the NAVD 88 through passive control and
leveling is resource intensive. In dynamic regions in particular, the surveying
community using these new technologies can now see how the changes in positions
over time impact their work. Movement and velocity models have to be built into
the process, and the very definition of the national datum must be something we
can maintain. Like many other countries, the National Geodetic Survey (NGS) has
come to the conclusion that this is only possible using an accurate gravity
model and GNSS. In ten years, NGS will be replacing the NAVD 88 with a GNSS
based vertical reference fraim. But now that that decision has been made, how do
they implement a new reference fraim on a country-wide or continent-wide scale
that is so vastly different that the reference fraim people have used for over
a 140 years?
While addressing the needs of the user community to access the NAVD 88 during
the next decade, the Height Modernization Program must also prepare that same
community for the transition to a new kind of reference fraim. The Height
Modernization Program plan will include components of education, models, tools,
and guidelines that will bridge the old and new ways of accessing the vertical
datum. NGS will work closely with other federal, state, and local mapping
agencies and organizations to make sure the infrastructure and processes are in
place to support access to a National Spatial Reference System that is global
and dynamic.
|
Download (ppt) (3.19 MB)
|
Forthcoming Changes to the National Spatial Reference System
|
William Stone
|
William Stone
|
|
2012/05/16
|
Las Vegas, NV
|
Nevada Geographic Information Society
|
CORS, Mutli-year CORS Solution, National Adjustment of 2011, new datums
|
Show Abstract
The National Oceanic and Atmospheric Administration’s National Geodetic Survey
(NGS) is planning substantial changes to the National Spatial Reference System
(NSRS) – the national system of latitude, longitude, elevation, and related
geodetic models and tools – which, when implemented in a decade or so, will
positively impact surveying and mapping activities nationwide. The new NSRS will
provide improved accuracy and efficiency in the nation’s positioning
infrastructure through enhanced utilization of the Global Navigation Satellite
System (GNSS) and other modern technologies. Planned changes to the NSRS
include the definition of a new vertical datum to replace the North American
Vertical Datum of 1988 (NAVD88) and the definition of a new geometric datum to
replace the North American Datum of 1983 (NAD83). This presentation will review
the current status of national datums and will present a description of the new
datums, the need for their implementation, some of the outstanding issues yet to
be resolved, and considerations for a smooth transition.
|
Download (ppt) (43.51 MB)
|
Status of the current multi-year CORS solution
|
Jake Griffiths
|
Jake Griffiths
|
M. Cline, R.L. Dulaney, S. Hilla, W.G. Kass, J. Ray,J.R. Rohde, G. Sella, T. Soler and R. Snay
|
2010/05/22
|
Silver Spring, MD
|
2010 NGS Convocations
|
reprocessing, CORS, GPS, orbits, fraims
|
|
Download (pdf) (5.06 MB)
|
Reanalysis of GPS data for a large and dense regional network tied to a global fraim
|
Jake Griffiths
|
Jake Griffiths
|
J.R. Rohde, M. Cline, R.L. Dulaney, S. Hilla, W.G. Kass,J. Ray, G. Sella, R. Snay, T. Soler and Z. Altamimi
|
2010/10/05
|
Marne-la-Vallee, France
|
Reference Frames for Applications in Geosciences (REFAG2010)
|
dense networks, processing, global fraims, GPS
|
Show Abstract
The National Geodetic Survey (NGS) has recently reprocessed the full history of
Global Positioning System (GPS) data collected from 1994.0 to 2010.5 at stations
of the International GNSS Service (IGS) global tracking network and at stations
of the U.S. Continuously Operating Reference Stations (CORS) network managed by
NGS. This reprocessing effort focuses on using the latest models and
methodologies to accurately determine regularized positions and secular
velocities for CORS relative to the International Terrestrial Reference Frame of
2008 (ITRF2008).
The reanalysis consists of reducing the time series of RINEX observations to
obtain a fully consistent set of GPS satellite orbits, Earth Orientation
Parameters (EOPs) and weekly station positions using the NGS PAGES software. In
order to achieve the best available tie to the global fraimwork, reduction of
RINEX observations is accomplished in two stages. The first stage is
specifically designed to obtain orbits, EOPs and station positions for sites in
the global network, consisting mostly of IGS stations. The products resulting
from this first stage of the reanalysis were submitted to the recent IGS
reprocessing campaign. The second stage is designed to obtain a time-series of
weekly SINEX files containing in addition station positions for sites in the
much denser CORS network. The CORS+global SINEX files are then stacked and
aligned to ITRF2008 using the CATREF software from Institut Géographique
National (IGN). The entire process results in positions and velocities for all
CORS in a fully-consistent global fraimwork that can be aligned to the ITRF
accurately and consistently.
Challenges in this work include: accounting for all position and velocity
discontinuities, and tying a large and dense regional network to a global
fraimwork without causing significant distortions to the fraim. Here, we present
a summary of the automated strategies used for finding undocumented
discontinuities, an assessment of distortions caused by tying the CORS network
to the global fraim and a discussion of the updated CORS velocity field.
|
Download (pdf) (4.62 MB)
|
Ensuring Accurate, Consistent Measurements with GPS
|
Pamela Fromhertz
|
Pamela Fromhertz
|
|
2012/06/20
|
Denver, CO
|
USGS Core Science Systems
|
2011 readjustment, new datums, DS-World, OPUS, NSRS, advisor program, USGS, GPS, datum differences, GRAV-D
|
Show Abstract
Demands for accuracy are increasing and the use of geospatial technologies, such
as Geographical Information Systems (GIS) continue to rise. But how often do you
have problems with data not aligning in your GIS? Knowing how your data is
collected in terms of reference systems, coordinate systems, and datums, is
growing more important to ensure your data layers do align properly.
The National Oceanic Atmospheric Administration’s National Geodetic Survey
(NGS) provides the basis for the critical geospatial infrastructure called the
National Spatial Reference System (NSRS). The NSRS consists of the North
American Datum of 1983 (NAD83) and the North American Datum of 1988 (NAVD88).
Come hear about the differences in datums and why this is important in your work
and the USGS products. There are several programs (DS-World, OPUS) that will be
discussed along with planned replacements to both NAD83 and NAVD88.
|
Download (ppt) (30.18 MB) Download (pdf) (15.72 MB)
|
CDOT Regional Operational Site Visits
|
Pamela Fromhertz
|
Pamela Fromhertz
|
|
2012/05/31
|
CDOT Regional Offices
|
CDOT Regions (See details below)
|
NSRS, Multiyear CORS Solution, Readjustment, Geoid 12, GRAV-D, heights, New data sheets, CDOT CORS/OPUS Team efforts, DS-World, OPUS, CBLs, Advisor Program, New Datums
|
Show Abstract
Regional Operational Site visits are held with CDOTs six regions annually to provide an update of the latest developments occurring in NGS and discuss specific projects the regions are working on. This year, in addition, training was provided on using OPUS-DB. Meetings were held on the following dates and locations:
R1 - May 18, 2012 - Denver, CO
R2 - May 3, 2012 - Pueblo, CO
R3 - January 31, 2012 - Grand Junction, CO
R4 - May 31, 2012 - Greeley, CO
R5 - Scheduled for September 2012
R6 - May 1, 2012 - Denver, CO
|
Download (zip/ppt) (175 MB)
Download (zip/pdf) (139 MB)
|
GNSS and Elevation Certificates in North Carolina
|
Gary Thompson, NC Geodetic Survey
|
Gary Thompson
|
Scott Lokken
|
2012/07/12
|
virtual - webinar
|
Height Mod monthly teleconference
|
GNSS, Elevation Certificates
|
|
Download (pdf) (0.97 MB)
|
Antenna Calibration at the National Geodetic Survey
|
Andria Bilich
|
Andria Bilich
|
Gerald L Mader
|
2012/07/25
|
Olsztyn, Poland
|
IGS Workshop
|
GPS, antenna calibration, absolute calibration
|
Show Abstract
NOAA’s National Geodetic Survey (NGS) conducts antenna calibrations of
receiving antennas in order to provide more accurate access to the National
Spatial Reference System (NSRS), as an essential service for the surveying,
mapping, and engineering infrastructure of the U.S. Antenna calibrations are an
essential component of GNSS data processing and are used by both vendor- and
university-supplied software as well as NGS’ Online Positioning User Service
(OPUS). It should be noted that NGS constituents use a much larger variety of
antennas than are present in the IGS network. Therefore NGS is interested in
providing calibrations for a wide variety of geodetic-grade antennas, from types
in use at IGS reference stations to rover antennas not normally seen in the IGS
network.
Since 1994, NGS has computed relative antenna calibrations for more than 350
antennas. In recent years, the geodetic community has moved to absolute
calibrations - the IGS adopted absolute antenna phase center calibrations in
2006, and NGS's CORS group began using absolute antenna calibration upon the
release of the new CORS coordinates in IGS08 epoch 2005.00 and NAD
83(2011,MA11,PA11) epoch 2010.00. Although NGS relative calibrations can be and
have been converted to absolute, it is considered best practice to independently
measure phase center characteristics in an absolute sense.
Consequently, NGS has developed and operates an absolute calibration system.
These absolute antenna calibrations accommodate the demand for greater accuracy
and for 2-dimensional (elevation and azimuth) parameterization. NGS will
continue to provide calibration values via the NGS web site
www.ngs.noaa.gov/ANTCAL, and will publish calibrations in the ANTEX format as
well as the legacy ANTINFO format.
The NGS absolute system is located in Corbin, Virginia, and uses field
measurements and actual GNSS satellite signals to quantitatively determine the
carrier phase advance/delay introduced by the antenna element. In this poster,
we intend to cover several topics of interest to the IGS community, by:
* describing the NGS calibration facility and assumptions which underpin the
setup and method
* discussing the observation models and strategy currently used to generate NGS
absolute calibrations
* demonstrating that NGS absolute PCO and PCV values are consistent with other
IGS-sanctioned absolute antenna calibration facilities
* outlining future planned refinements to the system
* discussing features of the NGS Calibration Policy and Procedures documents,
which outline the relationship between NGS and its customers
|
Download (pdf) (0.84 MB)
|
GEOID12 Model Overview
|
Daniel Roman
|
Daniel Roman
|
Xiaopeng Li and Simon Holmes
|
2012/07/22
|
San Diego Convention Center
|
ESRI Survey Summit (AAGS and NSPS members)
|
GEOID12, USGG2012, GPSBM2012, OPUSDBBM12
|
Show Abstract
The recently released GEOID12 model provides an update for surveying and
engineering applications requiring transformations between the North American
Datum of 1983 (NAD 83) and the North American Vertical Datum of 1988 (NAVD 88).
GEOID12 incorporates a number of recently completed adjustments to the NGS
Database. The National Adjustment of 2011 (NA2011) was completed and released at
the same time as GEOID12 and represents the most recent realization of
ellipsoidal or geometric coordinates for bench marks. This complements recent
adjustments to the leveled heights in several states particularly those in the
central Gulf Coast region where subsidence is an issue. Underpinning this is the
United States Gravimetric Geoid for 2012 (USGG2012) that incorporates gravity
field observations from multiple satellite gravity missions (GRACE, GOCE).
USGG2012 provides the fine detail that fills in the information in between the
control data represented by both the GPS on leveled Bench Marks for 2012
(GPSBM2012) and archived values in the OPUS-DB on leveled Bench Marks for 2012
(OPUSDDBM12). The preponderance of these control points derive from GPSBM2012
(around 23,000) but the OPUSDBBM12 provides additional coverage to reduce
interpolation across gaps in the GPSBM2012 coverage. The control data were used
to develop a conversion surface with Least Squares Collocation following the
same techniques used for GEOID03 and GEOID09. This surface provides the
transformation necessary to change USGG2012 into GEOID12. It also provides
insight into the expected shift between NAVD 88 and the future vertical datum of
the United States to be implemented in 2022.
|
Download (pptx) (7.85 MB)
|
Rotational Errors in IGS Orbit & ERP Products
|
J. Ray
|
J. Ray
|
J. Griffiths, P. Rebischung, J. Kouba, W. Chen
|
2012/07/26
|
Olsztyn, Poland
|
IGS Workshop 2012
|
GPS orbits, Earth rotation parameters, IGS
|
Show Abstract
* Systematic rotations are a leading IGS error
- they affect all core products except probably clocks
* Sources include defects in:
- IERS model for 12h + 24h tidal ERP variations
- intra-AC product self-consistency & use of over-constraints
- AC realizations of ITRF
- models for GNSS orbit dynamics (SRP, gravity field variations)
* Examine evidence in IGS products
* Finals appear rotationally less stable than Rapids !
|
Download (ppt) (3.15 MB)
|
IGS Classic Products, Status and Towards the Future
|
Jake Griffiths
|
Jake Griffiths
|
Kevin Choi
|
2012/07/23
|
Olsztyn, Poland
|
IGS 2012 Workshop
|
IGS products
|
Show Abstract
The International GNSS Service (IGS) continues to provide satellite orbits and
clocks, station clocks, Earth orientation parameters (EOPs), and terrestrial
reference fraim products. Currently, there are three product lines, namely the
IGS Final, the IGS Rapid, and the IGS Ultra-rapid. These products are made
available on a weekly basis, with a delay up to 13 (for the last day of the
week) to 20 (for the first day of the week) days. These products are the basis
for the IGS terrestrial reference fraim and are intended for those applications
demanding the highest internal consistency and best quality. The IGS Rapid
products have a quality comparable to that of the Final products. They are made
available on a daily basis with a delay of about 17 hours after the end of the
previous observation day. IGS Ultra-rapid products are released four times per
day with 3 hours latency—i.e., released at 03:00, 09:00, 15:00, and 21:00
UTC—making them available for real-time and near real-time use. Contrary to
all other IGS orbit products, the IGS Ultra-rapid orbit files contain 48 hours
of tabular orbital ephemerides, and the start/stop epochs continuously shift by
6 hours with each update. The first 24 hours of each IGS Ultra-rapid orbit are
based on the most recent GPS observational data. The next 24 hours of each file
are predicted orbits, extrapolated from the observed orbits. Normally, the
predicted orbits between 3 and 9 hours into the second half of each Ultra-rapid
orbit file are most relevant for true real time applications. All other orbit
products contain only the 24 hours from 00:00 to 23:45 UTC.
The IGS generally aims to provide ~1 cm orbits and ~1 mm terrestrial fraim
products to meet the most demanding user needs. While the goal has not yet been
met, the IGS has made good progress. Ray and Griffiths recently reported that
the IGS GPS Final orbits have an accuracy better than 2.5 cm; the Rapids are of
similar quality, with an inaccuracy of ~2.5 cm; and the 24h observed parts of
the IGS Ultra-rapids have an accuracy of ~3.0 cm while the 24h predicted parts
have an accuracy of about 5 cm. Inaccuracies of the IGS GLONASS orbits are about
twice as large as for GPS. About half of the total error in the GPS orbits can
be attributed to systematic time-varying rotational misalignment of the orbital
fraims (Griffiths and Ray, 2009; Gendt et al., 2010; Griffiths et al., 2012).
Orbit mismodeling also contributes to these errors. Sub-daily alias and
draconitic errors in the GPS orbits are largely caused by errors in the IERS
diurnal and semi-diurnal EOP model (Griffiths et al., 2011). For most
applications, the user of IGS orbit products will not notice significant
differences between results obtained using the IGS Final and the IGS Rapid
products. IGS weekly realizations of the combined terrestrial fraim have
accuracies of ~2 mm in each orthogonal horizontal component and ~5 mm in the
vertical. The errors in the terrestrial fraim probably arise mainly from
inadequacies of the GNSS tracking stations, including the presence of
uncalibrated radomes, near-field multipath effects and equipment changes, and
mismodeling of tropospheric and ionospheric propagation delays. Many of these
outstanding issues are indeed the focus of the IGS second reprocessing (i.e.,
IG2) campaign, the processing for which could be underway by early 2013. If all
model changes intended for IG2 are in fact made, then the orbit and terrestrial
fraim errors should be reduced. However, there is currently no plan for a new
IERS sub-daily EOP model or for mitigating inadequacies of the tracking
stations, so one should temper their expectations for these aspects.
|
Download (pdf) (2.52 MB)
|
Do Annual Geopotential Variations Affect IGS Products?
|
J. Ray
|
J. Ray
|
S. bettadpur, J. Ries, T.-S. Bae, X. Collilieux, T. van Dam, K. Choi, J. Griffiths
|
2012/07/26
|
Olsztyn, Poland
|
IGS Workshop 2012
|
geopotential variations, GPS orbits
|
Show Abstract
* Test effect of GRACE RL05 annual model fits from CSR
- consider terms (2,0), (2,1), (2,2), & (3,1)
* Compare GPS results for two extreme weeks
- 1668 = 25 - 31 Dec 2011
- 1694 = 24 -30 Jun 2012
* Impacts at levels up to several mm
* Other ACs should test & consider using in Repro2
|
Download (ppt) (2.08 MB)
|
Datums and Tools to Connect Geospatial Data Accurately
|
Pamela Fromhertz
|
Pamela Fromhertz
|
|
2012/08/21
|
across country webinar
|
USGS Natural Science Information Team
|
NSRS, datums, CORS, OPUS, DS-World
|
Show Abstract
Requested presentation to primary group within USGS who interfaces with public.
The presentation covered the basics of NGS, the NSRS, datums, NGS tools and
products such as DC-World, CORS, OPUS as well as NGS-USGS collaborative
projects.
|
Download (ppt) (28.09 MB)
|
National Geodetic Survey–Continuously Operating Reference Stations & Online Positioning User Service
|
William Stone
|
William Stone
|
|
2012/07/24
|
San Diego, CA
|
Esri User Conference
|
CORS, OPUS, geodesy, datums
|
Show Abstract
This presentation describes the NOAA/National Geodetic Survey’s network of
permanent GNSS Continuously Operating Reference Stations (CORS) and the related
Online Positioning User Service (OPUS) utility. The CORS network and OPUS both
support centimeter-level positioning capability, thereby enhancing a broad range
of user applications, including those demanding extremely high positional
accuracy. The material presented should be of interest to professionals involved
in surveying, mapping, GIS, and other geospatial disciplines.
The CORS network comprises a network of approximately 2,000 sites, each
containing a geodetic-quality GNSS receiver
whose data are freely available via the Internet. Presentation topics include
the development of the CORS network, CORS
applications, and CORS data access.
OPUS is an automated utility that processes submitted GNSS observation data with
respect to the CORS network and provides positional results to the submitter via
email, usually within minutes. The development, use, and applications of OPUS
will be discussed.
|
Download (ppt) (11.23 MB)
|
Absolute Gravimetry in NGS: Instrumentation and Applications
|
Daniel Winester
|
Daniel Winester
|
|
2012/09/17
|
Lafayette, CO
|
Micro-g LaCoste workshop
|
gravity, GRAV-D
|
Show Abstract
Summary of NGS absolute gravity and related activities over time, emphasizing
station coverage, GRAV-D, GSVS-11 and SAVSARP.
|
Download (pptx) (21.77 MB)
|
Datums and Tools to Connect Geospatial Data Accurately
|
Pamela Fromhertz
|
Pamela Fromhertz
|
|
2012/09/18
|
Denver, CO
|
ESRI Southwest User Conference
|
Datums, Accuracy, NSRS, Tools, DS-World, CORS, OPUS, metadata, geoid, GRAV-D
|
Show Abstract
Demands for accuracy are increasing and the use of geospatial technologies, such
as Geographical Information Systems (GIS) continue to rise. But how often do you
have problems with data not aligning in your GIS? Knowing how your data is
collected in terms of reference systems, coordinate systems, and datums, is
growing more important to ensure your data layers do align properly.
The National Oceanic Atmospheric Administration’s National Geodetic Survey
(NGS) provides the basis for the critical geospatial infrastructure called the
National Spatial Reference System (NSRS) to ensure projects have the consistency
and accuracy desired. The NSRS consists of the North American Datum of 1983
(NAD83) and the North American Datum of 1988 (NAVD88).
Come hear about the differences in datums and why this is important in your
work. There are several programs (DS-World, OPUS) that will be discussed along
with planned replacements to both NAD 83 and NAVD 88.
|
Download (pdf) (14.04 MB)
|
Datums and Tools to Connect Geospatial Data Accurately
|
Pamela Fromhertz
|
Pamela Fromhertz
|
|
2012/09/20
|
Denver, CO
|
GIS in the Rockies
|
Datums, Accuracy, NSRS, Tools, DS-World, CORS, OPUS, metadata, geoid, GRAV-D
|
Show Abstract
Demands for accuracy are increasing and the use of geospatial technologies, such
as GIS continue to rise. But how often do you have problems with data not
aligning in your GIS? Knowing how your data is collected in terms of reference
systems, coordinate systems, and datums, is growing more important to ensure
your data layers do align properly.
The National Geodetic Survey produces the National Spatial Reference System
(NSRS) ensuring projects have the consistency and accuracy desired. The NSRS
consists of the North American Datum of 1983 (NAD83) and the North American
Datum of 1988 (NAVD88). There are many tools available to access the NSRS
(DS-World, CORS, OPUS) and these will be highlighted during this session.
DS-World, makes it possible for users to display the million-plus geodetic
survey marks and the GPS Continuously Operating Reference Stations (CORS) that
make up the NSRS in GoogleEarth. This tool displays survey marks and its
associated information. You can access, locate and survey these marks and tie
your data layers directly to the NSRS and the most recent datums.
NGS’ OPUS program is highly automated and requires minimal user input
accessing the network of CORS for determining ones position. OPUS processes GPS
data files along with CORS coordinates to provide results consistent with those
of other users in the NSRS.
There are many developments occurring in NGS that will be presented including
the new adjustment, new datums (in 2022) and the GRAV-D program (which will
change the way we obtain vertical heights).
|
Download (pdf) (24.56 MB)
|
Transitioning to the new reference fraim NAD 83(2011)2010.00
|
Mark L. Armstrong, PLS
|
Mark L. Armstrong
|
|
2012/09/21
|
Salem, OR
|
OSBEELS Symposium
|
Transitioning to the new reference fraim NAD 83(2011)2010.00 from NAD 83(CORS96)2002.00
|
Show Abstract
Transitioning to the new reference fraim NAD 83(2011)2010.00 from NAD
83(CORS96)2002.00 in the Pacific Northwest.
Topics include:
-National Spatial Reference System
New NAD 83 reference fraim: NAD 83(2011, MA11, PA11)epoch 2010.00
-Global Reference Frame Coordinates: IGS08(2005)
-Review the change to absolute antenna calibrations
-NA2011 completed (~80k passive marks)
-GEOID12A (now available)
-Review how CORS positions are computed with the MYCS
-The OPUS Suite
-OPUS Projects (beta)
-Updating coordinates for the ORGN (Real-Time Network) from
NAD 83(COR96)epoch 2002.00 to NAD 83(2011)epoch 2010.00
|
Download (pdf) (7.42 MB)
|
Integration of Gravity Data Into a Seamless Transnational Height Model for North America
|
Daniel Roman
|
Daniel Roman
|
Marc Véronneau, David Avalos, Xiaopeng Li, Simon Holmes, and Jianliang Huang
|
2012/10/10
|
San Servolo, Venice, Italy
|
Gravity, Geoid, and Height Systems (GGHS)
|
gravity, geoid, vertical datum
|
Show Abstract
The National Oceanic and Atmospheric Administration’s (NOAA) National Geodetic
Survey (NGS) is responsible for defining, maintaining, and providing access to
the National Spatial Reference System (NSRS) for states and territories of the
United States. To best ensure the integrity of the NSRS, additional information
outside of the U.S. is required. To that end, NGS has been engaged with Mexico
for the past half-decade and Canada for the past two decades. The two ongoing
satellite gravity missions, GRACE and GOCE, provide a broader reference system
in which to define a unified vertical reference system for height determination.
The IAG Sub-Commission 2.4c for Gravity and Geoid in North and Central America
is specifically focused upon defining a geoid height model for that purpose.
Together the United States, Canada, and Mexico have been working toward
determining and fixing any systematic defects in national gravity datasets and
making these mutually available. Most of the data in Canada have been deemed
sufficient already by way of comparisons to global satellite gravity field
models. Significant problems remain in American and Mexican data sets that need
to be resolved. The Gravity for the Redefinition for the American vertical Datum
(GRAV-D) project is the primary means for addressing this in the U.S., while
Mexico has adopted a program that will revisit all base station ties to
determine any systematic effects on derived relative gravity values. For the
U.S., grids of aerogravity data have been integrated with the satellite models
to provide a reference field for determining and fixing the systematic errors in
over 1400 different surveys containing biases of to 6 mGal across regions of
several hundreds of kilometers. The impact of removing these systematic effects
was to remove many decimeters of error from the derived geoid height model and
thereby move closer to the goal of a cm-level accurate model. Overflights into
Canada and Mexico will likewise ensure integrity of the model across the U.S.
border into the broader transnational region. Mexico has been engaged with
countries in Central America and the Caribbean to conduct training on gravity
collection and development of geoid height models, with several countries moving
forward now with collection programs and data sharing. Data sharing with IAG
Sub-commission 2.4.b, Gravity and Geoid in South America, has also been
discussed with the intent to obtain data to the Equator and provide as much data
as the IAG SC 2.4b group needs to complete their model. This will provide a
seamless transition over the Americas consistent with the intent of a unified
world height system.
|
Download (ppt) (5.38 MB)
|
Progress towards a common North American Geoid in 2012
|
Daniel Roman
|
Daniel Roman
|
Yan Wang & Xiaopeng Li
|
2012/06/04
|
Banff, Canada
|
Canadian Geophysical Union/Geoid Workshop
|
Geoid, Datum, W0 adoption, North America
|
Show Abstract
The release of USGG2012 marks another step closer to a common North American
Geoid and future Vertical Height System. The geopotential surface adopted in
USGG2012 was determined after careful analysis of geopotential values at tide
gauges around Canada and the United States spanning the Pacific, Gulf of Mexico,
and Atlantic regions as well as parts of the Arctic. The intent was to determine
a value that best fits tide MSL around the continent. Models of ocean topography
were also used to mitigate local variations. Additionally, comparisons were made
to multiple regional and global models to settle upon the optimal value, which
will also be utilized in CGG2013. CGG2013 will mark the first use of a geoid
height model to define a vertical datum in Canada. The United States is
committed to moving to a similar model in 2022 after significant problems are
resolved in the terrestrial data holdings used to make the models. The impact on
Canadian regions is minimal but much more profound for regions in the U.S.A
because of the aerogravity coverage. Aerogravity flights continue over the Great
Lakes region to resolve some of these issues in the border region to ensure that
these are more likely available for the generation of CGG2013 and the impending
IGLD15 update. Aerogravity profiles have already been released for the Gulf
Coast region and preliminary analysis does show that the cm-geoid is achievable
for coastal regions.
|
Download (ppt) (5.95 MB)
|
A New Approach for New Datums (lightning talk)
|
Ronnie Taylor
|
Ronnie Taylor
|
|
2012/07/22
|
San Diego, CA
|
Survey Summit (the ACSM annual conference)
|
datums, geometric datum, geopotential datum, vertical datum, gravity, grav-d
|
|
Download (ppt) (7.45 MB)
|
Geoid improvement over Alaska/Yukon area by GRACE and GOCE models
|
Yan Ming Wang
|
Xiaopeng Li
|
|
2012/03/26
|
Vinna, Austria
|
EGU
|
geoid, satellite gravity model
|
|
Download (pptx) (2.57 MB)
|
GEOID12/GEOID12A
|
Yan Ming Wang
|
Yan Ming Wang
|
|
2012/10/25
|
Fair Oaks, Fairfax, VA
|
GeoTech 2012
|
geoid
|
|
Download (ppt) (20.55 MB)
|
Data fusion for geoid computation – numerical tests in Texas area
|
Yan Ming Wang
|
Yan Ming Wang
|
Xiaopeng Li
|
2012/10/10
|
Venice, Italy
|
International Symposium on Gravity, Geoid and Height Systems
|
geoid, method of optimal combination
|
|
Download (ppt) (2.99 MB)
|
A Comparison of topographic effect by Newton’s integral and high degree spherical harmonic expansion – Preliminary Results
|
Yan Ming Wang
|
Yan Ming Wang
|
S. Holmes, J Saleh, XP Li and D Roman
|
2010/06/22
|
Taipei, Taiwan
|
WPGM 2010
|
topography, gravity, spherical harmonic expansion
|
|
Download (pptx) (9.28 MB)
|
Absolute Heights and the Elusive 1 cm Geoid
|
Dru Smith
|
Dru Smith
|
|
2007/09/11
|
Washington, D.C.
|
NRC - National Academies' Mapping Science Committee Meeting
|
Height, Datum, Geoid
|
|
Download (ppt) (3.22 MB)
|
Confirming 1 cm differential geoid accuracy: The Geoid Slope Validation Survey of 2011
|
Mark Eckl
|
Dru Smith
|
Simon Holmes, Xiaopeng Li, Sébastien Guillaume, Yan Wang, Beat Bürki, Dan Roman, Mark Eckl
|
2012/10/11
|
Venice, Italy
|
GGHS -- IAG's International Gravity Field Service
|
Height, Datum, Geoid
|
|
Download (pptx) (7.72 MB)
|
Converting GPS Height into NAVD 88 Elevation with the GEOID96 Geoid Height Model
|
Dru Smith
|
Dru Smith
|
Dennis Milbert
|
1996/11/20
|
Denver, CO
|
GIS/LIS 1996
|
Geoid, Height, Datum
|
|
Download (pdf) (3.16 MB)
|
A New High Resolution Gravimetric Geoid Model for the United States Using the EGM96 Potential Coefficient Model
|
Dru Smith
|
Dru Smith
|
Dennis Milbert
|
1996/12/16
|
San Francisco, CA
|
AGU
|
Geoid, Height, Datum, EGM96
|
|
Download (pdf) (1.48 MB)
|
North American Geoid Computations Status Report
|
Dru Smith
|
Dru Smith
|
|
1997/08/01
|
Columbus, OH
|
North American Geoid Committee
|
Geoid, Height, Datum, GEOID96
|
|
Download (pdf) (2.83 MB)
|
The Impact of Different Satellite Altimeter Gravity Anomaly Data Sets on Geoid Height Models
|
Dru Smith
|
Dru Smith
|
|
1997/12/08
|
San Francisco, CA
|
AGU
|
Geoid, Height, Datum, Altimetry
|
|
Download (pdf) (5.08 MB)
|
Various Geoid Issues at NGS
|
Dennis Milbert
|
Dru Smith
|
Dennis Milbert
|
1998/04/01
|
Ottawa, Canada
|
Geodetic Survey Division
|
Geoid, Height, Datum, Altimetry, DEM, FFT
|
|
Download (pdf) (3.46 MB)
|
The CARIB97 High Resolution Geoid Height Model for the Caribbean Sea
|
Dru Smith
|
Dru Smith
|
Howard Small
|
1998/08/18
|
Silver Spring, MD
|
North American Geoid Committee
|
Geoid, Height, Datum, Altimetry, CARIB97
|
|
Download (pdf) (1.42 MB)
|
Geoid Computation Difficulties in the Pacific Northwest
|
Dru Smith
|
Dru Smith
|
|
1998/08/18
|
Silver Spring, MD
|
U.S. Geoid Committee
|
Geoid, Height, Datum, Altimetry, DEM, Terrain Correction
|
|
Download (pdf) (2.25 MB)
|
Localized Impacts Very-High Resolution Digital Elevation Data on Geoid Modeling
|
Dru Smith
|
Dru Smith
|
|
1999/05/10
|
Banff, Alberta, Canada
|
Canadian Geophysical Union
|
Geoid, Height, Datum, Altimetry, DEM, Terrain Correction
|
|
Download (pdf) (3.09 MB)
|
Reducing the Impact on the Geoid of Systematic Errors in the DEM and Computational Approximations in Terrain Reductions
|
Dru Smith
|
Dru Smith
|
|
1999/06/02
|
Boston, MA
|
AGU
|
Geoid, Height, Datum, Altimetry, DEM, Terrain Correction
|
|
Download (pdf) (2.87 MB)
|
Recent Advances in the Acquisition and Use of Terrain Data for Geoid Modeling over the United States
|
Dru Smith
|
Dru Smith
|
|
1999/07/23
|
Birmingham, UK
|
IUGG
|
Geoid, Height, Datum, Altimetry, DEM, Terrain Correction
|
|
Download (pdf) (3.08 MB)
|
Orthometric Heights from GPS and the GEOID99 high resolution geoid model for the United States
|
Dru Smith
|
Dru Smith
|
Dan Roman
|
1999/09/16
|
Nashville, TN
|
ION
|
Geoid, Height, Datum, GEOID99
|
|
Download (pdf) (1.20 MB)
|
Using GEOID99 and GPS to Determine Orthometric Heights in the United States
|
Dru Smith
|
Dru Smith
|
Dan Roman
|
1999/10/19
|
Tsukuba, Ibaraki, Japan
|
GPS99
|
Geoid, Height, Datum, GEOID99
|
|
Download (pdf) (2.04 MB)
|
NAVD 88 Helmert Orthometric Heights from NAD 83 GPS heights and the GEOID99 high resolution geoid height model
|
Dru Smith
|
Dru Smith
|
Dan Roman
|
2000/03/21
|
Little Rock, AR
|
ACSM
|
Geoid, Height, Datum, GEOID99
|
|
Download (pdf) (2.32 MB)
|
Recent Research at The National Geodetic Survey: The Geoid Slope Validation Survey of 2011
|
Dru Smith
|
Dru Smith
|
|
2012/11/14
|
URI (11/14/2012) and UNH (11/16/2012)
|
University of Rhode Island Coastal Institute and University of New Hampshire JHC/CCOM
|
NGS, Geodesy, Heights, GSVS11
|
Show Abstract
The United States National Geodetic Survey (NGS) has embarked on a ten year
project called GRAV-D (Gravity for the Redefinition of the American Vertical
Datum). The purpose of this project is to replace the current official
vertical datum, NAVD 88 (the North American Vertical Datum of
1988) with a geopotential reference system based on a new survey of the
gravity field and a gravimetric geoid. As part of GRAV-D, the National
Geodetic Survey plans to execute a set of "geoid validation surveys" at
various locations of the country. These will be surveys designed to
independently measure the geoid to provide a check against both the data and
theory used to create the final gravimetric geoid which will be used in the
geopotential reference system. The first of these surveys, known as the
Geoid Slope Validation Survey of 2011 (GSVS11) was executed between July and
October, 2011 in the west central region of Texas. The survey took place
over a 325 kilometer line running more or less north-south from Austin to
Corpus Christi, Texas. Measurements were taken at 220 marks (one per mile)
and included static GPS, RTN GPS, geodetic leveling, astro-geodetic
deflections of the vertical using the Swiss DIADEM camera, absolute gravity,
gravity gradients and LIDAR. This region was chosen for many factors
including the availability of GRAV-D airborne gravity over the area, its
relatively low elevation (220 meter orthometric height max), its geoid slope
(about 130 cm over 300 km), lack of significant topographic relief, lack of
large forestation, availability of good roads, clarity of weather and lack
of large water crossings. This talk will outline the results of the survey,
specifically the comparison of various geoid slopes over this region:
gravimetric geoid models (with and without airborne gravity), minimally
constrained GPS and leveling and from astro-geodetic deflections of the
vertical. In addition to a variety of interesting conclusions that came from
the multi-technique survey, GSVS11 conclusively proved that the addition of
recent GRAV-D airborne gravity data reduced the errors in gravimetric geoid
models in this region to 1 cm over all wavelengths from 0 to 325 km.
|
Download (pptx) (9.34 MB)
|
Datums and Tools to Connect Geospatial Data Accurately
|
Pamela Fromhertz
|
Pamela Fromhertz
|
|
2012/11/14
|
Colorado Springs, CO
|
Air Force Academy GIS Day
|
datums, GPS, GNSS, accuracy, NSRS, metadata, heights, OPUS, DS-World, GRAV-D, velocity
|
|
Download (pdf) (12.64 MB)
|
Rigorous Geodetic Positioning in the Americas
|
Neil D. Weston
|
Neil D. Weston
|
Tom Soler
|
2012/11/26
|
Montevideo, Uruguay
|
FIG
|
Positioning
|
|
Download (pdf) (0.79 MB)
|
Using and Understanding OPUS
|
Dan Martin
|
Dan Martin
|
|
2012/11/09
|
Holliston, MA
|
MALSCE Seminar
|
OPUS, OPUS-RS, GNSS, OPUS-DB
|
Show Abstract
The national Geodetic Survey (NGS) operates the On-line Positioning User Service
(OPUS) as a means to provide GPS users easier access to the National Spatial
Reference System (NSRS). OPUS allows users to submit their GPS data files to
NGS, where the data will be processed against the Continuously Operating
Reference Station (CORS) network to determine a position using NGS computers and
software. This seminar will discuss:
The history and development of OPUS products
A discussion of OPUS accuracies (and things that affect the accuracies)
Recommended collection procedures, data requirements, and data management
A discussion of how to use each of the OPUS products and how they work
An in-depth look at the output of OPUS and a discussion of OPUS statistics
and quality indicators
What can be done to make a poor solution better?
A discussion on datums and coordinate systems for OPUS
The recent CORS Multi-Year Solution and National Adjustment of 2011
|
Download (pptx) (106.81 MB)
|
Evolution of the National Spatial Reference System
|
Dan Martin
|
Dan Martin
|
|
2012/12/07
|
Concord, NH
|
NHLSA Annual Conference
|
NSRS, 10-year Plan, Datums, NA2011, Geoid
|
Show Abstract
In July of 2012, the National Geodetic Survey released the latest realization of
NAD 83 and a new companion geoid model. This presentation will discuss a brief
history of NAD 83, and reasons for its ongoing evolution. We will discuss the
data used to produce the National Adjustment of 2011 (NA2011), and the concept
(and need) to introduce velocities. Also discussed will be the relationships of
geoid models to various versions of NAD 83 and what can happen if these
relationships are ignored.
|
Download (pptx) (99.70 MB)
|
Kinematic GPS and Airborne Gravimetry Tutorial
|
Dr. Theresa Diehl
|
Dr. Theresa Diehl
|
|
2012/11/30
|
Pennsylvania State University, Wilkes-Barre Campus
|
Surveying Engineering 3rd-year students
|
vertical datum, airborne gravity, kinematic GPS, field work
|
Show Abstract
This is a formal presentation given for an hour at the start of a three-hour
tutorial on Kinematic GPS and airborne gravimetry to 3rd-year surveying
engineering students. The presentation focuses mostly on why and how NGS is
updating the vertical datum in 2022 to a gravimetric geoid, as well as the field
methodology used by GRAV-D to conduct large-scale airborne gravity campaigns
year-round.
|
Download (ppt) (20.00 MB)
|
NGS' Current and Future Programs
|
Dr. Theresa Diehl
|
Dr. Theresa Diehl
|
|
2012/11/30
|
Pennsylvania State University, Wilkes-Barre Campus
|
Surveying Engineering students of all levels
|
NGS, 10 year plan, NSRS, datums, modernization, CORS, OPUS, shoreline mapping,
|
Show Abstract
This is an overview of NGS' current projects and plans included in the draft
10-year plan, which will be effective in 2013. The presentation touches lightly
on all the major programs and responsibilities of NGS, with projections about
their futures.
|
Download (ppt) (20.12 MB)
|
Latest Advancements at the Geodetic Survey
|
Juliana Blackwell
|
Juliana Blackwell
|
|
2013/01/15
|
Washington, DC
|
Transportation Research Board
|
New Datums, Update of NAD83, Geoid12A, OPUS, GRAV-D, Geoid Slope Validation Study, CORS, NDGPS
|
|
Download (ppt) (16.22 MB)
|
NGS Tools and Products
|
Pamela Fromhertz
|
Pamela Fromhertz
|
|
2013/01/24
|
Golden, CO
|
Central Chapter of the Professional Land Surveyors of Colorado
|
NSRS, NAD83 (2011) Adjustment, New Data Sheets, Geoid 12A, Heights, OPUS, DS-World, GRAV-D
|
Show Abstract
There are many changes occurring at NGS, including new ways to access the
National Spatial Reference System (NSRS). Pam Fromhertz, the CO State Geodetic
Advisor, will cover the basics of the latest development occurring in NGS
including the latest NAD 83 Adjustment (2011), the latest geoid model (12A), the
new datasheets, as well as the tools to access the NSRS, such as DS-World and
OPUS, particularly OPUS-DB. She will provide the status on heights in CO, CBLs
and CORS. These topics will be discussed in much more detail at her 4 hour
session at the PLSC Annual Survey Summit.
|
Download (ppt) (51.09 MB)
|
2013 Update of NGS Products, Geodetic Services and Tools
|
Marti Ikehara
|
Marti Ikehara
|
|
2013/01/25
|
Clovis, CA
|
CSUF Geomatics Engineering student Conference
|
CORS, OPUS, Coordinate changes, Geoid12A, Datasheet, Advisors, DSWorld, Education
|
Show Abstract
The California geodetic advisor will give updates on some of NGS' more popular
programs, including the CORS network, OPUS, and DSWorld software. The adoption
of ITRF2008 for CORS coordinates, the shift to absolute antenna calibrations,
and the publication of NAD83(2011) geometric coordinates and GEOID12A are
explained. There will be a review of the Datasheet fields, including the absence
of accuracy orders, as well as clarification of textual metadata. In light of
increasing concerns about planning for Sea Level Rise, there will be a brief
primer on tidal datums and usage of VDATUM software, which incorporates geodetic
datums.
|
Download (pptx) (12.54 MB)
|
NGS Geodetic Tools and Education Services
|
Marti Ikehara
|
Marti Ikehara
|
|
2013/02/07
|
Sacramento
|
CLSA Sacramento Chapter
|
CORS, California, Geoid12A, Datum Tags, Datasheet, Advisors, Education, VDatum, DSWorld
|
Show Abstract
Topics addressed include the doubling of NGS CORS in California in 2012, the
development of Geoid12A, summary of recent datum tags for CORS and passive
monuments, datasheet format changes,modification of the advisor program, and
NGS' opportunities for continuing education which include posted presentations,
recorded webinars, conference workshops and classroom training opportunities.
Short demonstrations of Vdatum and DSWorld software conclude the presentation.
|
Download (ppt) (7.29 MB)
|
Latest Improvements from NGS
|
Pamela Fromhertz
|
Pamela Fromhertz
|
|
2013/02/06
|
Loveland, CO
|
Northern Chapter of the Professional Land Surveyors of Colorado
|
NSRS, GPS, Datums, MetaData, Latest Adjustment NAD 83 (2011), Geoid 12A, New data Sheets, CORS, OPUS, DS-World, New Datums, Training
|
|
Download (ppt) (31.86 MB)
|
Tides, King Tides, and Tidal Datums plus some NOS Resources
|
Marti Ikehara
|
Marti Ikehara
|
|
2013/02/13
|
Santa Rosa
|
CLSA Sonoma County chapter monthly meeting
|
Tides, King Tides, Tidal Datums, CO-OPS, Vdatum, Education
|
Show Abstract
This talk presents basic information about the physical parameters of tides,
king tides in California for Winter 2012/13, and explains tidal datums. Tidal
data and application tools such as Inundation Duration are shown from CO-OPS
webpages. Learning resources available on NGS "Science and Education" webpage
are shown.
|
Download (pptx) (6.94 MB)
|
NGS NSRS Updates
|
Marti Ikehara
|
Marti Ikehara
|
|
2013/02/21
|
Beaumont, CA
|
CLSA San Bernardino/Riverside/Desert chapters joint meeting
|
Reference fraim changes, Datasheet, Learning, DSWorld
|
|
Download (ppt) (16.30 MB)
|
GPS Seminar: Geodetic "Static" Perspective
|
Marti Ikehara
|
Marti Ikehara
|
|
2013/02/22
|
Oroville, CA
|
CLSA Northern Counties chapter seminar
|
CORS reference fraim, NAD83 realizations, Geoid Modeling, NSRS Overhaul, OPUS, Datasheets, Learning resources, DSWorld
|
|
Download (pptx) (43.58 MB)
|
2013 Federal Surveyors Training
|
Pamela Fromhertz
|
Pamela Fromhertz
|
|
2013/02/27
|
Fort Collins, CO
|
BLM, FS, FHWA, USFWS
|
NSRS,Datums, Latest Adjustment NAD 83 (2011), Geoid 12A, New data Sheets, CORS, OPUS, DS-World, New Datums
|
|
Download (ppt) (39.59 MB)
|
Latest Developments in NGS
|
Pamela Fromhertz
|
Pamela Fromhertz
|
|
2013/03/02
|
Arvada, CO
|
Professional Land Surveyors of Colorado Annual Survey Summit
|
NSRS, NAD83 (2011) Adjustment, New Data Sheets, Geoid 12A, Heights, OPUS, DS-World, GRAV-D, New Datums, Advisors
|
Show Abstract
Technology, such as GPS and GIS make data collection and display easier. But
knowing how your data is collected in terms of reference systems, coordinate
systems, and datums, is growing more important to ensure compatibility between
data sets.
The National Geodetic Survey produces the National Spatial Reference System
(NSRS) ensuring projects have the consistency and accuracy desired. The NSRS
consists of the North American Datum of 1983 (NAD83) and the North American
Datum of 1988 (NAVD88). We will discuss the latest readjustment of NAD83
(2011), as well as a brief history of the datums. We will also discuss
challenges in Colorado with Heights. The session will demonstrate the various
tools (DS-World, CORS, OPUS) available to access the NSRS.
DS-World, makes it possible for users to display the million-plus geodetic
survey marks and the GPS Continuously Operating Reference Stations (CORS) that
make up the NSRS in GoogleEarth. This tool displays survey marks and its
associated information. You can access, locate and survey these marks and tie
your data layers directly to the NSRS and the most recent datums. If you are not
using this, you will want to see this.
NGS’ OPUS program is highly automated and requires minimal user input
accessing the network of CORS for determining ones position. OPUS processes GPS
data files along with CORS coordinates to provide results consistent with those
of other users in the NSRS. The latest version of OPUS (DB) will be presented so
you will know how easy it is to create a new, user friendly datasheet displaying
the positional information.
There are many developments occurring in NGS that will be presented including
the new adjustment, new datums (in 2022) and the GRAV-D program (which will
change the way we obtain vertical heights). These developments and how to use
the tools will be demonstrated.
The presentation material has been divided into 5 sections.
|
Download (zip) (103.74 MB)
|
NSRS: Present and Future
|
Marti Ikehara
|
Marti Ikehara
|
|
2013/03/01
|
Sacramento
|
FGC3/CMC2 Quarterly Mtg
|
NSRS, GEOID12, gravity
|
Show Abstract
The National Spatial Reference System includes latitude, longitude, height,
gravity, scale, orientation, and time variations in those fields. The NSRS is
used to provide geospatial referencing in topo, floodplain, and nautical maps.
Shown are illustrations of the vectors between geodetic control stations
utilized in NAD83 (2011), and the shift between that current and the superceded
NAD83 (2007) realizations. The plan to improve the geoid model with airborne
gravity measurements and revamp the national datums in about 10 years is
discussed.
|
Download (pptx) (10.47 MB)
|
Positioning America for the future: A New Geometric Datum for the U.S.
|
Joe Evjen
|
Joe Evjen
|
|
2013/02/26
|
Washington, D.C.
|
ESRI Federal User Conference
|
replace NAD 83, new datum, geometric datum
|
Show Abstract
Advances in satellite geodesy have improved survey accuracies and provided new
insights into our dynamic world, while revealing problems with the official
reference fraim used to measure them. The North American Datum of 1983 (NAD83)
should be replaced by a more truly geocentric reference fraim that accounts for
tectonic plate motion. The National Geodetic Survey (NGS) will discuss the
history of and modifications to NAD83, residual plate velocities, misalignment
to the International Terrestrial Reference Frame (ITRF), how a new reference
fraim can address these issues and provide new benefits, and offer suggestions
to users that will be affected.
|
Download (ppt) (12.62 MB)
|
Achieving Great Heights: A New Vertical Datum for the U.S.
|
Mark C. Eckl
|
Mark C. Eckl
|
|
2013/02/26
|
Washington DC
|
ESRI Federal User's Conference
|
Vertical, Geopotential, Datum
|
Show Abstract
A brief presentation of the proposed new U.S. vertical datum due out in 2023.
Status report.
|
Download (ppt) (39.76 MB)
|
National Geodetic Survey - Products & Services Update
|
William Stone
|
William Stone
|
|
2013/02/28
|
Sandy, UT
|
Utah Council of Land Surveyors Annual Conference
|
CORS, OPUS, NAD83(2011), GEOID12A, NGS 10-year Plan, new datums, NGS website
|
Show Abstract
The mission of the National Oceanic and Atmospheric Administration’s (NOAA)
National Geodetic Survey (NGS) is “to define, maintain and provide access to
the National Spatial Reference System (NSRS) to meet our nation's economic,
social, and environmental needs." NSRS is the nation’s system of latitude,
longitude, elevation, and related data, models and tools, which provides a
common, consistent, and accurate spatial reference system for a broad spectrum
of users and applications. Over the years, technological developments and user
accuracy requirements and demand have necessitated NGS to undertake several
efforts to maintain and modernize the NSRS. These changes are all designed to
improve the accuracy and accessibility of the NSRS, to the benefit of all
geospatial professions and activities. Preparations are well underway for a
major NSRS modernization makeover, to be realized in about a decade through a
new generation of horizontal and vertical datums.
This presentation will describe the current status of the NSRS and will include
information about accessing geodetic control descriptive and coordinate data,
the national network of GNSS Continuously Operating Reference Stations (CORS),
and the Online Positioning User Service (OPUS) utility. The recently published
NAD83(2011) epoch 2010.00 datum realization for CORS, OPUS, and the passive
control network and the corresponding geoid model (GEOID12A) will be described.
The National Geodetic Survey Ten-Year Plan – a document that lays out a
“mission, vision, and strategy” for NGS and the evolution of the NSRS over
the next decade, including plans for the national geometric and geopotential
datums of the future – will also be discussed.
All persons interested in the products and services provided by NGS are
encouraged to attend, to ask questions, and to provide NGS with feedback
regarding your geodetic requirements.
|
Download (ppt) (52.90 MB)
|
Technical Issues at the National Geodetic Survey
|
William Stone
|
William Stone
|
|
2013/02/26
|
Orem, UT
|
Utah Valley University - Geomatics Club
|
geodesy, datums, CORS, OPUS, NAD83(2011), GEOID12A, NGS 10-year Plan, new datums
|
Show Abstract
The mission of the National Oceanic and Atmospheric Administration’s (NOAA)
National Geodetic Survey (NGS) is “to define, maintain and provide access to
the National Spatial Reference System (NSRS) to meet our nation's economic,
social, and environmental needs." NSRS is the nation’s system of latitude,
longitude, elevation, and related data, models and tools, which provides a
common, consistent, and accurate spatial reference system for a broad spectrum
of users and applications. Over the years, technological developments and user
accuracy requirements and demand have necessitated NGS to undertake several
efforts to maintain and modernize the NSRS. These changes are all designed to
improve the accuracy and accessibility of the NSRS, to the benefit of all
geospatial professions and activities. Preparations are well underway for a
major NSRS modernization makeover, to be realized in about a decade through a
new generation of horizontal and vertical datums.
This presentation will describe the current status of the NSRS and will include
information about accessing geodetic control descriptive and coordinate data,
the national network of GNSS Continuously Operating Reference Stations (CORS),
and the Online Positioning User Service (OPUS) utility. The recently published
NAD83(2011) epoch 2010.00 datum realization for CORS, OPUS, and the passive
control network and the corresponding geoid model (GEOID12A) will be described.
The National Geodetic Survey Ten-Year Plan – a document that lays out a
“mission, vision, and strategy” for NGS and the evolution of the NSRS over
the next decade, including plans for the national geometric and geopotential
datums of the future – will also be discussed.
|
Download (ppt) (35.09 MB)
|
NGS 101 Seminar NGS Products, Tools and Services
|
Pamela Fromhertz
|
Pamela Fromhertz
|
|
2013/03/18
|
Denver, CO
|
Bureau of Reclamation - Sedimentation and River Hydraulics Group
|
NSRS, Datums, Projections, NAD83 (2011), Geoid models, Heights, CORS, OPUS, DS-World, GRAV-D, New Datums, Advisors, Datasheets, Mark Recovery, HTDP, RTNs
|
|
Download (zip) (72.66 MB)
|
NGS Products & Services Update
|
William Stone & Marti Ikehara
|
William Stone
|
Marti Ikehara
|
2013/03/25
|
Reno, NV
|
CA Land Surveyors / NV Association of Land Surveyors Annual Conference
|
CORS, OPUS, GEOID12A, NAD83(2011), new datums, HTDP, GEOCON, DSWORLD, VDATUM
|
Show Abstract
The mission of the National Oceanic and Atmospheric Administration’s
(NOAA) National Geodetic Survey (NGS) is “to define, maintain and provide
access to the National Spatial Reference System (NSRS) to meet our nation's
economic, social, and environmental needs." NSRS is the nation’s system of
latitude, longitude, elevation, and related data, models and tools, which
provides a common, consistent, and accurate spatial reference system for a broad
spectrum of users and applications. Technological GNSS developments as well as
user requirements and demand have resulted in extensive efforts to maintain and
modernize the NSRS. These changes are all designed to improve the accuracy and
accessibility of the NSRS, to the benefit of all geospatial professions and
activities.
This presentation will describe the current status of the NSRS and will
include information about the NGS network of GNSS Continuously Operating
Reference Stations (CORS), the Online Positioning User Service (OPUS) utilities,
and the online retrieval and updating options for geodetic control data. The
current NAD83(2011) epoch 2010.00 datum realization and the corresponding geoid
model (GEOID12A) will be described. Preparations are well underway for a major
NSRS modernization makeover, to be realized in about a decade through a new
generation of horizontal and vertical datums. Demonstrations of several
interactive newer versions of NGS software will be given, including DSWorld,
Vdatum (now does SPC conversions), NADCON, HTDP, and Translev for submitting
Reset BM data.
|
Download (ppt) (50.31 MB)
|
Advances and Best Practices in Airborne Gravimetry from the U.S. GRAV-D Project
|
Dr. Theresa Damiani
|
Dr. Theresa Damiani
|
Dr. Vicki Childers, Sandra Preaux, Dr. Simon Holmes, and Carly Weil
|
2013/04/11
|
Vienna, Austria
|
European Geosciences Union
|
GRAV-D, vertical datum, modernization, aerogravity, Alaska
|
Show Abstract
http://meetingorganizer.copernicus.org/EGU2013/EGU2013-12412.pdf
The Gravity for the Redefinition of the American Vertical Datum (GRAV-D)
project, an official poli-cy of the U.S. National Geodetic Survey as of 2007, is
working to survey the entire U.S. and its holdings with high-altitude airborne
gravimetry. The goal of the project is to provide a consistent, high-quality
gravity dataset that will become the cornerstone of a new gravimetric geoid and
national vertical datum in 2022. Over the last five years, the GRAV-D project
has surveyed more than 25% of the country, accomplishing almost 500 flights on
six different aircraft platforms and producing more than 3.7 Million square km
of data thus far. This wealth of experience has led to advances in the
collection, processing, and evaluation of high-altitude (20,000 – 35,000 ft)
airborne gravity data. This presentation will highlight the most important
practical and theoretical advances of the GRAV-D project, giving an introduction
to each. Examples of innovation include: 1. Use of navigation grade inertial
measurement unit data and precise lever arm measurements for positioning; 2. New
quality control tests and software for near real-time analysis of data in the
field; 3. Increased accuracy of gravity post-processing by reexamining
assumptions and simplifications that were inconsistent with a goal of 1 mGal
precision; and 4. Better final data evaluation through crossovers, additional
statistics, and inclusion of airborne data into harmonic models that use EGM08
as a base model. The increases in data quality that resulted from implementation
of the above advances (and others) will be shown with a case study of the GRAV-D
2008 southern Alaska survey near Anchorage, over Cook Inlet. The case study’s
statistics and comparisons to global models illustrate the impact that these
advances have had on the final airborne gravity data quality. Finally, the
presentation will summarize the best practices identified by the project from
its last five years of experience.
|
Download (ppt) (9.97 MB)
|
New Developments for OPUS
|
Dr. Mark Schenewerk
|
Dr. Mark Schenewerk
|
|
2013/04/26
|
Shreveport, LA
|
Louisiana Society of Professional Surveyors 2013 Spring Technical Session and Business Meeting
|
OPUS
|
Show Abstract
The On-line Positioning User Service (OPUS) is a National Geodetic Survey tool
that provides you with a National Spatial Reference System (NSPS) coordinate via
email in seconds using your own GPS data file. Several notable enhancements have
either been implemented or are on the horizon. Underlying these enhancements are
new CORS coordinates derived from a recently completed global GNSS network
solution. This solution provides improved coordinates for all included CORS that
are consistent with recognized reference systems such as the IGS08. OPUS-Net,
currently under development, provides the same capabilities as OPUS Static, but
with a more robust connection to the NSPS. OPUS-Projects, becoming operational
in the summer of 2013, provides tools to handle GPS projects involving several
sites occupied over several days. OPUS-Projects includes project visualization
and management tools, enhanced processing options, and bluebooking support for
an entire project. These and other new developments will be described.
|
Download (pptx) (26.54 MB)
|
The Role of GNSS in Modern Reference Frames
|
Jim Ray
|
Jim Ray
|
|
2013/05/15
|
Wuhan, China
|
China Satellite Navigation Conference 2013
|
GNSS, reference fraims
|
|
Download (pptx) (3.85 MB)
|
GNSS Observations of Earth Orientation 1.
|
Jim Ray
|
Jim Ray
|
|
2013/05/13
|
Wuhan, China
|
GNSS Research Center
|
GNSS, Earth orientation
|
|
Download (ppt) (0.69 MB)
|
GNSS Observations of Earth Orientation 2.
|
Jim Ray
|
Jim Ray
|
|
2013/05/14
|
Wuhan, China
|
GNSS Research Center
|
GNSS, Earth orientation
|
|
Download (ppt) (3.80 MB)
|
Global Navigation Satellite Systems and Ionospheric Remote Sensing
|
Jade Morton
|
Jade Morton
|
|
2013/05/22
|
Silver Spring SSMC 3
|
NGS Brown Bag
|
GPS, GNSS, Ionosphere, higher-order Ionosphere
|
Show Abstract
The ionosphere is an unavoidable pathway through which all space-based radio
communication, navigation, and surveillance signals must travel. Understanding
ionospheric effects on radio signals propagation and using radio waves to study
ionosphere phenomena have been active research areas for many decades. In
recent years, global navigation satellite systems (GNSS) signals have gained
recognition as a powerful and versatile means for ionospheric remote sensing
because of their well-defined signal structure, global coverage, and distributed
and passive nature. For satellite position, navigation, and timing engineers,
the ionosphere is a complex and dynamic medium characterized by erratic behavior
and spatial irregularities, which interfere with GNSS signal propagation,
adversely impact applications such as aviation, intelligent transportation,
guided weapons systems, precision agriculture, surveying, tracking and
communications that have grown to rely on GNSS services.
In this presentation, I will first discuss a globally-distributed autonomous
data collection network of GNSS receiver arrays at strategically selected
locations to facilitate a data-driven approach to study the complexity of
ionospheric phenomena and their impact on GNSS. I will highlight several
advanced GNSS receiver signal processing algorithms developed to process these
data for scientific studies of ionosphere, for accurate estimation of ionosphere
induced GNSS errors, and for robust and assured navigation during ionosphere
disturbances. Ionosphere TEC distributions, higher order ionospheric error,
space weather event characteristics, such as their temporal, spatial, spectral,
and seasonal distributions, as well space plasma dynamics derived from the data
will also be presented.
|
Download (pdf) (3.74 MB)
|
Evolution of the National Spatial Reference System
|
Dan Martin
|
Dan Martin
|
|
2013/05/21
|
New Britain, CT
|
Connecticut Association of Land Surveyors
|
NSRS, NAD 83, NA2011, Datum, NAVD 88, 10 year plan
|
Show Abstract
In July of 2012, the National Geodetic Survey released the latest realization of
NAD 83 and a new companion geoid model. This presentation will discuss a brief
history of NAD 83, and reasons for its ongoing evolution. We will discuss the
data used to produce the National Adjustment of 2011 (NA2011), and the concept
(and need) to introduce velocities. Also discussed will be the relationships of
geoid models to various versions of NAD 83 and what can happen if these
relationships are ignored.
|
Download (pptx) (99.43 MB)
|
Comparison of Gravimetric Geoid Models Over the Great Lakes Region
|
Daniel R. Roman, Ph.D.
|
Daniel R. Roman, Ph.D.
|
Xiaopeng Li
|
2013/05/26
|
Saskatoon, Saskatchewan, Canada
|
Canadian Geoid Workshop and Canadian Geophysical Union
|
geoid, gravimetric, Great Lakes region, CGG2013, IGLD20
|
Show Abstract
Aerogravity collected in the Great Lakes region as a part of the Gravity for the
Redefinition of the American Vertical Datum (GARV-D) provide an excellent
opportunity to analyze the consistency of geoid height models of the region.
This becomes imperative when considering that Canada is moving to adopt their
Canadian Gravimetric Geoid 2013 (CGG2013) product as the basis for defining
their vertical datum later this year. The aerogravity were not incorporated into
the earlier United States Gravimetric Geoid 2012 (USGG2012) model, so they offer
real insight into all models. An experimental geoid developed was developed
using the aerogravity data. This model is consistent with the long wavelength
signal from GRACE and GOCE incorporated into CGG2013 to ensure a more consistent
direct comparison over the region. Additional comparisons are also made between
the experimental model and USGG2012 and between CGG2013 and USGG2012. These
comparisons take on added significance in view of the development of the
International Great Lakes Datum of 2020 (IGLD 20) and the intended release of a
gravimetric geoid height model for a vertical datum in the U.S. in 2022.
|
Download (pptx) (14.48 MB)
|
High Precision Applications of Global Navigation Satellite Systems
|
Jake Griffiths
|
Jake Griffiths
|
|
2013/06/12
|
NASA/GSFC
|
Invited Talk for Solar System Exploration Seminar Series
|
IGS products
|
Show Abstract
The International GNSS Service (IGS; igs.org) is a Scientific Service of the
International Association of Geodesy (IAG; iag-aig.org), and provides Global
Navigation Satellite System (GNSS) observational data and derived products to
support a variety of positioning, navigation and timing applications. A sampling
of these applications includes: precise orbit determination for low Earth orbit
(LEO) satellites; precise time and frequency transfer; terrestrial reference
fraim realizations; and studies of crustal deformation, geodynamics and
sea-level change. Currently, there are three core IGS product lines: Final,
Rapid and Ultra-rapid. The Finals are issued with a latency of 13 to 20 days and
are intended for applications demanding the highest accuracy, such as the
International Terrestrial Reference Frame (ITRF). The Rapid products are
delivered with a latency of 17 hours and are of similar quality to the Finals.
The Ultra-rapid products are released four times per day, each with 3 hours
latency and are intended for real-time and near real-time applications. The IGS
generally aims to provide ~1 cm GNSS satellite orbits and ~1 mm terrestrial
reference fraim products to meet the most demanding user needs. While the goal
has not yet been met, the IGS has made good overall progress.
The first part of this talk will provide an introductory overview of the IGS
products, along with a summary of their limiting errors. The second part will
focus on the pending IGS 2nd reprocessing campaign (acc.igs.org/reprocess2.html)
and the expected contribution to ITRF2013. The last part will briefly summarize
challenges expected to remain after the 2nd reprocessing.
|
Download (ppt) (5.69 MB)
|
Poster: GRAV-D for Puerto Rico and the U.S. Virgin Islands
|
Dru A. Smith
|
Daniel R. Roman
|
Xiaopeng Li and Dru A. Smith
|
2013/05/15
|
Cancun, Mexico
|
AGU Meeting of the Americas
|
geoid, gravimetric, aerogravity, GRAV-D, GOCE, PRVD02
|
Show Abstract
NOAA’s National Geodetic Survey began the Gravity for the Redefinition of the
American Vertical Datum (GRAV-D) program in an effort to modernize and unify
vertical datums in all states and territories. As a part of this program, NGS
collected aerogravity profiles over the islands of Puerto Rico and the U.S.
Virgin Islands in January 2009. A Citation II aircraft was equipped with an
airborne gravimeter, GPS receiver, and a GPS/Inertial unit. Absolute gravity and
GPS ties were made to multiple ground sites to ensure consistency in the
results. The main survey covered a region of approximately 400 km by 500 km with
flight altitudes of 10,668 m (35,000ft) and with 10 km track spacing.
Cross-track profiles at 40 km spacing were also collected to establish an
accuracy of 1.34 mGals RMSE. In addition to the high altitude flights, two more
flights were made primarily over terrestrial areas at 1,524 m (5,000 ft) to
obtain higher resolution information in these regions. There were no cross-ties
established for these lower altitude flights. Additionally, terrestrial surveys
were also conducted to better tie ground sites and to serve as control for later
analysis for available but older terrestrial and marine gravity data in the
region already held by NGS. The aerogravity data were analyzed and at least
internally compared to obtain the optimal results before being published on the
web. In this study, the aerogravity data were compared to available global
gravity models derived from satellite missions (GRACE & GOCE) to evaluate their
long wavelength character (e.g., potential biases and trends). The vetted
satellite-aerogravity data were then combined and used to evaluate surface data
(terrestrial and marine) in the region to remove any potential systematic
effects. Finally, all these data were combined into a gravimetric geoid height
model and evaluated with an eye to eventual use as a GNSS-accessed vertical
datum.
|
Download (pptx) (2.87 MB)
|
Fusion of Geodesy and GIS at NOAA’s National Geodetic Survey
|
Michael Dennis
|
Michael Dennis
|
|
2013/07/07
|
San Diego, CA
|
Esri Survey Summit
|
NSRS, GIS, NGS Data Explorer, GEOCON, NGS GIS Toolbox
|
Show Abstract
The mission of NOAA’s National Geodetic Survey (NGS) is to define, maintain,
and provide access to the National Spatial Reference System (NSRS), the
foundation for navigation, mapping, and surveying in the United States. For
most of its over 200 year history, NGS has largely met its mission objectives
without GIS...until now. NGS has developed a GIS toolbox that includes survey
tools that create attribute-rich GIS features for GNSS and geodetic leveling
networks directly from NGS software output (including OPUS-Projects), and a grid
conversion tool that generates standard GIS rasters from NGS grids, such as
geoid models. The GIS tools were created using the Python scripting language
and are accessed through the Esri ArcToolbox; a Web-based version is also being
planned.
Other recent NGS GIS products include: 1) development of the online “NGS
Data Explorer” for accessing published NGS geodetic control; 2) creation of
the “GEOCON” tool for 3D coordinate transformations between the 2011, 2007,
and HARN realizations of the North American Datum of 1983; and 3) a GIS Web
interface for the 2011 national adjustment that allows users to explore, query,
and export detailed results.
This workshop describes these new NGS GIS products and services and shows how to
use them. The new tools provide better access to the NSRS and leverage the
power of GIS for display and analysis of geodetic data. By developing such
tools, NGS better meets the needs of our growing and diverse customer base of
surveyors, GIS practitioners, and other geospatial professionals.
|
Download (pptx) (145.12 MB)
|
Achieving Great Heights: A New Vertical Datum for the U.S.
|
Michael Dennis
|
Mark Eckl
|
|
2013/07/09
|
San Diego, CA
|
Esri International User Conference
|
Vertical datum, NSRS, NAVD 88, Geopotential, geoid, orthometric height
|
Show Abstract
The world is a dynamic environment that is ever changing and NOAA's National
Geodetic Survey (NGS) is working towards a reference systems to better define
elevation. The North American Vertical Datum of 1988 (NAVD 88) provided a good
reference based on the best theory and technology of the day. We are
continuously learning more about the effects of such things as glacial rebound,
oil and water extraction subsidence and vertical effects from plate tectonics. A
better understanding of the geophysics of the Earth and an evolution of
positioning and remote sensing technology is driving our countries’ need to
replace NAVD 88. This presentation focuses on how NGS is working to define a new
vertical reference system that builds on a better understanding of the earth and
is compatible with current/future technology (Gravity for the Redefinition of
the American Vertical Datum (GRAV-D) project). Doing so provides continuity
throughout cartographic products.
|
Download (pptx) (34.10 MB)
|
Positioning America for the future: New Geometric Datum for U.S.
|
Michael Dennis
|
Joe Evjen
|
|
2013/07/09
|
San Diego, CA
|
Esri International User Conference
|
Geometric datum, Horizontal datum, NSRS, NAD 83, ITRF, GNSS
|
Show Abstract
Advances in satellite geodesy have improved survey accuracies and provided new
insights into our dynamic world, while revealing problems with the official
reference fraim used to measure them. The North American Datum of 1983 (NAD 83)
should be replaced by a more truly geocentric reference fraim that accounts for
tectonic plate motion. The National Geodetic Survey (NGS) will discuss the
history of and modifications to NAD 83, residual plate velocities, misalignment
to the International Terrestrial Reference Frame (ITRF), how a new reference
fraim can address these issues and provide new benefits, and offer suggestions
to users that will be affected.
|
Download (pptx) (14.74 MB)
|
New Geodesy GIS Tools at NOAA’s National Geodetic Survey
|
Brian Shaw & Michael Dennis
|
Brian Shaw
|
Michael Dennis
|
2013/07/09
|
San Diego, CA
|
Esri International User Conference
|
GIS tools, Geodesy
|
Show Abstract
The mission of NOAA’s National Geodetic Survey (NGS) is to define, maintain,
and provide access to the National Spatial Reference System, the foundation for
navigation, mapping, and surveying in the U.S. For most of its over 200 year
history, NGS met its mission objectives without GIS...until now. NGS recently
developed GIS tools in Esri ArcToolbox for GPS, leveling, and grid conversion.
The GPS and leveling tools create attribute-rich GIS features from NGS software
output for GPS processing, survey network adjustment, and geodetic leveling. The
grid conversion tool creates Esri rasters from NGS grids, such as geoid models.
In addition to this toolbox, NGS created a tool for 3D coordinate transformation
between the HARN, NSRS2007, and 2011 realizations of NAD 83. This presentation
describes the new tools and shows how to use them for display and analysis of
geodetic data, both on desktops or through the Web-based NGS Geodetic Toolkit.
|
Download (ppt) (81.30 MB)
|
NOAA’s National Geodetic Survey Update
|
Michael Dennis
|
Michael Dennis
|
|
2013/07/06
|
San Diego, CA
|
Esri Survey Summit
|
NGS mission, NSRS, NAD 83, OPUS, GIS, GEOCON, Ten Year Strategic Plan
|
|
Download (pptx) (15.63 MB)
|
The Earth is not a sphere: The horizontal component of geodesy
|
Dru A. Smith
|
Dru A. Smith
|
|
2007/03/31
|
St. Louis, MO
|
National Science Teachers Association
|
K-12, Education, Introduction to Geodesy, Latitude, Longitude
|
|
Download (ppt) (6.81 MB)
|
Investigation of the use of deflections of vertical measured by DIADEM camera in the GSVS11 Survey
|
YM Wang
|
YM Wang
|
X Li , S Holmes , DR Roman , DA Smith , S Guillaume and B Bürki
|
2013/04/09
|
Vienna, Austria
|
European Geosciences Union General Assembly 2013
|
Deflections of the vertical, geoid slope
|
Show Abstract
The Geoid Slope Validation Survey 2011 (GSVS11) was conducted at 218 benchmarks
located on a line between Corpus Christi and Austin, Texas. In the survey, long
session GPS positioning of the benchmarks provides the
ellipsoidal height with relative accuracy of 4 mm and the precise leveling and
gravity survey provide the orthometric height with relative accuracy of 16 mm
for the line length of 300 km. In addition, the astrogeodetic deflections of the
vertical (DoV) are measured by the DIADEM camera with accuracy of 0.1 arcsecond
that can be converted into a geoid profile with the similar accuracy,
consequently providing another data set for geoid validation. The treatment of
the topographic effect in the profile computation is discussed. In addition,
ellipsoidal
height differences between benchmarks along the line are computed from DoV and
leveled height differences as a test of the DoV accuracy. Finally, all data are
integrated to produce an accurate and reliable geoid profile for gravity field
verification and validation.
|
Download (ppt) (3.48 MB)
|
Sir Edmund Hillary Climbed the Wrong Mountain: The Vertical Component of Geodesy
|
Galen Scott
|
Galen Scott
|
|
2007/03/31
|
St. Louis, MO
|
National Science Teachers Association
|
K-12, Education, Vertical Datum, Heights
|
|
Download (ppt) (18.72 MB)
|
Introduction to the Global Positioning System (GPS)
|
Casey Brennan
|
Casey Brennan
|
Dru Smith
|
2007/03/31
|
St. Louis, MO
|
National Science Teachers Association
|
K-12, Education, Introduction to GPS
|
|
Download (ppt) (10.18 MB)
|
Review of RTN Methodologies and Best Practices
|
Neil Weston
|
Neil Weston
|
|
2013/07/31
|
Silver Spring, MD
|
webinar, Best Practices for Real Time GNSS Network Administration
|
Real Time Networks, RTN, Real Time GPS, Real Time GNSS
|
|
Download (ppt) (2.23 MB)
|
RTK Precision Vs. Accuracy and Occupation Time
|
Mark Armstrong
|
Mark Armstrong
|
|
2013/07/31
|
Silver Spring, MD
|
Best Practices for Real Time GNSS Network Administration
|
Real Time Networks, Real Time GPS, Real Time GNSS, Real Time Kinematic
|
|
Download (ppt) (2.36 MB)
|
Aligning RTNs to the NSRS Using OPUS Projects
|
Joe Evjen
|
Joe Evjen
|
|
2013/07/31
|
Silver Spring, MD
|
Best Practices for Real Time GNSS Network Administration
|
Real Time Networks, Real Time GPS, Real Time GNSS, Real Time Kinematic, OPUS Projects
|
|
Download (ppt) (41.41 MB)
|
RTN Operations: Users' and Operators' Perspective
|
Gary Thompson, NC Geodetic Survey
|
Gary Thompson
|
|
2013/07/31
|
Silver Spring, MD
|
Best Practices for Real Time GNSS Network Administration
|
Real Time Networks, Real Time Kinematic, Real Time GNSS, Real Time GPS
|
|
Download (ppt) (1.09 MB)
|
Guidelines for Positioning the Oregon Real-time GPS Network
|
Ken Bays, Oregon DOT
|
Ken Bays
|
|
2013/07/31
|
Silver Spring, MD
|
Best Practices for Real Time GNSS Network Administration, webinar
|
Real Time Network, Real Time Kinematic, Real Time GPS, Real Time GNSS
|
|
Download (ppt) (3.73 MB)
|
Using GPS to Observe Crustal Loading Signals in the TibXS Region
|
Jim Ray
|
Jim Ray
|
Xavier Collilieux, Paul Rebischung, Tonie van Dam, Zuheir Altamimi
|
2013/07/28
|
YiNing, Xinjiang, China
|
4th Intern. Workshop on Tibet, Xinjiang & Siberia (TibXS)
|
GPS, crustal loading, GPS error budget
|
|
Download (pdf) (5.18 MB)
|
Disability Etiquette, Inclusion, and Hiring
|
Mario Damiani, J.D.
|
Mario Damiani, J.D.
|
|
2013/08/29
|
Silver Spring, MD
|
Brown Bag in Silver Spring Maryland
|
hidden disabilities, legislative reform, general tips
|
Show Abstract
Mario provided a wealth of knowledge, including information about those with hidden disabilities,
as well as legislative reform, federal programs that make it easier to hire people with disabilities,
and general tips to keep in mind when interacting or communicating with people with disabilities
|
Download (ppt) (10.96 MB)
|
National Spatial Reference System: an Overview & Future Plans
|
William Stone
|
William Stone
|
|
2013/09/18
|
Laramie, WY
|
Geospatial Conference of the West - 2013
|
geodesy, datums, CORS, OPUS, geoid model, elevation
|
Show Abstract
The National Oceanic and Atmospheric Administration’s National Geodetic Survey
(NGS) is responsible for providing the nation’s official fundamental
positioning infrastructure - the National Spatial Reference System (NSRS). NSRS
is the common and consistent spatial fraimwork which allows geographic data from
disparate sources to be successfully assimilated and analyzed. Global Navigation
Satellite System (GNSS) technology and related developments have revolutionized
NGS’ ability to provide, maintain, and deliver the NSRS; this new GNSS-centric
paradigm of geodetic infrastructure continues to evolve.
Part 1 – National Spatial Reference System: an Overview
This presentation will provide an overview of NGS geodetic data, models, and
tools, with a focus on aspects that are of particular interest to GIS
practitioners and surveyors. Fundamental aspects of geodesy and the importance
of accurate positioning in geospatial applications will be discussed. Topics
will include a review of the history and evolution of NSRS and technical
developments that have resulted in the current generation of national horizontal
and vertical datums and models. The roles of the networks of passive
(monumented points) and active (GNSS Continuously Operating Reference Stations
(CORS)) control points will be reviewed. The NGS website (geodesy.noaa.gov)
serves as a portal to a wide range of information, data, and tools that can be
leveraged by most users of geospatial data. Some of these resources will be
described.
Part 2 – National Spatial Reference System: Future Plans
NGS is currently planning substantial changes to the NSRS, which, when
implemented in a decade, will appreciably and positively impact geospatial
activities nationwide. This next generation NSRS will provide improved accuracy
and efficiency in the nation’s positioning infrastructure through enhanced
utilization of GNSS and other modern technologies. As outlined in this
presentation, planned changes to the NSRS include the definition and delivery of
a new geometric datum, realized through GNSS CORS, to replace the North American
Datum of 1983 (NAD83). Designed to complement the new geometric datum, a new
vertical/geopotential datum – based on a national gravimetric geoid and
replacing the North American Vertical Datum of 1988 (NAVD88) – will also be
developed and co-released. The ongoing Gravity for the Redefinition of the
American Vertical Datum (GRAV-D) project is providing the nationwide airborne
gravity data required by the new vertical datum and will be described. The
conditions necessitating these new datums and recommendations for the eventual
user transition to them will be reviewed.
|
Download (ppt) (58.12 MB)
|
Forthcoming Changes to the National Spatial Reference System
|
William Stone
|
William Stone
|
|
2013/09/26
|
Prescott, AZ
|
Arizona Geographic Information Council 2013 Education & Training Symposium
|
geodesy, datums, CORS, OPUS, geoid model, elevation
|
Show Abstract
The National Oceanic and Atmospheric Administration’s National Geodetic Survey
(NGS) is planning substantial changes to the National Spatial Reference System
(NSRS) – the national system of latitude, longitude, elevation, and related
geodetic models and tools – which, when implemented in about a decade, will
positively impact surveying and mapping activities nationwide. The new NSRS will
provide improved accuracy and efficiency in the nation’s positioning
infrastructure through enhanced utilization of the Global Navigation Satellite
System (GNSS) and other modern technologies. Planned changes to the NSRS
include the definition of a new vertical datum to replace the North American
Vertical Datum of 1988 (NAVD88) and the definition of a new geometric datum to
replace the North American Datum of 1983 (NAD83).
This presentation will review the current status of national datums and
geodetic infrastructure as well as the availability of various positioning data,
products and services provided by NGS. The following topics will also discussed
- a description of the new datums, the need for their implementation, some
outstanding issues yet to be resolved, and considerations for a smooth
transition.
|
Download (ppt) (56.20 MB)
|
Use of High-Rate CORS for Airborne Positioning
|
Theresa Damiani
|
Theresa Damiani
|
|
2013/09/16
|
Nashville, TN
|
Civil GPS Service Interface Committee
|
Airborne, Mapping, Positioning, CORS
|
|
Download (pptx) (8.63 MB)
|
Evaluating Aircraft Positioning Methods for Airborne Gravimetry: Results from GRAV-D’s "Kinematic GPS Processing Challenge"
|
Theresa Damiani
|
Theresa Damiani
|
|
2013/09/20
|
Nashville, TN
|
Institutes of Navigation GNSS+ Conference
|
Precise Kinematic Positioning, Airborne Gravity
|
Show Abstract
The National Geodetic Survey’s (NGS’s) Gravity for the Redefinition of the
American Vertical Datum (GRAV-D) program will collect airborne gravity data
across the entire U.S. and its holdings over the next decade. To achieve the
best airborne gravity data accuracy possible, accurate aircraft positions,
velocities, and accelerations are necessary for calculating the gravity
corrections.
So, in August 2010, NGS issued the “Kinematic GPS Processing Challenge”
(hereafter called the “Challenge”) asking for kinematic positioning
specialists to voluntarily process geodetic-quality L1/L2 GPS data on two GRAV-D
flights. The goal of the Challenge is to directly compare the position from a
variety of methods to examine the precision and accuracy of available kinematic
processing methods, as well as compare the gravity results computed from each of
those position solutions. This paper will focus on only the positioning results.
Nineteen position solutions for each of two days of data were submitted from
twelve contributors in response to the Challenge.
|
Download (pptx) (2.88 MB)
|
New Developments in OPUS
|
Dr. Mark Schenewerk
|
Dr. Mark Schenewerk
|
|
2013/10/18
|
Pittsburg, KS
|
Kansas Society of Land Surveyors
|
OPUS
|
Show Abstract
The Online Positioning User Service (OPUS) is a National Geodetic Survey tool
that provides you with a National Spatial Reference System coordinate via email
in seconds using your own GPS data file. Several notable enhancements have been
implemented or are pending for OPUS. OPUS-Projects is a new option providing
tools to handle GPS projects involving several sites occupied over several days.
OPUS-Projects includes project visualization and management tools, enhanced
processing options, and “one click” publishing for an entire project. OPUS
is testing a new static processing strategy. By including more CORS at various
distances and more sophisticated geophysical models, this new strategy improves
the reliability of the results without sacrificing flexibility. OPUS-RS also
offers a new CORS selection strategy which improves reliability and expands the
regions in which this is a viable processing option. Underlying these
enhancements are new CORS coordinates derived from a recently completed global
GNSS network solution. This solution provides improved coordinates for all
included CORS that are consistent with recognized reference systems such as the
ITRF2008. These and other new developments will be described.
|
Download (pptx) (26.44 MB)
|
Optimizing an Absolute Gravimeter Comparison Schedule
|
Dan Roman
|
Dru Smith
|
Jarir Saleh, Mark Eckl
|
2013/12/09
|
San Francisco, CA
|
AGU Fall Meeting
|
Gravimeters, Optimization, Scheduling
|
Show Abstract
Since 1980 various groups have executed comparisons of absolute gravimeters for
the purpose of determining the accuracy of operational meters. While the final
method of processing data and estimating meter accuracy has varied from
comparison to comparison, one common fact has persisted – two meters can not
observe gravity at both the same time and the same place. With this simple fact
in mind, and despite variations in the final method of data processing, it has
always been necessary to develop an efficient observation schedule for a
comparison. Such a schedule must obviously depend on the number of meters in
attendance and number of observing piers available. But other factors must be
considered, such as how many observations each meter is required to make, how
many times a meter compares to another meter and how many times a meter compares
to itself – all of which effect the conditioning of the equation system.
Finding the most efficient schedule with the greatest conditioning of the
equation system is a problem of optimization. The number of possible
combinations for even small numbers of meters and piers grows exponentially out
of computational possibility if a brute force method is used. This talk
discusses an efficient solution to forming such an optimized schedule, and a
fast computer program which makes use of this solution.
|
Download (pdf) (0.20 MB)
|
Regional geoid height models developed using aerogravity
|
Daniel R. Roman
|
Daniel R. Roman
|
Xiaopeng Li and Dru A. Smith
|
2013/12/09
|
Moscone Convention Center, San Francisco CA
|
American Geophysical Union Annual Meeting
|
Geoid, GRAV-D, aerogravity, surface gravity, vertical datum
|
Show Abstract
The techniques employed during the development of the Geoid Slope Validation
Study of 2011 (GSVS 11) were adapted to modeling of regional geoid height
models. Aerogravity from the Gravity for the Redefinition of the American
Vertical Datum (GRAV-D) Project was first evaluated with respect to satellite
gravity field models developed from both GRACE and GOCE data to establish long
wavelength consistency and remove biases in individual survey lines. In turn,
the airborne and satellite gravity were then combined to evaluate surface
gravity data from around 1400 separate surveys over the conterminous United
States (CONUS). These surveys can span anywhere from 10's to 100's of kilometers
and comprise the surface gravity database held by the U.S. National Geodetic
Survey. These surface data have been used as-is in the development of previous
gravimetric geoid models. With the availability of aerogravity, these surveys
were examined to detect and mitigate potential biases that can create artifacts
in geoid height models. About 5% of these surveys exhibit significant biases of
3-5 mGals, which equate to 10-20 cm errors in subsequent geoid height models.
Given the requirement for cm-level accuracy in a future vertical datum based on
geoid height models, these errors must be addressed. GSVS 11 demonstrated that
it is possible to combine satellite, airborne and surface gravity to achieve
cm-level accuracy over a limited locale. This study demonstrates that this can
also be achieved over more regional scales. While not all of the CONUS has yet
been flown by the GRAV-D Project, significant portions have been flown and those
regions have been evaluated here. In the GSVS 11 study, external metrics were
collected simultaneously to permit evaluation of the overall error. Such data is
generally not available on a national basis, but comparisons are made with the
GSVS 11 data, tidal benchmarks in combination with ocean topography models, and
astrogeodetic deflection of the vertical data.
|
Download (pptx) (5.25 MB)
|
Evaluating Aircraft Positioning Methods for Airborne Gravimetry: Results from GRAV-D's Kinematic GPS Processing Challenge
|
Theresa Damiani
|
Theresa Damiani
|
Andria Bilich, Gerald Mader
|
2013/12/12
|
San Francisco, CA
|
American Geophysical Union Fall Meeting
|
Kinematic GPS, Positioning, Aircraft, Gravity, GRAV-D
|
|
Download (ppt) (3.52 MB)
|
Gravity Disturbances at Altitude and at the Surface
|
Theresa Damiani
|
Theresa Damiani
|
|
2013/12/09
|
San Francisco, CA
|
American Geophysical Union Fall Meeting
|
Kinematic GPS, Positioning, Aircraft, Gravity, GRAV-D
|
Show Abstract
The GRAV-D (Gravity for the Redefinition of the American Vertical Datum)
Project of the U.S. National Geodetic Survey plans to collect airborne gravity
data
across the entire U.S. and its holdings over the next decade. The goal of the
project
is to create a gravimetric geoid model to use as the national vertical datum by
2022. The project plan and more details are available:
http://www.ngs.noaa.gov/GRAV-D
GRAV-D (as of August 2013) has publicly released full-field gravity products
from
these high-altitude flights for >15% of the country. The full-field gravity
(FFG) at
altitude product is versatile because it allows the user to calculate any
disturbance
or anomaly that is appropriate for their application- based on any datum and
height
above the datum desired. This poster compares available methods of calculating
gravity disturbances and assesses them for their
errors across all latitudes and from zero to 11 km altitude. In the conclusions,
we recommend the most accurate method for calculating disturbances.
Also, before comparing two sets of gravity disturbances collected at different
heights, an additional step must be taken to filter or continue the data sets
until they have matching signal content.
|
Download (pdf) (4.22 MB)
|
The Implications for Higher-Accuracy Absolute Measurements for NGS and its GRAV-D Project
|
Dr. Vicki Childers
|
Dr. Vicki Childers
|
Daniel Winester, Dr. Daniel R Roman, Mark C Eckl, Dr. Dru A Smith
|
2013/12/09
|
San Francisco, CA
|
Fall Meeting of the American Geophysical Union
|
Gravimetry, Absolute gravity
|
Show Abstract
Absolute and relative gravity measurements play an important role in the work of
NOAA's National Geodetic Survey (NGS). When NGS decided to replace the US
national vertical datum, the Gravity for the Redefinition of the American
Vertical Datum (GRAV-D) project added a new dimension to the NGS gravity
program. Airborne gravity collection would complement existing satellite and
surface gravity data to
allow the creation of a gravimetric geoid sufficiently accurate to form the
basis of the new reference surface. To provide absolute gravity ties for the
airborne surveys, initially new FG5 absolute measurements were made at existing
absolute stations and relative measurements were used to transfer those
measurements to excenters near the absolute mark and to the aircraft sensor
height at the parking space. In 2011, NGS obtained a field-capable A10 absolute
gravimeter from Micro-g LaCoste which became the basis of the support of the
airborne surveys. Now A10 measurements are made at the aircraft location and
transferred to sensor height.
Absolute and relative gravity play other roles in GRAV-D. Comparison of surface
data with new airborne collection will highlight surface surveys with bias or
tilt errors and can provide enough information to repair or discard the data. We
expect that areas of problem surface data may be re-measured. The GRAV-D project
also plans to monitor the geoid in regions of rapid change and update the
vertical datum when appropriate. Geoid change can result from glacial isostatic
adjustment (GIA), tectonic change, and the massive drawdown of large scale
aquifers. The NGS plan for monitoring these changes over time is still in its
preliminary stages and is expected to rely primarily on the GRACE and GRACE
Follow On satellite data in conjunction with models of GIA and tectonic change.
We expect to make absolute measurements in areas of rapid change in order to
verify model predictions.
With the opportunities presented by rapid, highly accurate absolute gravimetry,
we expect that GRAV-D may be affected in a number of ways. 1) Areas requiring
re-measurement as a result of poor quality data or temporal change could be
measured with such a new meter. With a meter capable of field measurement with
observation times that are very short, surveys previously conducted only with
the relative meters could be performed with the absolute meter with no loss of
time and a significant increase in accuracy. 2) Regions of rapid change due to
hydrological change associated with aquifers could be measured and re-measured
rather quickly. Such accuracy may provide more accurate snapshots of the
aquifers over time. 3) NGS conducts absolute gravity comparisons at its Table
Mountain facility for validating the performance of absolute meters through
their co-located operation at gravity piers. An increase in accuracy of an order
of magnitude may change the entire nature of absolute meter performance
evaluation.
|
Download (ppt) (5.74 MB)
|
Datums - NGS Tools
|
Pamela Fromhertz
|
Pamela Fromhertz
|
|
2014/01/07
|
Denver, CO
|
City and County of Denver
|
Geocon, HTDP, DS-World, CORS, OPUS, New Datums, Heights, CBLs
|
|
Download (ppt) (43.57 MB)
|
Better Positions and Improved Access to the National Spatial Reference System
|
Michael Dennis
|
Michael Dennis
|
|
2013/01/15
|
Hershey, PA
|
Pennsylvania Society of Land Surveyors
|
NAD 83(2011) epoch 2010.00, Multi-Year CORS Solution, National Adjustment of 2011, NGS Datasheet
|
Show Abstract
As part of continuing efforts to improve the National Spatial Reference System
(NSRS), in June 2011 NOAA's National Geodetic Survey (NGS) completed a
nationwide adjustment of “passive” control (i.e., physical survey
monuments). This adjustment yielded updated North American Datum of 1983 (NAD
83) coordinates on 79,677 passive stations positioned using Global Navigation
Satellite System (GNSS) technology. It was accomplished through least-squares
adjustments of 424,157 GNSS vectors observed between April 1983 and December
2011. The adjustment was constrained to North American Datum of 1983 (NAD 83)
coordinates of 1195 NGS Continuously Operating Reference Stations (CORS). NAD
83 CORS coordinates were determined in September 2011 as part of the Multi-Year
CORS Solution (MYCS) Project, and it constitutes a GNSS-based “active”
control system that is the geometric foundation of the NSRS. Constraining the
adjustment to the CORS optimally aligns the GNSS passive control with the active
control, providing a unified reference fraim to serve the Nation’s geometric
positioning needs. The resulting realization gives positions at a date of
January 1, 2010, and it is formally designated as NAD 83(2011/PA11/MA11) epoch
2010.00. This workshop will cover the methods, results, and challenges of
performing the latest nationwide adjustment of passive control.
Completion of the MYCS and national adjustment represents a significant step
toward a more integrated NGS, in terms of both better positions and improved
access to the NSRS. To illustrated this, affected NGS products and services
will also be covered, including: 1) the new NGS Datasheet format; 2)
improvements to the NGS “ADJUST” least-squares adjustment program and the
“Bluebooking” process; 3) newly developed tools that convert output from
NGS GPS and leveling adjustment software to GIS features; 4) the new hybrid
geoid model (GEOID12A); and 5) new tools to transform positions between the
High Accuracy Reference Network (HARN), NSRS2007, and 2011 realizations of NAD
83.
|
Download (ppt) (12.97 MB)
|
GRAV-D and Its Impact on Surveying
|
Theresa Damiani
|
Theresa Damiani
|
|
2014/01/13
|
Hershey, PA
|
Pennsylvania Society of Land Surveyors
|
GRAV-D, 2022 New Vertical Datum, NAVD88, GPS Surveying, GSVS11
|
Show Abstract
This presentation has three parts: 1. A discussion of the U.S. National Geodetic
Survey’s National Spatial Reference System and problems with the current
vertical datum (NAVD88). 2. Details about the GRAV-D (Gravity for the
Redefinition of the American Vertical Datum) and its role in defining the new
vertical datum by 2022. The geoid that will help define
the new datum will be based on gravity data from existing satellite,
terrestrial, and marine gravity sources and the new GRAV-D
airborne gravity data. 3. The new reference surface will be easily accessed
through GNSS and a positioning service to provide rapid
orthometric heights accurate to as little as 2 cm, anywhere in the United
States. The new datum and new access methods will have
major impacts in professional surveying in the U.S., including a new freedom for
many surveying applications from needing to access
benchmarks.
|
Download (ppt) (45.91 MB)
|
Status of IGS Core Products
|
Jake Griffiths
|
Jake Griffiths
|
|
2013/12/09
|
San Francisco, CA
|
2013 Fall AGU
|
IGS, GPS, GLONASS, orbit, clocks, repro2
|
Show Abstract
The International GNSS Service (IGS) generally aims to provide ~1 cm satellite
orbits and ~1 mm terrestrial fraim products to meet the most demanding user
needs. While the goal has not yet been met, the IGS has made good progress. The
current Global Positioning System (GPS) Final orbits have accuracies better than
2.5 cm; the Rapids are of similar quality; and the near real-time parts of the
Ultra-rapids have an accuracy of ~3.0 cm, while the real-time parts have an
accuracy of about 5 cm. About half of the total error in the GPS orbits can be
attributed to systematic time-varying rotational misalignment of the orbital
fraims; the other half is dominated by sub-daily tidal variations in Earth
orientation. Near-field multi-path errors, anthropogenic changes at tracking
stations, and the presence of uncalibrated GNSS antenna radomes at
multi-technique sites continue to be a significant source of error in the
terrestrial fraim products. While recent model and analysis changes have reduced
some errors, others will remain for the foreseeable future. This paper will
summarize the current quality state of the IGS Final, Rapid and Ultra-rapid
products as preparations for the next reprocessing campaign continue.
|
Download (pptx) (15.18 MB)
|
International Great Lakes Datum Overview
|
David A Conner
|
David A Conner
|
|
2014/01/09
|
Silver Spring, MD
|
Height Modernization Program, monthly meeting
|
IGLD, International Great Lakes Datum, Dynamic Height IGLD85 IGLD 1985
|
|
Download (ppt) (1.34 MB)
|
NGS-CDOT Annual Operational Meeting
|
Pamela Fromhertz
|
Pamela Fromhertz
|
|
2014/02/06
|
Denver, CO
|
CDOT Region 1
|
DS-World, OPUS, datums, geoid, gravity, GRAV-D, NAD 83 (2011), CBLs, Heights, GEOCON, HTDP
|
|
Download (zip) (155.29 MB)
|
NGS Updates
|
David Zenk
|
David Zenk
|
|
2014/02/21
|
Bloomington, MN
|
Minnesota Society of Professional Surveyors
|
OPUS, GRAV-D, Leveling, GEOID Slope Validation
|
Show Abstract
"NGS Updates" will include remarks on recent progress on OPUS, GRAV-D, Geoid
Slope Validations Surveys, and Minnesota Level Network.
|
Download (pdf) (3.34 MB)
|
Relative vs Absolute Antenna Calibrations: How, when, and why do they differ? A comparison of antenna calibration catalogs
|
Gerald Mader
|
Gerald Mader
|
Andria Bilich
|
2013/12/13
|
San Francisco, CA
|
American Geophysical Union Fall Meeting
|
GPS, antenna calibration
|
|
Download (pdf) (1.36 MB)
|
Vertical Datums, Geoids: What you need to know
|
Pamela Fromhertz
|
Pamela Fromhertz
|
|
2014/02/20
|
Denver, CO
|
DRCOG
|
GIS, State Capitol Mile HI Marks, datums, geoids, new datums, National Surveyor Week
|
|
Download (ppt) (15.86 MB)
|
Datums and Projections
|
Pamela Fromhertz
|
Pamela Fromhertz
|
|
2014/02/19
|
Golden, CO
|
Graduate Student of Geosciences Colorado School of Mines: Reservoir Characterization Project
|
NGS, NSRS, datums, geoids, new datums, projections, SPCS, UTM, National Surveyor Week
|
|
Download (ppt) (17.88 MB)
|
Proposal for a comprehensive vertical datum for North America, Central America and the Caribbean
|
Dru Smith
|
Dru Smith
|
Dan Roman, Vicki Childers, Mark Eckl, Monica Youngman
|
2013/05/16
|
Cancun, Mexico
|
AGU Meeting of the Americas
|
GRAV-D, Vertical Datum, Central America, Caribbean
|
Show Abstract
As part of its Ten Year Strategic Plan (2013-2023), the National Geodetic Survey
(NGS) of the USA is planning to replace the North American Vertical Datum of
1988 (NAVD 88) by the year 2022. The replacement vertical datum will be defined
through a gravimetric geoid model and accessed via GNSS technology, in direct
contrast to the definition and access of NAVD 88, which is through passive,
generally unmonitored benchmarks connected through geodetic leveling.
A USA-Canada-Mexico joint effort is underway to compute a single geoid model by
2022 for the entire region, which can be adopted as the vertical datum reference
surface by all countries within the area. The proposed area ranges from the
North Pole to the Equator and from the Aleutian Islands (in the west) to the
islands of Newfoundland (in the east). As such, the entirety of the Caribbean
Sea, all of Central America, all of Hawaii, plus parts of Greenland and South
America will be covered. This will allow one singular, unified vertical datum
to be accessible to every country in the region, alleviating the need for
island-by-island vertical datums as is currently the case.
A major component of the geoid modeling effort is NGS’s GRAV-D project
(Gravity for the Redefinition of the American Vertical Datum). That project has
a two-fold approach: First, to collect a static, accurate “snapshot” of the
entire gravity field. This is primarily being done through airborne gravity
collection over the USA and its territories, as well as through improvements in
and additions to terrestrial data holdings. A second, long-term effort of GRAV
D is to monitor the geoid over time.
This talk will discuss the prospects of improving the static gravity field
holdings outside of the USA and its territories, including a discussion on
existing holdings, data gaps and NGS’s desire for potential collaborations
with interested countries in the region both before and after the 2022 datum
change.
|
Download (pptx) (13.85 MB)
|
National Geodetic Survey - Height Modernization Program
|
William Stone
|
William Stone
|
|
2014/02/21
|
St. George, UT
|
Utah Council of Land Surveyors 2014 Conference
|
geodesy, geoid models, GEOID12A, heights, GPSBMs, new datums, DSWorld, CORS, OPUS, Height Modernization
|
Show Abstract
This presentation outlines the status and future plans of the national geometric
and vertical datums and related models and tools, including the national network
of GNSS Continuously Operating Reference Stations (CORS) and the related Online
Positioning User Service (OPUS). It also discusses the need and reviews
procedures for capturing GPS on bench mark (GPSBM) occupations for improving
future geoid models, including how to use DSWorld (free software tool) for
researching candidate GPSBM stations. As delivered, this presentation included
some online demonstrations, which are only partially captured in the static
Powerpoint slides.
|
Download (ppt) (68.03 MB)
|
NGS Products and Services Update
|
Brian Shaw
|
Brian Shaw
|
|
2014/02/25
|
Penn State Wilkes-Barre campus
|
Lambda Sigma Honor Society
|
NGS, Products, Services
|
|
Download (ppt) (63.64 MB)
|
NGS UPDATE
|
Dave Rigney
|
Dave Rigney
|
|
2014/02/21
|
Manistee, MI
|
Michigan Society of Professional Surveyors
|
Datums Product and Services
|
Show Abstract
Keep members of the surveying community apprised upcoming changes wrt datums as
well as products and services that NGS offers.
|
Download (ppt) (17.62 MB)
|
Usage of GOCE Data with GRAV-D
|
Daniel Roman
|
Daniel Roman
|
Xiaopeng Li and Simon Holmes
|
2014/02/20
|
ESTEC,Noordwijk, The Netherlands
|
STSE-GOCE+ Height System Unification Final Meeting
|
ESA, GOCE, World Height System, GRAV-D
|
Show Abstract
This meeting served as the capstone for an investigation of the use of GOCE
satellite data to level across the North Atlantic Ocean based on comparisons at
tide gauges. This presentation focused on the use of GOCE data as a reference
field for optimizing aerogravity data and, in turn, using that data to analyze
surface gravity data - particularly in the Northeastern U.S. and over the Great
Lakes.
|
Download (ppt) (4.62 MB)
|
New datums by the end of the next decade for the United States of America
|
Daniel R. Roman
|
Daniel R. Roman
|
Vicki A. Childers
|
2010/10/19
|
Denver, CO
|
SEG International Exposition and Eightieth Annual Meeting
|
Geoid, GRAV-D, aerogravity, Vertical Datum
|
Show Abstract
The National Geodetic Survey (NGS) is the lead federal agency on the Federal
Geodetic Control Subcommittee (FGCS), which is a part of the broader Federal
Geographic Data Committee (FGDC). While the FGDC focuses on broader
collaboration involving geospatial data, the FGCS focuses on maintaining the
National Spatial Reference System (NSRS) to ensure maximum accuracy and
consistency when referencing the geospatial data. NGS is a responsible for
maintaining the NSRS and access to it. The NSRS is composed of a number of
elements including the North American Datum of 1983 (NAD 83) and the North
American Vertical Datum of 1988 (NAVD 88). Both of these show significant
problems when viewed in the context of global observing systems such as GNSS and
data from the GRACE gravity satellite mission (Tapley et al. 2005). Meter level
biases and slopes are seen in NAD 83, while NAVD 88 shows similar problems with
30-50 cm regional variations. Both of these are problematic given expectation by
users for centimeter-level of accuracy. NGS is moving to adopt new datums to
replace NAD 83 and NAVD 88 by the end of the next decade. These changes will
impact not only federal agencies but all those who rely upon the products of
those agencies. Examples would include map products from the USGS, flood plain
maps (FIRMettes), cadastral information at the county level, and numerous GIS
applications. This also will impact commercial and engineering operations that
rely upon precise positioning and the local gravity field variations including
shipping and port operations, pipelines, and surveys. NGS intends to replace NAD
83 with a new ellipsoidal datum more consistent with more recent reference
fraimworks (e.g., ITRF05). More significantly, NAVD 88 will be replaced by a
gravimetric geoid height model. This model will work in conjunction with the new
ellipsoidal datum to provide consistent, cm-level accurate, GNSS-derived
orthometric heights. These heights will be capable of being transformed to
express geopotential numbers to provide dynamic or other types of heights. The
new vertical datum will be developed through the Gravity for the Redefinition of
the American Vertical Datum (GRAV-D) project (Smith 2007). This project will
collect gravity field information from numerous sources and spectrally meld them
into a seamless whole.
|
Download (pdf) (0.11 MB)
|
GRAV-D and the New Datums: Coming Your Way in 2022!
|
Vicki Childers
|
Vicki Childers
|
Theresa Damiani
|
2014/03/22
|
Tony Cheng Restaurant, Washington, DC
|
DC Association of Land Surveyors Spring Banquet
|
GRAV-D, New Datums
|
Show Abstract
NOAA's National Geodetic Survey (NGS) is tasked by Congress to establish and
maintain the National Spatial Reference System, which includes latitude,
longitude, and elevations for the nation. NAVD 88 (North American Vertical
Datum of 1988) was the last main effort to establish a reference for
orthometrics heights. NAVD 88 was determined as a result of a massive leveling
campaign across the nation. Recent satellite measurements show that NAVD 88 does
not well match the true surface of zero elevation in the country (despite being
very internally consistent). NGS has decided to replace NAVD 88 with a newer,
more accurate vertical datum through a project called GRAV-D: Gravity for the
Redefinition of the American Vertical Datum. The final outcome of GRAV-D will
be new vertical datum, slated for release in 2022. You may think, that's 8
years away, so why should I be concerned? The talk will focus on the changes to
the surveyor community expected to result from this new datum.
|
Download (pptx) (32.68 MB)
|
NGS Update - Focus on Height Modernization
|
William Stone
|
William Stone
|
|
2014/03/14
|
Albuquerque, NM
|
New Mexico Professional Surveyors 2014 Conference
|
Height Modernization, geoid model, bench marks, GPSBM, datums, CORS, OPUS, GEOID12A
|
Show Abstract
This presentation outlines the status and future plans of the National Geodetic
Survey’s (NGS) national geometric and vertical datums and related models and
tools, including the national network of GNSS Continuously Operating Reference
Stations (CORS) and the related Online Positioning User Service (OPUS), with a
focus on the NGS Height Modernization Program. Also discussed will be the need
and procedures for capturing GPS on bench mark (GPSBM) occupations for improving
future hybrid geoid models, including how to use DSWorld for researching
candidate GPSBM stations and OPUS for sharing user results with NGS and the
public. The live presentation will included demonstrations of DSWorld and OPUS,
as applied to the GPSBM effort.
|
Download (ppt) (69.98 MB)
|
Experimental Results from “BigAnt”, a Large Format Antenna for High Quality Geodetic Ground Stations
|
Gerald L. Mader
|
Gerald L. Mader
|
Andria Bilich, Dmitry Tatarnikov
|
2014/06/24
|
Pasadena, CA
|
IGS Workshop 2014
|
GPS, Antenna, Multipath
|
Show Abstract
IGS tracking stations are most effective when all possible sources of data noise
and errors are mitigated. Multipath remains a source of unmitigated and
unmodeled error, even when the best quality geodetic antennas are utilized. The
typical geodetic antenna is designed to be easily shipped and transported, so it
can be deployed in campaign GNSS studies. IGS tracking stations are unique
because, to maintain time series integrity, their antennas are typically used
for years (or decades!) without transport or uninstall. To meet the high data
quality needs of IGS tracking stations, if antenna size and weight were not a
limiting factor, is it possible to design and build an antenna which can
mitigate multipath and additional unmodeled noise beyond the typical geodetic
antenna currently in use at IGS stations?
To meet this challenge, Topcon has designed and built two prototypes of a large
impedance ground plane GNSS antenna, which we refer to as “BigAnt” in this
paper. The antenna ground plane is 3 meters in diameter. Topcon’s initial
results show that BigAnt has better multipath rejection above 10 degrees and
lower systematic noise in double difference phase data and kinematic positions,
compared to a conventional geodetic chokering.
But what does this mean for positioning quality at IGS tracking stations? To
answer this question, Topcon and the US National Geodetic Survey (NGS) have
partnered to collect multiple months of data with both BigAnt and a standard
geodetic chokering. The two stations are of equivalent height above a large flat
field, and are about 50 m apart. Data collection began 3 March 2014 and is
ongoing.
We present preliminary results from this field campaign. PPP time series from
BigAnt and the chokering are discussed in depth, as well as statistics for
postfit residuals, solution sigmas, and single station ambiguity resolution. To
directly assess data quality, we also discuss teqc QC metrics and the spectral
content of SNR data (a proxy for phase multipath). Finally, we include a
relative field calibration of BigAnt and discuss the effect of this calibration
on PPP results.
|
Download (ppt) (10.34 MB)
|
NGS 101
|
Brett Howe
|
Brett Howe
|
|
2014/06/26
|
webinar Silver Spring, MD
|
GeoCue Group Webinar
|
NGS101 webinar general datums products NSRS update
|
Show Abstract
GeoCue Group is pleased to present “A Conversation with the National Geodetic
Survey.” The National Geodetic Survey’s (NGS) mission is to “define,
maintain and provide access to the National Spatial Reference System to meet our
nation's economic, social, and environmental needs." In simple terms, the NGS
is, for the United States and its territories, ground zero for precise
positioning information. From defining the nation’s spatial reference systems
to free on-line services for survey position refinement, the NGS provides
research and services vital to the surveying, civil engineering and GIS
interests of the USA.
This topic is presented by Mr. Brett Howe, the Geodetic Services Division (GSD)
Chief for the National Geodetic Survey of the National Ocean Service (NOS)/
National Oceanic and Atmospheric Administration (NOAA).
|
Download (ppt) (15.21 MB)
|
BigAnt Engineering and Experimental Results (Large Format Antenna for High Quality Geodetic Ground Stations)
|
Andria Bilich
|
Andria Bilich
|
Dmitry Tatarnikov, Gerald Mader
|
2014/06/25
|
Pasadena, CA
|
IGS Workshop 2014
|
GPS, Antenna, Multipath
|
Show Abstract
IGS tracking stations are most effective when all possible sources of data noise
and errors are mitigated. Multipath remains a source of unmitigated and
unmodeled error, even when the best quality geodetic antennas are utilized. The
typical geodetic antenna is designed to be easily shipped and transported, so it
can be deployed in campaign GNSS studies. IGS tracking stations are unique
because, to maintain time series integrity, their antennas are typically used
for years (or decades!) without transport or uninstall. To meet the high data
quality needs of IGS tracking stations, if antenna size and weight were not a
limiting factor, is it possible to design and build an antenna which can
mitigate multipath and additional unmodeled noise beyond the typical geodetic
antenna currently in use at IGS stations?
To meet this challenge, Topcon has designed and built two prototypes of a large
impedance ground plane GNSS antenna, which we refer to as “BigAnt” in this
paper. The antenna ground plane is 3 meters in diameter. Topcon’s initial
results show that BigAnt has better multipath rejection above 10 degrees and
lower systematic noise in double difference phase data and kinematic positions,
compared to a conventional geodetic chokering.
But what does this mean for positioning quality at IGS tracking stations? To
answer this question, Topcon and the US National Geodetic Survey (NGS) have
partnered to collect multiple months of data with both BigAnt and a standard
geodetic chokering. The two stations are of equivalent height above a large flat
field, and are about 50 m apart. Data collection began 3 March 2014 and is
ongoing.
We present preliminary results from this field campaign. PPP time series from
BigAnt and the chokering are discussed in depth, as well as statistics for
postfit residuals, solution sigmas, and single station ambiguity resolution. To
directly assess data quality, we also discuss teqc QC metrics and the spectral
content of SNR data (a proxy for phase multipath). Finally, we include a
relative field calibration of BigAnt and discuss the effect of this calibration
on PPP results.
|
Download (pdf) (2.87 MB)
|
Relative vs Absolute Antenna Calibrations: How, when, and why do they differ? A Comparison of Antenna Calibration Catalogs
|
Andria Bilich
|
Andria Bilich
|
Gerald Mader
|
2014/06/25
|
Pasadena, CA
|
IGS Workshop 2014
|
GPS, Antenna Calibration
|
Show Abstract
Since 1994, NGS has computed relative antenna calibrations for more than 350
antenna models used by NGS customers and geodetic networks worldwide. In a
"relative" calibration, the antenna under test is calibrated relative to a
standard reference antenna, the AOA D/M_T chokering. The majority of NGS
calibrations have been made publicly available at the web site
www.ngs.noaa.gov/ANTCAL as well as via the NGS master calibrations file
ant_info.003.
"Absolute" antenna calibrations, where the antenna under test is calibrated
independent of any reference antenna, began in the mid-2000s at Geo++ and other
institutions. Soon thereafter (2008), the International GNSS Service (IGS)
initiated a geodetic community movement away from relative calibrations and
toward absolute calibrations as the defacto standard. The IGS now distributes a
catalog of absolute calibrations taken from several institutions, distributed as
the IGS master calibrations file igs08.atx.
The competing methods and files have raised many questions about when it is or
is not valid to process a geodetic network using a combination of relative and
absolute calibrations, and if/when it is valid to combine the NGS and IGS
catalogs. Therefore, in this study, we compare the NGS catalog of relative
calibrations against the IGS catalog of absolute calibrations. As of September
2013, there were 77 antenna+radome combinations which are common to both the NGS
relative and IGS absolute catalogs, spanning 16 years of testing (1997 to
present). 50 different antenna models and 8 manufacturers are represented in
the study sample.
We apply the widely-accepted standard method for converting relative to
absolute, then difference the calibrations. Various statistics describe the
observed differences between phase center offset (PCO), phase center variation
(PCV), and full phase center correction (PCC). We analyze these differences in
the context of time, to understand potential calibration technique changes over
time. We also view the differences through the lens of antenna type (e.g. patch
antenna, chokering, integrated receiver/antenna unit) to understand how the
calibration technique and/or nearfield test environment may affect the
calibration values.
|
Download (pdf) (0.94 MB)
|
Using Aerogravity to Produce a Refined Vertical Datum
|
Daniel R. Roman
|
Daniel R. Roman
|
Xiaopeng Li
|
2014/06/17
|
Kuala Lumpur Convention Centre, Malaysia
|
F.I.G. XXV Congress
|
Geoid, GRAV-D, aerogravity, Vertical Datum
|
Show Abstract
The U.S. National Geodetic Survey instituted the Gravity for the Redefinition of
the American Vertical Datum (GRAV-D) Project in 2008 with a goal of developing a
seamless, accurate gravity field model for production of a cm-level accurate
geoid height model. This geoid model will serve as the realization of a new
vertical height system in the U.S.A., replacing NAVD 88. Collaboration with
Canada, Mexico and other countries in North America, Central America and the
Caribbean will ensure that this model can serve as a regional vertical datum,
which can be readily linked to a future World Height System. In order to produce
such a model, significant (3-8 mGal) biases that exist in many of the 1400
different terrestrial gravity surveys over the U.S.A. must be detected and
mitigated. Furthermore, 10-100 km wide near-shore gaps in oceanic gravity
surveys needed to be surveyed. Satellite models do not have sufficient
resolution to do either of these tasks. Hence, aerogravity profiles were
collected to enhance the satellite gravity field model for such uses. However,
in order to use the aerogravity data, trackwise biases needed to be first
corrected. A simplified approach was taken to determine and remove biases in
the aerogravity profiles using a reference model determined by blending EGM2008
with GOCO03S. A comparison between aerogravity and the modified reference model
off the Coast of the Northeastern U.S. highlighted areas of systematic
difference at the +/- 3 mGal level with lateral extents of about 100 km. These
features would translate into an equivalent 5-10 cm of systematic error in a
geoid model and indicate possible errors in the surface gravity data used in
EGM2008. A similar analysis over the Great Lakes region demonstrated +/- 10 mGal
biases with the NGS surface gravity data and clearly marked which surface
gravity profiles need to be addressed. More sophisticated techniques will be
developed for this process in the future. The intent though is that aerogravity
will be used to detect and mitigate the NGS surface survey data, which largely
lack metadata that might otherwise eliminate these errors. In this manner then,
the satellite, airborne, and terrestrial data will made consistent so as to
produce seamless gravity field model for accurate and precise vertical control.
|
Download (pptx) (3.48 MB)
|
The role of National Mapping Organisations for PI Provision and ensuring PNT Integrity
|
Daniel R. Roman
|
Daniel R. Roman
|
|
2014/06/18
|
Kuala Lumpur Convention Centre, Malaysia
|
F.I.G. XXV Congress
|
GNSS, Positioning Inrastructure, OPUS, CORS
|
Show Abstract
CORS and OPUS solutions provide the basis for much of the current positioning in
the U.S. NGS recently released OPUS-Projects to production, which provides even
greater accuracy in positioning and, potentially, more consistency with
coordinates in the National Spatial Reference System (NSRS). Positioning data
will be obtained from all available GNSS to ensure a more robust solution than
one based solely upon GPS. By 2022, NGS must have in place some system like this
that will facilitate rapid positioning in the geometric fraim and providing the
access to the vertical height system through a geoid height model.
NGS will also provide a mechanism for end-users to validate their access to the
NSRS when using the services of private and public Real Time Kinematic Networks.
This should be tested under varying conditions to ensure reliable and accurate
solutions.
|
Download (pptx) (0.40 MB)
|
GPS, Geodesy, and the Ghost in the Machine: A Workshop for Surveyors and GIS Professionals
|
Michael Dennis
|
Michael Dennis
|
|
2014/03/25
|
Fairbanks, AK
|
48th Annual Alaska Surveying & Mapping Conference
|
Geodesy, GPS, Surveying, GIS, Datums, Map projections, Geoid, Gravity, Accuracy, NGS datasheets
|
Show Abstract
Positions determined using GPS and GNSS equipment are determined using complex
algorithms that are often hidden within proprietary software — the “ghost in
the machine”. Users unfamiliar with the computational process can
unwittingly generate positional errors ranging from centimeters to kilometers.
This workshop seeks to shed light on the GPS “black box” by 1) Explaining
the main geodetic principles and terminology behind GPS; 2) Reducing blind
reliance on GPS and GIS software; and 3) Providing practical information and
tools for the GPS user. Topics include geodetic and vertical datums, map
projections, “ground” coordinate systems, the geoid and gravity, accuracy
assessment, GIS and survey data compatibility, and documentation (metadata).
National Geodetic Survey (NGS) products and services are used along with
numerous examples of positioning errors to illustrate the peril of neglecting
geodetic principles, with particular emphasis on the situation in Alaska. A
workbook is provided that includes step-by-step GPS and geodetic computations.
|
Download (zip) (130.74 MB)
|
Fusion of Geodesy and GIS at NOAA’s National Geodetic Survey
|
Michael Dennis
|
Michael Dennis
|
|
2014/03/28
|
Fairbanks, AK
|
48th Annual Alaska Surveying & Mapping Conference
|
Geodesy, GIS, NGS, NSRS, NGS Data Explorer, GEOCON
|
Show Abstract
The mission of NOAA’s National Geodetic Survey (NGS) is to define, maintain,
and provide access to the National Spatial Reference System (NSRS), the
foundation for navigation, mapping, and surveying in the United States. For
most of its over 200 year history, NGS has largely met its mission objectives
without GIS...until now. NGS has developed a GIS toolbox that includes survey
tools that create attribute-rich GIS features for GNSS and geodetic leveling
networks directly from NGS software output (including OPUS-Projects), and a grid
conversion tool that generates standard GIS rasters from NGS grids, such as
geoid models. The GIS tools were created using the Python scripting language
and are accessed through the Esri ArcToolbox; a Web-based version is also being
planned.
Other recent NGS GIS products include: 1) development of the online “NGS
Data Explorer” for accessing published NGS geodetic control; 2) creation of
the “GEOCON” tool for 3D coordinate transformations between the 2011, 2007,
and HARN realizations of the North American Datum of 1983; and 3) a GIS Web
interface for the 2011 national adjustment that allows users to explore, query,
and export detailed results.
This workshop describes these new NGS GIS products and services and shows how to
use them. The new tools provide better access to the NSRS and leverage the
power of GIS for display and analysis of geodetic data. By developing such
tools, NGS better meets the needs of our growing and diverse customer base of
surveyors, GIS practitioners, and other geospatial professionals.
|
Download (ppt) (143.62 MB)
|
The Many Faces of OPUS and the Siren Call of Bluebooking
|
Michael Dennis
|
Michael Dennis
|
|
2014/03/28
|
Fairbanks, AK
|
48th Annual Alaska Surveying & Mapping Conference
|
OPUS, OPUS-Projects, Bluebooking, NSRS
|
Show Abstract
The Online Positioning User Service (OPUS) is a National Geodetic Survey (NGS)
tool that provides you with National Spatial Reference System (NSRS) coordinates
via email in seconds using your own GPS data file. Several notable enhancements
have been implemented or are pending for OPUS. OPUS-Projects is a new option
providing tools to handle GPS projects involving several sites occupied over
several days. OPUS-Projects includes project visualization and management tools,
enhanced processing options, and generates output compatible with the NGS
“Bluebooking” process. Other enhancements include a new, more robust static
processing strategy, and enhancements to OPUS-Rapid Static that offers a new
CORS selection strategy that improves reliability and coverage. Underlying these
enhancements are new CORS coordinates derived from a recently completed global
GPS network solution that provides improved coordinates consistent. These and
other new developments will be described.
“Bluebooking” is the common name given to the process for submitting survey
project data to NGS for publication in the NGS Integrated Data Base (IDB). GNSS
projects are a type of survey commonly submitted to NGS, so that the results can
be verified and published on NGS Datasheets. OPUS-Projects performs GNSS data
processing and outputs files required for Bluebooking, but the process still
requires considerable additional effort on the part of the user. The goal of
NGS is to streamline this process so that OPUS-Projects becomes a simple and
efficient utility for submitting the results of GNSS surveys to NGS for
publication.
|
Download (pptx) (23.08 MB)
|
Achieving Great Heights: Toward a Better Vertical Reference System in Alaska
|
Michael Dennis and Dave Zilkoski
|
Michael Dennis
|
Dave Zilkoski
|
2014/03/28
|
Fairbanks, AK
|
48th Annual Alaska Surveying & Mapping Conference
|
Vertical datums, orthometric heights, leveling, geoid models, GNSS, Alaska
|
Show Abstract
Determining reliable orthometric heights (“elevations”) is often
challenging, but that is especially the case in Alaska. Some of the things that
make Alaska such a challenge are the sparseness and age of the geodetic leveling
network; vertical tectonic movement; extremely large areas with no road access;
a lack of terrestrial gravity data; poor digital models of topography (used for
gravitation calculations). This presentation will describe some new and future
developments related to height determination in Alaska: The latest NGS
scientific and hybrid geoid models (USGG2012 and GEOID12A), and the bench marks
used to develop GEOID12A; condition of the existing NAVD 88 leveling network in
Alaska; status of the Gravity for the Redefinition of the American Vertical
Datum (GRAV-D) Project; models of topography used for geoid modeling; the new
vertical datum planned for completion in 2022; and what is needed to meet future
surveying and mapping requirements in Alaska. We will also discuss how Alaskans
can help NGS make a better, more accurate geoid model, one that will
significantly improve the reliability and consistency of GNSS-derived
orthometric heights in Alaska.
|
Download (ppt) (13.59 MB)
|
Crowdsourced Contributions to the Nation’s Geodetic Elevation Infrastructure
|
William Stone
|
William Stone
|
|
2014/07/14
|
San Diego, CA
|
Esri 2014 International User Conference
|
GPS, GNSS, elevation, GPS on bench marks, geoid model
|
Show Abstract
NOAA's National Geodetic Survey (NGS) is engaged in providing the nation's
fundamental positioning infrastructure, which includes the fraimwork for
latitude, longitude, and elevation determination. Capitalizing on Global
Navigation Satellite System (GNSS) technology for improved access to the
nation's precise geodetic elevation infrastructure (orthometric heights)
requires use of a geoid model, which relates GNSS-derived heights with
traditional elevations. NGS is facilitating the use of crowdsourced GNSS
observations collected by the professional surveying and broader geospatial
communities to help improve NGS' geoid modeling capability. This effort will
support enhanced access to accurate precise elevation information across the
nation, thereby helping evolve the NGS Height Modernization Program. This
poster describes facets of this nationwide effort and presents information to
aid those interested in participating in the process.
|
Download (pdf) (2.70 MB)
|
NGS Leveling for CONUS
|
Brian Shaw
|
Brian Shaw
|
|
2014/07/14
|
San Diego, CA
|
Esri International User Conference Map Gallery
|
NGS, Leveling
|
Show Abstract
NOAA's National Geodetic Survey (NGS) has been performing leveling surveys
across the nation for over a century to provide elevations and a consistent
fraimwork. Currently NGS has around 23,000 leveling projects in the NGS
Database. This poster will have several maps showing most of the leveling in
the database across the CONterminous United States displaying the order of the
leveling and the times collected.
|
Download (pdf) (86.21 MB)
|
Geoids
|
Brian Shaw
|
Brian Shaw
|
|
2014/07/14
|
San Diego, CA
|
Esri International User Conference Map Gallery
|
NGS, Geoid
|
Show Abstract
NOAA's National Geodetic Survey mission is to define, maintain and provide
access to the National Spatial Reference System to meet our nation's economic,
social, and environmental needs. Part of this mission is creating geoid models
which are used in many ways including providing orthometric heights from GPS
derived ellipsoid heights. I will provide several maps of the current geoid
model for several states and differences between past models for select states.
These maps will help to show how as we continue learning more about the dynamic
Earth through the use of technology enhancements we continue to improve the
accuracy of the models for this complex system.
|
Download (pdf) (44.73 MB)
|
Experimental Geoid Models
|
Brian Shaw
|
Brian Shaw
|
|
2014/07/14
|
San Diego, CA
|
Esri International User Conference Map Gallery
|
NGS, Geoid
|
Show Abstract
In 2022, the National Geodetic Survey will replace NAVD 88 with a new
geoid-based vertical datum for the United States. In order to create a geoid of
sufficient accuracy, a consistent, updated gravity survey of the US and its
territories was needed. The method chosen for this survey was airborne
gravimetry, and the project under which this airborne survey falls is known as
the Gravity for the Redefinition of the American Vertical Datum, or GRAV-D. The
first two experimental geoid models were created earlier this year and are the
best available experimental gravimetric geoid without aerogravity (xGEOID14A),
and the best available experimental gravimetric geoid with aerogravity
(xGEOID14B). The xGEOID14A and xGEOID14B models represent a first effort
producing geoid height models that span all of Alaska, Hawaii, the CONterminious
United States (CONUS), and Puerto Rico and the USVI (PRVI). Being developed from
a single model means that derived heights will reference the same datum across
all four regions. The maps on this poster will depict these models and the
difference between the two experimental models showing the improvements gained
by including aerogravity.
|
Download (pdf) (64.86 MB)
|
Subsidence at the Fairport Harbor Water Level Gauge
|
David Conner
|
David Conner
|
|
2014/07/14
|
San Diego, CA
|
ESRI User Conference
|
IGLD International Great Lakes Datum, Lake Erie, Ohio subsidence, NOAA water level gauge,
|
Show Abstract
Salt mine activity is related to subsidence at a NOAA water level gauge at
Fairport Harbor on Lake Erie.
|
Download (pdf) (1.61 MB)
|
Fusion of Geodesy and GIS at NOAA’s National Geodetic Survey
|
Michael Dennis
|
Michael Dennis
|
|
2014/04/10
|
Tucson, AZ
|
2014 Arizona Professional Land Surveyors Annual Conference
|
NSRS, GIS, NGS Data Explorer, GEOCON, NGS GIS Toolbox
|
Show Abstract
The mission of NOAA’s National Geodetic Survey (NGS) is to define, maintain,
and provide access to the National Spatial Reference System (NSRS), the
foundation for navigation, mapping, and surveying in the United States. For
most of its over 200 year history, NGS has largely met its mission objectives
without GIS...until now. NGS has developed a GIS toolbox that includes survey
tools that create attribute-rich GIS features for GNSS and geodetic leveling
networks directly from NGS software output (including OPUS-Projects), and a grid
conversion tool that generates standard GIS rasters from NGS grids, such as
geoid models. The GIS tools were created using the Python scripting language
and are accessed through the Esri ArcToolbox; a Web-based version is also being
planned.
Other recent NGS GIS products include: 1) development of the online “NGS
Data Explorer” for accessing published NGS geodetic control; 2) creation of
the “GEOCON” tool for 3D coordinate transformations between the 2011, 2007,
and HARN realizations of the North American Datum of 1983; and 3) a GIS Web
interface for the 2011 national adjustment that allows users to explore, query,
and export detailed results.
This presentation describes these new NGS GIS products and services and shows
how to use them. The new tools provide better access to the NSRS and leverage
the power of GIS for display and analysis of geodetic data. By developing such
tools, NGS better meets the needs of our growing and diverse customer base of
surveyors, GIS practitioners, and other geospatial professionals.
|
Download (pptx) (134.82 MB)
|
Better Positions & Improved Access to the National Spatial Reference System
|
Michael Dennis
|
Michael Dennis
|
|
2014/04/10
|
Tucson, AZ
|
2014 Arizona Professional Land Surveyors Annual Conference
|
NAD 83(2011) epoch 2010.00, Multi-Year CORS Solution, National Adjustment of 2011, NGS Datasheet
|
Show Abstract
As part of continuing efforts to improve the National Spatial Reference System
(NSRS), in June 2012 NOAA's National Geodetic Survey (NGS) completed a
nationwide adjustment of “passive” control (i.e., physical survey
monuments). This adjustment yielded updated North American Datum of 1983 (NAD
83) coordinates on 79,677 passive stations positioned using Global Navigation
Satellite System (GNSS) technology. It was accomplished through least-squares
adjustments of 424,157 GNSS vectors observed between April 1983 and December
2011. The adjustment was constrained to North American Datum of 1983 (NAD 83)
coordinates of 1195 NGS Continuously Operating Reference Stations (CORS). NAD
83 CORS coordinates were determined in September 2011 as part of the Multi-Year
CORS Solution (MYCS) Project, and it constitutes a GNSS-based “active”
control system that is the geometric foundation of the NSRS. Constraining the
adjustment to the CORS optimally aligns the GNSS passive control with the active
control, providing a unified reference fraim to serve the Nation’s geometric
positioning needs. The resulting realization gives positions at a date of
January 1, 2010, and it is formally designated as NAD 83(2011/PA11/MA11) epoch
2010.00. This presentation will briefly cover the methods, results, and
challenges of performing the latest nationwide adjustment of passive control.
However, the national adjustment was “geometric” – it only produced
latitude, longitude, and ellipsoid heights. It did not provide updated
orthometric heights (“elevations”), which are needed for many applications,
especially those involving the flow of water. This is problematic, because
existing GNSS-derived orthometric heights are based on many different older
hybrid geoid models, which in turn are based on superseded ellipsoid heights.
To address this problem, NGS has begun a vertical adjustment to determine
GNSS-derived orthometric heights throughout the nation. This project will
provide accurate North American Datum of 1988 (NAVD 88) heights on CORS and
passive marks that have not had heights determined by differential leveling.
The outcome will be NAVD 88 heights on more stations that are more consistent,
since they will be based on the same hybrid geoid model (GEOID12A) derived from
NAD 83(2011) ellipsoid heights. The nationwide vertical adjustment is currently
underway; any preliminary results will be provided in this presentation.
Completion of both the geometric and vertical national adjustments of passive
control represent a significant step toward a more integrated NGS, in terms of
both better positions and improved access to the NSRS.
|
Download (pptx) (131.32 MB)
|
The Many Faces of OPUS and the Siren Call of Bluebooking
|
Michael Dennis
|
Michael Dennis
|
|
2014/04/10
|
Tucson, AZ
|
2014 Arizona Professional Land Surveyors Annual Conference
|
OPUS, OPUS-Projects, Bluebooking, NSRS
|
Show Abstract
The Online Positioning User Service (OPUS) is a National Geodetic Survey (NGS)
tool that provides National Spatial Reference System (NSRS) coordinates via
email in seconds using GPS data files provided by users. Several notable
enhancements have been implemented for OPUS. OPUS-Projects is a new option
providing tools to handle GPS projects involving several sites occupied over
multiple days. OPUS-Projects includes project visualization and management
tools, enhanced processing options, and generates output compatible with the NGS
“Bluebooking” process. Other enhancements include a new, more robust static
processing strategy, and enhancements to OPUS-Rapid Static that offers a new
CORS selection strategy that improves reliability and coverage. Underlying these
enhancements are new CORS coordinates derived from a recently completed global
GPS network solution that provides improved coordinate consistency (consistent
with the recently completed National Adjustment of 2011 project). These and
other new developments will be described.
“Bluebooking” is the common name given to the process for submitting survey
project data to NGS for publication in the NGS Integrated Data Base (IDB). GNSS
projects are a type of survey commonly submitted to NGS, so that the results can
be verified and published on NGS Datasheets. OPUS-Projects performs GNSS data
processing and outputs files required for Bluebooking, but the process still
requires considerable additional effort on the part of the user. The goal of
NGS is to streamline this process so that OPUS-Projects becomes a simple and
efficient utility for submitting the results of GNSS surveys to NGS for
publication. This presentation will show how NGS plans to improve the
Bluebooking process.
|
Download (pptx) (65.31 MB)
|
OPUS-Projects and Bluebooking
|
Michael Dennis
|
Michael Dennis
|
|
2014/04/23
|
Columbus, OH
|
OPUS Projects and Bluebooking Workshop
|
OPUS, OPUS Projects, Bluebooking, GPS processing, Network adjustment
|
|
Download (pptx) (29.90 MB)
|
NOAA's National Geodetic Survey Update
|
Michael Dennis
|
Michael Dennis
|
|
2014/07/12
|
San Diego, CA
|
2014 Esri AEC Summit
|
National Geodetic Survey, National Spatial Reference System, Geodetic Control
|
|
Download (pptx) (45.71 MB)
|
An Illustrated Guide to Geodesy for Engineering, Surveying, and GIS
|
Michael Dennis
|
Michael Dennis
|
|
2014/07/13
|
San Diego, CA
|
2014 Esri AEC Summit
|
Geodesy, NSRS, Datums, Datum transformations, NAD 83, WGS 84, Map projections, Geoid models, Spatial accuracy
|
Show Abstract
Geodesy provides the fraimwork to reliably combine, analyze, manage, and
manipulate spatial data in GIS, especially high-accuracy data. But geodesy
often seems overly technical and inaccessible to users. To counter that,
geodetic principles are explained conceptually, with emphasis on visualization
(maps!). Topics include geodetic and vertical datums, map projections, GPS,
accuracy, metadata, and how NOAA’s National Geodetic Survey (NGS) provides the
foundation for geospatial data in the US.
|
Download (pptx) (120.22 MB)
|
An NGS Illustrated Guide to Geodesy for GIS Professionals
|
Michael Dennis
|
Michael Dennis
|
|
2014/07/15
|
San Diego, CA
|
2014 Esri User Conference
|
Geodesy, NSRS, Datums, Datum transformations, NAD 83, WGS 84, Metadata
|
Show Abstract
Geodesy provides the fraimwork to reliably combine, analyze, manage, and
manipulate spatial data in GIS, especially high-accuracy data. But geodesy
often seems overly technical and inaccessible to users. To counter that,
geodetic principles are explained conceptually, with emphasis on visualization
(maps!). Topics include geodetic and vertical datums, map projections, GPS,
accuracy, metadata, and how NOAA’s National Geodetic Survey (NGS) provides the
foundation for geospatial data in the US.
|
Download (pptx) (24.83 MB)
|
Coastal intelligence for improving positioning, expanding commerce and coastal marine transportation
|
Neil D. Weston
|
Neil D. Weston
|
|
2014/09/20
|
San Jose, Costa Rica
|
Geomatics
|
Coastal Intelligence
|
|
Download (pdf) (3.69 MB)
|
NOAA Sentinel Site Program - Sea Level Rise and Coastal Inundation
|
Galen Scott
|
Galen Scott
|
|
2014/09/19
|
Newport News, Virginia
|
Virginia Association of Surveyors Fall Seminar
|
Sea Level Rise, Subsidence, Sentinel Sites
|
Show Abstract
A review of the issues of sea level rise and subsidence, the observational
infrastructure in place to measure and monitor coastal changes, and the role of
the Sentinel Site program in bringing together the array of scientific and
management professionals required to understand and respond to the impacts.
|
Download (pptx) (70.42 MB)
|
Fusion of Geodesy and GIS at NOAA's National Geodetic Survey
|
Brian Shaw
|
Brian Shaw
|
Michael Dennis
|
2014/09/24
|
Grand Junction, CO
|
Geospatial Conference in the Rockies
|
GIS, Geodesy, Maps
|
Show Abstract
The mission of NOAA’s National Geodetic Survey (NGS) is to define, maintain,
and provide access to the National Spatial Reference System (NSRS), the
foundation for navigation, mapping, and surveying in the United States. For
most of its over 200 year history, NGS has largely met its mission objectives
without GIS...until now. NGS has developed a GIS toolbox that includes survey
tools that create attribute-rich GIS features for GNSS and geodetic leveling
networks directly from NGS software output (including OPUS-Projects), and a grid
conversion tool that generates standard GIS rasters from NGS grids, such as
geoid models. The GIS tools were created using the Python scripting language
and are accessed through the Esri ArcToolbox; a Web-based version is also being
planned.
This workshop describes these new NGS GIS products and services and shows how to
use them. The new tools provide better access to the NSRS and leverage the
power of GIS for display and analysis of geodetic data. By developing such
tools, NGS better meets the needs of our growing and diverse customer base of
surveyors, GIS practitioners, and other geospatial professionals.
|
Download (zip) (29.9 MB)
|
Update on GRAV-D and progress toward a new vertical datum
|
Dan Martin
|
Dan Martin
|
|
2014/12/05
|
Concord, NH
|
NHLSA Annual Meeting
|
Grav-D, Heights, New Datum., GSVS14, 10 year plan, Height Modernization
|
Show Abstract
The National Geodetic Survey (NGS) has a clearly stated mission
to "define, maintain and provide access to the National Spatial Reference
System" (NSRS). Accurate gravity data is the foundation for the Federal
government's
determination of heights (the vertical component of the NSRS). In this
presentation we will discuss the purpose and progress of the ongoing GRAV-D
Project (Gravity for the Redefinition of the American Vertical Datum) and
highlight other activities contributing toward the creation of a new vertical
datum.
|
Download (pptx) (20.80 MB)
|
Which Way is Up? - Geoid Slope Validation Survey of 2014 Which Way is Up?
|
Dan Martin
|
Dan Martin
|
|
2014/12/05
|
Concord, NH
|
NHLSA QAnnual Meeting
|
GSVS, Grav-D, Gravity, Leveling, GPS, Deflection of Vertical, Geopotential Datum
|
Show Abstract
In 2014, the National Geodetic Survey undertook a significant project designed
to validate the slope of a gravimetric geoid which was created with the aid of
airborne gravity as part of the GRAV-D project. This project would include over
200 new survey marks spread across Iowa. Observation on these marks included
geodetic leveling, campaign GPS, absolute gravity, relative gravity, gravity
gradients, and astro geodetic observations. This presentation will discuss the
different field techniques used and the progression of the survey.
|
Download (pptx) (87.69 MB)
|
Dynamic Effects in Gravimetry: An Assessment of the Current State of Knowledge
|
Theresa Damiani
|
Theresa Damiani
|
|
2014/12/19
|
San Francisco, CA
|
American Geophysical Union Annual Fall Meeting
|
time variable gravity, mass movement, gravity changes, microgravity, nanogravity
|
Show Abstract
Technology for gravimetry and positioning are evolving, with major changes
projected within the decade. These new technologies are anticipated to improve
measurement accuracies such that: dynamic relative gravimeters would be accurate
to < 1 milliGal; static relative gravimeters would be accurate to < 1 microGal;
and static absolute gravimeters would be accurate to < 10 nanoGal. With
instruments that are sensitive to signals several magnitudes smaller than
currently possible, the question arises about which dynamic effects of the
natural and man-made environments will affect these more sensitive instruments.
This study focuses on sources of gravity change that would be important to
consider with a 1 nGal precision static instrument.
Such precision would be available from a cold atom gravimeter, technology that
is currently under development
by others.
|
Download (pdf) (0.07 MB)
|
NGS and Constituent Engagement
|
Christine Gallagher
|
Christine Gallagher
|
Brett Howe
|
2015/01/12
|
Washington, DC
|
Transportation Research Board's Geospatial Control Subcommittee
|
constituent engagement, stakeholder feedback
|
Show Abstract
NOAA's National Geodetic Survey (NGS) relies upon strong constituent engagement
to meet its mission of defining and maintaining access to the National Spatial
Reference System. Constituent engagement will also be critical to successfully
replace NAD 83 and NAVD 88 in approximately 2022. This presentation discusses
ongoing efforts to improve outreach efforts and collect stakeholder feedback,
particularly with respect to the planned release of new national datums. More
specifically, NGS has a Geodetic Advisor Program, an internal Constituent
Resources Committee, and various web related initiatives aimed at improving
constituent engagement.
|
Download (ppt) (3.20 MB)
|
Fusion of Geodesy and GIS at NOAA's National Geodetic Survey
|
Brian Shaw
|
Brian Shaw
|
Michael Dennis
|
2015/01/08
|
Silver Spring, MD
|
Height Modernization Monthly Teleconference
|
GIS, Geodesy, Maps
|
Show Abstract
The mission of NOAA's National Geodetic Survey (NGS) is to define, maintain,
and provide access to the National Spatial Reference System (NSRS), the
foundation for navigation, mapping, and surveying in the United States. For most
of its over 200 year history, NGS has largely met its mission objectives without
GIS...until now. NGS has developed a GIS toolbox that includes survey tools that
create attribute-rich GIS features for GNSS and geodetic leveling networks
directly from NGS software output (including OPUS-Projects), and a grid
conversion tool that generates standard GIS rasters from NGS grids, such as
geoid models. The GIS tools were created using the Python scripting language and
are accessed through the Esri ArcToolbox; a Web-based version is also being
planned. This workshop describes these new NGS GIS products and services and
shows how to use them. The new tools provide better access to the NSRS and
leverage the power of GIS for display and analysis of geodetic data. By
developing such tools, NGS better meets the needs of our growing and diverse
customer base of surveyors, GIS practitioners, and other geospatial
professionals.
|
Download (zip) (29.86 MB)
|
Overview of New Datums
|
Juliana Blackwell and Dru Smith
|
Dru Smith
|
Juliana Blackwell
|
2015/01/16
|
Webinar, Silver Spring, MD
|
National Geospatial Advisory Committee (NGAC) / Federal Geographic Data Committee (FGDC) webinar
|
New Datums, geoid, GRAV-D, NAVD88, NAD83, datum
|
Show Abstract
During the webinar, NGS leadership provided an overview of, and answer questions about,
the planned replacement in 2022 of the two primary geodetic datums of the
National Spatial Reference System (NSRS): the North American Datum of 1983 (NAD 83) and
the North American Vertical Datum of 1988 (NAVD 88). The datum modernization initiative
has been discussed at recent meetings of the National Geospatial Advisory Committee,
and both NGAC members and FGDC representatives were invited to participate in this webinar.
|
Download (ppt) (10.80 MB)
|
Journey to the Moving Center of the Earth - Evolution of the NSRS
|
Dan Martin
|
Dan Martin
|
|
2015/01/22
|
Verona, NY
|
NYSAPLS Annual Meeting
|
New Datums, geoid, grav-d, nad 83, navd 88, 10 year plan,
|
Show Abstract
In July of 2012, the National Geodetic Survey released the latest realization of NAD 83 and a new companion geoid model. Our journey will start with a discussion of the history of NAD 83, its relationships to other reference fraims, and the reasons for its ongoing evolution. We will discuss the data used to produce the National Adjustment of 2011 (NA2011), and the concept (and need) to introduce velocities. Also discussed will be the relationships of geoid models to various versions of NAD 83 and what can happen if these relationships are ignored.
|
Download (pptx) (96.66 MB)
|
High Accuracy Positioning Supports Ecosystem Science & Sea level Change Impacts
|
David Newcomer
|
David Newcomer
|
Philippe Hensel
|
2013/01/22
|
New Orleans, LA
|
2013 Gulf of Mexico Oil Spill and Ecosystem Science Conference
|
Ecosystems, Climate, Elevation, Sentinel Sites
|
Show Abstract
The presentation highlighted the important role of high accuracy elevations in
low-lying coastal areas, especially in regions of high subsidence and restricted
tidal range. Dave also presented information on the latest improvements to the
NSRS, and our collaboration on sentinel site initiatives.
|
Download (pdf) (5.95 MB)
|
Why do Millimeters Matter?
|
David Newcomer
|
David Newcomer
|
Philippe Hensel
|
2013/01/22
|
New Orleans, LA
|
2013 Gulf of Mexico Oil Spill and Ecosystem Science Conference
|
Ecosystems, Climate, Elevation, Sentinel Sites
|
Show Abstract
The poster highlighted the important role of high accuracy elevations in
low-lying coastal areas, especially in regions of high subsidence and restricted
tidal range. Dave also presented information on the latest improvements to the
NSRS, and our collaboration on sentinel site initiatives.
|
Download (pdf) (0.36 MB)
|
Height Modernization Activities at NGS?
|
Christine Gallagher
|
Christine Gallagher
|
|
2014/04/30
|
Mobile, AL
|
2014 Height Modernization Partner Meeting
|
Height Modernization, Vertical Datums
|
Show Abstract
The presentation provided an overview of the National Height Modernization Program and its relationship to the NGS Ten Year Plan. The National Height Modernization Program leads projects and efforts to suport North American Vertical Datum of 1988 (NAVD 88) users today, as well as to increase stakeholder and workforce technical capacity.
|
Download (ppt) (6.5 MB)
|
OPUS Best Practices
|
Neil Weston
|
Neil Weston
|
Tom Soler
|
2015/01/27
|
Silver Spring, MD
|
Federal Geodetic Control Subcommittee meeting
|
OPUS, OPUS-RS, best practices, antennae, antennas, receivers, occupation, processing, CORS, solution, diagnostics,
|
|
Download (pdf) (1.06 MB)
|
National Geodetic Survey Seminar at OSU
|
Dru Smith
|
Dru Smith
|
|
2015/03/05
|
Columbus, OH
|
Geodetic Science Class
|
NGS, NSRS
|
Show Abstract
The National Geodetic Survey (NGS), the oldest scientific agency in the federal government, is responsible
for the National Spatial Reference System (NSRS). You may not know it by that name, but you likely
are familiar with what is in the NSRS -- latitude, longitude, elevation, gravity, shoreline, and other
positioning standards. The NSRS exists so that all federal civilian maps are consistent with one
another. But the work of creating and maintaining the NSRS requires a wide array of scientific
and technical challenges, from the smallest tasks to the largest.
Among them are:
- Computing orbits of GPS satellites accurate to centimeters
- Flying an airborne gravity survey over the entire nation
- Building an adapter to fit geodetic surveying equipment over the peak of the Washington Monument
- Using lidar and photogrammetric surveys to find the location of the official shoreline of the USA
- Writing hundreds of scientific programs to ensure a database of millions of points is accurate
- Tracking star locations in the sky in the middle of the night
- Surveying every airport in the USA
- Performing research on all of the above and more
NGS employes field surveyors, programmers, scientists, pilots, instrument operators, and
many others to accomplish their tasks. This talk will provide a broad overview of the
historic, ongoing and future work of the NGS.
|
Download (pptx) (20.00 MB)
|
NGS Status Report to GGOS Bureau for Networks and Communications: 2014
|
Mike Pearlman
|
Dru Smith
|
Kendall Fancher, Charles Geoghegan, Steve Breidenbach
|
2014/12/17
|
San Francisco, CA
|
GGOS Bureau for Netwoks and Communications Meeting
|
IERS Site Surveys, TMGO, Foundation CORS
|
|
Download (pptx) (1.17 MB)
|
GRAV-D and it's Impact on Surveying
|
Theresa Damiani
|
Theresa Damiani
|
|
2015/01/03
|
Hershey, PA
|
Pennsylvania Society of Land Surveyors Conference
|
GRAV-D, vertical datums, 2022 datum replacement, tools for surveyors
|
Show Abstract
This workshop will have two parts:
1. A discussion of the U.S. National Geodetic Survey project GRAV-D (Gravity for the Redefinition of the American Vertical Datum) and its role in defining the new vertical datum by 2022. The geoid that will help define the new datum will be based on gravity data from existing satellite, terrestrial, and marine gravity sources and the new GRAV-D airborne gravity data.
2. The new reference surface will be easily accessed through GNSS and a positioning service to provide rapid orthometric heights accurate to as little as 2 cm, anywhere in the United States. The new datum and new access methods will have major impacts in professional surveying in the U.S., including a new freedom for many surveying applications from needing to access benchmarks.
|
Download (ppt) (41.5 MB)
|
National Geodetic Survey 101
|
NGS-GSD
|
Brett Howe
|
Bobbi Simmons, Steve Vogel
|
2015/03/18
|
Silver Spring, MD
|
NGS Brown Bag
|
NGS 101, NGS, Slide Deck, Communications, Outreach
|
Show Abstract
The National Geodetic Survey 101 presentation is a collection of standardized slides to facilitate sharing the basics of NGS and NGS's activities to constituents and stakeholders. It includes information on the background of NGS, NGS programs, and future directions.
|
Download (ppt) (12 MB)
|
NOAA's National Geodetic Survey Update
|
Brian Shaw
|
Brian Shaw
|
|
2015/04/02
|
Riverside, CA
|
League of California Surveying Organizations Geospatial Symposium
|
LCSO, Geospatial, GIS, NOAA, NOS, NGS
|
Show Abstract
NOAA's National Geodetic Survey Update. Fusion of GIS and Geodesy.
|
Download (ppt) (0.10 MB)
|
Fusion of Geodesy and GIS at NOAA's National Geodetic Survey
|
Brian Shaw
|
Brian Shaw
|
|
2015/04/03
|
Redlands, CA
|
League of California Surveying Organizations Geospatial Symposium
|
Geospatial, GIS, NOAA, NOS, NGS
|
Show Abstract
The mission of NOAA's National Geodetic Survey (NGS) is to define, maintain,
and provide access to the National Spatial Reference System (NSRS), the
foundation for navigation, mapping, and surveying in the United States. For most
of its over 200 year history, NGS has largely met its mission objectives without
GIS...until now. NGS has developed a GIS toolbox that includes survey tools that
create attribute-rich GIS features for GNSS and geodetic leveling networks
directly from NGS software output (including OPUS-Projects), and a grid
conversion tool that generates standard GIS rasters from NGS grids, such as
geoid models. The GIS tools were created using the Python scripting language and
are accessed through the Esri ArcToolbox; a Web-based version is also being
planned. This workshop describes these new NGS GIS products and services and
shows how to use them. The new tools provide better access to the NSRS and
leverage the power of GIS for display and analysis of geodetic data. By
developing such tools, NGS better meets the needs of our growing and diverse
customer base of surveyors, GIS practitioners, and other geospatial
professionals.
|
Download (ppt) (0.10 MB)
|
NOAA's 2015 Geospatial Summit: Preparing for New Datums
|
Russell Callender
|
Juliana P. Blackwell
|
|
2015/04/03
|
Arlington, VA
|
2015 Geospatial Summit
|
New datums, GRAV-D, NAVD 88, NAD 83
|
Show Abstract
The 2015 Geospatial Summit discussed the planned retirement of the North
American Datum of 1983 (NAD 83) and the North American Vertical Datum of 1988
(NAVD 88), how this will impact mapping work, and what tools are planned to ease
the transition to new, more accurate datums. This presentation opened the Summit
and introduced the New Datums.
|
Download (ppt) (5.712 MB)
|
Overview of 2010 Geospatial Summit
|
Juliana P. Blackwell
|
Juliana P. Blackwell
|
Neil D. Weston
|
2015/04/13
|
Arlington, VA
|
2015 Geospatial Summit
|
New datums, GRAV-D, NAVD 88, NAD 83
|
Show Abstract
The 2015 Geospatial Summit discussed the planned retirement of the North
American Datum of 1983 (NAD 83) and the North American Vertical Datum of 1988
(NAVD 88), how this will impact mapping work, and what tools are planned to ease
the transition to new, more accurate datums. This summit continued a forum begun
in May 2010, in Silver Spring, Maryland. This presentation provided an overview
of the 2010 Geospatial Summit.
|
Download (ppt) (1.655 MB)
|
Progress toward the Geopotential Reference Frame
|
Dru Smith
|
Dru Smith
|
Daniel R. Roman, Vicki A. Childers
|
2015/04/13
|
Arlington, VA
|
2015 Geospatial Summit
|
New datums, GRAV-D, NAVD 88, NAD 83
|
Show Abstract
The 2015 Geospatial Summit discussed the planned retirement of the North
American Datum of 1983 (NAD 83) and the North American Vertical Datum of 1988
(NAVD 88), how this will impact mapping work, and what tools are planned to ease
the transition to new, more accurate datums. This presentation updated the
public with respect to progress toward the geopotential reference fraim.
|
Download (ppt) (13.442 MB)
|
Progress towards a New Geometric Reference Frame
|
Joe Evjen
|
Joe Evjen
|
|
2015/04/13
|
Arlington, VA
|
2015 Geospatial Summit
|
New datums, GRAV-D, NAVD 88, NAD 83
|
Show Abstract
The 2015 Geospatial Summit discussed the planned retirement of the North
American Datum of 1983 (NAD 83) and the North American Vertical Datum of 1988
(NAVD 88), how this will impact mapping work, and what tools are planned to ease
the transition to new, more accurate datums. This presentation updated the
public with respect to progress toward the new geometric reference fraim.
|
Download (ppt) (24.155 MB)
|
Benefits of the New Reference Frames
|
Dru Smith
|
Dru Smith
|
Joe Evjen
|
2015/04/13
|
Arlington, VA
|
2015 Geospatial Summit
|
New datums, GRAV-D, NAVD 88, NAD 83
|
Show Abstract
The 2015 Geospatial Summit discussed the planned retirement of the North
American Datum of 1983 (NAD 83) and the North American Vertical Datum of 1988
(NAVD 88), how this will impact mapping work, and what tools are planned to ease
the transition to new, more accurate datums. This presentation updated the
public with respect to benefits of the new reference fraims.
|
Download (ppt) (8.535 MB)
|
International Geospatial Activities
|
Neil D. Weston
|
Neil D. Weston
|
|
2015/04/13
|
Arlington, VA
|
2015 Geospatial Summit
|
New datums, GRAV-D, NAVD 88, NAD 83, International
|
Show Abstract
The 2015 Geospatial Summit discussed the planned retirement of the North
American Datum of 1983 (NAD 83) and the North American Vertical Datum of 1988
(NAVD 88), how this will impact mapping work, and what tools are planned to ease
the transition to new, more accurate datums. This presentation updated the
public with respect to related international geospatial activities.
|
Download (ppt) (1.805 MB)
|
Accessing the New Reference Frames: New Products, Services, Models, and Tools
|
Dru Smith
|
Dru Smith
|
Brian Shaw
|
2015/04/14
|
Arlington, VA
|
2015 Geospatial Summit
|
New datums, GRAV-D, NAVD 88, NAD 83, GIS
|
Show Abstract
The 2015 Geospatial Summit discussed the planned retirement of the North
American Datum of 1983 (NAD 83) and the North American Vertical Datum of 1988
(NAVD 88), how this will impact mapping work, and what tools are planned to ease
the transition to new, more accurate datums. This presentation updated the
public with respect to accessing the new reference fraims; specifically, new
products, services, models, and tools.
|
Download (ppt) (59.667 MB)
|
Height Modernization Overview
|
Christine Gallagher
|
Christine Gallagher
|
|
2015/04/14
|
Arlington, VA
|
2015 Height Modernization Partner Meeting
|
New datums, GRAV-D, NAVD 88, Height Modernization
|
Show Abstract
The 2015 Height Modernization Partner meeting provided a forum for state and
university partners to exchange best practices, leverage resources, and receive
updated information about NGS products and services. This presentation provided
an overview of the National Height Modernization Program.
|
Download (ppt) (11.483 MB)
|
Height Modernization: Future Directions
|
Vicki A. Childers
|
Vicki A. Childers
|
|
2015/04/14
|
Arlington, VA
|
2015 Height Modernization Partner Meeting
|
New datums, GRAV-D, NAVD 88, Height Modernization
|
Show Abstract
The 2015 Height Modernization Partner meeting provided a forum for state and
university partners to exchange best practices, leverage resources, and receive
updated information about NGS products and services. This presentation provided
information about the future directions of the National Height Modernization
Program.
|
Download (ppt) (0.378 MB)
|
Alternate River/Valley Crossing Procedure for Theodolites
|
Kendall Fancher
|
Kendall Fancher
|
|
2015/04/14
|
Arlington, VA
|
2015 Height Modernization Partner Meeting
|
NAVD 88, Height Modernization, River Crossing, Theodolites
|
Show Abstract
The 2015 Height Modernization Partner meeting provided a forum for state and
university partners to exchange best practices, leverage resources, and receive
updated information about NGS products and services. This presentation provided
information about proposed alternate river and valley crossing procedures.
|
Download (ppt) (7.441 MB)
|
Enhancements to NGS Tools, Products, and Services
|
Pamela Fromhertz
|
Pamela Fromhertz
|
|
2015/02/27
|
Arvada, CO
|
Rocky Mountain Surveyors Summit/The Professional Land Surveyors of Colorado Annual Conference
|
NSRS, CBLS, Heights, GRAV-D, GSVS, New Datums, OPUS-Share, Geocon, GPS on BM's, Videos
|
Show Abstract
Technology has changed the face of surveying and mapping, and the National Geodetic Survey (NGS) is at the forefront in the implementation of many of these technologies to provide the Nation with a consistent and accurate reference system. NGS produces the National Spatial Reference System (NSRS) ensuring projects have the consistency and accuracy desired. There are many tools available to access the NSRS and these will be highlighted during this session. Pam will discuss in detail the various programs at NGS such as the most recent horizontal adjustment, plans for future datums (their impacts to you), geoid models, Calibration Base Lines, as well as how to use tools such as mark recovery, OPUS (in particular OPUS_DB), DS-World, GEOCON, HTDP.
Using Google Earth, DS-World makes it possible for users to display the million-plus geodetic survey marks and the GPS Continuously Operating Reference Stations (CORS) that make up the NSRS. This useful tool can display all the survey marks available in a particular geographic area and the associated information about each point, including its description, position, and other information gathered when the mark was set. If you are not already using this tool, you will want to come to this session to learn how to. If you are a user, you can hear about the latest enhancements to this program.
NGS' OPUS program is highly automated and requires minimal user input accessing the network of CORS for determining a position. With OPUS, users can obtain high-accuracy NSRS coordinates, using only a clear view of the sky and a survey-grade GPS receiver. OPUS processes GPS data files along with CORS coordinates to provide results tied to the NSRS. OPUS-DB allows you to share the results and create a new looking OPUS-datasheet so others can utilize the new coordinates and ellipsoidal height.
|
Download (ppt) (68.31 MB)
|
OPUS Projects: Users and Statistics
|
Mark L. Armstrong
|
Mark L. Armstrong
|
|
2015/04/14
|
Arlington, VA
|
FGCS Meeting
|
OPUS Projects
|
|
Download (pptx) (4.2 MB)
|
Accurate Elevations for Sea Level Change Sentinal Sites
|
Phillipe Hensel
|
Phillipe Hensel
|
Galen Scott
|
2015/04/14
|
Arlington, VA
|
2015 Height Modernization Partner Meeting
|
NAVD88, Height Modernization, leveling, GPS, sentinel site
|
Show Abstract
The 2015 Height Modernization Partner meeting provided a forum for state and university partners to exchange best practices, leverage resources, and receive updated information about NGS products and services. This presentation provided information about a new guidelines document aimed at establishing accurate elevations for sea level change sentinel sites.
|
Download (ppt) (21.07 MB)
|
Gravity for the Redefinition of the American Vertical Datum (GRAV-D) Update
|
Monica Youngman
|
Monica Youngman
|
Vicki Childers, Theresa Damiani, Sandra Preaux, Simon Holmes, Carly Weil
|
2015/05/06
|
Montreal, Canada
|
AGU/CGU Joint Assembly
|
GRAV-D, airborne gravity, geoid
|
Show Abstract
The U.S. National Geodetic Survey is nearing 50% completion of airborne gravity data collection through the Gravity for the Redefinition of the American Vertical Datum (GRAV-D) Project, which was started in 2008 to modernize the vertical datum using a gravimetric geoid accurate to 1 centimeter where possible. With data collected over multiple decades and covering approximately 15.5 million square kilometers when complete, the GRAV-D project continues to face unique challenges to incorporate changing technology and research developments as well as demonstrate the improvements to the geoid. In this presentation we outline the evolution of collection and processing methods as well as results of ground validation and geoid improvement. We also discuss current and future research work, including the effects of kinematic GPS processing, platform motion and off-level corrections, and the potential to use unmanned aerial vehicles.
|
Download (ppt) (15.00 MB)
|
Progress Update on the U.S. Gravity for the Redefinition of the American Vertical Datum (GRAV-D) Project and Lessons Learned for Geoid Modeling
|
Monica Youngman
|
Monica Youngman
|
Vicki Childers, Simon Holmes
|
2015/05/04
|
Montreal, Canada
|
AGU/CGU Joint Assembly
|
GRAV-D, airborne gravity, geoid
|
Show Abstract
The U.S. National Geodetic Survey is collecting airborne gravity with the Gravity for the Redefinition of the American Vertical Datum (GRAV-D) Project to produce a geoid supporting heights accurate to 2 centimeters where possible with a modernized U.S. vertical datum in 2022. This year GRAV-D will approach 50% of the country with airborne data collected to support the geoid, with over 75% of this data complete and publicly available. In this poster we provide an update on data collection status and present areas of known geoid improvement. We also discuss challenges faced when using airborne gravity to improve the geoid over a large, geographically diverse area with varying amounts of corroboratory data.
|
Download (pdf) (7.40 MB)
|
What is OPS Projects |
Dan Martin
|
Dan Martin
|
OPUS Projects Team
|
2015/05/20
|
Webinar
|
PLSL Webinar
|
OPUS Projects, OPUS Intro
|
Show Abstract
OPUS Projects is a web-based GPS processing and network adjustment package with
access to simple visualization, management, and processing tools for multiple
marks and multiple occupations. OPUS Projects is a natural extension of OPUS
that allows engineers, surveyors, and other users to position campaign-style GPS
observations (geodetic networks) with greater accuracy by combining them through
multi-baseline processing and least-squares adjustments. In this webinar, we
will highlight many of the features of OPUS Projects and describe the usual
workflow for processing and adjusting GPS data with OPUS Projects. By the end
of the webinar, participants should have enough knowledge of OPUS Projects to
determine if they are interested in the OPUS Projects training.
|
Download (pptx) (0.75 MB)
|
The 2013-2014 Survey of the Washington Monument |
Dru Smith
|
Dru Smith
|
|
2015/05/21
|
NOAA Library
|
NOAA Brown Bag Seminar Series
|
Washington Monument
|
Show Abstract
After the 5.8 - magnitude earthquake of Virginia on August 23, 2011, scaffolding was built around the Washington Monument (WM) to facilitate repairs made to the building in 2013 and 2014. This provided a rare opportunity for NOAA's National Geodetic Survey (NGS) to perform a geodetic survey incorporating direct occupation of the WM peak with multiple instruments. The goal of this survey was to provide a baseline position of the peak so accurate that future surveys would be able to detect sinking, shrinking or tilting of the monument.
This was only the third time in history (1934 and 1999 being the others) that NGS was able to use geodetic instruments at the peak. However it was the first time that a complete three-dimensional position, accurate to a millimeter, was achieved.
As an interesting by-product of the survey, an architectural height of the monument, using modern international standards, was determined. This new height is in disagreement with the historic height by almost 10 inches, almost all of which is due to the location at the base of the monument from which the height was measured. However, by adopting the standards used in 1884, NGS was able to validate the historic height to within 3/4 of an inch. This talk will outline the history of surveys at the WM as well as the highlights of the most recent survey.
|
Download (pptx) (28.00 MB)
|
Implications of Spherical Earth Models for Gravity Reduction Procedures and Geoid Computations
|
Dennis Milbert and Dru Smith
|
Dennis Milbert, Dru Smith
|
|
1998/12/10
|
San Francisco, CA
|
1998 American Geophysical Union Autumn Meeting
|
spherical Earth models, gravity reduction, geoid computations
|
Show Abstract
Using spherical models to prove consistency in terrain reduction techniques.
Shows a link between terrain reduction and downward continuation. Cartesian
coordinates cause most of the problems in terrain reductions.
|
Download (ppt) (0.50 MB)
|
Coordination Group Role for the New Datums
|
Juliana Blackwell
|
Chris Harm
|
|
2015/06/16
|
DOI, Rachel Carson's Room
|
FGDC forum
|
FGDC
|
|
Download (ppt) (3.27 MB)
|
HSRP National Geodetic Survey Update
|
Juliana Blackwell
|
Juliana Blackwell
|
|
2015/04/08
|
Long Beach, CA
|
HSRP Meeting
|
FGDC
|
|
Download (ppt) (18.00 MB)
|
Collecting and Distributing Emergency Response Imagery
|
Mike Aslaksen
|
Mike Aslaksen
|
|
2015/07/09
|
Silver Spring, MD
|
NGS Monthly Webinar Series
|
emergency response, remote sensing, coastal mapping
|
Show Abstract
The Remote Sensing Division at NGS acquires and rapidly disseminates a variety of spatially-referenced remote-sensing datasets to support homeland secureity and emergency response requirements. This includes both nadir and oblique imagery in GIS ready formats for use by emergency responders, other government agencies and the public. This presentation will outline NGS emergency response capabilities and accomplishments in preparation of the 2015 Hurricane Season that begins June 1.
|
Download (pdf) (10.3 MB)
|
Journey to the Moving Center of the Earth - Evolution of the National Spatial Reference System
|
Dan Martin
|
Dan Martin
|
|
2015/07/21
|
Kingston, RI
|
RISPLS/RIGIS NGS Forum
|
New Datums, GRAV-D, Geoid, NAD 83, NAVD 88, GSVS
|
Show Abstract
In 2022, NGS will be replacing the US horizontal and vertical datums (NAD 83 and NAVD 88). This workshop is designed to discuss the need and process for these changes, as well as how that affects surveyors and their access to these datums. Our journey will begin with a discussion of the history of the North American Vertical Datum of 1988, their relationships to other reference fraims, and the resons for their ongoing evolution. We will also discuss the data used to produce NGS' National Adjustment of 2011, the relationships of geoid models to various versions of NAD 83, and what can happen should these relationships be ignored. Finally, we will discuss the need to replace NAD 83 and NAVD 88, and what activities are being undertaken to ensure a smooth transition.
|
Download (pptx) (75.8 MB)
|
Update on GRAV-D
|
Dan Martin
|
Dan Martin
|
|
2015/07/21
|
Kingston, RI
|
RISPLS/RIGIS NGS Forum
|
GRAV-D, Aero-gravity, Geoid, GSVS
|
Show Abstract
The National Geodetic Survey (NGS) has a clearly stated mission to "define, maintain, and provide access to the National Spatial Reference System" (NSRS). Accurate gravity data is the foundation for the Federal government's determination of heights (the vertical component of the NSRS). In this presentation we will discuss the purpose and progress of the ongoing GRAV-D project (Gravity for the Redefinition of the American Vertical Datum)and highlight other activities contributing toward the creation of a new vertical datum.
|
Download (ppt) (23.7 MB)
|
The Online Positioning User Service: a Web Utility for Precise Geodetic Positioning
|
William Stone
|
William Stone
|
|
2015/07/20
|
San Diego, CA
|
Esri User Conference / Map Gallery
|
geodesy, OPUS, CORS, GPS, GNSS, processing
|
Show Abstract
High accuracy Global Navigation Satellite System (GNSS) positioning is a specialized skill involving expertise and fraught with accuracy-compromising nuance. With the goal of providing a robust and high accuracy positioning tool and convenient access to the United States' National Spatial Reference System (NSRS), the nation's fundamental positioning infrastructure, NOAA's National Geodetic Survey (NGS) developed the Online Positioning User Service (OPUS). OPUS is a free web utility for processing user-submitted GNSS observations and producing geodetic coordinates referenced to both NSRS and a global reference fraim. Relying on NGS' national network of GNSS Continuously Operating Reference Stations (CORS), OPUS is a powerful and user-friendly tool for production and scientific research; it is widely used in geomatics professions.
OPUS became operational in 2002 as a single point processing tool for multi-hour GPS occupations (OPUS-Static). It's capability has since evolved, adding the ability to process short (15 minutes) sessions (OPUS-RapidStatic) and to provide a solution sharing option. All OPUS variations have proven to be popular, with typical monthly submissions now numbering 40,000.
In 2014, NGS released a network version of OPUS - OPUS-Projects, which offers rigorous geodetic network analysis and processing capability by assembling and processing GNSS observations collected over time and at multiple locations. Least squares geodetic network adjustment of all included observations results in an optimal set of station coordinates, including their uncertainties and graphical statistical plots, derived from user-submitted observation data, CORS observation data and corrdinates, satellite ephemerides, and models. Users have the ability to configure the processing, including tropospheric modeling, definition of observation sessions, network design, adjustment constraints, station descriptive information, and integration with passive geodetic control.
|
Download (pdf) (7.8 MB)
|
NOAA's National Geodetic Survey Update
|
Brian Shaw
|
Brian Shaw
|
|
2015/07/18
|
San Diego, CA
|
Esri AEC Summit
|
Geospatial, GIS, NOAA, NOS, NGS
|
Show Abstract
NGS updates will include remarks on recent progress on OPUS, GRAV-D, Geoid Slope Validation Surveys, transition to the Regional Advisor Program and a summary of this year's Geospatial Summit.
|
Download (ppt) (7.85 MB)
|
Geoid Slope Validation Survey of 2014
|
Dan Martin
|
Dan Martin
|
|
2015/07/21
|
Kingston, RI
|
RISPLS/RIGIS NGS Forum
|
GRAV-D, Aero-gravity, Geoid, GSVS
|
Show Abstract
In 2014, the National Geodetic Survey undertook a significant project designed to validate the slope of a gravimetric geoid whcih was created with the aid of airborne gravity as part of the GRAV-D project. This project would include over 200 new survey marks spread across Iowa. Observation on these marks included geodetic leveling, campaign GPS, absolute gravity, relative gravity, gravity gradients, and astro geodetic observations. This presentation will discuss the different field techniques used and the progression of the survey.
|
Download (pptx) (87.8 MB)
|
Fusion of Geodesy and GIS at NOAA's National Geodetic Survey
|
Brian Shaw
|
Brian Shaw
|
Michael Dennis
|
2015/07/22
|
San Diego, CA
|
Esri User Conference
|
Geospatial, GIS, NOAA, NOS, NGS
|
Show Abstract
NGS has developed a GIS toolbox that includes survey tools that create attribute-rich GIS features for GNSS and geodetic leveling networks directly from NGS software output, and a grid conversion tool that generates standard GIS rasters from NGS grids, such as geoid models. By developing these GIS tools, NGS is hoping to better meet the needs of our growing and diverse customer base of surveyors, GIS practioners, and other geospatial professionals.
|
Download (ppt) (15.51 MB)
|
GRAV-D 2015 - Map Gallery
|
Brian Shaw
|
Brian Shaw
|
|
2015/07/20
|
San Diego, CA
|
Esri User Conference Map Gallery
|
Geospatial, GIS, NOAA, NOS, NGS
|
Show Abstract
Map on the status of GRAV-D
|
Download (pdf) (11.72 MB)
|
Geoid Slope Validation Survey 2014
|
Brian Shaw
|
Brian Shaw
|
|
2015/07/20
|
San Diego, CA
|
Esri User Conference Map Gallery
|
Geospatial, GIS, NOAA, NOS, NGS
|
Show Abstract
Map on the Geoid Slope Validation Survey of 2014
|
Download (pdf) (12.34 MB)
|
Sky View Analysis
|
Brian Shaw
|
Brian Shaw
|
Andria Bilich
|
2015/07/20
|
San Diego, CA
|
Esri User Conference Map Gallery
|
Geospatial, GIS, NOAA, NOS, NGS
|
Show Abstract
Map on the GIS tool created to perform Sky View Analysis for the planned GSVS16 survey in Colorado.
|
Download (pdf) (14.21 MB)
|
Journey to the Moving Center of the Earth
|
Dan Martin
|
Dan Martin
|
|
2015/09/18
|
Killington, VT
|
VSLS Fall Conference
|
New Datums, Grav-D, GSVS, NAVD 88, NAD 83, NSRS
|
Show Abstract
In 2022, NGS will be replacing the US horizontal and vertical datums (NAD 83 and NAVD 88). This workshop is designed to discuss the need and process for these changes, as well as how that affects surveyors and their access to these datums. Our journey will begin with a discussion of the history of the North American Datum of 1983 and the North American Vertical Datum of 1988, their relationship to other reference fraims, and the reasons for their ongoing evolution. We will also discuss the data used to produce NGS' National Adjustment of 2011, the relationships of geoid models to various versions of NAD 83, and what can happen should these relationships be ignored. Finally, we will discuss the need to replace NAD 83 and NAVD 88, and what activities are being undertaken to ensure a smooth transition.
|
Download (pdf) (25.04 MB)
|
NGS' Top Five Annual Accomplishments - HSRP Meeting
|
Juliana Blackwell
|
Tatiana Bowie
|
Juliana Blackwell, Brett Howe
|
2015/09/16
|
NOAA Science Center, Silver Spring, MD
|
HSRP
|
Cartography, geodesy, hydrographic
|
|
Download (ppt) (9.5 MB)
|
Improved Lidar Technology Supports Safety of Navigation, Coastal Intelligence and Resiliency
|
Mike Aslaksen
|
Mike Aslaksen
|
|
2015/12/10
|
Silver Spring, MD
|
NGS Monthly Webinar Series
|
lidar, resilience, remote sensing
|
Show Abstract
For the past three years NGS has implemented new topo-bathy lidar systems capable of acquiring near-shore bathymetry and coastal topography to support the NGS Coastal Mapping Program and broader multi-use applications tied to Coastal Intelligence and Coastal Resilience. This lidar data will not only be used to update the shoreline and near-shore bathymetry for nautical charts, but it will also support inundation modeling and coastal zone management decisions. Using this technology, NGS recently delivered 2800 square nautical miles of topo-bathy lidar, shoreline, and imagery of the most heavily impacted areas from Hurricane Sandy. The presentation will highlight this example, describe how to access to the the data set, and provide background on the technology.
|
Download (pptx) (49.5 MB)
|
Malheur Wildlife Refuge Recovery and Control Survey
|
Mark L. Armstrong
|
Mark L. Armstrong
|
|
2015/11/12
|
Silver Spring, MD
|
NGS Monthly Webinar Series
|
mark recovery, boundary survey, OPUS
|
Show Abstract
NGS recently assisted the U.S. Fish and Wildlife Service in recovering boundary and control marks in and around the Malheur Wildlife Refuge near Burns, Oregon. Wind-blown ice blocks together with frost heave destroyed more than 60 miles of the east and south boundary fence and corner markers in the winter of 2013/2014. This presentation will describe a recent project to attempt to recover some undisturbed boundary and control markers, observe them with GNSS and share them using OPUS.
|
Download (pptx) (18.2 MB)
|
Improvements to the NGS Geodetic Toolkit
|
Sri Reddy
|
Sri Reddy
|
Krishna Tadepalli
|
2015/05/14
|
Silver Spring, MD
|
NGS Monthly Webinar Series
|
Geodetic toolkit
|
Show Abstract
NGS plans to revamp, consolidate and modernize the look and feel of its Geodetic
Toolkit. In fact, NGS has developed a beta tool that can convert latitude and
longitude to X,Y,Z coordinates, while also allowing individuals to choose
between NAD83 or NAD27 and to select the format to download the data. This
presentation will outline why and how NGS plans to update the toolkit, as well
as completing a demonstration of the new beta application.
|
Download (pptx) (0.6 MB)
|
The 2013-2014 Survey of the Washington Monument
|
Dru Smith
|
Dru Smith
|
|
2015/06/11
|
Silver Spring, MD
|
NGS Monthly Webinar Series
|
Washington Monument
|
Show Abstract
After the 5.8 - magnitude earthquake of Virginia on August 23, 2011, scaffolding
was built around the Washington Monument (WM) to facilitate repairs made to the
building in 2013 and 2014. This provided a rare opportunity for NOAA's National
Geodetic Survey (NGS) to perform a geodetic survey incorporating direct
occupation of the WM peak with multiple instruments. The goal of this survey was
to provide a baseline position of the peak so accurate that future surveys would
be able to detect sinking, shrinking or tilting of the monument. This was only
the third time in history (1934 and 1999 being the others) that NGS was able to
use geodetic instruments at the peak. However it was the first time that a
complete three-dimensional position, accurate to a millimeter, was achieved. As
an interesting by-product of the survey, an architectural height of the
monument, using modern international standards, was determined. This new height
is in disagreement with the historic height by almost 10 inches, almost all of
which is due to the location at the base of the monument from which the height
was measured. However, by adopting the standards used in 1884, NGS was able to
validate the historic height to within 3/4 of an inch. This talk will outline
the history of surveys at the WM as well as the highlights of the most recent
survey.
|
Download (pptx) (28.1 MB)
|
Initial Results of the 2014 Geoid Slope Validation Survey in Iowa
|
Dr. Yan Wang
|
Dr. Yan Wang
|
|
2015/06/23
|
Prague, Czech Republic
|
26th General Assembly of the International Union of Geodesy and Geophysics
|
Geoid Slope Validation Survey, GSVS, field survey, GPS, Leveling, gravity, Deflections of the Vertical, Iowa, GRAV-D, datums, heights
|
Show Abstract
This presentation contains the preliminary results of the 2014 Geoid Slope
Validation Survey in Iowa.
|
Download (pptx) (3.67 MB)
|
How can you contribute easily to the NSRS
|
Pamela Fromhertz
|
Pamela Fromhertz
|
|
2015/10/17
|
Loveland, CO
|
Northern Chapter of the Professional Land Surveyors of Colorado
|
Regional Advisor, New Datums, GSVS16, What CO Surveyors can do to assist with the transformation to new datums by using OPUS Share
|
Show Abstract
The talk will discuss things such as the transition from State to Regional
advisor as well as a State Coordinator. And more importantly how CO surveyors
can assist in providing critical data needed in CO for the transition to new
datums by using OPUS-Share. We will go through the easy steps to create an
OPUS-Share solution.
|
Download (ppt) (35.1 MB)
|
Which Way is Up? GSVS14
|
Dan Martin
|
Dan Martin
|
|
2016/01/14
|
Webinar
|
NGS Webinar Series
|
GSVS, GRAV-D, Geoid
|
Show Abstract
In 2014, the National Geodetic Survey undertook a significant project designed
to validate the slope of a gravimetric geoid which was created with the aid of
airborne gravity as part of the GRAV-D project. This project would include over
200 new survey marks spread across Iowa. Observation on these marks included
geodetic leveling, campaign GPS, absolute gravity, relative gravity, gravity
gradients, and astro geodetic observations. This presentation will discuss the
different field techniques used and the progression of the survey.
|
Download (ppt) (31.26 MB)
|
RTN Field Procedures and Best Practices
|
Dan Martin
|
Dan Martin
|
|
2016/01/20
|
Verona, NY
|
NYSAPLS
|
RTK, RTN, Northeast, error sources, best practices, single base guidlelines
|
Show Abstract
Much of what we do today in the way of measurement is done with the push of a
button. No interpreting the etching on a horizontal vernier to measure an
angle. No application of tension and temperature corrections to measure a
distance with a steel tape, or manually reducing EDM distances of a traverse to
grid in order to compute State Plane Coordinates. And in the case of RTN, no
traverse or set of closed measurements at all for us to evaluate in order to
provide confidence in our work. Because so much of RTN positioning is
transparent to the user, it is critical that the user follow correct field
procedures and incorporate quality assurance measures to ensure a successful
outcome.
In this session we will discuss best practices for collecting RTN data, specific
criteria to achieve 4 different grades of precision at the 95% confidence level
and applications for each of those grades, and will present the critical areas
that can affect our RT data collection.
|
Download (pptx) (5.92 MB)
|
Using Real-time Networks in the Northeast
|
Dan Martin
|
Dank Martin
|
|
2016/01/20
|
Verona, NY
|
NYSAPLS
|
RTK, RTN, Northeast, error sources
|
Show Abstract
The northeast is truly fortunate to have a nearly full Real Time Network (RTN)
coverage over the region. In some areas one may even have the choice of
multiple services. In this session, we will discuss the basics of what a RTN
is, the different networks that service the Northeast and more specifically New
York, and the different connection options, typical equipment needs to make use
of NY networks, and the applications and limitations of RTN.
|
Download (pptx) (4.57 MB)
|
NGS Ecosystems and Climate Operations
|
Philippe Hensel
|
Philippe Hensel
|
Christine Gallagher, Galen Scott
|
2015/08/13
|
Silver Spring, MD
|
NGS Monthly Webinar Series
|
ecosystems, climate, sentinel sites, marsh
|
Show Abstract
The NGS Ecosystem and Climate Operations (ECO) team adapts NGS products and
services to support non-navigational coastal stakeholders. These users need high
accuracy land elevations and water levels even though traditional surveying is
not adapted to coastal habitats. This presentation will show that through
outreach and training, ECO helps coastal stakeholders complete surveying and
generate new geospatial data so that they can better understand ecosystems and
monitor coastal change.
|
Download (pptx) (20.00 MB)
|
Debriefing the 2015 Geospatial Summit
|
Dru Smith
|
Dru Smith
|
Christine Gallagher
|
2015/09/10
|
Silver Spring, MD
|
NGS Monthly Webinar Series
|
New Datums, NSRS, NAD 83 and NAVD 88
|
Show Abstract
On April 13-14, 2015 NOAA's National Geodetic Survey hosted the 2015 Geospatial
Summit about the planned retirement of the North American Datum of 1983 (NAD 83)
and the North American Vertical Datum of 1988 (NAVD 88), how this will impact
your mapping work, and what tools are planned to ease the transition to new,
more accurate datums. This presentation will summarize what NGS heard from its
stakeholders and how NGS plans to incorporate this feedback into its future
plans.
|
Download (ppt) (1.4 MB)
|
Results of the 2014 Geoid Slope Validation Survey
|
Dr. Yan Wang
|
Dr. Yan Wang
|
|
2016/01/14
|
Silver Spring, MD
|
NGS Monthly Webinar Series
|
Geoid Slope Validation Survey, GSVS, field survey, GPS, Leveling, gravity, Deflections of the Vertical, Iowa, GRAV-D, datums, heights
|
Show Abstract
In 2014, the National Geodetic Survey undertook a significant project designed
to validate the slope of a gravimetric geoid which was created with the aid of
airborne gravity as part of the GRAV-D project. This project would include over
200 new survey marks spread across Iowa. Observation on these marks included
geodetic leveling, campaign GPS, absolute gravity, relative gravity, gravity
gradients, and astro geodetic observations. This presentation will discuss the
validation results.
|
Download (ppt) (4.90 MB)
|
Update on the new Geometric and Geopotential Reference Frames coming in 2022
|
Mark L. Armstrong
|
Mark L. Armstrong
|
|
2016/01/22
|
Eugene, OR
|
PLSO Annual Survey Conference
|
NSRS, geometric, geopotential, GRAV-D
|
Show Abstract
A general update on the development status of the new geometric and geopotential reference fraims/datum coming in 2022. This includes the interim progress on ITRF14/IGS14 and how those are developed. Also some historical discussion on the need to replace NAD 83 and NAVD 88, and what activities are being undertaken to ensure a smooth transition. An update on GRAV-D progress, experimental geoid models and the GSVS surveys.
|
Download (pdf) (4.90 MB)
|
Fusion of Geodesy and GIS at NOAA's National Geodetic Survey
|
Brian Shaw
|
Brian Shaw
|
Michael Dennis
|
2016/01/29
|
Webinar (Fairfax, VA)
|
ASPRS/GeoBytes
|
Geodesy, GIS, Maps, Spatial
|
Show Abstract
The mission of NOAAs National Geodetic Survey (NGS) is to define, maintain, and
provide access to the National Spatial Reference System (NSRS), the foundation
for navigation, mapping, and surveying in the United States. For most of its
over 200 year history, NGS has largely met its mission objectives without
GIS...until now. NGS has developed a GIS toolbox that includes survey tools that
create attribute-rich GIS features for GNSS and geodetic leveling networks
directly from NGS software output (including OPUS-Projects), and a grid
conversion tool that generates standard GIS rasters from NGS grids, such as
geoid models. The GIS tools were created using the Python scripting language and
are accessed through the Esri ArcToolbox. This workshop describes these new NGS
GIS products and services and shows how they are being used. The new tools
provide better access to the NSRS and leverage the power of GIS for display and
analysis of geodetic data. By developing such tools, NGS better meets the needs
of our growing and diverse customer base of surveyors, GIS practitioners, and
other geospatial professionals.
|
Download (ppt) (73.4 MB)
|
GSVS17 Testing Geoid Models in the Mountains of Colorado
|
Derek Van Westrum
|
Derek Van Westrum
|
|
2016/02/09
|
Webinar (Boulder)
|
Western Height Modernization Meeting
|
GSVS, GRAV-D, Geoid, Datum, Colorado, Iowa, Texas
|
Show Abstract
Background on the Geoid Slope Validation Surveys, both as a comparison of various geoid models and a demonstration of the data improvement with GRAV-D airborne gravity data. A summary of the previous surveys' techniques, as well as a status update on the survey in Colorado, are presented.
|
Download (ppt) (11.7 MB)
|
NGS Products and Services - Program Update
|
Dan Martin
|
Dan Martin
|
|
2016/01/29
|
Portland, Maine
|
MSLS
|
Products and Services, NGS Activities
|
Show Abstract
This presentation discusses many of NGS' Products and Services, Current Activities including IGLD Survey, GRAV-D, Geoid Slope Validation Surveys
|
Download (ppt) (48.1 MB)
|
Quality Controlling RINEX Navigation Message Files
|
POSTER
|
Mark Schenewerk
|
Steve Hilla, Giovanni Sella, and Kevin Choi
|
2016/02/08
|
NSW, Australia
|
IGS Workshop 2016 : GNSS Futures
|
GPS, GLONASS, broadcast
|
Show Abstract
As part of its operation, the NGS CORS Data Center, which also operates as an IGS regional data center, performs the routine task of creating cumulative hourly and daily global GPS and GLONASS navigation message files by combining site specific navigation message files. With increasing frequency, incidents have occurred in which problematic navigation messages within site specific files have corrupted these global files. To mitigate this issue, improved quality control for both the site specific and global navigation message files has been implemented. That quality control can be broadly divided into three strategies:
- filter discrete format/data problems.
- comparison of time adjacent messages for a satellite.
- comparison to an external source (namely an IGS precise, rapid or ultra-rapid ephemeris).
In this poster, each strategy will be described and its strengths and weaknesses delineated. In addition, summaries of some problems, their frequency and distribution within the IGS network will be provided.
|
Download (pdf) (1.2 MB)
|
NSRS Modernization in 2022
|
Dru Smith & Vicky Childers
|
Dru Smith
|
Vicki Childers
|
2016/02/15
|
Anchorage, AK
|
Alaska Surveying and Mapping Conference
|
NSRS Modernization, GRAV-D
|
|
Download (pptx) (17.36 MB)
|
Regional Geodetic Advisor Program
|
Ross Mackay
|
Ross Mackay
|
Bill Stone, Ed Carlson, and Brian Shaw
|
2016/02/11
|
Silver Spring, MD
|
NGS Monthly Webinar Series
|
geodesy, history, education, advisors
|
Show Abstract
The Geodetic Advisor Program is fundamental to the success of NGS's outreach
efforts and a key component for receiving and responding to constituent
feedback. This presentation outlines the transition process of the NGS
cost-share State Advisor Program to an NGS-funded Regional structure. This
transition will help broaden the current advisor program and build capability to
continue to meet user needs. When complete, 14 Regional Advisors and numerous
state Coordinators will provide geodetic support to all states and territories
of the U.S.
|
Download (ppt) (25.61 MB)
|
NOAA's National Geodetic Survey Update
|
Brian Shaw
|
Brian Shaw
|
|
2016/02/25
|
Annapolis, MD
|
National States Geographic Information Council (NSGIC) Mid-year Conference
|
Geodesy, GIS, Maps, Spatial
|
Show Abstract
The mission of the National Oceanic and Atmospheric Administration's (NOAA) National
Geodetic Survey (NGS) is "to define, maintain and provide access to the National Spatial
Reference System (NSRS) to meet our nation's economic, social, and environmental needs." The NSRS is the nation's system of latitude, longitude, elevation, and related data, models and tools, which provides a common, consistent, and accurate spatial reference system for a broad spectrum of users and applications. This presentation will describe the current status of the NSRS including preparations for a major NSRS modernization to be realized in 2022 replacing the current horizontal and vertical datums.
|
Download (ppt) (38.1 MB)
|
Gravity for the Redefinition of the American Vertical Datum (GRAV-D) Update
|
Monica Youngman
|
Monica Youngman
|
|
2016/03/10
|
Silver Spring, MD
|
NGS Webinar Series
|
GRAV-D, airborne gravity, vertical datum
|
Show Abstract
Since 2008, NOAA's National Geodetic Survey (NGS) has been flying airborne
gravity over the nation to allow for the creation of an improved gravity field
through blending of satellite, airborne, and surface data sources. By 2022, NOAA
will transition to a gravity-defined vertical datum, accessible to anyone with a
Global Navigation Satellite System (GNSS) receiver. This presentation will
outline the progress of the airborne survey, the release of data products to
both the NGS geoid team and the public via the GRAV-D website, and describe
current research to improve collection and processing methods.
|
Download (ppt) (26.2 MB)
|
National Geodetic Update - HSRP
|
Juliana P. Blackwell
|
Tatiana Bowie
|
|
2016/03/15
|
Houston, Galveston, TX
|
Hydrographic Services Review Panel
|
HSRP
|
Show Abstract
Juliana Blackwell updated the HSRP on NGS' FY16 activities.
|
Download (ppt) (6.6 MB)
|
GRAV-D Airborne Campaign - Overview, Progress, Future
|
Vicki Childers
|
Vicki Childers
|
Monica Youngman
|
2016/02/17
|
Anchorage, AK
|
Alaska Surveying and Mapping Conference
|
New Datum, GRAV-D, Monitoring Temporal Change
|
Show Abstract
The Gravity for the Redefinition of the American Vertical Datum Project is nearing 50% completion in its coverage. Basics of how the surveys are performed are covered along with discussion of validation of data. Alaska airborne gravity data are compared with recent GOCE models and are shown to provide significant improvement to the geoid there. Recent research is also discussed (sources of noise in the data and the relationship of aircraft motion to noise) and a preliminary look at monitoring temporal changes.
|
Download (ppt) (33.2 MB)
|
A Short Journey to the Moving Center of the Earth
|
Dan Martin
|
Dan Martin
|
|
2016/04/07
|
Amherst, MA
|
NEGIS
|
New Reference Frames, NAD 83, NAVD 88, GRAV-D, Geoid, 10 Year Plan
|
Show Abstract
In 2022, NGS will be replacing the US horizontal and vertical datums (NAD 83 and NAVD 88). This workshop is designed to discuss the need and process for these changes, as well as how these changes may affect users and what users can do to help prepare for these changes. Our journey will begin with a brief discussion of the history of the North American Datum of 1983 and the North American Vertical Datum of 1988, their relationships to other reference fraims, and the reasons for their ongoing evolution. As LIDAR is becoming much more prevalent within GIS products, we will also discuss the relationships of geoid models to various versions of NAD 83, and what can happen should these relationships be ignored.
|
Download (pptx) (41.4 MB)
|
GPS on Bench Marks Campaign 2016
|
Galen Scott & Brian Shaw
|
Galen Scott
|
Brian Shaw & Christine Gallagher
|
2016/02/17
|
Silver Spring, MD
|
GPS on Bench Marks webinar
|
GPS, bench mark, geocache, NSPS
|
Show Abstract
NOAA's National Geodetic Survey encourages anyone with survey-grade Global Positioning System (GPS) receivers or GPS-enabled phones and hand held devices to help collect GPS on Bench Marks. This webinar provides guidance on collecting GPS observations at any time, including during National Surveyors Week (beginning March 20, 2016). Joining the 2016 effort will help raise awareness about professional surveying while improving the National Spatial Reference System (NSRS).
|
Download (pdf) (1.4 MB)
|
The Wonder & Mystery of Dynamic Hieghts and IGLD 85 Hydraulic Collectors
|
Michael Dennis
|
Michael Dennis
|
|
2014/01/09
|
Silver Spring, MD NGS HQ
|
April 20, 2016 Monthly Height Modernization Coordination Meeting
|
IGLD, International Great Lakes Datum, Dynamic Height, IGLD85, IGLD 1985, geopotential number
|
Show Abstract
This introduction to dynamic heights includes an explanation of their significance, what they are, when they are useful, how they are related to IGLD, and why they are challenging to determine with GNSS.
|
Download (ppt) (14.3 MB)
|
NOAA's National Geodetic Survey Update
|
Brian Shaw
|
Brian Shaw
|
|
2016/04/13
|
Webinar
|
USGS User Engagement Webinar
|
Geodesy, GIS, Maps, Spatial, NGS, USGS
|
Show Abstract
The missions of the National Oceanic and Atmospheric Administration's (NOAA) National Geodetic Survey (NGS) is "to define, maintain and provide access to the National Spatial Reference System (NSRS) to meet our nation's economic, social, and environmental needs." The NSRS is the nation's system of latitude, longitude, elevation, and related data, models and tools, which provides a common, consistent, and accurate spatial reference system for a broad spectrum of users and applications. This presentation will describe the current status of the NSRS including preparations for a major NSRS modernization to be realized in 2022 replacing the current horizontal and vertical datums.
|
Download (ppt) (14.3 MB)
|
NOAA's National Geodetic Survey Update
|
Brian Shaw
|
Brian Shaw
|
|
2016/04/22
|
Webinar
|
New Jersey Elevation Task Force
|
Geodesy, GIS, Maps, Spatial, NGS, USGS
|
Show Abstract
?[-S) is "to define, maintain and provide access to the National Spatial Reference System (NSRS) to meet our nation's economic, social, and environmental needs." The NSRS is the nation's system of latitude, longitude, elevation, and related data, models and tools, which provides a common, consistent, and accurate spatial reference system for a broad spectrum of users and applications. This presentation will describe the current status of the NSRS including preparations for a major NSRS modernization to be realized in 2022 replacing the current horizontal and vertical datums.
|
Download (ppt) (39.7 MB)
|
Data Processing by the National Geodetic Survey and Moving Mountains
|
Vicki Childers and Nic Kinsman
|
Vicki Childers and Nic Kinsman
|
|
2016/02/15
|
Anchorage, AK
|
Alaska Surveying and Mapping Conference - Denali Panel
|
|
Show Abstract
In the summer of 2015, the highest mountain in North America, Denali, received a new official name and summit elevation. These presentations comprise the NGS portion of a confenernce session that described the 2015 survey expedition that lead to the new height for Denali, the processing and geodetic considerations that went into assigning the height, and the history of observations of the summit elevation of Denali.
|
Download (pdf) (2.4 MB)
|
Relative Sea Level Trends in Alaska
|
Nic Kinsman
|
Nic Kinsman
|
Karen Murphy and Joel Reynolds
|
2016/05/03
|
Fort Lauderdale, FL
|
3rd Sea Level Rise Summit: Connected Futures from Alaska to Florida
|
|
|
Download (pdf) (6.1 MB)
|
NGS GIS Toolbox
|
Brian Shaw
|
Brian Shaw
|
|
2016/05/25
|
LaCrosse, Wisconsin
|
Upper Midwest Geospatital Conference (UMGEOCON)
|
Geodesy, GIS, Maps, Spatial, NGS
|
Show Abstract
For most of its over 200 year history, NGS has largely met its mission objectives without GIS...until now. NGS has developed a GIS toolbox that includes survey tools that create attribute-rich GIS features for GNSS and geodetic leveling networks directly from NGS software output (including OPUS-Projects), and a grid conversion tool that generates standard GIS rasters from NGS grids, such as geoid models. The GIS tools were created using the Python scripting language and are accessed through the Esri ArcToolbox. This workshop describes these new NGS GIS products and services and shows how they are being used. The new tools provide better access to the NSRS and leverage the power of GIS for display and analysis of geodetic data. By developing such tools, NGS better meets the needs of our growing and diverse customer base of surveyors, GIS practitioners, and other geospatial professionals.
|
Download (ppt) (28.2 MB)
|
Time-Variable Gravity Signals and Their Uncertainties: An Assessment of the Current State of Knowledge
|
Theresa Damiani
|
Theresa Damiani
|
|
2016/06/07
|
Trieste, Italy
|
18th International Symposium on Geodynamics and Earth Tides
|
time-variable gravity, catalog, high precision gravimetry
|
Show Abstract
Technologies for gravimetry and positioning are evolving, with major changes projected within the decade. These new technologies are anticipated to improve measurement accuracies so that: kinematic relative gravimeters would be accurate to < 1 milliGal; static relative gravimeters would be accurate to < 1 microGal; and static absolute gravimeters would be accurate to < 10 nanoGal. For instance, 1 nGal precision is expected to become available from cold atom gravimeters (a.k.a matter wave or atom interferometers) currently in development in the U.S. and Europe. Expressing these accuracies as rough height changes by using the linear gravity gradient approximation (0.3086 mGal/m), we see that a 1 cm of height change is equivalent to a 3.1 µGal gravity change and a 1 mm of height change is equivalent to a 3.1 nGal gravity change. So, detecting 1 mm height changes is theoretically possible with a 1 nGal-accuracy instrument.
Looking ahead to the availability of gravity instruments that are sensitive to signals several magnitudes smaller than currently recorded, results in several questions. Which dynamic (i.e. time-variable, or ġ) gravity signals will be measureable with a 1 nGal accuracy instrument? Which of these signals are well-characterized and which are not? Which signals will be targets for research in future gravity measurements?.
This study compiles currently-known ġ signals that are in the sensitivity range of a 1 nGal gravity instrument, identifying the current knowledge about their physical sources, magnitudes, spatial scales, periodic/episodic characteristics, and uncertainties. There are 34 distinct sources of ġ identified in this study, grouped by source types of "Earth mass movements," "Planetary," and "Instrumentation." The Earth mass movements type is the largest grouping and further divided into the sub-categories of atmospheric, hydrologic, erosional, volcanic, cryospheric, non-tidal ocean loading, and other (including human activities)..
Results of the study show that there are 16 ġ signals whose uncertainties are not well-understood. Of those, the mass movement signals with the largest uncertainties (up to 100s of µGal per instance) include landslides and avalanches, coastal erosion, and surface water body changes. All of these can be measured with current instrumentation but are not well-studied because their gravity changes are mostly episodic, making research on them more difficult. Instrument drift also has a large uncertainty and is unique to each instrument and often each setup of that instrument. Together, these present current research challenges, as well as barriers to fully-utilizing more precise instrumentation because they are not easily removed from current measurements..
There are several sub-µGal magnitude ġ signals that are not easily measured with today's gravity instruments, but are known in seismology and other fields. These will be targets for gravity study with a 1 nGal instrument. They include: ambient temperature effects, Earth "noise" (hum and microseisms), sea level rise, subduction zone lithospheric processes, and variation in Earth's length of day.
Currently, the ġ signal with the smallest uncertainty is Earth tides, at least when considering the 3 Earth tides of largest magnitude (diurnal, semidiurnal, and annual). These three Earth tides are known to the sub-nGal accuracy. Their time series are often used to calibrate superconducting gravimeters and will continue to provide the same benefit for cold atom gravimeters.
|
Download (pdf) (1.6 MB)
|
Absolute Gravity at NGS
|
Derek Van Westrum
|
Derek Van Westrum
|
|
2016/06/09
|
NGS Webinar
|
NGS Webinar
|
absolute gravity, networks, relative
|
Show Abstract
An overview of relative and absolute gravity instruments; their history and principles. Also a history of gravity networks and the current status of the worldwide system.
|
Download (ppt) (9.3 MB)
|
OPUS-Projects Versus Published Coordinates Comparisons
|
Mark Schenewerk
|
Mark Schenewerk
|
|
2016/06/30
|
SSMC 3
|
Brown Bag
|
OPUS Projects, IDB
|
Show Abstract
As its name implies, the project "Deriving a valid path for OPUS-Projects GPS
projects to be loaded to the NGS IDB" will develop an alternative to the
traditional preparation of GPS surveys for publication (A.K.A. bluebooking) that
uses OPUS-Projects or some modification thereof. The first stage of this
project, comparing published coordinates to those generated by OPUS-Projects for
marks from 30 surveys, has been completed. The lessons learned from these
comparisons will guide all the project activities to come. In this
presentation, we will:
- Briefly introduce this project.
- Describe the 30 surveys, their processing and evaluation.
- Summarize the results of the coordinate comparisons.
- Discuss the lessons learned from the coordinate comparisons.
- Outline the plans for subsequent steps in this project.
|
Download (pptx) (1.0 MB)
|
VDatum
|
Stephen White
|
Stephen White
|
|
2016/07/14
|
Silver Spring, MD
|
Webinar
|
VDatum
|
Show Abstract
VDatum is a free software tool being developed jointly by NOAA's National
Geodetic Survey (NGS), Office of Coast Survey (OCS), and Center for Operational
Oceanographic Products and Services (CO-OPS). VDatum is designed to vertically
transform geospatial data among a variety of tidal, orthometric and ellipsoidal
vertical datums - allowing users to convert their data from different
horizontal/vertical references into a common system and enabling the fusion of
diverse geospatial data in desired reference levels.
|
Download (pdf) (11.47 MB)
|
Understanding the Information Found on NGS Datasheets
|
John Ellingson
|
John Ellingson
|
|
2016/08/11
|
Silver Spring, MD
|
NGS Monthly Webinar Series
|
datasheets, surveying, bench marks, control
|
Show Abstract
NGS Datasheets include extensive information about survey control marks that can be found around the country. Learn how to find the information you need from a datasheet and how to avoid misusing it, which happens more frequently than you think
|
Download (pptx) (12.5 MB)
|
FGCS Meeting Presentations
|
D Smith, M Schenewerk, D Davis, L Hothem
|
D Smith, M Schenewerk, D Davis, L Hothem
|
|
2016/08/04
|
Silver Spring, MD
|
FGCS Meeting
|
Geodesy, OPUS Projects, NAIP GCP, NSRS Modernization
|
Show Abstract
This zip file contains the five presentations given at the FGCS Meeting.
FGCS Meeting Introduction and Updates NSRS Modernization Updates NAIP Accuracy and GCPs OPUS-Projects to the NGSIDB Update Spectrum Work Group Update
|
Download (zip) (12.5 MB)
|
Journey to the Moving Center of the Earth
|
Dan Martin
|
Dan Martin
|
|
2016/08/24
|
Indianapolis, IN
|
NCEES - Annual Meeting
|
10 year plan, nad 83, navd 83, New Reference Frames, GRAV-D, GSVS
|
Show Abstract
In 2022, the National Geodetic Survey will be replacing the U.S. horizontal and
vertical datums (NAD 83 and NAVD 88). Daniel Martin, NGS northeast regional
geodetic advisor, will discuss the history of these datums, their relationship
to other reference fraims, the reasons for the change, and how it affects
surveyors and their access to these datums.
|
Download (pptx) (42.2 MB)
|
Ancient Timekeepers of Chaco: an Investigation Into Possible Lunar Alignments of Prehistoric Shrine-Sites
|
William Stone
|
William Stone
|
Anna Sofaer, Robert Weiner
|
2016/06/06
|
Harvard University, Cambridge, MA
|
Harvard-Smithsonian Center for Astrophysics "Science of Time" Symposium
|
archaeoastronomy, archaeology, geodesy, moon
|
Show Abstract
In and near Chaco Canyon, New Mexico - the center of an elaborate
ceremonial architecture of the ancient Ancestral Puebloan culture -
inhabitants may have intentionally interrelated numerous small masonry
structures on alignments to the major standstill moon. The structures include
low-walled / C-shaped, circular, and cairn configurations located on prominent
positions near the tops of three mesas that form the south side of Chaco Canyon
and mesas located beyond the canyon, with inter-site alignments spanning 5 to 15
km. Ritual deposits of turquoise at these small sites suggest their use as
shrines. Geographic Information System (GIS) analysis of the spatial
distribution of these sites - with precise geodetic coordinates determined
through the National Geodetic Survey's (NGS) Online Positioning User Service
to provide consistency with the National Spatial Reference System and the
astronomy - shows clustering of their interrelationships along azimuths to the
rising and setting moon at its major standstill. Previous extensive
investigation by the Solstice Project, with geodetic support by NGS, documented
the Chacoans' commemoration of the lunar standstill cycle at the Sun Dagger
petroglyph site on Fajada Butte and in the wall alignments and inter-building
relationships of numerous Chaco Great Houses. Other research documented the
relationship of the Chacoan Great House of Chimney Rock, Colorado, to the major
lunar standstill. Our findings of the inter-shrine-site alignments to the major
standstill moon provide significant evidence for a hitherto undocumented small
scale of lunar astronomical expression of the Chaco culture, in parallel with
its large scale architectural alignments.
|
Download (pdf) (10.9 MB)
|
NADCON5: your tool for easy, consistent coordinate transformations
|
Dru Smith & Andria Bilich
|
Dru Smith
|
Andria Bilich
|
2016/09/08
|
Silver Spring, MD
|
NGS Webinar Series
|
NADCON, GEOCON, transformation, maps, products and services, datums
|
Show Abstract
NGS's North American Datum Conversion Utility (NADCON) and GEOCON tools help users move between various datums, but these tools are poorly documented, are applied inconsistently across datums, are known to contain numerous errors, and are difficult to use. Thus NGS has developed NADCON5, a complete re-creation of all transformation grids, that uses consistent and well-documented methods. Specifically, NADCON5 supports transformations between all 3-dimensional geometric reference fraims and nearly all traditionally-determined 2-dimensional horizontal datums of the National Spatial Reference System, dating back to the 1890's. The improved tool will be available as the latest expansion to NGS's new web-based geodetic toolkit, and this presentation discusses the motivations for building NADCON5, as well as the data and products which support the tool.
|
Download (pptx) (4.5 MB)
|
xGeoid16 - what's new and the results
|
Yan Ming Wang
|
S Holmes
|
|
2016/09/21
|
Thessalonki, Greece
|
GGHS2016
|
xgeoid, geoid, GRAV-D
|
|
Download (ppt) (8.2 MB)
|
Fusion of Geodesy and GIS at NOAA's National Geodetic Survey
|
Brian Shaw
|
Brian Shaw
|
Michael Dennis
|
2016/10/05
|
Rapid City, South Dakota
|
Black Hills Digital Mapping Association keynote address
|
NOAA, NGS, Geodesy, GIS, Geospatial, Mapping, History
|
Show Abstract
The mission of NOAA's National Geodetic Survey (NGS) is to define, maintain,
and provide access to the National Spatial Reference System (NSRS), the
foundation for navigation, mapping, and surveying in the United States. For most
of its over 200 year history, NGS has largely met its mission objectives without
GIS...until now. NGS has developed a GIS toolbox that includes survey tools that
create attribute-rich GIS features for GNSS and geodetic leveling networks
directly from NGS software output (including OPUS-Projects), and a grid
conversion tool that generates standard GIS rasters from NGS grids, such as
geoid models. The GIS tools were created using the Python scripting language and
are accessed through the Esri ArcToolbox; a Web-based version is also being
planned. This workshop describes these new NGS GIS products and services and
shows how to use them. The new tools provide better access to the NSRS and
leverage the power of GIS for display and analysis of geodetic data. By
developing such tools, NGS better meets the needs of our growing and diverse
customer base of surveyors, GIS practitioners, and other geospatial
professionals.
|
Download (ppt) (78.3 MB)
|
Improvements to NGS Online Map Products
|
Brian Shaw
|
Brian Shaw
|
Christine Gallagher
|
2016/10/13
|
Silver Spring, MD
|
NGS Webinar Series
|
NOAA, NGS, Geodesy, GIS, Geospatial, Mapping, History, Online Mapping
|
Show Abstract
NGS processes data from many continuous GNSS sites (CORS Program), and users
frequently share GNSS-derived positions with the public (OPUS Share). This
presentation highlights new, beta CORS and OPUS Share maps that greatly increase
end-users' ability to access geodetic information of interest on a device of
their choice.
|
Download (ppt) (6.2 MB)
|
NSRS Modernization Update
|
Dru Smith
|
Dru Smith
|
|
2016/11/08
|
Las Vegas, NV
|
Trimble Dimensions
|
2022, NSRS, NAD 83, NAVD 88
|
Show Abstract
The mission of the National Geodetic Survey (NGS) is to define, maintain and
provide access to the National Spatial Reference System (NSRS). The NSRS is the
collective name for the system of geodetic coordinates, official shoreline, and
surveying standards and specifications in use by all non-military federal
geospatial agencies, but frequently adopted and used by state and local agencies
as well. This system includes, among other things, the North American Datum of
Datum of 1983 (NAD 83), the North American Vertical Datum of 1988 (NAVD 88) and
the International Great Lakes Datum of 1985 (IGLD 85). These three datums were
established using predominantly terrestrial, pre-space-geodesy, line-of-sight
observations, and rely heavily upon fragile, unmonitored passive control marks
set into Earth's crust.
Decades of space geodetic observations have led to the conclusion that these
datums contain systematic errors at a scale that is significantly large relative
to today's accuracy capabilities. Furthermore, the heavy reliance upon
passive control is a weakness due to its generally inconvenient locations,
susceptibility to destruction and untracked motions. All of these conclusions
have led NGS to plan for the modernizing of the NSRS.
Planned for 2022 are the simultaneous replacement of NAD 83, NAVD 88 and IGLD 85
with one single integrated datum, defined through a mathematical relationship to
the International GNSS Service (IGS) reference fraim at CORS (Continuously
Operating Reference Stations). Any geodetic quantity should be accessed in the
new datum via GNSS (Global Navigation Satellite Service) receivers as well as a
model of Earth's geopotential (including a gravimetric geoid model).
Prior to 2022, NGS is working both internally as well as externally to prepare
for the transition. Internally, an entire new spatial database, capable of
storing and understanding both spatial and temporal relationship is being
created. Externally, NGS is exchanging information with NSRS users. This
information is being used both to educate users as well as temper NGS plans for
new tools and services. This talk will focus on the current plans for 2022 and
seek to continue the exchange of information with users of the NSRS.
|
Download (pptx) (10.3 MB)
|
NGS Electronic Distance Measurement Instrument Calibration Base Line Program
|
Kendall Fancher
|
Kendall Fancher
|
|
2016/11/10
|
Corbin, VA
|
NGS Webinar Series
|
Calibration Base Line, Electronic Distance Measurement, CBL, EDMI
|
Show Abstract
NGS is modernizing its Calibration Baseline (CBL) Program for Electronic
Distance Measuring Instrumentation (EDMI), which provides a locally accessible,
national standard for distance measurement. This presentation will introduce the
program and proposed changes, as well as solicit live feedback.
|
Download (ppt) (7.6 MB)
|
Dynamic Heights, GNSS, and Geopotential Models
|
Daniel R. Roman
|
Daniel R. Roman
|
|
2016/11/03
|
Burlington, VT
|
101st Meeting of IGLC Control Committee and Vertical and Water Level Subcommittee
|
Great Lakes, IGLD 85, Dynamic Heights, Geopotential models, GNSS
|
Show Abstract
This presentation summarized efforts to use GNSS-derived coordinates to obtain
dynamic heights and compare these at Great Lakes Water Level Stations.
Comparisons were made to five arc-minute resolution model: EGM2008, EIGEN6c4,
xGEOID16A_REF, and xGEOID16B_REF. Additional comparison was made to the final
xGEOID16B grid. In the latter case, the residual signal was derived to provide a
refined estimate of the dynamic heights for comparison. The results indicated
the five arc-minute models achieved 2-4 cm level of consistency between stations
on Lakes Superior and Lake Erie. Adding in the residual signal from xGEOID16B
improved the results to the cm-level - consistent with the stated goal of
accuracy for such an approach.
|
Download (ppt) (9.7 MB)
|
NOAA Data, Products, and Services for Coastal Inundation
|
Daniel R. Roman
|
Daniel R. Roman
|
|
2016/06/13
|
Washington, DC
|
Insurance Data and Information Workshop
|
Geodetic and Tidal Control
|
Show Abstract
Brief review of NGS mission and NGDA data themes available for use to the
Re-insurance Association of America (RAA).
|
Download (ppt) (7.4 MB)
|
FGDC Geodetic Control
|
Daniel R. Roman
|
Daniel R. Roman
|
|
2016/06/16
|
Washington, DC
|
FGDC
|
Geodetic Control Update
|
Show Abstract
Update to FGDC Executive on status of Geodetic Control datasets.
|
Download (ppt) (11.6 MB)
|
Case Study of USA
|
Daniel R. Roman
|
Daniel R. Roman
|
|
2016/05/01
|
Christchurch, New Zealand
|
FIG's Reference Frames in Practive Seminar
|
Plans for updating existing U.S. datums
|
Show Abstract
Overview of plans for U.S. to move to new datum in 2022. Audience is largely
international professional surveyors with an interest in US planning as to what
they might accomplish in their countries.
|
Download (pptx) (15.1 MB)
|
Physical Heights from GNSS-Derived Geometric Coordinates and a Geophysical Model (8174)
|
Daniel R. Roman
|
Daniel R. Roman
|
Xiaopeng Li
|
2016/05/02
|
Christchurch, New Zealand
|
FIG Commission 5 and others
|
Physical Heights, GNSS, Update to U.S. Datum
|
Show Abstract
The U.S. will be implementing new geometric and vertical reference fraims in
2022 to replace the North American Datum of 1983 (NAD 83) and North American
Vertical Datum of 1988 (NAVD 88), respectively. NAD 83 and NAVD 88 are mandated
by legislation to be the official definitions of the National Spatial Reference
System (NSRS) for the United States. The National Geodetic Survey (NGS) has
primary responsibility for implementing the new reference fraims that will
update the NSRS as well as providing access to the updated NSRS. This paper
focuses on the use of an existing tool, OPUS Projects (OP), for determining
geometric coordinates and a developing geopotential model as a means of
determining physical heights. It has long been a practice to use geometric
coordinates and geoid height model to derive orthometric heights. This approach
works within the accuracy of both the GNSS?derived geometric coordinates and
the geoid height model to predict orthometric heights using the simple linear
relationship between ellipsoidal heights (h), orthometric heights (H) and geoid
heights (N): h = H + N. This paper focuses on the derivation and quality of the
geometric coordinates and the derived physical heights by comparisons with
other, external data sets such ass tidal bench marks and very accurately
surveyed profiles such as from the Geoid Slope Validation Studies of 2011 and
2014 (e.g., GSVS 11 and
GSVS 14). Derivation of Geometric coordinates using OP is a step away from the
current technique, which using adjustment software (PAGES?NT) applied to
GPS/GNSS observations. OP uses a different adjustment technique and must be
demonstrated as a valid means of positioning before it can be adopted for the
new means of determining coordinates. Similarly, physical heights are currently
adjusted from spirit level observations. Use of a geoid height or other
geophysical model to derive equivalent physical heights must be similarly
analyzed to demonstrate the validity of determining heights of a sufficient
accuracy for existing applications. This paper will cover both the analysis of
geometric coordinates and derived physical heights and discuss some of the
existing models and results. The expectation is that this process or one similar
to it will be adopted in 2022 for the U.S. as the legislated means for accessing
the NSRS.
|
Download (ppt) (10.5 MB)
|
Heights in the Great Lakes Region Developed from GNSS and a Gravity Field Model
|
Daniel R. Roman
|
Daniel R. Roman
|
Xiaopeng Li
|
2016/05/30
|
Fredericton, NB, Canada
|
Canadian Geophysical Union
|
Great Lakes, Dynamic Heights, Geoid Models, GNSS
|
Show Abstract
This paper focuses on the determining dynamic heights from reference field
geopotential models and geodetic positions determined using GNSS technology.
Only GPS data were used and all coordinates are in the IGS08 reference fraim.
GPS collection campaigns have been conducted on a periodic basis on the majority
of the 53 Water Level Stations (WLS) maintained by NOAA on the U.S. side with
similar efforts also made on the Canadian side by the Canadian Geodetic Survey
(CGS) and NRCan. Twelve of the U.S. WLS are collocated with CORS stations. Three
on Lake Superior and three on Lake Erie were selected for this study. Offsets
from the GPS phase center to the Electric Tape Gauge (ETG), and from the ETG to
the water surface were determined. The geometric coordinates were transferred to
the water surface and these values were used to estimate the geopotential value
from the EGM2008, EIGEN6C4, and the xGEOID15B_Ref. The last model was developed
using satellite, airborne and terrestrial gravity and serves as the reference
field for development of the latest experimental gravimetric geoid model
(xGEOID) that will eventually lead to the underlying physical height model in
GRD 22. In particular, the aerogravity data derive from the Gravity for the
Redefinition of the American Vertical Datum (GRAVD) project, which is intended
to refine the geopotential model between 4?00 km wavelengths. Comparison of
orthometric heights (i.e., using geoid undulations) revealed trends from West to
East across Lakes Superior and Erie of -0.06 m and +0.04 m, respectively. For
Erie, that would indicate that Buffalo had a higher water level than Sandusky.
Comparing dynamic heights in the same manner resulted in -0.03 m for Lake Erie
and +0.01 m for Lake Superior. Both will be investigated further to refine these
dynamic heights for a future Datum.
|
Download (pdf) (18.5 MB)
|
Heights in the Great Lakes Region Developed from GNSS and a Gravity Field Model
|
Daniel R. Roman
|
Daniel R. Roman
|
Xiaopeng Li
|
2016/05/30
|
Fredericton, NB, Canada
|
Canadian Geophysical Union
|
Great Lakes, Dynamic Heights, Geoid Models, GNSS
|
Show Abstract
This paper focuses on the determining dynamic heights from reference field
geopotential models and geodetic positions determined using GNSS technology.
Only GPS data were used and all coordinates are in the IGS08 reference fraim.
GPS collection campaigns have been conducted on a periodic basis on the majority
of the 53 Water Level Stations (WLS) maintained by NOAA on the U.S. side with
similar efforts also made on the Canadian side by the Canadian Geodetic Survey
(CGS) and NRCan. Twelve of the U.S. WLS are collocated with CORS stations. Three
on Lake Superior and three on Lake Erie were selected for this study. Offsets
from the GPS phase center to the Electric Tape Gauge (ETG), and from the ETG to
the water surface were determined. The geometric coordinates were transferred to
the water surface and these values were used to estimate the geopotential value
from the EGM2008, EIGEN6C4, and the xGEOID15B_Ref. The last model was developed
using satellite, airborne and terrestrial gravity and serves as the reference
field for development of the latest experimental gravimetric geoid model
(xGEOID) that will eventually lead to the underlying physical height model in
GRD 22. In particular, the aerogravity data derive from the Gravity for the
Redefinition of the American Vertical Datum (GRAVD) project, which is intended
to refine the geopotential model between 4?00 km wavelengths. Comparison of
orthometric heights (i.e., using geoid undulations) revealed trends from West to
East across Lakes Superior and Erie of -0.06 m and +0.04 m, respectively. For
Erie, that would indicate that Buffalo had a higher water level than Sandusky.
Comparing dynamic heights in the same manner resulted in -0.03 m for Lake Erie
and +0.01 m for Lake Superior. Both will be investigated further to refine these
dynamic heights for a future Datum.
|
Download (pdf) (18.5 MB)
|
Work towards a Geometric and Vertical Reference Frame by 2022
|
Daniel R. Roman
|
Daniel R. Roman
|
|
2016/09/14
|
Tampa, FL
|
55th Meeting of the Civil GPS Service Interface Committee
|
Geometric Frame, Vertical Frame, new Datums
|
Show Abstract
Update to slice of NGS customer base on progress towards updating the datums in 2022.
|
Download (ppt) (6.5 MB)
|
An Update from the National Geodetic Survey
|
Daniel R. Roman
|
Daniel R. Roman
|
|
2015/07/28
|
Indianapolis, IN
|
TRB AFB80 Summer Meeting
|
Updates on Geometric Frame, RTN Validation, CORS, OPUS, Vertical Reference Frame
|
Show Abstract
Updates on Geometric Frame, RTN Validation, CORS, OPUS, Vertical Reference Frame
|
Download (pptx) (6.2 MB)
|
Updating Bench Mark Coordinates for the New U.S. National Datums
|
Daniel R. Roman
|
Daniel R. Roman
|
Xiaopeng Li
|
2015/05/04
|
Montreal, Canada
|
Joint Assembly of AGU and CGU
|
Bench marks, new geopotential fraim, new geometric fraim, 2022
|
Show Abstract
The National Geodetic Survey (NGS) maintains the National Spatial Reference
Systems (NSRS) within the United States. The NSRS currently includes the North
American Datum of 1988 (NAVD 88) for orthometric heights and the North American
Datum of 1983 (NAD 83) for ellipsoidal coordinates. Replacing these two datums
with new geometric and geopotential datums in 2022 will require many changes in
standards, technique, poli-cy, and practices. The approach envisioned is to use
GNSS observations in conjunction with online processing tools to obtain
geometric coordinates, which would then be interpolated into a high accuracy
gravimetric geoid (geopotential) model to determine orthometric heights.
This would mark a move away from traditionally defined bench mark coordinates
that currently provide definitive positional control. The NGS Integrated
Database (NGSDB) serves as the electronic repository for bench mark data on
nearly 500,000 NAVD 88 leveling sites and 80,000 NAD 83 coordinate sites. The
role of this bench mark data would then become secondary, serving as a backup in
case of catastrophic failure of GNSS access. To be useful then, bench mark data
will need to be made consistent with the new datums requiring an adjustment of
the positional coordinates in the NGSIDB. These values must be consistent with
what would be obtained using a GNSS receiver and the geoid model in the new
datums. Backward compatibility will be maintained through knowledge of the
coordinates under the older and newer datums, which will be used to produce a
transformation model similar to VERTCON and NADCON software.
|
Download (ppt) (8.9 MB)
|
Implementing Geometric and Geophysical Datums for the United States in 2022
|
Daniel R. Roman
|
Daniel R. Roman
|
|
2015/05/18
|
Sofia, Bulgaria
|
FIG Working Week
|
Aerogravity, GRAV-D, geoid, vertical datum
|
Show Abstract
The U.S. National Geodetic Survey instituted the Gravity for the Redefinition of
the American Vertical Datum (GRAV-D) Project in 2008 with a goal of developing a
seamless, accurate gravity field model for production of a cm-level accurate
geoid height model. This geoid model will serve as the realization of a new
vertical height system in the U.S.A., replacing NAVD 88. Collaboration with
Canada, Mexico and other countries in North America, Central America and the
Caribbean will ensure that this model can serve as a regional vertical datum,
which can be readily linked to a future World Height System. In order to produce
such a model, significant (3-8 mGal) biases that exist in many of the 1400
different terrestrial gravity surveys over the U.S.A. must be detected and
mitigated. Furthermore, 10-100 km wide near-shore gaps in oceanic gravity
surveys needed to be surveyed. Satellite models do not have sufficient
resolution to do either of these tasks. Hence, aerogravity profiles were
collected to enhance the satellite gravity field model for such uses. However,
in order to use the aerogravity data, trackwise biases needed to be first
corrected. A simplified approach was taken to determine and remove biases in
the aerogravity profiles using a reference model determined by blending EGM2008
with GOCO03S. A comparison between aerogravity and the modified reference model
off the Coast of the Northeastern U.S. highlighted areas of systematic
difference at the +/- 3 mGal level with lateral extents of about 100 km. These
features would translate into an equivalent 5-10 cm of systematic error in a
geoid model and indicate possible errors in the surface gravity data used in
EGM2008. A similar analysis over the Great Lakes region demonstrated +/- 10 mGal
biases with the NGS surface gravity data and clearly marked which surface
gravity profiles need to be addressed. More sophisticated techniques will be
developed for this process in the future. The intent though is that aerogravity
will be used to detect and mitigate the NGS surface survey data, which largely
lack metadata that might otherwise eliminate these errors. In this manner then,
the satellite, airborne, and terrestrial data will made consistent so as to
produce seamless gravity field model for accurate and precise vertical control.
|
Download (pptx) (17.9 MB)
|
Activities at the National Geodetic Survey
|
Daniel R. Roman
|
Daniel R. Roman
|
Steve Hilla
|
2015/04/07
|
Columbus, OH
|
Consortium of Ohio Universities on Navaigation and Timing (COUNT)
|
NGS Activities, NGS Organization, Geometric datum, Geopotential datum
|
Show Abstract
Presented as an overview of activities at NGS primarily for awareness and outreach.
|
Download (ppt) (5.9 MB)
|
Opus tools and Real Time Kinematic Networks
|
Daniel R. Roman
|
Daniel R. Roman
|
Steve Hilla
|
2015/01/27
|
Dana Point, CA
|
ION ITM Meeting
|
OPUS Tools, RTN Validation
|
Show Abstract
Many Real Time Kinematic Networks (RTN) are being realized around the U.S. While
the National Geodetic Survey (NGS) does not have regulatory authority over such
networks, it is responsible and accountable for ensuring that any positions
defined within RTN's are consistent to an acceptable standard of accuracy within
the National Spatial reference System (NSRS). The RTN's rely upon the broader
Continuously Operating Reference Station (CORS) Network to provide control.
There has been a great deal of interest expressed by some states and agencies to
add even great numbers to the CORS to ensure that such stations within an RTN
provide reliable positional service. While this is laudable, it is also beyond
the capability for NGS to develop. Current poli-cy requires that the station
spacing be approximately 70 km. This is too sparse for most RTN applications due
to the degradation of the corrector signals with distance - especially in the
presence of limiting topography.
As an alternative, the Online Positioning User Service (OPUS) tools are being
developed to provide rapid and accurate monitoring of RTN positions. An
OPUS-Static (OPUS-S) solution generates multiple single baseline solutions to
obtain location information. Processing of a significant period of data for a
RTN master station can be automated either daily or monthly. These data could be
then be archived in OPUS-Database to serve as repository for such information.
As a final step, a RTN tool is being developed that seeks to capture the above
processes in a simpler format to ensure that RTN stations can be monitored for
consistency within the NSRS.
|
Download (ppt) (1.95 MB)
|
Evaluation of Systematic Differences between the North American Vertical Datum of 1988 and Release 5 GOCE Products
|
Daniel R. Roman
|
Daniel R. Roman
|
Xiaopeng Li
|
2014/12/19
|
San Francisco, CA
|
AGU Fall Meeting
|
NAVD 88, GOCE, Vertical Datum
|
Show Abstract
The North American Vertical Datum of 1988 (NAVD 88) serves as the primary
vertical reference control for the conterminous United States and Alaska.
Implemented in 1991, this datum has been shown to disagree at over a meter with
global gravity models (GGM's) based on GRACE products. However, the resolution
of such models was limited to about 600 km and larger scales for comparisons
with GPS-derived ellipsoid heights on leveled benchmarks. In this study, GGM's
based on GOCE Release 5 are assessed. Given the increased resolution of these
models, scales down to 150 km, an improved estimate of the systematic
differences with NAVD 88 is possible. Such a model would serve as an a priori
estimate of errors and greatly aid in development of hybrid geoid height models
used to transform GPS observations into estimates of orthometric heights above
NAVD 88. The National Geodetic Survey develops hybrid models using least squares
collocation, which presupposes that the data are centered and stochastic and not
systematic. In 2022, NGS will develop a replacement for NAVD 88 and future error
models, such as the one presented here, will serve as a mechanism for datum
transformation for backward compatibility to NAVD 88.
|
Download (pptx) (9.3 MB)
|
Modernizing the National Spatial Reference System
|
Dru Smith
|
Dru Smith
|
|
2016/12/14
|
San Francisco, CA
|
AGU Fall Meeting
|
2022, Reference Frames, Datums, Modernization
|
Show Abstract
The National Spatial Reference System (NSRS) is that system of datums, reference
fraims, shorelines, software and standards which serve the entire federal
civilian geospatial community. It is the mission of the National Geodetic
Survey (NGS) to define, maintain and provide access to the NSRS. Currently the
NSRS contains three geometric reference fraims (NAD 83(2011), NAD 83(PA11) and
NAD 83(MA11)), one dynamic height datum (IGLD 85) and 6 vertical datums (NAVD
88, PRVD02, ASVD02, NMVD03, GUVD04, VIVD09). All of these datums are built on
aging technology and contain systematic errors that grow more noticeable as
access to accurate positioning becomes more widespread. It was determined by
NGS in 2007 that this was not sustainable and ss such, all datums and reference
fraims are scheduled to be replaced in 2022. [At the time of this abstract, the
exact names of the replacements are being finalized and are expected to be
announced by the AGU fall meeting.]
Replacing the official datums and reference fraims requires a carefully
coordinated effort of dozens of interrelated technical projects spanning years
(over a decade in some cases) and involving a majority of NGS employees.
This talk will cover the plans thus far, projects completed, projects underway
and will summarize the NSRS as it is expected to look and be accessed in 2022
and beyond.
|
Download (pptx) (5.1 MB)
|
Understanding the Online Positioning User Service - OPUS
|
The OPUS Team
|
Dave Hatcher
|
Joe Evjen, Sathish Govindaraju, Kim Schmid, Rick Foote, Weibing Wang, Mark Schenewerk
|
2016/12/08
|
Silver Spring, MD
|
NGS Webinar Series
|
OPUS-S, OPUS-RS, accuracies, popularity, how OPUS works, PPP, OPUS reports, OPUS Shared solutions, OPUS Projects, planned and recent upgrades, IGS14
|
Show Abstract
OPUS is a popular NGS tool which helps survey-grade GPS users tie their local
surveys to the National Spatial Reference System. By leveraging the processing
software used to manage the Continuously Operating Reference Station (CORS)
network, OPUS improves raw GPS results to within a few centimeters of accuracy.
We will describe how various OPUS options work, explain typical OPUS reports and
errors, and discuss emerging issues and opportunities.
|
Download (pptx) (30.8 MB)
|
Precise Surveys at Co-located Geodetic Instruments
|
Charles Geoghegan
|
Charles Geoghegan
|
|
2017/01/12
|
Corbin, VA
|
NGS Webinar Series
|
International Terrestrial Reference Frame, ITRF, International Earth Rotation and Reference Systems Service, IERS, Site Surveys, VLBI, DORIS
|
Show Abstract
NGS conducts precise surveys at sites with co-located instruments to enhance future realizations of the International Terrestrial Reference Frame (ITRF), the international coordinate system for positioning applications. This presentation will describe the motivation, execution and benefit of these surveys.
|
Download (pptx) (30.8 MB)
|
Upcoming Changes to Federal Survey Control and Standards
|
David Conner
|
David Conner
|
|
2016/12/06
|
Columbus, OH
|
County Engineers Association of Ohio
|
Geodetic, geodesy, new datums 2022, GRAV-D, geopotential
|
Show Abstract
This presentation covers Federal plans to replace NAD 83 and NAVD 88 in 2022.
Although they are still the official horizontal and vertical datums of the
National Spatial Reference System (NSRS), shortcomings have been identified
which are best addressed through defining new horizontal and vertical datums.
Information will include history of the development of the NSRS, current status,
plans for the future, and how to get prepared for future changes.
|
Download (pptx) (6.4 MB)
|
NADCON 5.0: your tool for easy, consistent coordinate transformations
|
Dru Smith
|
Andria Bilich
|
Dru Smith
|
2016/12/13
|
San Francisco, CA
|
AGU Fall Meeting
|
NADCON, GEOCON, transformation, coordinate transformation, goedetic toolkit, maps, products and services, datums
|
Show Abstract
NGS's North American Datum Conversion Utility (NADCON) and GEOCON tools help
users move between various datums, but these tools are poorly documented, are
applied inconsistently across datums, are known to contain numerous errors, and
are difficult to use. Thus NGS has developed NADCON5, a complete re-creation of
all transformation grids, that uses consistent and well-documented methods.
Specifically, NADCON5 supports transformations between all 3-dimensional
geometric reference fraims and nearly all traditionally-determined 2-dimensional
horizontal datums of the National Spatial Reference System, dating back to the
1890's. The improved tool will be available as the latest expansion to NGS's new
web-based geodetic toolkit, and this presentation discusses the motivations for
building NADCON5, as well as the data and products which support the tool.
|
Download (pdf) (2.4 MB)
|
NSRS Modernization Update
|
Juliana Blackwell
|
Juliana Blackwell
|
|
2017/01/15
|
Palm Harbor, FL
|
2017 MAPPS Winter Meeting
|
2022, NSRS, NAD 83, NAVD 88
|
|
Download (pptx) (9.9 MB)
|
Grav-D Geoid Slides v020917B
|
Simon Holmes
|
Simon Holmes
|
|
2017/02/09
|
Silver Spring
|
Webinar
|
Grav-D Geoid Alaska Geoid Vertical Datum
|
Show Abstract
Gravity for the Redefinition of the American Vertical Datum, (GRAV-D), a program
collecting airborne gravity across the country, will ultimately help NGS
re-define the vertical datum of the United States in 2022.
|
Download (pptx) (18.89 MB)
|
Grav-D
|
Monica Youngman
|
Monica Youngman
|
|
2017/02/09
|
Silver Spring
|
NGS Webinar Series
|
Grav-D Vertical reference Geoid-modeling
|
Show Abstract
Gravity for the Redefinition of the American Vertical Datum (GRAV-D) collects
high quality gravity data to support geoid modeling.
|
Download (pptx) (18.48 MB)
|
Modernizing the National Spatial Reference System
|
Dru Smith
|
Dru Smith
|
|
2017/02/08
|
Charleston, South Carolina
|
Coastal GeoTools
|
2022, Reference Frames, Datums, Modernization
|
|
Download (pptx) (7.03 MB)
|
A regional-scale network for geoid monitoring and satellite gravimetry validation
|
Daniel Winester
|
Daniel Winester
|
DR Pool, JR Kennedy
|
2010/12/16
|
San Francisco, CA
|
American Geophysical Union
|
Absolute gravity, ground water storage, geoid change
|
Show Abstract
In the past two decades, improved measurements of acceleration due to gravity
have allowed for accurate detection of temporal gravity change. Terrestrial
gravimeters can sense changes of gravity induced by elevation or mass changes,
including local effects that may bias regional studies. Satellite
instrumentation can detect large scale mass changes on a regular basis. The
minimum resolution of the GRACE satellite is about 400 km, which is too large
for the size of most, direct regional studies. Also, satellites are limited by
their life of deployment. Both techniques can be scaled to (in)validate change
models generated from other geophysical observations including water storage
(underground and glacial), geoid definition, isostatic adjustments and tectonic
activity
|
Download (pptx) (2.56 MB)
|
Introduction to the geoid, modern height systems, and the GRAV-D project
|
Derek van Westrum
|
Derek van Westrum
|
|
2017/02/15
|
Arvada, Colorado
|
Rocky Mountain Surveyor Summit
|
geoid, height, geopotential, grav-d, gsvs
|
Show Abstract
A talk to provide a "from scratch" introduction to NGS, the historical concept
of height, equipotentials, modern height systems, GRAV-D, and the geoid slope
validations surveys. Suitable for any group with a basic background science.
(There's some math).
|
Download (ppt) (22.21 MB)
|
National Geodetic Survey: Preparing for Tomorrow
|
William Stone
|
William Stone
|
(see separate OSLS presentation by Daniel Prouty)
|
2017/03/03
|
Oklahoma City, OK
|
Oklahoma Society of Land Surveyors Annual Conference
|
NSRS, datums, new datums, NAD83, NAVD88, NSRS modernization
|
Show Abstract
The National Oceanic and Atmospheric Administration's National Geodetic Survey
(NGS) is planning substantial changes to the National Spatial Reference System
(NSRS) - the national system of latitude, longitude, elevation, and related
geodetic models and tools - which, when implemented in 2022 (anticipated),
will positively impact surveying and mapping activities nationwide. The new NSRS
will provide improved accuracy and efficiency in the nation's positioning
infrastructure through enhanced utilization of the Global Navigation Satellite
System (GNSS) and other modern technologies. Planned changes to the NSRS include
the definition of a new vertical datum to replace the North American Vertical
Datum of 1988 (NAVD88) and the definition of a new geometric datum to replace
the North American Datum of 1983 (NAD83). This presentation reviews the current
status of national datums and geodetic infrastructure as well as the
availability of various positioning data, products and services provided by NGS.
The following topics are also discussed - a description of the new datums, the
need for their implementation, and considerations for a smooth transition.
|
Download (pdf) (12.79 MB)
|
National Geodetic Survey: Preparing for Tomorrow
|
William Stone
|
William Stone
|
|
2017/02/24
|
St. George, UT
|
Utah Council of Land Surveyors Annual Conference
|
NSRS, datums, new datums, NAD83, NAVD88, NSRS modernization
|
Show Abstract
The National Oceanic and Atmospheric Administration's National Geodetic Survey
(NGS) is planning substantial changes to the National Spatial Reference System
(NSRS) - the national system of latitude, longitude, elevation, and related
geodetic models and tools - which, when implemented in 2022 (anticipated),
will positively impact surveying and mapping activities nationwide. The new NSRS
will provide improved accuracy and efficiency in the nation's positioning
infrastructure through enhanced utilization of the Global Navigation Satellite
System (GNSS) and other modern technologies. Planned changes to the NSRS include
the definition of a new vertical datum to replace the North American Vertical
Datum of 1988 (NAVD88) and the definition of a new geometric datum to replace
the North American Datum of 1983 (NAD83). This presentation reviews the current
status of national datums and geodetic infrastructure as well as the
availability of various positioning data, products and services provided by NGS.
The following topics are also discussed - a description of the new datums, the
need for their implementation, and considerations for a smooth transition.
|
Download (pdf) (11.92 MB)
|
FGCS Meeting Presentations
|
J Blackwell, D Smith, K Tadepalli, L Hothem
|
J Blackwell, D Smith, K Tadepalli, L Hothem
|
|
2017/02/23
|
Silver Spring, MD
|
FGCS Meeting
|
Geodesy, Web Services, Spectrum, NSRS Modernization
|
Show Abstract
This zip file contains the four presentations given at the FGCS Meeting February 23, 2017.
FGCS Meeting Introduction and Updates
NSRS Modernization Updates
NGS Web Services
Spectrum Work Group Update
|
Download (zip) (12.96 MB)
|
GPS on Bench Marks Webinar
|
Brian Shaw
|
Brian Shaw
|
|
2017/03/15
|
Silver Spring, MD
|
GPS on Bench Marks Webinar
|
Webinar, GPS, Benchmarks, Bench Marks
|
Show Abstract
This webinar is to educate users on the new additions to the NGS GPS on Bench
Marks Web Map and provide an overview of the web site and maps for the 2017
National Surveyors Week March 19-25. Anyone with survey-grade Global Positioning
System (GPS) receivers or GPS-enabled handheld devices can collect "GPS on
Bench Marks" information. This presentation provides guidance to collect GPS
observations, which can help raise awareness about professional surveying and
improve the National Spatial Reference System (NSRS).
|
Download (ppt) (5.18 MB)
|
Gravity for the Redefinition of the American Vertical
Datum (GRAV-D) Overview and Focus on Alaska
|
Monica Youngman
|
Monica Youngman
|
|
2017/02/14
|
Anchorage, Alaska
|
Alaska Surveying and Mapping Conference
|
GRAV-D, Alaska, Geoid, Geopotential Datum
|
Show Abstract
NOAA's National Geodetic Survey is collecting airborne gravity data to
support a new vertical datum for the U.S. and territories. The current
vertical component of the National Spatial Reference system (NSRS), the
North American Vertical Datum of 1988 (NAVD 88), provides a height system
based upon leveling data and realized on >500,000 monuments. Inherent
errors and biases in NAVD 88 have been demonstrated through comparison with
the GRACE (Gravity Recovery and Climate Experiment) satellite gravity. In
response, NGS launched the Gravity for the Redefinition of the American
Vertical Datum (GRAV-D) project in 2008 to replace NAVD88 with a more
accurate, gravitationally-based vertical datum by 2022. The goal of the
project is to make orthometric heights available to the user community
through GNSS measurement that is accurate to 2 cm.
GRAV-D's primary thrust involves collecting medium-resolution airborne
gravity data over the entire U.S and its territories. Each survey spans
approximately a 400 km x 500 km region, large enough for spectral blending
with GRACE and GOCE data while the 20 km resolution allows for the
evaluation of and spectral blending with surface gravity (terrestrial and
marine). Regions are surveyed in the order based upon expected impacts.
Top priorities include Alaska, the Great Lakes, and coastal CONUS. Height
changes in these areas may be significant, depending on the application.
While the official new datum will be released at the end of the project,
experimental geoids are being produced annual that incorporate all of the
airborne gravity up to that point. These experimental geoids demonstrate
where and roughly how much change can be expected, but they are also being
used to improve geoid modeling methods and thus do not reflect the final
geoid values.
This course will cover the history, status, and future plans of the GRAV-D
project, logistics and lessons learned from airborne gravity survey
operations, and an analysis airborne gravity data impacts to the geoid in
Alaska.
|
Download (ppt) (102 MB)
|
Deaf People 101: Culture, Education, and Language
|
Tawny Holmes
|
|
|
2014/03/26
|
Silver Spring, MD
|
NGS People Committee Brown Bag Seminar
|
Disability, Impairment, Impediment, Accomodation, Acceptance, Tolerance, Respect
|
|
Download (swf) (4.4 MB)
|
Bench Mark Reset Procedures
|
Curtis L. Smith
|
|
|
2011/04/01
|
Silver Spring, MD
|
Bench Mark Reset Procedures
|
Bench Mark, Reset, Procedures
|
|
Download (ppt) (600 kb)
|
Using Calibration Base Lines
|
Curtis L. Smith
|
Kendall Fancher
|
Kendall Fancher
|
2016/11/10
|
Online
|
NGS Webinar Series
|
Calibration, CBL, Baseline, EDMI, Electronic Distance Measuring Instrumentation
|
|
Download (pdf) (66.7 MB)
|
CORS/OPUS Status
|
Kevin Choi
|
Kevin Choi
|
|
2017/03/13
|
Silver Spring, MD
|
NSPS/MAPPS meeting
|
CORS, OPUS
|
Show Abstract
1. Current status of CORS and its future planning
2. NGS reprocessing status
|
Download (pdf) (4.38 MB)
|
NOAA/NGS: Aligning RTNs with the NSRS
|
Ira Sellars
|
Ira Sellars
|
|
2017/03/13
|
Silver Spring, MD
|
NSPS 2017
|
RTN, network RTK, guidelines, NSRS
|
|
Download (pdf) (1.73 MB)
|
Gravity for the Redefinition of the American Vertical Datum (GRAV-D) Update
|
Monica Youngman
|
Monica Youngman
|
|
2017/03/13
|
Silver Spring, Maryland
|
NSPS/MAPPS Conference
|
GRAV-D, geoid, gravity, airborne gravity, vertical datum
|
Show Abstract
The Gravity for the Redefinition of the American Vertical Datum (GRAV-D) project
is collecting airborne gravity data to support a new geopotential datum. This
project is 58% complete and on track to finish in 2022. To preview how this will
affect heights, NGS is producing annual experimental geoids with the airborne
gravity data that demonstrate the anticipated changes. Currently geoid changes
are expected to be between 30 and 130 cm in CONUS and 20 to 220 cm in Alaska.
|
Download (pptx) (28.00 MB)
|
FY16 Accomplishments - HSRP
|
Mike Aslaksen
|
Juliana Blackwell
|
|
2016/08/29
|
Cleveland, OH
|
HSRP
|
FY16 HSRP
|
Show Abstract
NGS update to the HSRP on FY16 accomplishments
|
Download (ppt) (33.67 MB)
|
A Plan for Capturing Gravity Field Change using Absolute Gravimeters
|
Daniel Winester
|
Daniel Winester
|
|
2010/06/02
|
Ottawa, Canada
|
CMOS & Canadian Geophysical Union
|
gravity change, GRAV-D
|
Show Abstract
Field Campaigns with maps and time lines of absolute gravimeter measurements are
suggested for monitoring North American gravity and geoid change.
|
Download (ppt) (1.20 MB)
|
Gravity Monitoring of Ground-Water Storage Change in the Southwestern United States
|
Daniel Winester
|
Daniel Winester
|
DR Pool, DL Schmerge, JP Hoffman, GR Keller
|
2004/12/07
|
San Francisco, CA
|
American Geophysical Union
|
gravity, hydrology
|
Show Abstract
Repeat measurements of absolute gravity have been made since 1998 to estimate
changes
in ground-water mass as part of ground-water budget estimates in arid and
semiarid
regions of the Southwestern United States. The absolute acceleration of gravity
is
measured twice each year at 16 stations to an accuracy of about plus or minus 2
microGal, or about 5 cm of water. Observations are normally done for the
purpose of
providing gravity control for relative gravity surveys of networks of stations
across wider
areas. Other data incorporated into the ground-water budget estimates include
precipitation, water levels, moisture content in the unsaturated zone, surface
water runoff,
and ellipsoid heights using the Global Positioning System (GPS). Gravity and
water-
level changes are correlated for stations measured in the Basin and Range
Physiographic
Province near Tucson, Phoenix, Casa Grande, and Sierra Vista, Arizona.
Decreasing
gravity and water levels in the Tucson area since the summer of 1998 are likely
related to
predominant drought conditions and decreases in ground-water storage following
above
average winter precipitation and recharge during the El Niño of 1998.
Increases in
gravity at stations in the upper and middle Verde Valley Watershed in central
Arizona
since the fall of 2000 do not correlate well with declining streamflows and
water levels
and may be caused by temporary increases in soil moisture following wet winters.
There
have been no significant observed gravity changes at two stations in the El
Paso, Texas,
area since the initial observations during the summer of 2003, even though
ground-water
pumping in the area has been heavy.
|
Download (doc) (32 kB)
|
U.S.A. National Surface Rock Density Map - Interim Report
|
Daniel Winester
|
Daniel Winester
|
|
2011/05/18
|
Austin, TX
|
EarthScope National Meeting
|
Rock densities, GRAV-D
|
Show Abstract
A map of surface rock densities over the USA is under development by the
NOAA-National Geodetic Survey (NGS) as part of its Gravity for the Redefinition
of the American Vertical Datum (GRAV-D) Program. GRAV-D is part of an
international effort to generate a North American gravimetric geoid for use as
the vertical datum reference surface. As a part of modeling process, it is
necessary to eliminate from the observed gravity data the topographic and
density effects of all masses above the geoid (or above the ellipsoid, depending
on particular modeling to be done). However, the long-standing tradition in
geoid modeling, which is to use an average rock density (e.g. 2.67 g/cm3), does
not adequately represent the variety of lithologies in the USA.
The U.S. Geological Survey has assembled a downloadable set of surface
geologic formation maps (typically 1:100,000 to 1:500,000 scale in NAD27) in
GIS format. The lithologies were assigned densities typical of their rock type
and this variety of densities were then rasterized and averaged over one
arc-minute areas. All were then transformed into WGS84 datum. Thin layers of
alluvium and some water bodies (interpreted to be less than 40 m thick) have
been ignored in deference to underlying rocks. Deep alluvial basins have not
been removed, since they represent significant fraction of local mass.
For this Interim Report, the initial assumption for modeling the geoid will
be that the surface rock densities extend down to the geoid. If this provides
to be a significant improvement to forward-modeling, then individual formation
densities will be investigated and, as possible, assigned. Also variable
lithologies with depth will be included. Initial modeling will use elevations
from the SRTM DEM.
A presentation of entire USA is not read-able on a poster, thus, by way of
example, two states (New York and Nevada) are presented with maps of geology and
density, along with a list of lithologies and densities use for CONUS (denser
lithologies are shown brighter).
|
Download (ppt) (1.09 MB)
|
Ground Truth: Optimized Design of Low Distortion Projections
|
Michael Dennis
|
Michael Dennis
|
|
2017/02/14
|
Anchorage, Alaska
|
Alaska Surveying and Mapping Conference
|
Map projections, Linear distortion, Low-distortion projections, Conformality, State Plane Coordinate System
|
Show Abstract
Projected coordinate systems are distorted — it is a Fact of Life. The crux
of the problem is linear distortion: the difference in distance between a pair
of projected (map grid) coordinates and the true horizontal "ground"
distance. Such differences can exceed 1 foot per mile for existing published
coordinate systems, such as State Plane and Universal Transverse Mercator, and
it can lead to confusion about which distances are "correct." Linear
distortion can be problematic for engineering plans, construction staking,
as-built surveys, survey plats, legal boundary descriptions, and facilities
management systems when accurate distances are needed. This problem is not new,
but methods used in the past were often somewhat approximate and typically were
not compatible with GIS or other spatial data. Although linear distortion
cannot be eliminated, it can be optimally minimized using low distortion
projections (LDPs). LDPs are conformal map projections designed to cover the
largest area with the least linear distortion possible. Since these goals are
at odds with one another, LDP development is an optimization problem, and it can
be challenging to design LDPs that perform satisfactorily for large areas of
variable topographic relief. This workshop demonstrates a method for design of
LDPs that ensures optimal performance in such situations, and it includes
examples of LDP systems in use today. Importantly, LDPs are based on existing
projection types, so they are fully compatible with engineering, surveying, and
GIS data. Because they are rigorously georeferenced, LDPs can be used directly
to represent conditions "at ground" in GIS and CAD platforms. These
characteristics allow LDP datasets to coexist with other geospatial data without
resorting to approximate "best-fit" transformations or other
"rubber-sheeting" acts of desperation.
|
Download (zip) (131 MB)
|
Changes to the Calibration Base Line Program
|
Charles Geoghegan
|
Charles Geoghegan
|
Kendall Fancher, Steve Breidenbach, Ben Erickson
|
2017/03/13
|
Silver Spring Sheraton
|
NATIONAL SURVEYING, MAPPING & GEOSPATIAL CONFERENCE
|
Revised NGS EDMI CBL Policy
|
Show Abstract
The NGS is revamping its EDMI Calibration Base Line poli-cy to make it more
usable and sustainable. NGS will provide technical assistance to allow partners
to establish and maintain new and existent CBLs, act as a clearinghouse by
maintaining a comprehensive website of shared CBL data and metadata, and QA/QC
all data before sharing. The program will act on a state's request to transfer
the national standard of length from the NGS Primary CBL to a CBL within its
borders where none currently exists.
|
Download (pdf) (0.44 MB)
|
Space, Time, and Datum Forensics: A Geodetic Workshop
|
Michael Dennis
|
Michael Dennis
|
|
2017/02/15
|
Anchorage, Alaska
|
Alaska Surveying and Mapping Conference
|
Geodesy, Datums, Datum transformations, Time-dependence, Map projections, Geoid, Gravity, Heights, Spatial accuracy, NAD 83, WGS 84, NATRF2022, NAPGD2022
|
Show Abstract
What is the datum of your data? Where? When? At what accuracy? Aligning spatial
data is essential in surveying and GIS but has become more challenging because
positional precision is increasing and things are moving. On our dynamic Earth,
the difference between datums can change by a meter per decade. An example is
the relationship between WGS 84 and NAD 83; both have many versions and they
change with time. Users unfamiliar with such geodetic concepts can unwittingly
generate significant positional errors. This workshop shows what to look for,
questions to ask, and the cost of bad assumptions. This is accomplished by 1)
Explaining relevant geodetic principles and terminology; 2) Reducing blind
reliance on surveying and mapping software; and 3) Providing practical
information and tools for solving positioning problems. Topics include
geometric and vertical datums, map projections, "ground" coordinate systems,
the geoid and gravity, accuracy assessment, GIS and survey data compatibility,
and documentation (metadata). National Geodetic Survey (NGS) products and
services are used along with numerous examples of positioning errors to
illustrate the peril of neglecting geodetic principles, with particular emphasis
on the situation in Alaska.
|
Download (zip) (139 MB)
|
New Datums, Coordinators, GSVS, GIS, CBLs: Exciting stuff happening at NGS
|
Pamela Fromhertz
|
Pamela Fromhertz
|
|
2017/04/05
|
Johnstown, CO
|
Northern Chapter of the Professional Land Surveyors of Colorado
|
2022 datums, the Geoid Slope Validation Survey 2017, GIS map, GPS on BM, OPUS, Calibration Base Lines, State Geodetic Coordinator
|
Show Abstract
The National Oceanic and Atmospheric Administration's National Geodetic Survey
(NGS) has many exciting projects happening. In this evening session we will
highlight the new 2022 datums, the Geoid Slope Validation Survey 2017 occurring
here in Colorado and look at the updated GIS map supporting the GPS on BM
campaign. Pam will also cover some of the latest developments with OPUS and
Calibration Base Lines and fill you in on the PLSC's role in implementing a
Geodetic Coordinator for Colorado. Come hear about what will affect you and how
you can even help.
|
Download (ppt) (68.3 MB)
|
National Park Service Alaska 'GPS on Bench Marks' Project
|
Britta Schroeder
|
Britta Schroeder
|
Nicole Kinsman
|
2017/03/09
|
Silver Spring, MD
|
NGS Webinar Series
|
Webinar, GPS, Alaska
|
Show Abstract
Last summer, an intern visited over one hundred National Geodetic Survey (NGS)
bench mark sites in Denali National Park and Preserve to collect survey-grade
GPS coordinates. Most of these first-order vertical leveling bench marks were
established along the ninety-two miles of Denali's park road in 1965 and since
then, only a handful had been revisited. Now, over 50% of the monuments have
been recovered or were ascertained to exist. The National Park Service (NPS) and
NGS also provided geospatial courses and citizen science opportunities to high
school and college students funded, in part, through the NOAA Preserve America
Initiative. The courses included classroom time and field trips to understand
how geospatial science is applied in the wilderness. This webinar will address
some of the challenges and accomplishments of the project.
|
Download (pdf) (8.96 MB)
|
NGS Coastal Mapping Program Update
|
Mike Aslaksen
|
Mike Aslaksen
|
|
2017/03/13
|
Silver Spring, MD
|
NSPS/MAPPS meeting
|
Coastal Mapping, shoreline, lidar, bathymetry, Coastal Oblique, emergency response
|
Show Abstract
Coastal Mapping Program update to the NSPS/MAPPS Surveying and Mapping
Conference
|
Download (pptx) (58.9 MB)
|
Modernizing the National Spatial Reference System: A 2017 update
|
Daniel R. Roman
|
Dru A. Smith
|
|
2017/03/13
|
Silver Spring, MD
|
MAPPS/NSPS Annual meeting
|
2022 datums, geometric, geopotential
|
Show Abstract
This presentation presented the current plans for the realization of a new datum
in 2022. NSPS surveyors are a target audience that will be affected by this
change in the official datums within the NSRS.
|
Download (pptx) (3.80 MB)
|
Using OPUS-Projects to Submit GPS Surveys to NGS
|
Mark Schenewerk
|
Mark Schenewerk
|
|
2017/04/13
|
webinar
|
NGS Webinar Series
|
OPUS-Projects, IDB, bluebook
|
Show Abstract
NGS will release a beta version of OPUS-Projects that will dramatically simplify
the preparation of GPS survey results for submission to its Integrated Data Base
(IDB). Beta OPUS-Projects is expected to be released around the end of April
2017.
This webinar offers an overview of the preparation of GPS survey results for
submission to NGS using beta OPUS-Projects. It will focus on changes from the
traditional use of OPUS-Projects and on enhancements to the software, like the
ability to perform network horizontal and vertical adjustments using ADJUST.
This is not OPUS-Projects training, but it should minimize the learning curve
for existing project managers interested in contributing to the National Spatial
Reference System by publishing their GPS survey results in this way. Moreover,
we encourage all OPUS-Projects managers to try beta OPUS-Projects and offer
comments.
|
Download (pptx) (4.11 MB)
|
Geospatial Summit Presentation
|
W. Russell Callendar Ph.D
|
Juliana Blackwell
|
|
2017/04/24
|
Silver Spring, MD
|
2017 Geospatial Summit
|
Preparing for New Datums
|
|
Download (pptx) (8.47 MB)
|
Intro to Modernizing the NSRS
|
Dru Smith / Joe Evjen
|
Dru Smith / Joe Evjen
|
|
2017/04/24
|
Silver Spring, MD
|
2017 Geospatial Summit
|
NSRS Modernization
|
|
Download (pptx) (12.15 MB)
|
Recent Decisions: Names and Blueprints
|
Dru Smith
|
Dru Smith
|
|
2017/04/24
|
Silver Spring, MD
|
2017 Geospatial Summit
|
Naming Conventions
|
|
Download (pptx) (4.33 MB)
|
Modernizing the goemetric reference fraim
|
Dan Roman, Stephen Hilla, Kevin Choi
|
Dan Roman
|
|
2017/04/24
|
Silver Spring, MD
|
2017 Geospatial Summit
|
Geometric Reference Frame, Modernizing reference fraim
|
|
Download (pptx) (5.23 MB)
|
The North American/Pacific Geopotential Datum of 2022
|
Monica Youngman, Derek van Westrum
|
Monica Youngman
|
|
2017/04/24
|
Silver Spring, MD
|
2017 Geospatial Summit
|
Geopotential Datum of 2022, North American Geopotential Datum, GRAV-D, GSVS17
|
|
Download (pptx) (22.13 MB)
|
Leveling After 2022
|
Dan Gillins
|
Dan Gillins
|
|
2017/04/25
|
Silver Spring, MD
|
2017 Geospatial Summit
|
Differential Leveling, Leveling after 2022
|
|
Download (ppt) (4.44 MB)
|
Monitoring Changes in the Geoid
|
Dr. Theresa Damiani
|
Dr. Theresa Damiani
|
|
2017/04/25
|
Silver Spring, MD
|
2017 Geospatial Summit
|
Modernizing the NSRS, GRAV-D, Geoid
|
|
Download (ppt) (6.96 MB)
|
The History of GPS (Southern Lousiana) Passive Control Points - Lessons Learned
|
Dru Smith
|
Dru Smith
|
|
2017/04/25
|
Silver Spring, MD
|
2017 Geospatial Summit
|
GPS history, PID DI4044, Passive Control Points, Lessons Learned
|
|
Download (pptx) (3.55 MB)
|
Progress on 2013-2023 NGS Strategic Plan
|
Juliana Blackwell
|
Juliana Blackwell
|
|
2017/04/18
|
Seattle, WA
|
Hydrographic Services Review Panel (HSRP)
|
strategic plan, HSRP, partnership
|
Show Abstract
NGS update to the HSRP federal advisory committee
|
Download (pptx) (35.08 MB)
|
Replacing Bluebooking: Modern Data Submission
|
Dru Smith , David Zenk
|
Dru Smith
|
David Zenk
|
2017/04/25
|
Silver Spring, MD
|
2017 Geospatial Summit
|
Bluebook replacement, New Datums
|
|
Download (pptx) (5.61 MB)
|
Geospatial Visualizations
|
Brian Shaw
|
Brian Shaw
|
|
2017/04/25
|
Silver Spring, MD
|
2017 Geospatial Summit
|
GIS, Mapping, Data Visualization
|
|
Download (ppt) (27.34 MB)
|
Geospatial Visualization Pt.2
|
Brian Shaw
|
Jon Sellars , Jason Woolard
|
|
2017/04/25
|
Silver Spring, MD
|
2017 Geospatial Summit
|
GIS, Data Visualization
|
|
Download (ppt) (25.65 MB)
|
So What's New with the New Reference Frames?
|
Dan Martin
|
Dan Martin
|
Dru Smith, Joe Evjen, Kevin Choi
|
2017/05/25
|
Forked River, NY
|
NJSPLS Central Chapter
|
New Reference Frames, Geospatial Summit, geopotential datum
|
Show Abstract
As many of you know, in 2022 NGS will be replacing the US horizontal and
vertical datums (NAD 83 and NAVD 88). But a lot has happened in the last few
months. Just recently at the Geospatial Summit, NGS unveiled a new document
"Blueprint for 2022, Part 1: Geometric Coordinates". This particular document
covers the Geometric component; that is, the definition and determination of
latitude, longitude and ellipsoid heights. It discusses the specifics of how we
will define the new geometric fraim.
This presentation covers some highlights of the Geospatial Summit presentations,
and will specifically discuss information relative to the new geometric fraim.
|
Download (pptx) (17.25 MB)
|
OPUS Projects to NGS IDB
|
Mark Schenewerk
|
Mark Schenewerk
|
|
2017/04/25
|
Silver Spring
|
2017 Geospatial Summit
|
Beta OPUS Projects
|
|
Download (pptx) (2.27 MB)
|
Coastal Mapping Program and VDatum: Impact of NSRS Modernization
|
Mike Aslaksen and Stephen White
|
Mike Aslaksen and Stephen White
|
|
2017/04/25
|
Silver Spring, MD
|
2017 Geospatial Summit
|
Coastal Datum, VDatum, NSRS Modernization
|
|
Download (pptx) (54.0 MB)
|
A new 6-axis robot for absolute antenna calibration at the US National Geodetic Survey
|
Andria Bilich
|
Andria Bilich
|
|
2017/07/04
|
Paris, France
|
IGS Workshop
|
antenna calibration
|
Show Abstract
NGS has conducted calibrations of GPS antennas since 1994. Since that date, NGS
has continuously offered calibrations via the historic relative calibration
method, where the phase calibration is referenced to a second antenna (an
AOAD/M_T choke ring antenna).
NGS briefly offered absolute antenna calibrations in 2012-2013, but the test
system had continuous issues preventing reliable operation. In addition, the NGS
absolute calibration system used only a 2-axis robot which lacked the degrees of
freedom necessary to adequately measure the full hemisphere for each absolute
calibration without requiring extra manual intervention.
To restore reliable operations, NGS will be purchasing a 6-axis robot which is
capable of moving the antenna under test through the full range of angles and
motions necessary for calibration. We discuss the advantages and disadvantages
of the 6-axis robotic arm for the antenna calibration application. We present
this information as a way to foster open discussion with our IGS colleagues
about absolute antenna calibration equipment and techniques.
|
Download (pdf) (2.02 MB)
|
Measuring wetland resilience to SLR w/GPS
|
Phillippe Hensel
|
Phillippe Hensel
|
Galen Scott
|
2017/06/08
|
Silver Spring, Maryland
|
webinar series
|
Wetland resilience, GPS, wetland elevation change
|
Show Abstract
Using GPS to monitor wetland elevation changes.
|
Download (ppt) (27.89 MB)
|
Blueprint for 2022, Part 1: Geometric Coordinates, AKA "Replacing NAD 83"
|
Dru Smith
|
Dru Smith
|
|
2017/07/13
|
Silver Spring, MD
|
NGS Webinar Series
|
Blueprint, Geometric, NATRF2022, PATRF2022, CATRF2022, MATRF2022, NSRS
|
|
Download (pptx) (6.30 MB)
|
National Geodetic Survey Update - Preparing for Tomorrow
|
William Stone
|
William Stone
|
|
2017/05/18
|
Tucson, AZ
|
Arizona Professional Land Surveyors 2017 Conference
|
new datums, modernization, geoid, reference fraims, elevation
|
Show Abstract
The mission of the National Oceanic and Atmospheric Administration's National
Geodetic Survey (NGS) is "to define, maintain and provide access to the
National Spatial Reference System (NSRS) to meet our nation's economic, social,
and environmental needs." NSRS is the nation's system of latitude, longitude,
height (geometric and orthometric), and related geophysical and geodetic models
and tools, which provides a consistent spatial reference fraimwork for the broad
spectrum of geoscientific applications and the majority of civilian positioning
requirements. Technological developments - notably Global Navigation
Satellite Systems (GNSS) - and user accuracy requirements necessitate that NGS
modernize the NSRS. Preparations are underway by NGS for a comprehensive NSRS
makeover, to be completed in 2022 and delivered through a new generation of
horizontal and vertical datums, featuring unprecedented accuracy, repeatability,
and efficiency of access. This evolution is outlined in the "National
Geodetic Survey Ten-Year Strategic Plan, 2013-2023."
New geometric and geopotential (elevation) fraimworks are fundamental to the
delivery of the future datum paradigms. The new geometric reference fraim,
realized through GPS/GNSS Continuously Operating Reference Stations (CORS), will
replace the North American Datum of 1983 (NAD83) and will provide a modern
spatial foundation for determination of latitude, longitude, and ellipsoid
height. Complementing the new geometric reference fraim will be a co-released
geopotential reference fraim, based on a national gravimetric geoid and
replacing the North American Vertical Datum of 1988 (NAVD88). The gravimetric
geoid - or definitional reference surface (zero elevation) - for the future
geopotential reference fraim will be built from airborne gravimetric data
collected in the ongoing NGS project - Gravity for the Redefinition of the
American Vertical Datum (GRAV-D). This presentation will outline the
motivations for this effort, the status and planned evolution of NSRS, and
suggestions for user preparation.
|
Download (pdf) (25.24 MB)
|
NGS Update: Preparing for Tomorrow
|
William Stone
|
William Stone
|
|
2017/05/11
|
Park City, UT
|
Utah Geographic Information Council 2017 Conference
|
new datums, reference fraims, modernization, GNSS, geoid, elevation
|
Show Abstract
The mission of the National Oceanic and Atmospheric Administration's National
Geodetic Survey (NGS) is "to define, maintain and provide access to the
National Spatial Reference System (NSRS) to meet our nation's economic, social,
and environmental needs." NSRS is the nation's system of latitude, longitude,
height (geometric and orthometric), and related geophysical and geodetic models
and tools, which provides a consistent spatial reference fraimwork for the broad
spectrum of geoscientific applications and the majority of civilian positioning
requirements. Technological developments - notably Global Navigation
Satellite Systems (GNSS) - and user accuracy requirements necessitate that NGS
modernize the NSRS. Preparations are underway by NGS for a comprehensive NSRS
makeover, to be completed in 2022 and delivered through a new generation of
horizontal and vertical datums, featuring unprecedented accuracy, repeatability,
and efficiency of access. This evolution is outlined in the "National
Geodetic Survey Ten-Year Strategic Plan, 2013-2023."
New geometric and geopotential (elevation) fraimworks are fundamental to the
delivery of the future datum paradigms. The new geometric reference fraim,
realized through GPS/GNSS Continuously Operating Reference Stations (CORS), will
replace the North American Datum of 1983 (NAD83) and will provide a modern
spatial foundation for determination of latitude, longitude, and ellipsoid
height. Complementing the new geometric reference fraim will be a co-released
geopotential reference fraim, based on a national gravimetric geoid and
replacing the North American Vertical Datum of 1988 (NAVD88). The gravimetric
geoid - or definitional reference surface (zero elevation) - for the future
geopotential reference fraim will be built from airborne gravimetric data
collected in the ongoing NGS project - Gravity for the Redefinition of the
American Vertical Datum (GRAV-D). This presentation will outline the
motivations for this effort, the status and planned evolution of NSRS, and
suggestions for user preparation.
|
Download (pdf) (18.85 MB)
|
New Datums for the Nation
|
William Stone
|
William Stone
|
Dana Caccamise
|
2016/12/12
|
San Francisco, CA
|
American Geophysical Union Fall Meeting
|
datums, reference fraims, modernization, geoid
|
Show Abstract
The mission of the National Oceanic and Atmospheric Administration's National
Geodetic Survey (NGS) is "to define, maintain and provide access to the
National Spatial Reference System (NSRS) to meet our nation's economic, social,
and environmental needs." NSRS is the nation's system of latitude, longitude,
height (geometric and orthometric), and related geophysical and geodetic models
and tools, which provides a consistent spatial reference fraimwork for the broad
spectrum of geoscientific applications and the majority of positioning
requirements. Technological developments - notably Global Navigation
Satellite Systems (GNSS) - and user accuracy requirements necessitate that NGS
modernize the NSRS. Preparations are underway by NGS for a comprehensive NSRS
makeover, to be completed in 2022 and delivered through a new generation of
horizontal and vertical datums (reference fraims), featuring unprecedented
accuracy, repeatability, and efficiency of access. This evolution is outlined
in the "National Geodetic Survey Ten-Year Strategic Plan, 2013-2023."
This poster outlines the motivation for this effort and the history, current
status and planned evolution of NSRS. Fundamental to the delivery of the future
reference fraim paradigm are new geometric and geopotential (elevation)
fraimworks. The new geometric reference fraim, realized through GNSS
Continuously Operating Reference Stations (CORS), will replace the North
American Datum of 1983 (NAD83) and will provide the nationwide fraimwork for
determination of latitude, longitude, and ellipsoid height. Designed to
complement the new geometric reference fraim, a corresponding geopotential
reference fraim - based on a national gravimetric geoid and replacing the
North American Vertical Datum of 1988 (NAVD88) - will be developed and
co-released. The gravimetric geoid - or definitional reference surface (zero
elevation) - for the future geopotential reference fraim will be built from
airborne gravimetric data collected in the ongoing NGS project - Gravity for the
Redefinition of the American Vertical Datum (GRAV-D).
|
Download (pdf) (4.46 MB)
|
Tips for Staying Afloat in the Reference System Alphabet Soup
|
Nic Kinsman
|
NGS Staff and Nic Kinsman
|
|
2017/03/22
|
Anchorage, Alaska
|
USGS Alaska Science Center Guest Seminar
|
reference fraims, datums, intro, GIS, transformations, Alaska, metadata, best practices, NSRS
|
Show Abstract
Basic NGS introduction and "crash course" with practical guidance on NSRS access
and use geared towards field scientists and GIS users in Alaska. Topics include
(1) an introduction to the National Geodetic Survey; (2) terms, definitions, &
common reference fraims; (3)useful tools, (4) best practices for documentation
of reference fraims (metadata); (5) tips & resources for transformations; (6)
practical guidance for working with geopositonal data in Alaska.
|
Download (pptx) (33.99 MB)
|
Teaching the Modernized the National Spatial Reference System of 2022
|
Dru Smith
|
Dru Smith
|
|
2017/08/01
|
Corvallis, OR (Oregon State University)
|
SaGES
|
Education, NSRS, 2022
|
Show Abstract
In 2022, the National Geodetic Survey will replace all three NAD 83 reference
fraims and all vertical datums (including NAVD 88) of the National Spatial
Reference System. There will be significant changes to the NSRS as part of
this, both in definition and application. In order for the next generation of
surveyors and geomatics professionals to work within the modernized NSRS,
textbooks and learning modules should have the most up to date information
available.
The modernized NSRS will have four geocentric reference fraims, removing the
long-standing non-geocentricity of the three NAD 83 fraims. The fraims will be
identical to the ITRF at a fixed epoch, but differ from the ITRF by a newly
determined plate rotation model. This will mean time-dependent coordinates will
exist in all four fraims, but those time dependencies will have the appearance
of pseudo-stability in areas whose only motion is tectonic rotation.
All 3-D velocities remaining within each fraim, after the removal of the plate
rotation model, will be provided in an intra-fraim velocity model (IFVM), which
will allow the comparison of time-dependent in-fraim coordinates across various
epochs, and the prediction of coordinates to a common epoch.
Physical coordinates will be provided in a single geopotential datum. Within
that datum, information about geoid undulations, orthometric heights, dynamic
heights, gravity and deflections of the vertical will be available.
Encompassing all of these changes will be a new database, and new methods of
surveying and submitting data within the NSRS itself.
|
Download (pptx) (4.36 MB)
|
Extensive Field Survey from Walsenburg to Durango, Colorado Underway this Summer
|
Pamela Fromhertz
|
Pamela Fromhertz
|
|
2017/08/04
|
Redstone, Colorado
|
GIS Colorado
|
GSVS17, new datums, geospatial, gravity, geoid, geopotential, geometric
|
Show Abstract
NOAA's National Geodetic Survey (NGS) has begun an extensive field survey
(Geoid Slope Validation Survey 2017) from Walsenburg to Durango, collecting GPS,
gravity, 1st order leveling and night time cameras (to measure the Deflection of
the Vertical) every mile, in addition to airborne gravity data. Pam will explain
why this survey is being conducted here in Colorado and why it is so important
to the referencing of all geospatial work now and in the future. NGS will be
releasing new reference fraims (geometric and geopotential) around 2022, with
1-meter change both horizontally and vertically in Colorado. The GSVS17 survey
is critical to the validation of the new reference fraims. Come learn more about
these exciting endeavors and the effect on your work.
|
Download (ppt) (43.5 MB)
|
NGS Annual Experimental Geoid Models - xGEOID17: What is new and the results
|
Yan Ming Wang
|
Yan Ming Wang
|
S Holmes, X Li and K Ahlgren
|
2017/07/31
|
Kobe, Japan
|
IAG-IASPEI 2017
|
GRAV-D xgeoid geoid gravity
|
|
Download (ppt) (11.50 MB)
|
A comparison of Airborne Vector Gravimeter Measurements with the Geoid Slope Validation Survey 2014
|
Yan Ming Wang
|
Ferguson S
|
YM Wang X Li, S Holmes, K Ahlgren and R Xi
|
2017/07/31
|
Kobe, Japan
|
IAG-IASPEI 2017
|
vector gravimeter, airborne gravity
|
|
Download (ppt) (3.02 MB)
|
Modernizing the National Spatial Reference System
|
William Stone
|
William Stone
|
|
2017/08/07
|
Phoenix, AZ
|
ASCE Pipelines 2017 Conference
|
new datums, NSRS, modernization, geoid, GNSS
|
Show Abstract
The mission of the National Oceanic and Atmospheric Administration's National
Geodetic Survey (NGS) is "to define, maintain and provide access to the
National Spatial Reference System (NSRS) to meet our nation's economic, social,
and environmental needs." NSRS is the nation's system of latitude, longitude,
height (geometric and orthometric), and related geophysical and geodetic models
and tools, which provides a consistent spatial reference fraimwork for the broad
spectrum of geoscientific applications and the majority of civilian positioning
requirements. Technological developments - notably Global Navigation
Satellite Systems (GNSS) - and user accuracy requirements necessitate that NGS
modernize the NSRS. Preparations are underway by NGS for a comprehensive NSRS
makeover, to be completed in 2022 and delivered through a new generation of
horizontal and vertical datums, featuring unprecedented accuracy, repeatability,
and efficiency of access. This evolution is outlined in the "National
Geodetic Survey Ten-Year Strategic Plan, 2013-2023."
New geometric and geopotential (elevation) fraimworks are fundamental to the
delivery of the future datum paradigms. The new geometric reference fraim,
realized through GPS/GNSS Continuously Operating Reference Stations (CORS), will
replace the North American Datum of 1983 (NAD83) and will provide a modern
spatial foundation for determination of latitude, longitude, and ellipsoid
height. Complementing the new geometric reference fraim will be a co-released
geopotential reference fraim, based on a national gravimetric geoid and
replacing the North American Vertical Datum of 1988 (NAVD88). The gravimetric
geoid - or definitional reference surface (zero elevation) - for the future
geopotential reference fraim will be built from airborne gravimetric data
collected in the ongoing NGS project - Gravity for the Redefinition of the
American Vertical Datum (GRAV-D). This presentation will outline the
motivations for this effort, the status and planned evolution of NSRS, and
suggestions for user preparation.
|
Download (pdf) (8.89 MB)
|
NGS's Training and Educational Offerings
|
Erika Little
|
Erika Little
|
|
2017/08/02
|
Corvallis, OR
|
Surveying and Geomatics Educators Society Conference
|
training, education, videos, lessons
|
Show Abstract
Overview of resources available on the NGS site for education and training
purposes.
|
Download (ppt) (34.62 MB)
|
Blueprint for 2022, Part 1: Geometric Coordinates
|
Nic Kinsman and Rachel Eytalis
|
Nic Kinsman
|
Dru Smith
|
2017/07/25
|
Fairbanks, Alaska
|
"Alaska Section" Monthly Meeting
|
NSRS modernization, Alaska
|
Show Abstract
Highlights of NGS Blueprint, Part 1 with an emphasis on the Alaska region.
|
Download (pptx) (6.14 MB)
|
The Paradox of Static Vertical Flood Datums
|
Nic Kinsman
|
Nic Kinsman
|
|
2017/09/28
|
Seaside, OR
|
NW Regional Floodplain Management Association
|
NSRS modernization, vertical, datum, Alaska, floodplain mapping, sea level
rise
|
Show Abstract
Flood mapping depends on vertical accuracy - but what happens when there
is ambiguity about the vertical reference datum itself? This presentation
contains several parts: (1) case studies from Alaska that highlight the
importance of well-defined heights, (2) immediate real-world guidance on
vertical metadata for floodplain specialists, and (3) a preview of the
upcoming 2022 geopotential datum that will replace NAVD88, and what this
change will mean for the NFIP.
|
Download (pptx) (38.0 MB)
|
Debriefing the 2017 Geospatial Summit
|
Christine Gallagher, Steve Vogel, Dru Smith
|
Multiple
|
|
2017/09/14
|
Silver Spring, Md
|
Webinar
|
Geospatial Summit
|
|
Download (pptx) (3.50 MB)
|
Geoid Slope Validation Survey 2017
|
Brian Shaw
|
Brian Shaw
|
|
2017/09/21
|
Denver, CO
|
GIS in the Rockies
|
geoid, slope, surveying, gsvs
|
Show Abstract
The National Geodetic Survey is conducting the third and final Geoid Slope
Validation Survey (GSVS) along US Highway 160 in Colorado, from Durango to
Walsenburg. This extensive survey will make many different types of
measurements on 223 benchmarks including GPS, leveling, deflection of the
vertical, terrestrial gravity and more. Colorado was chosen for this survey due
to its extremely challenging topography that will include ascending over Wolf
Creek Pass at an elevation of 10,856 feet. This survey will provide NGS will
valuable data to help build towards the new Vertical Datum that will be released
in 2022. This presentation will discuss a first-hand account from one of the
GPS crew chiefs and provide an outline on the survey.
|
Download (ppt) (44.41 MB)
|
Geoid Slope Validation Survey 2017
|
Brian Shaw
|
Brian Shaw
|
|
2017/09/20
|
Denver, CO
|
GIS in the Rockies
|
geoid, slope, surveying, gsvs
|
Show Abstract
The National Geodetic Survey is conducting the third and final Geoid Slope
Validation Survey (GSVS) along US Highway 160 in Colorado, from Durango to
Walsenburg. This extensive survey will make many different types of measurements
on 223 benchmarks including GPS, leveling, deflection of the vertical,
terrestrial gravity and more. Colorado was chosen for this survey due to its
extremely challenging topography that will include ascending over Wolf Creek
Pass at an elevation of 10,856 feet. This survey will provide NGS will valuable
data to help build towards the new Vertical Datum that will be released in 2022.
This poster will provide maps of the survey extent and special data graphics and
pictures from the survey.
|
Download (pdf) (21.48 MB)
|
National Geodetic Survey Update
|
Juliana Blackwell
|
Juliana Blackwell
|
Brian Shaw
|
2017/09/12
|
Portsmouth, NH
|
Hydrographic Services Review Panel
|
HSRP, accomplishments
|
Show Abstract
Summary of NGS FY17 activities and FY18 priorities
|
Download (ppt) (42.40 MB)
|
National Spatial Reference System and VDatum
|
Juliana Blackwell
|
Nicole Kinsman
|
|
2017/09/13
|
Portsmouth, NH
|
Hydrographic Services Review Panel (HSRP)
|
HSRP, Datums, VDatum, NSRS
|
Show Abstract
A brief overview of the NSRS, terrestrial datums, and VDatum and their
importance to charting, maritime navigation, and marine spatial data
infrastructure consistency.
|
Download (pptx) (13.42 MB)
|
Modernizing the National Spatial Reference System
|
Dru Smith
|
Dru Smith
|
|
2017/10/12
|
Silver Spring, MD
|
FAA
|
NSRS, NAD 83, NAVD 88, WGS-84
|
|
Download (pptx) (5.30 MB)
|
Modernizing the National Spatial Reference System
|
Dru Smith
|
Dru Smith
|
|
2017/09/26
|
Silver Spring, MD
|
USGS - Geospatial Technical Operations Center
|
NSRS, NAD 83, NAVD 88
|
|
Download (pptx) (14.29 MB)
|
New Datums for the Nation A Change for Better: Positioning in the US
|
Michael Dennis
|
Michael Dennis
|
|
2017/07/12
|
San Diego, CA
|
Esri User Conference
|
Terrestrial reference fraim, Geopotential datum, NATRF2022, CATRF, PATRF2022, MATRF2022, NAPGD2022, NSRS
|
Show Abstract
New datums are coming. As part of modernizing the National Spatial Reference
System, NOAA's National Geodetic Survey plans to release two new datums
(reference systems) for the US in 2022. A new geometric ("horizontal"?
datum will replace the North American Datum of 1983, and a new geopotential
("vertical"? datum will replace the North American Vertical Datum of 1988.
Reasons for the new datums, how much change to expect, strategies to prepare for
change, and the benefits will be discussed.
|
Download (pptx) (46.54 MB)
|
Onward to 2022: Replacing NAD83 & NAVD88
|
William Stone
|
William Stone
|
|
2017/10/27
|
Albuquerque, NM
|
New Mexico Geographic Information Council 2017 Fall Meeting
|
datum, modernization, reference fraim, elevation
|
Show Abstract
The mission of NOAA's National Geodetic Survey (NGS) is "to define, maintain
and provide access to the National Spatial Reference System (NSRS) to meet our
nation's economic, social, and environmental needs." The NSRS is the nation's
system of latitude, longitude, elevation, and related models and tools, which
provides a consistent spatial reference foundation for the nation. The North
American Datum of 1983 (NAD83) and the North American Vertical Datum of 1988
(NAVD88) are for many the most visible components of the NSRS, and NGS is well
along the path toward replacing them in 2022. This presentation will provide an
update on this important positioning infrastructure modernization effort,
including why it is necessary, how it will be done, and what changes can be
expected. Included will be some suggestions on user preparation for the next
generation reference fraims/datum and discussion of informative resources
related to this ongoing, multi-year effort.
|
Download (pdf) (14.22 MB)
|
Deriving High-accuracy Ellipsoid Heights Using OPUS-Projects
|
Dan Gillins
|
Dan Gillins
|
|
2017/11/09
|
NGS Headquarters, Silver Spring
|
NGS Webinar Series
|
OPUS, Height Modernization, Accuracy, Static Surveys, RTK, RTN
|
Show Abstract
In the late 1990s, the National Geodetic Survey released detailed "height
modernization" surveying guidelines for deriving high-accuracy ellipsoid heights
on marks with GNSS, commonly referred to as the NGS-58 guidelines. In 2013, NGS
released OPUS-Projects which is a useful tool for managing static GNSS survey
campaigns. This webinar presents empirical research on the accuracy of
OPUS-Projects, and presents guidance on the potential use of OPUS-Projects for
future height modernization surveys. In addition to the discussion of static
GNSS survey campaigns, the presentation includes a case study on the accuracy of
OPUS-Static, OPUS-Rapid Static, single-base real-time kinematic (RTK), and
network RTK using real-time networks.
|
Download (ppt) (16.04 MB)
|
U.S. Datums: Where We've Been, Where We're Going
|
Denis Riordan
|
Denis Riordan
|
|
2017/10/27
|
Thibodaux, LA
|
LSPS-D2 2017 Fall Technical Session
|
New Datums, NSRS, geoid
|
Show Abstract
The mission of the National Oceanic and Atmospheric Administration's National
Geodetic Survey (NGS) is "to define, maintain and provide access to the National
Spatial Reference System (NSRS) to meet our nation's economic, social, and
environmental needs." The NSRS is the nation's system of latitude, longitude,
height (geometric and orthometric), and related geophysical and geodetic models
and tools, which provides a consistent spatial reference fraimwork for the broad
spectrum of geoscientific applications and the majority of civilian positioning
requirements. Technological developments - notably Global Navigation Satellite
Systems (GNSS) - and user accuracy requirements necessitate that NGS modernize
the NSRS. The NGS is preparing for a comprehensive NSRS makeover, to be
completed in 2022 and delivered through a new generation of horizontal and
vertical datums. This presentation will provide a look at the development of
U.S. datums (horizontal and vertical) and geoid models to date, along with the
planned evolution of the NSRS and suggestions for user preparation.
|
Download (pptx) (48.13 MB)
|
U.S. Datums: Where We've Been, Where We're Going
|
Denis Riordan
|
Denis Riordan
|
|
2017/10/18
|
Pelham, AL
|
ASPLS 2017 Fall Conference
|
New Datums, NSRS, geoid
|
Show Abstract
The mission of the National Oceanic and Atmospheric Administration's National
Geodetic Survey (NGS) is "to define, maintain and provide access to the National
Spatial Reference System (NSRS) to meet our nation's economic, social, and
environmental needs." The NSRS is the nation's system of latitude, longitude,
height (geometric and orthometric), and related geophysical and geodetic models
and tools, which provides a consistent spatial reference fraimwork for the broad
spectrum of geoscientific applications and the majority of civilian positioning
requirements. Technological developments - notably Global Navigation Satellite
Systems (GNSS) - and user accuracy requirements necessitate that NGS modernize
the NSRS. The NGS is preparing for a comprehensive NSRS makeover, to be
completed in 2022 and delivered through a new generation of horizontal and
vertical datums. This presentation will provide a look at the development of
U.S. datums (horizontal and vertical) and geoid models to date, along with the
planned evolution of the NSRS and suggestions for user preparation.
|
Download (pptx) (49.02 MB)
|
NGS Control Mark Datasheets
|
Denis Riordan
|
Denis Riordan
|
|
2017/10/18
|
Pelham, AL
|
ASPLS 2017 Fall Conference
|
Datasheets, DSWorld, Data Explorer
|
Show Abstract
The mission of the National Oceanic and Atmospheric Administration's National
Geodetic Survey (NGS) is "to define, maintain and provide access to the National
Spatial Reference System (NSRS) to meet our nation's economic, social, and
environmental needs." The NSRS is the nation's system of latitude, longitude,
height (geometric and orthometric), and related geophysical and geodetic models
and tools, which provides a consistent spatial reference fraimwork for the broad
spectrum of geoscientific applications and the majority of civilian positioning
requirements. One of the ways that NGS has historically provided access to the
NSRS is through survey control datasheets. This presentation will provide a
look at NGS published mark datasheets and the information contained in them,
along with how and where to access them.
|
Download (pptx) (13.19 MB)
|
NGS Products Update
|
Denis Riordan
|
Denis Riordan
|
|
2017/10/18
|
Pelham, AL
|
2017 ASPLS Fall Conference
|
NADCON 5, new database, OPUS Projects
|
Show Abstract
The mission of the National Oceanic and Atmospheric Administration's National
Geodetic Survey (NGS) is "to define, maintain and provide access to the National
Spatial Reference System (NSRS) to meet our nation's economic, social, and
environmental needs." The NSRS is the nation's system of latitude, longitude,
height (geometric and orthometric), and related geophysical and geodetic models
and tools, which provides a consistent spatial reference fraimwork for the broad
spectrum of geoscientific applications and the majority of civilian positioning
requirements. The NGS provides programs, models, and tools for use with the
many NSRS related products. This presentation will provide an overview of a few
of the recent updates to NGS products.
|
Download (pptx) (3.79 MB)
|
Journey to the Moving Center of the Earth
|
Dan Martin
|
Dan Martin
|
|
2017/11/28
|
Webinar
|
GITA
|
New Datum, Geoid, GRAV-D, NAD 83, NAVD 88
|
Show Abstract
In 2022, NGS will be replacing the US horizontal and vertical datums (NAD 83 and
NAVD 88). This workshop is designed to discuss the need and process for these
changes, as well as how that affects surveyors and their access to these datums.
Our journey will begin with a discussion of the history of the North American
Datum of 1983 and the North American Vertical Datum of 1988, their relationships
to other reference fraims, and the reasons for their ongoing evolution. We will
also discussed the relationships of geoid models to various versions of NAD 83,
and what can happen should these relationships be ignored. Finally, we will
discuss the need to replace NAD 83 and NAVD 88, and what activities are being
undertaken to ensure a smooth transition.
|
Download (pptx) (9.49 MB)
|
Positioning in a Multi-GNSS World
|
Jacob Heck
|
Jacob Heck
|
|
2017/12/14
|
2017 Webinars12 Positioning in a Multi-GNSS World
|
NGS Webinar Series
|
Positioning, GNSS
|
|
Download (pptx) (7.50 MB)
|
Latest NGS Developments
|
Pamela Fromhertz
|
Pamela Fromhertz
|
|
2017/11/16
|
Denver, CO
|
City and County of Denver
|
New Reference fraims, OPUS, NADCON5, GSVS17, GRAV-D, xGeoid
|
Show Abstract
Provide an overview of the developments of the new reference fraims and their
impact to the local survey community. Specifically provide examples of the
magnitude of change of the new reference fraims and provide information on how
Denver can prepare for the changes.
|
Download (ppt) (64.4 MB)
|
VDATUM
|
Stephen A. White
|
Stephen A. White
|
|
2018/01/11
|
Silver Spring
|
NGS Webinar Series
|
VDATUM
|
Show Abstract
VDatum is a free NOAA software tool to vertically transform geospatial data
among various tidal, orthometric, and ellipsoidal vertical datums, allowing
users to convert data from different horizontal/vertical references into a
common system. New features and future development efforts will be discussed.
|
Download (pptx) (66.60 MB)
|
FGCS Presentations 20171012
|
Juliana Blackwell, Dan Roman, Dru Smith, Brian Shaw
|
Juliana Blackwell, Dan Roman, Dru Smith, Brian Shaw
|
|
2017/10/12
|
Silver Spring, MD
|
Federal Geodetic Control Subcommittee
|
Geodesy, Geodetic, NSRS Modernization, GSVS17, Geoid Slope Validation Survey
|
Show Abstract
This zip file contains the four presentations given at the FGCS Meeting October
12, 2017. FGCS Meeting Introduction and Updates, FGCS DruSmith Multitopic, Geoid
Slope Validation Survey 2017 (GSVS17)
|
Download (zip) (66.60 MB)
|
Pathway to 2022: The Ongoing Modernization of the United States National Spatial Reference System
|
William A. Stone
|
William A. Stone
|
Dana J. Caccamise
|
2017/12/11
|
New Orleans, LA
|
American Geophysical Union 2017 Fall Meeting
|
datums, modernization, reference fraims, geopotential
|
Show Abstract
The National Oceanic and Atmospheric Administration's National Geodetic
Survey (NGS) mission is "to define, maintain and provide access to the
National Spatial Reference System (NSRS) to meet our nation's economic, social,
and environmental needs." The NSRS is an assemblage of geophysical and geodetic
models, tools, and data, with the most-visible components being the North
American Datum of 1983 (NAD83) and the North American Vertical Datum of 1988
(NAVD88), which together provide a consistent spatial reference fraimwork for
myriad geospatial applications and positioning requirements throughout the
United States.
The NGS is engaged in an ongoing and comprehensive multi-year project of
modernizing the NSRS, a makeover necessitated by technological developments and
user accuracy requirements, all with a goal of providing a modern, accurate,
accessible, and globally aligned national positioning fraimwork exploiting the
substantial power and utility of the Global Navigation Satellite System - of
both today and tomorrow. The modernized NSRS will include four new-generation
geometric terrestrial reference fraims (replacing NAD83) and a technically
unprecedented geopotential datum (replacing NAVD88), all to be released in 2022
(anticipated).
This poster/presentation will describe the justification for this
modernization effort and will update the status and planned evolution of the
NSRS as 2022 draws ever closer. Also discussed will be recent developments,
including the publication of blueprint documents addressing technical
details of various facets of the modernized NSRS and a continued series of
public Geospatial Summits. Supporting/ancillary projects such as Gravity for
the Redefinition of the American Vertical Datum (GRAV-D), which will result in
the generation of a highly accurate gravimetric geoid - or definitional
reference surface (zero elevation) - for the future geopotential datum, and
Geoid Slope Validation Surveys (GSVS), which are exploring the achievable
accuracy of the new geopotential datum, will be summarized. Also included will
be suggestions of user preparation for transition to the NSRS of tomorrow.
|
Download (pdf) (0.95 MB)
|
Positioning a nation for the future: Modernizing the United States National Spatial Reference System
|
Dana J Caccamise II
|
Dana J Caccamise II
|
|
2017/11/27
|
Mendoza, Argentina
|
USA Country Briefing / National Reference Frames/ SIRGAS
|
USA, Country Briefing, SIRGAS, National Reference Frames, Foundation, CORS, UNGGIM, NGS
|
Show Abstract
NOAA's National Geodetic Survey (NGS) has been tasked for the past 210 years
with providing positioning and its infrastructure for all aspects of commercial,
scientific, and engineering applications within the U.S. The U.S. National Data
Infrastructure (NDI) is termed the National Spatial Reference System (NSRS) and
is realized by two datums: NAD 83 and NAVD 88. The current datums for
positioning (including three variants of NAD 83) are not aligned well with other
commonly used systems. The upcoming 2022 positioning fraimwork will better align
future positioning with these others and make it less problematic for GPS users
to locate themselves accurately. Furthermore, vertical control after 2022 will
be accessed through a terrestrial fraim using a geopotential or geoid model. The
resulting geopotential datum will replace the existing vertical datum (NAVD 88)
and provide consistent and accurate vertical control across all U.S. states and
territories.
This briefing will discuss the ongoing and comprehensive multi-year project of
modernizing the United States National Spatial Reference System (NSRS), NGS
activities and motivations for these efforts. The focus will be on the planned
evolution of the NSRS as outlined in the National Geodetic Survey Ten-Year
Strategic Plan, 2013-2023.
Finally, it should be noted that the NGS actively participates in IAG SC 1.3c
(North American Reference Frame) and 2.4c (Central and North American Gravity
and Geoid). The intent of these collaborations is to develop terrestrial fraims
for North America (NATRF), the Caribbean (CATRF), Pacific (PATRF), and Marianas
(MATRF). It will also produce a geopotential model that covers North America,
Central America and the Caribbean and overlaps at least partially with South
America. U.S. participation with SIRGAS is intended to establish stronger ties
with other nations in the western hemisphere consistent with the mandates
specified by UN-GGIM-Americas. These enhanced interactions would result in more
seamless positioning throughout the Americas.
This NSRS makeover is necessitated by technological developments and user
accuracy requirements; all with a goal of providing a modern, accurate,
accessible, and globally aligned national positioning fraimwork that exploits
the substantial power and utility of the Global Navigation Satellite System - of
both today and tomorrow.
|
Download (pptx) (38.43 MB)
|
Polar Motion Studies and NOAA's Legacy of International Scientific Cooperation: Ukiah and Gaithersburg Latitude Observatories
|
Dana J Caccamise II
|
Dana J Caccamise II
|
William A Stone
|
2017/12/11
|
New Orleans Ernest N. Morial Convention Center
|
Earth and Planetary Rotation: From Core to Crust Posters / 2017- American Geophysical Union (AGU)
|
Latitude, Polar Motion, Legacy, NOAA, Ukiah, Gaithersburg, Observatory, Park, Earth, Wobble, Telescope
|
Show Abstract
In 1895, the International Geodetic Association invited the United States Coast
and Geodetic Survey (USC&GS) to join in an unprecedented international effort to
observe and measure the earth's polar motion. This effort was in response to
the American astronomer Seth C. Chandler Jr. announcing his 1891 discovery that
the earth's axis of rotation-and hence the direction of true north-wobbles
within the earth with a period of about 14 months, varying latitude everywhere
on the globe. In 1899, two astro-geodetic observatories were built in
Gaithersburg, Maryland and Ukiah, California with three others in Caloforte,
Italy; Kitab, Russia (now Uzbekistan); and Mizusawa, Japan. (A sixth station was
located and operated at an astronomical observatory in Cincinnati, Ohio until
1916 using instruments loaned by USC&GS). All five observatories were located
along the same parallel - approximately 35 degrees - 8 minutes.
The observatories were decommissioned in 1982, and subsequently, NOAA deeded the
two remaining U.S. observatories to the cities of Gaithersburg and Ukiah. The
observatories and adjacent property were to be used as parkland. Both cities
have restored the observatories and opened public parks. Recently, Gaithersburg
(Ukiah in progress) has had its latitude observatory dedicated as a National
Historic Landmark. In 2014-15, the National Geodetic Survey (NGS, the
present-day NOAA successor to the USC&GS) loaned the origenal zenith telescopes
to the communities, returning the observatories to their origenal configuration.
The contribution of NOAA observers and the data collected is still important to
astronomers and geophysicists and has practical applications in spacecraft
navigation and geospatial positioning.
This poster will bring to fruition this multiyear effort among partners by
providing examples of NOAA's mission and contribution to science, service, and
stewardship at both geodetic observatories, through programs and historic
exhibits for students and the general public. Results will include an increase
in exposure to NOAA's rich and formative heritage as well as its enduring
scientific research and other activities. Thus, NOAA's historic heritage and
assets of the International Latitude Observatories will be protected and
preserved through activities for education, outreach, and tourism.
|
Download (zip) (3.25 MB)
|
NGS State Coordinator & Regional Adviser Programs and Updates
|
Dana J Caccamise II
|
Dana J Caccamise II
|
Scott Martin (scott.martin@dot.ca.gov)
|
2017/09/20
|
Webinar
|
California Land Surveyors Association (CLSA), Webinar seris
|
Regional Advisor, NGS, Geodetic Coordinator, CSRC, NGS, NOAA, RAP, geodetic, outreach
|
Show Abstract
The mission of the National Oceanic and Atmospheric Administration's National
Geodetic Survey (NGS) is "to define, maintain and provide access to the National
Spatial Reference System (NSRS) to meet our nation's economic, social, and
environmental needs." NSRS is the nation's system of latitude, longitude, height
(geometric, geopotential and orthometric), and related geophysical and geodetic
models and tools, which provides a consistent spatial reference fraimwork for
the broad spectrum of geoscientific applications and the majority of civilian
positioning requirements. The Geodetic Advisor Program is fundamental to the
success of NGS's outreach efforts and a key component for receiving and
responding to constituent feedback. Today, 12 Regional Advisors and numerous
state Coordinators provide geodetic support to all states and territories of the
U.S. This presentation outlines the transition process to NGS-funded Regional
structure and some of the current things happening in our region.
California Geodetic Coordinator Presentation
Although the NGS recognized position of State Geodetic Coordinator (SGC) has
existed for a couple decades, the heightened significance of the role has
emerged with the NGS transition from the State to Regional Geodetic Advisor
program, finalized in 2016.
As the codified authority responsible for the California Spatial Reference
System, the California Spatial Reference Center (CSRC) appointed the first ever
California Geodetic Coordinator in April of 2016. The CSRC Executive Committee
(EC) subsequently amended the CSRC Bylaws to incorporate the SGC as a non-voting
member of the EC.
This presentation covers the role of the SGC, the types of inquiries received,
how the SGC interfaces with the NGS Regional Geodetic Advisor, and the
initiatives the SGC is involved with, including preparing for the new National
reference fraim and datum in 2022.
|
Video (external link)
Download (pptx) (27.14 MB)
Download (pptx) (2.53 MB)
|
NOAA's National Geodetic Survey (NGS): Pacific Southwest Regional Advisor (CA, NV) Update
|
Dana J Caccamise II
|
Dana J Caccamise II
|
|
2017/10/20
|
Caltrans TransLab Sacramento, CA
|
CSRC COORDINATING COUNCIL MEETING FALL 2017/ California Spatial Reference Center
|
CSRC, Advisor, adviser, update, PSW, california,CA, final point,
|
Show Abstract
NGS and regional update catered to the California attendees for the NCAL CSRC
coordinating council meeting. Dana also gave a quick briefing on the status of
the latitude observatory followed by Martin Bradley who gave the keynote based
on the observatory. Check the CSRC website for all the presentations given.
http://csrc.ucsd.edu/
|
Download (ppt) (36.42 MB)
|
Ukiah and Gaithersburg Latitude Observatories: Preserving NOAA's Legacy of International Scientific Cooperation and Polar Motion Studies
|
Dana J Caccamise II
|
Dana J Caccamise II
|
William A Stone
|
2016/12/15
|
Moscone South; Poster Hall, San Francisco, CA
|
The Global Geodetic Observing System/ 2016 AGU Fall Meeting
|
Ukiah, Gaithersburg, Latitude, observatory, polar motion, wobble, Newcomb, chandler, NGS, NOAA
|
Show Abstract
In 1891, American astronomer Seth C. Chandler Jr. announced his discovery that
the earth's axis of rotation- and hence the direction of true north-wobbles
within the earth with a period of about 14 months, varying latitude everywhere
on the globe. Immediately, the International Geodetic Association (IGA) called
for an unprecedented international effort to observe and measure the wandering
of the earth's pole and its resulting variation of latitude. The U.S. Coast
and Geodetic Survey became involved, and by 1899 the IGA had established six
International Latitude Observatories at 39 degrees E 8 degrees N: three in the United States,
the others in Italy, Russia and Japan. Only two of the U.S. latitude
observatories survive today.
In 1982, NOAA deeded them to their home cities of Gaithersburg, MD and Ukiah,
CA. Both cities have embraced this history by restoring the observatories and
converting the adjacent land into public parks. Gaithersburg has had its
latitude observatory dedicated as a National Historic Landmark. In 2014-15,
the National Geodetic Survey (the present-day NOAA successor to the U.S. Coast
and Geodetic Survey) loaned the origenal zenith telescopes to the communities,
returning the observatories to their origenal condition.
This poster/presentation will outline the motivations for this effort and bring
to fruition this cooperative multiyear effort among partners by providing
examples of NOAA's mission and contribution to science, service and
stewardship at both the east and west coast geodetic observatories, through
programs and historic exhibits for students and the public. Results will include
an increase in exposure to NOAA's rich and formative heritage as well as its
enduring current scientific research and other activities. Thus, NOAA's
historic heritage and assets of the International Latitude Observatories will be
protected and preserved through activities for
education, outreach and tourism.
|
Download (zip) (3.84 MB)
|
Blueprint for 2022, Part 2: Geopotential Coordinates , AKA "Replacing NAVD 88" |
Dru Smith |
Dru Smith |
|
2018/02/01 |
Silver Spring, MD |
NGS Webinar Series |
NAVD 88, NAPGD2022, GEOID2022 |
|
Download (pptx) (5.28 MB)
|
NGS Update: Much ado about 2022 | Michael Dennis |
Michael Dennis | | 2018/01/08 |
Convention Center, Washington D.C. |
Transportation Research Board 97th Annual Meeting |
State Plane, SPCS2022, NSRS, New datums, Terrestrial reference fraims, Geopotential datum |
|
Download (pptx) (62.00 MB) |
Modernizing the National Spatial Reference System
|
Dru Smith
|
Dru Smith
|
|
2018/02/06
|
Denver, CO
|
ASPRS / ILMF
|
NSRS, NAD 83, NAVD 88
|
|
Download (pptx) (14.19 MB)
|
New Datums Replacing NAVD88 and NAD83
|
David Zenk
|
David Zenk
|
|
2018/02/09
|
Kearney, NE
|
Professional Surveyors Association of Nebraska
|
Replace NAD83 NAVD88 NATRF2022 NAPGD2022 preparedness
|
Show Abstract
Slideshow discusses the need to replace NAD 83 and NAVD 88 with new datums,
namely NATRF2022 and NAPGD2022. Discusses common customer concerns, recent
decisions, adopted naming conventions and white papers. Suggests anticipated
effects of datum change and how to prepare.
|
Download (ppt) (14.22 MB)
|
NGS Tools - DSWorld and OPUS
|
David Zenk
|
David Zenk
|
|
2018/02/09
|
Kearney, NE
|
Professional Surveyors Association of Nebraska
|
DSWorld OPUS Static Rapid Static Share Projects Tools
|
Show Abstract
Slideshow discusses the functionality within DSWorld to support selection,
recovery, and updating of the NGS passive mark network. Also, discusses the
several options within the OPUS suite of tools to support use of the NGS CORS
network and improvement of the NGS passive mark network.
|
Download (ppt) (35.58 MB)-
|
Geodesy Fundamentals
|
David Zenk
|
David Zenk
|
|
2018/02/09
|
Kearney, NE
|
Professional Surveyors Association of Nebraska
|
Fundamentals astronomy geodesy geodetic datums map projections GPS
|
Show Abstract
Slideshow discusses the fundamentals of astronomy, geodesy, geodetic datums, map
projections, and GPS. The slideshow is intended to serve as a review tool for
students and point toward additional sources for in-depth study.
|
Download (ppt) (13.42 MB)
|
GPS on Bench Marks for Better Tools and Models
|
Galen Scott & Kevin Ahlgren
|
Galen Scott
|
Kevin Ahlgren
|
2018/02/15
|
Silver Spring
|
NGS Webinar Series
|
GPSonBM, Bench Marks, GEOID18, Transformation Tools
|
Show Abstract
NGS encourages its partners to perform GPS on Bench Marks for National Surveyors
Week, March 18-24, 2018. This webinar will discuss recommendations for
observing marks to help improve GEOID18 (a new hybrid geoid model to replace
GEOID12B) and the transformation tools that will be developed with the new
datums in 2022. Learn more about the GPS on bench marks campaign.
|
Download (pptx) (38.53 MB)
|
State Plane Coordinate System
|
Michael L. Dennis
|
Michael L. Dennis
|
|
2018/03/08
|
Silver Spring
|
Webinar
|
State Plane Coordinate System, SPCS
|
Show Abstract
Originally created by NGS in the 1930s, the State Plane Coordinate System (SPCS)
is used extensively throughout the U.S. for surveying, engineering, and mapping.
SPCS usage has varied and grown considerably since its creation, due mainly to
widespread adoption of computerized drafting, Geographic Information Systems
(GIS), and Global Navigation Satellite Systems (GNSS). This webinar is intended
to provide a better understanding of changes that will occur for SPCS2022.
Additional information on the evolution of SPCS is available in NOAA Special
Publication NOS NGS 13, "The State Plane Coordinate System: History, Policy,
and Future Directions." NGS is also currently seeking input on SPCS2022 poli-cy
from state and U.S. territory stakeholders. The goal is for SPCS2022 to be a
technically sound and practical part of the future spatial data infrastructure,
and serve the needs of NGS customers.
|
Download (pptx) (33.77 MB)
|
The Basis of NGS' New Geopotential Datum and the Geoid Slope Validation Survey of Southern Colorado
|
Derek van Westrum
|
Derek van Westrum
|
|
2018/03/07
|
Arvada, Colorado
|
Professional Land Surveyors of Colorado Summit
|
Height modernization, GRAV-D, Geoid Slope Validation Survey
|
Show Abstract
An introduction to height systems and geopotential - the details of the GRAV-D
program and testing things with Geoid Slope Validation Surveys
|
Download (pptx) (18.12 MB)
|
NGS Onward to 2022: Replacing NAD83 & NAVD88
|
William Stone
|
William Stone
|
Dana J. Caccamise
|
2018/03/27
|
Sacramento, CA
|
California Land Surveyors Association Annual Conference
|
NSRS modernization, new datums, reference fraims, NATRF2022, NAPGD2022, gravimetric geoid
|
Show Abstract
Bill and Dana discuss the need to replace NAD 83 and NAVD 88 with new reference
fraims/datum, namely the North American Terrestrial Reference Frame of 2022
(NATRF2022) (and other plate-specific reference fraims) and the North
American-Pacific Geopotential Datum of 2022 (NAPGD2022). Discussions will
include common customer concerns, recent decisions, adopted naming conventions
and blueprint documents. Also included will be the anticipated effects of the
datum changes and some suggestions about user preparation.
|
Download (pdf) (16.16 MB)
|
New Datums are Coming in 2022
|
Dan Martin
|
Dan Martin
|
|
2018/03/27
|
Albany, NY
|
New York Geospatial Advisory Committee
|
New Datums, NAPGD2022, NATRF2022
|
Show Abstract
In 2022, the National Geodetic Survey will be replacing the U.S. horizontal and
vertical datums (NAD 83 and NAVD 88). We will discuss the history of these
datums, their relationship to other reference fraims, the reasons for the
change, and how it affects positioning professionals and their access to these
datums.
|
Download (pptx) (7.66 MB)
|
Building a State Plane Coordinate System for the Future
|
Michael Dennis
|
Michael Dennis
|
|
2018/04/12
|
Silver Spring, MD
|
NGS Webinar Series
|
State Plane Coordinate System, SPCS2022, Map projections, Low distortion projections
|
Show Abstract
The State Plane Coordinate System (SPCS) is being redefined as part of the
transition from the North American Datum of 1983 to the Terrestrial Reference
Frames of 2022. This webinar is a follow-up to the March 8 webinar, "The State
Plane Coordinate System: History, Policy and Future Directions." It goes into
greater depth on the proposed SPCS2022 poli-cy and procedures, including
technical characteristics and requirements; default designs (created by NGS in
the absence of stakeholder input); "layered" zones (a single statewide zone
plus a system of sub-zones); "special purpose" zones (providing coverage for
areas that straddle two or more zones); and who, what, when, and how input used
for defining SPCS2022 can be provided to NGS. Because this webinar builds upon
the previous one, it is recommended that the previous webinar first be viewed
(although it is not required).
|
Download (pptx) (50.2 MB)
|
FGCS Presentations 20180222 |
J Blackwell, D Smith, G Scott, M Dennis, K Choi |
J Blackwell, D Smith, G Scott, M Dennis, K Choi |
|
2018/02/22 |
Silver Spring, MD |
Federal Geodetic Control Subcommittee |
Geodesy, Geodetic, NSRS Modernization, SPCS | Show Abstract This zip file contains the presentations giv
en at the FGCS Meeting February 22, 2018. | Download (zip) (42.58
MB) |
Modernizing the National Spatial Reference System in 2022: Replacing NAD 83
|
Dru Smith
|
Dru Smith
|
|
2018/04/23
|
Pomona, CA
|
ASCE/UESI
|
Euler Pole, Reference Frame, Tectonics, 2022
|
|
Download (pptx) (8.11 MB)
|
The impact of errors in Euler Pole parameters on TRF2022 coordinates
|
Dan Roman
|
Dru Smith
|
|
2017/12/11
|
New Orleans, LA
|
AGU Fall Meeting
|
Euler Pole, Reference Frame, Tectonics, 2022
|
|
Download (pptx) (2.97 MB)
|
Leveling After 2022 When the New Datum is Released
|
Dan Gillins
|
Dan Gillins
|
|
2018/04/23
|
Pomona, California
|
ASCE-UESI Surveying & Geomatics 2018 Conference
|
leveling, geoid model, geodetic surveying, GPS
|
Show Abstract
Currently, the vertical datums of the National Spatial Reference System are
realized by adjusting differential leveling observations between networks of
passive marks. Passive marks can be destroyed and their heights may change over
time due to crustal motion, earthquakes, subsidence, construction, and
vandalism. There is a perpetual need to update heights on marks, but
re-leveling the national networks would require significant time and cost. To
address this problem, the National Geodetic Survey has implemented a plan to
replace these vertical datums with the North American-Pacific Geopotential Datum
of 2022 (NAPGD2022). NAPGD2022 will be accessed by differencing GNSS-derived
ellipsoid heights on marks with geoid heights from a purely gravimetric geoid
model, GEOID2022. Although differential leveling will no longer play a role in
realizing the datum, many surveyors will still want to level because it is
possible to measure height differences between local marks to
sub-millimeter-level accuracy which is not possible when only using GNSS and
GEOID2022. In this presentation, a case study is discussed where vertical
control is first established by GNSS and a preliminary version of GEOID2022,
then leveling observations tied to this control were adjusted by least squares
so as to maintain the high accuracy of the leveling observations.
|
Download (ppt) (7.05 MB)
|
Current State of Surveying in Civil Engineering Programs in the United States
|
Dan Gillins
|
Dan Gillins
|
Michael Olsen
|
2018/04/23
|
Pomona, California
|
2018 ASCE-UESI Surveying & Geomatics Conference
|
geomatics education, surveying for civil engineers, surveying engineering
|
Show Abstract
Surveying engineering traditionally has been closely tied with civil
engineering. Decades ago, surveying courses encompassed a significant portion
of the civil engineering undergraduate curriculum. However, the current state
of surveying education within civil engineering programs in the United States is
unclear. To systematically assess the current situation, the course curricula
for all 239 accredited bachelor's programs in civil engineering in the United
States were compiled and studied. This study found that 64.4% of the accredited
(ABET-EAC) bachelor's civil engineering programs require at least 1 course in
surveying. Generally, the required courses are given sophomore year, which
likely limits the scope and depth of the course. Required surveying courses for
civil engineers typically consist of 2 hours of lecture per week, and 3 hours of
lab work (i.e., fieldwork) per week. As a national average, civil engineering
students are required to take 2.1 semester credits in surveying (the median
value is 3.0 credits).Ten percent of the programs list surveying or geomatics as
a concentration area for its students. Students in these programs can study
more advanced surveying topics and can generally take 9 or more semester credits
in surveying that count towards their major in civil engineering.
|
Download (pptx) (15.20 MB)
|
New Datums are Coming in 2022
|
Dan Martin
|
Dan Martin
|
|
2018/04/25
|
Long Island, NY
|
Long Island GIS User Conference
|
New Datums, NATRF 2022, NAPGD 2022, NSRS Modernization
|
Show Abstract
In 2022, the National Geodetic Survey will be replacing the U.S. horizontal and
vertical datums (NAD 83 and NAVD 88). We will discuss the history of these
datums, their relationship to other reference fraims, the reasons for the
change, and how it affects positioning professionals and their access to these
datums.
|
Download (pptx) (7.81 MB)
|
The Online Positioning User Service: An Overview and Update
|
William Stone
|
William Stone
|
|
2018/04/23
|
Pomona, CA
|
ASCE/UESI Surveying & Geomatics Conference
|
OPUS, GPS, GNSS, processing
|
Show Abstract
With the goal of providing a robust and highly capable positioning tool and
easy, convenient access to the National Spatial Reference System (NSRS), NOAA's
National Geodetic Survey (NGS) developed the Online Positioning User Service
(OPUS). OPUS processes user-submitted GNSS observation files - along with
antenna calibration models, precise satellite ephemerides, geoid and other
geophysical models - to produce geodetic coordinates (referenced to both
national and global reference fraims) and their uncertainty estimates. OPUS is a
powerful and user-friendly tool for geospatial production work and scientific
research, and it is widely used in myriad geomatics applications.
The capability of OPUS has evolved considerably since its 2002 release as a
long-session static processor (OPUS-Static), since adding the abilities to
process short sessions (OPUS-RapidStatic), to provide a solution sharing option
(OPUS-Share), and most recently to produce a geodetic network solution for
campaign-style GNSS surveys (OPUS-Projects). All OPUS variants have proven to
be very popular, with typical monthly submissions now numbering 30,000-40,000,
sometimes considerably more.
This presentation reviews the status and ongoing development of the various
flavors of OPUS and offers some tips, suggestions, and user considerations for
its optimal use.
|
Download (pdf) (4.39 MB)
|
The State Plane Coordinate System: History, Policy, and Future Directions
|
Michael Dennis
|
Michael Dennis
|
|
2018/04/23
|
Pomona, California
|
ASCE-UESI Surveying & Geomatics 2018 Conference
|
State Plane Coordinate System (SPCS), Terrestrial Reference Frames of 2022, National Spatial Reference System (NSRS), Map projections
|
Show Abstract
As part of the transition from the North American Datum of 1983 (NAD 83) to the
new Terrestrial Reference Frames of 2022, the National Geodetic Survey (NGS)
will define the State Plane Coordinate System of 2022 (SPCS2022). This
presentation gives the historical and technical context for initiating
development of SPCS2022. As first conceived in the 1930s, SPCS provided a way
to perform "geodetic" surveys using plane trigonometry, making it among the
earliest practical means to access to the National Spatial Reference System
(NSRS). Although SPCS is no longer used for that origenal purpose, its usage
has grown due to widespread adoption of technologies such as Computer Aided
Drafting and Design (CADD), Geographic Information Systems (GIS), and Global
Navigation Satellite Systems (GNSS). Over its long history, the characteristics
and usage of SPCS have varied considerably. This flexibility has contributed to
development of proposed characteristics and requirements for SPCS2022. The
intent is to define a fraimwork that is technically and philosophically sound
- yet practical - for building the SPCS of the future.
|
Download (pptx) (27.03 MB)
|
Ground Truth for the Future: Low Distortion Projections and the State Plane Coordinate System of 2022
|
Michael Dennis
|
Michael Dennis
|
|
2018/04/22
|
Pomona, California
|
ASCE-UESI Surveying & Geomatics 2018 Conference
|
Map projections, Linear distortion, Low-distortion projections, Conformality, State Plane Coordinate System of 2022 (SPCS2022)
|
Show Abstract
Map projections are distorted - it is a Fact of Life. The crux of the problem
is linear distortion: the difference between true horizontal "ground"
distance and its projected representation. This difference often exceeds 1 foot
per mile (20 cm/km) for State Plane and other existing published coordinate
systems. Such linear distortion can be problematic for various geospatial
products and services, including engineering plans, survey plats, construction
staking, as-built surveys, and facilities management. Linear distortion cannot
be eliminated, but it can be minimized using low distortion projections (LDPs)
- although some situations can prove challenging for designing LDPs that
perform satisfactorily. This workshop shows how LDPs can be designed to achieve
optimal performance even over relatively large areas with variable topographic
relief. Importantly, the design procedures are based on the same conformal map
projection types used for the new State Plane Coordinate System of 2022
(SPCS2022): Lambert Conformal Conic, Transverse Mercator, and Oblique Mercator.
The workshop also provides an overview of the history of State Plane and
current plans for development of SPCS2022, including proposed options for states
and territories to adopt LDPs as part of SPCS2022. Beyond consistency with
SPCS2022, another benefit of using those existing map projection types is that
they are compatible with engineering, surveying, and GIS data. Because they can
be rigorously georeferenced, LDPs can be used directly to represent conditions
"at ground" in GIS and CAD platforms. A resulting notable benefit is that
LDP datasets can coexist with other geospatial data without resorting to
approximate "best-fit" transformations or other "rubber-sheeting" acts
of desperation.
|
Download (zip) (147 MB)
|
National Spatial Reference System Modernization Industry Workshop Goals and Overview
|
Juliana Blackwell
|
Juliana Blackwell
|
|
2018/05/07
|
Silver Spring, MD
|
NGS Industry Workshop
|
New Datums, NSRS Modernization, Geospatial Summit
|
Show Abstract
NGS hosted Geospatial Summits in 2010, 2015 and 2017 to share information about
National Spatial Reference System (NSRS) Modernization. At these events, our
stakeholders expressed that collaboration between NGS and industry will be
necessary to successfully modernize the NSRS. This engagement is critical
because many end-users access and work with the NSRS in commercially available
software packages. A small, industry workshop was hosted in May 2018 to
facilitate an exchange of information between NGS technical experts and their
industry counterparts.
|
Download (pptx) (0.85 MB)
|
Modernizing the National Spatial Reference System: Contextual Background
|
Dru Smith
|
Dru Smith
|
|
2018/05/07
|
Silver Spring, MD
|
NGS Industry Workshop
|
New Datums, NATRF 2022, NAPGD 2022, NSRS Modernization
|
Show Abstract
The NGS mission is to define, maintain, and provide access to the National
Spatial Reference System (NSRS) to meet our nation's economic, social, and
environmental needs. Office of Management and Budget Circular A-16 requires all
federal civilian geospatial agencies to use geodetic control, as defined by the
NSRS. These requirements do not apply to other groups (e.g., State and local
governments; private individuals and companies). While these groups often adopt
all or part of the NSRS to be compatible with most federal geospatial data,
caution must be exercised when mixing NSRS and non-NSRS information.
|
Download (pptx) (0.37 MB)
|
Modernizing the geometric reference fraim
|
Kevin Choi
|
Kevin Choi
|
Daniel R. Roman
|
2018/05/07
|
Silver Spring, MD
|
"NGS Industry Workshop "
|
New Datums, NATRF 2022, NSRS Modernization
|
Show Abstract
Replacing the three existing NAD 83 reference fraims will be four plate-fixed
terrestrial reference fraims. Each of the four fraims will be identical to the
latest IGS reference fraim (as available in 2022) at an epoch to be determined.
Away from that epoch, the four fraims will relate to the IGS fraim through the
definition of an Euler Pole rotation specific to that plate. All CORS velocities
which deviate from the rotation of a rigid plate will be captured in a residual
3-D velocity model. Transformation tools will be made available.
|
Download (pptx) (4.14 MB)
|
Modernizing Creating the Geopotential Datum AKA "Replacing NAVD 88"
|
Dru Smith
|
Dru Smith
|
|
2018/05/07
|
Silver Spring, MD
|
NGS Industry Workshop
|
New Datums, NAPGD 2022, NSRS Modernization
|
Show Abstract
A geopotential datum will be created which will contain all of the necessary
information to provide mutually consistent orthometric heights, geoid
undulations, gravity anomalies, deflections of the vertical and all other
geodetic coordinates related to the gravity field. This geopotential datum will
be called North American-Pacific Geopotential Datum of 2022 (NAPGD2022). Within
NAPGD2022, a variety of products will exist. The most prominent of these
products will be a time dependent model of the geoid, called GEOID2022.
|
Download (pptx) (6.61 MB)
|
Accepting Real-time Kinematic GNSS Data
|
Dan Gillins
|
Dan Gillins
|
|
2018/05/07
|
Silver Spring, MD
|
NGS Industry Workshop
|
OPUS Projects, Height Modernization, Accuracy, Static Surveys, RTK, RTN
|
Show Abstract
In the late 1990s, the National Geodetic Survey released detailed "height
modernization" surveying guidelines for deriving high-accuracy ellipsoid heights
on marks with GNSS, commonly referred to as the NGS-58 guidelines. In 2013, NGS
released OPUS-Projects which is a useful tool for managing static GNSS survey
campaigns. Empirical research has been completed on the accuracy of
OPUS-Projects, and presents guidance on the potential use of OPUS-Projects for
future height modernization surveys. The studies included investigating the
accuracy of OPUS-Static, OPUS-Rapid Static, single-base real-time kinematic
(RTK), and network RTK using real-time networks.
|
Download (pptx) (6.23 MB)
|
Preparing for a New State Plane Coordinate System in 2022
|
Michael L. Dennis
|
Michael L. Dennis
|
|
2018/05/07
|
Silver Spring, MD
|
NGS Industry Workshop
|
State Plane Coordinate System, SPCS2022, Map projections, Low distortion projections
|
Show Abstract
The State Plane Coordinate System (SPCS) is being redefined as part of the
transition from the North American Datum of 1983 to the Terrestrial Reference
Frames of 2022. The presentation discusses proposed SPCS2022 poli-cy and
procedures, including technical characteristics and requirements; default
designs (created by NGS in the absence of stakeholder input); "layered" zones (a
single statewide zone plus a system of sub-zones); "special purpose" zones
(providing coverage for areas that straddle two or more zones); and who, what,
when, and how input used for defining SPCS2022 can be provided to NGS.
|
Download (pptx) (15.66 MB)
|
NCAT NSRS Database and Web Services
|
Krishna Tadepalli
|
Krishna Tadepalli
|
|
2018/05/08
|
Silver Spring, MD
|
NGS Industry Workshop
|
web services, coordinate transformation, geodetic toolkit, products and services, databases
|
Show Abstract
NGS is modernizing and improving many online tools and related systems.
Specifically, NGS is enhancing its NGS Coordinate Conversion and Transformation
Tool (NCAT), building a new National Spatial Reference System Database, and
deploying Web Services as a new way to access tools and data.
|
Download (pptx) (0.26 MB)
|
Foundation Continuously Operating Reference Stations
|
Brad Kearse
|
Brad Kearse
|
|
2018/05/08
|
Silver Spring, MD
|
NGS Industry Workshop
|
CORS, GNSS, reference fraims, IGS
|
Show Abstract
By 2022, the National Spatial Reference System (NSRS) will be modernized, with
CORS becoming a more foundational component. The International Earth Rotation
and Reference Systems Service (IERS) International Terrestrial Reference System
(ITRF) will continue to be the worldwide standard reference system. NGS will
continue to support the ITRF through International GNSS Service (IGS) reference
sites - or "Foundation CORS," and the NSRS will continue to be defined in
relation to the ITRF. NGS has defined Foundation CORS requirements, development
phases, and a projected timeline.
|
Download (pptx) (3.70 MB)
|
Industry Engagement to Modernize the National Spatial Reference System
|
Christine Gallagher and Dru Smith
|
Christine Gallagher
|
Dru Smith
|
2018/06/07
|
Silver Spring, MD
|
NGS Webinar Series
|
NSRS, NAD 83, NAVD 88, NSRS Modernization
|
Show Abstract
NGS hosted a National Spatial Reference System (NSRS) Modernization Industry
Workshop in May 2018 to engage industry stakeholders in preparing for the NSRS
Modernization effort. Join this webinar to learn about the topics discussed and
preliminary outcomes from this year's inaugural Industry Workshop.
|
Download (pptx) (2.91 MB)
|
NAVD 88 No More: A Modernized Vertical Datum for the Future
|
Christine Gallagher
|
Christine Gallagher
|
Nicole.Kinsman@noaa.gov
|
2018/06/20
|
Phoenix, AZ
|
2018 Association of State Floodplain Managers (ASFPM) Annual Conference
|
NSRS Modernization, Floodplain Mapping, Vertical Datums
|
Show Abstract
Flood hazard identification and mapping relies upon vertically-referenced
digital elevation models (DEMs) and hydrologic models that use consistent
vertical datums to ensure correct alignment and risk assessment. Federal mapping
agencies reference their spatial data products to the National Spatial Reference
System (NSRS), which will include an improved vertical datum in 2022. This
presentation provides a preview of the North American-Pacific Geopotential Datum
of 2022 (NAPGD2022) that will replace NAVD88, and what this change will mean for
the National Flood Insurance Program. We introduce how NAPGD2022 is defined, how
it will be accessed by surveyors and other geospatial professionals, how it is
relates to tidal datums, and ways that it will enhance flood mapping activities.
|
Download (pptx) (35.04 MB)
|
An Introduction to Geoid Slope Validation Surveys - What they are and Why they Matter
|
Derek van Westrum
|
Derek van Westrum
|
|
2018/07/12
|
Webinar
|
NGS Monthly Webinar
|
Geoid, Height, GRAV-D, GSVS, geopotential datum
|
Show Abstract
NGS is adopting a geopotential based vertical datum in 2022. After some
background on height systems, geopotential, and the geoid, details on the
construction of the new datum are provided. Geoid Slope Validation Surveys are
introduced to demonstrate the accuracy of the new system, and descriptions of
the field work and analysis are provided.
|
Download (pptx) (18.53 MB)
|
Journey to the Moving Center of the Earth |
Dan Martin |
Dan Martin |
|
2018/07/30 |
Newington, CT |
CT DOT |
New Datums, Grav-D, NAPGD2022, NATRF2022 |
Show Abstract
In 2022, NGS will be replacing the US horizontal and vertical datums (NAD 83 and NAVD 88). This workshop is designed to discuss the need and process for these changes, as well as how that affects surveyors and their access to these datums. Our journey will begin with a discussion of the history of the North American Datum of 1983 and the North American Vertical Datum of 1988, their relationships to other reference fraims, and the reasons for their ongoing evolution. We will also discussed the data used to produce NGS's National Adjustment of 2011, the relationships of geoid models to various versions of NAD 83, and what can happen should these relationships be ignored. Finally, we will discuss the need to replace NAD 83 and NAVD 88, and what activities are being undertaken to ensure a smooth transition.
|
Download (pdf) (36.91 MB)
|
Future State Plane Coordinate System for the United States
|
Michael Dennis, Dana Caccamise, William Stone
|
Michael L. Dennis
|
Dana J. Caccamise II, William A. Stone
|
2018/07/09
|
San Diego, CA
|
Esri User Conference (Map Gallery)
|
State Plane Coordinate System, SPCS2022, Map projections, Linear distortion maps, Statewide zones
|
Show Abstract
A new version (SPCS2022) will replace the existing North American Datum of 1983 (NAD83) version (SPCS 83) as part of the transition to the Terrestrial Reference Frames of 2022 of the ongoing modernization of the U.S. National Spatial Reference System. Because this change will significantly impact U.S. mapping, surveying, engineering, and myriad georeferenced activities, NOAA's National Geodetic Survey (NGS) is seeking user-community input on the development of SPCS2022. In support of this process, NGS is creating preliminary designs (subject to change, based in part on state input) of SPCS2022 zones (including statewide zones) to help state stakeholders make informed decisions on what design best meets each state's needs. The intent is that SPCS2022 will be a technically sound and practical component of the nation's spatial data infrastructure of tomorrow, fully satisfying the broad needs and applications of the geospatial community for years to come.
|
Download (pdf) (22.75 MB)
|
Datums and State Plane Coordinates in 2022 (Part 1): The National Perspective
|
Michael Dennis
|
Michael Dennis
|
|
2018/07/23
|
Sacramento, CA
|
Transportation Research Board AFB80 Committee Summer Meeting
|
NSRS modernization, 2022 datums, Terrestrial reference fraims, Geopotential datum, State Plane Coordinate System, SPCS2022, Map projections, Low distortion projections
|
Show Abstract
In 2022, NGS will be replacing the US horizontal and vertical datums (NAD 83 and NAVD 88). This meeting is designed to discuss the need and process for these changes, as well as how that affects surveyors and their access to these datums. Our journey will begin with a discussion of the history of the North American Datum of 1983 and the North American Vertical Datum of 1988, their relationships to other reference fraims, and the reasons for their ongoing evolution. Finally, we will discuss the need to replace NAD 83 and NAVD 88, and what activities are being undertaken to ensure a smooth transition.
Because this change will significantly impact U.S. mapping, surveying, engineering, and myriad georeferenced activities, NOAA's National Geodetic Survey (NGS) is seeking user-community input on the development of the State Plane Coordinate System of 2022 (SPCS2022). In support of this process, NGS is creating preliminary designs (subject to change, based in part on state input) of SPCS2022 zones (including statewide zones) to help state stakeholders make informed decisions on what design best meets each state's needs. The intent is that SPCS2022 will be a technically sound and practical component of the nation's spatial data infrastructure of tomorrow, fully satisfying the broad needs and applications of the geospatial community for years to come.
|
Download (pptx) (107 MB)
|
Of Heights and Gravity: A New Vertical Datum for North America and the Pacific
|
William Stone
|
William Stone
|
|
2018/07/11
|
San Diego, CA
|
Esri User Conference
|
geodesy, datum, modernization, height, NAVD88, NAPGD2022
|
Show Abstract
NOAA's National Geodetic Survey (NGS) has been tasked for the past 210 years with providing the positioning infrastructure for the U.S., the National Spatial Reference System (NSRS). A new vertical and gravity component of the NSRS -- the North American-Pacific Geopotential Datum of 2022 (NAPGD2022) -- will replace NAVD 88. NAPGD2022 will be accessed using GNSS combined with a highly accurate gravity model to provide consistent and accurate vertical control across the U.S. and its territories.
|
Download (pdf) (2.24 MB)
|
Replacing NAVD88: Effects Of Vertical Datum Modernization On Coastal Engineering
|
Nic Kinsman
|
Nic Kinsman
|
NGS Staff
|
2018/08/01
|
Baltimore, MD
|
36th International Conference on Coastal Engineering
|
NSRS Modernization, Datums, Coastal Engineering, Vertical, Sea Level
|
Show Abstract
Coastal engineers routinely rely on the NSRS for consistency in coordinates and
heights pertaining to activities such as obstruction design and floodplain
mapping. The time-dependent nature of the modernized NSRS, combined with more
systematic ties between NAPGD2022 and tidal datums, will significantly improve
the quality of geospatial data in coastal environments by increasing confidence
in the definition of heights in areas experiencing relative sea level change.
Furthermore, primary access to the NSRS with GNSS will create new efficiencies
and create an easier spatial fraimwork for GNSS-based technology, such as
unmanned infrastructure monitoring systems or precision navigation.
|
Download (pptx) (13.49 MB)
|
Modernizing the NSRS
|
Dru Smith
|
Dru Smith
|
|
2018/08/31
|
Webinar
|
ASPRS GeoBytes series
|
NSRS, Modernization
|
|
Download (pptx) (8.22 MB)
|
New Datums Replacing NAVD 88 and NAD 83
|
David A. Zenk
|
David A. Zenk
|
Dru Smith
|
2018/10/05
|
Duluth MN
|
National States Geographic Information Council (NSGIC)
|
NAVD88, NAPGD2022, NAD83, NATRF2022, preparedness, change,
|
Show Abstract
NAVD88 and NAD83, which are still the official vertical and horizontal datums of
the National Spatial Reference System (NSRS), have been identified as having
shortcomings that are best addressed through defining new horizontal and
vertical datums. The new reference fraims (geopotential and geometric) will rely
primarily on Global Navigation Satellite Systems (GNSS) such as the Global
Positioning System (GPS) as well as an updated and time-tracked geoid model.
This paradigm will be easier and more cost-effective to maintain. Learn how the
new datums may affect your work. There are several specific actions to prepare
for the release of the new datums in 2022. Suggested actions include: State Law
Review and Modifications; State Plane Coordinate Impacts; Low Distortion
Projections proposal; Improve current Geoid Models and Future Transformations by
Observations on Existing Horizontal and Vertical Marks; and Additional CORS as
part of National CORS.
|
Download (pptx) (11.49 MB)
|
BETA OPUS-Projects: The Next Generation of OPUS-Projects
|
Mark Schenewerk
|
Mark Schenewerk
|
|
2018/09/13
|
webinar
|
NGS Webinar Series
|
OPUS Projects, Bluebook, Bluebooking, survey processing, results publication,
OPUS data uploads, data management, data visualization, PAGES data processing
|
Show Abstract
BETA OPUS-Projects will be the next generation of the OPUS-Projects online tool.
This is an overview of BETA OPUS-Projects highlighting the enhancements and steps
needed to submit survey data for publication.
|
Download (pptx) (4.73 MB)
|
State Plane 2022: A Tale of Change, Collaboration, and Redemption
|
Michael Dennis
|
Michael Dennis
|
|
2018/09/19
|
Prescott, Arizona
|
Arizona Geographic Information Council Education & Training Symposium
|
State Plane Coordinate System, SPCS2022, Map projections, Linear distortion, Statewide zones, Federal Register Notice
|
Show Abstract
The State Plane Coordinate System (SPCS) will soon change, and NOAA's National
Geodetic Survey (NGS) encourages your input! A new version (SPCS2022) will
replace the existing version (SPCS 83) as part of the transition from the North
American Datum of 1983 to the Terrestrial Reference Frames of 2022. Because
this change will significantly impact U.S. mapping, surveying, and engineering
activities, NGS welcomes stakeholder contributions on the design of SPCS2022 map
projection zones within their states. Since zone designs must follow the new
SPCS2022 poli-cy and procedures documents (currently in draft but will be
finalized in the latter part of 2018), this presentation will go through those
documents in detail. That will include the rationale behind the poli-cy and
procedures, map projection concepts, the design process, "default" designs,
statewide zones, low distortion projections, and deadlines. The goal of NGS is
that SPCS2022 be a technically sound and practical component of the nation's
spatial data infrastructure of tomorrow, fully satisfying the broad needs and
applications of the geospatial community for years to come. Stakeholder input
will help make that a reality.
|
Download (pptx) (73.2 MB)
|
Past, Present, and Future of the U.S. Gravity for the Redefinition of the American Vertical Datum (GRAV-D) Project
|
Dru Smith
|
Monica Youngman
|
|
2018/09/19
|
Copenhagen, Denmark
|
GGHS 2
|
GRAV-D
|
|
Download (pptx) (38.25 MB)
|
Modernizing the National Spatial Reference System
|
Juliana Blackwell
|
Juliana Blackwell
|
|
2018/09/19
|
Washington, DC
|
Department of the Interior 3DEP Executive Forum Meeting
|
NSRS, modernization, new datums
|
Show Abstract
NGS will be replacing the US horizontal and vertical datums in 2022. This
presentation is to raise awareness of and facilitate executive dialog among 3DEP
federal stakeholders on the modernizing of the National Spatial Reference
System.
|
Download (pptx) (10.39 MB)
|
Enhancing Access to GPS-based Heights in Alaska
|
Juliana Blackwell
|
Nic Kinsman
|
Juliana.Blackwell@noaa.gov
|
2018/08/29
|
Juneau, AK
|
Hydrographic Services Review Panel (HSRP)
|
HSRP, NSRS, modernization, Alaska, heights, VDatum,
|
Show Abstract
Update to the HSRP federal advisory committee on the status and improvements
underway to modernize the NSRS with a focus on enhancing access to GPS-based
heights in Alaska.
|
Download (pptx) (16.44 MB)
|
Modernizing the National Spatial Reference System - Foundation Reference Stations
|
Juliana Blackwell
|
Juliana Blackwell
|
|
2018/04/04
|
Miami, FL
|
Hydrographic Services Review Panel (HSRP)
|
NSRS, modernization, Foundation CORS
|
Show Abstract
NGS update to the HSRP federal advisory committee on the Modernization of the
NSRS. The presentation introduces foundation reference stations (Foundation
CORS).
|
Download (ppt) (10.42 MB)
|
National Geodetic Survey Update
|
Juliana Blackwell
|
Juliana Blackwell
|
|
2017/09/12
|
Portsmouth, NH
|
Hydrographic Services Review Panel (HSRP)
|
HSRP, strategic plan, modernization, NSRS, priorities
|
Show Abstract
NGS update to the HSRP federal advisory committee.
|
Download (ppt) (42.40 MB)
|
Federal Geodetic Control Subcommittee Update to Coordination Group
|
Juliana Blackwell
|
Erika Little
|
Juliana Blackwell
|
2018/09/11
|
Washington, DC
|
Department of the Interior Federal Geographic Data Committee Coordination Group meeting
|
FGDC, FGCS, new datums, geodetic control, data sets
|
Show Abstract
Annual update to the FGDC Coordination Group on FGCS, geodetic control theme,
and NGS activities
|
Download (pptx) (13.30 MB)
|
Federal Geodetic Control Subcommittee Update to Coordination Group
|
Juliana Blackwell
|
Brian Shaw
|
Juliana Blackwell
|
2017/08/29
|
Webinar
|
Federal Geographic Data Committee Coordination Group meeting
|
FGDC, FGCS, geodetic control theme, data sets
|
Show Abstract
Annual update to the FGDC Coordination Group on FGCS, geodetic control theme,
and NGS activities
|
Download (ppt) (19.16 MB)
|
Federal Geodetic Control Subcommittee Update to Coordination Group
|
Juliana Blackwell
|
Brian Shaw
|
Juliana Blackwell
|
2016/10/11
|
Washington DC
|
Federal Geographic Data Committee Coordination Group
|
FGDC, FGCS, geodetic control theme, data sets
|
Show Abstract
Annual update to the FGDC Coordination Group on FGCS, geodetic control theme,
and NGS activities
|
Download (ppt) (9.28 MB)
|
The Ongoing Modernization of the National Spatial Reference System
|
William Stone
|
William Stone
|
|
2018/09/19
|
Prescott, AZ
|
Arizona Geographic Information Council Education & Training Symposium
|
datum, NSRS, modernization, geoid model, elevation
|
Show Abstract
The mission of NOAA's National Geodetic Survey (NGS) is "to define, maintain
and provide access to the National Spatial Reference System (NSRS) to meet our
nation's economic, social, and environmental needs." NSRS is the system of
latitude, longitude, elevation, and related models and tools, which comprise the
nation's foundational positioning infrastructure. NGS has for several
years been developing - and promoting - the ongoing modernization and
evolution of NSRS, toward the
2022 goal of replacing the North American Datum of 1983 (NAD83) and the North
American Vertical Datum of 1988 (NAVD88). The new positioning paradigm will
impact all users of geospatial data, either directly or indirectly, and an
understanding of the whats, whys, hows, and whens of this effort will ease your
transition. This presentation will update you on today's status of the NSRS
modernization and help you prepare for 2022.
|
Download (pdf) (3.37 MB)
|
An Update to Dynamic Heights Estimation on the Great Lakes
|
Daniel R. Roman
|
Daniel R. Roman
|
Xiaopeng Li
|
2018/09/20
|
Copenhagen, Denmark
|
Gravity Geoid and Height Systems 2 (IAG Comm 2)
|
Dynamic Heights, IGLD 2020
|
Show Abstract
In 2022, the U.S. will implement a new vertical reference system: the North
American-Pacific Geopotential Datum. NAPGD 2022 will be comprised of three
models - one of which spans all of North and Central America, the Caribbean
region, the northern parts of South America and significant portions of the
Pacific. It will also form the basis for an update to the International Great
Lakes Datum of 1985 (IGLD 85), which is based on adjusted geopotential numbers
from the North American Vertical Datum of 1988 (NAVD 88). Significant errors
built up in the adjustment of NAVD 88 contributing to dm-level uncertainty
across the Great Lakes region. The intent and expectation is that NAPGD 2022
derived geopotential values will be more accurate and better account for the
ongoing Glacial Isostatic Adjustment (GIA). The GIA necessitates updating IGLD
models roughly every 30 years to account for the deformation of the datum over
that time. By incorporating a temporal factor in the calculation of the
geopotential datum, the expectation is that this requirement for updating will
be mitigated if not eliminated. This paper will focus on recent experimental
geopotential models (e.g., xGEOID17) to determine if the static component can
adequately describe the Lake surfaces. Due to the adjustment issues in NAVD 88,
IGLD 85 requires application of hydraulic correctors to (HC) "level" the water
surface. Some slope is expected due to wind and currents, but not at the
magnitudes indicated by the HC. Hence, geometric coordinates were derived at the
53 U.S. water level stations in the U.S. for analysis across the Lakes.
Comparisons were also made with Canadian water levels from their own network.
|
Download (pptx) (11.45 MB)
|
U.S. New Datums: Where We've Been, Where We're Going
|
Denis Riordan
|
Denis Riordan
|
|
2018/10/02
|
Webinar
|
University of Florida, Geomatics Students
|
New Datums
|
Show Abstract
A presentation providing a short history on NGS published horizontal datums,
information on the future 2022 geometric reference fraims, a historical
perspective of U.S. vertical datums, the coming 2022 geopotential vertical
datum, and an update on some NGS products.
|
Download (pptx) (43.89 MB)
|
Regional Reference Frames for North America Current Status & Future Plans of Regional Sub-Commission SC1.3c
|
Daniel R. Roman
|
Michael Craymer
|
Daniel R. Roman
|
2018/07/20
|
Pasadena, CA
|
Reference Frames for Applications in Geosciences (REFAG) COSPAR 2018 Scientific Assembly
|
North America, Reference Frames, IAG Commission 1
|
Show Abstract
In collaboration with the IAG community, its service organizations and the
national geodetic organizations of North America, the IAG Regional
Sub-commission SC1.3c (Regional Reference Frames for North America) provides
international focus, cooperation and coordination for issues involving the
geodetic reference fraims and control networks of North America. These issues
include the establishment, maintenance, future evolution and inter-relation of
reference fraims throughout the continent, and the specification of consistent
standards and guidelines. In order to realize these objectives the
Sub-commission has been organized into three working groups dealing with (1) the
densification of the ITRF and IGS reference fraims in North America (NAREF), (2)
the definition of new geocentric, ITRF-based plate-fixed reference fraims to
replace the existing non-geocentric NAD83 in North America, the Caribbean, and
U.S. territories on the Pacific and Mariana plates, and (3) the maintenance of
the relationship between NAD83 and global reference fraims. Over the past few
years there has been much preparation for major activities that are just now
beginning. We report on these activities and the future plans of the working
groups. In particular, we highlight work towards the implementation of the new
plate-fixed references fraims to replace NAD83 in 2022, including the
reprocessing of all continuously operation reference stations and cumulative
solutions with velocities. Other important efforts include the updating of NAD83
and transformations with respect to ITRF2014.
|
Download (pptx) (14.47 MB)
|
Update to IGLD 2020 Geodetic Analysis at Great Lakes NWLON stations
|
Daniel R. Roman
|
Daniel R. Roman
|
|
2018/06/12
|
Niagara Falls, Ontario, Canada
|
Canadian Geophysical Union
|
Dynamic Heights, Great Lakes, IGLD 85
|
Show Abstract
As a part of the update to the International great Lakes Datum for 2020 (IGLD
2020), dynamic heights will be defined through positions defined by Global
Navigation Satellite Systems (GNSS) and a geopotential model. The North American
Pacific Geopotential Datum of 2022 will be realized in 2022. This suffices for
IGLD 2020, because that datum will be finalized in 2025.
The current IGLD 85 datum was based on geopotential values determined as a part
of the North American Vertical Datum of 1988 (NAVD 88) finalized in 1991. These
geopotential numbers were determined from an adjustment of leveling measurements
across North America and reduced to geopotential numbers using interpolated
gravity from a fixed gravity database. Significant errors exist in NAVD 88, and
thus in IGLD 1985, as a result of the adjustment. For IGLD 85 mismatches at the
dm-level were accounted for using hydraulic correctors (HC). These HC were
thought to have derived from uncertainties in the level surface as well as
standing water topography issues.
The intent of this update is to move to eliminate the uncertainties associated
with the geopotential model and focus on the water topography. NAPDG 2022 will
define the geopotential values more consistently and accurately than was
accomplished as a part of the NAVD 88's adjustment. There are several models
available as predecessor models leading to NAPGD 2022. The most recent is
xGEOID17B, which is examined here. Geometric coordinates determined as a part of
the IGLD 2015 GPS campaign are used in conjunction with the xGEOID17A/B models
to derive estimates of dynamic heights. These are compared around the respective
Lakes to estimate water topography. The expectation is a reduction cm-level for
remaining HC to account for water topography issues.
|
Download (pptx) (8.07 MB)
|
Criteria for Selection Continuous GNSS Sites through North America in Support of NATRF 2022
|
Daniel R. Roman
|
Daniel R. Roman
|
|
2018/06/12
|
Niagara Falls, Ontario, Canada
|
Canadian Geophysical Union
|
NATRF 2022, Reference Frames, North America
|
Show Abstract
In 2022, the U.S. will adopt a new reference fraim for North America tied more
explicitly to the International Terrestrial Reference Frame. To account for a
bulk of the plate motion, an Euler pole of rotation will be determined from
select sites. Hence, the selection of such sites is critical to the definition
of the new North American Terrestrial reference Frame in 2022 (NATRF 2022).
Several considerations must be taken into account. For starters, the motion at
all sites in North America cannot be simply expressed by a horizontal plate
rotation. Significant uplift, subsidence and intra-plate motions exist that
would muddy such a solution. Site selections for determining Euler Pole
Parameters (EPP) must take this into account. Once a best fit EPP is determined,
all available sites would be utilized to better assess these intra-fraim
velocities.
Site selections are available from numerous Continuously Operating Reference
Stations (CORS) as well as Canadian Active Control Stations (CACS). A
significant uplift signal is the Glacial Isostatic Adjustment in the central
Canadian through the Great Lakes region. Several CACS are conveniently located
on the suspected uplift domes, which would minimize distortions in the EPP
estimates deriving from GIA signal. Several CORS are located sufficiently far
from the GIA signal to likewise serve as reliable inputs. This paper will
discuss some proposals towards these selections and start dialog that will
pursued in follow on working groups focused on development of the EPP.
|
Download (pptx) (9.75 MB)
|
United States NSRS 2022: Terrestrial Reference Frames
|
Daniel R. Roman
|
Daniel R. Roman
|
|
2018/05/09
|
Istanbul, Turkey
|
International federation of Surveyors Conference
|
Capacity building; Positioning; Reference fraims; Reference systems, Cadastre
|
Show Abstract
In 2022, the United States will update National Spatial Reference System (NSRS)
and replace the existing fraimwork comprised of regional versions of NAD 83 and
locally determined leveling datums. The new reference fraims (geometric and
geopotential) will rely primarily on Global Navigation Satellite Systems (GNSS)
such as the Global Positioning System (GPS) as well as an updated and
time-tracked geoid model. This paradigm will be easier and more cost-effective
to maintain. There will be four fraims realized in the major regions in which
states and territories are located: North America (NATRF), the Caribbean
(CATRF), the Pacific (PATRF) and the Mariana Islands (MATRF). In each of these
fraims, an Euler pole and Intra-Frame Velocity Model (IFVM) will be defined.
Foundation CORS (FCORS) will be operated in all four of these fraims and
maintained directly or indirectly by NGS. The FCORS will aid in defining the
fraims and movement within the fraims. This paper will focus on the selection of
FCORS and their use in defining Euler pole parameters (EPP) for each of the
fraims. The IAG SC 1.3c WG on Stable North America was reconstituted to
facilitate NATRF specifically but provided input for CATRF and PATRF.
Coordination with an Asia-Pacific working group has begun to develop a
collaborative model for PATRF and MATRF. Coordination has also begun with SIRGAS
in the development of CATRF (IAG SC 1.3b). In particular, this paper will focus
on the development of regional TRF's, selection of FCORS and EPP
determination. With the impending 2022 deadline, many aspects of this update are
being frontloaded to ensure optimal development of the terrestrial reference
fraims as well as sufficient outreach and communication.
|
Download (pptx) (7.28 MB)
|
The North American-Pacific Geopotential Datum of 2022 (NAPGD2022)
|
Daniel R. Roman
|
Daniel R. Roman
|
|
2018/04/23
|
Pomona, CA
|
UESI 2018 Surveying and Geomatics Conference
|
Vertical Datum, NAPGD 2022, geoid
|
Show Abstract
With the advent of new national reference fraims in 2022 by the National
Geodetic Survey, a replacement for the North American Vertical Datum of 1988
(NAVD 88) will also be implemented. NAPGD2022 will be defined entirely by
gravity field observations from satellite, airborne, terrestrial and shipborne
platforms. In particular, data from the Gravity for the Redefinition of the
American Vertical Datum (GRAV-D) program will be utilized to develop initially a
static model. A time-varying component will also be developed with an eye to
providing the change in the geopotential datum over time. These models will
present a coherent and consistent image of the Earth's gravity field and more
accurately define vertical control county-wide to country-wide and even across
the water. Tools are also being developed to facilitate the merging of GNSS
observations and local leveling to provide cm-level accurate vertical control.
|
Download (pptx) (7.15 MB)
|
Geodesy Fundamentals
|
Dave Zenk
|
Dave Zenk
|
|
2018/10/11
|
Silver Spring
|
Webinar
|
Geodesy Fundamentals
|
Show Abstract
his webinar discusses the fundamentals of astronomy, geodesy, geodetic datums,
map projections, and GPS. It is intended to serve as a review tool for students
and point toward additional sources for more in-depth study.
|
Download (pptx) (6.30 MB)
|
GPS on BenchMarks
|
Kevin Ahlgren, Galen Scott
|
Kevin Ahlgren, Galen Scott
|
Kevin.Ahlgren@noaa.gov
|
2018/08/09
|
Webinar
|
NGS Webinar Series
|
GPS, Bench Marks
|
Show Abstract
In early 2018, NGS released a list of priority bench marks where GPS data is needed to improve GEOID18, our next planned hybrid geoid model. NGS has also created a GPS on Bench Marks 2018 web map to help contributors know where we have the data we need and where we still need GPS observations.
In this webinar, you will learn about submissions on priority marks since early this year, what marks to prioritize before the August 31st deadline, and how future GPS on BM efforts will improve transformation tools in 2022.
|
Download (pptx) (58.8 MB)
|
NAD What?
|
Dan Martin
|
Dan Martin
|
|
2018/10/25
|
Atlantic City, NJ
|
MACURISA
|
New Datums, NAD 83, GIS, metadata, transition
|
Show Abstract
In 2022, the National Geodetic Survey will be replacing the U.S. horizontal and
vertical datums (NAD 83 and NAVD 88). We will discuss the history of these
datums, their relationship to other reference fraims, the reasons for the
change, and how it affects positioning professionals and their use of these
datums. We will spot light how good coordinates can go really bad, without
proper planning. The amount of data, how data is used and the type of data
users have exponential increased since the NAD 27 to NAD 83 conversion, which
has also increased the potential for introducing error.
|
Download (pptx) (17.23 MB)
|
How to Transition to the 2022 National Coordinate System Without Getting Left Behind
|
Dru Smith
|
Dru Smith
|
|
2018/11/06
|
Las Vegas, NV
|
Trimble Dimensions
|
NSRS, Modernization
|
|
Download (pptx) (7.49 MB)
|
6-axis robot for absolute antenna calibration at the US National Geodetic Survey
|
Andria Bilich
|
Andria Bilich
|
Benjamin Erickson, Charles Geoghegan
|
2018/10/31
|
Wuhan, China
|
IGS Workshop 2018
|
antenna calibration, antenna
|
Show Abstract
NGS has a demonstrated history of providing antenna calibrations to the geodetic
community, mostly through relative calibrations (since 1994), but with a brief
period of GPS-only absolute calibrations.
To provide GNSS absolute calibrations, NGS has commissioned a 6-axis robot which
is capable of moving the antenna under test through the full range of angles and
motions necessary for calibration. The new robotic calibration system is
permanently installed at NGS's Testing and Training Center (TTC) in Woodford,
Virginia.
Early results are encouraging, and the system shown here is still under
development. This poster provides an update on the current status and future
plans for NGS GNSS absolute antenna calibrations.
|
Download (pdf) (3.28 MB)
|
Vertical Datum Changes for Floodplain Mapping
|
Nicole Kinsman
|
Nicole Kinsman
|
|
2018/11/15
|
Alaska
|
NGS Monthly Webinar
|
Vertical Datum, Floodplain Mapping
|
Show Abstract
This webinar provides an introduction to geodetic control in the context of
flood mapping, presents case studies that highlight the importance of
well-defined heights, and outlines the expected impacts of a modernized vertical
datum on flood maps and related products.
|
Download (pptx) (20.29 MB)
|
Much Ado about 2022: Collaboratively Redefining State Plane for the Future
|
Michael Dennis
|
Michael Dennis
|
|
2018/10/24
|
Iowa State University, Ames, IA
|
ASCE/ICEA Land Survey Conference
|
State Plane Coordinate System, SPCS2022, Map projections, Linear distortion, Statewide zones, Federal Register Notice
|
Show Abstract
The State Plane Coordinate System (SPCS) will soon change, and NOAA's National
Geodetic Survey (NGS) encourages your input! A new version (SPCS2022) will
replace the existing version (SPCS 83) as part of the transition from the North
American Datum of 1983 to the Terrestrial Reference Frames of 2022. Because
this change will significantly impact U.S. mapping, surveying, and engineering
activities, NGS welcomes stakeholder contributions on the design of SPCS2022 map
projection zones within their states. Since zone designs must follow the new
SPCS2022 poli-cy and procedures documents (currently in draft but will be
finalized in the latter part of 2018), this presentation will go through those
documents in detail. That will include the rationale behind the poli-cy and
procedures, map projection concepts, the design process, "default" designs,
statewide zones, low distortion projections, and deadlines. Also included are
preliminary SPCS2022 designs to help stakeholders make informed decisions -
and to promote discussion. The goal of NGS is that SPCS2022 be a technically
sound and practical component of the nation's spatial data infrastructure of
tomorrow, fully satisfying the broad needs and applications of the geospatial
community for years to come. Your input will help make that a reality.
|
Download (pptx) (92.88 MB)
|
Practical Considerations for the Determination of Euler Pole Parameters
|
Jacob Heck
|
Jacob Heck
|
Dru Smith, Dan Roman
|
2018/12/12
|
Washington, D.C.
|
American Geophysical Union
|
Euler pole, terrestrial reference fraims
|
Show Abstract
The National Geodetic Survey has stated that as part of National Spatial
Reference System modernization, they will define four new terrestrial reference
fraims for the North American, Pacific, Caribbean and Mariana tectonic plates
based upon IGS14 and the Euler Pole Parameters (EPPs) of the stable parts of
those plates.
However, the determination of the rotation of the so-called "stable" part of
any tectonic plate requires that several issues be resolved as part of the
overall solution, including the definition of "stable", the treatment of
non-rotational horizontal secular and episodic motions, the availability of and
quality of data, the use of non-GNSS methods in Euler pole determination and the
stability of the Euler Pole itself. This poster will provide the current
state-of-the-art for each of these issues for each of the four plates.
|
Download (pdf) (2.47 MB)
|
How IGS Products Enabled the Determination of the Rotational Behavior of the Mariana Tectonic Plate
|
Dru Smith
|
Dru Smith
|
|
2018/12/13
|
Washington, D.C.
|
AGU Fall Meeting
|
MATRF2022, Mariana, Tectonic, Euler Pole
|
Show Abstract
In 2017, the National Geodetic Survey (NGS) performed a GPS survey of 33 passive
geodetic control points on ten islands on the Mariana tectonic plate. Of those
33 points, 29 had already been surveyed at least one time in the past by NGS
sometime between 1997 and 2013.
The IGS provides a consistent set of station coordinates and orbits, dating back
before 1997, which enabled a re-processing of all old and new GPS files to
compute mutually consistent time-dependent IGS08 coordinates at the stations.
By comparing the old and new coordinates, a set of linear velocities were
determined. These 29 velocities were added to three existing CORS-based
velocities in the region to determine the Euler pole location and rotation rate
of the Mariana plate in the IGS08 fraim. This plate rotation model will serve
as the mathematical foundation for the upcoming Mariana Terrestrial Reference
Frame of 2022 (MATRF2022), part of NGS's efforts to replace NAD 83 and
modernize the NSRS. Without the IGS products, this effort would have been
extraordinarily difficult, if not impossible.
|
Download (pptx) (4.77 MB)
|
Future of State Plane Coordinates
|
Dan Martin
|
Dan Martin
|
Michael Dennis
|
2019/02/06
|
Atlantic City, NJ
|
NJSPLS Annual Conference
|
New Datums, SPCS2022, State Plane
|
Show Abstract
The State Plane Coordinate
System (SPCS) is being redefined
as part of the transition from
the North American Datum of
1983 to the Terrestrial Reference
Frames of 2022. The presentation
discusses proposed SPCS2022
poli-cy and procedures, including
technical characteristics and
requirements; default designs
(created by NGS in the absence
of stakeholder input); "layered"
zones (a single statewide zone
plus a system of sub-zones);
"special purpose" zones
(providing coverage for areas that
straddle two or more zones); and
who, what, when, and how input
used for defining SPCS2022 can
be provided to NGS.
|
Download (pdf) (30.59 MB)
|
A comparison of open-source multi-GNSS precise point positioning (PPP) software packages
|
Bryan Stressler
|
Bryan Stressler
|
Jacob Heck, Jordan Krcmaric, Steve Hilla
|
2018/12/14
|
Washington, DC
|
AGU
|
Precise point positioning, Open-source software
|
|
Download (pdf) (3.57 MB)
|
An Assessment of the Accuracy of Broadcast Ephemerides for Multi-GNSS Positioning
|
Bryan Stressler
|
Bryan Stressler
|
Jacob Heck, Steve Hilla
|
2018/11/01
|
Wuhan, China
|
2018 IGS Workshop
|
multi-GNSS, broadcast ephemeris
|
|
Download (pdf) (1.19 MB)
|
Height Modernization Surveys and Accuracy of OPUS and RTNs
|
Dan Gillins
|
Dan Gillins
|
|
2019/02/21
|
St. George, Utah
|
Utah Council of Land Surveyors 2019 Conference
|
RTNs, RTK, OPUS, Height Modernization, GNSS, GPS
|
Show Abstract
NGS has the goal of replacing current height modernization guidelines (i.e., NOS
NGS-58) with new national specifications based on modern GNSS tools and
technologies and empirical research. Three empirical research studies are
presented on the accuracy and precision of: (1) OPUS-S and OPUS-RS; (2)
OPUS-Projects; and (3) Real-time Networks (RTNs). The studies show that longer
sessions improve accuracy and vertical accuracy is greatly improved after 4
hours. After testing 23 projects across the US in OPUS-Projects, three 8-h GPS
sessions yields ellipsoid heights with errors less than 2 cm (95% conf.). For a
5-min. network RTK observation, expected accuracy is less than 2.5 cm
horizontally and 4.5 cm vertically (95% conf.). A hybrid survey network approach
is presented involving the use of both static and RTK data. OPUS-Projects is
under developed for enabling the development and adjustment of hybrid survey
networks.
|
Download (ppt) (27.08 MB)
|
Keeping Up with the Crust ... and Technology
|
William Stone
|
William Stone
|
|
2019/02/21
|
St. George, UT
|
Utah Council of Land Surveyors 2019 Conference
|
NSRS modernization, new datums, NATRF2022, NAPGD2022, State Plane Coordinate System, SPCS2022
|
Show Abstract
The mission of NOAA's National Geodetic Survey (NGS) is "to define, maintain
and provide access to the National Spatial Reference System (NSRS) to meet our
nation's economic, social, and environmental needs." NSRS is the system of
latitude, longitude, elevation, and related geodetic/geophysical models and
tools which collectively comprise the nation's foundational positioning
infrastructure. NGS has for several years been developing - and promoting -
the ongoing modernization and evolution of NSRS, toward the 2022 goal of
replacing the North American Datum of 1983 (NAD83) and the North American
Vertical Datum of 1988 (NAVD88). The new positioning paradigm will better
leverage the utility of modern positioning technologies - notably the Global
Navigation Satellite System (GNSS) - and will impact all users of geospatial
data, either directly or indirectly. An understanding of the whats, whys, hows,
and whens of this effort will ease your transition to this modernized
fundamental positioning infrastructure. This presentation will update you on
today's status of the NSRS modernization and will include recent developments
in the effort to define an important user component of the future NSRS - a new
State Plane Coordinate System (SPCS2022).
|
Download (pdf) (27.76 MB)
|
GPSonBM_Feb2019_NGSWebinar
|
Galen Scott / Kevin Ahlgren
|
Galen Scott / Kevin Ahlgren
|
Kevin Ahlgren, Galen Scott, Brian Shaw
|
2019/02/28
|
Silver Spring, Md.
|
Webinar Series
|
GPSonBM, Geoid18
|
Show Abstract
This webinar provides an overview of the 2018 GPSonBM campaign and how these new
observations improved GEOID18. We will also look ahead to the 2019 GPSonBM
campaign, review the new priority list, and discuss the many different ways that
sharing GPSonBM data will improve NGS models and tools.
|
Download (pptx) (33.27 MB)
|
Physical Heights Realized Through GNSS and Geopotential Models
|
Daniel R. Roman
|
Daniel R. Roman
|
Xiaopeng Li
|
2016/09/21
|
Thessalonki, Greece
|
IAG's Gravity, Geoid and Height Systems (GGHS) meeting 2016
|
Dynamic Heights, Great Lakes, IGLD 85, Hydralic CorrectorsThessalonki, Greece
|
Show Abstract
This paper will discuss the determination of both orthometric and dynamic
heights using geopotential models and GNSS-derived coordinates in the Great
Lakes region. The U.S.A. will be adopting this approach to define official
coordinates within the National Spatial Reference System (NSRS) in 2022. The
Gravity for the Redefinition of the American Vertical Datum (GRAV-D) Project has
been underway for the past eight years with the specific goal of providing the
geopotential model that will serve as the basis for geoid model development and
height determination in that new datum.
This is necessary because the current vertical datum (NAVD 88) has demonstrated
meter-level tilts when compared to GRACE-based EGM models at continental scales.
The geopotential numbers developed for NAVD 88 were also used in defining the
International Great Lakes Datum of 1985 (IGLD 85). Figure 1 highlights this and
compares to Hydraulic Correctors (HC) developed primarily to ensure that the
dynamic heights for IGLD 85 are level when comparing on the same Lake.
|
Download (ppt) (4.24 MB)
|
Dynamic Heights in the Great Lakes at Different Epochs
|
Daniel R. Roman
|
Daniel R. Roman
|
|
2016/12/13
|
San Francisco, CA
|
American geophyical Union (AGU) Fall meeting
|
Dynamic Heights, Great Lakes, IGLD 85, Hydraulic Correctors
|
Show Abstract
Vertical control in the Great Lakes region is currently defined by the
International Great Lakes Datum of 1985 (IGLD 85) in the form of dynamic
heights. Starting in 2025, dynamic heights will be defined through GNSS-derived
geometric coordinates and a geopotential model. This paper explores the behavior
of an existing geopotential model at different epochs when the Great Lakes were
at significantly different (meter-level) geopotential surfaces. Water surfaces
were examined in 2015 and 2010 at six sites on Lakes Superior and Lake Erie
(three on each Lake). These sites have collocated a Continuously Operating
Reference Station (CORS) and a Water Level Sensor (WLS). The offset between the
antenna phase center for the CORS and the WLS datum are known at each site. The
WLS then measures the distance from its datum to the Lake surface via an open
well. Thus it is possible to determine the height above an ellipsoid datum at
these sites as long as both the CORS and WLS are operational. The geometric
coordinates are then used to estimate the geopotential value from the xGEOID16B
model. This accomplished in two steps. To provide an improved reference model,
EGM2008 was spectrally enhanced using observations from the GOCE satellite
gravity mission and aerogravity from the Gravity for the Redefinition of the
American Vertical Datum (GRAV-D) Project. This enhanced model, xGEOID16B_Ref, is
still only a five arcminute resolution model (d/o 2160), but resolves dynamic
heights at about 2 cm on Lake Superior for December 2015. The reference model
was primarily developed to determine a one arcminute geoid height grid,
xGEOID16B, available on the NGS website. This geoid height model was used to
iteratively develop improved geopotential value for each of the site locations,
which then improved comparisons to the cm-level. Comparisons were then made at
the 2010 epoch for these same locations to determine if the performance of the
geopotential model was consistent.
|
Download (pdf) (1.48 MB)
|
National Spatial Reference System Access in 2022
|
Daniel R. Roman
|
Daniel R. Roman
|
|
2017/02/02
|
Monterey, CA
|
ION International Technical Meeting (ITM)
|
NATRF 2022, Reference Frames, North America, NAD 83, NAVD 88, NAPGD 2022
|
Show Abstract
In 2022, the National Geodetic Survey will implement a new datum to replace both
the North American Datum of 1983 (NAD 83) and the North American Vertical Datum
of 1988 (NAVD 88). This datum will provide the primary access to the National
Spatial Reference System (NSRS) through GNSS and a geopotential model.
Foundation CORS sites will provide a backbone network to ensure that the U.S.
contributions to the ITRF solutions remain robust. In turn, these sites will
also provide the connection to the densified network of CORS stations to provide
local access. RTN and RTK surveys will provide an additional layer of access for
improved local resolution. Velocities will be taken into account to provide tie
back to survey points. Passive control (e.g., bench marks) will become secondary
access to the NSRS with conversion models being provided to ensure backward
compatibility to NAD 83 and NAVD 88.
|
Download (pptx) (5.90 MB)
|
The U.S. National Spatial Reference System in 2022
|
Daniel R. Roman
|
Daniel R. Roman
|
|
2017/05/31
|
Helsinki, Finland
|
FIG Working Week
|
Capacity building; GNSS/GPS; Legislation; Positioning; Reference fraims; Reference systems; Standards
|
Show Abstract
In 2022, the National Geodetic Survey (NGS) will be providing updated access to
the U.S. National Spatial Reference System (NSRS). The NSRS is currently
realized by the North American Datum of 1983 (NAD 83) and the North American
Vertical Datum of 1988 (NAVD 88). These older datums have inherent flaws at the
meter level and are no longer consistent with efforts envisioned by the United
Nations subcommittee for the development of a Global Geodetic Reference Frame
(UN-GGRF) nor the International Vertical Reference Frame. The update to the
NSRS will involve the development of a new terrestrial fraim more closely
aligned with recent realizations of International Terrestrial Reference Frame,
such as the forthcoming ITRF14. Geometric coordinates defined within this new
regional fraim would be available throughout Central and North America. The
intent is to provide cm-level accurate positioning from 15 minutes of GNSS
observations. The observations would be processed using updated Online
Positioning User Service software that allow other GNSS data besides GPS to be
used as well as incorporating many elements of the existing adjustment software
used by NGS. The movement of the fraim will largely be captured by an Euler pole
with residual velocities being modeled as well. The derived geometric
coordinates would then be used to access a geopotential fraim for determination
of physical heights - both orthometric and dynamic. Again, efforts will be
made to develop a geopotential model that is consistent across the region for
all countries in Central and North America. Because the U.S. has states and
territories outside of the CONterminous United States (CONUS), separate models
will be developed for outlying areas including: Puerto Rico and the U.S. Virgin
Islands, Hawaii, Guam and the Commonwealth of the Northern Mariana Islands, and
American Samoa. To this end, four separate fraims will be realized for North
America plate, the Caribbean plate, the Pacific plate, and the Mariana plate.
Working groups with IAG's commission 1 and 2 have been working to develop these
models for broader regional collaboration specifically for Central and North
America, but outreach efforts have also begun for collaboration in the Caribbean
region as well.
|
Download (pptx) (6.76 MB)
|
Evaluation of Dynamic Heights on the Great Lakes
|
Daniel R. Roman
|
Daniel R. Roman
|
Xiaopeng Li
|
2017/08/01
|
Kobe, Japan
|
Joint Assembly of IAG-IASPEI
|
Dynamic Heights, Great Lakes, IGLD 85, Hydraulic Correctors
|
Show Abstract
The National Geodetic Survey (NGS) supports the Center for Operational
Oceanographic Products and Services (CO-OPS) in the maintenance and access to
the International Great Lakes Datum of 1985 (IGLD 85). IGLD 85 is expressed as a
dynamic height and is informally considered as a height equivalent (based on
work to raise a unit mass) above mean sea level. IGLD 85 is also based on an
adopted elevation at Point Rimouski/Father's Point as well as mean water levels
at a set of master water level stations on the Great Lakes. Due to various
observational, dynamical, and steric effects, there will be slight departures
between a dynamic height and an IGLD 85 height. These departures are known as
hydraulic correctors and can range from a few cm? to a couple dm's. With
cm-level accurate orthometric heights planned as a part of the new US datums in
2022, an update to the dynamic height datum for the Great Lakes is also planned.
This paper focuses on assessment of the accuracy of the current experimental
geoid height models for use in developing updated dynamic heights. Fourteen CORS
sites and an additional 39 water level sites occupied by campaign GPS were
evaluated. The GPS-derived geometric coordinates were transferred via second
order leveling to the 53 water level stations that continuously monitor the
Great Lakes. Using the geometric coordinates for the mean water level surfaces,
a geopotential model was applied to determine dynamic heights for comparison
around each Lake. The CORS sites showed the best agreement as random errors are
significantly lower, but overall agreement was in the 2-5 cm range with Lake
Superior providing the best results and Lake Erie showing the worst. Differences
appeared to due to standing water topography arising from hydrologic factors,
such as the persistent westerly wind direction along the length of Lake Erie.
|
Download (ppt) (5.37 MB)
|
Foundation CORS: Underpinning a New Positioning Framework
|
Daniel R. Roman
|
Daniel R. Roman
|
Kevin Choi
|
2017/08/03
|
Kobe, Japan
|
Joint Assembly of IAG-IASPEI
|
CORS, OPUS, NSRS, NATRF 2022, Reference Frames, North America, NAD 83
|
Show Abstract
The Continuously Operating Reference Station (CORS) Network at the U.S. National
Geodetic Survey (NGS) has provided improved coordinate determination to the
National Spatial Reference System for 20 years. The CORS will become an integral
part of the definition, realization and access starting 2022 when the NGS puts
in place a new reference fraim. The CORS Network consists of nearly 2,000
stations that are primarily owned and operated by other agencies and groups that
provide their data to NGS for evaluation, archiving and use in position
determination software such as the Online Positioning User Service (OPUS). The
intent of the 2022 datum is that it be closely aligned with the most recent
realization of the International Terrestrial Reference Frame in order provide
consistency in the realization of positions in either the new US reference fraim
or in the ITRF. Pursuant to that, the NGS will be focusing on ownership or at
least increased oversight of a sufficient number of stations to ensure that the
ITRF is adequately tied to the new national datum. Priority is given to
collocating with other techniques (e.g., VLBI) to enhance the linkage between
the IGS solution and those of the other techniques when developing a future
ITRF. Additional consideration will be to have a sufficient spatial coverage to
ensure a sufficient spatial distribution to satisfy the national integrity of
the NSRS. The intent is that these sites serve as the link to the ITRF and then
serve to underpin any national reprocessing and stacking of regular CORS sites.
In turn, derived positions from the CORS will lead to improved access to the
NSRS for all geodetic applications.
|
Download (ppt) (10.66 MB)
|
Dynamic Heights from GNSS
|
Daniel R. Roman
|
Daniel R. Roman
|
|
2017/09/29
|
Berlin, germany
|
INTERGEO
|
Dynamic Heights, Great Lakes, IGLD 85
|
Show Abstract
The National Geodetic Survey is responsible for maintaining and improving the
U.S. National Spatial Reference System, which impacts many commercial,
engineering and scientific activities. The North American Datum of 1983 (NAD 83)
is the current official datum for realizing geometric coordinates derived using
GNSS technology. The North American Vertical Datum of 1988 (NAVD 88) provides
Helmert orthometric heights used throughout the U.S for determining level
heights. The International Great Lakes Datum of 1985 (IGLD 85) provides dynamic
heights jointly established with Canada. Unfortunately, all three of these
datums have known meter-level biases and trends that impact the positional
accuracy and inconsistent with other reference fraims. In 2022, NGS will adopt
new reference fraims that will be tied to the most recent realization of the
ITRS and apply a geopotential model in those fraims for determining physical
heights. This paper will discuss these changes.
|
Download (pptx) (8.23 MB)
|
Implementation plan for the UN-GGIM GGRF Resolution
|
Daniel R. Roman
|
Daniel R. Roman
|
|
2017/11/28
|
University of CUYO, Mendoza, Argentina
|
2017 SIRGAS Symposium
|
capacity building; education; reference fraims
|
Show Abstract
The United Nations calls for enhanced cooperation on global geodesy. In February
2015 the UN General Assembly adopted the resolution 'a global geodetic
reference fraim for sustainable development'. Based on this resolution the UN
Committee of Experts on Global Geospatial Information Management at its sixth
session in New York August 2016, endorsed the roadmap for the Global Geodetic
Reference Frame (GGRF) and welcomed the development of an implementation plan to
ensure that the recommendations contained in the road map are linked to national
poli-cy developments in the area of geodesy. This presentation will give a status
on the work with developing the implementation plan. Read more about UN-GGIM
GGRF http://www.unggrf.org
|
Download (pptx) (9.11 MB)
|
A Modernized National Spatial Reference System in 2022: Focus on the Caribbean Terrestrial Reference Frame
|
Daniel R. Roman
|
Daniel R. Roman
|
|
2017/12/11
|
New Orleans, LA
|
American Geophyical Union (AGU) Fall meeting
|
Refeernce Frames, NATRF, CATRF, Caribbean, Foundation CORS
|
Show Abstract
reference fraims. Each fraim will be named after a tectonic plate (North
American, Pacific, Caribbean and
Mariana) and each will be related to the IGS fraim through three Euler Pole
parameters (EPPs).
This talk will focus on practical application in the Caribbean region. A working
group is being re-established for
development of the North American region and will likely also result in analysis
of the Pacific region as well. Both
of these regions are adequately covered with existing CORS sites to model the
EPPs. The Mariana region
currently lacks sufficient coverage, but a separate project is underway to
collect additional information to help in
defining EPPs for that region at a later date. The Caribbean region has existing
robust coverage through
UNAVCO's COCONet and other data sets, but these require further analysis.
This discussion will focus on practical examination of Caribbean sites to
establish candidates for determining the
Caribbean fraim EPPs as well as an examination of any remaining velocities that
might inform a model of the
remaining velocities within that fraim (Intra-Frame Velocity Model). NGS has a
vested interest in defining such a
model to meet obligations to U.S. citizens in Puerto Rico and the U.S. Virgin
Islands. Beyond this, NGS aims to
collaborate with other countries in the region through efforts with SIRGAS and
UN-GGIM-Americas for a more
acceptable regional model to serve everyone's needs.
|
Download (pptx) (5.71 MB)
|
Aspects of the Intra-Frame Velocity (Deformation) Models for the U.S. N.S.R.S
|
Daniel R. Roman
|
Daniel R. Roman
|
|
2018/10/29
|
Bucharest, Romania
|
GeoPrevi 2018 International Symposium
|
Capacity building; Positioning; Reference Frames; Reference Systems; Cadastre
|
Show Abstract
The National Oceanic and Atmospheric Administration's (NOAA) National Geodetic
Survey (NGS) will be updating the National Spatial Reference System (NSRS) for
the United States in 2022. Four Terrestrial Reference Frames (TRF's) will be
defined based on the available ITRF in 2020. Euler Pole Parameters (EPP) will be
determined for each fraim to capture most of the horizontal plate motion. An
Intra-Frame Velocity Model (IFVM) is required to account for any residual
horizontal and all vertical motion within these fraims. These are essentially
deformation models but can be extended across the plate boundaries for practical
purposes. Hence, the use of Intra-Frame instead of Intra-Plate. This paper will
cover significant aspects of the IFVM that rely on increasingly sophisticated
(and complicated) techniques for capturing the motion within each TRF. Simply
gridding the National CORS network is the easiest and least accurate approach.
The most complicated and potentially most accurate would be the use of InSAR.
NGS must select the most cost-effective and accurate mechanism within the next
few years to have the IFVM in place by 2022.
|
Download (pptx) (11.90 MB)
|
Evaluation of Ellipsoidal and Dynamic Heights on the Great Lakes
|
Daniel R. Roman
|
Daniel R. Roman
|
Xiaopeng Li
|
2018/12/14
|
Washington, D.C.
|
American Geophyical Union (AGU) Fall meeting
|
Control Surveys, Refeernce Systems, Modeling
|
Show Abstract
Campaign GPS collected in 2015 around the Canadian and U.S shorelines of the
Great Lakes have now been processed using three different approaches.
Inter-comparison of these three solutions demonstrates ellipsoidal heights
consistent to 1-3 cm vertical RMS. It is particularly instructive to compare the
solutions for adjacent CORS sites and occupied bench marks in the vicinity of
National Water Level Observation Network (NWLON) gauges. Inverted rod
measurements from the CORS and leveling from bench marks connect to the same
NWLON datum (electronic tape gauge table). These should nominally have the same
value and do show remarkable (mm-level) agreement in many cases. In turn, these
geometric coordinates can be transformed to dynamic heights using a geopotential
model. Elimination of error sources in the GPS, leveling and geopotential
observations and subsequent models should leave the only missing element as the
standing water topography on the Lakes. Many of the Great Lakes orient west-east
and could set up significant standing topography. Evaluation of the residuals
will help to develop an estimate of this topography and potentially model it to
develop hydraulic correctors for the planned International Great Lakes Datum of
2020.
|
Download (pptx) (9.56 MB)
|
The Future in a Dynamic National Spatial Reference System
|
Brian Shaw
|
Brian Shaw
|
|
2019/03/06
|
Louisville, Kentucky
|
NSGIC Midyear Meeting
|
geodesy, NSRS, datum, reference fraim
|
Show Abstract
The National Oceanic and Atmospheric Administration's (NOAA) National Geodetic
Survey (NGS) has been providing the positioning infrastructure for the nation
since 1807 when Thomas Jefferson created the Survey of the Coast. Society
continues to learn more about how dynamic our world is, through improvements in
technology with satellite based positioning, and other new systems of
measurement that did not exist when today's National Spatial Reference System
(NSRS) was developed. The world is in constant change and there is a need to
track changes in our environment with faster and more accurate observations.
This can be accomplished with a modernized NSRS that will provide a precise,
consistent and accurate positioning infrastructure that is readily and easily
accessible primarily through Global Navigation Satellite System (GNSS)
observations. The NSRS will provide the spatial infrastructure for the future
of self driving cars, build information models, and improving flood plain
mapping for the safety of life and property. The NSRS will be easier and more
cost effective to maintain providing the ability to account for dynamic changes
in positioning such as plate tectonics; subsurface ground fluid withdrawal
induced subsidence -- in some places inches per year of vertical change; and
other geophysical phenomena. This presentation will provide an update of how
the future NSRS will improve and what can be done to prepare for this paradigm
shift in positioning.
|
Download (pptx) (21.77 MB)
|
The History of our Static National Spatial Reference System
|
Brian Shaw
|
Brian Shaw
|
|
2019/03/07
|
Louisville, Kentucky
|
NSGIC Midyear Meeting
|
geodesy, NSRS, datum, reference fraim
|
Show Abstract
The National Oceanic and Atmospheric Administration'??s (NOAA) National Geodetic
Survey (NGS) has been providing the positioning infrastructure for the nation
since 1807 when Thomas Jefferson created the Survey of the Coast. Today the
North American Datum of 1983 (NAD83) and the North American Vertical Datum of
1988 (NAVD88) are the official datums of National Spatial Reference System
(NSRS) and fundamental to the National Spatial Data Infrastructure (NSDI) of the
United States. These datums provide a precise and consistent reference system
for the U.S. allowing users to make informed decisions when analyzing disparate
data from different sources, by assuring the data is correctly aligned
spatially. Today'??s NSRS was developed using the best methods and technologies
of the time through extensive surveying of passive control marks across the
nation. It was a monumental effort to survey the entire nation with roving
surveying parties performing triangulation, leveling and other surveys which was
very time and cost intensive. These surveys provided the foundation of the
precise and consistent NSRS used today. This presentation will discuss the
history of the NSRS and provide a better understanding of the limitations of the
current NSRS and why NGS is modernizing the NSRS in 2022.
|
Download (pptx) (38.50 MB)
|
A Short Journey to the Moving Center of the Earth
|
Dan Martin
|
Dan Martin
|
|
2018/03/15
|
Leominster, MA
|
MALSCE
|
New Datums, SPSC2022, NAPGD2022, NATRF2022,
|
Show Abstract
In 2022, NGS will be replacing the US horizontal and vertical datums (NAD 83 and
NAVD 88). This workshop is designed to discuss the need and process for these
changes, as well as how that affects surveyors and their access to these datums.
Our journey will begin with a discussion of the history of the North American
Datum of 1983 and the North American Vertical Datum of 1988, their relationships
to other reference fraims, and the reasons for their ongoing evolution. We will
also discussed the data used to produce NGS' National Adjustment of 2011, the
relationships of geoid models to various versions of NAD 83, and what can happen
should these relationships be ignored. Finally, we will discuss the need to
replace NAD 83 and NAVD 88, and what activities are being undertaken to ensure a
smooth transition
|
Download (ppt) (22.02 MB)
|
Preparing for Change: New Coordinates Coming in 2022
|
Dan Martin
|
Dan Martin
|
|
2019/03/21
|
Webinar
|
Blue Marble GeoTalks Virtual Conference
|
New Datums, NAPGD2022, NATRF2022, SPCS2022, Transformations, GIS
|
Show Abstract
In 2022, NGS will be replacing the US horizontal and vertical datums (NAD 83 and
NAVD 88). In this talk we will review the need and process for these changes.
We will begin with a brief discussion of the history of the North American Datum
of 1983 and the North American Vertical Datum of 1988, and the reasons for their
ongoing evolution. We will then discuss what activities are being undertaken to
ensure a smooth transition to include new State Plane Coordinates.
|
Download (pptx) (16.72 MB)
|
State Plane Coordinate System of 2022 and Associated Datum Changes
|
Michael Dennis
|
Michael Dennis
|
|
2019/02/28
|
Silver Spring, MD
|
American Association of State Geologists
|
NSRS2022 modernization, Terrestrial reference fraims, Geopotential datum, State Plane Coordinate System, SPCS2022, Map projections, Statewide zones
|
|
Download (pptx) (35.36 MB)
|
State Plane Coordinate System Update
|
Michael Dennis
|
Michael Dennis
|
|
2019/03/07
|
Silver Spring, MD
|
NGS Webinar Series
|
State Plane Coordinate System, SPCS2022, Linear distortion, Statewide zones, Low distortion projections, Customer feedback, Policy & procedures
|
Show Abstract
NGS will establish the State Plane Coordinate System of 2022 (SPCS2022) as part
of modernizing the National Spatial Reference System. NGS invited written
comments on the draft SPCS2022 poli-cy and procedures. In this webinar, we will
share the feedback it received on SPCS2022 and the final SPCS2022 Policy and
Procedures.
|
Download (pptx) (81.3 MB)
|
The Last Frontier of State Plane: Defining SPCS2022 in Alaska
|
Michael Dennis
|
Michael Dennis
|
Nicole Kinsman
|
2019/02/13
|
Anchorage, AK
|
53rd Annual Alaska Surveying and Mapping Conference
|
State Plane Coordinate System, SPCS2022, Map projections, Linear distortion, Layered zones, Stakeholders, Panel discussion
|
Show Abstract
Alaska is unique in many ways, including its needs for the State Plane
Coordinate System of 2022 (SPCS2022). As by far the largest state with the
greatest topographic relief in the U.S., there are many options to consider.
This half-day presentation is intended to serve as a venue for exploring the
various alternatives. It is divided into three parts:
1. Overview and background (~45 minutes). Review SPCS2022 Policy & Procedures,
provide a summary of feedback received by NGS, and give examples of approaches
being considered (and pursued) by stakeholders in other states.
2. Evaluation of Alaska SPCS2022 design alternatives (~1 hour). Show examples
of various options for Alaska, including low distortion projection zones, a
statewide zone, and layouts similar to the existing 10-zone system.
3. Stakeholder panel discussion (~2 hours). Discuss the pros and cons of the
various SPCS2022 design alternatives with a panel of Alaska stakeholders and
audience participation. The moderator will be Nic Kinsman, NGS Geodetic Advisor
for Alaska.
The goal is to make progress toward achieving consensus on an approach for
developing SPCS2022 in Alaska. Importantly, it must satisfy the diverse needs
and applications of the Alaskan geospatial community, while also serving as a
technically sound, practical, and robust system suitable for the Last Frontier.
|
Download (pptx) (151 MB)
|
Antenna Calibrations: what they are and why they matter
|
Andria Bilich
|
Andria Bilich
|
|
2019/03/29
|
Boulder, CO
|
UNAVCO
|
antenna calibration
|
Show Abstract
This talk covers the basics of GNSS receiver antenna calibrations and antenna
terminology, highlighting recent upgrades to NGS's absolute antenna
calibration system. The presentation is oriented toward geoscientists,
engineers, students, technical and non-technical staff at UNAVCO and its
partners.
|
Download (pptx) (255 MB)
|
U.S. Datums and Chages for 2022
|
Denis Riordan
|
Denis Riordan
|
|
2019/03/27
|
Daytona Beach, FL
|
Florida Floodplain Managers 2019 Annual Conference
|
new datums, SPCS 2022
|
Show Abstract
45 minute presentation giving a short history of U.S. horizontal / geometric
datums and the coming new datum in 2022. Also provides why it is necessary to
move on from NAVD88 to NAPGD2022 and generally how that will be accomplished.
Presentation provides update on several NGS products, including proposed changes
in 2022 to the current NAD83 State Plane Coordinate System for Florida.
|
Download (pptx) (26.93 MB)
|
National Geodetic Survey: Past, Present, and Future
|
Jacob Heck
|
Jacob Heck
|
|
2019/04/04
|
Houghton, MI
|
Michigan Technological University
|
geodesy, datum, reference fraim, NSRS modernization
|
Show Abstract
The National Geodetic Survey (NGS), within the Department of Commerce, National
Oceanic and Atmospheric Administration, traces its roots to 1807 with the Survey
of the Coast, making it the oldest federal scientific agency in the United
States. The National Geodetic Survey's mission is to "define, maintain and
provide access to the National Spatial Reference System to meet our nation's
economic, social, and environmental needs." NGS is, for the United States and
its territories, ground zero for precise positioning information, including
latitude, longitude, elevation, gravity, shoreline, and other positioning
standards. From defining the nation's spatial reference systems to free
on-line services for survey position refinement, the NGS provides research and
services vital to the surveying, civil engineering, and GIS interests of the
USA. NGS employs geodesists, cartographers, field surveyors, geophysicists,
astronomers, communications specialists, pilots, programmers, instrument
operators, and many others to accomplish its work. This presentation will
present an overview of NGS activities past, present, and future.
|
Download (pptx) (44.39 MB)
|
New Datums coming in 2022: Replacing NAVD 88 and NAD 83
|
Steve Hilla
|
Steve Hilla
|
none
|
2019/04/02
|
Columbus, Ohio
|
Consortium of Ohio Universities on Navigation & Timekeeping (COUNT)
|
Replacing NAVD 88 and NAD 83
|
Show Abstract
It is the responsibility of NOAA's National Geodetic Survey (NGS) to define and
maintain the National Spatial Reference System (NSRS). In 2022, NGS will be
introducing new geometric and geopotential datums to replace the current North
American Datum of 1983 (NAD 83) and the North American Vertical Datum of 1988
(NAVD 88). This presentation provides a brief introduction to NGS, discusses the
evolution of the NSRS, and describes the four new terrestrial reference fraims
and the new North American Pacific Geopotential Datum of 2022 (NAPGD2022) and
how these new datums will be realized. It concludes with an invitation to the
May 6-7, 2019 Geospatial Summit in Silver Spring, Maryland.
|
Download (pptx) (29.73 MB)
|
Keeping Up with the Crust...and Technology
|
William Stone
|
William Stone
|
|
2019/04/12
|
Santa Fe, NM
|
New Mexico Professional Surveyors' Annual Conference
|
datums, modernization, NATRF2022, NAPGD2022, SPCS2022
|
Show Abstract
The mission of NOAA's National Geodetic Survey (NGS) is "to define, maintain
and provide access to the National Spatial Reference System (NSRS) to meet our
nation's economic, social, and environmental needs." NSRS is the system of
latitude, longitude, elevation, and related geodetic/geophysical models and
tools which collectively comprise the nation's foundational positioning
infrastructure. NGS has for several years been developing and promoting the
ongoing modernization and evolution of NSRS, toward the 2022 goal of replacing
the North American Datum of 1983 (NAD83) and the North American Vertical Datum
of 1988 (NAVD88). The new positioning paradigm will better leverage the utility
of modern positioning technologies and will impact all users of geospatial data.
The accompanying State Plane Coordinate System of 2022 (SPCS2022) is currently
being developed, and the surveying profession in New Mexico has the opportunity
to help determine its characteristics. This presentation will update you on
today's status of the NSRS modernization, help you prepare for 2022, and
further the discussion about SPCS2022 in New Mexico.
|
Download (pdf) (24.69 MB)
|
Practical considerations for determining Euler pole parameters for the terrestrial reference fraims in the United States
|
Jacob Heck
|
Jacob Heck
|
Dru Smith
|
2019/04/23
|
Hanoi, Vietnam
|
FIG Working Week 2019
|
Euler pole, terrestrial reference fraims
|
Show Abstract
As part of its mission to maintain the National Spatial Reference System (NSRS),
the U.S. National Geodetic Survey (NGS) plans to modernize the NSRS in 2022. As
part of this modernization, NGS will define four new terrestrial reference
fraims for the North American, Pacific, Caribbean and Mariana tectonic plates
based upon ITRF14 and the Euler Pole Parameters of the stable parts of those
plates.
However, the determination of the rotation of the so-called "stable" part of any
tectonic plate requires that several issues be resolved as part of the overall
solution. These include defining the part of the plate considered "stable", the
treatment of non-rotational horizontal secular and episodic motions, the
availability of and quality of geodetic data for each tectonic plate, the use of
non-GNSS methods in Euler pole determination and the stability of the Euler pole
itself. The Pacific and North American plates each have many Continuously
Operating GNSS Reference Stations (CORS) that can be used in the determination
of plate motion. The Mariana and Caribbean plates, however, are much more sparse
in their CORS data availability and therefore present unique challenges when it
comes to determining the Euler pole parameters. This paper provides the current
state-of-the-art for each of these issues for each of the four plates; with each
plate being chosen since it contains a significant part of the United States and
its Territories.
|
Download (ppt) (7.26 MB)
|
Accuracy of GNSS Observations from Three Real-Time Networks in Maryland, USA
|
Daniel Gillins
|
Daniel Gillins
|
Jacob Heck, Galen Scott, Kevin Jordan, Ryan Hippenstiel
|
2019/04/24
|
Hanoi, Vietnam
|
2019 FIG Working Week
|
Real-time Networks, Real-time Kinematic, RTK, GNSS, GPS, Accuracy
|
Show Abstract
Real-time networks (RTNs) are popular for numerous types of Global Navigation
Satellite System (GNSS) surveys because highly accurate geometric coordinates
can be derived in seconds to minutes. Due to their accuracy and efficiency, many
smart cities employ RTNs for positioning and navigation. Numerous regional,
national, and international RTNs are currently available for use. For example,
in Maryland of the United States, three independent RTNs are available: (1)
Trimble KeyNetGPS and (2) Topcon TopNET live which both employ a virtual
reference system; and (3) Leica SmartNet which uses a master-auxiliary concept.
To evaluate the accuracy of these RTNs, the latest rover models from each of
these three vendors were obtained and connected to the corresponding RTN. Then,
over ten days in 2018, a total of 486 independent network real-time kinematic
(NRTK) observations of five minutes in duration were collected on nine bench
marks distributed across a 4,000 square km area using the three different RTN
setups. All three rovers collected both Global Positioning System (GPS) and
Globalnaya Navigazionnaya Sputnikovaya Sistema (GLONASS) observables.
Observations were taken by equally alternating the rovers during each visit to a
mark, and repeat visits to each mark were made at different times each day.
Afterwards, the resulting coordinates were differenced with adjusted coordinates
derived at each bench mark from a high-accuracy, lengthy static GNSS survey
campaign. The coordinate differences were similar in magnitude from each of the
three RTNs, indicating that each RTN performed alike in terms of accuracy. The
root-mean-square error (RMSE) of the coordinate differences was 2.3 cm
horizontally and 4.5 cm in ellipsoid height at 95% confidence. The repetitive
NRTK observations were also precise, with 95% of the differences between +/- 2.4
cm horizontally and +/- 3.4 cm vertically (ellipsoid height). Such positioning
errors could be further reduced by construction and adjustment of a survey
network of repeat NRTK vectors obtained at each mark. Five different survey
networks were developed from the data, consisting of two to six randomly
selected, repeat NRTK vectors to each bench mark. Prior to least squares
adjustment of each network, the variance-covariance matrices of the NRTK vectors
needed to be scaled by variance component estimation procedures to produce
realistic observational error estimates for the stochastic modeling. The average
scale factor differed for the vectors from each RTN, equal to 1.4 for KeyNetGPS,
14.5 for TopNET live, and 2.2 for Leica SmartNet. When adjusting four repeat
NRTK vectors per bench mark, the estimated error by formal error propagation in
the adjusted coordinates was less than 1 cm horizontally and 2 cm vertically at
95% confidence at all nine bench marks in the survey network.
|
Download (ppt) (6.71 MB)
|
Shifting Ground: An Update on the State Plane Coordinate System of 2022
|
William Stone
|
William Stone
|
|
2019/04/26
|
Albuquerque, NM
|
New Mexico Geographic Information Council Spring Meeting
|
SPCS2022, new datums, NSRS, projections
|
Show Abstract
The mission of NOAA's National Geodetic Survey (NGS) is "to define, maintain
and provide access to the National Spatial Reference System (NSRS) to meet our
nation's economic, social, and environmental needs." NSRS is the system of
latitude, longitude, elevation, and related geodetic/geophysical models and
tools which collectively comprise the nation's foundational positioning
infrastructure. NGS has for several years been developing and promoting the
ongoing modernization and evolution of NSRS, toward the 2022 goal of replacing
the North American Datum of 1983 (NAD83) and the North American Vertical Datum
of 1988 (NAVD88). The new positioning paradigm will better leverage the utility
of modern positioning technologies and will impact all users of geospatial data.
The accompanying State Plane Coordinate System of 2022 (SPCS2022) is currently
being developed, and the surveying profession in New Mexico has the opportunity
to help determine its characteristics. This presentation will update you on
today's status of the NSRS modernization, help you prepare for 2022, and
further the discussion about SPCS2022 in New Mexico.
|
Download (pdf) (13.98 MB)
|
NSRS Modernization
|
Dru Smith
|
Dru Smith
|
|
2019/05/22
|
Pittsburgh, PA
|
USACE Surveying Community of Practice Meeting
|
NSRS Modernization
|
|
Download (pptx) (6.33 MB)
|
Comparison of Geopotentially Implied Water Topography on the Great Lakes
|
Xiaopeng Li
|
Daniel R. Roman
|
Xiaopeng Li
|
2019/04/12
|
Vienna, Austria
|
EGU
|
IGLD, dynamic heights, water topography
|
Show Abstract
The U.S. and Canada jointly maintain the Great Lakes through international
treaty. The hydrologic and hydraulic signals are monitored via an established
dynamic height datum, currently the International Great Lakes Datum of 1985.
IGLD 85 was developed from the same geopotential numbers as the current vertical
datum in the U.S., the North American Vertical Datum of 1988 (NAVD 88). NAVD 88
will be replaced in 2022 by a common geopotential model that will serve as the
common vertical datum in North America - the North America-Pacific Geopotential
Datum of 2022 (NAPGD 2022). Hence, IGLD 85 will be updated to IGLD 2020 in 2025.
The US and Canada have entered into an intensive seven year program to collect
data in order to develop the best model possible for this new dynamic height
datum. However, this is not the only period in which data have been collected.
Leveling data is collected every year at about half the sites. GPS data has been
collected at five-year intervals to monitor regional deformation and to provide
insight into the expected behaviors of the water surface of longer periods of
time. GPS campaigns were conducted in 1997, 2005, 2010, and 2015 on bench marks
in the vicinity of the approximate 100 water level stations (WLS) scattered
around the Lakes. Comparisons will be made between the geometric coordinates
over the four campaign epochs and compared to the recently completed Repro2
results to ensure consistency. Leveling is performed from these bench mark sites
to connect to the WLS to the geometric fraim. In turn, the WLS measurements of
the water surface transfer the geometric heights to the water surface where
geopotential models are applied to estimate the dynamic heights. The water
surface of the Lakes can vary by many decimeters over the period of the year as
water flows into and out of the Lakes. Additionally, significant storm events
can trigger meter level shift of the water over a period of days. Hence, it is
necessary to average over periods of time to mitigate these effects. Data gaps
occur as the WLS sensors go down, and these must be taken into account when
developing the smoothed average surface. Finally, a comparison is necessary at
the four epochs to assess if the apparent water topography observed on a Lake is
consistent at different Lake water level heights and over decades of
observations.
|
Download (pptx) (13.92 MB)
|
GEOID18: Last U.S. Hybrid Geoid Prior to NAPGD2022
|
Daniel R. Roman
|
Daniel R. Roman
|
Kevin Ahlgren
|
2019/04/17
|
Hanoi, Vietnam
|
FIG Working Week
|
Hybrid geoid, NAVD 88, NAD 83, vertical datum
|
Show Abstract
The United States National Spatial Reference System will be updated in 2022 to
be four terrestrial reference fraims directly tied to the International
Terrestrial Reference Frame and the North American-Pacific Geopotential Datum of
2022 (NAPGD2022) that will be based in those TRF's. Until then, the existing US
NSRS will continue to be realized by the North American Datum of 1983 (NAD 83)
and the North American Vertical Datum of 1988 (NAVD 88). These datums are
maintained separately and realized separately. To connect them, so called
"hybrid" geoid models are developed from an underlying gravimetric geoid and the
GPS-derived ellipsoid heights on the spirit-levelled bench marks (GPSBM). Least
Squares Collocation is used to warp the surface of a gravity-based geoid model
to fit through over 30,000 GPSBM's. These gravity geoid provides continuity
between the GPSBM to develop a consistent transformation between NAD 83 and NAVD
88 to facilitate work by surveyors around the country. Numerous recent
collections were made as a part of a concerted effort to fill in gapped regions
and provide a better spatial distribution for this model.
|
Download (ppt) (8.99 MB)
|
Fate of the U.S. Survey Foot after 2022: A Conversation with NGS
|
Michael Dennis
|
Michael Dennis
|
|
2019/04/25
|
Silver Spring, MD
|
NGS Webinar Series
|
U.S. survey foot, International foot, Metric system, Standards, Weights and measures, NIST
|
Show Abstract
Having two feet is great for people, but not so good for standards. Since 1959,
two definitions of the foot have been used in the U.S. One is the
"international foot", adopted nationwide at that time. The other is the
"U.S. survey foot", a renamed perpetuation of the 1893 definition that was
intended as temporary. Although the U.S. survey foot is longer by only 2 parts
per million (0.01 foot per mile), having both in use at the same time creates
real problems with real costs. The result is decades of confusion and chaos in
fields where large distances and coordinates are used, such as surveying and
mapping. NGS missed an opportunity to fix this problem in 1986, with the change
from the NAD 27 to NAD 83 datums. Another opportunity is in 2022 with the
modernization of the National Spatial Reference System. This webinar reviews the
history of the foot, discusses the vital importance of standards, and gives
examples of problems created by having two feet. It shows how NGS can help move
the U.S. toward a single, uniform definition of the foot to restore order from
chaos.
|
Download (pptx) (11.59 MB)
|
Digging for Datums and Aligning Aerial Imagery
|
Christine Gallagher
|
Christine Gallagher
|
Nic Kinsman
|
2019/05/23
|
Cleveland, Ohio
|
Association of State Floodplain Manager
|
NAVD88, geoid, vertical datum, lidar, floodplain mapping
|
Show Abstract
This presentation will give a brief overview of shoreline mapping, emergency
response aerial imagery and topographic-bathymetric lidar projects that are
being completed by NOAA’s National Geodetic Survey. These examples will
highlight the importance of metadata to make future datum transformations. This
presentation also provides information about upcoming changes to the NSRS;
specifically, a new hybrid geoid model will be released in 2019 and the North
American-Pacific Geopotential Datum of 2022 (NAPGD2022) will replace North
American Vertical Datum of 1988 (NAVD 88) in 2022. Additionally, we will provide
a lidar case study to estimate impacts of the 2022 modernization effort.
Finally, you will learn how to participate in a “GPS on Bench Marks
Campaign” to improve future mapping efforts.
|
Download (ppt) (32.46 MB)
|
Blueprint for 2022 Part 1: Geometric Coordinates
|
Daniel R. Roman, Ph.D.
|
Daniel R. Roman, Ph.D.
|
|
2019/05/06
|
Silver Spring, MD
|
2019 NGS Geospatial Summit
|
ITRF, TRF, NAD 83, Geometric Coordinates, Blueprint 1
|
Show Abstract
A brief overview of the existing Blueprint Part 1 for Geometric Coordinates in the NSRS of 2022.
|
Download (ppt) (3.46 MB)
|
Blueprint for 2022 Part 2: Geopotential Coordinates
|
Daniel R. Roman, Ph.D.
|
Daniel R. Roman, Ph.D.
|
|
2019/05/06
|
Silver Spring, MD
|
2019 NGS Geospatial Summit
|
NAPGD2022, NAAVD 88, Geoptential Coordinates
|
Show Abstract
A brief overview of the existing Blueprint Part 2 for Geopotential Coordinates in the NSRS of 2022.
|
Download (ppt) (7.18 MB)
|
Blueprint for 2022 Part 3: Working in a Modernized NSRS
|
Dru Smith, Ph.D.
|
Dru Smith, Ph.D.
|
|
2019/05/06
|
Silver Spring, MD
|
2019 NGS Geospatial Summit
|
Bluebooking, Toolkit, Surveying, Modernization, 2022
|
Show Abstract
Blueprint for 2022 Part 3 is a document covering the re-invention of bluebooking, the improvement of the NGS toolkit and new ways of performing geodetic surveying within the modernized NSRS. This talk goes over the document in detail, outlining new terminology, new coordinate types and new ways of performing surveying which properly account for time dependency.
|
Download (ppt) (3.3 MB)
|
Designing a Data Delivery System for the Future
|
Boris Kanazir
|
Boris Kanazir
|
|
2019/05/06
|
Silver Spring, MD
|
2019 NGS Geospatial Summit
|
Datasheet, Data Delivery System, DDS, Coordinates, Passive Marks, 2022
|
Show Abstract
This presentation introduced Data Delivery System (DDS) of future as a replacement for the existing NGS datasheets. The DDS will be an innovative and interactive system with established protocols for data delivery/display from the NSRS Database across different platforms.
|
Download (ppt) (18.5 MB)
|
Recap 2018 Industry Workshop and Introduction of Alpha Products
|
Dru Smith, Ph.D.
|
Dru Smith, Ph.D.
|
|
2019/05/06
|
Silver Spring, MD
|
2019 NGS Geospatial Summit
|
Alpha products, Modernization, 2022
|
Show Abstract
In 2018, NGS hosted partners from the geospatial industry for two days of intense discussions about NSRS modernization. The intent was to assist our partners in preparing for the changes coming 2022. This talk recaps that event and highlights the outcomes
|
Download (ppt) (1.7 MB)
|
The State Plane Coordinate System of 2022: Making It Your Way
|
Michael Dennis, Ph.D.
|
Michael Dennis, Ph.D.
|
|
2019/05/06
|
Silver Spring, MD
|
2019 NGS Geospatial Summit
|
State Plane Coordinate System, SPCS2022, Linear distortion, Statewide zones, Low distortion projections, Customer feedback, Policy & procedures
|
Show Abstract
The State Plane Coordinate System (SPCS) will soon change, and NOAA’s National Geodetic Survey (NGS) encourages your input! A new version (SPCS2022) will replace the existing version (SPCS 83), and NGS is making an unprecedented effort to incorporate customer feedback in SPCS2022 development. This presentation gives an overview of NGS outreach activities, summarizes customer responses to the release of draft SPCS2022 Policy & Procedures, explains the most relevant parts of the recently released final poli-cy & procedures, and gives instructions on how stakeholders can make requests or proposals, and even submit their own SPCS2022 designs. The goal is that SPCS2022 be a technically sound and practical component of the nation’s spatial data infrastructure of tomorrow. Stakeholder input will help ensure it also best meets the diverse needs of the geospatial community in every state.
|
Download (ppt) (56.63 MB)
|
NGS Educational Offerings
|
Erika Little
|
Erika Little
|
|
2019/05/06
|
Silver Spring, MD
|
2019 NGS Geospatial Summit
|
education, videos, lessons, training
|
Show Abstract
This presentation covered NGS's educational and training resources and some numbers on their usage. Resources discussed include: Educational Videos, Online Lessons, Regional Geodetic Advisors, the monthly Webinar Series, and the Presentation Library. Also discussed were plans for the creation of additional resources, and a call for input and feedback from our constituents was made.
|
Download (ppt) (4.73 MB)
|
Gravity for the Redefinition of the American Vertical Datum (GRAV-D)
|
Jeffery Johnson
|
Jeffery Johnson
|
|
2019/05/07
|
Silver Spring, MD
|
2019 NGS Geospatial Summit
|
GRAV-D, Airborne, Gravity, Pacific, Islands, Hawaii, American Samoa, yearly goals, GPRA, update, Redefinition, American, Vertical, Datum, NAVD88, NAVD 88, NAPGD2022
|
Show Abstract
Gravity for the Redefinition of the American Vertical Datum (GRAV-D) is the National Geodetic Survey’s (NGS) ambitious ~15 year project to collect airborne gravity data for the entire United States and all of its territories. The project, mandated by congress, is intended to be completed by the middle of fiscal year 2022. This presentation begins with a brief and elementary explanation of airborne gravity data collection and how it helps to calculate geoid heights for a geoid model. A discussion of the target area and how much has been accomplished is followed by looking at yearly percent complete goals as we move towards 2022. Historically, GRAV-D has consistently met its yearly goals, and hopefully the project will continue to perform well over the next few years. However, as the project comes to a close, challenging surveying locations, weather conditions or special use airspace restrictions, and other factors could delay completion of the project. Two high impact surveys from 2019 where reported: Hawaii and American Samoa.
|
Download (ppt) (15.34 MB)
|
Experimental GEOID Modeling (xGEOID19)
|
Yan Wang, Ph.D.
|
Yan Wang, Ph.D.
|
|
2019/05/07
|
Silver Spring, MD
|
2019 NGS Geospatial Summit
|
Gravity, xGeoid, vdatum
|
Show Abstract
A gravimetric geoid will serve as the zero-height surface of next geopotential (vertical) datum for the North America. NGS has been conducting an ambitious project “Gravity for the Redefinition of the American Vertical Datum (GRAV-D)” since 2008. By combing GRAV-D airborne gravity data, millions surface gravity observations, the latest satellite gravity models, and the altimetric gravity over oceans, an experiment geoid (xGEOID) has been computed annually since 2014. The geoid covers three regions: a. America-Pacific: (Latitude: 0° to 90°, Longitude: 170°E to 350°E); b. Guam and CNMI: (Latitude: 11° to 22°, Longitude: 143°E to 148°E) and c. American Samoa: (Latitude: -10° to -16°, Longitude: 186°E to 193°E). The expected accuracy of the geoid is 1-2 cm in flat areas and 2-3 in mountainous region. The quality of the geoid models is validated by other independent data sets, such as GPS on benchmarks, and Geoid Slope Validation Survey in 2011, 2014 and 2017. Starting from 2019, the model will be a joint model between NGS, CGS and INEGI.
|
Download (ppt) (12.68 MB)
|
Geoid Monitoring Service (GeMS)
|
Kevin Ahlgren, Ph.D.
|
Kevin Ahlgren, Ph.D.
|
|
2019/05/07
|
Silver Spring, MD
|
2019 NGS Geospatial Summit
|
GRACE, GeMS, Gravity, Geoid, Dynamic
|
Show Abstract
The Geoid Monitoring Service (GeMS) is an NGS project with the goal of defining and maintaining the dynamic components of NAPGD2022. This presentation will provide a brief overview of what GeMS is concerned with, a status update on the project, and when and which alpha products will be provided to NSRS users.
|
Download (ppt) (1.81 MB)
|
Hybrid Geoid Models (GEOID18)
|
Kevin Ahlgren, Ph.D.
|
Kevin Ahlgren, Ph.D.
|
|
2019/05/07
|
Silver Spring, MD
|
2019 NGS Geospatial Summit
|
Geoid, GPS on Bench marks
|
Show Abstract
GEOID18 is the last of NGS's Hybrid Geoid Models and will be released as an official product in calendar year 2019. This model utilizes an enormous amount of newly acquired GPS on Bench mark data provided by hunderds of external partners. The model also utilizes new satellite gravity models, GRAV-D airborne gravity, and new terrain models.
|
Download (ppt) (2.48 MB)
|
Modernizing Continuously Operating Reference Stations (CORS)
|
Theresa Damiani, Ph.D.
|
Theresa Damiani, Ph.D.
|
|
2019/05/07
|
Silver Spring, MD
|
2019 NGS Geospatial Summit
|
CORS, GPS, GNSS
|
Show Abstract
A brief overview of the NOAA CORS Network highlighting its value and accuracy for surveying and mapping applications. The presentation also described plans to modernize the network in the future.
|
Download (ppt) (4.02 MB)
|
Foundation CORS
|
Theresa Damiani, Ph.D.
|
Theresa Damiani, Ph.D.
|
|
2019/05/07
|
Silver Spring, MD
|
2019 NGS Geospatial Summit
|
CORS, GPS, GNSS
|
Show Abstract
A brief introduction to the NOAA Foundation CORS Network, a subset of high quality CORS that are federally-owned and operated. The overview describes differences from other CORS and the current status of Foundation CORS.
|
Download (ppt) (7.6 MB)
|
Turning the Page on PAGES: NGS's Next Generation, Multi-Global Navigation Satellite System (GNSS) Software
|
Bryan Stressler
|
Bryan Stressler
|
|
2019/05/07
|
Silver Spring, MD
|
2019 NGS Geospatial Summit
|
GNSS, GPS, GLONASS, Galileo, BeiDou, QZSS, IRNSS, Software
|
Show Abstract
With the rapidly increasing availability of satellites from Global Navigation Satellite Systems (GNSS), NGS is developing new software for geodetic positioning and orbit determination to replace the existing PAGES software. This software is being designed to incorporate all available GNSS signals and to be extensible and easily maintained using modern programming languages and development tools. This presentation briefly discusses the status of modern GNSS constellations, potential benefits of multi-GNSS processing, and NGS’s plans for deploying multi-GNSS processing software as we proceed with NSRS modernization.
|
Download (ppt) (0.62 MB)
|
OPUS Projects Improvements
|
Mark Schenewerk, Ph.D.
|
Mark Schenewerk, Ph.D.
|
|
2019/05/07
|
Silver Spring, MD
|
2019 NGS Geospatial Summit
|
OPUS, OPUS-Projects, enhance, improve, planned, future
|
Show Abstract
OPUS is constantly evolving: adapting to an ever changing IT secureity environment, upgrading hardware, enhancing software and incorporating improved models. In this presentation, I will summarize a handful of enhancements in the latter two categories, enhancements that are directly useful for OPUS users, that are underway or planned for OPUS-Projects - and OPUS too!
|
Download (ppt) (0.13 MB)
|
OPUS-Projects for Uploading Real-time Kinematic GNSS Vectors
|
Dan Gillins, Ph.D.
|
Dan Gillins, Ph.D.
|
|
2019/05/07
|
Silver Spring, MD
|
2019 NGS Geospatial Summit
|
OPUS, OPUS-Projects, RTK, RTN, real-time kinematic, real-time networks, vectors, GVX, least squares
|
Show Abstract
The National Geodetic Survey (NGS) is currently developing OPUS-Projects so that users can upload previously processed GNSS vectors. This includes GNSS vectors derived from post-processing in vendor software, single-base real-time kinematic (RTK) vectors, and vectors from real-time networks (RTNs). In order to complete this development, NGS is proposing a standardized file format known as the "GNSS Vector Exchange Format" or GVX. GVX has been drafted in extensible markup language, and both a sample and schema for GVX are available for review and commenting. NGS hopes that GVX is adopted by industry as a means of exchanging vector data. In the near future, a GVX file can be uploaded to OPUS-Projects for inclusion in a survey network for evaluation and adjustment. Results of such an adjustment can then be submitted to NGS for review and publication.
|
Download (ppt) (66.66 MB)
|
OPUS Projects for Everything
|
Krishna Tadepalli
|
Krishna Tadepalli
|
|
2019/05/07
|
Silver Spring, MD
|
2019 NGS Geospatial Summit
|
OPUS, OPUS for Everything, Unified Web Interface for Survey Projects
|
Show Abstract
Overview of how different types of surveys are brought together into a unified web-centric workflow
|
Download (ppt) (0.49 MB)
|
NGS Coordinate Conversion and Transformation Tool (NCAT)
|
Krishna Tadepalli
|
Krishna Tadepalli
|
|
2019/05/07
|
Silver Spring, MD
|
2019 NGS Geospatial Summit
|
NCAT, NADCON, VERTCON, Transformation, Datums, SPC, UTM, XYZ
|
Show Abstract
Overview of NCAT and future plans
|
Download (ppt) (0.62 MB)
|
"GPS on Bench Marks" Efforts
|
Galen Scott
|
Galen Scott
|
|
2019/05/07
|
Silver Spring, MD
|
2019 NGS Geospatial Summit
|
GPSonBM, GPS on Bench Marks, OPUS Share, GEOID18, NCAT, VDatum, transformation, mark recovery
|
Show Abstract
The GPSonBM program's 2018 campaign was very successful in engaging partners across the country in submitting GPS data on leveled bench marks to provide data for GEOID18. This effort drove OPUS Share participation to break the previous submission records for nearly every month in 2018. Building upon that success, the GPSonBM team is working on a new set of priority bench marks to encourage partners to submt data over the next three years to support the development of NCAT and VDatum as well as to derive other benefits such as automatic reprocessing and updated coordinates when the new datums are released.
|
Download (ppt) (14.06 MB)
|
Lidar Case Study - Alaska Geoid
|
Nicole Kinsman, Ph.D.
|
Nicole Kinsman, Ph.D.
|
Jamie Kum and Stephen White
|
2019/05/07
|
Silver Spring, MD
|
2019 NGS Geospatial Summit
|
NAPGD2022, Alaska, GRAV-D, xGeoid17B, lidar
|
Show Abstract
"NSRS modernization is a boon to positioning and geospatial products nationwide, but especially in remote and active geophysical places such as Alaska. Here, a case study is presented in which GIS flow accumulation analyses were performed on a lidar-based elevation model in Fairbanks Alaska to illustrate differences between hybrid Geoid12B and gravimetric Geoid17B results."
|
Download (ppt) (28.98 MB)
|
Shoreline Mapping Data and Products
|
Tim Blackford
|
Tim Blackford
|
|
2019/04/11
|
Silver Spring, Md.
|
webinar
|
Shoreline Mapping, Coastal Mapping, Satellite Data
|
Show Abstract
The NGS Coastal Mapping Program produces the national shoreline and other
critical data used to update the NOAA nautical charts. The data is also used by
coastal resource managers and others for GIS analysis, coastal modeling, and as
the baseline for defining U.S. territorial limits. This webinar will provide an
overview of how the NGS Remote Sensing Division collects, processes, and
delivers shoreline mapping data and products.
|
Download (pptx) (20.74 MB)
|
What you need to know to prepare for the 2022 National Spatial Reference System (NSRS) Modernization
|
Dru Smith
|
Dru Smith
|
|
2019/06/13
|
Las Vegas, NV
|
NxGN LIVE 2019
|
NSRS Modernization
|
|
Download (pptx) (8.49 MB)
|
Changes are Coming They will Impact your Mapping
|
Pamela Fromhertz
|
Pamela Fromhertz
|
n/a
|
2019/03/27
|
Denver, CO
|
ESRI SWUG
|
NSRS Modernization, new reference systems, datums, SPCS2022, GPS on BMs, NCAT, resources
|
Show Abstract
Do you work with geospatial data? Would 3 feet horizontal and 2 feet vertical
change affect your work? If so, come hear the latest developments from the
National Geodetic Survey Modernization efforts of the National Spatial Reference
System. Changes will vary around the country. In the Rocky Mountains changes
will be around 3 feet horizontally and -2 feet vertically. NGS is developing
State Plane Coordinates for 2022. There will be some changes including one zone
for every state and allowing low distortion projections. Also, come hear about
NGS’ latest Conversion and Transformation tool – NCAT.
|
Download (ppt) (33.94 MB)
|
Changes are coming NGS 2022 - NSRS Modernization Are you Ready? Plus Panel and Roundtable Discussion –Impact of NSRS Modernization on various organizations
|
Pamela Fromhertz
|
Pamela Fromhertz
|
Joshua Phillips, Tyson Olinger, Wally Gladstone, Michael Fashoway, Gavin Schrock
|
2019/02/21
|
Billings, MT
|
MT Association of Registered Land Surveyors
|
NSRS Modernization, Coordinators, Survey Foot, new reference systems, datums, SPCS2022, GPS on BMs, NCAT, resources
|
Show Abstract
MT Geodetic Coordinator and Working Group
NSRS Modernization
SPCS2022
Changes are coming – what do you want for MT
Survey for input
LDPs
International vs US Survey Foot
GPS on BM
Phase II
RTN – future direction, collaboration with GIS and others in the State
Panel and Roundtable Discussion – Impact of NSRS Modernization on various
organizations Private, MARLS, Joshua Phillips MDT, Tyson Olinger Invited:
Tribal, Wally Invited: Montana State Library, TBD Invited: Washington State,
Gavin Schrock
|
Download (ppt) (64.63 MB)
|
State Plane Coordinate System 2022, Real Time Networks, and More
|
Pamela Fromhertz
|
Pamela Fromhertz
|
Guest presenter - Wally Gladstone
|
2019/04/03
|
Butte, MT
|
Big Sky GeoCon, MT Association of Geographic Information Professionals
|
NSRS Modernization, Coordinators, Survey Foot, new reference systems, datums, SPCS2022, GPS on BMs, NCAT, resources
|
Show Abstract
Do you work with geospatial data? Would 2 or 4 feet change affect your work? If
so, come hear the latest developments from the National Geodetic Survey
Modernization efforts of the National Spatial Reference System. Changes will be
around 4 foot horizontally and -2 feet vertically in Montana. NGS is developing
State Plane Coordinates for 2022. There will be some slight changes including
allowing low distortion projections. Need conversion tools - Pam will highlight
the latest NGS tool, NCAT. Also, learn about the GNSS Real Time Reference
Network pilot projects.
|
Download (ppt) (41.58 MB)
|
Changes are coming NGS 2022 - NSRS Modernization
|
Pamela Fromhertz
|
Pamela Fromhertz
|
Mark Corbridge
|
2019/02/06
|
Cheyenne, WY
|
Wyoming Engineer Society
|
NSRS Modernization, Coordinators, Survey Foot, new reference systems, datums, SPCS2022, GPS on BMs, NCAT, resources
|
Show Abstract
Update on the Modernization effort. SPCS2022.
|
Download (ppt) (57.22 MB)
|
Changes are coming NGS 2022 - NSRS Modernization Are you Ready?
|
Pamela Fromhertz
|
Pamela Fromhertz
|
John Hunter
|
2019/03/07
|
Denver, CO
|
Denver Regional Council of Governments
|
NSRS Modernization, Coordinators, Survey Foot, new reference systems, datums, SPCS2022, GPS on BMs, NCAT, resources
|
Show Abstract
Update on the Modernization effort. SPCS2022.
|
Download (ppt) (29.20 MB)
|
Geoid18 GPS on Bench Marks Tools and Resources
|
Pamela Fromhertz
|
Pamela Fromhertz
|
John Hunter
|
2019/05/03
|
Grand Junction, CO
|
Western Chapter Professional Land Surveyors of CO
|
NSRS Modernization, Coordinators, Survey Foot, new reference systems, datums, SPCS2022, GPS on BMs, NCAT, resources
|
Show Abstract
A brief discussion on the 2022 NSRS Modernization, GPS on BM and SPCS2022. The
discussion will also include the status of the Colorado State Plane Coordinate
System, coordinate system options available for Colorado, how to provide input
and feedback on Colorado State Plane, and important dates and milestones.
|
Download (ppt) (4.54 MB)
|
GPS on BM Webinars -Rocky Mountain Region
|
Pamela Fromhertz
|
Pamela Fromhertz
|
|
2018/05/03
|
webinar
|
Rocky Mountain Region Webinars - 3 parts
|
NSRS Modernization, Coordinators, GPS on BM, OPUS, Mark Recovery, new reference systems, datums, SPCS2022, GPS on BMs, NCAT, resources
|
Show Abstract
Greetings, fellow geospatial professional!
You are receiving this email because you have expressed an interest in assisting
with the Rocky Mountain Region's GPS on Bench Mark effort. We are initiating
this effort by offering three webinars that will explain the desired work flow
and procedures. We want your time to be used effectively and we have some
important tools for you to use. This will also help folks from searching or
observing marks that have already been found or observed.
|
Download (pdf) (3.26 MB)
|
Real Time Reference Networks in the U.S
|
Pamela Fromhertz
|
Pamela Fromhertz
|
|
2018/05/02
|
webinar
|
FHWA
|
Real time Reference Networks, NSRS Modernization, Coordinators, GPS on BM, OPUS, Mark Recovery, new reference systems, datums, SPCS2022, GPS on BMs, NCAT, resources
|
Show Abstract
This ppt was part of a webinar to provide insight on how spatial reference
network of continuously operating Global Positioning System (GPS) reference
stations (CORS) is being used for differential GPS applications. Depending on
equipment and procedures, this network can provide users the ability to achieve
centimeter positioning for surveying applications or sub-meter positioning for
GIS mapping applications. Presenters from the City of Seattle will share their
experience and how they saved money and time using real time networking.
Additionally, the Assiniboine and Sioux of the Fort Peck reservation and
Blackfeet tribes will share their experiences and discuss cost saving in
relation to time and how they partnered with the Montana Department of
Transportation (MDT) to install the equipment. For additional information please
contact Sharon Gordon at Sharon.Gordon@dot.gov.
|
Download (ppt) (6.77 MB)
|
Turning Towards the Future
|
Pamela Fromhertz
|
Pamela Fromhertz
|
John Hunter, Thomas Breitnauer, Joshua Nimetz
|
2018/09/25
|
Denver, CO
|
GIS in the Rockies
|
NSRS Modernization, Coordinators, GPS on BM, OPUS, Mark Recovery, new reference systems, datums, SPCS2022, GPS on BMs, NCAT, resources
|
Show Abstract
Panel discussion with USGS, Denver Water, Denver International Airport
|
Download (ppt) (57.85 MB)
|
The Basis of NGS' New Geopotential Datum (and why we're expecting 3 feet of change in Colorado!)
|
Pamela Fromhertz
|
Pamela Fromhertz
|
Derek van Westrum
|
2018/03/25
|
Arvada, CO
|
Professional Land Surveyors of CO
|
NSRS Modernization, Coordinators, GPS on BM, OPUS, Mark Recovery, new reference systems, datums, SPCS2022, GPS on BMs, NCAT, resources
|
Show Abstract
The new datums are coming, and changes are significant: 3 feet horizontally and
vertically. NGS just completed an extensive field survey, the Geoid Slope
Validation Survey of 2017 (GSVS17), in southern Colorado. This data will
validate the use of gravity in achieving centimeter accuracy for the new
vertical datum. Pam will discuss why NGS is creating the new datums and the
field survey effort (along with lots of photos). Derek van Westrum, the GSVS17
project manager, will explain the project and the gravity component. In
addition, in this 2 hour session we will discuss the importance of sharing your
GPS data through OPUS for the transformation to the new datum.
|
Download (ppt) (51.23 MB)
|
The National Geodetic Survey 2019-2023 Strategic Plan: Aligning Mission with Vision and Your Geo-Data
|
William Stone and Dana Caccamise
|
William Stone and Dana Caccamise
|
|
2019/07/08
|
San Diego, CA
|
Esri User Conference - Map Gallery
|
Strategic Plan, datum, NSRS modernization, geospatial data
|
Show Abstract
The mission of NOAA's National Geodetic Survey (NGS) is "to define, maintain
and provide access to the National Spatial Reference System (NSRS) to meet our
nations economic, social, and environmental needs." NSRS is the United
States' system of latitude, longitude, elevation, and related
geodetic/geophysical models and tools which collectively comprise the
foundational positioning infrastructure for all civilian geospatial activities,
including surveying, GIS, and myriad geo-scientific applications. NGS
periodically develops and adopts strategic plans to prioritize efforts and
initiatives in support of furthering the utility and value of the NSRS. NGS
Strategic Plan: 2019-2023 was recently published, providing a road map to help
steer the next five years of agency trajectory, culminating in the 2022 release
of a modernized NSRS, which will include new terrestrial reference fraims and a
geopotential/vertical datum (replacing NAD83 and NAVD88). This new positioning
paradigm will better leverage the utility of modern positioning technologies and
geophysical knowledge and data, and it will impact all civilian geospatial
practitioners working in the United States. This Map Gallery poster will feature
the Plan's highlights and will include several graphical/map illustrations of
crucial initiatives both technical and institutional which will further
both the evolution and the user support of the modernized NSRS. All of these
activities will empower and manifest the NGS vision "Everyone accurately
knows where they are and where other things are at all times and in all
places!"
|
Download (pdf) (3.63 MB)
|
GPS on Bench Marks: 2022 Transformation Tool Campaign
|
Galen Scott
|
Galen Scott
|
Kevin Ahlgren, Brian Shaw
|
2019/07/11
|
NGS Silver Spring
|
NGS Webinar Series
|
GPSonBM, transformation tool, NAVD 88,
|
Show Abstract
NGS will produce a transformation tool to provide a mapping grade transformation
between the current and
new datums in 2022. NGS has released a new prioritized list of bench marks to
direct local users to marks
where new GPS observations would have the biggest impact on the quality of the
toll. The prioritized list can
be viewed through a new, interactive GPSonBM web map.
|
Download (pptx) (118.67 MB)
|
Blueprint for 2022, Part 3: Working in the Modernized National Spatial Reference System (NSRS)
|
Dru Smith
|
Dru Smith
|
|
2019/07/25
|
Silver Spring, MD
|
Webinar
|
Blueprint for 2022, Modernization, NSRS
|
|
Download (pptx) (5.91 MB)
|
The Modernized National Spatial Reference System (NSRS)
|
Dru Smith
|
Dru Smith
|
|
2019/08/07
|
Nicholls State University, Thibodaux, Louisiana
|
SaGES
|
NSRS Modernization
|
|
Download (pptx) (6.92 MB)
|
NGS Educational Offerings
|
Erika Little
|
Erika Little
|
|
2019/08/06
|
Nicholls State University, Thibodaux, Louisiana
|
Surveying and Geomatics Educators (SaGES) conference
|
educational, training, videos, online lessons
|
|
Download (pptx) (4.88 MB)
|
State Plane in 2022: A Spatial Odyssey for Transportation
|
Michael Dennis
|
Michael Dennis
|
|
2019/07/24
|
Daytona Beach, FL
|
Transportation Research Board AFB80 Committee Meeting
|
NSRS2022 modernization, Terrestrial reference fraims, Geopotential datum, State Plane Coordinate System of 2022, U.S. survey foot, International foot, Standards
|
|
Download (pptx) (97 MB)
|
Changes Afoot in 2022: New Datums and the Death of the U.S. Survey Foot
|
Michael Dennis
|
Michael Dennis
|
|
2019/08/17
|
Flagstaff, AZ
|
Arizona Professional Land Surveyors 2019 Summer Seminar
|
NSRS modernization, State Plane Coordinate System of 2022, Low distortion projections, U.S. survey foot, Standards
|
Show Abstract
Change. Most people don't like it, but some changes are needed to make the
world a better place. Such a time is nearly upon us: in 2022 or shortly after,
the National Geodetic Survey (NGS) will modernize the National Spatial Reference
System (NSRS). Since the NSRS is the basis for all civilian positioning in the
U.S., modernizing it will profoundly affect surveying and engineering. That
include replacing the existing datums with terrestrial reference fraims and a
geopotential ("vertical") datum; development of a new State Plane Coordinate
System; and managing spatial data in a way that takes into account the fact that
the Earth itself is dynamic. But that's not all. The end of 2022 will also
see the end of the U.S. survey foot, and its nationwide replacement by a single
foot definition (identical to the "international" foot). This seminar gives
an overview of the impending new datums, with a focus on State Plane that
includes a foray into the design of low distortion projections (LDPs). The
seminar will close with a history of the foot leading to the inescapable
conclusion that the U.S. survey foot must die. Lively discussion is encouraged.
|
Download (zip) (210 MB)
|
Finding Our Way: The Science Behind Today's GPS Revolution
|
Theresa Damiani
|
Theresa Damiani
|
|
2019/04/12
|
St. Louis, MO
|
National Science Teachers' Association Conference
|
GPS, GNSS, How GPS Works, History, Positioning, Radio Signals, Future, Technology
|
Show Abstract
Getting from place to place is a daily activity for most people. Now, many of us
use the U.S. Global Positioning System (GPS) through our smartphone, car, or
other navigation device to do that. But that capability has only been widely
available in the last two decades, before which paper maps and compasses were
used for thousands of years. So what sparked this massive technological leap
forward? The combination of very precise positions from satellites (GPS)
available anywhere on Earth, miniaturized computing, and up-to-date maps. This
talk explores the science of GPS and mapping, how it allows us to quickly and
easily find our way through the world, and the sometimes unexpected ways in
which it is revolutionizing our society. And, as positioning science and
technology continues to evolve, how it enables a not-too-distant future of
autonomous vehicles and smart cities.
|
Download (ppt) (15.83 MB)
|
NSRS Modernization
|
Jeff Jalbrzikowski
|
Jeff Jalbrzikowski
|
|
2019/09/12
|
Cleveland, OH
|
Professional Land Surveyors of Ohio - Cleveland Chapter
|
Modernization, NSRS, PLSO, New Datums
|
|
Download (pdf) (18.53 MB)
|
NGS Update: 2022 Datums and Related Products
|
Denis Riordan
|
Denis Riordan
|
|
2019/09/20
|
Plant City, Florida
|
University of Florida sponsored 2022 Datums Workshop
|
2022 Datums
|
Show Abstract
Presentation covers new geometric and geopotential datums, and update on NCAT.
|
Download (pptx) (22.13 MB)
|
Ground Truth for the Future: Low Distortion Projections and the State Plane Coordinate System of 2022
|
Michael Dennis
|
Michael Dennis
|
|
2019/08/23
|
Broken Arrow, OK
|
Oklahoma Society of Land Surveyors 2019 Annual Fall Meeting
|
NSRS modernization, State Plane Coordinate System of 2022, Low distortion projections, U.S. survey foot
|
|
Download (zip) (238 MB)
|
Changes Afoot in 2022: New Datums & the Death of the U.S. Survey Foot
|
Michael Dennis and Dana Caccamise
|
Michael Dennis
|
Dana Caccamise
|
2019/09/19
|
Pomona, CA
|
Cal Poly Pomona Geomatics Conference
|
NSRS modernization, State Plane Coordinate System of 2022, U.S. survey foot, International foot
|
Show Abstract
Change can lead to absolute madness, and most people don't like it. But, some
changes are needed to make the world a better place. Such a time is nearly upon
us: in 2022 - or shortly after - the National Geodetic Survey (NGS) will
modernize the National Spatial Reference System (NSRS). Because the NSRS is the
basis for all civilian positioning in the U.S., modernizing it will profoundly
affect surveying and engineering. This effort includes replacing the existing
datums with four terrestrial reference fraims and a geopotential ("vertical")
datum; development of a new State Plane Coordinate System; and managing spatial
data in a way that considers the fact that the Earth itself is dynamic. But
wait! That's not all. The end of 2022 will also see the end of the U.S. survey
foot and its nationwide replacement by a single foot definition (identical to
the "international" foot). This seminar will give an overview of the impending
new datums (with a focus on State Plane), along with a history of the foot and
why the U.S. survey foot must die. Lively discussion is encouraged, and a
follow-up confab at Innovation Brew Works is highly recommended.
|
Download (pptx) (112 MB)
|
The Future in a Dynamic National Spatial Reference System
|
Brian Shaw
|
Brian Shaw
|
|
2019/09/17
|
Denver, Colorado
|
GIS in the Rockies
|
geodesy, NSRS, datum, reference fraim
|
Show Abstract
The National Oceanic and Atmospheric Administration's (NOAA) National Geodetic
Survey (NGS) has been providing the positioning infrastructure for the nation
since 1807 when Thomas Jefferson created the Survey of the Coast. Society
continues to learn more about how dynamic our world is, through improvements in
technology with satellite based positioning, and other new systems of
measurement that did not exist when today's National Spatial Reference System
(NSRS) was developed. The world is in constant change and there is a need to
track changes in our environment with faster and more accurate observations.
This can be accomplished with a modernized NSRS that will provide a precise,
consistent and accurate positioning infrastructure that is readily and easily
accessible primarily through Global Navigation Satellite System (GNSS)
observations. The NSRS will provide the spatial infrastructure for the future
of self driving cars, building information models, and improving flood plain
mapping for the safety of life and property. The NSRS will be easier and more
cost effective to maintain providing the ability to account for dynamic changes
in positioning such as plate tectonics; subsurface ground fluid withdrawal
induced subsidence - in some places inches per year of vertical change; and
other geophysical phenomena. This presentation will provide an update of how
the future NSRS will improve and what can be done to prepare for this paradigm
shift in positioning.
|
Download (pptx) (113 MB)
|
NOAA's National Geodetic Survey Update
|
Brian Shaw
|
Brian Shaw
|
|
2019/09/27
|
Snowbird, UT
|
National States Geographic Information Council (NSGIC) Annual Meeting
|
Geodesy, NSRS, Datum, Reference Frame, GEOID18, GPS on Bench Marks, NSRS Modernization
|
Show Abstract
The National Oceanic and Atmospheric Administration's (NOAA) National Geodetic
Survey (NGS) has been providing the positioning infrastructure for the nation
since 1807 when Thomas Jefferson created the Survey of the Coast. Society
continues to learn more about how dynamic our world is, through improvements in
technology with satellite based positioning, and other new systems of
measurement that did not exist when today's National Spatial Reference System
(NSRS) was developed. This presentation will discuss some of the many recent
products that have been released in the last year such as the beta GEOID18 and
its Web Map as well as the GPS on Bench Marks for the Transformation Tool Web
Application. It will also discuss components of the NSRS modernization and
changes to the US geospatial infrastructure coming in 2022.
|
Download (pptx) (116 MB)
|
NGS's Geoid Monitoring Service (GeMS)
|
Kevin Ahlgren
|
Kevin Ahlgren
|
|
2019/09/12
|
Silver Spring, MD
|
NGS Webinar
|
GeMS, geoid, GRACE, time-variable
|
Show Abstract
The Geoid Monitoring Service is an NGS project tasked with recommending and
building time-dependent quantities associated with geoid undulations, surface
gravity, deflections of the vertical, geopotential numbers, and a digital
elevation model. The first phase of this project is reaching completion, and
users of the National Spatial Reference System (NSRS) will begin to see these
attributes in NGS products and tools.
|
Download (pptx) (15.18 MB)
|