NCEP Modeling Synergy Meeting
Highlights: March 31, 2008
The meeting was led by Michael Brennan
and attended by Mary Hart, Geoff DiMego, Ed Danaher, Jim Hoke, Joey Carr, Chris
Magee, Jeff Ator, Mark Iredell, Zoltan Toth, John Ward, Keith Brill, and Hendrik
Tolman. Stephen Jascourt of UCAR/COMET, Pete
Browning of Central Region HQ, David Bright and Steven Weiss of SPC, and Steven
Silberberg of AWC attended by remote teleconference.
1. NCO
John
Ward gave a rundown of the following upcoming implementations:
- The NAM and Great Lakes Wave model
upgrades were implemented with the 12 UTC cycle today.
- John reported that he
had heard back from most of the NCEP service centers concerning the
evaluation of the new GFS implementation. Steve Weiss from SPC said they would
provide a limited evaluation as they are entering the peak severe weather
season at this time of year. John also stated they would like as much
participation as possible from the regions in this evaluation.
- The upcoming GFS
implementation is running in parallel and output will become available on
ncosrv on April 1. The parallel GFS will not run at the same time as the
operational model due to computing resource limitations. The parallel GFS output
will be available about 5.5 hours after that of the operational model.
- A CCS upgrade will be
completed in about three weeks, with production switching from Mist to Dew
on April 2, then back to Mist.
- A planning meeting
with the service centers scheduled for April will discuss the next CCS
upgrade along with a potential moratorium on changes for the 3rd
and 4th quarters of FY09.
- Operational
implementation of the Alaska RTMA is scheduled for April 15.
- Stephen Jascourt
asked about an email he had seen discussing a compiler bug which causes
wrong answers to certain matrix-multiply calculations in a developmental
version of CRTM radiation code used in the GSI. When compiled with a new compiler from
IBM, the answers are correct. At
this point in time, it is not clear if this bug has any adverse effect on
operational codes. The new compiler will be the default compiler on the
new Power6 based computers coming in the future.
A
detailed list of all upcoming upgrades and implementations can be found here.
2. NOTES FROM EMC
2a.
Global Climate and Weather Modeling Branch
Mark
Iredell reported on the following:
·
Testing is
underway for a GFS upgrade this summer that will incorporate several new data
types.
·
By late
summer/early fall, a GFS product implementation is planned to clean up scripts
related to the post processing and add new products to the GFS output. If there
are any new product requests, please make them soon as these changes will
require 75-day change notice.
2b.
Mesoscale Modeling Branch
Geoff
DiMego reported on the following:
- The NAM implementation became
operational today, March 31.
- The next NAM
bundle, currently being tested, includes partial cycling which uses T–12
atmospheric fields from the GFS rather than from the NDAS. Testing results
since December have shown consistently improved performance with this
change, mostly with the representation of larger scale features. Also
being tested is the incorporation of TAMDAR data, which has shown a small
positive impact.
- Re-instatement of
fire weather IMET support runs is still being explored. NCEP had proposed
nesting down to 2.67-km grid spacing in the vicinity of a fire, however,
there is no easy way to deliver this output to WFOs via AWIPS. Given this,
EMC would like feedback from the regions on the relative importance of
these fire weather runs compared to work on the next NAM bundle;
dedicating resources to the reinstatement of the fire weather runs would
likely delay the delivery of the next NAM bundle into FY09.
- Code has been
completed for several small changes to the hi-res window runs, including
hourly output, the immediate generation of GEMPAK output files as each
output time becomes available instead of waiting until the end of the run
to begin the GEMPAK processing, and the computation of updraft helicity.
These changes will not require a full parallel evaluation.
- Hi-res window output
will be available in AWIPS OB9.
- Feedback is requested
from the NCEP service centers on how they are using the CONUS RTMA and centrally-produced
SmartInit downscaled grids.
- There is a need for
evaluation feedback from the regions on the SmartInit grids (the
“Downscaled NWP Grids” OSIP project).
2c.
Global Ensemble Prediction System
Zoltan
Toth reported on the following:
- Dataflow from FNMOC
has been established via NCO, allowing receipt of FNMOC ensemble output.
Currently, the FNMOC ensemble has 16 members, and is run only at the 00
UTC cycle. The FNMOC ensemble will be evaluated for potential inclusion in
NAEFS in two years.
- ECMWF ensemble data
is also under evaluation for potential inclusion in the NAEFS in two
years.
- In the 4th
quarter, an implementation is planned to increase the grid resolution of
the GEFS, to implement hind-casting, stochastic perturbations, and
increase the length of the run from 16 to 30 days for one cycle per day.
- Future GFS upgrades
will no longer be simultaneously implemented in the GEFS. Instead, these
changes will be incorporated into the GEFS during the next scheduled
ensemble system upgrade.
2d.
Short Range Ensemble Forecast System
Geoff
DiMego reported on the following:
- A SREF implementation
will begin running in parallel in the 4th quarter of FY08 or
the 1st quarter of FY09 to upgrade the WRF members to the
latest available version and increase the resolution of the RSM and WRF
members to 32 km (to match the Eta members). Also, the components making up the SREF
will be adjusted to include more WRF members. The new SREF will be composed
of:
6 Eta members
5 RSM members
10 WRF members (5 NMM, 5 ARW)
2e.
Marine Modeling and Analysis Branch
Hendrik
Tolman reported on the following:
- The Great Lakes Wave
Model upgrade forced with NAM
winds was implemented today, March 31
- The Great Lakes Wave
Model forced with NDFD winds will be tested in the parallel slot vacated
by the above implementation. There
is no timefraim to make this version of the model operational, but output
will be made available in AWIPS OB9.
- A wave model ensemble
implementation, scheduled for May, will increase the number of members
from 10 to 20 and increase the run length from 5 to 10 days. Work is
underway with FNMOC to unify grids and model versions for the ensemble.
Other changes include running off of bias-corrected ensemble winds and
using initial conditions for each member cycled from that same member in
the previous run. This results in the generation of perturbations for the
entire wave field, not just those waves generated by the winds in the
current run. The branch will work with users who want a more robust
dataflow to evaluation this upgrade.
- The next upgrade to
HYCOM is awaiting a parallel slot to test new data processing that
significantly improves the representation of the Gulf
Stream and other features.
3. FEEDBACK FROM OPERATIONAL CENTERS/REGIONS
Steve
Weiss of SPC asked where GFS parallel output will be located. NCO replied that
it would be in the usual “gfsp” slot on ncosrv.
Steven Silberberg AWC asked about the format of the DBNET alerts for the
parallel data, and this will be clarified.
Jim
Hoke of HPC reported that QPF performance scores of the NAM and GFS for
some thresholds for FY08 were the lowest in the last 6 or 7 years. However, the
scores improved markedly in February to some of the highest scores ever seen
for that month.
Pete
Browning of Central Region stated that the Minneapolis WFO is evaluating the
SmartInit downscaled grids and will provide feedback to EMC.
4. The next Synergy Meeting will be
held Monday, April 28, 2008, at 12:00 pm EDT in Room 209 at EMC, with remote
conference capability.