What
climatologies are used in TAO data display?
The various Climatologies used by the TAO /
TRITON Project to compute anomalies are briefly
described below.
Reynolds and Smith AOI SST Climatology
(1971 - 2000)
The AOI SST climatology is an optimum interpolation
analysis of Sea Surface Temperature with an adjusted
base period of 1971 to 2000, on a global 1 degree by 1
degree by 1 month grid. For further information, please
see Reynolds, R. W. and T. M. Smith, 1995: "A
high-resolution global sea surface temperature
climatology". J. Climate, V8, N6 (JUN), p
1571-1583.
Kessler Objective Analysis of XBT and CTD
Temperatures
The Kessler temperature climatology is a 4-D objective
analysis of historical XBT and CTD temperatures, which
uses best estimates of the correlation lengths in
Longitude, Latitude, and Time to grid the data. Dr.
Kessler is an Oceanographer here at PMEL/NOAA in
Seattle.
The CTD data used in the analysis consist of
all the available data from the earliest years these
observations were taken through 1991. The XBT data
range in time from 1970 to 1987.
For further information about the methods used
to create the Kessler climatology, please refer to
Kessler, W.S., 1990: "Observations of long Rossby waves
in the northern tropical Pacific". J. Geophysical
Research, 95(C4), 5183-5217, and Kessler, W.S. and J.P.
McCreary, 1993: "The annual wind-driven Rossby wave in
the subthermocline equatorial Pacific". J. Physical
Oceanography, 23(6), 1192-1207.
This climatology is used for gridding the TAO
/ TRITON subsurface temperatures in Longitude-Depth and
Latitude-Depth sections. For more information on how
these TAO / TRITON data are gridded, see the zonal-depth gridding and meridional-depth gridding web
pages.
COADS Winds (1946 - 1989)
The COADS climatologies of Zonal and Meridional Wind,
Scalar Wind Speed, and Wind direction, are used for
computing TAO / TRITON Wind anomalies, and for gridding
Zonal and Meridional Winds and Scalar Wind Speed. For
example plots of TAO / TRITON Winds and their anomalies
see the TAO / TRITON Data Display web page. For
information on the gridding methods mentioned above,
see the TAO / TRITON gridding web
pages.
COADS Relative Humidity (1946 -
1989)
The Relative Humidity (RH) climatology was derived
from the COADS Specific Humidity (SH) climatology. The
SH climatology was converted to RH using a routine
written by Ms. Margie McCarty at NOAA/PMEL, which takes
as input SH, pressure, and Air
Temperature.
This climatology is used for computing TAO /
TRITON RH anomalies, and for gridding RH in the Lat-Lon
Maps and Latitude-Time and Time-Longtitude section
plots. For example plots of RH see the Section Plots on
the TAO / TRITON Data Display web page. For
information on these gridding methods, see the TAO /
TRITON gridding web pages.
20°C Isotherm depth
The 20 Degree C Isotherm Depth climatology was
computed from the Kessler temperature climatology (see
above), by linear interpolation of depth versus
temperature.
This climatology is used for computing TAO /
TRITON 20 degree C Isotherm depth anomalies, and for
gridding 20 C depths in the Lat-Lon Maps and
Latitude-Time section plots. For example plots of 20C
Depth see the TAO / TRITON Data
Display web page. For information on these gridding
methods, see the TAO / TRITON gridding web
pages.
Dynamic Height
The Dynamic Height climatology was computed from the
Kessler temperature climatology (see above), by
vertically integrating the specific volume anomaly
using a set of long-term mean temperature-salinity
relations, one for each grid location, derived from the
World Ocean Atlas (See Conkright et al 2002: "World
Ocean Atlas 2001: Objective Analyses, Data Statistics,
and Figures, CD Rom Documentation").
This climatology is used to compute Dynamic
Height anomalies, and for gridding Dynamic Heights in
the Lat-Lon Maps and Latitude-Time section plots. For
example plots of Dynamic Height see the TAO / TRITON Data
Display web page. For information on these gridding
methods, see the TAO / TRITON
gridding web pages.
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