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.