Depth-Longitude Gridding

All of the fields displayed as depth-longitude sections are fields of gridded monthly or 5-day means. Gridding was done by 1) removing the Kessler (1994) CTD/XBT Objective Analysis from the temperatures after bilinearly interpolating it to a 1° by 1° latitude-longitude grid, and in the case of 5-day means, also interpolating the climatology to the data times. 2) linearly interpolating the monthly or 5-day data anomalies at the nominal TAO/TRITON array coordinates to these standard depths:

0, 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, 120, 130, 140, 160, 180, 200, 225, 250, 275, 300, 400, 500 (m)

3) linearly interpolating in longitude to 1° spacing, 4) 21° triangle filtering in longitude, 5) distance-weighted binomial (1/4-1/2-1/4) filtering in depth, and 6) adding these gridded and smoothed anomalies to the Kessler objective analysis to produce the mean depth-longitude fields.

The locations of data input to the gridding routine are indicated by the little x's on the plots.

For more information on the Kessler (1994) Objective Analysis of Historical CTD and XBT temperatures, see the Climatology Background page, and to see plots of the Kessler Analysis, see the Climatology page under the "Depth-Longitude Sections of Temperature".