All of the fields displayed as meridional-depth sections are fields of gridded monthly means. Gridding was done by
1) removing the Kessler (1994) CTD/XBT Objective Analysis from the temperatures,
2) linearly interpolating to these standard depths (m):
0, 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, 120, 130, 140, 160, 180, 200, 225, 250, 275, 300, 400, 500
3) linearly interpolating in latitude, 4) 5-degree triangle filtering in latitude, and
5) distance-weighted binomial (1/4-1/2-1/4) filtering in depth.

These gridded and smoothed anomalies are then added to the Kessler objective analysis to produce the mean YZ field. This gridding method is a variant of that used for the XY maps which was developed by Dr. William S. Kessler, Dr. Michael J. McPhaden, and Dai C. McClurg, all at NOAA/PMEL.

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