Comparison of Synoptic and Climatologically Mapped Sections in the South Pacific Ocean

Abstract

To understand the extent to which oceanic climate shifts could be detected, a South Pacific climatology has been used to create pseudosections of temperature, salinity, and other tracers along a zonal and meridional lines at 15°S and 90°W, respectively. Interpolations from the climatology were made using combined empirical orthogonal functions and objective mapping. Comparisons are made with independent measurements, taken in 1987, of temperature and salinity at 15°S. Temperature and salinity fields between the surface and 300 db along the 15°S section are predicted with an uncertainty sufficiently small to display significant differenccs in temperature and salinity related to El Niño of 1987. The 90°W pseudosection is a forecast of a synoptic section to be obtained as part of WOCE in 1992. Explicit values for the smallest temperature shift with depth that could be detected are produced.