Circulation Features Over the South Pacific During 10–18 January 1979

Abstract

A diagnostic study of the time-averaged large-scale circulation features over the equatorial and South Pacific Ocean during 10?18 January 1979, FGGE SOP-1, is presented. Results are based on ECMWF Level III-b analyses for an area bounded by 10°N, 105°W, 42.5°S and 170°E. During the nine day period, the South Pacific Convergence Zone (SPCZ) and its accompanying cloud band were quasi-stationary features in the area of study. Analyses of surface pressure, geopotential height, horizontal winds, temperature, relative humidity, vertical p-velocity (?), horizontal divergence and relative vorticity are presented and discussed. Particular attention is devoted to examining the structure of the SPCZ through the use of vertical cross sections along and across both the west-east (zonal) and northwest-southeast (diagonal) portions of the zone.