The relationship between interannual variability in the 200 mb tropical wind field and the Southern Oscillation.

Abstract

A substantial portion of the interannual variability in the 200 mb circulation is shown to be related to the Southern Oscillation. The anomalous circulation in the Pacific is characterized by a pair of anticyclonic/cyclonic anomalies straddling the equator during periods of low/high Southern Oscillation Index. Zonal wind differences of 8-11 m s-1 between low- and high-Index phases of the SO were found near 25oN, 25oS and near the equator in the central Pacific.-from Author