Interannual variability of the Southern Hemisphere circulation: representativeness of the year of the Global Weather Experiment.

Abstract

An anlysis has been made of the intraseasonal and interannual variability of mean circulation and eddy statistics for both summer and winter in the Southern Hemisphere. Total variance fields of geopotential height, the north-south and east-west wind components and poleward transient eddy momentum fluxes at 500 mb are analyzed along with their contributions from two broad frequency bands covering 2-8 days and 8-64 day period fluctuations. Largest interannual variability occurs between 40-60oS in association with the main jet stream in summer or the polar jet stream in winter and the main belt of eddy activity within each season. -from Author