The Structure of the Stratosphere in the Southern Hemisphere During Late Winter 1973 as Observed by Satellite

Abstract

The use of satellite data of constructing synoptic analyses is appropriate in the stratosphere where the most important disturbances are very large scale and slowly moving. Nimbus 5 data are applied to a study of the structure of the stratosphere in the Southern Hemisphere during the period 1 July to 6 September, 1973. The eddy amplitudes and transports are highly variable in time and are greatest during active periods which occur approximately once a month. The structure of the waves identified by zonal Fourier analysis is also variable in time and is related to the stages of growth and decay of the wave amplitude. The characteristic scales of the disturbances are determined by space-time cross-spectral analysis. In the stratosphere the circulation is dominated by wavenumbers 1 and 2 which have time scales in excess of two weeks. Wavenumber 1 is primarily stationary and oscillates in time, while wavenumber 2 travels eastward. Also apparent is a wavenumber 3 component which travels eastward with a period of about 6 days and has its maximum amplitude in the mid-stratosphere.