TOTAL OZONE AND SYNOPTIC WEATHER RELATIONSHIPS OVER SOUTHERN AFRICA AND SURROUNDING OCEANS

Relationships between Total Ozone Mapping Spectrometer (TOMS) total oz one and synoptic weather systems for a region bounded by longitudes 10 degrees W-50 degrees E and latitudes 0 degrees-50 degrees S are prese nted. Least squares regression analysis revealed a generally poor but negative relationship between total ozone and the heights of the 500, 300, and 100 hPa geopotential surfaces at nine selected stations for t he period 1987 to 1988. The relationship strengthens with increasing l atitude and suggests a physical link with the midlatitude cyclone whic h facilitates the injection of stratospheric ozone rich air into the t roposphere. In the tropics the link with middle to upper tropospheric meteorological parameters is weak. Analysis of daily relationships bet ween gridded TOMS ozone and gridded European Centre for Medium-Range W eather Forecasts (ECMWF) geopotential height data over the study area showed considerable variations, indicative of varying synoptic weather situations. Case studies of a cutoff low sequence and a subtropical a nticyclone system were selected as examples of synoptic situations whi ch accounted for the highest and lowest correlations, respectively. Th e contrasting dynamics operating in these systems are highlighted.