Preliminary results of dry-season trace gas and aerosol measurements over the Kalahari region during SAFARI 2000

Trace gas and aerosol data were collected through a series of flights over the arid Kalahari Makgadikgadi Pan system. These data show statistically significant spatial and temporal variations in ozone concentrations, while SO₂ concentrations were found to be relatively constant. Transport and photochemical production processes are two possible mechanisms for the observed temporal variation in ozone concentration. The presence of certain types of vegetation that emit ozone-precursor gases may account for some of this spatial variation. Aerosols may also be formed as a result of the gases emitted. These species of vegetation alter atmospheric chemistry characteristics and influence the climate. In arid regions, the presence of trace gases and aerosols has an important effect on radiation budget and cloud formation processes, which are significant controlling factors of climate. This paper is a first attempt to synthesize the relationship between surface ecology and atmospheric chemistry of arid environments to better understand the regional climate.