The southern high latitude troposphere (south of 60o S), in contrast to the Arctic troposphere, lies over an elevated ice- covered continent and is completely surrounded by the extensive and biologically active southern oceans. It links the rest of the global atmosphere and the oceans with the Antarctic ice sheet and stratosphere that are the focus of intense global change research today. Relatively few coordinated studies of Antarctic tropospheric chemistry and its controlling factors have been undertaken, despite the immense potential of tropospheric processes to affect climate, for example through changes in the production of cloud nuclei, and hence cloud metaphysics properties, that may ultimately and significantly affect the radiation balance over the high latitude oceanic regions. The topics to be highlighted in this symposium are: 1. Aerosols and gases in the troposphere: sources, sinks, and occurrence. 2. Air-surface exchange. 3. Troposphere-stratosphere exchange. 4. Ice-snow chemistry related to tropospheric composition and climate. 5. Chemistry and physics of clouds. 6. Role of meteorological processes.
