TRACE-A was deployed in August 1992 to determine the cause and source of high concentrations of ozone that accumulate over the Atlantic ocean between southern Africa and South America during the months of August through October. The enhanced levels of ozone were observed to be the highest during the southern hemisphere's springtime, a period of intense burning of vegetation in both southern Africa and South America. The TRACE-A results showed the link between the biomass burning and the ozone pollution. TRACE-P, conducted in March/April 2001, had as it's major objectives to 1) determine the chemical composition of the Asian outflow over the western Pacific in spring in order to understand and quantify the export of chemically and radiatively important gases and aerosols, and their precursors, from the Asian continent and to 2) determine the chemical evolution of the Asian outflow over the western Pacific in spring and to understand the ensemble of processes that control the evolution.