Transport of biomass burning smoke to the upper troposphere by deep convection in the equatorial region

During LBA-CLAIRE-98, we found atmospheric layers with aged biomass smoke a t altitudes >10 km over Suriname. CO, CO2, acetonitrile, methyl chloride, h ydrocarbons, NO, O-3, and aerosols were strongly enhanced in these layers. We estimate that 80-95% of accumulation mode aerosols had been removed duri ng convective transport. Trajectories show that the plumes originated from large fires near the Brazil/Venezuela border during March 1998. This smoke was entrained into deep convection over the northern Amazon, transported ou t over the Pacific, and then returned to South America by the circulation a round a large upper-level anticyclone. Our observations provide evidence fo r the importance of deep convection in the equatorial region as a mechanism to transport large amounts of pyrogenic pollutants into the upper troposph ere. The entrainment of biomass smoke into tropical convective clouds may h ave significant effects on cloud microphysics and climate dynamics.