Impact of the 1997 Indonesian Fires on Tropospheric Ozone and its Precursors

Abstract

A global chemical transport model, called MOZART, is used to investigate the impact of the 1997 Indonesian biomass fires on the distribution of tropospheric ozone and its precursors. Due to the high release of methane, carbon monoxide, non-methane hydrocarbons, and NO, by the forest fires and, more importantly, the peat fires, ozone increases significantly over the source regions (Sumatra and Kalimantan), and the tropospheric O-3 column increases by 25-30 DU over Indonesia in November. Our results indicate that the model reproduces with some accuracy the impact of the biomass fires on ozone when the magnitude of the emissions are properly accounted for in the simulations. Because of rapid venting of pollutants out of the boundary layer in the tropics, and their subsequent redistribution by large-scale transport processes, the simulations indicate a significant impact of this local event on the composition of the free troposphere on a regional scale.