Improving the seasonal cycle and interannual variations of biomass burning aerosol sources

[摘要] This paper suggests a method for improving current inventories of aerosol emissions frombiomass burning.The method is based on the hypothesis that, although the total estimateswithin large regions are correct, the exact spatial and temporal description can beimproved. It makes use of open fire detection from the ATSR instrument that is available since 1996.The emissions inventories are re-distributed in space and time according to the occurrence of open fires.Although the method is based on the night-timehot-spot product of the ATSR, other satellite biomass burning proxies (AVHRR,TRMM, GLOBSCAR and GBA2000) show similar distributions.

The impact of the method on the emission inventories is assessed using an aerosol transportmodel, the results of which are compared to sunphotometer and satellite data.The seasonal cycle of aerosol load in the atmosphere is significantly improved in severalregions, in particular South America and Australia.Besides, the use of ATSR fire detectionmay be used to account for interannual events, as is demonstrated on the large Indonesianfires of 1997, a consequence of the 1997-1998 El Niño. Despite these improvements, thereare still some large discrepancies between the simulated and observed aerosol optical thicknesses resulting from biomass burning emissions.

[学科分类] 大气科学