Intercomparison of Biomass-Burning Emissions Datasets Using a Global Aerosol Model

Abstract

Aerosols from biomass burning (BB) emissions need to be properly constrained in global and regional models, in order to improve our understanding of their overall environmental impacts. In this study, we compared six BB aerosol emission datasets for 2008 globally as well as in 14 sub-regions. The datasets are: (1) GFED3.1 (Global Fire Emissions Database version 3.1); (2) GFED4s (Global Fire Emissions Database version 4 with small fires); (3) FINN1.5 (Fire INventory from NCAR version 1.5); (4) GFAS1.2 (Global Fire Assimilation System version 1.2); (5) FEER1.0 (Fire Energetics and Emissions Research version 1.0), and (6) QFED2.4 (Quick Fire Emissions Dataset version 2.4). Although biomass burning emissions of aerosols from these datasets showed similar spatial distributions, their global total emission amounts differed by a factor of 3-4, ranging from 13.76 to 51.93 Tg for organic carbon and from 1.65 to 5.54 Tg for black carbon. These differences translate to similar degrees of disagreement when these emissions are used in the forecasting of surface PM2.5 concentrations. We found that the differences between these six BB emission datasets are attributable to the approaches and input data used to derive BB emissions, such as whether aerosol optical depth (AOD) from satellite observations is used as a constraint, whether the approaches to parameterize the fire activities are based on burned area, active fire count or fire radiative power (FRP), and which set of emission factors was used in deriving them. In this presentation, we will report the results of the comparison of these BB aerosol emission datasets.