Impacts of different biomass burning emission inventories: Simulations of atmospheric CO concentrations based on GEOS-Chem.

Biomass burning has substantial spatiotemporal variabilities. It contributes significantly to the dynamics of global CO distributions and variances. Quantifying the impacts of biomass burning emissions on atmospheric CO concentrations is essential for global and regional carbon cycles and budgets. In this study, we performed several numerical experiments by switching and replacing inventories to estimate the impacts of four biomass burning emission inventories on atmospheric CO concentration simulations in 2006-2010 based on the global chemical transport model, GEOS-Chem. The results highlighted similarities and differences in the annual and seasonal variability of biomass burning emissions and simulated CO concentrations at global and regional scales. Based on four different biomass burning emission inventories, we found that biomass burning emissions could lead to a global CO concentration increase of 2.4 ppm annually. Africa contributed the largest global CO emissions among all continental regions, where the maximum CO concentration increase could reach 7.9-13.0 ppm in summer. Model evaluation results showed that simulation using the Quick Fire Emissions Database (QFED) as the model priori biomass burning emission inventory had the best performance compared with the satellite and surface observations. The sensitivity of simulated CO concentrations to the uncertainties in different biomass burning emission inventories was high in southern South America and most areas of the Eurasian continent, and low in central Africa and Southeast Asia. This study furthers our understanding of the critical role of biomass burning in atmospheric CO and indicates an urgent need to improve the accuracy of biomass burning emission estimates in CO simulations.