A Multi-model Evaluation of Aerosols over South Asia: Common Problems and Possible Causes

Abstract:

Atmospheric pollution over South Asia attracts special attention due to its effects on regional climate and water cycle such as Asia monsoon. However, numerous studies have revealed great challenges for current global models to adequately represent aerosols in South Asia, thus this impairs models’ reliability of projecting future climate. In this study, the spatio-temporal aerosol distributions over South Asia from seven global aerosol models are systematically evaluated against aerosol retrievals from NASA satellite sensors and ground-based measurements. Several possible causes for these common problems of underestimating aerosols in models during the post-monsoon and wintertime periods are identified in particular. These common problems found in multiple models point out directions for future model improvements in this important region.