Spatial and temporal distributions of aerosol concentrations and depositions in Asia during the year 2010

Abstract

Aerosol Modeling System (AMS) that is consisted of the Asian Dust Aerosol Model2 (ADAM2) and the Community Multi-scale Air Quality (CMAQ) modeling system has been employed to document the spatial distributions of the monthly and the annual averaged concentration of both the Asian dust (AD) aerosol and the anthropogenic aerosol (AA), and their total depositions in the Asian region for the year 2010. It is found that the annual mean surface aerosol (PM10) concentrations in the Asian region affect in a wide region as a complex mixture of AA and AD aerosols; they are predominated by the AD aerosol in the AD source region of northern China and Mongolia with a maximum concentration exceeding 300μgm−3; AAs are predominated in the high pollutant emission regions of southern and eastern China and northern India with a maximum concentration exceeding 110μgm−3; while the mixture of AA and AD aerosols is dominated in the downwind regions extending from the Yellow Sea to the Northwest Pacific Ocean. It is also found that the annual total deposition of aerosols in the model domain is found to be 485Tg (372Tg by AD aerosol and 113Tg by AA), of which 66% (319Tg) is contributed by the dry deposition (305Tg by AD aerosol and 14Tg by AA) and 34% (166Tg) by the wet deposition (66Tg by AD aerosol and 100Tg by AA), suggesting about 77% of the annual total deposition being contributed by the AD aerosol mainly through the dry deposition process and 24% of it by AA through the wet deposition process. The monthly mean aerosol concentration and the monthly total deposition show a significant seasonal variation with high in winter and spring, and low in summer.