Examination of aerosol impacts on convective clouds and precipitation in two metropolitan areas in East Asia; how varying depths of convective clouds between the areas diversify those aerosol effects?

Abstract. This study examines the role played by aerosols in the development of clouds and precipitation in two metropolitan areas in East Asia that has experienced substantial increases in aerosol concentrations over the last decades. These two areas are the Seoul and Beijing areas and the examination has been done by performing simulations using a cloud-system resolving model (CSRM). Aerosols are advected from the continent to the Seoul area and this increases aerosol concentrations in the Seoul area. These increased aerosol concentrations induce the enhancement of condensation that in turn induces the enhancement of deposition and precipitation amount in a system of less deep convective clouds as compared to those in the Beijing area. In a system of deeper clouds in the Beijing area, increasing aerosol concentrations also enhance condensation but reduce deposition. This leads to aerosol-induced negligible changes in precipitation amount. Also, in the system, there is a competition for convective energy among clouds with different condensation and updrafts. This competition results in different responses to increasing aerosol concentrations among different types of precipitation, which are light, medium and heavy precipitation in the Beijing area. In both of the areas, aerosol-induced changes in freezing play a negligible role in aerosol-precipitation interactions as compared to the role played by aerosol-induced changes in condensation and deposition.