资源环境科技发展态势分析平台

Aerosols can modulate the convective cloud-precipitation system in complex ways, which was rarely investigated in North China during the heavily polluted autumn and winter. In this study, the relationships between aerosol pollution and convective precipitation in the North China Plain (112 to 116°E, 36 to 42°N) during autumn and winter were elucidated by combining the data of Global Precipitation Measurement Dual-Frequency Precipitation Radar (GPM-DPR) and the Modern-Era Retrospective Analysis for Research and Applications, Version 2 (MERRA-2). A positive correlation was found between the aerosol optical depth (AOD) and convective rain rate (RR). Comparative analyses between polluted and clean conditions were conducted to understand this AOD-RR relationship. Higher droplet concentration with smaller size were noted under the polluted condition, associated with higher latent heat released, implying that the increased aerosols may favor the development of the convective cloud-precipitation system through the “aerosol invigoration effect”. Besides, the impacts of ambient meteorological conditions on the AOD-RR relationship were also analyzed. It was found that correlations between AOD and RR were always positive in the studied region, irrespective of precipitable water vapor, lower tropospheric stability, and wind shear. A stronger AOD-RR correlation can be found when the lower tropospheric stability or wind shear becomes weaker. Our work provided evidence on the invigoration effect of aerosol during the heavily polluted months in North China, which may improve the understanding of the complex interactions between aerosol and precipitation.