大西洋和印度洋上空"射线状"云的观测分析与数值模拟研究OA北大核心CSTPCD

In this paper a total of 118 Actinoform Clouds over the Atlantic and Indian Oceans from 2017 to 2021 were statistically analyzed by using satellite visible cloud imagery provided by MODIS sensors and VIIRS sensors.WRF(Weather Research and Forecasting)model was also employed to investigate an Actinoform Cloud case over the South Atlantic on 8 July,2019 by using horizontal resolution of 1 km modeling results.The vertical structures of cloud condensation nuclei,air temperature,vertical velocity,water vapor mixing ratio and horizontal distribution of water vapor mixing ratio of the Actinoform Clouds were analyzed based on WRF modeling results.Actinoform Cloud is a meso-scale weather phe-nomenon mainly occurring over low-latitude region and mostly occurring over the Southern Hemisphere Oceans.Summer and autumn are seasons of frequent occurrence of Actinoform Clouds over the Atlantic and Indian Oceans.WRF modeling results show that each cloud arm of Actinoform Clouds corresponds to varying degrees of upward motion,and Actinoform Cloud is a convective cloud in nature.Atmospheric inversion layer will limit the higher development of cloud top,and water vapor is confined below the inversion layer.The wider inversion layer is an important factor for shaping the structure of Actinoform Cloud.