Numerical Simulation and Observation Research on the Structure Characteristics of One Convective Cloud Cluster Process

Zhang Yufang; Liu Weiguo; Zhou Yuquan

doi:10.16765/j.cnki.1673-7148.2017.04.002

Abstract：To research the evolution and microphysical characteristics of one convective cloud cluster process happened in Beijing at August 22nd,2015,WRF cloud resolving model coupled with CAMS microphysical scheme is used to simulate this process.Because the scale of the convective cloud cluster is small,which asks for high resolution on time and space,the mesoscale analysis field with high resolution output from LAPS (Local Analysis and Prediction System) is used as initial field of the model.Simulation results is compared to observation data including FY-2F satellite,SA band-Doppler weather radar of Beijing,precipitation data of ground station.At the same time,the microphysical parameters are studied to deeply analyze the precipitation mechanism of this process.The result shows that:the model can well simulate four different evolution stage including production,growth,mature and extinction of the convective cloud cluster process.Whole process maintains about 4 h,and the lifetime of the convective cell which directly influences Beijing stays about 1 h.The simulation of the distribution and evolution of cloud band,the scale,location,shape and vertical structure of the cloud cluster has a good agreement with observation data.The model has the ability to simulate precipitation magnitude and region as well as the location of the strong center.This convective cloud cluster is cold and warm mixed cloud structure and there is abundant supercooled water in the cloud.The precipitation mechanism of this process is a combination of cold cloud precipitation mechanism and the warm's,in which the cold's is the main mechanism,while the water supply in warm cloud has played an enhanced role in precipitation.Melting of the graupel is the main formation of precipitation.