A typical stratocumulus precipitation process in the Qilian Mountains in summer was numeri-cally simulated via a numerical model combined with the measured data,revealing the microphysical structure of the cloud system,the water transformation in the cloud and the regional water budget charac-teristics.The results demonstrated the weather research forecasting model's capability of replicating the development of summer cloud systems and the daily fluctuation of precipitation in the Qilian Mountains.The stratocumulus had a high supercooled cloud water content,the maximum of which was 2.6×10-3;sur-face precipitation mainly came from the melting process of snow,accounting for 70.15%,followed by the collision of raindrops with cloud droplet growth and the melting process of graupel particles,account-ing for 13.49%and 12.04%respectively.The formation of snow mainly came from the attachment of snow to supercooled cloud water and the sublimation process of snow,accounting for 61.23%and 37.93%respectively;the net water vapor budget showed a negative value,and there was a large amount of precipitation in the area,indicating that the utilization efficiency of air water resources in the region was relatively low.In order to ensure the ecological environment balance,more importance should be attached to artificial precipitation enhancement.
Qilian Mountainsprecipitationnumerical simulationcloud microphysicwater conversion and budget