提利用高分辨率GRAPES Meso中双参数云微物理方案，对我国两次强降水过程进行数值模拟，并与模式中 WSM6和NCEP5方案进行对比分析，结合多种观测资料，诊断评估方案的预报性能，同时研究伴随强对流性降水中的关键云物理过程。个例研究表明，对流发展旺盛的云团中，冰相粒子尤其是霰粒子对对流的发展与降水起着主导作用，霰的融化是强降水的主要来源，而周围的层状云区域霰粒子的分布极少，主要受雪的融化与暖云降水的影响。双参数方案模拟的雨带走向、范围和降水强度与实况拟合较好，同时在对流单体的最大回波高度与强度、冰晶的分布与云砧结构等方面也具有一定优势，但冰晶含量和回波顶高度略低于观测，这都为双参数方案的优化与业务应用提供重要的支持。%In this study,two heavy precipitation processes are simulated using the two-moment cloud mi-crophysical scheme coupled with high-resolution GRAPES model.The scheme is compared with WSM6 scheme,NCEP5 scheme and a variety of observation data to diagnose the prediction performance and ana-lyze the key cloud microphysics process in deep convective precipitation.The simulation study shows that ice phase particles,especially graupel particles,play a leading role on the convection and precipitation in the deep convection clouds and the melting of graupel is the main source of heavy precipitation,while grau-pel distributes rarely in the stratiform precipitation region which is mainly affected by the melting of snow and warm cloud precipitation.The results derived from the two-moment scheme fit better with observa-tions on rain belt direction,precipitation range and intensity.The scheme also has certain advantages on the maximum echo height and strength of convective cells,ice content distribution and cloud anvil struc-ture.However,the ice content and echo height are slightly lower than observations.All these results would provide meaningful support for the improvement and operational application of the two-moment scheme.
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