GRAPES-Meso云分析系统的设计与试验

Design and Experiment of GRAPES-Meso Cloud Analysis System

研究应用LAPS(Local Analysis and Prediction System)云分析方案,基于美国"风暴分析预报中心"开发的中尺度模式ARPS(Advanced Regional Prediction System)的资料分析系统ADAS(ARPS Data Analysis System),开发了GRAPES-Meso(Mesoscale of the Global and Regional Assimilation and Prediction System)区域中尺度数值预报模式的云分析系统,首次实现了地面云观测资料、卫星云图、多普勒雷达反射率资料在GRAPRS模式中的综合同化应用。详尽分析了地面云观测资料、卫星红外云图、可见光云图、多普勒雷达反射率多种观测资料对GRAPES模式初始三维云覆盖、多相混合比等云微物理因子以及初始场的调整。通过对2009年6月28日至7月4日湖南省一次强降水过程的模拟试验检验云分析系统的性能,对比分析表明:(1)云分析系统通过地面云观测资料、卫星红外云图、可见光云图、多普勒雷达反射率的同化,能够反演出三维云覆盖状况;(2)在三维云覆盖的基础上结合云底云顶高度,能够反演出云水、雨水、云冰等微粒,并显著改善模式初始湿度场;(3)云分析系统能够显著缩短模式的热启动时间,明显增大了开始几小时的降水量预报,对24小时的降水预报效果也有显著改善。

For the purpose of applying the surface cloud observation data,satellite images and Doppler radar reflectivity to the GRAPES-Meso（Mesoscale of the Global and Regional Assimilation and Prediction System）model,the GRAPES cloud analysis system has been developed for the first time which is based on the LAPS（Local Analysis and Prediction System）cloud analysis program and referring to ARPS Data Analysis System（ADAS）.The adjustments of the 3D cloud cover and initial field and cloud water and hydrometeors have been analyzed when the surface cloud observation data,satellite images and Doppler radar reflectivity are assimilated in the GRAPES-Meso.A heavy precipitation lasting from June 28 to July 4, 2009 in Hunan is simulated,and the results show：（a）the distribution of 3D cloud cover has been retrieved from the cloud analysis system;（b）the cloud water and hydrometeors have been produced quickly based on the 3D cloud cover and the heights of cloud top and bottom,and also the initial relative humidity field has been adjusted;and（c）the duration of spin-up time has been remarkably decreased,and the fore- cast precipitation has been significantly increased in the early hours,the performance of 24 h precipitation forecast has been also improved obviously.