基于CloudSat卫星资料对中亚低涡暴雨个例的诊断分析和数值模拟

Diagnostic analysis and numerical simulation of a Central Asian vortex rainstorm based on CloudSat satellite data

利用ECMWF再分析资料作为初始场和边界条件,用WRF(weather research and forecasting model,WRF)模式对新疆地区中亚低涡暴雨个例进行模拟,结合区域自动气象站每小时降水数据、CloudSat卫星2B-CWC-RO数据产品和FY-2E卫星TBB资料评估Lin方案、WSM 6方案、Thompson方案和WDM 6方案在新疆地区的适用性。结果表明:Thompson方案在小雨(0.1~5.0 mm)和中雨(5.1~10.0 mm)的12 h累积降水模拟中占有优势。4种云微物理参数化方案模拟的云顶亮温分布图均与FY-2E卫星观测十分相似,但在数值上均低于观测。从CloudSat剖面平均冰水含量的垂直分布情况看,Thompson方案模拟冰水含量在数值和高值区的高度上模拟效果最好,Lin方案的模拟效果最差。从3 km区域平均冰水含量的垂直分布情况看,Thompson方案模拟的云冰含量最高,WSM 6方案与WDM 6方案模拟的云冰含量次之,且两者的冰水含量-高度廓线图几乎重合,Lin方案模拟的云冰含量最低。

A Central Asian vortex rainstorm episode was simulated using the Weather Research and Forecasting model based on reanalysis data from the European Centre for Medium-Range Weather Forecasts.Hourly precipitation data from regional automatic weather stations,CloudSat satellite 2B-CWC-RO data,and FY-2D/E satellite TBB(Black Body Temperature)data were used to evaluate the applicability of the Lin,WSM 6,Thompson,and WDM 6 schemes in forecasting precipitation in Xinjiang.The results were as follows:the Thompson scheme was superior in the simulation of light rain(0.1-5.0 mm)and moderate rain(5.1-10.0 mm).The distribution of the cloud top bright temperature simulated using the four schemes was similar to,though slightly lower than,that measured by FY-2E satellite observation.According to the vertical distribution of the average ice content measured by CloudSat observation,the Thompson scheme was also superior in the numerical simulation of ice content and height in the high-value region;the Lin scheme performed worst in these areas.According to the vertical distribution of average ice content in a 3 km area,the cloud ice content simulated with the Thompson scheme was the highest,followed by the WSM 6 and WDM 6 schemes,and finally the Lin scheme.The ice content-height profile of the WSM 6 and WDM 6 schemes were almost coincident.