雷达资料在江淮流域暴雨数值模拟中的应用

THE USE OF RADAR DATA IN THE NUMERICAL SIMULATION OF HEAVY RAINFALLS IN THE CHANGJIANG-HUAIHE RIVER BASIN

关键词:  暴雨  雷达回波  数值模拟

Key words:  Radar data  Numerical simulation  Heavy rainfall

摘要:

将雷达资料计入PSU/NCAR中尺度模式,对江淮流域暴雨实例进行了模拟实验、在工作中,雷达资料经过处理加入到模式中,改变初始湿度场分析,然后作24小时数值模拟,并与控制试验作比较。结果表明:加入雷达资料后的数值模拟预报,由于增强了暴雨区及其邻近区域对流层中低层水汽和辐合上升运动,雨区位置和雨量中心值比控制试验更接近实况。

Abstract:

Numerical simulations of two heavy rainfall cases in the Changjiang Huaihe river basin have been camrried with radar data incorporating into the PSU/NCAR mesoscale model. The radar data are used to change initial humidity analysis obtained by conventional radiosound data and then simulations are performed and compared with the control cases. Results show that both of the heavy rainfall distribution and its maximum amounts in sensitivity cases are further improved than those without using radar data. It implies that the enhancement of humidity by radar data and subsequent divergence circulation and ascending motion at the middle and lower troposphere over the rainfall region is essential for improving the results of heavy rainfall numerical simulations.