梅雨锋生次级环流对暴雨的作用

THE EFFECTS OF THE FRONTAL SECONDARY CIRCULATION ON THE HEAVY RAIN OF MEIYU FRONT

本文采用了MM4中尺度数值模式对1991年7月5日08时至6日20时发生在江淮流域的梅雨锋暴雨过程进行了模拟。在模拟较理想的基础上，利用模式输出的高分辨率的动力协调资料，就暴雨过程中锋生次级环流各强迫项对暴雨的作用进行了诊断研究。结果表明：锋生次级环流对暴雨形成具有重要的作用，但在暴雨过程不同时期各项的作用差异很大。

The mesoscale numerical model MM4 was used to simulate the heavy rain process asso-ciated with Meiyu front occurred in the Changjiang-Huaihe Basin during the period from08: 00 July 5 to 20: 00 July 6, 1991．The hourly model products with high spatial and temperalresolution were then used for detailed diagnosis studies of the frontal secondary circulation.The results showed that the frontal secondary circulation played an important role in the for-mation of the heavy rain. But different forcing factor had different relative importance in eachdevelopment period of the heavy rain.