利用SAWYER-ELIASSEN次级方程对两支雨带的诊断

利用中尺度模式（ Ｍ Ｍ４）模拟的 １９８１ 年 ６ 月 ２７ 日江淮地区梅雨锋暴雨过程的高分辨率资料，使用 Ｓａｗ ｙｅｒ Ｅｌｉａｓｓｅｎ 次级方程，对与雨带相联系的中尺度结构进行了诊断分析。通过模式输出资料进行数值求解，揭示了急流锋生在两支雨带形成和维持中的特殊贡献。分析表明，高、低空急流耦合产生急流锋生环流，锋生环流有利于两支雨带的形成。

DIAGNOSIS OF TWO RAINBANDS DURING A MEIYU FRONT PROCESS WITH SAWYER-ELIASSEN EQUATION

In the previous paper,the Meiyu front torrential rain process in the Jianghuai Basin on 27,June,1981,has been successfully simulated in terms of MM4.The meso scale structure of the systems associated the two rainbands are diagnosed in this paper by using the high resolution modeling data and the Sawyer Eliassen equation,revealing the special contribution of the jet frontogenesis to the formation and maintenance of the rain belts.Analysis shows that the jet frontogenesis circulation is produced by the coupling of the upper and low level jets and favorable for the formation of the two mesoscale rainbelts.