摘要
根据湿位涡（MPV）理论分析了1991年7月5～6目的暴雨过程中700hP高度上的湿位涡垂直部分MPV1和水平部分MPV2。结果显示，MPV1和MPV2的分布特征同对流层低层造成暴雨的天气系统──中尺度气旋的发展演变有很好的对应关系；MPV1＞0，MPV2＜0且｜DMPV1｜≥｜DMPV2｜的环境大气有利于对称不稳定出现；计算表明，这次过程的对流层中低层确有对称不稳定区域存在，它对暴雨及其系统的发展起了重要作用。
Based on the moist potential vorticity (MPV) theory,this paper analysed the vertical and horizontal components of MPV,MPV1 and MPV2,on 700hPa for the torrential rain process occured during 5 - 6 July, 1991 in the Changjiang-Huaihe Basin. The results showed that the distributions of MPV1 and MPV2 were consistent with the development of low-level mesoscale cyclonic circulation that was caused the torrential rain- It is favourable to develop symmetric instability when MPV1 >0,MPV2<0 and | MPV1 |≥ | MPV2 |. The symmetric instability intensified the torrential rain.
出处
《气象科学》
CSCD
北大核心
2000年第2期171-178,共8页
Journal of the Meteorological Sciences
基金
国家自然科学基金
关键词
湿位涡
对称不稳定
暴雨
降水过程分析
Moist potential vorticity (MPV)
Symmetric instability
Torrential rain
