摘要
通过对 971 1号台风登陆北上穿过山东造成山东特大暴雨过程的湿位涡的分析 ,并从湿位涡的角度研究了台风演变及山东特大暴雨的形成机制 ,揭示了冷空气在台风演变及暴雨过程中的重要作用。结果表明 :倾斜涡度发展是暴雨产生和台风加强的重要机制之一 ,暴雨产生在 θe线陡立密集区内 ;湿位涡在这次暴雨过程中对流层低层具有 MPV1 <0 ,MPV2 >0的特征 ,此次暴雨产生在负的MPV1等值线密集区中 ;对流层上部及平流层下部高位涡的下传使得低层斜压性增大 ,引起低层的对流稳定度减小 ,促使气旋性涡度发展 ,有利于位势不稳定能量的释放 ,使得暴雨增幅 ,导致台风的加强并演变为温带气旋。
Based on the analysis of moist potential vorticity(MPV) for the typhoon 9711 that caused rainstorm in Shandong Province,we studied the mechanism of the typhoon evolution and the rainstorm in Shandong Province from the viewpoint of MPV and disclosed the important effect of the cold air inflow.The results show that slantwise vorticity development is an important mechanism of the rainstorm and typhoon intensification.The rainstorm occurred in the stiff and dense section of moist isentropes. MPV1<0 and MPV2>0 were characteristic of low-tropospheric MPV in the rainstorm area and the rainstorm occurred in the dense section of the negative isolines of MPV1. The downward spread of high MPV from the upper troposphere and lower stratosphere intensified the baroclinity and decreased the convective stability at low levels, causing the vortex to develop.It is also beneficial to the release of instability energy, resulting in rainstorm amplification and typhoon evolution.
出处
《中国海洋大学学报（自然科学版）》
CAS
CSCD
北大核心
2004年第1期13-21,共9页
Periodical of Ocean University of China
基金
山东省气象中心自立课题资助
关键词
台风演变
暴雨过程分析
位涡诊断
温带气旋
倾斜涡度发展
typhoon rainstorm
potential vorticity
slantwise vorticity development
extratropical cyclone
