IMPACTS OF TWO TROPICAL CYCLONES EXPERIENCING EXTRATROPICAL TRANSITION DURING NORTHWARD PROGRESSION ON THE RAINFALL OF LIAODONG PENINSULA

作     者：梁军 陈联寿 李英 朱晶 

作者机构：Dalian Meteorological Observatory Chinese Academy of Meteorological Sciences/LaSW 

出 版 物：《Journal of Tropical Meteorology》 (热带气象学报（英文版）)

年 卷 期：2009年第15卷第1期

页      面：49-53页

核心收录：

学科分类：07[理学] 070601[理学-气象学] 0706[理学-大气科学] 

基　　金：National Key Fundamental Project for Research Development and Plan (2004CB418301) Natural Science Foundation of China (40575018, 40675033) 

主　　题：synoptics typhoon rainstorm diagnostic analysis extratropical transition tropical cyclone Liaodong Peninsula 

摘      要：Both of Typhoon Winnie (9711) and Matsa (0509) underwent an extratropical transition (ET) process when they moved northward after landfall and affected Liaodong Peninsula. However, Matsa produced half as much rainfall as Winnie, although it struck Liaodong Peninsula directly while Winnie passed through the Bohai Sea. The relations between the ET processes and the precipitation over Liaodong Peninsula are examined. The result shows that the precipitation difference between Winnie and Matsa was closely related to the interactions between the westerly systems and typhoons during their ET processes. Winnie was captured by the upper westerly trough and then coupled with it when moving to the mid-latitudes, and the positive anomaly of moist potential vorticity (MPV) was transported downward from the upper troposphere over the remnant circulation of the tropical cyclone (TC). It was favorable to the interaction between tropical warm and wet air and westerly cold air, causing convective cloud clusters to form and develop. The rain belt composed of several meso-β cloud clusters over the Liaodong Peninsula, resulting in heavy rainfall. On the other hand, Matsa did not couple with any upper trough during its ET process and the positive anomaly of MPV in the upper troposphere and its downward transfer were weak. Only one meso-β cloud cluster occurred in Matsa’s rain belt during its ET process that tended to lessen rainfall over Liaodong Peninsula.