Mesoscale Modeling Study of Severe Convection over Complex Terrain

作     者：Ying ZHANG Zhiyong MENG Peijun ZHU Tao SU Guoqing ZHAI 

作者机构：Department of Atmospheric SciencesSchool of Earth SciencesZhejiang University Department of Atmospheric and Oceanic SciencesSchool of PhysicsPeking University 

出 版 物：《Advances in Atmospheric Sciences》 (大气科学进展（英文版）)

年 卷 期：2016年第33卷第11期

页      面：1259-1270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：Sponsored by the National (973) Program on Key Basic Research project entitled "Observation,Prediction and Analysis of Severe Convection of China" (Grant No. 2013CB430104) the National Natural Science Foundation of China (Grant No. 41575047) 

主　　题：convective convection divergence mesoscale mountains instability southwestern terrain moved uplift 

摘      要：Short squall lines that occurred over Lishui, southwestern Zhejiang Province, China, on 5 July 2012, were investigated using the WRF model based on 1°× 1° gridded NCEP Final Operational Global Analysis data. The results from the numerical simulations were particularly satisfactory in the simulated radar echo, which realistically reproduced the generation and development of the convective cells during the period of severe convection. The initiation of this severe convective case was mainly associated with the uplift effect of mesoscale mountains, topographic convergence, sufficient water vapor, and enhanced low-level southeasterly wind from the East China Sea. An obvious wind velocity gradient occurred between the Donggong Mountains and the southeast coastline, which easily enabled wind convergence on the windward slope of the Donggong Mountains; both strong mid–low-level southwesterly wind and low-level southeasterly wind enhanced vertical shear over the mountains to form instability; and a vertical coupling relation between the divergence on the upper-left side of the Donggong Mountains and the convergence on the lower-left side caused the convection to develop rapidly. The convergence centers of surface streams occurred over the mountain terrain and updrafts easily broke through the lifting condensation level（LCL） because of the strong wind convergence and topographic lift, which led to water vapor condensation above the LCL and the generation of the initial convective cloud. The centers of surface convergence continually created new convective cells that moved with the southwest wind and combined along the Donggong Mountains, eventually forming a short squall line that caused severe convective weather.