Evolution of the Mid-tropospheric Vortex during the Formation of Super Typhoon Megi(2010)  

作　　者：Li ZHUO Dexian FANG Zheng WU Juan FANG 

机构地区：[1]Key Laboratory of Mesoscale Severe Weather(MOE),School of the Atmospheric Sciences,Nanjing University,163 Xianlin Road,Nanjing 210046,China [2]Yubei Meteorological Office of Chongqing,Chongqing 401147,China [3]Chongqing Institute of Meteorological Sciences,Chongqing 401147,China

出　　处：《Advances in Atmospheric Sciences》2020年第7期751-765,共15页大气科学进展（英文版）

基　　金：supported in part by the National Key Research and Development Program of China(Grant No.2017YFC1501601);the National Natural Science Foundation of China(Grant No.41875067)。

摘　　要：As a follow-up of a previously published article on the contribution of tropical waves,this study explores the evolution of the mid-tropospheric mesoscale cyclonic vortex(MV)during the formation of Typhoon Megi(2010)with a successful cloud-resolving simulation.It is found that the formation and intensification of the MV were related to the deep convection and subsequent stratiform precipitation,while the weakening of the MV was related to the shallow convection.Both the upward transport of vorticity related to the deep convection and the horizontal convergence associated with the stratiform precipitation contributed to the formation and intensification of the MV.Even though the latter was dominant,the former could not be ignored,especially in the early stage of the MV.The MV played dual roles in the formation of Megi.On the one hand,the formation and intensification of MV were primarily associated with the stratiform precipitation,which induced the low-level divergence inhibiting the spin-up of the near-surface cyclonic circulation.On the other hand,the coupled low-level cold core under the MV benefited the accumulation of the convective available potential energy(CAPE),which was favorable for the convective activity.A sensitivity experiment with the evaporative cooling turned off indicated that the development of the MV retarded the genesis process of Megi.

关 键 词：TYPHOON SHALLOW DIVERGENCE 

分 类 号：P444[天文地球—大气科学及气象学]