我国西南地区一次暴雨过程特征及成因  

Cause analysis and characteristics of a rainstorm in the southwest area of China

作　　者：井喜[1,2] 屠妮妮[3] 曾鹏 李明娟[5] 叶成志 杜小玲 井宇[5] 李栋梁[8] 

机构地区：[1]中国气象科学研究院灾害天气国家重点实验室,北京100081 [2]榆林市气象局,陕西榆林719000 [3]中国气象局成都高原气象研究所,四川成都610071 [4]广西壮族自治区气象台,广西南宁530022 [5]陕西省气象局,陕西西安710015 [6]湖南省气象局,湖南长沙410007 [7]贵州省气象局,贵州贵阳550002 [8]南京信息工程大学,江苏南京210044

出　　处：《大气科学学报》2011年第6期725-736,共12页Transactions of Atmospheric Sciences

基　　金：中国气象科学研究院灾害天气国家重点实验室基金资助项目(2007LASW10)

摘　　要：利用卫星云图、多普勒天气雷达资料和高空风等各种天气学资料,对2009年6月8—9日广西、贵州、以及和湖南交界地带的一次暴雨过程进行了综合分析。结果表明,暴雨是由中尺度对流复合体东移、β中尺度强对流云团发展、以及二者合并造成的;地面α中尺度低压带配合α中尺度纬向切变线的生成,为中尺度对流复合体(mesoscale convective complex,MCC)的东移发展、β中尺度强对流云团的发展、以及二者的合并创造了有利条件;地面能量比低值舌的活动是MCC和β中尺度强对流云团生成和发展的触发机制之一;在多普勒雷达径向速度图上,MCC的生成和发展,伴随西南低空急流的建立和维持,大范围的逆风区的生成;MCC的消亡,伴随西南低空急流的减弱和消失,对应西北气流建立和东扩。MCC发展期和β中尺度强对流云团发展期、MCC消散期和β中尺度强对流云团消散期的涡度收支以及视热源和视水汽汇有很大的不同。By using the synoptic data such as satellite image,Doppler radar and upper wind,a rainstorm occurring in Guangxi and Guizhou as well as the southwest area of Hunan province on June 8—9,2009 is analyzed.The results show that the storm was caused by the eastward moving MCC（mesoscale convective complex） and the development of β mesoscale strong convective cloud cluster and the mergence of them.The α mesoscale low pressure belt,together with the α mesoscale shear line on the ground surface,provided the conditions for MCC＇s movement to the east and β mesoscale strong convective cloud cluster＇s development and their mergence.The low tongue of the surface energy ratio was one of the triggers of the generation and development of MCC and β mesoscale strong convective cloud cluster.In the Doppler Radar vertical velocity diagram,the generation and development of MCC was accompanied by the establishment and maintenance of the southeast low jet stream and the generation of wide range of dead wind area.The MCC＇s extinction together with the weakening and vanishing southeast low jet stream,were in accordance with the generation and eastward movement of the northwest air stream.Studies also show that the budget of vorticity and the equilibrium of heat and vapour were very different during the development and vanishing periods of MCC and β mesoscale strong convective.

关 键 词：中尺度对流复合体 β中尺度强对流云团 暴雨 涡度收支 

分 类 号：P458.121.1[天文地球—大气科学及气象学]