2011年9月华西秋雨特征及成因分析  

Analysis of Features and Physical Mechanisms of 2011 Autumn Rainfall in West China

作　　者：蔡芗宁 康志明 牛若芸 鲍媛媛 

机构地区：[1]国家气象中心,北京100081

出　　处：《气象》2012年第7期828-833,共6页Meteorological Monthly

基　　金：国家重点基础研究发展计划(973计划)项目(2012CB417204);中国气象局预报员专项(CMAYBY2012-072)共同资助

摘　　要：本文分析了2011年9月华西秋雨的时空分布特征和大尺度环流形势,并对秋雨形成的主要物理机制进行了诊断分析。结果表明:2011年9月华西地区北部降雨日数多、强度大、持续时间长、落区集中。9月上中旬500hPa高度场上巴尔喀什湖以北的高压脊稳定维持,脊前西北气流携带的冷空气与副高外围的东南暖湿气流和来自孟加拉湾北上的西南暖湿气流交汇于华西地区北部,造成了该地区长时间的持续性强降雨。华西地区北部处于高低能量之间的强能量锋区中,东路干冷空气的汇入。The space-time distribution features and large-scale atmospheric circulation of the 2011 autumn rainfall in West China are analyzed to study the physical mechanisms of autumn rainfall. The results show that there were more rainy days, stronger raining processes and longer duration than normal in northernWest China in September 2011. The 500 hPa circulation analysis shows that there was a quasi-stationary ridge near Lake Balkhash, from which the cold air was combined constantly with the warm and humid southeast air in the southwest side of the subtropical high and with the southwest air from the Bay of Ben-gal. The physical analysis shows that there was a strong energy frontal zone in the north of West China, which was strengthened because the cold air from the east area entered so that the instability energy burst out, thus triggering the rainstorm in West China.

关 键 词：华西秋雨 环流形势 物理机制 

分 类 号：P429[天文地球—大气科学及气象学]