摘要
利用逐日NCEP再分析常规观测资料、逐小时自动站资料和卫星云图资料,对2010年7月14—18日发生在四川盆地的大暴雨天气过程进行诊断分析,重点探讨了台风活动对大尺度环流背景、西南低涡形成与维持、水汽及能量输送的作用。结果表明:(1)本次暴雨是在副热带高压、台风、西南低涡等多个不同尺度系统相互作用下发生的;(2)台风环流东侧偏南气流和副高西侧偏南气流长时间的融合贯通,一方面有利于"鞍"型场大尺度环流背景稳定和低层西南涡的发展及维持;另一方面两支气流叠加构成输送带,将低纬大量水汽和热量向暴雨区上空输送,有利于暴雨区上空水汽的积聚及形成高能不稳定区;冷暖空气交绥于暴雨区,促使不稳定能量释放,形成大暴雨天气。
A composite analysis is performed of the July 15 storm rainfall in S ichuan province during 14--18 July 2010 based on NCEP reanalysis data, dense observational data and satellite data. Intensive discussions are made about the effects of the typhoon on the general circulation background, the formation and maintenance of the southwest vortexes and the transportation of water vapor and energy. The results show as follows. （1） The storm rainfall is caused by the interactions of multiscale weather systems, including the subtropical high, tropical depressions and southwest vortexes. （2） On one hand, the sustained confluences of the southern air flows from the eastern part of the typhoon and the western part of the subtropical high are beneficial to the stability of a saddle-pattern circulation background and development of the southwest vortexes. On the other, abundant water vapor and energy are transported from low-latitude areas to storm rainfall regions by the converging southern air flows, which are favorable for the accumulation of water vapor and unstable energy. Cold air and warm air are mixed up over the rainstorm area, which stimulates the convection and leads to the heavy storm.
出处
《热带气象学报》
CSCD
北大核心
2013年第1期169-176,共8页
Journal of Tropical Meteorology
基金
西南区域气象中心重大科研业务项目(2010-5)
公益性行业(气象)科研专项(GYHY200906001)
中国气象局预报员专项(CMAYBY2011-046)共同资助
关键词
台风“康森”
四川大暴雨
西南低涡
相互作用
水汽和能量输送
typhoon Conson
storm rainfall in Sichuan
southwest vortexes
interaction
transfer of watervapor and energy
