远离热带风暴中心的大暴雨个例分析  

Analysis of one torrential rain far distant from tropical storm

作　　者：尹东屏[1] 张备[1] 姚丽娜[1] 王啸华[1] 孙秀忠[2] 

机构地区：[1]江苏省气象台,南京210008 [2]北京市气象局,北京100081

出　　处：《气象科学》2011年第6期747-754,共8页Journal of the Meteorological Sciences

基　　金：江苏省重大科技支撑与自主创新示范工程项目(BE2008618);江苏省科技支撑计划-社会发展项目(BE2011818);江苏省气象局科研开放基金(K201006);南京气象雷达开放实验室研究基金(BIG200903)

摘　　要：2010年9月2—3日江苏淮北出现了较罕见的大暴雨过程,暴雨中心雨量为244.7 mm。分析表明,这次大暴雨过程产生在南海登陆的热带风暴"狮子山"倒槽中,暖湿气流在北上中与对流层低层相对冷的气团相遇,在暴雨区产生局地锋生,中层干冷空气的倾斜下侵,促使大气的斜压性增强,不仅产生了对流性不稳定,而且提供了有利于暖湿气流抬升的动力条件。在锋生作用下,气旋性涡度沿锋区发展。在暴雨发生过程中,西行热带风暴倒槽东部的偏南风和副热带高压西部的偏南气流,构成了一支补偿性质的低空急流,向暴雨区输送了充足的暖湿气流。A rare torrential rain with 244.7 mm rainfall in its storm centre has taken place in the north of Jiangsu province from September 2 to 3 in 2010. Analysis shows that this torrential rain process happened in the inverted trough of TS named ＂Lionrock＂, which landed on South China Sea, while warm and wet flow met the colder airmass in the process of northward moving at the bottom of the troposphere.Thus local frontogenesis has occurred in storm area and the dry cold air inclined downward from the mid- dle-level,which reinforced the baroclinicity of atmosphere. This not only caused convective instability, but also supplied the power to lift the warm and wet flow. So that cyclonic vorticity developed along the frontal zone. In this torrential rain process the southerly in the east of inverted trough of westward moving STS and the southern airflow from the east of subtropical high have formed a compensatory lower jet stream, which carried large abundant warm and wet flow to storm area.

关 键 词：远距离热带风暴 暴雨 锋生函数 急流 水汽辐合 

分 类 号：P458.121.1[天文地球—大气科学及气象学]