2015年湖北省梅雨期一次暴雨过程对流云活动分析  

Analysis of the evolution of convective clouds during a rainstorm in 2015 over Hubei province

作　　者：张端禹[1] 崔春光[1] 徐明[1] 王婧羽 胡昌琼 

机构地区：[1]中国气象局武汉暴雨研究所暴雨监测预警湖北省重点实验室,湖北武汉430205 [2]湖北省气象服务中心,湖北武汉430205

出　　处：《气象与环境学报》2017年第2期8-17,共10页Journal of Meteorology and Environment

基　　金：国家自然科学基金项目(41375057);灾害天气国家重点实验室开放课题(2014LASW-A05);湖北省气象局科技发展基金项目(2016Q04);暴雨监测预警湖北省重点实验室暴雨研究开放基金项目(IHR201401)共同资助

摘　　要：利用常规与加密气象观测资料、FNL再分析格点资料及FY-2G卫星云顶亮温(Temperature of Black Body,TBB)观测资料,对2015年7月14—15日湖北省梅雨期一次连续暴雨过程对流云活动的环境条件和导致短时强降雨的对流云影响方式进行了分析。结果表明:500 hPa位于西风槽前、850 hPa风场辐合、温度露点差较小及850—500 hPa暖平流为有利于湖北省对流云活动的环境条件。当天气尺度暖输送带云系在江南西部至长江中游地区建立,且低层暖切变线同时出现在湖北地区上空时,降雨明显增幅;当暖输送带云系明显东移后,湖北地区暴雨过程结束。当暖输送带位于湖北地区上空时,850 hPa相当位温平流项和对流项均为较大正值,且对流项大值区出现在平流项大值区的南侧。短时强降雨主要发生在降雨盛期,是构成湖北地区暴雨的重要组成部分。湖北省短时强降雨的4种对流云影响方式分别为对流云团西边界、深对流云团中心区、对流云串"列车效应"及对流云合并加强;其中,受对流云西边界、深对流云中心区或云团串影响的短时强降雨发生次数较多,受深对流云中心区和对流云合并加强影响的短时强降雨平均降雨量较大。Conventional and intensive observation data, hourly rainfall data, FNL reanalysis data, as well as the Temperature of Black Body （TBB） observed by FY-2G satellite were used to analyze the environmental condi- tions and affecting mechanisms of convective clouds during a Meiyu rainstorm on July 14 to 15,2015 over Hubei province. The results show that the favorable conditions for the evolution of convective clouds are convective clouds located in front of the trough at 500 hPa, wind converging and small dew point depression at 850 hPa and warm advection maintaining between 500-850 hPa. When synoptic scale Warm Conveyor Belt （WCB） clouds de- velop from western Jiangnan area to the middle reaches of Yangtze River, and low-level warm shear lines appear o- ver Hubei province, the precipitation will increase significantly. When WCB clouds obviously move eastward, rain- storm over Hubei province will terminate. When WCB is located over Hubei province,large positive items of both advection and convection of equivalent potential temperature will appear at 850 hPa, and the areas with large con- vection items will appear to the south of those with large advection items. Short-time heavy precipitation occurs predominantly in the rain-prevailing period, which is important to local rainstorms. There are four mechanisms in- fluencing short-time rainstorms over Hubei province,including the western borders of convective clouds, center ar- eas of deep convective clouds,＂ train effect＂ of convective cells and mergence of convective clouds. The number of rainstorms affected by the western borders of convective clouds and convective cells is relatively more, and the precipitation affected by center areas and mergence of convective clouds is relatively larger.

关 键 词：对流云 暖输送带 短时强降雨 亮温梯度 西边界 列车效应 

分 类 号：P458.121.1[天文地球—大气科学及气象学]