我国中部区域人工增雨天气系统分型及典型天气系统特点

利用常规气象观测资料、自动站观测资料和探空资料等,对所选取的2004—2013年共78例降水过程进行分析,将中部区域春秋季降水过程分为3个类型:低槽/切变线冷锋型、低涡(西南涡/西北涡)气旋型、低槽/切变线冷高压型。统计结果表明,中部区域春秋季降水出现概率最多的类型依次为切变线冷锋型、低槽冷锋型和西南涡类型,各天气类型的雨区移动方向均以自西向东为主,低层700 h Pa和850 h Pa多存在西南或偏南急流,水汽主要来自于孟加拉湾。分析中部区域3种主要降水类型特征及其增雨潜力区位置发现:1)低槽冷锋类型降水一般出现在500 h Pa和700 h Pa低槽前部、地面冷锋后部,多为连续性降水;其增雨潜力区主要位于500 h Pa低槽前部、700h Pa槽前和西南急流出口区的左侧,以及地面冷锋后部或锋线附近区域。2)切变线冷锋类型降水多出现在地面冷锋后部、低层切变线两侧附近;其增雨潜力区主要位于700 h Pa和850 h Pa两切变线之间且较靠近700 h Pa切变线一侧、急流出口左侧的带状区域。3)西南涡波动类型降水一般出现在低涡中心及700 h Pa暖式切变线两侧附近,降水持续时间较长;其增雨潜力区主要位于700 h Pa和850 h Pa低涡中心附近及暖式切变线北侧区域。

Weather System Types and Typical Characteristics of Artificial Precipitation Enhancement in Central Area of China

Using conventional meteorological observational data,automatic weather station observational data and radiosonde data,the selected 78 precipitation processes from 2004 to 2013 were analyzed,three weather types of the spring and autumn period precipitation in central area were obtained: low trough/shear line cold front,vortex(SW vortex/NW vortex) cyclone,low trough/shear line cold anticyclone.The results showed that the highest occurrence probability order of the spring and autumn precipitation types in central area were shear line cold front,low trough cold front and SW vortex.The moving direction of most precipitation processes were from the west to east,there were southwest or south jet on 700 hPa and 850 hPa,the water vapor mainly came from the Bay of Bengal.Analysis of the characteristics of three main weather types in central area and position of the precipitation enhancement potential area show as follows.1)The precipitation of low trough cold front type generally occurs in the front of the trough of 500 hPa and 700 hPa,the back of the ground cold front,mostly continuous precipitation.The precipitation enhancement potential area is mainly located in the front of the trough of 500 hPa and 700 hPa,the left of the southwest jet exit area,and near or back of the ground cold front.2)The precipitation of shear line cold front type occurs in the back of the cold front,near the both sides of the low level shear.The precipitation enhancement potential area is mainly located between two shear lines on 700 hPa and 850 hPa and closer to the side of the 700 hPa shear line,and the left of the jet exit strip area.3)The precipitation of SW vortex type appears near the vortex center and both sides of the warm shear on 700 hPa,which continues for a long time.The precipitation enhancement potential area is mainly located near the vortex center of the 700 hPa and 850 hPa,and the north side area of the warm shear line.