【作者】 郑秀云； 王建捷； 何金海； 刘勇；

【Author】 Zheng Xiuyun1 Wang Jianjie2 He Jinhai1 Liu Yong3 (1.Nanjing University of Information Science&Technology, Nanjing 210044;2.National Meteorological Center, Beijing 100081;3.Anhui Weather Office, Hefei 230061)

【机构】 南京信息工程大学； 国家气象中心； 安徽省气象台；

【摘要】 利用常规和多种高分辨率的非常规观测资料,分析了2003年7月3～4日淮河流域大暴雨过程中安徽省北部暴雨雨团的活动及与之相联系的中尺度对流系统的发展演变特征。结果表明:在有利的大尺度环流背景下,梅雨锋中-α尺度云系中的中-β尺度对流系统的发生发展是导致暴雨的直接原因。暴雨强度和出现地点与中-β尺度扰动密切相关,整个暴雨过程有3次生命史不完全相同的雨团活动期,对应着三次雨强峰值;不同雨团活动期内,中-β尺度对流系统的组织发展形式有所不同,第一次和第三次雨团活动是由几个相对分散的块状中-β尺度对流复合体相继影响所致,而第二次雨团活动则与长约100km的近地层中-β尺度辐合线的迅速发展相联系;中-β尺度对流云团的生命史与雨团的生命史并不一定相同。本次暴雨过程中,起主要作用的是嵌在絮状回波里的一个个对流复合体和个别强对流单体;回波强度和强回波发展高度与地面降水强度呈正相关。更多还原

【Abstract】 The meso-scale characteristics of the torrential rainfall case of 3～4th July 2003 over Huaihe Valley was investigated by using conventional radiosonde and surface observation as well as high resolution observation data. It is revealed that the development of meso-β-scale convective systems within the meso-α-scale cloud belt of the Mei-Yu front results in directly the torrential rainfall over Huaihe Valley under the favorable large-scale circulation conditions. There are three rain-mass active periods corresponding to three different peak values of rainfall intensity in the time series of the rainfall case. The rain-mass activities in the first and the third periods are related to the continuous affection of the dispersive meso-scale convective complexes, while rain-mass activity in the second period is caused by the rapid development of the near surface meso-β-scale (about 100km long) convergence line, which induces the rapid and systematic development of convective cloud cells into meso-β-scale complexes. It is also shown that these meso-β-scale convective complexes are with strong reflectivity echoes (about 40 to 60dBZ) in the meddle to low atmosphere, and there are positive correlations between the echo intensities, vertical extensions of the meso-β-scale convective complexes and the surface precipitation intensities.更多还原