2019年7月17日江苏东南部特大暴雨的双偏振雷达观测分析  

Microphysical characteristics of the extremely heavy rainstorm observed by Jiangsu polarimetric radars network in southeastern Jiangsu on July 17,2019

作　　者：王坤 王啸华 夏昕[4] 李敏 顾沛澍 彭小燕 WANG Kun;WANG Xiaohua;XIA Xin;LI Min;GU Peishu;PENG Xiaoyan(Nantong Meteorological Bureau,Jiangsu Nantong 226000,China;Key Laboratory of Transportation Meteorology,CMA,Nanjing 210041,China;Jiangsu Meteorological Observatory,Nanjing 210041,China;Shenzhen National Climate Observatory,Shenzhen Meteorological Bureau,Shenzhen 518000,China;Haimen Meteorological Bureau,Jiangsu Nantong 226100,China)

机构地区：[1]南通市气象局,江苏南通226000 [2]中国气象局交通气象重点开放实验室,南京210041 [3]江苏省气象台,南京210041 [4]深圳市国家气候观象台,广东深圳518000 [5]海门区气象局,江苏南通226100

出　　处：《气象科学》2022年第5期610-621,共12页Journal of the Meteorological Sciences

基　　金：国家自然科学基金资助项目(U2142203);中国气象局预报员专项(CMAYBY2020-045);北极阁开放研究基金(BJG202211);深圳市可持续发展科技专项项目(KCXFZ20201221173610028)。

摘　　要：利用S波段双偏振雷达数据,结合再分析数据、自动气象站、探空和二维闪电探测数据,采用多普勒雷达风场反演和粒子相态识别等方法,分析了2019年7月17日江苏省东南部多站破历史记录的超强降水对流风暴的偏振特征和云微物理特征;并选取了打破当地强降水历史记录如皋站和潞城站,分析了影响两站的对流单体的异同。影响如皋的对流风暴几无闪电活动,对流质心接近地面,上升气流相对较弱。且0℃和-35℃层间霰粒子数目相对较少,闪电几乎不存在。在融化层以下,由于强烈的暖雨过程,较大的冰相粒子落下并融化和低层雨滴的聚并增长,导致低层雨滴数量迅速增加,带来地面极端强降水。潞城地区雷暴活动明显,影响其对流风暴发展旺盛。-35~0℃层存在强烈的上升运动,抬升低层大量的液相粒子通过淞附作用形成的霰,并与高层冰晶不断碰撞,在云层中形成强大的电场,产生强烈的负闪,且在地面产生了极强的降水。这表明融化层以上的冰相微观物理过程,对于降水的发生和增强非常重要。The microphysics and kinematics of this heavy rainstorm event was analyzed by using algorithms such as Doppler radar wind field inversion and hydrometeor identification algorithm based on the combination of data from polarimetric S-band radars network,reanalysis data,2-D lightning detection data and observational data from automatic weather stations,laser-optical Particle Size Velocity instrument,as well as sounding,The convective storms,which leading to record-breaking heavy precipitation in Rugao and Lucheng,were selected separately for comparative analysis.Regarding the convective storm affecting Rugao,convective storm extension height was relatively low,and the center of mass was seen closed to the ground.Moreover,the number of graupel particles between the layers at 0 ℃ and-35 ℃ was relatively small,and lightning could be hardly seen.This convective storm was a system of typical warm clouds with very high precipitation efficiency,which caused high concentration of raindrops,especially the presence of large raindrops within a short period of time.For the convective storms affecting Lucheng,the presence of strongest updrafts and a large amount of ice-phase graupel by riming between the 0 ℃ and-35 ℃ layers generated strong negative electric fields within the cloud.The ice-phase microphysical processes above the melting layer also played an important role in the triggering and enhancing of precipitation.

关 键 词：极端强降水 云微物理过程 双偏振雷达观测 闪电 

分 类 号：P458.2[天文地球—大气科学及气象学]