宁夏两次台风远距离暴雨过程对比分析  

Comparison of Two Long-Distance Rainstorms Caused by Typhoons in Ningxia

作　　者：苏洋 闫军 薛宏宇[1,2,3] Su Yang;Yan Jun;Xue Hongyu(Key Laboratory for Meteorological Disaster Monitoring and Early Warning and Risk Management of Characteristic Agriculture in Arid Regions,CMA,Yinchuan 750002,China;Ningxia Key Laboratory of Meteorological Disaster Prevention and Mitigation,Yinchuan 750002,China;Ningxia Meteorological Observatory,Yinchuan 750002,China)

机构地区：[1]中国气象局旱区特色农业气象灾害监测预警与风险管理重点实验室,宁夏银川750002 [2]宁夏气象防灾减灾重点实验室,宁夏银川750002 [3]宁夏气象台,宁夏银川750002

出　　处：《宁夏大学学报（自然科学版）》2023年第3期301-308,共8页Journal of Ningxia University(Natural Science Edition)

基　　金：国家自然科学基金资助项目(41965001);宁夏科技创新领军人才培养工程基金资助项目(2021GKLRLX05);宁夏自然科学基金资助项目(2022AAC03670,2023AAC03788);宁夏重点研发计划基金资助项目(2022BBF02014)

摘　　要：对宁夏两次不同类型台风远距离暴雨过程(2006-07-14,2019-08-02,以下分别简称“07·14”过程和“08·02”过程)进行对比分析,发现两次暴雨过程均发生在台风登陆减弱阶段,极值降雨量相当,强降水均出现在午后至前半夜时段;均存在内陆偏南气流与台风外围气流从“断开”到相互“联结”,导致低空急流强度显著增强的水汽通道建立的过程,其中前者低空急流强度显著强于后者;在动力条件方面,“08·02”过程中深厚的倾斜“漏斗”状河套低涡为暴雨过程提供了充足的上升运动条件,而“07·14”过程的动力抬升系统仅为近地层的冷锋和850 hPa辐合线;均存在双层假相当位温能量锋区的垂直结构特征,高层锋区向冷区倾斜而低层锋区向暖区倾斜,特别是在“08·02”过程中,河套低涡改变了热力条件,“破坏”了双层能量锋的垂直结构,在原本强度偏弱的低层能量锋上构建了新的能量锋区.A comparison of two different types of long-distance rainstorms that occurred in 14 July,2006 and 2 August,2019(referred to as 07·14 process and 08·02 process respectively hereafter)caused by typhoons in Ningxia shows that both of the two rainstorms occurred in the weakening stage of typhoon landing,with similar extreme rainfall,and strong precipitation occurred from the afternoon to the first half of the night.In both of the two processes,the inland southerly airflow and the typhoon peripheral airflow were disconnected first and then connected,resulting in the establishment of water vapor channel with significantly enhanced low-level jet intensity,and the low-level jet intensity in the former was significantly stronger than that in the latter.In terms of dynamical analysis,the deep inclined funnel shaped Hetao low vortex in the 08·02 process provided sufficient ascending motion conditions for the rainstorm process,however,the dynamic lifting system of the 07·14 process was only the cold front near the formation and the convergence line at 850 hPa.Both processes had the vertical structure characteristics of the double-layer pseudo equivalent potential temperature energy frontal zone,the upper frontal zone tilted towards the cold and the lower frontal zone tilted towards the warm.In particular,the Hetao low vortex changed the thermal conditions during the 08·02 process,and itdestroyed the two-layer energy frontal zone vertical structure,thus a new energy frontal zone was constructed on the originally lower energy frontal zone with weak intensity.

关 键 词：台风 远距离暴雨 统计特征 对比分析 

分 类 号：P458.121.1[天文地球—大气科学及气象学]