2017年苏南一次特大暴雨高分辨率模拟及特征分析  

Characteristics and simulation of a torrential rainstorm over southern Jiangsu in 2017 revealed by a high-resolution numerical model

作　　者：张冰 郑媛媛[1,2,3,4] 沈菲菲[5] 曾明剑 王元直[5] ZHANG Bing;ZHENG Yuanyuan;SHEN Feifei;ZENG Mingjian;WANG Yuanzhi(Key Laboratory of Transportation Meteorology,China Meteorological Administration(LATM-CMA),Nanjing 210009,China;Nanjing Joint Center of Atmospheric Research(NJCAR),Nanjing 210009,China;Nanjing Joint Institute for Atmospheric Sciences,Nanjing 210009,China;Jiangsu Institute of Meteorological Sciences,Nanjing 210009,China;Key Laboratory of Meteorological Disaster,Ministry of Education/Joint International Research Laboratory of Climate and Environment Change/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters,Nanjing University of Information Science&Technology,Nanjing 210044,China)

机构地区：[1]中国气象局交通气象重点开放实验室,南京210009 [2]南京大气科学联合研究中心,南京210009 [3]南京气象科技创新研究院,南京210009 [4]江苏省气象科学研究所,南京210009 [5]南京信息工程大学气象灾害教育部重点实验室/气候与环境变化国际合作联合实验室/气象灾害预报预警与评估协同创新中心,南京210044

出　　处：《气象科学》2021年第3期386-397,共12页Journal of the Meteorological Sciences

基　　金：国家自然科学基金资助项目(G41805016,G41805070);江苏省“333工程”科研项目资助计划项目(BRA2014374,BRA2018100);江苏省自然科学基金资助项目(BK20170940,BK20160954);气象灾害教育部重点实验室(南京信息工程大学)开放课题(KLME201807,KLME201808);高原与盆地暴雨旱涝灾害四川省重点实验室开放研究基金项目(SZKT201901);中国气象局沈阳大气环境研究所和东北冷涡研究重点开放实验室联合开放基金项目(2020SYIAE07);北极阁开放研究基金—南京大气科学联合研究中心项目(NJCAR2018ZD03)。

摘　　要：利用高分辨率(水平3 km)数值模式,结合FNL分析及预报场资料、地面加密自动站观测资料和多普勒雷达资料,对2017年6月9—10日苏南一次因江淮气旋沿切变线东移造成的特大暴雨过程进行研究。首先对模式模拟结果做了降水、风场等多方面的验证,随后利用模拟结果和观测资料对该特大暴雨过程的对流系统结构及其发展维持机制进行分析。结果表明:(1)高分辨率模式能较客观地反映该暴雨过程诸多大气参数的演变。(2)特大暴雨过程中锋面气旋东移且倾斜发展,深对流中心维持在气旋的东南方向,该中尺度对流系统的发生发展与锋面气旋的上述演变密切相关。(3)特大暴雨过程中相应的对流处于旺盛阶段时,大气不稳定能量持续释放,中层为相对较高的假相当位温区,即明显的暖心结构,垂直上升运动最强,且其南北两侧均有下沉气流,形成中尺度次级环流,维持强对流不断发展。(4)超低空急流的持续增强,沿低层切变线上不断有γ中尺度涡旋生成和足够的低层辐合区厚度是导致这次特大暴雨过程的关键因素。By using the high-resolution(3 km horizontally)numerical model,combined with FNL analysis and forecast data,automatic weather station data,and Doppler radar data,the torrential rainstorm caused by a Jianghuai cyclone moving eastward along the shear line in southern Jiangsu from 9 to 10 June 2017 was studied.Firstly,the numerical results were verified for various fields including the precipitation and wind,and then the structure of convective system of the torrential rainstorm process and its mechanism of development and maintenance were analyzed with the numerical simulation results as well as observation data.Results indicate that(1)the high-resolution model is able to describe the evolution of many atmospheric parameters during the rainstorm objectively.(2)The frontal cyclone moves eastward and inclines during the torrential rainstorm,and the deep convective center maintains in the southeastern direction of the cyclone.Therefore,the occurrence and development of mesoscale convective system are closely related to the above evolution of the frontal cyclone.(3)When the convection related to the torrential rainstorm is at its vigorous stage,the atmospheric unstable energy is continuously released,while the middle layer is a relatively high pseudo-equivalent potential temperature zone,that is,an obvious warm core structure,where the vertical upward motion is the strongest and downdraft exists on both the north and south sides,forming mesoscale secondary circulations and maintaining the continuous development of the strong convection.(4)The continuous strengthening of the ultra-low level jet,the generation ofγmesoscale vortices along the sides of low sheers together with sufficient depths of the low convergence are the key factors for the existence of the torrential rainstorm event.

关 键 词：特大暴雨 数值模拟 γ中尺度涡旋 超低空急流 

分 类 号：P458.3[天文地球—大气科学及气象学]