江苏阜宁EF4级龙卷的高分辨率数值模拟研究  

High Resolution Numerical Simulation of an EF4 Tornado in Funing,Jiangsu Province

作　　者：朱皓清 赵宇[1] ZHU Haoqing;ZHAO Yu(Key Laboratory of Meteorological Disaster(KLMD),Ministry of Education and Jiangsu Province,Nanjing University of Information Science&Technology,Nanjing 210044,Jiangsu,China;Qidong meteorological Bureau,Jiangsu Province,Qidong 226200,Jiangsu,China)

机构地区：[1]南京信息工程大学气象灾害教育部重点实验室/气象灾害预报预警与评估协同创新中心/气候与环境变化国际合作联合实验室,江苏南京210044 [2]江苏省启东市气象局,江苏启东226200

出　　处：《高原气象》2022年第6期1599-1614,共16页Plateau Meteorology

基　　金：国家重点研发计划项目(2018YFC1506102);国家自然科学基金项目(41975055)。

摘　　要：利用美国Advanced Regional Prediction System(ARPS)模式,采用水平分辨率分别为9 km、1 km、250 m和75 m的四重单向嵌套网格,模拟了2016年6月23日发生在江苏阜宁的EF4级龙卷过程。结果表明:1 km、250 m和75 m网格都可以复制出龙卷风暴的一般特征,包括钩状回波和旋转上升运动等;250 m网格可以模拟出类龙卷涡旋(Tornado-like Vortex,TLV),75 m网格才可以解析出龙卷涡旋。TLV和龙卷涡旋的形成和增强是近地面上升运动增强导致的,随着模式分辨率的提高,模拟的近地面上升运动更强,模拟的TLV强度更强,持续时间更长。250 m和75 m网格模拟的龙卷的最强级别分别为EF2级和EF3级。龙卷涡旋最初是由若干个强度较强的小尺度涡旋合并形成的,次级出流阵风锋的辐合作用进一步增强了龙卷涡旋,从而发展至成熟阶段。成熟的龙卷涡旋呈现从单涡旋到双涡旋最后到多涡旋龙卷的演变。An EF4 supercell tornado hit Funing,Jiangsu Province,China on 23 June 2016,causing serious disaster. The tornado process was simulated with the Advanced Regional Prediction System(ARPS)model using four one-way nested grids of horizontal grid spacing of 9 km,1 km,250 m and 75 m. The results show that the model reproduced the general characteristics of the observed tornadic supercell,including hook echo and rotational ascending motion on 1 km,250 m and 75 m grids. Tornado-like vortex(TLV)was produced on 250 m grid,and tornado-like vortex can be reproduced only on 75 m grid. The formation and intensification of TLVs and tornado vortex are caused by the intensification of near-surface ascending motion. Associated with the improvement of model resolution,the simulated near-surface ascending motion become stronger,and reproduced stronger and last longer TLV. The strongest levels of tornado reproduced on 250 m and 75 m grid is EF2 and EF3,respectively. The tornado vortex is initially generated by the combination of a series of strong small-scale vortices,the convergence caused by secondary outflow gust front strengthens the intensity of tornado vortex further to mature stage,and the convergence of the secondary outflow front further enhanced the tornado vortex to the mature stage. The mature tornado vortex experienced the evolution from one-cell to two-cell and finally to multi-vortex tornado.

关 键 词：龙卷风暴 多涡旋龙卷 模拟 高分辨率 ARPS模式 

分 类 号：P445.2[天文地球—大气科学及气象学]