2023年4月15日临沂龙卷雷达特征和环境条件分析  

Analysis on radar characteristics and environmental conditions of the tornado in Linyi on 15 April 2023

作　　者：朱义青 万夫敬 刘新磊 谢晓华 ZHU Yiqing;WAN Fujing;LIU Xinlei;XIE Xiaohua(Key Laboratory for Meteorological Disaster Prevention and Mitigation of Shandong,Jinan 250031,China;Linyi Meteorological Service,Linyi 276004,China;Qingdao Meteorological Service,Qingdao 266003,China)

机构地区：[1]山东省气象防灾减灾重点实验室,山东济南250031 [2]临沂市气象局,山东临沂276004 [3]青岛市气象局,山东青岛266003

出　　处：《海洋气象学报》2025年第2期51-61,共11页Journal of Marine Meteorology

基　　金：中国气象局复盘总结专项(FPZJ2024-074);山东省气象局创新团队项目(SDCXTD2023-1);青岛市气象局重点课题(2023qdqxz02);山东省气象局榜单类专项项目(2023SDBD08);山东省气象局科研专项(2023SDYD30)。

摘　　要：基于常规气象观测资料、地面加密自动气象站观测资料、临沂多普勒天气雷达资料、邳州风廓线雷达资料和ERA5再分析资料,对2023年4月15日发生在山东临沂南部地区的EF2级超级单体龙卷的雷达特征和环境条件进行分析。研究发现,此次龙卷发生在弓形回波后部,龙卷母体风暴展现出经典的低层钩状回波结构,并伴有深厚的中气旋和龙卷涡旋特征(tornadic vortex signature,TVS)。中等强度的中气旋在3 km高度附近产生并发展,当其半径快速收缩且底高快速下降到1 km以下时,龙卷形成。龙卷形成前期,环境条件表现为弱的低层垂直风切变和强的大气层结不稳定。然而,随着沿冷池上升的西南低空气流与700 hPa附近的西北气流相交汇,在交汇区域形成了强的垂直风切变环境。沿冷池上升且富含不稳定能量的低空暖湿气流与对流触发区域的强垂直风切变相叠加,配合较强的上升运动,对流启动。对流启动后,丰富的不稳定能量输送促进超级单体快速增强并最终诱发龙卷。Based on conventional meteorological observing data,intensive observing data from surface automatic weather stations,Doppler weather radar data in Linyi,wind profiler radar data in Pizhou and ERA5 reanalysis data,this study analyzes the radar characteristics and environmental conditions of the EF2-rated supercell tornado that occurred in the south of Linyi,Shandong on 15 April 2023.The study finds that this tornado occurs behind a bow echo and the parent storm of the tornado exhibits a classic low-level hook echo structure,accompanied by deep mesocyclones and tornadic vortex signatures(TVS).A mesocyclone of moderate intensity forms and develops at the height of about 3 km.When its radius rapidly contracts and its base height rapidly drops below 1 km,the tornado forms.In the early stage of the tornado formation,the environmental conditions are characterized by weak low-level vertical wind shear and strong atmospheric stratification instability.However,as the southwesterly low-level jet rising along the cold pool converges with the northwesterly air current near 700 hPa,a strong vertical wind shear environment forms in the convergence area.The low-level warm and moist jet that rises along the cold pool and is rich in unstable energy,is superimposed with the strong vertical wind shear in the convection triggering area,and with the effect of strong upward motion,the convection is initiated.After the convection is initiated,the transport of abundant unstable energy promotes the rapid intensification of the supercell and ultimately induces the tornado.

关 键 词：龙卷 钩状回波 弓形回波 中气旋 

分 类 号：P445.1[天文地球—大气科学及气象学] P412.25