2020年绥化地区一次超级单体龙卷及其环境特征分析  

Characteristics and physical condition analyses of a supercell tornado in the Suihua area in 2020

作　　者：吴迎旭[1] 周一[1] 赵柠[1] 栾晨[1] 张礼宝[1] 赵美玲 蔡康龙 赵广娜 WU Ying-xu;ZHOU Yi;ZHAO Ning;LUAN Chen;ZHANG Li-bao;ZHAO Mei-ling;CAI Kang-long;ZHAO Guang-na(Heilongjiang Meteorological Observatory,Ha′erbin 150030,China;Foshan Meteorological Service Foshan 528000,China;Haerbin Meteorological Service,Ha′erbin 150028,China)

机构地区：[1]黑龙江省气象台,黑龙江哈尔滨150030 [2]佛山市气象局,广东佛山528000 [3]哈尔市气象局,黑龙江哈尔滨150028

出　　处：《气象与环境学报》2023年第3期10-19,共10页Journal of Meteorology and Environment

基　　金：国家重点基础研究发展规划(2018YFC1507301、2018YFC1507305);黑龙江省自然科学基金(LH2020D014)共同资助。

摘　　要：利用常规资料、区域自动站资料、FY-4卫星云图、新一代天气雷达、ECMWF再分析资料,分析2020年8月9日黑龙江省绥化市绥胜满族镇EF2级龙卷的结构特征、形成过程和触发机制。结果表明:此次龙卷发生在东北冷涡底前部500 hPa为西南气流、低层为暖式切变线、地面为暖锋的背景下;中层干输送有利于下沉气流,低层暖湿气流和高空辐散加强了气流的上升,增强的水平涡度在较强的低层垂直风切变作用下形成涡管,提供了有利龙卷发生的环境条件。较小的低层温度递减率、较大的对流抑制能量、地面两条辐合线共同触发形成超级单体。不同于黑龙江省历次龙卷过程,此次龙卷天气的对流有效位能较低、对流抑制能量较大,没有干线触发。中等强度深厚的中气旋由0.5°仰角向上发展至中层并加强,维持时间约50 min,当中气旋在中层旋转速度超过低层时,龙卷产生。Using the conventional data,regional automatic station data,FY-4 satellite cloud image,a new generation weather radar,and the ECMWF reanalysis data,the structural characteristics,formation process,and trigger mechanism of EF2 tornado in Suisheng Manchu town of Suihua city in Heilongjiang province on August 9,2020,were analyzed.The results show that the tornado occurs under the background of the southwest airflow at 500 hPa in the front of the northeast cold vortex bottom,the warm shear line in the lower level,and the warm front on the ground.The dry transport in the middle layer is conducive to the sinking airflow,the warm and wet airflow in the lower layer and the divergence in the upper layer strengthen the rise of the airflow,and the enhanced horizontal vorticity forms a vortex tube under the action of strong vertical wind shear in the lower layer,providing favorable environmental conditions for the occurrence of tornadoes.The smaller the temperature lapse rate in the lower layer,the larger the convection suppression energy and the two convergence lines on the ground trigger the formation of supercells together.Different from previous tornado processes in Heilongjiang province,the convective effective potential energy of this tornado weather is low,the convective suppression energy is large,and there is no mainline trigger.The medium intensity and deep mesocyclone develops from 0.5°elevation to the middle level and strengthens,and the maintenance time is about 50 minutes.When the rotation speed of the mesocyclone in the middle level exceeded that of the low level,the tornado is generated.

关 键 词：龙卷 超级单体 环境条件 触发机制 

分 类 号：P458[天文地球—大气科学及气象学]