“4·29”山东近海10级以上雷暴大风的成因分析  

Cause of a Thunderstorm Gale Event over Grade 10 Along the Shandong Coast on 29 April 2021

作　　者：侯淑梅 李昱薇[2] 张鹏 朱晓清 高荣珍 张永婧 梅婵娟[6] 石磊 朱义青 HOU Shumei;LI Yuwei;ZHANG Peng;ZHU Xiaoqing;GAO Rongzhen;ZHANG Yongjing;MEI Chanjuan;SHI Lei;ZHU Yiqing(Key Laboratory for Meteorological Disaster Prevention and Mitigation of Shandong,Jinan 250031;Shandong Meteorological Observatory,Jinan 250031;Liaocheng Meteorological Office of Shandong Province,Liaocheng 252000;Qingdao Meteorological Office of Shandong Province,Qingdao 266003;Jinan Meteorological Office of Shandong Province,Jinan 250102;Weihai Meteorological Office of Shandong Province,Weihai 264200;Yantai Meteorological Office of Shandong Province,Yantai 264001;Linyi Meteorological Office of Shandong Province,Linyi 276004)

机构地区：[1]山东省气象防灾减灾重点实验室,济南250031 [2]山东省气象台,济南250031 [3]山东省聊城市气象局,聊城252000 [4]山东省青岛市气象局,青岛266003 [5]山东省济南市气象局,济南250102 [6]山东省威海市气象局,威海264200 [7]山东省烟台市气象局,烟台264001 [8]山东省临沂市气象局,临沂276004

出　　处：《气象》2022年第10期1242-1256,共15页Meteorological Monthly

基　　金：山东省自然科学基金项目(ZR2021MD010);山东省气象局精准预报技术创新团队(SDCXTD2021-1);中国气象局预报员专项(CMAYBY2018-041);山东省气象局重点课题(2016sdqxz01)共同资助。

摘　　要：2021年4月29日山东近海出现10~13级雷暴大风,造成一艘渔船翻扣。基于多普勒天气雷达、地面加密自动气象观测站、ERA5再分析及常规观测资料,分析了此次雷暴大风的成因,结果表明:东北冷涡后部强盛的西北气流携带干冷空气叠加在低层暖温度脊之上,强烈的位势不稳定层结和垂直风切变为当天产生强对流天气提供了有利的环境条件。高空强劲的西北气流,一方面导致阵风锋移动速度快,另一方面高空动量下传,增大了下沉气流的角动量。阵风锋移动速度快、持续时间长,是造成所经之地产生10级以上雷暴大风的直接原因。对流层中低层大气干燥,高层水凝物下落过程中蒸发降温,在近地面形成厚度高达120 hPa的冷池。小尺度冷池造成的加压与大尺度气旋后部增压叠加,与气旋的减压区形成变压风。冷池与日照暖温度脊之间产生的密度流与变压风叠加,造成地面大风强度增强。冷池小高压入海后气压梯度方向转变造成风向发生旋转,增加了渔船翻扣的风险。日照上空的蒸发作用、锋区梯度、密度流强度、多尺度天气系统的叠加效应均比青岛强,导致处于青岛雷暴边缘的日照市出现10级以上雷暴大风的强度和范围均比受青岛雷暴主体影响的青岛市大。The thunderstorm gale as powerful as grade(10-13)overturned a fishing ship along the Shandong Coast on 29 April 2021.The causes of this thunderstorm gale process are investigated in this paper based on the data of Doppler weather radar and densely-distributed automatic weather station,ERA5 reana-lysis data and the conventional observation data.The results show that the cold and dry air coming from northwest behind the northeast China cold vortex superimposed the lower-level warm ridge,and the strong potential instability stratification and vertical wind shear provided favorable environmental conditions for this severe convection weather.Under the influence of the strong upper-level northwest steering currents,the advection of both the Qingdao thunderstorm and the gust front were fast,and the angular momentum of downdraft was increased due to momentum downward-transporting.The gust front lasted for a long time and moved fast,directly causing thunderstorm gale of grade 10-13 to hit the places it passed through.Dry air in the middle-low troposphere and evaporative cooling of upper-level hydrometeor during its falling process,formed a cold pool with thickness up to 120 hPa near the ground.Allobaric wind formed between the pressurization area at the rear of the large-scale cyclone superimposed with the small-scale cold pool and the decompression area of the cyclone.Density currents between the cold pool and warm ridge in Rizhao superimposed with allobaric wind led to enhancement of surface wind.Considering the orientation of the pressure gradient changed after the high pressure cold-core entering sea.Wind direction became rotated so that the risk of fishing boat overturning increased.The evaporation,gradient of the frontal zone,intensity of density flow and superposition effect of the multi-scale weather system over Rizhao,were all stronger than those in Qingdao,so that the thunderstorm gales above grade 10 in Rizhao City,which lay on the edge of Qingdao thunderstorm,had a greater power and scope than those in Qingdao

关 键 词：阵风锋 密度流 多尺度天气系统叠加 蒸发降温 高空动量下传 变压风 

分 类 号：P458[天文地球—大气科学及气象学]