合肥一次低空风切变的观测与分析  

The observation and discussion on mechanism about a typical low-level wind shear in Hefei

作　　者：赵倩 周后福 单乃超 ZHAO Qian;ZHOU Houfu;SHAN Naichao(Anhui Institute of Meteorological Sciences,Hefei 230031,China;Anhui Key Labrotory of Atmospheric Science and Satellite Remote Sensing,Hefei 230031,China;Meteorological Observation Centre,China Meteorological Administration,Beijing 100081,China;Shouxian National Climatology Observatory,Anhui Shouxian 232200,China;Huaihe River Basin Typical Farm and Ecological Field Science Experiment Base of China Meteorological Administration,Anhui Huainan 233300,China;Meteorological Station,Anhui Air Traffic Control Sub-Bureau,Hefei 230051,China)

机构地区：[1]安徽省气象科学研究所,合肥210031 [2]安徽省大气科学与卫星遥感重点实验室,合肥210031 [3]中国气象局气象探测中心,北京100081 [4]寿县国家气候观象台,安徽寿县233300 [5]中国气象局淮河流域典型农田生态气象野外科学试验基地,安徽淮南233300 [6]民航安徽空管分局气象台,合肥230051

出　　处：《气象科学》2019年第5期704-710,共7页Journal of the Meteorological Sciences

基　　金：国家自然科学基金资助项目(U1533131);安徽省气象科技发展基金项目(KM201608);国家重点研发计划项目(2018YFC1507502);华东气象协同创新基金(QYHZ201816);安徽省公益性研究联动计划项目(1604f0804002)

摘　　要：本文基于合肥地面观测、机场自动观测系统(AWOS)、多普勒雷达、探空及FNL 0.25°×0.25°等资料,分析了2015年8月6日合肥一次较强风切变天气过程,并对其形成机理进行研究。结果表明:低空风切变发生前,肥西地区不稳定能量及上升气流较为活跃,有利于对流云团的发展。地面自动气象站的观测资料表明,低空风切变发生时,近地层的风向、风速和温度等气象要素均有突变;风暴的质心高度、最强回波高度和风暴顶高迅速下降,空中气流快速下沉,至近地面向四周辐散,因此该风暴属于下击暴流性质;径向速度图中明显的正负速度对也印证了低空剧烈的风向和风速切变。The paper has validated and discussed the mechanism about a strong low-level wind shear appeared on August 6,2015 in Hefei based on Hefei ground observation data,Automatic Weather Observing System(AWOS)of airport,Doppler radar data,sounding balloon and 0.25°×0.25°FNL data.Main conclusions are as following.The unstable energy and upward flow were rather strong which is beneficial to the development of the convection in Feixi county before low-level wind shear happening.The ground observation data measured that wind speed,wind direction as well as temperature changed rapidly near the ground when low-level wind shear occurs.At the same time,the quick dropping of the height of center of mass,the height of the strongest echo and the top height about the storm indicated that the air flows declined fast and diverged to all around as soon as they reached the ground.So this storm belonged to the characteristic about downburst.What s more,positive-negative velocity verified the strong wind speed and direction shear near the ground.

关 键 词：低空风切变 多普勒雷达 径向速度 下击暴流 质心高度 

分 类 号：P412.25[天文地球—大气科学及气象学]