一次强降水超级单体风暴双偏振参量特征分析  

Polarimetric Signatures of a Supercell Thunderstorm Occourred in Gaomi on 3 August 2020

作　　者：黄秀韶 李芳[3] 刁秀广[1,4] HUANG Xiushao;LI Fang;DIAO Xiuguang(Key Laboratory for Meteorological Disaster Prevention and Mitigation of Shandong,Jinan 25o03l;Shandong Institute of,Meteorological Sciences,Jinan 250031;Jining Meteorological Bureau,Shandong,Jining 272000;Shandong Meteorological Observatory,Jinan 250031)

机构地区：[1]山东省气象防灾减灾重点实验室,济南250031 [2]山东省气象科学研究所,济南250031 [3]山东省济宁市气象局,济宁272000 [4]山东省气象台,济南250031

出　　处：《气象科技》2022年第6期830-841,共12页Meteorological Science and Technology

基　　金：山东省自然科学基金项目(ZR2020MD053、ZR2022MD088);山东省气象局科研项目(2019sdqxz01)共同资助。

摘　　要：利用青岛双偏振多普勒天气雷达资料和探空及自动气象站观测资料,对2020年8月3日发生在山东高密的一次强降水超级单体风暴双偏振特征进行了分析。结果表明:(1)强的对流有效位能(CAPE)、低层强垂直风切变、高空强辐散及高湿是强降水风暴发展维持的关键环境因素。(2)风暴低层存在差分反射率因子Z_(DR)弧和差分相移率KDP高值区,Z_(DR)弧与入流缺口一侧反射率因子梯度高值区相匹配,对应偏小的KDP和相关系数,以少量大粒子为主;KDP高值区为强降雨区,对应小于3 dB的Z_(DR)和大的相关系数,以高浓度、大小适中的液态粒子为主。(3)有界弱回波区BWER外围存在Z_(DR)环,对应偏小的KDP,而BWER上方存在深厚宽阔的Z_(DR)柱和KDP柱,KDP柱高于Z_(DR)柱的高度,气旋性旋转上升气流区内中层以下分布有少量大的粒子,而中层之上分布有较高浓度的大粒子。(4)-20℃层高度之下含有丰富的液态粒子,-20℃层高度之上含有丰富的霰粒子和冰晶粒子,是高密强降水超级单体风暴典型的微物理垂直结构特征。Using Qingdao dual-polarization CINRAD/SA data,sounding and automatic meteorological station data,the polarimetric signatures of a supercell storm occurred in Gaomi,Shandong Province on 3 August 2020 are analyzed.The results show that:(1)The key environmental factors to the development and maintenance of the Gaomi supercell were the strong CAPE,strong low-level vertical wind shear,200 hPa strong divergence and high humidity.(2)The Z_(DR)arcs and KDPhigh-value areas were important characteristics of the lower layer.The Z_(DR)arcs matched the high-value region of reflectivity factor gradient on one side of the inflow and correspond to smaller KDP,which were caused by a few large particles.The KDPhigh-value area in the middle of the storm,corresponding to the smaller Z_(DR)(1-3 dB),larger CC,caused by the high concentration of smaller particles,was the heavy rainfall area.(3)The Z_(DR)ring around BWER,corresponding to smaller KDP,indicate that a small number of large droplets were distributed around BWER.The deep and wide Z_(DR)and KDPcolumns above the BWER indicate that the higher concentration of large droplets was distributed above the BWER.(4)Abundant liquid particles under the-20℃layer and abundant graupel and ice crystal particles above the-20℃layer were the typical vertical characteristics of the microphysics of the Gaomi supercell.

关 键 词：强降水超级单体 双偏振 Z_(DR)柱 KDP柱 

分 类 号：P412.2[天文地球—大气科学及气象学]