滇西北一次降雹过程的多普勒天气雷达回波特征分析  

Analysis of Doppler radar echo characteristics of a hail process on plateau of northwest Yunnan

作　　者：张崇莉 赖云华 杨有仁 濮蝶天 

机构地区：[1]云南省丽江市气象局,丽江674100

出　　处：《暴雨灾害》2012年第1期72-77,共6页Torrential Rain and Disasters

基　　金：云南省气象局预报员专项"VWP产品在短时临近预报中的应用研究"(YB201213)

摘　　要：利用丽江新一代天气雷达回波资料,结合Micaps常规观测资料,对2011年6月14日下午出现在滇西北高原丽江市一区三县的区域性冰雹过程进行分析。结果表明:区域性冰雹过程发生在青海附近"Ω"环流及前部有切变东移、丽江高层为西北气流控制、低层受辐合区影响、地面配合回流冷空气及丽江东部独特地形影响等环境条件下;冰雹云回波在基本反射率因子图上呈点状、线状排列,发展到强盛时出现钩状回波,在VCS(Vertical Cross Section)图上强回波核高度为6～10 km,并出现回波墙结构特征;冰雹云发展阶段在基本径向速度图上可见逆风区和中尺度辐合;垂直累积液态水含量(Vertically Integrated Liquid Water Content,VIL)在降雹前均有不同程度跃增,跃增达到阈值35 kg.m-2后,地面降雹;高空偏北气流是丽江出现冰雹时垂直风廓线产品图(VAD Wind Profile,VWP)中的主要特征,偏北气流越强,持续时间越长,受其影响出现区域性冰雹的可能性越大。Doppler radar echo data of Lijiang and Micaps conventional observation data were used to analyze a regional hail process occurred in the afternoon on 14 June 2011 in Lijiang city of northwest Yunnan.The main results are as follows： this hail process occurred in the weather situation that the upper atmosphere was controlled by northwest flow and lower atmosphere was influenced by convergence zone with accompanying of backflow of cool air on the surface as well as the unique topography condition.In the basic reflectivity factor figure,hail cloud echo shows the linear arrangement and patch,and hooked echo appears when development of hail cloud is too strong.On the VCS（vertical cross section） vertical profiles chart,the strong echo nucleus reaches 6-10 km highly,and presents the echo wall characteristics.On the basic radial velocity image the adverse wind area and mesoscale convergence zone can be seen in hail cloud development stage,VIL（vertically integrated liquid water content） values will be increased continuously in a leap in varying degrees before the hail occurring,and when the valures reach 35 kg.m-2 hail will begin.The upper air presenting northerly air current on the VWP（VAD wind profile） chart is chief feature when the hail appeared in Lijiang.

关 键 词：冰雹 雷达回波 冷空气 滇西北 

分 类 号：P458.121.2[天文地球—大气科学及气象学]