摘要
2022年6月21日傍晚,青海省黄南藏族自治州出现一次暴雨天气过程,局地强降水出现在泽曲镇夸日龙村,6小时累计降水量达51 mm,最大小时雨强达34.2 mm。文章利用常规观测资料、ERA5再分析资料、风云卫星资料及黄南C波段双偏振多普勒天气雷达资料等,对此次高原汛期局地暴雨天气成因进行分析。结果表明:(1)此次过程是西南暖湿气流背景下的地面中尺度辐合线触发的局地暴雨天气。(2)FY-4A显示降水发生时受厚冰云覆盖,云顶气压明显下降,云顶高度较高。(3)从雷达回波来看,泽曲镇地区回波强度达到60 dBZ左右,云顶高度达12 km,垂直液态水含量达到17 kg/m^(2),表明对流云不仅发展旺盛,且水汽含量大。从偏振参量来看,大的Zc对应大的ZDR及KDP,表明对流单体中含有大量大雨滴,大量大雨滴短时间内降落极易产生短时强降水。双偏振定量降水估计产品OHP(169)对于降水落区及量级预估均比单偏振产品更准。分析结果可为类似的极端强降水精细化预报预警提供参考依据。
On the evening of June 21,2022,a rainstorm occurred in Huangnan,Qinghai.The local heavy precipitation occurred in Kwarilong Village,Zequ Town.The accumulated precipitation in 6 hours reached 51mm,and the strongest hourly rain intensity reached 34.2 mm.In this paper,using conventional observation data,ERA5 reanalysis data,Fengyun satellite data and C-band dual-polarization Doppler weather radar data of Huangnan,the causes of the local rainstorm in the first flood season of the plateau are analyzed.The results show that:(1)This process was a local rainstorm triggered by the ground mesoscale convergence line under the background of southwest warm and humid airflow.(2)FY4A shows that when precipitation occurred,it is covered by thick ice clouds,the cloud top pressure drops obviously,and the cloud top height is higher.(3)From the radar echo,the echo intensity of Zequ Town is about 60dBZ,the cloud top height is 12km,and the vertical liquid water content is 17kg/m^(2),which indicates that the convective cloud not only develops vigorously,but also has a large water vapor content.From the polarization parameters,large Zc corresponds to large ZDR and KDP,which indicates that convection cells contain a large number of large raindrops,and a large number of large raindrops falling in a short time is easy to produce short-term heavy precipitation.The dual polarization quantitative precipitation estimation product OHP(169)is more accurate than the single polarization product in predicting the precipitation area and magnitude.
作者
宋仙芳
王敏
陈晶
郭安欣
任强
Song Xianfang;Wang Min;Chen Jing;Guo Anxin;Ren Qiang(Huangnan Prefecture Meteorological Observatory of Qinghai Province,Tongren 811399,China)
出处
《青海科技》
2023年第2期119-126,共8页
Qinghai Science and Technology
关键词
短时暴雨
黄南地区
双偏振雷达
中尺度
Short term rainstorm
Huangnan area
Dual-polarimetric radar
Mesoscale
