青海一次短时强降水中FY-4A云型特征分析  

Analysis of FY-4A Cloud Pattern Characteristics in A Short-term Heavy Rainfall in Qinghai Province

作　　者：谢天蓉 祁彩虹 张宁瑾 Xie Tian-rong(Qinghai Provincial Meteorological Bureau,Xining,Qinghai 810000)

机构地区：[1]青海省气象局,青海西宁810000

出　　处：《农业灾害研究》2023年第10期235-237,共3页Journal of Agricultural Catastrophology

摘　　要：利用逐时雨量资料、常规高空气象观测资料及FY-4A卫星云图资料,对青海省2019年6月30日短时强降水天气过程的天气形势配置和卫星云图演变特征进行统计分析。结果表明:此次短时强降水天气过程发生在500 hPa高原切变线附近,定义为高原低涡切变线型,带来短时强降水的云型特征为多个对流云团排列而成的东北—西南走向带状云团,与高原切变线位置重合,随着高原切变线的发展移动而发生变化;组成带状云团的对流云团外形有的近似圆形,有的近似椭圆,面积相差较大,在1~4个平方纬距;云系后部为下沉的西北气流对应的无云区,前部为槽前西南气流,带状云团前侧为强正涡度平流区,对应强的上升运动,云系稠密;云顶亮温较低,持续时间较短,但由于其列车效应明显,不断有新的对流云团生成发展,最终形成具有东北—西南走向长轴的椭圆云团,面积最大可达12个平方纬距。This article uses hourly rainfall data,conventional high-altitude meteorological observation data,and FY-4A satellite cloud image data to statistically analyze the weather situation configuration and satellite cloud image evolution characteristics of the short-term heavy rainfall weather process in Qinghai Province on June 30,2019.The results show that the short-term heavy precipitation weather process occurred near the 500 hPa plateau shear line,defined as the plateau low vortex shear line,and the cloud type characteristic that brought short-term heavy precipitation was a northeast southwest trending banded cloud cluster formed by multiple convective cloud clusters,which coincides with the position of the plateau shear line and changes with the development and movement of the plateau shear line;The convective cloud clusters that make up the banded cloud clusters have shapes that were approximately circular or elliptical,with significant differences in area,ranging from 1 to 4 square latitudes;The rear part of the cloud system was a cloudless area corresponding to the sinking northwest airflow,the front part was the southwest airflow in front of the trough,and the front side of the banded cloud cluster was a strong positive vorticity advection area,corresponding to strong upward motion,resulting in a dense cloud system;The brightness temperature at the top of the cloud was relatively low and the duration was short.However,due to its obvious train effect,new convective cloud clusters were constantly generated and developed,ultimately forming elliptical cloud clusters with a northeast southwest long axis,with a maximum area of up to 12 square latitudes.

关 键 词：短时强降水 高原低涡切变型 云型特征 带状云团 

分 类 号：P458.121.1[天文地球—大气科学及气象学]