太行山地区一次人工防雹效果物理检验

Physical Evaluation of Hail Suppression Effects in the Taihang Mountain Area

选取2019年5月26日太行山东麓河北邯郸的一次人工防雹作业过程,利用石家庄SA多普勒天气雷达、邢台探空、风云卫星FY2F和ERA5再分析资料等对比分析了本次防雹作业的天气过程和作业前后各雷达探测物理量的变化。结果表明:河北邯郸在高空槽、低层切变线和高层辐散的共同影响下产生了强对流天气,防雹作业后6 min,作业云体单元最大垂直累积液态水含量(VIL)从63.4 kg m-2下降到30.0 kg m^(-2),作业后18 min,作业云体单元强回波中心高度从9.0 km下降到2.7 km,作业后42 min,最大组合反射率下降了36.5 dBZ,最大回波顶高下降了10.6 km,作业后48 min,最大VIL、强回波中心高度、最大组合反射率、最大回波顶高分别下降了97.6%、100%、57.7%、79.6%,作业云体单元各雷达探测物理量下降速率均大于发展相似但未进行防雹作业的对比云体单元。双比分析显示本次防雹作业在24 min后各物理量双比值小于1,防雹效果显著。

Based on data from the Shijiazhuang SA Doppler weather radar,Xingtai sounding station,Fengyun FY2F satellite,and ERA5 reanalysis,we investigated a hail suppression operation in Handan,Hebei Province,on May 26,2019,located in the eastern foothills of Taihang Mountain and analyzed the cloud feature variations in detail.The results showed that strong convection occurred in Handan due to the combined influence of a high-altitude trough,low-level shear lines,and high-level divergence.Particularly,6 min after cloud seeding,the maximum vertically integrated liquid water content(VIL)of the seeded cloud decreased from 63.4 to 30.0 kg m^(-2);and 18 min after seeding,the height of intense echo center of the seeded cloud decreased from 9.0 to 2.7 km;42 min after seeding,the maximum composite reflectivity decreased by 36.5 dBZ and the maximum echo top height decreased by 10.6 km;and 48 min after seeding,VIL,the height of intense echo center,maximum composite reflectivity,and maximum echo top height decreased by 97.6%,100%,57.7%,and 79.6%,respectively.The rate of decrease in each physical parameter of the seeded cloud was greater than that of a similar,unseeded cloud at a comparable development stage.The double-ratio analysis showed that 24 min after cloud seeding,the double-ratio value of each physical parameter was less than 1,indicating considerable hail suppression.