一次极端致灾大风的多源数据分析  

Multi-source Data Analysis of an Extreme Disaster-causing Gale

作　　者：李鸾 杨琼琼 文想成 Li Luan;Yang Qiongqiong;Wen Xiangcheng(Wuhu Meteorological Bureau,Wuhu 241000,China;East China Phased Array Weather Radar Application Joint Laboratory,Shanghai 200030,China)

机构地区：[1]芜湖市气象局,安徽芜湖241000 [2]华东区域相控阵天气雷达应用联合实验室,上海200030

出　　处：《内蒙古气象》2025年第1期19-26,共8页Meteorology Journal of Inner Mongolia

基　　金：安徽省气象局复盘总结专项项目(FPZJ202408)。

摘　　要：使用常规气象资料、X波段相控阵天气雷达以及SWAN雷达组合回波资料对2023年6月10日发生在芜湖市的一次极端致灾大风进行雷达观测和成因分析。结果表明:此次大风过程安徽省受前倾的低槽影响,芜湖市附近地面有中尺度辐合系统,同时有较强的不稳定能量,中层干冷和低层暖湿的层结不稳定结构为雷暴大风出现提供了有利的条件。相控阵雷达探测显示此次极端致灾大风影响系统为弓形回波,回波顶高最大值超过了20 km,弓形回波后有明显的后侧入流缺口,预警时间提前量为30 min;雷达剖面分析表明,对流回波前端有强上升气流,后端有下沉气流,3~9 km高度有中层径向辐合;反射率因子以及垂直积分液态水含量大值区在极端大风出现前5~10 min明显下降,可作为提前识别极端雷暴大风的预警指标;此外,相控阵雷达三维风场反演显示21:10事故发生点上空2000~4000 m处有明显的垂直风切变并逐渐增强,垂直风切变的增强使上升气流倾斜,进一步增强了中层干冷空气的卷入,加强了低层下沉气流,也是极端大风产生的原因之一,可作为临近预警指标。Radar observations and cause analysis of the extreme disaster-causing gale that occurred in Wuhu,Anhui Province,on June 10,2023,were conducted using conventional meteorological data,X-band phased array weather radar and SWAN radar combined echo data.The results showed that the gale was influenced by a forward-tilted trough in Anhui Province,with a mesoscale convergence system on the ground near Wuhu.In the meantime,the unstable atmosphere caused by strong instability energy,a layer of dry and cold air at mid-level,and a warm and moist layer at low-level provided a favorable condition for the occurrence of thunderstorm gales.Phased array radar detection revealed that this extreme disaster-causing gale was caused by a bow echo,with the maximum echo top height exceeding 20 km.A distinct rear inflow notch was observed behind the bow echo,and the detection could provide a 30-minute warning lead time.The profile features indicated that there was a strong updraft at the front of the convective echo and a downdraft at the back end,with mid-level radial convergence occurring at altitudes of 3 to 9 km.The reflectivity factor and the vertical liquid water content decreased significantly 5-10 minutes before the extreme gale happened,which could be used as early warning indicators for extreme thunderstorm gales.In addition,the three-dimensional wind inversion showed that there was obvious vertical wind shear which enhanced gradually at altitudes of 2000 to 4000 meters above the accident site at 21:10.The enhancement of vertical wind shear caused the upward airflow tilted,further enhancing the involvement of dry and cold air at mid-level,and strengthening the downdraft at low-level.This was also one of the reasons for the extreme gales and could serve as an indicator for imminent warning.

关 键 词：致灾大风 相控阵雷达 特征分析 

分 类 号：P458.123[天文地球—大气科学及气象学]