雅安市一次暖区强降水过程中多普勒雷达回波特征分析  

Analysis of Doppler radar echo characteristics in a warm-sector heavy rainfall process in Ya’an

作　　者：闵涛[1] 吴筱 高文良[1] 周学云[1] 吴亚平[1] MIN Tao;WU Xiao;GAO Wenliang;ZHOU Xueyun;WU Yaping(Meteorological Bureau of Ya’an in Sichuan Province,Ya’an 625000,China;Meteorological Bureau of Jiuzhaigou in Sichuan Province,Jiuzhaigou 623400,China)

机构地区：[1]四川省雅安市气象局,四川雅安625000 [2]四川省九寨沟县气象局,四川九寨沟623400

出　　处：《中低纬山地气象》2020年第3期13-18,共6页Mid-low Latitude Mountain Meteorology

基　　金：雅安市气象局课题(2018-01);雅安市暖区暴雨概念模型;雅安市气象局课题(2016-01);雅安市灾害性天气预报创新团队。

摘　　要：针对2018年7月14日雅安市发生的一次暖区强降水过程,该文利用多普勒天气雷达、常规观测和加密自动站观测资料,对此次过程发生的环境条件和雷达回波的发展传播机制进行分析。结果表明:①回波的发展及维持主要是由于上游对流系统的移入以及对流系统内部的再触发机制;②当回波走向与环境平均风较一致时,可判断未来回波将沿环境平均风方向发展传播。③通过分析地面气象要素气压和气温的变化可判断冷池是否形成,气压陡升和气温骤降表明地面冷池已经形成,而两者变化趋势重叠的时间段表明冷池持续出现。此时若雷达低层风场显示不断有暖湿气流输送过来,有利于对流系统内部不断触发新的对流单体,这种对流系统内部的再触发机制有利于强回波的长时间维持。Based on Doppler weather radar data,conventional observation data and automatic station data,a warm-sector heavy rainfall process in Ya'an city on July 14,2018 was analyzed from the environmental conditions and the developing communication mechanisms of radar echoes.The results indicate that:①The initial echoes the development and maintenance of the echoes are mainly due to the influx of upstream convective system and the re-triggering mechanism in convective system;②When the trend of echo is consistent with the mean wind,it can be judged that the echo will develop and spread along the mean wind in the future.③The formation of cold pool can be judged by analyzing the changes of air pressure and temperature of surface meteorological elements.The sudden rise of air pressure and drop of air temperature indicate that the cold pool has been formed,and the time period when the two trends overlap indicates that the cold pool continues to appear.At this time,if the warm and wet air flow is continuously conveyed in the low-level wind field of radar,it is beneficial to trigger new convective units in the convective system,and the re-triggering mechanism in the convective system is conducive to the long-term maintenance of strong echoes.

关 键 词：对流系统 再触发机制 冷池 暖湿气流 

分 类 号：P426.6[天文地球—大气科学及气象学] TN958.95[电子电信—信号与信息处理]