一次弱垂直风切变环境条件下短时大暴雨的研究  

Analysis of a Short-time Heavy Rain in Weak Vertical Wind Shear Environment

作　　者：罗王军 蒋友严[2] 霍佳宇 敖泽建 LUO Wangjun;JIANG Youyan;HUO Jiayu;AO Zejian(Gannan Tibetan Autonomous Prefecture Meteorological Bureau,Gannan 747000,China;Northwest Regional Climate Center,Lanzhou 730020,China;Shanxi Meteorological Disaster Prevention Technology Center,Taiyuan 030002,China)

机构地区：[1]甘南州气象局,甘肃甘南747000 [2]西北区域气候中心,甘肃兰州730020 [3]山西省气象灾害防御技术中心,山西太原030002

出　　处：《沙漠与绿洲气象》2019年第2期32-39,共8页Desert and Oasis Meteorology

基　　金：甘肃省自然科学基金青年基金项目"21世纪初祁连山积雪变化对周边生态环境影响"(1506RJYA189);中国气象局气候变化专项"典型生态环境下的气候容量研究"(CCSF201612)资助

摘　　要：利用雷达回波、探空、区域自动站降水资料,对2016年8月22日发生在甘肃省甘南州碌曲县的局地大暴雨天气过程进行分析。结果表明:这是一次在弱垂直风切变环境条件下发生在两个592 dagpm副热带高压之间切变区的短时大暴雨,地面冷锋、露点锋以及地形抬升共同触发了对流;前期的逆温层结和高温高湿状态的空气对大暴雨发生有很重要的指示意义;大暴雨发生时有强烈的上升运动和明显的的水汽输送;新单体与旧单体的合并指示强降水的开始,降水主要集中在回波开始合并增强到趋于减弱的近2 h内,垂直积分液态水含量大于1.00 kg/m^2的时段每10min降水量基本在10 mm以上。Based on the radar echo,sounding and regional automatic meteorological station precipitation data,a local heavy rainfall which occurred in weak vertical wind shear condition in Luqu County, Gannan Tibetan Autonomous Prefecture,Gansu Province on August 22,2016 was analyzed.The results show that it was a short-time heavy precipitation occurred between two 592 dagpm high pressures.The breakage of the 592 dagpm high pressure which make Luqu involved in the shear zone.The ground cold front,the dew point front and the surface topography jointly trigger the convection.The inversion stratosphere and the wet and warm air play indicative roles for the occurrence of heavy precipitation, which is accompanied by the strong updraft and obvious water vapor transportation. The combination of the developing storm and mature storms implies the beginning of the rainfall process,and the precipitation is mainly concentrated in the period when the echo strength changes from enhancement to gradual reduction,totally about 2 hours. Basically,when VIL are greater than 1.00 kg/m^2 ,the accumulated precipitation tends to exceed 10 mm for every 10 min.

关 键 词：关键词:大暴雨 弱垂直风切变 切变区 露点锋 雷达回波 

分 类 号：P458.121.1[天文地球—大气科学及气象学]