甘南高原短时强降水潜势预报研究和雷达回波分析  

Potential Forecast Research and Radar Echo Analysis of Short-time Strong Rainfall in Gannan Plateau

作　　者：吉哲君 安华银 何涛 陈洋 赵惠珍 罗王军 

机构地区：[1]甘肃省甘南藏族自治州气象局,甘肃合作747000

出　　处：《现代农业科技》2016年第14期197-200,共4页Modern Agricultural Science and Technology

基　　金：甘肃省气象局课题"高原强对流天气雷达指标研究"

摘　　要：利用甘南州8个国家气象观测站和146个乡镇区域自动气象站2011—2012年5—9月降水观测资料,风云2E红外云图资料和合作、武都高空站高空观测资料,对甘南高原短时强降水天气的特征进行分析,建立了甘南州短时强降水过程的天气尺度和中尺度概念模型和甘南州分县短时强降水潜势预报方程。同时利用2013—2014年甘南新一代天气雷达资料对甘南高原短时强降水多普勒雷达回波特征进行统计分析。结果表明:5—9月甘南州各县市均可发生短时强降水,8月是短时强降水发生频次最高的月份,5月和7月次之,6月和9月相对较少。按照环流形势甘南高原短时强降水过程可以分为高原低槽切变型、槽后西北气流型和高压内部型3种类型。甘南短时强降水云顶亮温值在8月达到最低。甘南短时强降水大部分个例回波强度大于20 dbz,回波顶高度在3 km以上,垂直液态含水量在5 kg/m2,77%的短时强降水速度场有明显的辐合和中气旋。Based on the observation rain data of 8 national stations and 146 regional automatic meteorological stations from May to September in2011—2012 and IR image data by FY-2E and upper-air observation data in Wudu Station,the characteristics of the short-time strong rainfall was analyzed.The conceptual model of both synoptic scale and meso-scale rainfall was established,the respective potential forecasting equations of the short-time strong rainfall was build corresponding to each county in Gannan.The Statistic and Analysis of Doppler radar echo by new weather radar at Gannan plateau form 2013 to 2014 were made at the same time.The results showed that the short-time strong rainfall occurs in all counties of Gannan from May to September and the highest frequency of the short-time strong rainfall occurrence was in October,and followed by May and July,and the least in June and September.According to the large scale circulation situation,the processes models of the short-time strong rainfall in Gannan plateau could be classified three patterns ：pressure trough shear on the Qinghai-Xizang Plateau,northwesterly air flow after the trough and high-pressure internal field.The TBB value of cloud in which the short-time strong rainfall took place hit bottom in August.The echo intensity of the most cases was greater than 20 dbz,the top of the echo was higher than 3 km and the vertical liquid water content was about 5 kg/m2 and there existed apparent convergence and mesocyclone in velocity field in about 77 percent of the short-time strong rainfalls.

关 键 词：短时强降水 潜势预报 雷达回波 甘南高原 

分 类 号：P456[天文地球—大气科学及气象学]