天津地区冬季降水相态识别判据研究  

Study and Application of Discriminant Criterion of WinterPrecipitation Phase in Tianjin

作　　者：陈宏[1] 余文韬[1] 徐威 杨晓君[1] 孙建元[1] 陈凯华[2] CHEN Hong;YU Wentao;XU Wei;YANG Xiaojun;SUN Jianyuan;CHEN Kaihua(Tianjin Meteorological Observatory,Tianjin 300074,China;Tianjin Meteorological Information Center,Tianjin 300074,China)

机构地区：[1]天津市气象台,天津300074 [2]天津市气象信息中心,天津300074

出　　处：《干旱气象》2021年第4期670-677,共8页Journal of Arid Meteorology

基　　金：国家自然科学基金项目(41575049);天津市自然科学基金项目(16JQNJC07500);天津市气象局项目(201804lxxm01,202009ybxm03);中国气象局预报员专项(CMAYBY2020-008);2021年中国气象局创新发展专项共同资助。

摘　　要：利用2000—2015年10月至次年4月天津地区逐日常规气象观测资料和ERA-Interim再分析资料(0.125°×0.125°),对天津地区发生的3种降水相态转换(雨转雨夹雪再转雪)的天气过程进行统计,分析降水相态转换过程中温度、湿度和不同等压面厚度特征,得到与降水相态转换关系密切的9种判别因子:850 hPa温度(T 850)、925 hPa温度(T 925)、1000 hPa温度(T 1000)、地面温度(T s)、1000~850 hPa位势厚度(H 1000-850)、850~700 hPa位势厚度(H 850-700)、0℃层高度、-4℃层高度和925 hPa相对湿度,给出每种因子对应不同降水相态的阈值,并通过3次天气个例进一步验证指标的可用性。在此基础上,综合利用9个判别因子和阈值指标建立降水相态判别方程,经检验发现雨和雪回代检验判别准确率达80%以上。Based on conventional meteorological observation data in Tianjin and the ECWMF ERA-Interim reanalysis data(0.125°×0.125°),the transformation processes of rain-to-sleet and then sleet-to-snow were analyzed from October to next April during 2000-2015 in Tianjin.The humidity and geopotential thickness during the transformation process of precipitation phases were analyzed,and 9 factors,namely temperature on 850 hPa,925 hPa,1000 hPa and surface,thickness from 1000 to 850 hPa and from 850 to 700 hPa,0℃layer height,-4℃layer height and 925 hPa relative humidity,were identified,which had close relationship with transformation process of precipitation phases.Further,their corresponding threshold indexes for different precipitation phases were given.And through the analysis of 3 weather cases,the usability of the indicators had been further verified.The discriminant equation for precipitation phases was established by using the 9 factors,it was found that the backtesting discriminant accuracy for rain and snow was higher than 80%.

关 键 词：降水相态 判别因子 阈值 检验 

分 类 号：P456[天文地球—大气科学及气象学]