ECMWF模式强降水预报偏差订正方法研究及应用  

Research and application of bias correction method for heavy rainfall forecast of ECMWF model

作　　者：张娇[1,2] 王东勇[1] 郑淋淋[1] 姚晨[1] 胡玥琦 朱红芳[1] 徐怡 ZHANG Jiao;WANG Dongyong;ZHENG Linlin;YAO Chen;HU Yueqi;ZHU Hongfang;XU Yi(Anhui Meteorological Observatory,Hefei 230031;Anhui Key Lab of Atmospheric Science and Satellite Remote Sensing,Anhui Institute of Meteorological,Hefei 230031;Huangshan Meteorological Bureau of Anhui Province,Huangshan 245000)

机构地区：[1]安徽省气象台,合肥230031 [2]安徽省气象科学研究所,安徽省大气科学与卫星遥感重点实验室,合肥230031 [3]安徽省黄山市气象局,黄山245000

出　　处：《暴雨灾害》2021年第4期430-436,共7页Torrential Rain and Disasters

基　　金：安徽省重点研究和开发计划项目(201904a07020099);中国气象局气象预报业务关键技术发展专项(YBGJXM202002A-09);中国气象局决策气象服务专项经费研究面上项目(JCZX2020007);安徽省气象局新技术集成项目(AHXJ201701);国家青年基金项目(41705029)。

摘　　要：利用安徽省81站逐日降水量资料、NCEP 500 hPa再分析资料、ECMWF(以下简称EC)降水和500 hPa高度预报,基于暴雨中心和天气类型的客观判定,分类统计2012-2018年23个强降水过程降水中心的预报偏差。结果表明在西路强冷空气和东路冷空气天气类型下,当EC预报降水中心位于115°-120°E 584 dagpm线以北时,降水中心预报往往偏北,依据两者的纬度差和降水中心预报偏差建立了基于天气分类的主雨带位置订正方法;同时依据23个强降水过程最大降水区域降水量预报的日平均偏差,建立了暴雨的强度订正方法。将偏差订正方法应用于2020年安徽省梅汛期预报,结果发现无论位置还是强度订正都能使暴雨预报TS评分明显提高。同时进行位置和强度订正后,暴雨TS评分提高更加明显,尤其是对2020年两次最强降水过程订正效果显著。Using the daily precipitation data at 81 stations in Anhui province,NCEP 500 hPa height reanalysis data,EC precipitation and 500 hPa height forecast,on the basis of the objective judgment of rainstorm center and weather type,the forecast bias of precipitation center of 23 heavy precipitation events from 2012 to 2018 is classified and counted.The results show that when the EC forecast precipitation center is located in the north of the 584 dagpm line from 115°E to 120°E,the forecast of precipitation center tends to be biased north.According to the latitude difference between the two and the forecast bias of precipitation center,a correction method of main rain belt position based on weather classification is established.meanwhile,according to the daily averaged biases of the precipitation forecast in the maximum precipitation area of 23 heavy precipitation events,a method for correcting the intensity of rainstorm is established.The bias correction method is applied during the plum flood season in Anhui province in 2020,and the results show that the TS score of rainstorm forecast can be significantly improved regardless of the location or intensity correction.After the correction of both location and intensity,the improvement of TS score is more obvious,especially for the two strongest precipitation events in 2020.

关 键 词：EC暴雨预报 天气分类 降水中心 位置偏差 订正方法 

分 类 号：P456.5[天文地球—大气科学及气象学]