ECMWF模式在恩施山区强降水预报中的偏差订正方法  

Deviation correction method of ECMWF model for heavy precipitation forecast in Enshi mountain area

作　　者：谭艳立 虞列辉 郑翔天 吴松 Tan Yanli;Yu Liehui;Zheng Xiangtian;Wu Song(Enshi Tujia and Miao Autonomous Prefecture Meteorological Bureau,Enshi 445000)

机构地区：[1]恩施土家族苗族自治州气象局,恩施445000

出　　处：《气象水文海洋仪器》2024年第5期5-8,共4页Meteorological,Hydrological and Marine Instruments

基　　金：湖北省恩施州气象局科技发展基金面上项目(202101)资助。

摘　　要：为了提高暴雨的预报准确率,文章利用恩施土家族苗族自治州342个区域气象站逐日降水资料,EC细网格降水、风场和湿度场预报资料,分类统计2013-2021年共49次强降水过程影响系统类型,并分析其面雨量强度和强降水中心位置偏差。结果表明:恩施土家族苗族自治州区域强降水影响系统分为低涡东移类、冷切南压类、暖切类、低涡切变类及不典型风场类,其中冷切南压类和暖切类降水系统占据了所有强降水影响系统的62%;将各类降水系统的实况与预报场进行对比分析,根据各类降水类型面雨量强度和强中心位置的偏差建立了相应的偏差订正方法;应用2022年4次强降水过程检验偏差订正方法,发现虽然不是每一次过程订正后都能达到完全理想的结果,但都能减少预报偏差,面雨量强度预报和强降水中心位置预报订正均符合天气学规律。研究结果为提升恩施山区强降水预报水平提供支持。In order to improve the prediction accuracy of rainstorm,this paper uses the daily precipitation data of 342 regional meteorological stations in Enshi Tujia and Miao Autonomous Prefecture,and the forecast data of EC fine grid precipitation,wind field and humidity field to classify and count the impact system types of 49 strong precipitation processes from 2013 to 2021,and analyzes the area rainfall intensity and the deviation of the location of the strong precipitation center.The results show that the impact systems of heavy precipitation in Enshi Tujia and Miao Autonomous Prefecture can be divided into three categories:eastward movement of low eddies,southward pressure of cold shear,warm shear of low eddies,and atypical wind fields.Among them,the southward pressure of cold shear and warm shear precipitation systems account for 62%of all heavy precipitation impact systems.A comparative analysis was conducted between the actual and forecast fields of various precipitation systems,and corresponding deviation correction methods were established based on the deviation of surface rainfall intensity and strong center position of various precipitation types.By applying the bias correction method for four heavy precipitation processes in 2022,it was found that although not every process correction could achieve completely ideal results,it could reduce forecast deviation.The correction of surface rainfall intensity forecast and heavy precipitation center location forecast were in line with the laws of meteorology.The research results provide support for improving the level of heavy precipitation forecasting in Enshi mountainous areas.

关 键 词：ECMWF模式 恩施山区 强降水 偏差订正 

分 类 号：P456.1[天文地球—大气科学及气象学]