CLDAS实况产品在陕西气温网格预报检验与订正中的应用  

Application of CLDAS in Test and Correction of Grid Temperature Forecast in Shaanxi Province

作　　者：王丹 王建鹏 党超琪[1] 娄盼星 黄少妮 蔡新玲[5] WANG Dan;WANG Jianpeng;DANG Chaoqi;LOU Panxing;HUANG Shaoni;CAI Xinling(Shaanxi Meteorological Service Center,Xi’an 710014;Xi’an Meteorological Bureau,Xi’an 710016;Key Laboratory of Eco-Environment and Meteorology for The Qinling Mountains and Loess Plateau,Shaanxi Meteorological Service,Xi’an 710016;Shaanxi Meteorological Observatory,Xi’an 710014;Shaanxi Climate Center,Xi’an 710014)

机构地区：[1]陕西省气象服务中心,西安710014 [2]西安市气象局,西安710016 [3]陕西省气象局秦岭和黄土高原生态环境气象重点实验室,西安710016 [4]陕西省气象台,西安710014 [5]陕西省气候中心,西安710014

出　　处：《气象》2023年第8期946-957,共12页Meteorological Monthly

基　　金：陕西省重点研发计划(2021SF-476、2023-YBSF-235);陕西省气象局精细化气象格点预报攻关团队共同资助。

摘　　要：利用陕西地区自动气象站的气温观测资料,采用滑动训练期和一元线性回归方法,先在站点上对中国气象局陆面数据同化系统(CLDAS)气温进行检验和订正,再将订正系数传递到格点上订正CLDAS气温格点场,最后利用站点观测气温和订正前、后的CLDAS气温分别对ECMWF气温预报的格点场进行订正,并做非独立和独立检验。结果表明,CLDAS气温的空间分布特征与站点观测基本一致,但是存在一定误差,订正后误差减小,其中,订正前秦岭和大巴山区的平均绝对误差较其他地区偏大,绝对误差≤1℃和≤2℃的准确率分别低于20%和30%,订正后均提高了40%以上。利用订正后的CLDAS气温对ECMWF气温预报进行订正,提高了模式的预报准确率,例如,陕西地区24 h日最高和最低气温预报的绝对误差≤2℃的准确率分别从订正前的46%和66%提高到订正后的63%和74%,优于利用站点观测气温和订正前的CLDAS气温对欧洲中期天气预报中心(ECMWF)气温预报的订正结果,一定程度上改进了模式在站点稀少地区的气温预报质量,用于高分辨率气象格点预报业务效果更好。Based on air temperature observation data of automatic weather stations in Shaanxi Province,by using sliding training period and unitary linear regression methods,air temperature from CMA Land Data Assimilation System(CLDAS)is tested and corrected at stations,then the correction coefficient is interpolated to grid point to revise CLDAS temperature at the grid.Finally,temperature forecast from European Centre for Medium-Range Weather Forecasting(ECMWF)is corrected by respectively using the air temperature data from observation and CLDAS before and after correcting,which is tested by non-independent and independent validations.The results show that spatial distribution characteristics of temperature from CLDAS are basically consistent with those from station observations,but there are some errors between them,which can be reduced by correcting with observation data.The accuracies of absolute error less than 1℃or 2℃of CLDAS temperature before correcting are respectively less than 20%and 30%in Qinling and Daba Mountains,where accuracies are smaller than in other areas and are improved by more than 40%after correction.The CLDAS grid temperature data after correcting are used to correct the temperature prediction of ECMWF improving the accuracy of the model forecasts.It also improves the temperature forecast quality of ECMWF in the areas with few weather stations,and is suitable for high resolution meteorological grid forecast.The accuracies of absolute error less than 2℃for daily maximum and minimum temperatures with 24 h lead time are increased from 46%and 66%before correcting to 63%and 74%after correcting in Shaanxi Province.These correction effects are higher than accuracies of the temperature forecast corrected by using air temperature data from observation and unrevised CLDAS.

关 键 词：气温 中国气象局陆面数据同化系统(CLDAS) 检验 误差订正 

分 类 号：P413[天文地球—大气科学及气象学] P456