HRCLDAS与ERA5-Land气温日统计数据在山东地区的对比评估

Comparison and evaluation of HRCLDAS and ERA5-Land daily temperature statistics in Shandong

基于山东省2021年3月—2022年2月1519个气象观测站2 m气温观测数据,对中国气象局高分辨率陆面数据同化系统(High Resolution China Meteorological Administration Land Data Assimilation System,HRCLDAS)和欧洲中期天气预报中心第五代陆面再分析数据集(ERA5-Land)逐小时2 m气温分析的日统计数据(平均气温、最高气温、最低气温)进行对比评估。结果显示:(1)HRCLDAS/ERA5-Land日统计平均气温、最高气温、最低气温的均方根误差分别为0.1/1.2℃、0.6/1.9℃、0.4/1.7℃,表明HRCLDAS具有更高的精度,且在不同地理区域、不同海拔高度的表现均优于ERA5-Land,大部地区的偏差(-0.5~0.5℃)远低于ERA5-Land(-2.0~2.0℃)。(2)两套数据对高温及寒潮过程的监测能力对比评估表明,HRCLDAS能够捕捉到大部分的高温以及寒潮过程,其与观测的高温日数及寒潮日数空间分布较为相似,但对影响范围存在一定的低估;ERA5-Land则只能监测到部分高温及寒潮过程,并对高温日数与寒潮日数存在严重的低估。

Based on the 2-m air temperature data of 1519 meteorological observation stations in Shandong from March 2021 to February 2022,the applicability of the 2-m temperature daily statistics(mean,maximum,and minimum temperature)from HRCLDAS(High Resolution China Meteorological Administration Land Data Assimilation System)and ERA5-Land(ECMWF Reanalysis v5-Land)in Shandong is compared and evaluated.The results are as follows.(1)The RMSE(root mean square error)of mean,maximum,and minimum temperature from HRCLDAS/ERA5-Land daily statistics is 0.1/1.2℃,0.6/1.9℃,and 0.4/1.7℃,respectively,which means that HRCLDAS is more accurate,and HRCLDAS in different geographical areas and at different altitudes performs better than ERA5-Land.The deviation of HRCLDAS in most areas(-0.5 to 0.5℃)is much lower than that of ERA5-Land(-2.0 to 2.0℃).(2)The comparison and evaluation of the two datasets on the monitoring ability of high temperature and cold wave show that HRCLDAS can capture most of the high temperature and cold wave processes,and the spatial distribution of the number of high temperature and cold wave days is similar to the observation,but it somewhat underestimates the influence range.However,ERA5-Land can only monitor part of the high temperature and cold wave processes,and the number of high temperature and cold wave days is seriously underestimated.