ERA5再分析资料对甘肃省近地面风速气候特征及变化趋势再现能力的评估  

Evaluation of the ERA5 Reanalysis Data on the Near-Surface Wind Speed Climate Characteristics and Change Trend Reproduction Ability in Gansu Province

作　　者：马绎皓 毛睿[3] 杨阳 马莉 苟尚 MA Yihao;MAO Rui;YANG Yang;MA Li;GOU Shang(Faculty of Geographical Science,Beijing Normal University,Beijing 100875,China;Lanzhou Central Meteorological Observatory,Lanzhou 730020,Gansu,China;School of National Safety and Emergency Management,Beijing Normal University,Beijing 100875,China;Lanzhou Institute of Arid Meteorological,China Meteorological Administration,Lanzhou 730020,Gansu,China)

机构地区：[1]北京师范大学地理科学学部,北京100875 [2]兰州中心气象台,甘肃兰州730020 [3]北京师范大学国家安全与应急管理学院,北京100875 [4]中国气象局兰州干旱气象研究所,甘肃兰州730020

出　　处：《高原气象》2023年第1期210-220,共11页Plateau Meteorology

基　　金：国家重点研究与发展项目(2020YFA0608201);国家自然科学基金项目(41730639);甘肃省青年科技基金项目(20JR10RA451)。

摘　　要：为了探究ERA5再分析资料对甘肃省近地层风速的再现能力,利用甘肃省1981-2020年80个国家级气象台站的地面风速资料,分析了近40年间甘肃省风速变化情况,并比较了第五套欧洲中期天气预报中心再分析资料(ERA5)与观测资料变化趋势的异同,讨论了其对甘肃省地面风速的再现能力。结果表明,甘肃省四季平均地面风速自西向东逐渐减小,地面风速最大季节均为春季,不同地区风速偏小季节有所差异;近40年地面风速的变化整体上趋于平稳,但各站点春季风速以显著下降趋势为主,其余三个季节以上升趋势居多;在20世纪90年代初以前四季平均风速均呈现减小趋势,春季变化趋势最强,秋季变化趋势最弱,之后转为平稳变化或上升趋势,冬、夏两季风速上升趋势较强。ERA5再分析资料对甘肃省风速月际变化和主要季节特征的再现能力较好,但对各季节平均风速值和风速长期变化趋势的再现能力较差,仅在风速下降时期有较好的再现能力,并且ERA5风速资料也不具备再现甘肃省各季节风速长期趋势的能力;ERA5再分析资料不能直接用于估算甘肃省的风能密度,但对其进行线性偏差订正后,在风能密度的多年平均值方面有较好的再现能力。In order to explore the reanalysis data of ERA5’s ability to reproduce wind speed in the surface layer of Gansu Province, this paper uses the surface wind speed data of 80 national meteorological stations in Gansu Province from 1981 to 2020 to analyze the wind speed changes in Gansu Province in the past 40 years, by comparing the similarities and differences between the fifth set of European Center for Mid-range Weather Forecast(ERA5) and the change trend of observational data, its ability to reproduce the surface wind speed in Gansu province is discussed. The result shows: The average surface wind speed in the four seasons in Gansu Province gradually decreases from west to east, the season with the highest surface wind speed is spring, and the seasons with low wind speed vary in different regions;The change of surface wind speed in the past 40 years has generally stabilized, However, the spring wind speed at each site mainly showed a significant downward trend, and the other three seasons mostly showed an upward trend;Before the early 1990s, the average wind speed in the four seasons showed a decreasing trend, with the strongest change trend in spring and the weakest change trend in autumn, after that, it turned to a stable change or an upward trend, and the upward trend of wind speed in winter and summer was stronger. The ERA5 reanalysis data has good reproducibility for the inter month variation of wind speed and main seasonal characteristics in Gansu Province, but poor reproducibility for the seasonal average wind speed value and long-term variation trend of wind speed, and it only performs well in the period of wind speed decline, and the ERA5 wind speed data does not have the ability to reproduce the long-term trend of wind speed in Gansu Province in each season;The ERA5 reanalysis data cannot be directly used to estimate the wind energy density in Gansu Province, but after correcting the linear deviation, it has a good reproducibility in terms of the multi-year average value of wind energy density.

关 键 词：甘肃 ERA5 风速变化 再现能力 

分 类 号：P425.44[天文地球—大气科学及气象学]