摘要
本研究首先基于1961-2020年观测和再分析的5种风速资料,分析了近60年来青藏高原地区地表风速变化特征。随后,使用区域气候模式动力降尺度的5个模拟结果及其集合平均,检验评估了其对1986-2005年青藏高原地表风速的模拟能力。基于多源数据的分析结果表明,1961-2002年青藏高原地区的季节和年平均地表风速为下降趋势,但数值上存在差异,CN05.1和NCEP-1的风速在2002-2020年表现为增大。无风(0.0~0.2 m·s^(-1))的概率变化较小,在1961-2002年和2002-2020年以微弱的减少趋势为主,软风(0.3~1.5 m·s^(-1))和轻风(1.6~3.3 m·s^(-1))在1961-2002年增加,2002-2020年减少,微风(3.4~5.4 m·s^(-1))与和风(5.5~7.9 m·s^(-1))则基本表现出与平均风速类似的变化特征,大风(≥8 m·s^(-1))在1961-2002年和2002-2020年均以减小趋势为主。总体来说,CN05.1表现出与适用性较好的JRA-55再分析数据相一致的特征,并且和站点资料更为吻合,表明该格点化风速观测数据在高原地区具有良好的适用性。动力降尺度的评估结果发现,所有模拟结果均可以合理地再现出CN05.1中地表风速在不同季节的空间分布,并且可以很好地模拟出不同地形区的风速差异,但仍存在对高原西北部风速模拟偏小,以及其他区域模拟偏大的误差。模式对高原地表风速年内变化的模拟也存在不足,模拟的变化趋势值普遍偏小。同时,集合平均的相对均方根误差最小,总体较单个模拟结果稳定。
In the context of global warming,the in-depth study of the change in surface wind speed over Qinghai-Xizang Plateau can provide support for development planning for the double-carbon policy.Based on the multi-source datasets,it is expected to obtain the qualitative conclusion.In addition,to comprehensive evaluate the performance of CN05.1 gridded dataset as well as the dynamical downscaling simulations can provide guidance for the application of these two datasets over this region.Firstly,the monthly,seasonal and annual averaged wind speed,inter-annual,intra-annual variability of surface wind speed,the trends of wind speed probability for different grades,as well as the spatial distribution over Qinghai-Xizang Plateau were analyzed,based on the five wind speed datasets from 1961 to 2020.Then,the performance in reproducing the monthly,seasonal,annual averaged and long-term variability of surface wind speed from 1986 to 2005 was evaluated,using the five dynamical downscaling simulations and their ensemble mean from regional climate model(RegCM4).The result indicated that decreasing trends were generally found in the seasonal and annual averaged surface wind speed from 1961 to 2002,with different magnitude among different datasets,while for the period from 2002 to 2020,the significant increasing trend was observed both in CN05.1 and NCEP-1.In addition,the probability of calm wind(0.0~0.2 m·s^(-1))showed a slightly decrease both in 1961-2002 and 2002-2020.The light air(0.3~1.5 m·s^(-1))and light breeze(1.6~3.3 m·s^(-1))increased in 1961-2002 and decreased in 2002-2020,in the meantime,the gentle breeze(3.4~5.4 m·s^(-1))and moderate breeze(5.5~7.9 m·s^(-1))showed a similar change to the mean surface wind speed.Furthermore,the wind speed greater than or equal to 8 m·s^(-1) mainly decreased in 1961-2002 and 2002-2020.Overall,the change in CN05.1 was more closed to station dataset and showed consistent characteristics with JRA-55,which behaved better among reanalysis datasets,indicating the high applicability of CN0
作者
吴佳
吴婕
闫宇平
WU Jia;WU Jie;YAN Yuping(National Climate Center,Beijing 100081,China;School of Geography and Environmental Engineering,Gannan Normal University,Ganzhou 341000,JiangXi,China)
出处
《高原气象》
CSCD
北大核心
2022年第4期963-976,共14页
Plateau Meteorology
基金
国家重点研发计划项目(2018YFB1502803)
国家自然科学基金项目(41805074)
第二次青藏高原综合科学考察研究项目(2019QZKK010315)
中国长江三峡集团有限公司项目(0704181)。
关键词
青藏高原
风速变化
动力降尺度
评估
Qinghai-Xizang Plateau
surface wind speed change
dynamical downscaling
evaluation
