CMIP6全球气候模式对青藏高原中东部地表感热通量模拟能力评估  

Assessment of the Spring Sensible Heat Flux over the Central and Eastern Tibetan Plateau Simulated by CMIP6 Multi-models

作　　者：王美蓉[1,2] 周顺武[1] 孙阳 王军 马淑俊 余忠水[5] WANG Meirong;ZHOU Shunwu;SUN Yang;WANG Jun;MA Shujun;YU Zhongshui(Joint Center for Data Assimilation Research and Applications/Key Laboratory of Meteorological Disaster,Ministry of Education(KLME)/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC-FEMD)/Joint International Research Laboratory of Climate and Environment Change(ILCEC),Nanjing University of Information Science&Technology,Nanjing 210044;State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics,Institute of Atmospheric Physics,Chinese Academy of Sciences,Beijing 100029;International Institute for Earth System Science,Nanjing University,Nanjing 210023;Lhasa Municipal Meteorological Bureau,Lhasa 850011;Atmospheric Environment Science Research Institute of Tibet Plateau,Tibet Meteorological Administration,Lhasa 850000)

机构地区：[1]南京信息工程大学资料同化研究与应用中心/气象灾害教育部重点实验室/气象灾害预报预警与评估协同创新中心/气候与环境变化国际合作联合实验室,南京210044 [2]中国科学院大气物理研究所大气科学和地球流体力学数值模拟国家重点实验室,北京100029 [3]南京大学国际地球系统科学研究所,南京210023 [4]拉萨市气象局,拉萨850011 [5]西藏自治区气象局西藏高原大气环境科学研究所,拉萨850000

出　　处：《大气科学》2022年第5期1225-1238,共14页Chinese Journal of Atmospheric Sciences

基　　金：国家自然科学基金项目41807434、41605039;中国气象局气象软科学项目2022ZDIANXM28。

摘　　要：利用青藏高原(以下简称高原)气象台站常规观测资料、国家青藏高原科学数据中心的青藏高原地气相互作用过程高分辨率(逐小时)综合观测数据集(2005~2016)、国际耦合模式比较计划第六阶段(CMIP6)的历史模拟试验数据和卫星辐射资料,定量评估了12个全球气候模式对1979~2014年高原中东部地表感热通量的模拟能力,并对其模拟偏差进行了成因分析。结果表明,CMIP6模式可较好地重现高原地表感热通量的年循环和季节平均的空间分布型,但数值较计算感热通量偏低,主要表现为对感热通量大值区严重低估。区域平均而言,12个模式模拟的春季高原中东部感热通量的时间演变序列整体较计算感热通量偏低,其中偏差最大的模式为MIROC6,其多年均值仅为计算值的1/3左右。进一步分析发现多模式模拟的春季高原10 m高度处风速和地气温差分别偏强和偏弱,说明CMIP6模拟的春季高原感热通量偏低可主要归因于地气温差的模拟冷偏差。地气温差的模拟冷偏差在高原中东部地区普遍存在,且地表温度和空气温度均存在明显冷偏差,尤其地表温度偏差更大,这很大程度上可能与CMIP6多模式模拟的春季高原降水偏强有关。On the basis of historical observations at 77 meteorological stations and a long-term dataset of integrated land–atmosphere interaction observations on the Tibetan Plateau(TP)(2005–2016),the historical simulations of the 12models that participated in CMIP6(the sixth phase of the coupled model intercomparison project),and GEWEX-SRB satellite radiation products,the authors have quantitatively examined the ability of CMIP6 models to simulate the surface sensible heat flux over the TP during 1979–2014 and analyzed the possible causes of simulation biases.The results show that CMIP6 models can well reproduce the annual cycle and seasonal spatial patterns of the sensible heat over the TP,albeit with lower amplitudes than the calculated sensible heat flux,particularly showing obvious underestimation over the strong,sensible heat regions.The area-weighted long-term spring sensible heat fluxes over the central and eastern TP simulated by the 12 models are generally lower than calculated values,with the minimum sensible heat amplitude in the MIROC6 simulation,which has approximately 1/3 of the climatological amplitude in calculated sensible heat flux.Furthermore,the authors find that the wind speed at 10-m height and the springtime land–air temperature difference simulated by models are larger and smaller than the calculated values,respectively,implying that the lower sensible heat amplitudes simulated by CMIP6 multi-models are mainly due to the cold biases of the land–air temperature difference.Spatially,the cold biases of the land–air temperature difference widely exist over the central and eastern TP,in which,more specifically,the surface and air temperatures show the cold biases but with colder biases in surface temperature.The cold biases mechanistically are likely related to the simulated stronger precipitation over the TP in CMIP6 models.

关 键 词：青藏高原 CMIP6模式 地表感热通量 地气温差 冷偏差 

分 类 号：P467[天文地球—大气科学及气象学]