Variability of the Pacific subtropical cells under global warming in CMIP6 models

作     者：Xue HAN Junqiao FENG Yunlong LU Dunxin HU Xue HAN;Junqiao FENG;Yunlong LU;Dunxin HU

作者机构：Key Laboratory of Ocean Circulation and WavesChinese Academy of SciencesQingdao 266071China Institute of OceanologyChinese Academy of SciencesQingdao 266071China University of Chinese Academy of SciencesBeijing 100049China Center for Ocean Mega-ScienceChinese Academy of SciencesQingdao 266071China Laboratory for Ocean Dynamics and ClimatePilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China 

出 版 物：《Journal of Oceanology and Limnology》 (海洋湖沼学报（英文）)

年 卷 期：2024年第42卷第1期

页      面：24-40页

核心收录：

学科分类：0710[理学-生物学] 07[理学] 0707[理学-海洋科学] 0706[理学-大气科学] 

基　　金：the National Natural Science Foundation of China(NSFC)(No.41976027)。 

主　　题：interior subtropical cell(STC) global warming Coupled Model Inter-comparison Project(CMIP6) western boundary transport 

摘      要：The Pacific subtropical cells(STCs)are shallow meridional overturning circulations connecting the tropics and subtropics,and are assumed to be an important driver of the tropical Pacific decadal variability.The variability of STCs under global warming is investigated using multimodal outputs from the latest phase of the Coupled Model Inter-comparison Project(CMIP6)and ocean reanalysis products.Firstly,the volume transport diagnostic analysis is employed to evaluate how coupled models and ocean reanalysis products reproduce interior STC transport.The variation of heat transport by the interior STC under the high-emissions warming scenarios is also analyzed.The results show that the multimodal-mean linear trends of the interior STC transport along 9°S and 9°N are-0.02 Sv/a and 0.04 Sv/a under global warming,respectively,which is mainly due to the combined effect of the strengthened upper oceanic stratification and the weakening of wind field.There is a compensation relationship between the interior STC and the western boundary transport in the future climate,and the compensation relationship of 9°S is more significant than that of 9°N.In addition,compared with ocean reanalysis products,the coupled models tend to underestimate the variability of the interior STC transport convergence,and thus may lose some sea surface temperature(SST)driving force,which may be the reason for the low STC-SST correlation simulated by the model.The future scenario simulation shows that the heat transport of interior STC is weakened under global warming,with a general agreement across models.