气候变化领域集成服务门户(CCPortal): Ocean–atmosphere coupled Pacific Decadal variability simulated by a climate model

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DOI	10.1007/s00382-020-05248-9
	Ocean–atmosphere coupled Pacific Decadal variability simulated by a climate model
	Luo H.; Zheng F.; Keenlyside N.; Zhu J.
发表日期	2020
ISSN	0930-7575
起始页码	4759
结束页码	4773
卷号	54
英文摘要	Currently, the mechanisms for Pacific Decadal Oscillation (PDO) are still disputed, and in particular the atmosphere response to the ocean in the mid-latitude remains a key uncertainty. In this study, we investigate two potential feedbacks—a local positive and a delayed negative—for the PDO based on a long-term control simulation using the ECHAM5/MPI-OM coupled model, which is selected because of reproduces well the variability of PDO. The positive feedback is as follows. In the PDO positive phase, the meridional sea surface temperature (SST) gradient is intensified and this strengthens the lower level atmospheric baroclinicity in the mid-latitudes, leading to the enhancement of Aleutian low and zonal wind. These atmospheric changes reinforce the meridional SST temperature gradient through the divergence of ocean surface currents. The increased heat flux loss over the anomalously warm water and decreased heat flux loss over the anomalously cold water in turn reinforce the lower atmospheric meridional temperature gradient, baroclinicity and atmospheric circulation anomalies, forming a local positive feedback for the PDO. The delayed negative feedback arises, because the intensified meridional SST gradient also generates an anticyclonic wind stress in the central North Pacific, warming the upper ocean by Ekman convergence. The warm upper ocean anomalies then propagate westward and are transported to the mid-latitudes in the western North Pacific by the western boundary current. This finally reduces the meridional SST gradient, 18 years after the peak PDO phase. These results demonstrate the significant contributions of the meridional SST gradient to the PDO’s evolution. © 2020, Springer-Verlag GmbH Germany, part of Springer Nature.
英文关键词	Barotropic structure; ECHAM5/MPI-OM; Feedback; Meridional SST gradient; PDO
语种	英语
scopus关键词	atmosphere-ocean coupling; barotropic mode; climate feedback; climate modeling; decadal variation; midlatitude environment; Pacific Decadal Oscillation; sea surface temperature; Pacific Ocean; Pacific Ocean (North)
来源期刊	Climate Dynamics
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/145453
作者单位	International Center for Climate and Environment Science (ICCES), Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing, 100029, China; Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, 519082, China; South China Sea Institution and School of Atmospheric Sciences, Sun Yat-sen University, Zhuhai, 519082, China; Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters, Nanjing University of Information Science and Technology, Nanjing, 210044, China; Center for Ocean Mega-Science, Chinese Academy of Sciences, Qingdao, 266071, China; Geophysical Institute, University of Bergen/Bjerknes Center for Climate Research, Bergen, 5007, Norway; Nansen Environmental and Remote Sensing Center/Bjerknes Center for Climate Research, Bergen, 5006, Norway; University of the Chinese Academy of Sciences, Beijing, 100049, China
推荐引用方式 GB/T 7714	Luo H.,Zheng F.,Keenlyside N.,等. Ocean–atmosphere coupled Pacific Decadal variability simulated by a climate model[J],2020,54.
APA	Luo H.,Zheng F.,Keenlyside N.,&Zhu J..(2020).Ocean–atmosphere coupled Pacific Decadal variability simulated by a climate model.Climate Dynamics,54.
MLA	Luo H.,et al."Ocean–atmosphere coupled Pacific Decadal variability simulated by a climate model".Climate Dynamics 54(2020).