气候变化领域集成服务门户(CCPortal): Subtropical countercurrent variations in cooling climates induced by freshwater forcing over the subarctic North Atlantic

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DOI	10.1007/s00382-018-4293-1
	Subtropical countercurrent variations in cooling climates induced by freshwater forcing over the subarctic North Atlantic
	Zhang C.; Lin X.; Zhang C.; Guo Y.
发表日期	2019
ISSN	0930-7575
起始页码	2799
结束页码	2812
卷号	52 期号:2020-05-06
英文摘要	The subtropical countercurrent (STCC) could affect ocean eddy activity and the atmosphere above. How the STCC varied in a cooling scenario, such as the stadials during the last deglaciation (19–11 ka; ka = 1000 years ago), is still unclear. By 1-Sv (1 Sv = 10 6 m 3 s − 1 ) freshwater hosing over the subpolar North Atlantic to suppress the Atlantic Meridional Overturning Circulation (AMOC), the STCC variations under pre-industrial (PI) and last glacial maximum (LGM, ~ 21 ka) conditions are analyzed. In both hosing experiments, the northern hemisphere cools. The upper ocean becomes less stratified, and the wintertime mixed layer deepens in the Kuroshio–Oyashio extension (KOE) region. As a result, more mode waters (~ 20%) are formed, and they become more vertically uniform. The enhanced mode waters induce a stronger vertical shear and accelerate the STCC based on thermal wind relationship. The strengthened STCC further induces warm ocean temperature and upward air-sea heat flux anomalies along it. While the STCC strengthens in both hosing experiments, the location variations are different. In the PI hosing experiment, the Bering Strait is open. Fresh water enters the North Pacific through the Bering Strait and increases the stratification in the downstream of the KOE region. The mixed layer front shifts westward and induces a robust westward shift of mode waters and the STCC. In the LGM hosing experiment, on the contrast, there is no obvious location shift because the Bering Strait is closed. © 2018, Springer-Verlag GmbH Germany, part of Springer Nature.
英文关键词	Bering strait; Mode waters; Substantially weakened AMOC; Subtropical countercurrent
语种	英语
scopus关键词	air-sea interaction; climate forcing; cooling; countercurrent; eddy; freshwater; heat flux; meridional circulation; mode water; overturn; sea surface temperature; subarctic region; subtropical region; Atlantic Ocean; Atlantic Ocean (North); Bering Strait; 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/146498
作者单位	Physical Oceanography Laboratory/CIMST, Ocean University of China and Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266100, China; First Institute of Oceanography, State Oceanic Administration, Qingdao, 266061, China; Laboratory for Regional Oceanography and Numerical Modeling, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266000, China
推荐引用方式 GB/T 7714	Zhang C.,Lin X.,Zhang C.,et al. Subtropical countercurrent variations in cooling climates induced by freshwater forcing over the subarctic North Atlantic[J],2019,52(2020-05-06).
APA	Zhang C.,Lin X.,Zhang C.,&Guo Y..(2019).Subtropical countercurrent variations in cooling climates induced by freshwater forcing over the subarctic North Atlantic.Climate Dynamics,52(2020-05-06).
MLA	Zhang C.,et al."Subtropical countercurrent variations in cooling climates induced by freshwater forcing over the subarctic North Atlantic".Climate Dynamics 52.2020-05-06(2019).