气候变化领域集成服务门户(CCPortal): Modelled response of Arctic and North Atlantic thermohaline structure and circulation to the prolonged unidirectional atmospheric forcing over the Arctic Ocean

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DOI	10.1007/s00382-024-07239-6
	Modelled response of Arctic and North Atlantic thermohaline structure and circulation to the prolonged unidirectional atmospheric forcing over the Arctic Ocean
	Ivanov, Vladimir; Gusev, Anatoly; Diansky, Nikolay; Sukhonos, Pavel
发表日期	2024
ISSN	0930-7575
EISSN	1432-0894
英文摘要	In this model study, we address the probability of rapid reorganization of thermohaline structure and circulation in the Arctic (AO) and North Atlantic (NA) oceans under the prolonged unidirectional atmospheric forcing over the AO. The relevance of such investigation is dictated by the presence of huge volume of surplus fresh water accumulated in the Beaufort Gyre (BG) of the Canada Basin for the past 30 years due to extremal sea ice melting and increased river runoff. In hypothetical case of rapid release to the NA, this fresh water volume may at least cause strong salinity anomaly similar to the Great Salinity Anomaly in the 1970s. Taking into account that the subpolar NA is the key locus of the deep water formation feeding the southward branch of the Atlantic Meridional Overturning Circulation (AMOC), the excess freshening at the ocean surface may negatively affect the AMOC intensity. To check up the validity of this hypothesis, we carried out the two idealized model experiments with opposite atmospheric forcings over the AO: the so-called cyclonic one, which favors intensive NA-AO water exchange, and the anticyclonic one, which impedes such an exchange. We chose the two actual years with extremal forcings (1989 as a cyclonic one, and 2004 as an anticyclonic one) and artificially applied them for the 10-year period assuming that such a duration is at the margin of physical realism. Our major finding, within the limitations of numerical experiments on the OGCM (Ocean General Circulation Model) INMOM (Institute of Numerical Mathematics Ocean Model), shows that anomalously long preservation of cyclonic forcing over the AO is able to substantially rearrange salinity in the upper ocean layer. However, it may not trigger massive instant outflow of freshwater through the Fram and Denmark Straits, since a large portion of accumulated in the BG freshwater spreads around the AO following the surface circulation pattern without reaching the Fram Strait. However, the tendency of the upper ocean layer freshening in the subpolar NA due to freshwater flushing from the AO is confirmed.
英文关键词	Global circulation conveyor; Ocean currents; Water masses; Heat and mass exchange; Sea ice; Climate change; Thermohaline catastrophe
语种	英语
WOS研究方向	Meteorology & Atmospheric Sciences
WOS类目	Meteorology & Atmospheric Sciences
WOS记录号	WOS:001214949300009
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/305595
作者单位	Lomonosov Moscow State University; Russian Academy of Sciences; Zubov State Oceanographic Institute; Russian Academy of Sciences; Shirshov Institute of Oceanology; Russian Academy of Sciences; Institute of Natural & Technical Systems of the RAS
推荐引用方式 GB/T 7714	Ivanov, Vladimir,Gusev, Anatoly,Diansky, Nikolay,et al. Modelled response of Arctic and North Atlantic thermohaline structure and circulation to the prolonged unidirectional atmospheric forcing over the Arctic Ocean[J],2024.
APA	Ivanov, Vladimir,Gusev, Anatoly,Diansky, Nikolay,&Sukhonos, Pavel.(2024).Modelled response of Arctic and North Atlantic thermohaline structure and circulation to the prolonged unidirectional atmospheric forcing over the Arctic Ocean.CLIMATE DYNAMICS.
MLA	Ivanov, Vladimir,et al."Modelled response of Arctic and North Atlantic thermohaline structure and circulation to the prolonged unidirectional atmospheric forcing over the Arctic Ocean".CLIMATE DYNAMICS (2024).