气候变化领域集成服务门户(CCPortal): Impact of ocean resolution and mean state on the rate of AMOC weakening

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DOI	10.1007/s00382-020-05345-9
	Impact of ocean resolution and mean state on the rate of AMOC weakening
	Jackson L.C.; Roberts M.J.; Hewitt H.T.; Iovino D.; Koenigk T.; Meccia V.L.; Roberts C.D.; Ruprich-Robert Y.; Wood R.A.
发表日期	2020
ISSN	0930-7575
起始页码	1711
结束页码	1732
卷号	55
英文摘要	We examine the weakening of the Atlantic Meridional Overturning Circulation (AMOC) in response to increasing CO2 at different horizontal resolutions in a state-of-the-art climate model and in a small ensemble of models with differing resolutions. There is a strong influence of the ocean mean state on the AMOC weakening: models with a more saline western subpolar gyre have a greater formation of deep water there. This makes the AMOC more susceptible to weakening from an increase in CO2 since weakening ocean heat transports weaken the contrast between ocean and atmospheric temperatures and hence weaken the buoyancy loss. In models with a greater proportion of deep water formation further north (in the Greenland-Iceland-Norwegian basin), deep-water formation can be maintained by shifting further north to where there is a greater ocean-atmosphere temperature contrast. We show that ocean horizontal resolution can have an impact on the mean state, and hence AMOC weakening. In the models examined, those with higher resolutions tend to have a more westerly location of the North Atlantic Current and stronger subpolar gyre. This likely leads to a greater impact of the warm, saline subtropical Atlantic waters on the western subpolar gyre resulting in greater dense water formation there. Although there is some improvement of the higher resolution models over the lower resolution models in terms of the mean state, both still have biases and it is not clear which biases are the most important for influencing the AMOC strength and response to increasing CO2. © 2020, The Author(s).
英文关键词	AMOC; Climate; Resolution; Weakening
语种	英语
scopus关键词	air temperature; air-sea interaction; atmosphere-ocean coupling; carbon dioxide; climate modeling; deep water formation; heat transfer; meridional circulation; overturn; sea surface temperature; Arctic; Atlantic Ocean; Greenland; Iceland; Norway
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/145337
作者单位	Met Office Hadley Centre, Exeter, United Kingdom; Centro Euro-Mediterraneo sui Cambiamenti Climatici, Bologna, Italy; Swedish Meteorological and Hydrological Institute, Norrköping and Bolin Centre for Climate Research, Stockholm, Sweden; Institute of Atmospheric Science and Climate (ISAC-CNR), Bologna, Italy; ECMWF, Reading, United Kingdom; Barcelona Supercomputing Center, Barcelona, Spain
推荐引用方式 GB/T 7714	Jackson L.C.,Roberts M.J.,Hewitt H.T.,et al. Impact of ocean resolution and mean state on the rate of AMOC weakening[J],2020,55.
APA	Jackson L.C..,Roberts M.J..,Hewitt H.T..,Iovino D..,Koenigk T..,...&Wood R.A..(2020).Impact of ocean resolution and mean state on the rate of AMOC weakening.Climate Dynamics,55.
MLA	Jackson L.C.,et al."Impact of ocean resolution and mean state on the rate of AMOC weakening".Climate Dynamics 55(2020).