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{{Short description|Current of the Atlantic Ocean}}
{{Redirect|North Atlantic Drift|the 2003 rock album by [[Ocean Colour Scene]]|North Atlantic Drift (album)}}
[[File:North Atlantic currents.svg|thumb|The North Atlantic Current is the first leg in the North Atlantic Subpolar Gyre
The '''North Atlantic Current''' ('''NAC'''), also known as '''North Atlantic Drift''' and '''North Atlantic Sea Movement''', is a powerful warm [[western boundary current]] within the [[Atlantic Ocean]] that extends the [[Gulf Stream]] northeastward.<ref name="Rossby-Abst">{{Harvnb|Rossby|1996|loc=Abstract}}</ref>
== Characteristics ==
The NAC originates from where the Gulf Stream turns north at the Southeast Newfoundland Rise, a submarine ridge that stretches southeast from the [[Grand Banks of Newfoundland]]. The NAC flows northward east of the Grand Banks, from 40°N to 51°N, before turning sharply east to cross the Atlantic. It transports more warm tropical water to northern latitudes than any other boundary current; more than 40 [[Sverdrup|Sv]] ({{Convert|40|e6m3/s|abbr=unit|disp=comma}}) in the south and 20 Sv ({{Convert|20|e6m3/s|abbr=unit|disp=comma}}) as it crosses the [[Mid-Atlantic Ridge]]. It reaches speeds of {{Convert|2|kn}} near the [[North America]]n coast. Directed by topography, the NAC meanders heavily, but in contrast to the meanders of the Gulf Stream, the NAC meanders remain stable without breaking off into eddies.<ref name="Rossby-Abst" />▼
▲The NAC originates from where the Gulf Stream turns north at the Southeast Newfoundland Rise, a submarine ridge that stretches southeast from the [[Grand Banks of Newfoundland]].
The colder parts of the Gulf Stream turn northward near the "tail" of the Grand Banks at 50°W where the [[Azores Current]] branches off to flow south of the [[Azores]].
West of [[Continental Europe]], it splits into two major branches. One branch goes southeast, becoming the [[Canary Current]] as it passes northwest [[Africa]] and turns southwest. The other major branch continues north along the coast of [[Northwestern Europe]].
Other branches include the [[Irminger Current]] and the [[Norwegian Current]]. Driven by the global [[thermohaline circulation]], the North Atlantic Current is part of the wind-driven Gulf Stream, which goes further east and north from the North American coast across the Atlantic and into the [[Arctic Ocean]].
The North Atlantic Current, together with the Gulf Stream, have a long-lived reputation for having a considerable warming influence on European climate.
== Climate change ==
[[File:Sgubin2017 spg amoc collapse.jpg|thumb|Modelled 21st century warming under the [[
{{See also|Tipping points in the climate system}}
Unlike the [[AMOC]], the observations of Labrador Sea outflow showed no negative trend from 1997 to 2009,<ref>{{Cite journal |last1=Fischer |first1=Jürgen |last2=Visbeck |first2=Martin |last3=Zantopp |first3=Rainer |last4=Nunes |first4=Nuno |date=31 December 2010 |title=Interannual to decadal variability of outflow from the Labrador Sea
Some [[climate model]]s indicate that the deep convection in [[Labrador Sea|Labrador]]-[[Irminger Sea|Irminger]] Seas could collapse under certain [[global warming]] scenarios, which would then collapse the entire circulation in the North [[subpolar gyre]]. It is considered unlikely to recover even if the temperature is returned to a lower level, making it an example of a climate tipping point. This would result in rapid cooling, with implications for economic sectors, agriculture industry, water resources and energy management in Western Europe and the East Coast of the United States.<ref>{{cite journal|title=Abrupt cooling over the North Atlantic in modern climate models|journal=Nature Communications|volume=8|doi=10.1038/ncomms14375|pmid=28198383|pmc=5330854|author=Sgubin |display-authors=etal |year=2017 |bibcode=
A 2021 study found that this collapse occurs in only four [[CMIP6]] models out of 35 analyzed. However, only 11 models out of 35 can simulate North Atlantic Current with a high degree of accuracy, and this includes all four models which simulate collapse of the subpolar gyre. As the result, the study estimated the risk of an abrupt cooling event over Europe caused by the collapse of the current at 36.4%, which is lower than the 45.5% chance estimated by the previous generation of models <ref>{{Cite journal |last1=Swingedouw |first1=Didier |last2=Bily |first2=Adrien |last3=Esquerdo |first3=Claire |last4=Borchert |first4=Leonard F. |last5=Sgubin |first5=Giovanni |last6=Mignot |first6=Juliette |last7=Menary |first7=Matthew |date=2021 |title=On the risk of abrupt changes in the North Atlantic subpolar gyre in CMIP6 models |url=https://nyaspubs.onlinelibrary.wiley.com/doi/10.1111/nyas.14659 |journal=Annals of the New York Academy of Sciences |volume=1504 |issue=1 |pages=187–201 |doi=10.1111/nyas.14659|pmid=34212391 |bibcode=2021NYASA1504..187S |s2cid=235712017 |hdl=10447/638022 |hdl-access=free }}</ref> In 2022, a paper suggested that previous disruption of subpolar gyre was connected to the [[Little Ice Age]].<ref>{{Cite journal |last1=Arellano-Nava |first1=Beatriz |last2=Halloran |first2=Paul R. |last3=Boulton |first3=Chris A. |last4=Scourse |first4=James |last5=Butler |first5=Paul G. |last6=Reynolds |first6=David J. |last7=Lenton |first7=Timothy |date=25 August 2022 |title=Destabilisation of the Subpolar North Atlantic prior to the Little Ice Age |journal=Nature Communications |volume=13 |issue=1 |page=5008 |doi=10.1038/s41467-022-32653-x |pmid=36008418 |pmc=9411610 |bibcode=2022NatCo..13.5008A }}</ref>
A 2022 [[Science Magazine]] review study on climate tipping points noted that in the scenarios where this convection collapses, it is most likely to be triggered by 1.8 degrees of global warming. However, model differences mean that the required warming may be as low as 1.1 degrees or as high as 3.8 degrees. Once triggered, the collapse of the current would most likely take 10 years from start to end, with a range between 5 and 50 years. The loss of this convection is estimated to lower the global temperature by up to 0.5 degrees, while the [https://upload.wikimedia.org/wikipedia/commons/thumb/c/cd/Sgubin2017_spg_amoc_collapse.jpg/220px-Sgubin2017_spg_amoc_collapse.jpg average temperature in
A 2023 study warns that the collapse could already happen by mid century.<ref>{{Cite journal |last1=Ditlevsen |first1=Peter|last2=Ditlevsen |first2=Susanne |date=25 July 2023 |title=Warning of a forthcoming collapse of the Atlantic meridional overturning circulation |url=https://www.nature.com/articles/s41467-023-39810-w |journal=Nature |language=en |volume=14 |issue=1 |pages=4254 |doi=10.1038/s41467-023-39810-w |pmid=37491344|arxiv=2304.09160 }}</ref>
== See also ==
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* [[Ocean gyre]]
* [[Physical oceanography]]
{{refs}}
== References ==
▲; Notes
{{refbegin|30em}}
* {{Cite journal|last1=Lozier|first1=M. S.|author-link=Susan Lozier|last2=Owens|first2=W. B.|last3=Curry|first3=R. G.|title=The climatology of the North Atlantic|year=1995|journal=Progress in Oceanography|volume=36|issue=1|pages=1–44|url=http://www.whoi.edu/science/PO/people/rcurry/pdf_files/Lozier_etal.PiO1995.pdf|access-date=19 November 2016|doi=10.1016/0079-6611(95)00013-5|bibcode=1995PrOce..36....1L}}<!-- {{Harvnb|Lozier|Owens|Curry|1995}} -->
* {{Cite journal|last=Rossby|first=T.|title=The North Atlantic Current and surrounding waters: At the crossroads|year=1996|journal=Reviews of Geophysics|volume=34|issue=4|pages=463–481|url=http://climate.fas.harvard.edu/files/climate/files/rossby96rg.pdf|access-date=19 November 2016|doi=10.1029/96RG02214|bibcode=1996RvGeo..34..463R}}<!-- {{Harvnb|Rossby|1996}} -->
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== External links ==
* [http://oceancurrents.rsmas.miami.edu/atlantic/north-atlantic.html "The North Atlantic Current"]. Elizabeth Rowe, Arthur J. Mariano, Edward H. Ryan, [[Cooperative Institute for Marine and Atmospheric Studies]]
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[[Category:Currents of the Atlantic Ocean]]
[[Category:Barents Sea]]
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