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[[File:Sgubin2017 spg amoc collapse.jpg|thumb|Modelled 21st century warming under the [[Representative Concentration Pathway#RCP 4.5|"intermediate" climate change scenario]] (top). The potential collapse of the subpolar gyre in this scenario (middle). The collapse of the entire AMOC (bottom).]]
{{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 |url=https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2010GL045321 |journal=Geophysical Research Letters |volume=37 |issue=24 |pages=3204–3210 |doi=10.1029/2010GL045321 |bibcode=2010GeoRL..3724610F |s2cid=54768522 |access-date=3 October 2022}}</ref> and the Labrador Sea convection began to intensify in 2012, reaching a new high in 2016.<ref>{{Cite journal |last1=Yashayaev |first1=Igor |last2=Loder |first2=John W. |date=8 December 2016 |title=Further intensification of deep convection in the Labrador Sea in 2016 |url=https://agupubs.onlinelibrary.wiley.com/doi/10.1002/2016GL071668 |journal=Geophysical Research Letters |volume=44 |issue=3 |pages=1429–1438 |doi=10.1002/2016GL071668 |s2cid=133577687 |access-date=3 October 2022|doi-access=free }}</ref> As of 2022, the trend of strengthened Labrador Sea convection appears to hold, and is associated with observed increases in [[marine primary production]].<ref>{{Cite journal |last1=Tesdal |first1=Jan-Erik |last2=Ducklow |first2=Hugh W. |last3=Goes |first3=Joaquim I. |last4=Yashayaev |first4=Igor |date=August 2022 |title=Recent nutrient enrichment and high biological productivity in the Labrador Sea is tied to enhanced winter convection |url=https://www.sciencedirect.com/science/article/abs/pii/S0079661122001069 |journal=Geophysical Research Letters |volume=44 |issue=3 |page=102848 |doi=10.1016/j.pocean.2022.102848 |bibcode=2022PrOce.20602848T |s2cid=249977465 |access-date=3 October 2022|doi-access=free }}</ref> Yet, a 150-year dataset suggests that even this recently strengthened convection is anomalously weak compared to its baseline state.<ref>{{Cite journal |last1=Thornalley |first1=David JR |display-authors=etal |date=11 April 2018 |title=Anomalously weak Labrador Sea convection and Atlantic overturning during the past 150 years |url=https://www.nature.com/articles/s41586-018-0007-4 |journal=Nature |volume=556 |issue=7700 |pages=227–230 |doi=10.1038/s41586-018-0007-4 |pmid=29643484 |bibcode=2018Natur.556..227T |s2cid=4771341 |access-date=3 October 2022}}</ref>
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=2017NatCo...8.....S}}</ref> Frajka-Williams et al. 2017 pointed out that recent changes in cooling of the subpolar gyre, warm temperatures in the subtropics and cool anomalies over the tropics, increased the spatial distribution of meridional gradient in sea surface temperatures, which is not captured by the [[AMO Index]].<ref name="Frajka-Williams">{{cite journal|doi=10.1038/s41598-017-11046-x|pmid=28894211|pmc=5593924|author=Eleanor Frajka-Williams |author2=Claudie Beaulieu |author3=Aurelie Duchez|title=Emerging negative Atlantic Multidecadal Oscillation index in spite of warm subtropics|journal=Scientific Reports|volume=7|issue=1|pages=11224|year=2017|bibcode=2017NatSR...711224F}}</ref>
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