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Title: Climate impacts of a weakened Atlantic Meridional Overturning Circulation in a warming climate
While the Atlantic Meridional Overturning Circulation (AMOC) is projected to slow down under anthropogenic warming, the exact role of the AMOC in future climate change has not been fully quantified. Here, we present a method to stabilize the AMOC intensity in anthropogenic warming experiments by removing fresh water from the subpolar North Atlantic. This method enables us to isolate the AMOC climatic impacts in experiments with a full-physics climate model. Our results show that a weakened AMOC can explain ocean cooling south of Greenland that resembles the North Atlantic warming hole and a reduced Arctic sea ice loss in all seasons with a delay of about 6 years in the emergence of an ice-free Arctic in boreal summer. In the troposphere, a weakened AMOC causes an anomalous cooling band stretching from the lower levels in high latitudes to the upper levels in the tropics and displaces the Northern Hemisphere midlatitude jets poleward.  more » « less
Award ID(s):
1637450 1756682 1741841
PAR ID:
10195845
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
Science Advances
Volume:
6
Issue:
26
ISSN:
2375-2548
Page Range / eLocation ID:
eaaz4876
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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