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Title: A sea change in our view of overturning in the subpolar North Atlantic
To provide an observational basis for the Intergovernmental Panel on Climate Change projections of a slowing Atlantic meridional overturning circulation (MOC) in the 21st century, the Overturning in the Subpolar North Atlantic Program (OSNAP) observing system was launched in the summer of 2014. The first 21-month record reveals a highly variable overturning circulation responsible for the majority of the heat and freshwater transport across the OSNAP line. In a departure from the prevailing view that changes in deep water formation in the Labrador Sea dominate MOC variability, these results suggest that the conversion of warm, salty, shallow Atlantic waters into colder, fresher, deep waters that move southward in the Irminger and Iceland basins is largely responsible for overturning and its variability in the subpolar basin.
Authors:
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Award ID(s):
1756223 1756143 1756231 1259398 1634886
Publication Date:
NSF-PAR ID:
10086286
Journal Name:
Science
Volume:
363
Issue:
6426
Page Range or eLocation-ID:
516 to 521
ISSN:
0036-8075
Sponsoring Org:
National Science Foundation
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