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Title: Surface climate signals transmitted rapidly to deep North Atlantic throughout last millennium

Instrumental observations of subsurface ocean warming imply that ocean heat uptake has slowed 20th-century surface warming. We present high-resolution records from subpolar North Atlantic sediments that are consistent with instrumental observations of surface and deep warming/freshening and in addition reconstruct the surface-deep relation of the last 1200 years. Sites from ~1300 meters and deeper suggest an ~0.5 degrees celsius cooling across the Medieval Climate Anomaly to Little Ice Age transition that began ~1350 ± 50 common era (CE), whereas surface records suggest asynchronous cooling onset spanning ~600 years. These data suggest that ocean circulation integrates surface variability that is transmitted rapidly to depth by the Atlantic Meridional Ocean Circulation, implying that the ocean moderated Earth’s surface temperature throughout the last millennium as it does today.

 
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Award ID(s):
2031929
NSF-PAR ID:
10479466
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
AAAS
Date Published:
Journal Name:
Science
Volume:
382
Issue:
6672
ISSN:
0036-8075
Page Range / eLocation ID:
834 to 839
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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