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Title: Annually resolved Atlantic sea surface temperature variability over the past 2,900 y
Global warming due to anthropogenic factors can be amplified or dampened by natural climate oscillations, especially those involving sea surface temperatures (SSTs) in the North Atlantic which vary on a multidecadal scale (Atlantic multidecadal variability, AMV). Be- cause the instrumental record of AMV is short, long-term behavior of AMV is unknown, but climatic teleconnections to regions beyond the North Atlantic offer the prospect of reconstructing AMV from high-resolution records elsewhere. Annually resolved titanium from an annually laminated sedimentary record from Ellesmere Island, Canada, shows that the record is strongly influenced by AMV via atmospheric circulation anomalies. Significant correlations between this High-Arctic proxy and other highly resolved Atlantic SST proxies demonstrate that it shares the multidecadal variability seen in the Atlantic. Our record provides a reconstruction of AMV for the past ∼3 millennia at an unprecedented time resolution, indicating North Atlantic SSTs were coldest from ∼1400–1800 CE, while current SSTs are the warmest in the past ∼2,900 y.
Authors:
Award ID(s):
1744515
Publication Date:
NSF-PAR ID:
10250856
Journal Name:
Proceedings of the National Academy of Sciences of the United States of America
Volume:
117
Issue:
44
Page Range or eLocation-ID:
27171-27178
ISSN:
1091-6490
Sponsoring Org:
National Science Foundation
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