Gray, WR, Wills, RCJ, Rae, JWB et al. (5 more authors) (2020) Wind‐Driven Evolution of the North Pacific Subpolar Gyre Over the Last Deglaciation. Geophysical Research Letters, 47 (6). e2019GL086328. ISSN 0094-8276
Abstract
North Pacific atmospheric and oceanic circulations are key missing pieces in our understanding of the reorganization of the global climate system since the Last Glacial Maximum. Here, using a basin‐wide compilation of planktic foraminiferal δ18O, we show that the North Pacific subpolar gyre extended ~3° further south during the Last Glacial Maximum, consistent with sea surface temperature and productivity proxy data. Climate models indicate that the expansion of the subpolar gyre was associated with a substantial gyre strengthening, and that these gyre circulation changes were driven by a southward shift of the midlatitude westerlies and increased wind stress from the polar easterlies. Using single‐forcing model runs, we show that these atmospheric circulation changes are a nonlinear response to ice sheet topography/albedo and CO2. Our reconstruction indicates that the gyre boundary (and thus westerly winds) began to migrate northward at ~16.5 ka, driving changes in ocean heat transport, biogeochemistry, and North American hydroclimate.
Metadata
Authors/Creators: |
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Copyright, Publisher and Additional Information: | © 2020, American Geophysical Union. All Rights Reserved. Reproduced in accordance with the publisher's self-archiving policy. | ||||||
Keywords: | North Pacific; deglaciation; gyre circulation; westerlies; oxygen isotopes; climate models | ||||||
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Institution: | The University of Leeds | ||||||
Academic Units: | The University of Leeds > Faculty of Environment (Leeds) > School of Earth and Environment (Leeds) > Inst for Climate & Atmos Science (ICAS) (Leeds) | ||||||
Funding Information: |
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Depositing User: | Symplectic Publications | ||||||
Date Deposited: | 10 Mar 2020 11:40 | ||||||
Last Modified: | 26 Aug 2020 00:38 | ||||||
Status: | Published | ||||||
Publisher: | American Geophysical Union | ||||||
Identification Number: | https://doi.org/10.1029/2019gl086328 |