Rapid reductions and millennial-scale variability in Nordic Seas sea ice cover during abrupt glacial climate changes

Type Article
Date 2020-11
Language English
Author(s) Sadatzki Henrik1, 2, 3, Maffezzoli Niccolò4, 5, 6, Dokken Trond M.2, 7, Simon Margit H2, 7, Berben Sarah M. P.1, 2, Fahl Kirsten3, Kjær Helle A.4, Spolaor Andrea5, 6, Stein Ruediger3, 8, Vallelonga Paul4, 9, Vinther Bo M.4, Jansen Eystein1, 2, 7
Affiliation(s) 1 : Department of Earth Science, University of Bergen, 5007 Bergen, Norway
2 : Bjerknes Centre for Climate Research, 5007 Bergen, Norway
3 : Marine Geology Section, Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, 27568 Bremerhaven, Germany
4 : Centre for Ice and Climate, Niels Bohr Institute, University of Copenhagen, 2100 Copenhagen, Denmark
5 : Department of Environmental Sciences, Informatics and Statistics, Ca’ Foscari University of Venice, 30170 Venice Mestre, Italy
6 : Institute of Polar Science–National Research Council of Italy, (I) 30172 Venezia-Mestre (VE), Italy
7 : Climate, Norwegian Research Centre AS (NORCE), 5007 Bergen, Norway
8 : MARUM Center for Marine Environmental Sciences and Faculty of Geosciences, University of Bremen, 28334 Bremen, Germany
9 : Oceans Institute, The University of Western Australia, Crawley, WA 6009, Australia
Source Proceedings Of The National Academy Of Sciences Of The United States Of America (0027-8424) (Proceedings of the National Academy of Sciences), 2020-11 , Vol. 117 , N. 47 , P. 29478-29486
DOI 10.1073/pnas.2005849117
WOS© Times Cited 1
Keyword(s) sea ice, Nordic Seas, Dansgaard-Oeschger events, abrupt climate change
Abstract

Constraining the past sea ice variability in the Nordic Seas is critical for a comprehensive understanding of the abrupt Dansgaard-Oeschger (D-O) climate changes during the last glacial. Here we present unprecedentedly detailed sea ice proxy evidence from two Norwegian Sea sediment cores and an East Greenland ice core to resolve and constrain sea ice variations during four D-O events between 32 and 41 ka. Our independent sea ice records consistently reveal a millennial-scale variability and threshold response between an extensive seasonal sea ice cover in the Nordic Seas during cold stadials and reduced seasonal sea ice conditions during warmer interstadials. They document substantial and rapid sea ice reductions that may have happened within 250 y or less, concomitant with reinvigoration of deep convection in the Nordic Seas and the abrupt warming transitions in Greenland. Our empirical evidence thus underpins the cardinal role of rapid sea ice decline and related feedbacks to trigger abrupt and large-amplitude climate change of the glacial D-O events.

Full Text
File Pages Size Access
Publisher's official version 9 11 MB Open access
Appendix 12 1 MB Open access
Dataset S01 56 KB Open access
Dataset S02 58 KB Open access
Dataset S03 68 KB Open access
Dataset S04 59 KB Open access
Dataset S05 54 KB Open access
Dataset S06 19 MB Open access
Dataset S07 45 KB Open access
Top of the page

How to cite 

Sadatzki Henrik, Maffezzoli Niccolò, Dokken Trond M., Simon Margit H, Berben Sarah M. P., Fahl Kirsten, Kjær Helle A., Spolaor Andrea, Stein Ruediger, Vallelonga Paul, Vinther Bo M., Jansen Eystein (2020). Rapid reductions and millennial-scale variability in Nordic Seas sea ice cover during abrupt glacial climate changes. Proceedings Of The National Academy Of Sciences Of The United States Of America, 117(47), 29478-29486. Publisher's official version : https://doi.org/10.1073/pnas.2005849117 , Open Access version : https://archimer.ifremer.fr/doc/00659/77066/