Sea ice variability in the southern Norwegian Sea during glacial Dansgaard-Oeschger climate cycles
|Author(s)||Sadatzki Henrik1, Dokken Trond M.2, Berben Sarah M. P.1, Muschitiello Francesco3, 4, Stein Ruediger5, 6, Fahl Kirsten5, Menviel Laurie7, 8, Timmermann Axel9, 10, Jansen Eystein1, 2|
|Affiliation(s)||1 : Department of Earth Science and Bjerknes Centre for Climate Research, University of Bergen, 5007 Bergen, Norway.
2 : NORCE Norwegian Research Centre, Bjerknes Centre for Climate Research, 5007 Bergen, Norway.
3 : Department of Geography, University of Cambridge, Cambridge CB2 3EQ, UK.
4 : Lamont-Doherty Earth Observatory of Columbia University, 61 Route 9W, P.O. Box 1000, Palisades, NY 10964, USA.
5 : Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, 27568 Bremerhaven, Germany.
6 : MARUM and Faculty of Geosciences (FB 5), University of Bremen, P.O. Box 330440, 28334 Bremen, Germany.
7 : Climate Change Research Centre and PANGEA Research Centre, University of New South Wales, Sydney, New South Wales 2052, Australia.
8 : Department of Earth and Planetary Sciences, Macquarie University, Sydney, New South Wales, Australia.
9 : Center for Climate Physics, Institute for Basic Science (IBS), Busan, South Korea.
10 : Pusan National University, Busan, South Korea.
|Source||Science Advances (2375-2548) (American Association for the Advancement of Science (AAAS)), 2019-03 , Vol. 5 , N. 3 , P. eaau6174 (11p.)|
|WOS© Times Cited||31|
The last glacial period was marked by pronounced millennial-scale variability in ocean circulation and global climate. Shifts in sea ice cover within the Nordic Seas are believed to have amplified the glacial climate variability in northern high latitudes and contributed to abrupt, high-amplitude temperature changes over Greenland. We present unprecedented empirical evidence that resolves the nature, timing, and role of sea ice fluctuations for abrupt ocean and climate change 32 to 40 thousand years ago, using biomarker sea ice reconstructions from the southern Norwegian Sea. Our results document that initial sea ice reductions at the core site preceded the major reinvigoration of convective deep-water formation in the Nordic Seas and abrupt Greenland warming; sea ice expansions preceded the buildup of a deep oceanic heat reservoir. Our findings suggest that the sea ice variability shaped regime shifts between surface stratification and deep convection in the Nordic Seas during abrupt climate changes.