Early Last Interglacial ocean warming drove substantial ice mass loss from Antarctica.

Autor:	Turney CSM; Palaeontology, Geobiology and Earth Archives Research Centre, School of Biological, Earth and Environmental Sciences, University of New South Wales, Kensington NSW 2033, Australia; c.turney@unsw.edu.au.; Australian Research Council Centre of Excellence in Australian Biodiversity and Heritage, School of Biological, Earth and Environmental Sciences, University of New South Wales, Kensington NSW 2033, Australia.; Chronos Carbon-Cycle Facility, University of New South Wales, Sydney NSW 2052, Australia., Fogwill CJ; Palaeontology, Geobiology and Earth Archives Research Centre, School of Biological, Earth and Environmental Sciences, University of New South Wales, Kensington NSW 2033, Australia.; School of Geography, Geology and the Environment, Keele University, Staffordshire ST5 5BG, United Kingdom., Golledge NR; Antarctic Research Centre, Victoria University of Wellington, Wellington 6140, New Zealand.; Environment and Climate, GNS Science, Avalon, Lower Hutt 5011, New Zealand., McKay NP; School of Earth and Sustainability, Northern Arizona University, Flagstaff, AZ 86011., van Sebille E; Grantham Institute, Imperial College London, London SW7 2AZ, United Kingdom.; Department of Physics, Imperial College London, London SW7 2AZ, United Kingdom.; Institute for Marine and Atmospheric Research Utrecht, Utrecht University, 3584 CS Utrecht, The Netherlands., Jones RT; Department of Geography, Exeter University, Devon EX4 4RJ, United Kingdom., Etheridge D; Climate Science Centre, Commonwealth Scientific and Industrial Research Organisation Ocean and Atmosphere, Aspendale, VIC 3195 Australia., Rubino M; School of Geography, Geology and the Environment, Keele University, Staffordshire ST5 5BG, United Kingdom.; Climate Science Centre, Commonwealth Scientific and Industrial Research Organisation Ocean and Atmosphere, Aspendale, VIC 3195 Australia.; Dipartimento di Matematica e Fisica, Università della Campania 'Luigi Vanvitelli,' 81100 Caserta, Italy., Thornton DP; Climate Science Centre, Commonwealth Scientific and Industrial Research Organisation Ocean and Atmosphere, Aspendale, VIC 3195 Australia., Davies SM; Department of Geography, Swansea University, Swansea SA2 8PP, United Kingdom., Ramsey CB; Research Laboratory for Archaeology and the History of Art, University of Oxford, Oxford OX1 3TG, United Kingdom., Thomas ZA; Palaeontology, Geobiology and Earth Archives Research Centre, School of Biological, Earth and Environmental Sciences, University of New South Wales, Kensington NSW 2033, Australia.; Australian Research Council Centre of Excellence in Australian Biodiversity and Heritage, School of Biological, Earth and Environmental Sciences, University of New South Wales, Kensington NSW 2033, Australia.; Chronos Carbon-Cycle Facility, University of New South Wales, Sydney NSW 2052, Australia., Bird MI; Centre for Tropical Environmental and Sustainability Science, College of Science and Engineering, James Cook University, Cairns, QLD 4870, Australia.; Australian Research Council Centre of Excellence in Australian Biodiversity and Heritage, James Cook University, Cairns, QLD 4870, Australia., Munksgaard NC; Australian Research Council Centre of Excellence in Australian Biodiversity and Heritage, James Cook University, Cairns, QLD 4870, Australia.; Research Institute for the Environment and Livelihoods, Charles Darwin University, Darwin NT 0909, Australia., Kohno M; Department of Geochemistry, Geoscience Center, University of Göttingen, 37077 Göttingen, Germany., Woodward J; Department of Geography and Environmental Sciences, Faculty of Engineering and Environment, Northumbria University, Newcastle upon Tyne NE1 8ST, United Kingdom., Winter K; Department of Geography and Environmental Sciences, Faculty of Engineering and Environment, Northumbria University, Newcastle upon Tyne NE1 8ST, United Kingdom., Weyrich LS; Australian Centre for Ancient DNA, University of Adelaide, Adelaide SA 5005, Australia.; Australian Research Council Centre of Excellence in Australian Biodiversity and Heritage, University of Adelaide, Adelaide SA 5005, Australia., Rootes CM; Department of Geography, University of Sheffield, Sheffield S3 7ND, United Kingdom., Millman H; Palaeontology, Geobiology and Earth Archives Research Centre, School of Biological, Earth and Environmental Sciences, University of New South Wales, Kensington NSW 2033, Australia., Albert PG; Research Laboratory for Archaeology and the History of Art, University of Oxford, Oxford OX1 3TG, United Kingdom., Rivera A; Departamento de Geografia, Universidad de Chile, 8331051 Santiago, Chile., van Ommen T; Department of the Environment and Energy, Australian Antarctic Division, Kingston, TAS 7050, Australia.; Antarctic Climate and Ecosystems Cooperative Research Centre, University of Tasmania, Hobart, TAS 7001, Australia., Curran M; Department of the Environment and Energy, Australian Antarctic Division, Kingston, TAS 7050, Australia.; Antarctic Climate and Ecosystems Cooperative Research Centre, University of Tasmania, Hobart, TAS 7001, Australia., Moy A; Department of the Environment and Energy, Australian Antarctic Division, Kingston, TAS 7050, Australia.; Antarctic Climate and Ecosystems Cooperative Research Centre, University of Tasmania, Hobart, TAS 7001, Australia., Rahmstorf S; Earth System Analysis, Potsdam Institute for Climate Impact Research, D-14412 Potsdam, Germany.; Institute of Physics and Astronomy, University of Potsdam, 14476 Potsdam, Germany., Kawamura K; Research Organizations of Information and Systems, National Institute of Polar Research, Tachikawa, Tokyo 190-8518, Japan.; Department of Polar Science, Graduate University for Advanced Studies, Tachikawa, Tokyo 190-8518, Japan.; Institute of Biogeosciences, Japan Agency for Marine-Earth Science and Technology, Yokosuka 237-0061, Japan., Hillenbrand CD; Palaeo Environments, Ice Sheets and Climate Change, British Antarctic Survey, Cambridge CB3 0ET, United Kingdom., Weber ME; Steinmann Institute, University of Bonn, 53115 Bonn, Germany., Manning CJ; Department of Earth Sciences, Royal Holloway University of London, Surrey TW20 OEX, United Kingdom., Young J; Australian Centre for Ancient DNA, University of Adelaide, Adelaide SA 5005, Australia.; Australian Research Council Centre of Excellence in Australian Biodiversity and Heritage, University of Adelaide, Adelaide SA 5005, Australia., Cooper A; South Australian Museum, Adelaide, South Australia 5005, Australia.
Jazyk:	angličtina
Zdroj:	Proceedings of the National Academy of Sciences of the United States of America [Proc Natl Acad Sci U S A] 2020 Feb 25; Vol. 117 (8), pp. 3996-4006. Date of Electronic Publication: 2020 Feb 11.
DOI:	10.1073/pnas.1902469117
Abstrakt:	The future response of the Antarctic ice sheet to rising temperatures remains highly uncertain. A useful period for assessing the sensitivity of Antarctica to warming is the Last Interglacial (LIG) (129 to 116 ky), which experienced warmer polar temperatures and higher global mean sea level (GMSL) (+6 to 9 m) relative to present day. LIG sea level cannot be fully explained by Greenland Ice Sheet melt (∼2 m), ocean thermal expansion, and melting mountain glaciers (∼1 m), suggesting substantial Antarctic mass loss was initiated by warming of Southern Ocean waters, resulting from a weakening Atlantic meridional overturning circulation in response to North Atlantic surface freshening. Here, we report a blue-ice record of ice sheet and environmental change from the Weddell Sea Embayment at the periphery of the marine-based West Antarctic Ice Sheet (WAIS), which is underlain by major methane hydrate reserves. Constrained by a widespread volcanic horizon and supported by ancient microbial DNA analyses, we provide evidence for substantial mass loss across the Weddell Sea Embayment during the LIG, most likely driven by ocean warming and associated with destabilization of subglacial hydrates. Ice sheet modeling supports this interpretation and suggests that millennial-scale warming of the Southern Ocean could have triggered a multimeter rise in global sea levels. Our data indicate that Antarctica is highly vulnerable to projected increases in ocean temperatures and may drive ice-climate feedbacks that further amplify warming. Competing Interests: The authors declare no competing interest. (Copyright © 2020 the Author(s). Published by PNAS.)
Databáze:	MEDLINE
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