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Fogwill CJ, Turney CSM, Golledge NR, Etheridge DM, Rubino M, Thornton DP, Baker A, Woodward J, Winter K, van Ommen TD, Moy AD, Curran MAJ, Davies SM, Weber ME, Bird MI, Munksgaard NC, Menviel L, Rootes CM, Ellis B, Millman H, Vohra J, Rivera A, Cooper A. Antarctic ice sheet discharge driven by atmosphere-ocean feedbacks at the Last Glacial Termination. Sci Rep 2017; 7:39979. [PMID: 28054598 PMCID: PMC5215443 DOI: 10.1038/srep39979] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2016] [Accepted: 11/29/2016] [Indexed: 11/17/2022] Open
Abstract
Reconstructing the dynamic response of the Antarctic ice sheets to warming during the Last Glacial Termination (LGT; 18,000–11,650 yrs ago) allows us to disentangle ice-climate feedbacks that are key to improving future projections. Whilst the sequence of events during this period is reasonably well-known, relatively poor chronological control has precluded precise alignment of ice, atmospheric and marine records, making it difficult to assess relationships between Antarctic ice-sheet (AIS) dynamics, climate change and sea level. Here we present results from a highly-resolved ‘horizontal ice core’ from the Weddell Sea Embayment, which records millennial-scale AIS dynamics across this extensive region. Counterintuitively, we find AIS mass-loss across the full duration of the Antarctic Cold Reversal (ACR; 14,600–12,700 yrs ago), with stabilisation during the subsequent millennia of atmospheric warming. Earth-system and ice-sheet modelling suggests these contrasting trends were likely Antarctic-wide, sustained by feedbacks amplified by the delivery of Circumpolar Deep Water onto the continental shelf. Given the anti-phase relationship between inter-hemispheric climate trends across the LGT our findings demonstrate that Southern Ocean-AIS feedbacks were controlled by global atmospheric teleconnections. With increasing stratification of the Southern Ocean and intensification of mid-latitude westerly winds today, such teleconnections could amplify AIS mass loss and accelerate global sea-level rise.
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Affiliation(s)
- C J Fogwill
- PANGEA Research Centre, University of New South Wales, 2052, Australia.,Climate Change Research Centre, School of Biological Earth and Environmental Sciences, University of New South Wales, 2052, Australia
| | - C S M Turney
- PANGEA Research Centre, University of New South Wales, 2052, Australia.,Climate Change Research Centre, School of Biological Earth and Environmental Sciences, University of New South Wales, 2052, Australia
| | - N R Golledge
- Antarctic Research Centre, Victoria University of Wellington, Wellington 6140, New Zealand.,GNS Science, Avalon, Lower Hutt, New Zealand
| | - D M Etheridge
- CSIRO Climate Science Centre, Oceans and Atmosphere, Aspendale, Victoria, 3195 Australia
| | - M Rubino
- CSIRO Climate Science Centre, Oceans and Atmosphere, Aspendale, Victoria, 3195 Australia.,Dipartimento di Matematica e Fisica, Università della Campania - Luigi Vanvitelli, viale Lincoln, 5-81100 Caserta, Italy
| | - D P Thornton
- CSIRO Climate Science Centre, Oceans and Atmosphere, Aspendale, Victoria, 3195 Australia
| | - A Baker
- PANGEA Research Centre, University of New South Wales, 2052, Australia
| | - J Woodward
- Department of Geography, Faculty of Engineering and Environment, Northumbria University, Newcastle upon Tyne, NE1 8ST, United Kingdom
| | - K Winter
- Department of Geography, Faculty of Engineering and Environment, Northumbria University, Newcastle upon Tyne, NE1 8ST, United Kingdom
| | - T D van Ommen
- Australian Antarctic Division, 203 Channel Highway, Kingston, Tasmania 7050, Australia.,Antarctic Climate &Ecosystems Cooperative Research Centre, University of Tasmania, Private Bag 80, Hobart, Tasmania 7001, Australia
| | - A D Moy
- Australian Antarctic Division, 203 Channel Highway, Kingston, Tasmania 7050, Australia.,Antarctic Climate &Ecosystems Cooperative Research Centre, University of Tasmania, Private Bag 80, Hobart, Tasmania 7001, Australia
| | - M A J Curran
- Australian Antarctic Division, 203 Channel Highway, Kingston, Tasmania 7050, Australia.,Antarctic Climate &Ecosystems Cooperative Research Centre, University of Tasmania, Private Bag 80, Hobart, Tasmania 7001, Australia
| | - S M Davies
- Department of Geography, College of Science, Swansea University, Swansea, United Kingdom
| | - M E Weber
- Department of Earth Sciences, University of Cambridge, Drummond Street, Cambridge, United Kingdom.,Steinmann Institute, University of Bonn, Poppelsdorfer Schloss, Bonn, Germany
| | - M I Bird
- Centre for Tropical Environmental and Sustainability Science, College of Science and Engineering, James Cook University, Cairns, Australia
| | - N C Munksgaard
- Centre for Tropical Environmental and Sustainability Science, College of Science and Engineering, James Cook University, Cairns, Australia.,Research Institute for the Environment and Livelihoods, Charles Darwin University, Australia
| | - L Menviel
- PANGEA Research Centre, University of New South Wales, 2052, Australia.,Climate Change Research Centre, School of Biological Earth and Environmental Sciences, University of New South Wales, 2052, Australia
| | - C M Rootes
- Department of Geography, University of Sheffield, United Kingdom
| | - B Ellis
- Research School of Earth Sciences, Australian National University, Canberra, Australia
| | - H Millman
- Climate Change Research Centre, School of Biological Earth and Environmental Sciences, University of New South Wales, 2052, Australia
| | - J Vohra
- PANGEA Research Centre, University of New South Wales, 2052, Australia.,Climate Change Research Centre, School of Biological Earth and Environmental Sciences, University of New South Wales, 2052, Australia
| | - A Rivera
- Glaciology and Climate Change Laboratory, Centro de Estudios Cientficos, Valdivia, Arturo Prat 514, Chile.,Department of Geography, University of Chile, Santiago, Chile
| | - A Cooper
- Australian Centre for Ancient DNA, University of Adelaide, 5005, Australia
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