Antarctic ice sheet discharge driven by atmosphere-ocean feedbacks at the Last Glacial Termination.

Autor: Fogwill CJ; 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., Turney CS; 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., Golledge NR; Antarctic Research Centre, Victoria University of Wellington, Wellington 6140, New Zealand.; GNS Science, Avalon, Lower Hutt, New Zealand., Etheridge DM; CSIRO Climate Science Centre, Oceans and Atmosphere, Aspendale, Victoria, 3195 Australia., Rubino M; 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., Thornton DP; CSIRO Climate Science Centre, Oceans and Atmosphere, Aspendale, Victoria, 3195 Australia., Baker A; PANGEA Research Centre, University of New South Wales, 2052, Australia., Woodward J; Department of Geography, Faculty of Engineering and Environment, Northumbria University, Newcastle upon Tyne, NE1 8ST, United Kingdom., Winter K; Department of Geography, Faculty of Engineering and Environment, Northumbria University, Newcastle upon Tyne, NE1 8ST, United Kingdom., van Ommen TD; 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., Moy AD; 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., Curran MA; 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., Davies SM; Department of Geography, College of Science, Swansea University, Swansea, United Kingdom., Weber ME; Department of Earth Sciences, University of Cambridge, Drummond Street, Cambridge, United Kingdom.; Steinmann Institute, University of Bonn, Poppelsdorfer Schloss, Bonn, Germany., Bird MI; Centre for Tropical Environmental and Sustainability Science, College of Science and Engineering, James Cook University, Cairns, Australia., Munksgaard NC; 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., Menviel L; 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., Rootes CM; Department of Geography, University of Sheffield, United Kingdom., Ellis B; Research School of Earth Sciences, Australian National University, Canberra, Australia., Millman H; Climate Change Research Centre, School of Biological Earth and Environmental Sciences, University of New South Wales, 2052, Australia., Vohra J; 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., Rivera A; Glaciology and Climate Change Laboratory, Centro de Estudios Cientficos, Valdivia, Arturo Prat 514, Chile.; Department of Geography, University of Chile, Santiago, Chile., Cooper A; Australian Centre for Ancient DNA, University of Adelaide, 5005, Australia.
Jazyk: angličtina
Zdroj: Scientific reports [Sci Rep] 2017 Jan 05; Vol. 7, pp. 39979. Date of Electronic Publication: 2017 Jan 05.
DOI: 10.1038/srep39979
Abstrakt: 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.
Databáze: MEDLINE