Antarctic ice sheet discharge driven by atmosphere-ocean feedbacks at the Last Glacial Termination
Fogwill, C.J.; Turney, C.S.M.; Golledge, N.R.; Etheridge, D.M.; Rubino, M.; Thornton, D.P.; Baker, A.; Woodward, J.; Winter, K.; van Ommen, T.D.; Moy, A.D.; Curran, M.A.J.; Davies, S.M.; Weber, M.E.; Bird, M.I.; Munksgaard, N.C.; Menviel, L.; Rootes, C.M.; Ellis, E.; Millman, H.; Vohra, J.; Rivera, A.; Cooper, A. (2017). Antarctic ice sheet discharge driven by atmosphere-ocean feedbacks at the Last Glacial Termination. NPG Scientific Reports 7(39979): 10 pp. http://dx.doi.org/10.1038/srep39979
In: Scientific Reports (Nature Publishing Group). Nature Publishing Group: London. ISSN 2045-2322; e-ISSN 2045-2322, more
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| Authors | | Top |
- Fogwill, C.J.
- Turney, C.S.M.
- Golledge, N.R.
- Etheridge, D.M.
- Rubino, M.
- Thornton, D.P.
- Baker, A.
- Woodward, J.
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- Winter, K.
- van Ommen, T.D.
- Moy, A.D.
- Curran, M.A.J.
- Davies, S.M.
- Weber, M.E.
- Bird, M.I.
- Munksgaard, N.C.
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- Menviel, L.
- Rootes, C.M.
- Ellis, E.
- Millman, H.
- Vohra, J.
- Rivera, A.
- Cooper, A.
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| 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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