Glaciología

Glaciares de Chile

Antártica

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

Turney, C., C. Fogwill, N. Golledge, N. McKay, E. Sebille, R. Jones, D. Etheridge, M. Rubino, D. Thornton, S. Davies, C. Bronk, Z. Thomas, M. Bird, N. Munksgaard, M. Kohno, J. Woodward, K. Winter, L. Weyrich, C. Rootes, H. Millman, P. Albert, A. Rivera, T. van Ommen, M. Curran, A. Moy, S. Rahmstorf, K. Kawamura, C. Hillenbrand, M. Weber, C. Manning, J. Young & A. Cooper (2020): “Early Last Interglacial ocean warming drove substantial ice mass loss from Antarctica”. Proceedings of the National Academy of Sciences, 201902469; DOI: 10.1073/pnas.1902469117.

Resumen / Abstract.

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 theWeddell Sea Embayment at the periphery of the marine-based West Antarctic Ice Sheet (WAIS), which is underlain by majormethane hydrate reserves. 



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