Obliquity-paced Pliocene West Antarctic ice sheet oscillations

• Published in: Nature
• Main Authors: Naish, T., Powell, R., Levy, R., Wilson, G., Scherer, R., Talarico, F., Krissek, L., Niessen, F., Pompilio, M., Wilson, T., Carter, L., DeConto, R., Huybers, P., Mckay, R., Pollard, D., Ross, J., Winter, D., Barrett, P., Browne, G., Cody, R., Cowan, E., Crampton, J., Dunbar, G., Florindo, F., Gebhardt, C., Graham, I., Hannah, M., Hansaraj, D., Harwood, D., Helling, D., Henrys, S., Hinnov, L., Kuhn, G., Kyle, P., Laüfer, A., Maffioli, P., Magens, D., Mandernack, K., McIntosh, W., Millan, C., Morin, R., Ohneiser, C., Paulsen, T., Persico, D., Raine, I., Reed, J., Riesselman, C., Sagnotti, L., Schmitt, D., Sjunneskog, C.
• Other Authors: Naish, T.; Antarctic Research Centre, Victoria University of Wellington, Kelburn Parade, PO Box 600, Wellington 6012, New Zealand, Powell, R.; Department of Geology & Environmental Geosciences, Northern Illinois University, DeKalb, Illinois 60115, USA., Levy, R.; ANDRILL Science Management Office, Department of Geosciences, University of Nebraska-Lincoln, Lincoln, Nebraska 68588-0340, USA, Wilson, G.; University of Otago, Department of Geology, PO Box 56, Leith Street, Dunedin, Otago 9001, New Zealand, Scherer, R.; Department of Geology & Environmental Geosciences, Northern Illinois University, DeKalb, Illinois 60115, USA., Talarico, F.; Universita` di Siena, Dipartimento di Scienze delle Terra, Via Laterina 8, I-53100 Siena, Italy, Krissek, L.; Ohio State University, Department of Geological Sciences, 275 Mendenhall Lab, 125 South Oval Mall, Columbus, Ohio 43210, USA, Niessen, F.; Alfred Wegener Institute, Department of Geosciences, Postfach 12 01 6, Am Alten Hafen 26, D-27515 Bremerhaven, Germany, Pompilio, M.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Pisa, Pisa, Italia, Wilson, T.; Ohio State University, Department of Geological Sciences, 275 Mendenhall Lab, 125 South Oval Mall, Columbus, Ohio 43210, USA, Carter, L.; Antarctic Research Centre, Victoria University of Wellington, Kelburn Parade, PO Box 600, Wellington 6012, New Zealand, DeConto, R.; Department of Geosciences, 233 Morrell Science Centre, University of Massachusetts, Amherst, Massachusetts 01003-9297, USA, Huybers, P.; Department of Earth and Planetary Sciences, Harvard University, Massachusetts 02138, USA, Mckay, R.; Antarctic Research Centre, Victoria University of Wellington, Kelburn Parade, PO Box 600, Wellington 6012, New Zealand, Pollard, D.; Earth and Environmental Systems Institute, Pennsylvania State University, University Park, Pennsylvania 16802, USA, Ross, J.; New Mexico Institute of Mining & Technology, Earth & Environmental Sciences, Socorro, New Mexico 87801, USA, Winter, D.; ANDRILL Science Management Office, Department of Geosciences, University of Nebraska-Lincoln, Lincoln, Nebraska 68588-0340, USA, Barrett, P.; Antarctic Research Centre, Victoria University of Wellington, Kelburn Parade, PO Box 600, Wellington 6012, New Zealand, Browne, G.; GNS Science, 1 Fairway Drive, PO Box 30-368, Lower Hutt 5040, New Zealand, Cody, R.; Antarctic Research Centre, Victoria University of Wellington, Kelburn Parade, PO Box 600, Wellington 6012, New Zealand, Cowan, E.; Department of Geology, Appalachian State University, ASU Box 32067, Boone, North Carolina 28608-2067, USA, Crampton, J.; GNS Science, 1 Fairway Drive, PO Box 30-368, Lower Hutt 5040, New Zealand, Dunbar, G.; Antarctic Research Centre, Victoria University of Wellington, Kelburn Parade, PO Box 600, Wellington 6012, New Zealand, Florindo, F.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia, Gebhardt, C.; Alfred Wegener Institute, Department of Geosciences, Postfach 12 01 6, Am Alten Hafen 26, D-27515 Bremerhaven, Germany, Graham, I.; GNS Science, 1 Fairway Drive, PO Box 30-368, Lower Hutt 5040, New Zealand, Hannah, M.; Antarctic Research Centre, Victoria University of Wellington, Kelburn Parade, PO Box 600, Wellington 6012, New Zealand, Hansaraj, D.; Antarctic Research Centre, Victoria University of Wellington, Kelburn Parade, PO Box 600, Wellington 6012, New Zealand, Harwood, D.; ANDRILL Science Management Office, Department of Geosciences, University of Nebraska-Lincoln, Lincoln, Nebraska 68588-0340, USA, Helling, D.; Alfred Wegener Institute, Department of Geosciences, Postfach 12 01 6, Am Alten Hafen 26, D-27515 Bremerhaven, Germany, Henrys, S.; GNS Science, 1 Fairway Drive, PO Box 30-368, Lower Hutt 5040, New Zealand, Hinnov, L.; Department of Earth and Planetary Sciences, Johns Hopkins University, Baltimore, Maryland 21218, USA, Kuhn, G.; Alfred Wegener Institute, Department of Geosciences, Postfach 12 01 6, Am Alten Hafen 26, D-27515 Bremerhaven, Germany, Kyle, P.; New Mexico Institute of Mining & Technology, Earth & Environmental Sciences, Socorro, New Mexico 87801, USA, Laüfer, A.; Federal Institute of Geosciences & Natural Resources, BGR, Stilleweg 2, D-30655 Hannover, Germany, Maffioli, P.; Universita` Milano-Bicocca, Dipartimento di Scienze Geologiche e Geotecnologie, Piazza della Scienza 4, I-20126 Milano, Italy, Magens, D.; Alfred Wegener Institute, Department of Geosciences, Postfach 12 01 6, Am Alten Hafen 26, D-27515 Bremerhaven, Germany, Mandernack, K.; Colorado School of Mines, Department of Chemistry & Geochemistry, 1500 Illinois Street, Golden, Colorado 80401, USA, McIntosh, W.; New Mexico Institute of Mining & Technology, Earth & Environmental Sciences, Socorro, New Mexico 87801, USA, Millan, C.; Ohio State University, Department of Geological Sciences, 275 Mendenhall Lab, 125 South Oval Mall, Columbus, Ohio 43210, USA, Morin, R.; US Geological Survey, Mail Stop 403, Denver Federal Center, Denver, Colorado 80225, USA, Ohneiser, C.; University of Otago, Department of Geology, PO Box 56, Leith Street, Dunedin, Otago 9001, New Zealand, Paulsen, T.; University of Wisconsin-Oshkosh, Department of Geology, 800 Algoma Boulevard, Oshkosh, Wisconsin 54901, USA, Persico, D.; Dipartimento di Scienze della Terra, Universita` degli Studi di Parma, Via Usberti 157/A, I-43100 Parma, Italy, Raine, I.; GNS Science, 1 Fairway Drive, PO Box 30-368, Lower Hutt 5040, New Zealand, Reed, J.; CHRONOS, Iowa State University, Department of Geological & Atmospheric Sciences, 275 Science I, Ames, Iowa 50011-3212, USA, Riesselman, C.; Department of Geological and Environmental Sciences, School of Earth Sciences, Stanford University, Stanford, California 94305, USA, Sagnotti, L.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia, Schmitt, D.; Department of Physics, Mailstop #615, University of Alberta, Edmonton, Alberta T6G 2G7, Canada, Sjunneskog, C.; Department of Geology and Geophysics, Louisiana State University, Baton Rouge, Louisiana 70803, USA
• Format: Article in Journal/Newspaper
• Language: English
• Published: Macmillan 2009
• Subjects: Antarctica; paleoclimate; Pliocene; stratigraphy; 02. Cryosphere::02.02. Glaciers::02.02.99. General or miscellaneous; 03. Hydrosphere::03.01. General::03.01.06. Paleoceanography and paleoclimatology; 04. Solid Earth::04.04. Geology::04.04.10. Stratigraphy; Antarctic; The Antarctic; West Antarctic Ice Sheet; Ross Ice Shelf; Antarc*; Ice Sheet; Ice Shelf; Ice Shelves; Sea ice
• Online Access: http://hdl.handle.net/2122/5120; https://doi.org/10.1038/nature07867

Thirty years after oxygen isotope records frommicrofossils deposited in ocean sediments confirmed the hypothesis that variations in the Earth’s orbital geometry control the ice ages1, fundamental questions remain over the response of the Antarctic ice sheets to orbital cycles2. Furthermore, an understanding of the behaviour of the marine-based West Antarctic ice sheet (WAIS) during the ‘warmer-than- present’ early-Pliocene epoch (̃5–3Myr ago) is needed to better constrain the possible range of ice-sheet behaviour in the context of future global warming3. Here we present a marine glacial record from the upper 600 m of theAND-1B sediment core recovered from beneath the northwest part of the Ross ice shelf by the ANDRILL programme and demonstrate well-dated, ̃40-kyr cyclic variations in ice-sheet extent linked to cycles in insolation influenced by changes in the Earth’s axial tilt (obliquity) during the Pliocene. Our data provide direct evidence for orbitally induced oscillations in the WAIS, which periodically collapsed, resulting in a switch from grounded ice, or ice shelves, to open waters in the Ross embayment when planetary temperatures were up to ̃3 C warmer than today4 and atmospheric CO2 concentration was as high as ̃400 p.p.m.v. (refs 5, 6). The evidence is consistent with a new ice-sheet/ice-shelf model7 that simulates fluctuations in Antarctic ice volume of up to + 7 m in equivalent sea level associated with the loss of the WAIS and up to +3 m in equivalent sea level from the EastAntarctic ice sheet, in response to ocean-induced melting paced by obliquity.During interglacial times, diatomaceous sediments indicate high surface-water productivity, minimal summer sea ice and air temperatures above freezing, suggesting an additional influence of surface melt8 under conditions of elevated CO2. Published 322 - 328 2.2. Laboratorio di paleomagnetismo 3.8. Geofisica per l'ambiente 2.3. TTC - Laboratori di chimica e fisica delle rocce JCR Journal reserved