Abstract

Observations and model experiments highlight the importance of ocean heat in forcing ice sheet retreat during the present and geological past, but past ocean temperature data are virtually missing in ice sheet proximal locations. Here we document paleoceanographic conditions and the (in)stability of the Wilkes Land subglacial basin (East Antarctica) during the mid-Miocene (~17–13.4 million years ago) by studying sediment cores from offshore Adélie Coast. Inland retreat of the ice sheet, temperate vegetation, and warm oligotrophic waters characterise the mid-Miocene Climatic Optimum (MCO; 17–14.8 Ma). After the MCO, expansion of a marine-based ice sheet occurs, but remains sensitive to melting upon episodic warm water incursions. Our results suggest that the mid-Miocene latitudinal temperature gradient across the Southern Ocean never resembled that of the present day. We demonstrate that a strong coupling of oceanic climate and Antarctic continental conditions existed and that the East Antarctic subglacial basins were highly sensitive to ocean warming.

Details

Title
Southern Ocean warming and Wilkes Land ice sheet retreat during the mid-Miocene
Author
Sangiorgi, Francesca 1   VIAFID ORCID Logo  ; Bijl, Peter K 1 ; Passchier, Sandra 2 ; Salzmann, Ulrich 3 ; Schouten, Stefan 4 ; McKay, Robert 5 ; Cody, Rosemary D 5 ; Pross, Jörg 6 ; van de Flierdt, Tina 7   VIAFID ORCID Logo  ; Bohaty, Steven M 8 ; Levy, Richard 9   VIAFID ORCID Logo  ; Williams, Trevor 10 ; Escutia, Carlota 11   VIAFID ORCID Logo  ; Brinkhuis, Henk 12 

 Department of Earth Sciences, Marine Palynology and Paleoceanography, Laboratory of Palaeobotany and Palynology, Utrecht University, Utrecht, The Netherlands 
 Department of Earth and Environmental Studies, Montclair State University, Montclair, NJ 07043, USA 
 Department of Geography and Environmental Sciences, Faculty of Engineering and Environment, Northumbria University, Newcastle upon Tyne, UK 
 NIOZ Royal Netherlands Institute of Sea Research, Landsdiep 4, 1797 SZt Horntje, Texel, The Netherlands; Department of Earth Sciences, Organic Geochemistry, Utrecht University, Utrecht, The Netherlands 
 Antarctic Research Centre, Victoria University of Wellington, Wellington, New Zealand 
 Paleoenvironmental Dynamics Group, Institute of Earth Sciences, Heidelberg University, Heidelberg, Germany 
 Imperial College London, Department of Earth Science and Engineering, South Kensington Campus, London, UK 
 Ocean and Earth Science, University of Southampton, National Oceanography Centre Southampton, Southampton, UK 
 Department of Paleontology, GNS Science, Lower Hutt, New Zealand 
10  International Ocean Discovery Program, Texas A&M University, College Station, TX, USA 
11  Instituto Andaluz de Ciencias de la Tierra, CSIC-University of Granada, Armilla (Granada), Spain 
12  Department of Earth Sciences, Marine Palynology and Paleoceanography, Laboratory of Palaeobotany and Palynology, Utrecht University, Utrecht, The Netherlands; NIOZ Royal Netherlands Institute of Sea Research, Landsdiep 4, 1797 SZt Horntje, Texel, The Netherlands 
Pages
1-11
Publication year
2018
Publication date
Jan 2018
Publisher
Nature Publishing Group
e-ISSN
20411723
Source type
Scholarly Journal
Language of publication
English
ProQuest document ID
1989905550
Copyright
© 2018. This work is published under http://creativecommons.org/licenses/by/4.0/ (the “License”). Notwithstanding the ProQuest Terms and Conditions, you may use this content in accordance with the terms of the License.