Reconstruction of Changes in the Weddell Sea Sector of the Antarctic Ice Sheet since the Last Glacial Maximum

The Weddell Sea sector is one of the main formation sites for Antarctic Bottom Water and an outlet for about one fifth of Antarctica's continental ice volume. Over the last few decades, studies on glacial–geological records in this sector have provided conflicting reconstructions of changes in...

Full description

Bibliographic Details
Published in:Quaternary Science Reviews
Main Authors: Hillenbrand, Claus-Dieter, Bentley, Michael J., Stolldorf, Travis D., Hein, Andrew S., Kuhn, Gerhard, Graham, Alastair G. C., Fogwill, Christopher J., Kristoffersen, Yngve, Smith, James A., Anderson, John B., Larter, Robert D., Melles, Martin, Hodgson, Dominic A., Mulvaney, Robert, Sugden, David E.
Format: Article in Journal/Newspaper
Language:unknown
Published: Digital Commons @ University of South Florida 2014
Subjects:
Antarctica
Cosmogenic nuclide surface exposure age dating
Deglaciation
Geomorphology
Glacial history
Ice sheet
Ice Shelf
Last Glacial Maximum
Radiocarbon dating
Sea level
Weddell Sea
Life Sciences
Antarctic
The Antarctic
Weddell
Antarc*
Ice Sheet
Sea ice
Online Access:https://digitalcommons.usf.edu/msc_facpub/1551
https://doi.org/10.1016/j.quascirev.2013.07.020
Description
Summary:The Weddell Sea sector is one of the main formation sites for Antarctic Bottom Water and an outlet for about one fifth of Antarctica's continental ice volume. Over the last few decades, studies on glacial–geological records in this sector have provided conflicting reconstructions of changes in ice-sheet extent and ice-sheet thickness since the Last Glacial Maximum (LGM at ca 23–19 calibrated kiloyears before present, cal ka BP). Terrestrial geomorphological records and exposure ages obtained from rocks in the hinterland of the Weddell Sea, ice-sheet thickness constraints from ice cores and some radiocarbon dates on offshore sediments were interpreted to indicate no significant ice thickening and locally restricted grounding-line advance at the LGM. Other marine geological and geophysical studies concluded that subglacial bedforms mapped on the Weddell Sea continental shelf, subglacial deposits and sediments over-compacted by overriding ice recovered in cores, and the few available radiocarbon ages from marine sediments are consistent with major ice-sheet advance at the LGM. Reflecting the geological interpretations, different ice-sheet models have reconstructed conflicting LGM ice-sheet configurations for the Weddell Sea sector. Consequently, the estimated contributions of ice-sheet build-up in the Weddell Sea sector to the LGM sea-level low-stand of ∼130 m vary considerably. In this paper, we summarise and review the geological records of past ice-sheet margins and past ice-sheet elevations in the Weddell Sea sector. We compile marine and terrestrial chronological data constraining former ice-sheet size, thereby highlighting different levels of certainty, and present two alternative scenarios of the LGM ice-sheet configuration, including time-slice reconstructions for post-LGM grounding-line retreat. Moreover, we discuss consistencies and possible reasons for inconsistencies between the various reconstructions and propose objectives for future research. The aim of our study is to provide two alternative interpretations of glacial–geological datasets on Antarctic Ice-Sheet History for the Weddell Sea sector, which can be utilised to test and improve numerical ice-sheet models.

Similar Items