Quick Search:    advanced search

GSW Home   GeoRef Home   My GSW Alerts   Contact GSW   About GSW   Journals List   Help

This Article Figures Only Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Mackintosh, A. Articles by Fanning, P. C. Search for Related Content GeoRef GeoRef Citation

Exposure ages from mountain dipsticks in Mac. Robertson Land, East Antarctica, indicate little change in ice-sheet thickness since the Last Glacial Maximum

¹ School of Geography, Environment and Earth Sciences and Antarctic Research Centre, Victoria University of Wellington, P.O. Box 600, Wellington 6140, New Zealand
² Department of Physical Geography, Macquarie University, Sydney, NSW 2109, Australia
³ Australian Nuclear Science and Technology Organisation (ANSTO), PMB 1, Sydney, NSW 2234, Australia
⁴ Department of Physical Geography, Macquarie University, Sydney, NSW 2109, Australia
⁵ Graduate School of the Environment, Macquarie University, Sydney, NSW 2109, Australia

Past changes in East Antarctic Ice Sheet (EAIS) volume are poorly known and difficult to measure, yet are critical for predicting the response of the ice sheet to modern climate change. In particular, it is important to identify the sources of sea-level rise since the Last Glacial Maximum (LGM), and ascertain the present-day stability of the world's largest ice sheet. We present altitudinal transects of ¹⁰Be and ²⁶Al exposure ages across the Framnes Mountains in Mac. Robertson Land that allow the magnitude and timing of EAIS retreat to be quantified. Our data show that the coastal EAIS thinned by at most 350 m in this region during the past 13 k.y. This reduction in ice-sheet volume occurred over a 5 k.y. period, and the present ice-sheet profile was attained ca. 7 ka, in contrast to the West Antarctic Ice Sheet, which continues to retreat today. Combined with regional offshore and terrestrial geologic evidence, our data suggest that the reduction in EAIS volume since the LGM was smaller than that indicated by contemporary ice-sheet models and added little meltwater to the global oceans. Stability of the ice margin since the middle Holocene provides support for the hypothesis that EAIS volume changes are controlled by growth and decay of Northern Hemisphere ice sheets and associated global sea-level changes.

Key Words: East Antarctic Ice Sheet • Last Glacial Maximum • exposure dating • sea level • ice-sheet model • Meltwater Pulse 1A

This article has been cited by other articles:

				P. Bierman Cosmogenic glacial dating, 20 years and counting Geology, June 1, 2007; 35(6): 575 - 576. [Full Text] [PDF]