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Title: Sensitivity of the Antarctic ice sheet to evolving bed topography
When a continental sized ice sheet first formed on Antarctica across the Eocene-Oligocene boundary the bed topography was significantly different to the modern day bed. As the bed evolved due to the effects of glacial erosion, sedimentation, subsidence and tectonics, it is hypothesised that the ice sheet sensitivity to climate forcing also changed. This hypothesis has been tested in a number of recent ice sheet modelling studies, but these efforts have been limited by the use of idealised bed topography estimates. Here we explore the ice sheet sensitivity to evolving bed topography using a recently produced suite of palaeotopographies for the Eocene-Oligocene and Oligocene-Miocene transitions, the mid-Miocene climatic optimum, and the late Miocene to early Pliocene. Al- though we present results for all of these intervals, we are particularly interested in whether bed topography played a role in Antarctic ice sheet stabilisation following the mid-Miocene climatic optimum and the final descent into the icehouse.  more » « less
Award ID(s):
1664013
PAR ID:
10113495
Author(s) / Creator(s):
Date Published:
Journal Name:
Geophysical research abstracts
Volume:
21
ISSN:
1029-7006
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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