Source: Journal of Geophysical Research-Atmospheres (JGR-D) paper 10.1029/2009JD012105, 2009; http://dx.doi.org/10.1029/2009JD012105
7. Ancient Antarctica had more room for ice than was thought
About 34 million years ago, during the Eocene-Oligocene transition, Earth's climate shifted from warmer to cooler. Models for the growth of the Antarctic ice sheet during that transition show a lot of ice in East Antarctica but very little in West Antarctica. Other data, however, indicate that much more ice must have existed than those models predict, so climate scientists had trouble explaining where all the ice formed. To resolve the issue, Wilson and Luyendyk create a new model of the topography of Antarctica around 34 million years ago, taking into account several geologic factors that have affected topography since the Eocene-Oligocene transition but have not been considered in other models. Their reconstruction shows that West Antarctica had a higher elevation 34 million years ago than previously thought. This adds about 10-20 percent to the total land area above sea level, creating additional area that could have held ice during the formation of the Antarctic ice sheet. The authors believe the study will help improve understanding of the formation of Antarctic ice and will be useful for global climate models.
See previous press release at: http://www.agu.org/sci_soc/prrl/2009-23.html
Title: West Antarctic paleotopography estimated at the Eocene-Oligocene climate transition
Douglas S. Wilson: Marine Science Institute, University of California, Santa Barbara, California, USA and Department of Earth Science, University of California, Sant
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American Geophysical Union