The West Antarctic Ice Sheet first grew 20 million years earlier than previously thought
(23 September 2013)
The team reconstructed the ancient landscape of West and East Antarctica and showed that West Antarctica was significantly higher in elevation in the past, and did not lie below sea level as it does today.
An ice sheet model showed that significant ice could be supported in West Antarctica at a time when global climate evolved from ‘greenhouse’ to 'icehouse' conditions. Previous simulations were unable to produce the correct volume of ice because neighbouring East Antarctica alone could not support it. This was the missing ice problem.
The results mark the beginning of a new paradigm for our understanding of the age and history of Earth's great global ice sheets. It also shows that the 'missing ice' was formed in West Antarctica as a result of high topography, and not in the Northern Hemisphere where scientists had hitherto assumed the ice must have existed.
The research, published in Geophysical Research Letters, was led by Dr Doug Wilson at the University of California, Santa Barbara, and is part of the ANTscape project to reconstruct the past geography of Antarctica.
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