Naked Science Forum
Non Life Sciences => Geology, Palaeontology & Archaeology => Topic started by: thedoc on 08/11/2011 17:14:45
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How stable is the West Antarctic ice sheet. It’s one of the biggest questions in Climate Science. After all, if the ice itself melted then global sea levels could rise by between 3 and 5 metres, and that would be a catastrophe. To work out how stable the ice sheet has been in the past, scientists at the University of Exeter has been using a process known as cosmogenic isotope dating....
Read a transcript of the interview by clicking here (http://www.thenakedscientists.com/HTML/content/interviews/interview/1853/)
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Very interesting research.
This needs to be correlated with the previous research on diatom genomic drift on both sides of the West Antarctic Ice Sheet.
And there needs to be a better hand-waving explanation of higher sea levels during previous interglacial periods.
However, it is good to realize the slow nature of events in the Antarctic, with hundreds of thousands of year ice build-up not being lost in a few decades.
How would seasonal ice affect the beryllium research? Has any of this been correlated with the Antarctic Peninsula which has more of a seasonal ice covering, at least during the Holocene. Are there sections of the Antarctic Peninsula that would have had an ice cap during the glacial periods, and seasonal ice during the interglacial periods?
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And there needs to be a better hand-waving explanation of higher sea levels during previous interglacial periods.
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The Earth has a very asymmetric geography. The Northern Hemisphere is roughly 50/50 land/water; the Southern Hemisphere is roughly 10/90. There is almost no land in the zone between 45°S and 70°S where one would expect any ice age extension of the ice cap to occur. Between 45°N and 70°N it is quite a different story!
During the ice ages, an ice cap covered much of Europe, Asia and North America. During interglacials it retreats to a small area in Greenland.
In the Southern hemisphere the Antarctic ice cap presumably extended to cover the Antarctic peninsula and Patagonia. It did not reach Australia as far as I know. The greater proportion of the Southern ice cap remains over most of the Antarctic continent during interglacials.
It follows then that Southern events make only a minor contribution to the sea level rise in the interglacials, and that nearly all of the rise can be attributed to ice cap melting in the North.