05-10-2008, 09:18 AM
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#92 (permalink)
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Banned
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Quote:
Originally Posted by Tully Mars
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Quote:
http://www.sciencedaily.com/releases...0705153019.htm
Fossil DNA Proves Greenland Once Had Lush Forests; Ice Sheet Is Surprisingly Stable
ScienceDaily (Jul. 5, 2007)
..Climate theories over-turned
The research results are the first direct proof that there was forest in southern Greenland. Furthermore Willerslev found genetic traces of insects such as butterflies, moths, flies and beetles. But when was that? According to most scientific theories to date, all of southern Greenland and most of the northern part were ice-free during the last interglacial period 125,000 years ago, when the climate was 5 degrees warmer than the interglacial period we currently live in.
This theory however, was not confirmed by Willerslev and co-workers subsequent datings. He analysed the insects' mitochondria, which are special genomes that change with time and like a clock can be used to date the DNA. He also analysed their amino acids which also change over time. Both datings showed that the insects were at least 450,000 years old....
...The dating of dust particles also showed that it has been at least 450,000 years ago since the area of the DYE-3 drilling, in the southern part of Greenland, was ice-free.
Sea Level Rise?
That signifies that there was ice there during the Eemian interglacial period 125,000 years ago. It means that although we are now confronted with global warming, the whole ice sheet will probably not melt.
Please note: The scientists do not want to put into question the rise in sea level predicted to occur due to global warming. During the last interglacial period 125.000 years ago, temperatures in Greenland were 5 degrees higher and global sea level was 4-5 meters higher than it is today. However, since the new scientific results show that the ice sheet also covered southern Greenland, the melting of the Greenlandic ice cap can only have caused a sea level rise of about 2 meters. Therefore some of the melting ice contributing to the sea level rise must have come from other sources, for instance the Antarctic. Furthermore, thermal warming of the oceans will cause expansion of the sea water and result in a sea level rise of half a meter, and the melting of small glaciers around the globe will likely result in an additional half meter rise.
The results have just been published in the journal Science.
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