- #1
Andre
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Multiple evidence suggest that the Pleistocene epoch (2.56 Million years - 11.6 thousand years) was about waxing and waning Ice sheets with the pace of the milankovitch wobbles superimposed on the Earth orbit.
One intriguing element showing this is a multiple multi-millenium cycle in variation of isotope ratios in foraminifera remains in the ocean sediments, which all show the same pattern, which is also matched in the ice cores of Antarctica.
This cyclic variation in isotopes is thought to be basin effect in pace with the waxing and waning of the ice sheets. Evaporation favors light isotopes, escaping much more easily from the liquid condition into gas. Hence if the ice sheets are growing with more light isotopes, the concentration of heavy isotopes in the ocean is increasing. And it is thought that this is reflected in the isotope ratio in the biota sediments. This is considered to be easily quantifiable and hence the isotope ratios in the ocean cores are considered to be a proxy for ice volume.
http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6VGS-45J8YCC-1&_user=10&_rdoc=1&_fmt=&_orig=search&_sort=d&view=c&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=e199a166e433e314a5f3a9cbbe5cdbc6 model those quantities for the last glacial maximum as function of contribution to sea level rise and propose:
Now let’s focus on that 65 meters stored in the Eurasian continent. Bintanja shows the essence of the publication on his webside
http://www.phys.uu.nl/~bintanja/Fig_lgm.jpg
One intriguing element showing this is a multiple multi-millenium cycle in variation of isotope ratios in foraminifera remains in the ocean sediments, which all show the same pattern, which is also matched in the ice cores of Antarctica.
This cyclic variation in isotopes is thought to be basin effect in pace with the waxing and waning of the ice sheets. Evaporation favors light isotopes, escaping much more easily from the liquid condition into gas. Hence if the ice sheets are growing with more light isotopes, the concentration of heavy isotopes in the ocean is increasing. And it is thought that this is reflected in the isotope ratio in the biota sediments. This is considered to be easily quantifiable and hence the isotope ratios in the ocean cores are considered to be a proxy for ice volume.
http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6VGS-45J8YCC-1&_user=10&_rdoc=1&_fmt=&_orig=search&_sort=d&view=c&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=e199a166e433e314a5f3a9cbbe5cdbc6 model those quantities for the last glacial maximum as function of contribution to sea level rise and propose:
Model simulations show that at the last glacial maximum (LGM) a volume of ice representing about 65 m of sea level equivalent is stored on the Eurasian continent, whereas North America stores 42 m. The other regions (Greenland, Tibet, South-America and Antarctica) contribute about 17 m to global sea level lowering at the LGM compared to present day
Now let’s focus on that 65 meters stored in the Eurasian continent. Bintanja shows the essence of the publication on his webside
http://www.phys.uu.nl/~bintanja/Fig_lgm.jpg
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