Wisconsin glaciation

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The Wisconsin (North America), Weichsel (Scandinavia) or Würm (the Alps) glaciation was the most recent period of the Ice Age, ending some ten thousand years ago. Please note that the term Ice Age refers to all the periods of glaciation during the Pleistocene (2,5 mya - 10 000 BP(Beyond Present)). The Wisconsin/Weichsel/Würm glaciation starts at ca 70 000 BP, reaches it's maximum ice-sheet at 18 000 BP (in Europe it reaches southern Germany). The heaviest pressure of the Weichsel-glaciation was in northern Sweden and Finland where the land is still rising with more than a metre per year. In Scandinavia only the western parts of Jolland were ice-free during the glaciation and a large part of the now-a-days North Sea was dry land connecting Jolland with Britain. It's also in Denmark the only finds of so-called ice-age animals that are older than 13 000 BP are found (in Scandinavia that is). In the period after the last interglacial period before the current one (Eemian) the coast of Norway was also ice-free. The Baltic Sea with it's unique brackish water is a result of the meltwater from the Weichsel glaciation being combined with the saltwater of the North Sea when the straits between Sweden and Denmark opened ca 7 000 BP.

It radically altered the geography of North America north of the Ohio River. On Kelly's Island in Lake Erie and other parts of Ohio the scour marks left by these glaciers can be easily observed.

The Great Lakes are the result of pooling of glacial meltwater at the rim of the receding glaciers. When the enormous mass of the continental ice sheet retreated the Great Lakes began gradually moving south due to isostatic rebound of the north shore. Niagara Falls is also a product of the glaciation, as is the course of the Ohio River, which largely supplanted the prior Teays River.

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