Approximately 12.900 years before today the Northern Hemisphere suddenly experienced a return to the ice ages which lasted 1000 years.  Prior to this period we were in a warming period  that some believe  caused the mini-ice age by seeding the Atlantic with cool waters from de-glaciation which shutdown of the North Atlantic thermophile circulation.  Strangely enough the event coincides with the same time mammoths, mega-fauna, smaller mammals, and birds suddenly became extinct in North America. Even human occupation disappeared as evidenced by the ex extinction of the Clovis culture in North America.

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