Greenland 2009 Greenland Margin Ice sampling and the Cause of the Younger Dryas What caused the Younger Dryas, a period of dramatic climate change that coincided with the extinction of many large North American land mammals and a shift in Paleo-Indian culture? In 2008 Climate Change Institute  scientists Paul Mayewski, Andrei Kurbatov and Jørgen Peder read more Margin Ice Sampling and the Cause of the Younger Dryas