“The Younger Dryas which actually occurred when we seemed to be in the warming phase after the last ice age was likely caused by a major boloid event in the Northern Hemisphere.”
Furthering the same theory: the shock and heating of the ice sheet caused a huge chunk of ice over 1K thick and about the size of Greenland to slide off the ice sheet into the North Atlantic, blocking the Gulf Stream.
It could also have been caused by a huge surge of cold melt water and ice chunks flooding the North Atlantic