younger dryas
stoat | May 14, 2011The Younger Dryas was a cooling event about 12 kyr ago - see the wikipedia article, which still has the pic I drew in it. It is an example of rapid climate change, and was probably caused by THC shutdown caused by meltwater from the Laurentide icesheet, though exactly how is unclear.
However, some people would like it to be caused by a comet. That was first suggested in 2007, and RC said we doubt it. Then again in 2009 some more evidence was produced, and RC said we still doubt it. Others were less cautious; and Unscientifc American gushed over it as did Nat. Geog.. Bits of their work turned…