It may have been weather, the article linked above indicates that the "Volcanic Winter" lasted 6 years, but the Ice Age it kicked off lasted 1,000 years. That's Climate Change with a vengence. Just not man made.
Unless it was those Sumatran religious nuts throwing the virgins into the volcano. :)
I'm trying to reconcile the Toba event (70-75,000 years ago) and the Hobbits on the nearby island of Flores...the Hobbit skeletons range in age from 80,000 to 12-13,000 years ago. I wonder how their DNA plays into all these DNA analysis's?