Summary
November 11, 2009: The latest evidence suggests that the Younger Dryas mini ice age took less than 3 years to be in full force in Europe, possibly just a few months to go from no signs to full-on "Big Freeze". The new evidence comes in the form of more detailed analysis of ever-thinner slivers of glacial ice, suggesting that severe sudden cold caused the lakes of Europe to go dead in a matter of months. The evidence now suggests that melting ice slowed the gulf stream, and resulted in near-instantaneous climate change in the opposite direction - so warmer years directly contributed to much colder years immediately thereafter, which in turn lead to (among other things) the decline of the clovis culture in North America.
The Younger Dryas started about 12,800 years ago, and lasted 1,300 years.
Source
Game and Story Use
- A sudden climate change would be a major disaster, with plenty of drama and conflict. Just make sure you've got good rules for weather and arctic survival.
- Sounds like a plan by a mad scientist or supervillain - "I will disrupt the gulf stream and cause an ice age, unless you give in to my demands for 1 billion dollars and Superman's secret identity!"