What happened 8,200 years ago?
The climate was warm and all of a sudden, temperatures collapsed into a mini ice age for about 400 years, before returning to normal.
And this, only in the northern hemisphere.
The melting of the Canadian great lakes?
Still, a total <a href=http://www.unesco.org/courier/1999_11/uk/planete/txt1.htm">mystery.
Raoul