UPDATE: The UN is downplaying the level they believe man has impacted the climate.
The Ross Ice Shelf, the largest ice piece of ice in the world which just so happens to be the size of France, has shrunk and enlarged throughout time according to a new study.
For those who want a fairly quick read on climate change the U.S. Senate just released the reader-friendly report entitled "Skeptic's Guide to Debunking Global Warming" for free. The title is a bit of a misnomer. The report does acknowledge climate change and hits historic aspects well (Greenland was called "green land" for a reason).
I think Harm de Blij said it best. The event is probably mostly natural but it humans still must make plans to work with it.