An Inconvenient Prize?

Can somebody please tell me why Al Gore won the Nobel PEACE Prize? Forgive me for my ignorance, but I always thought that prize went to somebody who, ya know, worked to bring PEACE to the world or to an area that has not known peace.

Recent winners have included a guy who tried to prevent nuclear energy from being used for military purposes, a guy who formed a bank to provide loans to people in extremely impoverished areas and a woman who stood up against political oppression in Kenya. Now, regardless of what you think about global warming, how exactly does raising awareness about the issue equate to bringing peace to the planet? I'm honestly stymied.