That dozen is, of course, enough to melt the ice caps, displaying most of the world's population, as most of the world's population lives on coastlines.
Is that a baker's dozen or?
The biggest threat is to agriculture, and a threat of flooding to low-lying regions - generally, that's third-world asian nations. Hurricanes are still up in the air (no pun intended) with arguments that they'll get worse/get better in the scientific literature.
Spread of disease may also be an issue - climate change may allow some previously tropical diseases to spread out a bit more.
Oh, and some theories of the dinosaur's demise posit climate change as the cause - and not in the sense of "the climate changed because a bloody great meteorite hit the Earth"
what i have to say about global warming is earth doesnt go in a straight circle so sometimes its closer to the sun and sometimes its not. i think the scientists know this but they want their pay.or they are just thinking for more complicated soulutions