Believe it or not, the above prediction now seems to underestimate the problem, because it only takes into consideration human emissions. Recently it has been discovered that gigantic methane deposits under the ocean have destabilized from the heat pulse hitting the Arctic:

“…Researchers were investigating “alarming” reports in the last few days of the release of methane from long frozen Arctic waters, possibly from the warming of the sea…” –”Arctic sea ice drops to 2nd lowest level on record,” AP, 27 Aug '08

http://mwcnews.net/content/view/24997&Itemid=1

“If the Siberian (submarine) permafrost-seal thaws completely and all the stored gas escapes, the methane content of the planet's atmosphere would increase twelve fold. The result would be catastrophic global warming.” –”A Storehouse of Greenhouse Gases Is Opening in Siberia,” Spiegel, 17 April '08

BOB GARFIELD: Now, when I saw the word, I immediately understood, yeah, got loca – vore – got it – locally-grown produce. Does anyone actually use it?

BEN ZIMMER: Well, it’s being used quite a lot by the local food movement, either locavore, or there’s another variant form that’s often used – localvore, with an extra L in the middle. And at the moment, those two forms are battling it out a little bit. But the original form and currently the more popular form is locavore.