Lovelock gets it right...

It's little known even in the doom 'n gloomer blogosphere that CO2 is not the single biggest threat to climate change. It is the initial kick off, but the total warming the earth will experience will be the total set of feedback mechanisms and side effects of the initial CO2 warm up. One of these is the reduced albedo when the ice pack, snow cover, and glaciers melt. This warms the ocean faster and is a straight-forward Catch-22 situation. Ice melts, the darker ocean absorbs more heat, more ice melts, etc., etc.

Another feedback loop is the methane released by thawing Tundra. Tundra is basically frozen peat and other organic matter and when it thaws it gives off a lot of methane gas. Methane is twenty times more powerful a greenhouse gas than CO2. If methane accumulation builds alongside CO2 we have a runway situation as Dr. James Lovelock predicted. On its own melting Tundra is a severe feedback loop.

But thawing Tundra is a drop in the bucket compared to the frozen methane stored underwater in the Arctic and Antarctic. The estimates of the amount of these frozen methane hydrates is staggering and now it looks like it is, in fact, melting and off-gassing methane. This feedback loop is going to be immense and it will push all of the warming estimates to date off the charts. I've said for many years now that we will see up to three feet of ocean rise by 2015. The Methane Hydrate feedback mechanism is the basis for my prediction. The melt, once started, is going to accelerate global warming unlike anything we ever expected. And it looks like we're there...