[eloff]

That's my way of thinking about it too. At any rate getting nearly 200 independent nation states to agree on anything when they all individually benefit by flouting the rules - that's madness. We'll burn oil and coal and gas until it doesn't make economic sense. I very much doubt politics will change the outcome. Technology will hopefully save us from ourselves on that front.

A bigger problem is positive feedback loops. Melting ice means more dark water to absorb sunlight, and more melting. Melting permafrost releases CO2 and Methane and causes more warming. And somewhere around ~5 degrees warming the frozen methane on the ocean floor will bubble up and cause the mother of all feedback cycles. We'd be in for about 10 degrees warming and a mass extinction that would wipe out 90% or more of all species on Earth. From what I've seen of global warming predictions we won't get there - but I'm mentioning this because at some point warming temperatures doesn't just mean major changes and flooding our cities - at some point it means a terrible calamity like the Earth has only occasionally seen.

[refurb]

A bigger problem is positive feedback loops.

Historically we've had much more CO2 in the atmosphere than we do now. Why didn't the methane bubble up and kill everything then?

[nikdaheratik]

The methane was primarily caused by decaying biomass falling to the ocean floor. It didn't exist at the time the CO2 levels were higher.

[eloff]

It did. That was part of the sad chain of events causing one of the biggest mass extinctions ever 250m years ago. Its one of the theories anyway.