This cartoon shows each countries carbon emissions, China and the USA are by far leading the way.  If China do actually agree to the Durban protocol (when they decide the fine details) then a considerable drop in emissions could occur. This cartoon nicely highlights why Kyoto failed, as the worlds 2nd biggest emitter failed to sign up. Many of the coastal countries that depend heavily on the oceans for food and money have very low emissions yet are at the greatest threat from ocean acidification.