The ideal global warming game, it seems to me, would be a detailed simulation of the global climate as well as the global economy -- and preferably one that would allow you to tinker with the assumptions, both at the macro and micro level. At the macro level, I'm imagining scenarios ranging from "We're all doomed!" to "Bah, the Copenhagen Consensus has it right," and at the micro allowing you to twiddle individual knobs (e.g., "nuclear power plants are safe as houses" to "they go blooey with alarming frequency").
Climate Challenge is not the ideal global warming game -- but it's surprisingly engaging.
