Are you saying Hansen’s projections in this paper assume Kyoto is implemented? Including the US?
What would Hansen’s projection be if Kyoto is not implemented?
The question is:
Are Hansen’s modest temperature projections due to the continuation of economic and physical forces in play from 1980 to the present or due to some new set of regulations (e.g. Kyoto)?
Response: I recommend you read the paper (or a recent popular summary) for the detailed answers, but essentially Hansen posits that concentrations of key atmospheric forcings (especially methane and black carbon) can be realistically controlled more effectively than the standard scenarios allow. – gavin