Admittedly factual data is in no short supply from UNFCC. The graph in the Economist is certainly a nice picture but hopefully few will decide policy on such evidence, or will they? Some comments bring vividly to mind a recent TV documentary of Luxury Tourism in the Artic in which all of the local population interviewed, think, and no feel is better, that a bit of GW is a very nice thing. As a Northern Brit myself, I surmise that many feel that "if sustainable", a bit more GW would be just the job. (And we do know how to heat things up if needed, n'est ce pas?)
cf. my blog and link to Nature on the "cultural prism and the local effect on presentation of Scientific work (IPCC are supposed to be the best).
Recall. The humble objective quoted from UNFCCC
"The ultimate objective of the Climate Change Convention (UNFCCC) is to achieve " stabilization of greenhouse gas concentrations in the atmosphere at a level that would prevent dangerous anthropogenic interference with the climate system." cf. UNFCC ref. link