Well, the Intergovernmental Panel on Climate Change has stepped back from issuing one estimate of projected temperature ranges in favor of stating the individual ranges for each “storyline” – which are basically futurist exercises saying how rich we will become (and by their logic, the richer we are, the more in danger we are, which is a novel approach). It seems that the numbers I wrote about yesterday referred to climate sensitivity, which is a different thing from temperature projections, a point the reporters hadn’t sufficiently gathered. I should have spotted that, so I apologize.Overall, there’s nothing really new in the Summary. The news that the IPCC has moved its attribution of global warming to man’s activities from “likely” to “very likely” is a bit of a damp squib, as we’ve been told since the last report by everyone with a computer model that there was no room for doubt about man’s involvement. Yet the IPCC still admits we know very little about the role of aerosols, land use changes, contrails, water vapor and solar irradiance on global temperature, so they admit they make that assertion without full knowledge of the facts.Also, gone from the Summary is the icon of the Third Assessment Report – the “hockey stick” graph. The fact that it took two amateurs to get the scientists to realize the hole in their argument there is indicative of the state of climate science today. The IPCC has been wrong in the past. The fact that there’s nothing really new in this document suggests that as we learn more about the science, yes we may well find more evidence of human involvement in the climate, but when all’s said and done it won’t amount to anything to worry about. If we go down the road of emissions suppression, however, that will be something to worry about. We could stabilize emissions at a cost to the world of 5 percent of GDP (bear in mind that the Iraq War is costing America 0.8 percent of GDP and the world as a whole a lot less) and still have warming or we can all get richer and more resilient. That’s really the choice on the table.