climate sensitivy

This is just one of dozens of responses to common climate change denial arguments, which can all be found at How to Talk to a Climate Sceptic. Objection: Taking into account the logarithmic effect of CO2 on temperature, the 35% increase we have already seen in concentrations represents about 3/4 of the total forcing to be expected from a CO2 doubling. Since we have warmed about .7oC so far, we should only expect about .3oC more for a doubling from pre-industrial levels, so about 1oC not 3oC as the scientists predict. Clearly the climate model sensitivity to CO2 is much too high. Answer: Even…