Last week, an advance copy of a paper to appear in the Proceedings of the National Academy of Sciences (PNAS) was released which reported that a collection of “experts” suggests that climate tipping points (codename for something bad but we don’t know exactly what) would be knocked over by 2200 if we stay on our current greenhouse gas emissions pathway (for about the next 200 years). Underlying these views is the experts’ opinions as to what the earth’s equilibrium climate sensitivity—the rise in global temperatures resulting from a doubling of the earth carbon dioxide concentration—likely is.
But do the experts opinions actually reflect the scientific knowledge on these subjects?
The answer is no.
In fact, the experts’ opinions tended towards the extreme, despite recent science which should have reeled them in.…