Pat Michaels writes at Cato.org:
The IPCC is really in a pickle. Not only can it be blamed for the lack of any effective (unnecessary) national climate policy, but it is about to produce a report that is going to be obsolete the minute it is published.
Over the years, the IPCC has behaved like a treed cat. Instead of closing its eyes and scurrying to the ground, it climbs onto even higher and thinner branches, while yowling ever louder. How does it back down from a quarter-century of predicting a quarter of a degree (Celsius) of warming every decade, when there’s been none for 17 years now?
In fact, as I demonstrated in a recent presentation to the American Geophysical Union, the reigning suite of climate models has now officially failed, with the difference between them and reality now statistically significant at the 1-in-20 level.
Since the beginning of 2011, at least 16 separate experiments published by nearly 50 researchers show that the “sensitivity” of temperature to carbon dioxide that is characteristic of the IPCC’s climate models is simply too high. “Sensitivity” is the amount of temperature change expected for a nominal doubling of atmospheric carbon dioxide.