All the predictions of dramatic impending warming and ancillary calls for strong government action are based on conjecture

See Hooper and Henderson on Patrick Frank by David Henderson of EconLog.

"Patrick Frank is a scientist at the Stanford Synchrotron radiation Lightsource (SSRL), part of the SLAC (formerly Stanford Linear Accelerator Center) national Accelerator Laboratory at Stanford University. The SSLR produces extremely bright x-rays as a way for researchers to study our world at the atomic and molecular level. In a bit of a shift, Frank has shone a bright light on general circulation models (GCMs)--models used to predict long-term changes in climate--and illuminated some fatal flaws. His bottom line is that these models, as they stand today, are useless for helping us understand the relationship between greenhouse gas emissions and global temperatures. This means that all the predictions of dramatic impending warming and ancillary calls for strong government action are based on conjecture.

These are the opening two paragraphs in Charles L. Hooper and David R. Henderson, "A Fatal Flaw with Climate Models," Regulation, Winter 2016-2017. A key paragraph:

The IPCC has looked at a number of different cases and it reports that temperatures could be, in the worst case, up to 4 ̊C higher by 2100. However, based on Frank's work, when considering the errors in clouds and CO2 levels only, the error bars around that prediction are ±15 ̊C. This does not mean--thankfully-- that it could be 19 ̊ warmer in 2100. Rather, it means the models are looking for a signal of a few degrees when they can't differentiate within 15 ̊ in either direction; their internal errors and uncertainties are too large. This means that the models are unable to validate even the existence of a CO2 fingerprint because of their poor resolution, just as you wouldn't claim to see DNA with a household magnifying glass.

Charley discovered Professor Frank on line. See the Readings at the end of the piece for the items we read and watched. So we took him for coffee up at Stanford in October. It was a scintillating conversation, not only about the science and his struggles with getting editors of climate science journals to understand confidence intervals, but also about his own personal immigration story. I told him that this was actually the most exciting intellectual interaction I had had that year. He answered that I need to get out more. Both statements are true."