And then there is this:
The person Rick Perry refers to is Steven E. Koonin. For more about him see this wiki page and the following excerpt from that page:
In “Climate Science Is Not Settled,” a 2014 essay published in the Wall Street Journal, Koonin wrote that “We are very far from the knowledge needed to make good climate policy,” and that “The impact today of human activity [on climate] appears to be comparable to the intrinsic, natural variability of the climate system itself.” Koonin criticized the use of results from climate modelling to support the “scientific consensus” (quotes in original) about climate change, noting that, among other problems, “The models differ in their descriptions of the past century’s global average surface temperature by more than three times the entire warming recorded during that time.” Regarding climate sensitivity, Koonin wrote that “Today’s best estimate of the sensitivity (between 2.7 degrees Fahrenheit and 8.1 degrees Fahrenheit) is no different, and no more certain, than it was 30 years ago. And this is despite an heroic research effort costing billions of dollars.”
Ten days after Koonin wrote this, Jeffrey Kluger in Time  called Koonin’s piece disingenuous if not dishonest. Koonin simply used the old debating trick of setting up a strawman to knock down by misconstruing what climate scientists mean when they say the climate debate is “settled.” “…they mean that the fake debate over whether climate change is a vast hoax is finished,” writes Kluger. He goes on to state that every point Koonin made is and has for years been widely acknowledged by climate scientists, very few of whom utilize the kind of overzealous language their critics commonly use.
Mr Koonin is a theoretical physicist. He is not a climate scientist. Having served as U.S. Department of Energy’s second Senate-confirmed Under Secretary for Science serving from May 19, 2009 through November 18, 2011 he is also a politician. Search his bio and although there is no doubt he’s a scientist of high order it’s hard to find where he’s specialized in anything to do with climate, paleoclimatology, geology, or geophysics….