I read an early draft of Koonin's new book discussed in the WSJ article excerpted below, and I highly recommend it.
See also Epistemic Caution and Climate Change.
Video above is from a 2019 talk discussed in this earlier post: Certainties and Uncertainties in our Energy and Climate Futures: Steve Koonin.
My own views (consistent, as far as I can tell, with what Steve says in the talk):
1. Evidence for recent warming (~1 degree C) is strong.
2. There exist previous eras of natural (non-anthropogenic) global temperature change of similar magnitude to what is happening now.
3. However, it is plausible that at least part of the recent temperature rise is due to increase of atmospheric CO2 due to human activity.
4. Climate models still have significant uncertainties. While the direct effect of CO2 IR absorption is well understood, second order effects like clouds, distribution of water vapor in the atmosphere, etc. are not under good control. The increase in temperature from a doubling of atmospheric CO2 is still uncertain to a factor of 2-3 and at the low range (e.g., 1.5 degree C) is not catastrophic. The direct effect of CO2 absorption is modest and at the low range (~1 degree C) of current consensus model predictions. Potentially catastrophic outcomes are due to second order effects that are not under good theoretical or computational control.
5. Even if a catastrophic outcome is only a low probability tail risk, it is prudent to explore technologies that reduce greenhouse gas production.
6. A Red Team exercise, properly done, would clarify what is certain and uncertain in climate science.
Simply stating these views can get you attacked by crazy people.Buy Steve's book for an accessible and fairly non-technical explanation of these points.
WSJ: ... Barack Obama is one of many who have declared an “epistemological crisis,” in which our society is losing its handle on something called truth.
Thus an interesting experiment will be his and other Democrats’ response to a book by Steven Koonin, who was chief scientist of the Obama Energy Department. Mr. Koonin argues not against current climate science but that what the media and politicians and activists say about climate science has drifted so far out of touch with the actual science as to be absurdly, demonstrably false.
This is not an altogether innocent drifting, he points out in a videoconference interview from his home in Cold Spring, N.Y. In 2019 a report by the presidents of the National Academies of Sciences claimed the “magnitude and frequency of certain extreme events are increasing.” The United Nations Intergovernmental Panel on Climate Change, which is deemed to compile the best science, says all such claims should be treated with “low confidence.”
... Mr. Koonin, 69, and I are of one mind on 2018’s U.S. Fourth National Climate Assessment, issued in Donald Trump’s second year, which relied on such overegged worst-case emissions and temperature projections that even climate activists were abashed (a revolt continues to this day). “The report was written more to persuade than to inform,” he says. “It masquerades as objective science but was written as—all right, I’ll use the word—propaganda.”
Mr. Koonin is a Brooklyn-born math whiz and theoretical physicist, a product of New York’s selective Stuyvesant High School. His parents, with less than a year of college between them, nevertheless intuited in 1968 exactly how to handle an unusually talented and motivated youngster: You want to go cross the country to Caltech at age 16? “Whatever you think is right, go ahead,” they told him. “I wanted to know how the world works,” Mr. Koonin says now. “I wanted to do physics since I was 6 years old, when I didn’t know it was called physics.”
He would teach at Caltech for nearly three decades, serving as provost in charge of setting the scientific agenda for one of the country’s premier scientific institutions. Along the way he opened himself to the world beyond the lab. He was recruited at an early age by the Institute for Defense Analyses, a nonprofit group with Pentagon connections, for what he calls “national security summer camp: meeting generals and people in congress, touring installations, getting out on battleships.” The federal government sought “engagement” with the country’s rising scientist elite. It worked.
He joined and eventually chaired JASON, an elite private group that provides classified and unclassified advisory analysis to federal agencies. (The name isn’t an acronym and comes from a character in Greek mythology.) He got involved in the cold-fusion controversy. He arbitrated a debate between private and government teams competing to map the human genome on whether the target error rate should be 1 in 10,000 or whether 1 in 100 was good enough.
He began planting seeds as an institutionalist. He joined the oil giant BP as chief scientist, working for John Browne, now Baron Browne of Madingley, who had redubbed the company “Beyond Petroleum.” Using $500 million of BP’s money, Mr. Koonin created the Energy Biosciences Institute at Berkeley that’s still going strong. Mr. Koonin found his interest in climate science growing, “first of all because it’s wonderful science. It’s the most multidisciplinary thing I know. It goes from the isotopic composition of microfossils in the sea floor all the way through to the regulation of power plants.”
From deeply examining the world’s energy system, he also became convinced that the real climate crisis was a crisis of political and scientific candor. He went to his boss and said, “John, the world isn’t going to be able to reduce emissions enough to make much difference.”
Mr. Koonin still has a lot of Brooklyn in him: a robust laugh, a gift for expression and for cutting to the heart of any matter. His thoughts seem to be governed by an all-embracing realism. Hence the book coming out next month, Unsettled: What Climate Science Tells Us, What It Doesn’t, and Why It Matters.
Any reader would benefit from its deft, lucid tour of climate science, the best I’ve seen. His rigorous parsing of the evidence will have you questioning the political class’s compulsion to manufacture certainty where certainty doesn’t exist. You will come to doubt the usefulness of centurylong forecasts claiming to know how 1% shifts in variables will affect a global climate that we don’t understand with anything resembling 1% precision. ...
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