I would normally ignore a book by a non-climate scientist promising “the truth about climate science that you aren’t getting elsewhere,” because such language is a red flag. But I’ve known the author of Unsettled, Steven Koonin, since I took his quantum mechanics course as a PhD student at Caltech in the 1970s. He’s smart and I like him, so I’m inclined to give his book a chance.

But smart scientists aren’t always right, and nice guys are still prone to biases—especially if they listen to the wrong people. In an apparent quest for fairness when he led a committee of the American Physical Society (one of my professional organizations) to assess its statement on climate change, Koonin recruited three scientists to represent the 97 percent consensus along with three contrarians, presumably to speak for the other 3 percent [the actual consensus is over 99 percent; see “The Consensus on Anthropogenic Global Warming” in the November/December 2015 SI]. The lack of proportionate representation amplified the contrary opinions that he heard—and only in one direction. He completely ignored another, equally unfounded, contrary view. The position sometimes referred to as “doomism” (the belief that the worst case is inevitable and it is too late to prevent it) was not represented.

The three contrarians had a long and well-documented history of engaging in ad hominem attacks on mainstream climate scientists and misrepresenting their work. Most of the technical mistakes and misrepresentations in Unsettled may simply be attributable to Koonin’s trust of those advisors and lack of rigorous independent verification.

Unfortunately, Unsettled is a book you can accurately judge by its cover. Koonin’s title hints at a logical fallacy called the “strawman” argument. The blurb on the flap confirms this with its opening sentence: “When it comes to climate change, the media, politicians, and other prominent voices have declared that ‘the science is settled.’” 

A whit of fact checking by the author or publisher would have shown that this claim is not true. In fact, Koonin makes use of an old strawman concocted by opponents of climate science in the 1990s to create an illusion of arrogant scientists, biased media, and lying politicians—making them easier to attack.

The phrase “science is settled” is repeated as Koonin’s target throughout the book, even though it has never been in common use by climate scientists and their supporters. If it were, then Google and LexisNexis searches would surely turn up instances, but the opposite is true. All the examples I found were from critics claiming that advocates of the consensus had said it. The earliest published use I found was a July 11, 1996, letter to the Wall Street Journal from prominent denier Fred Singer, falsely claiming that the IPCC report had been inappropriately tampered with for political purposes and that “politicians and activists” were “anxious to stipulate that the science is settled.”

Singer’s strawman gained traction a year later when William O’Keefe, the chairman of Global Climate Coalition (a lobbying organization opposed to climate action) claimed in a statement to Congress that “the [Clinton] Administration repeatedly quotes that [IPCC] sentiment out of context in its statements that the ‘science is settled.’” It stands to reason that repeated use of the phrase “the science is settled” would be found in searches if true. Searches do, however, turn up (in the White House archive) what Bill Clinton actually said only two weeks before Singer’s letter: “The science is clear and compelling: We humans are changing the global climate.” Nobody could argue with that at the time, nor can they now; even climate change deniers accept that human activity has altered the climate.

There are many examples of physical problems that are difficult to model, have large uncertainties and unpredictable outcomes, put people at risk, and require policy decisions and international treaties. My primary field of planetary defense is one. It’s a clear and compelling fact that Earth will be hit by another asteroid. We just don’t know where, when, or how bad it will be. The recent reentry of an errant Chinese upper stage rocket provides a more concrete analogy. The fact that its orbit would decay and it was going to come down was not in question and could rightly be called “a settled fact.” Various models had huge uncertainties, disagreed with one another, and could not predict the reentry location. But those inadequacies cannot be used as evidence for any absurd claim that it was going to stay in orbit. Anyone taking that position would be guilty of the same logical fallacy (called “impossible expectations”) that Koonin directs toward climate science.

Another example of a strawman argument in Unsettled is the claim that the term climate change denial is intended to invoke Holocaust denial. Koonin says, “I find it particularly abhorrent to have a call for open scientific discussion equated with Holocaust denial, especially since the Nazis killed more than two hundred of my relatives in Eastern Europe.” I do not doubt the sincerity of his anger, but it is misdirected.

Again, it’s aimed at a strawman. Climate change deniers are (by definition) not asking for open scientific discussion. The term denier is reserved for those who simply deny. There is also no evidence that the term climate change denial is intended to invoke Holocaust denial. Ironically, this connection was first made by the late Hollywood screenwriter Michael Crichton, speaking at a 2003 lecture at Caltech, where Koonin was provost. The word denier literally means “one who denies,” and the term has been used this way since the 1400s. The term Holocaust denier didn’t come into widespread use until the 1980s. By the early 1990s, denier was independently being used to describe those who deny the science of climate change.

Furthermore, it is climate scientists, not deniers, who have been compared to Nazis and perpetrators of genocide. In fact it was Crichton himself, in the appendix to his 2004 book State of Fear, who directly equated climate scientists to eugenicists who had a role in the “killing of ten million undesirables.” Crichton also explicitly compared climate scientists to Trofim Lysenko, whose work he described as resulting in “famines that killed millions and purges that sent hundreds of dissenting Soviet scientists to the gulags or the firing squads.” Nevertheless, Koonin praises Crichton and cites State of Fear as evidence that he was an “outspoken advocate for scientific integrity” who “looked askance at the public presentation of climate science.”

Whether one thinks it is more abhorrent to be described by the same word as those who deny other things, including the Holocaust, or to be explicitly equated to those who carried out the Holocaust is a matter of personal opinion but may indicate unconscious bias. Koonin’s bias became evident in the introduction by his use of biased language. Climate scientists “adjust model results to obfuscate shortcomings.” “Climate alarmism has come to dominate US politics.” By speaking openly about uncertainty, he had “inadvertently broken some code of silence, like the Mafia’s omerta.”

Koonin implies throughout the book that climate scientists have conspired to downplay uncertainty and exaggerate the risk, apparently unaware that increased uncertainty means increased risks. Nowhere does he mention that climate sensitivity is described in the scientific literature by a probability density function that is highly skewed, with a long high-sensitivity tail that we cannot discount with certainty. Risk is the integrated product of probability and consequences. It’s hard to argue that the consequences of climate change don’t get worse with sensitivity.

If a pilot isn’t sure about having enough fuel to get you to your destination, if an astronomer isn’t sure that an incoming asteroid will miss Earth, if your doctor isn’t sure whether you have a terminal disease, if you’re not sure you turned the stove off: in each of these cases, the uncertainty is unsettling. Why does Koonin think that unsettled questions in climate science are any kind of comfort when the consequences of doing nothing can be catastrophic? Unsettled should leave serious scientists feeling unsettled. (For more information about logical fallacies used by climate change deniers, I recommend www.crankyuncle.com.)

This review appeared originally at Yale Climate Connections, https://yaleclimateconnections.org/2021/05/a-critical-review-of-steven-koonins-unsettled/.