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Calming the Climate Policy Debate

Unsettled: What Climate Science Tells Us,
What It Doesn’t, and Why It Matters
by Steven E. Koonin
BenBella Books, 2021, 316 pages

In a Pew Research Center poll taken in the spring of 2020, 65 percent of Americans said the federal government was doing “too little to reduce effects of climate change.” A few months later, Pew conducted a survey of registered voters on the top issues for the 2020 presidential election. The voters placed climate change a distant eleventh on their list of “very important” issues, behind the economy, health care, violent crime, immigration, economic inequality, and Supreme Court appointments.

These findings may seem contradictory. In fact, they reliably point to a basic though often ignored political truth on climate change. The mass of Americans are not denialists on climate change, but they are also not alarmists. They are asking for bolder policies to combat global warming—but they are not demanding, as are climate activists, an urgent and costly social and economic transformation.

As it happens, Steven E. Koonin’s new book, Unsettled: What Cli­mate Science Tells Us, What It Doesn’t, and Why It Matters, matches the broad sentiments of the public on climate change. Neither an alarm­ist nor a denialist, Koonin is trying to forge a path of reason through an impassioned, sometimes histrionic, debate that threatens to make climate change yet another polarized culture war issue. The task is well worth attempting, especially as what might be called “climate change orthodoxy” is turning into a defining and indeed a defiant stance for Democratic Party elites. The month after his election, Joe Biden called climate change a “national emergency,” and, matching this rhetoric, his admin­istration has proposed spending nearly two trillion dollars to combat this “existential threat to humanity.”

Given these stern pronouncements, Unsettled is bound to be unwel­come in certain political and policy precincts and perhaps seen as heresy. Nevertheless, the book warrants a hearing. Laden with charts, it is not the easiest of reads. Still, I am far from an expert on the climate, a subject that has eluded me in my decades as a professional journalist, and I got through it. Orthodoxies of any type beg for interrogation. What, then, to make of Unsettled? What can the concerned citizen—worried about the health of the planet but not necessarily ready to declare an existential crisis—glean from this book?

The Messenger

One place to begin looking for an answer is with the messenger. In his introduction, Koonin says, “some climate scientists are less than objec­tive when talking to the public” and supports that contention with a quotation from a prominent climate researcher back in 1989:

like most people we’d like to see the world a better place. . . . To do that, we need to get some broad based support, to capture the public’s imagination. . . . So we have to offer up scary scenarios, make simplified, dramatic statements, and make little mention of any doubts we might have.

It is fair enough for Koonin to call our attention to climate scientists as, sometimes, committed political activists, but who is he to be instructing us on this subject?

His credentials certainly sound impressive. A member of the Na­tional Academy of Sciences, Koonin has a BS in physics from Caltech and a PhD in theoretical physics from MIT, and for nearly thirty years he was a professor of theoretical physics at Caltech. He is the author of a 1985 textbook, Computational Physics, on the “methodology for build­ing computer models of complex physical systems,” and has published about two hundred peer-reviewed papers in fields including climate science and energy technology and policy.

For five years, Koonin served as chief scientist at BP—that is, as the top scientist for the multinational behemoth that used to be known as British Petroleum. As he explains this experience, which began in 2004 with his departure from Caltech, his goal was to undertake “a serious study of energy technologies ‘beyond petroleum.’” At a black-tie dinner at Buckingham Palace, he won “an appreciative nod” from the Duke of Edinburgh for a “mini-lecture” on “infrared-active molecules” in the global atmosphere. He left this gilded perch to serve as undersecretary for science in the U.S. Department of Energy in the Obama administration and stayed in that post for two and a half years.

Koonin has been writing about climate science for general-interest publications for years, and these efforts have come under withering fire from peers in the field. In response to Koonin’s 2014 op-ed in the Wall Street Journal on gaps in the knowledge of climate change, Raymond T. Pierrehumbert, a climate physicist currently based at Oxford, wrote in Slate that on the question of the rate of sea level rise, Koonin reached “a conclusion one could draw only through the most shameless cherry-picking.” Slate’s sub-headline branded Koonin a “fresh face of climate inaction.”

It is tempting, then, to wonder whether Koonin embarked on his book project as an effort to settle scores. Yet he does not come across as vengeful in Unsettled. In a return to the sea level dispute, he makes no mention of Pierrehumbert except in an endnote citation of the Slate article. He defends his Wall Street Journal op-ed with an explanation of the method behind his calculations (and tosses in, naturally, three graphs). Unsettled may be an exercise in spirited contrarian thinking, but it is not a polemic. In Koonin’s terms, his book is about supplying calm, informed perspective: “Climate alarmism has come to dominate US politics, especially among Democrats, where I have otherwise long felt most comfortable politically.” At a bare minimum, he says, “any policy should be based upon what the science actually says about the changing climate.”

The Message

As a guide to this disputed territory, Koonin is at his most persuasive when explaining how scientists arrive at their assessments of climate change. In particular, his chapter on climate models is a tour de force. One might think that the availability of supercomputers to crunch enormous amounts of data on the climate would make modeling a fairly routine exercise in which scientists of good faith can largely agree. But that’s not the case. Models are about making predictions of future climate patterns, and scientists assemble models with judgments about factors like cloud formations in the atmosphere. In fact, clouds are crucially important to the models because, as Koonin notes, “depending on their type and formation, clouds will reflect sunlight or intercept heat in varying amounts. . . . This is not at all an unimportant detail, since ordinary fluctuations in the height and coverage of clouds can have as much of an impact on flows of sunlight and heat as do human influences.” And as it turns out, “the greatest uncertainty in climate modeling stems from the treatment of clouds.”

Uncertainty is a key word in Unsettled. Because of uncertainty over key elements like clouds, even the models built by world-class scientists tend to disagree with each other. This is not the fault of the scientists. As one researcher cited by Koonin conceded in a published report on the difficulty of understanding interactions between clouds and the fine particles in the atmosphere known as aerosols, “Cloud-aerosol interactions are on the bleeding edge of our comprehension of how the climate system works, and it’s a challenge to model what we don’t understand. . . . These modelers are pushing the boundaries of human understanding.” Koonin is adept at digging these qualifications out of the scientific litera­ture—testaments to uncertainty that, as he pointedly interjects, tend to be omitted from “popular media.”

He notes, too, that the uncertainty inherent to modeling exercises afflicts not only the methodology behind climate change predictions but also the task of assessing the impact of climate change policies on the climate. Consider the vexing matter of the earth’s reflectivity, measured by the term known as albedo (from the Latin albus, for white). Higher albedo—a greater percentage of sunlight reflected by the earth back into space—could counteract greenhouse gas warming. Imagine, say, making the surface of the land brighter by putting white roofs on buildings. “Geoengineering” of this type could be useful, Koonin says, but he notes that models have trouble evaluating even at a crude level the impact of strategies to increase albedo. He cites a passage in a 2015 report by the National Research Council of the National Academies of Sciences, Engineering and Medicine that acknowledged as much:

The uncertainties in modeling of both climate change and the consequences of albedo modification make it impossible today to provide reliable, quantitative statements about relative risks, consequences, and benefits of albedo modification to the Earth system as a whole, let alone benefits and risks to specific regions of the planet.

No open-minded reader can digest this sentence and not have doubts about the general state of our climate science knowledge. A primary goal of Unsettled is to establish uncertainty as a basic principle of climate science and policy, and in that important objective, the book succeeds.

Unsettled, though, is more ambitious than that. Koonin also aims to persuade us to reject dire assessments of climate change and public policies tailored to those assessments. He starts by taking pains to separate himself from climate-change denialists. “Yes, it’s true that the globe is warming,” he notes—the “surest indication” of this trend is “the growing ocean heat content”—and it is also true that “humans are exert­ing a warming influence” on the planet. This acknowledgment given, he proceeds to the crux of the debate: “the real question is not whether the globe has warmed recently, but rather to what extent this warming is caused by humans.”

His answer, tendered in the chapter called “Humble Human Influ­ences,” is not to the extent you have been led to believe by climate doomsayers. He concedes that there is “no doubt” that a long-standing and continuing rise in the concentration of carbon dioxide in the atmosphere, “is, and has been, due to human activities, primarily the burning of fossil fuels.” And as the amount of carbon dioxide “contin­ues to increase, the atmosphere’s heat-intercepting ability (and hence its warming influence) will also increase. . . .” He also concedes that, before 1950, human influences on the climate “were less than one-fifth of what they are today.” The nearly planetwide economic boom after the Second World War—in North America, Europe, and Asia—led to the burn­ing of much greater quantities of coal and oil.

Yet this is not the whole story. Water vapor, which occurs naturally in the atmosphere, also is a greenhouse gas, Koonin notes, and “it accounts for more than 90 percent of the atmosphere’s ability to intercept heat.” The planet naturally heats up by absorbing sunlight energy, and all told, Koonin concludes, human influences on the climate “currently amount to only 1 percent of the energy that flows through the climate system.”

In his discussion of human influences on the climate, Koonin is generally good at pointing out how they may be occurring. He doesn’t seem to be hiding anything. Sometimes, though, he seems to put his finger on the scale in playing down the human factor. For example, on the matter of decreased rainfall and higher temperatures making for conditions apt to promote forest fires in the western United States, he cites a 2018 scientific report attributing “increased forest fire in North America to anthropogenic climate change during 1984–2015” to a pat­tern that is caused or influenced by humans. As a result, his citation continued, “the western US forest fire area” over this period has nearly doubled “compared to what would have been expected in the absence of climate change.” That sounds worrisome. But Koonin quickly pivots to the possibility that human influences which have nothing to do with climate change—such as forest-management practices—also could be significantly contributing to the mounting problem of forest fires. They might be, but in this particular passage, Koonin sounds less like an agnostic scientist guided by the evidence and more like a lawyer invested in a brief.

Muddled Responses

Koonin’s downplaying of human influence on the climate leads, unsurprisingly, to a caution against “forced and urgent decarbonization” measures. It makes more sense, he says, to pursue “only low-risk changes until we have a better understanding of why the climate is changing, and how it might change in the future.” He also thinks that America’s democratic system, with changing Congresses and presidents, may be incapable of sustaining “dramatic changes” in greenhouse gas emissions policies over any length of time. But his scrutiny of bold ideas for action, even those with widespread support in political, economic, and scientific circles, is inadequate. Consider a tax on carbon, an idea derived from the basic principle of microeconomics which holds that more of a product—any product, including carbon discharges—will be made if the producer is able to create the good without having to pay for its “external” social costs. “A carbon tax offers the most cost-effective lever to reduce carbon emissions at the scale and speed that is necessary,” a group of economists, including twenty-eight Nobel laureates, four former chairs of the Federal Reserve, and fifteen former chairs of the Council for Economic Advisors, declared in a statement originally published in the Wall Street Journal in 2019. “By correcting a well-known market failure, a carbon tax will send a powerful price signal that harnesses the invisible hand of the marketplace to steer economic actors towards a low-carbon future.”

A related idea for setting a price on carbon is to create a market in which emitters would trade permits for the right to release carbon diox­ide. Koonin notes that “because oil packs a lot more energy per carbon atom than does coal,” an economy-wide carbon price would affect quite differently the buyer of gasoline at the pump and the operator of a coal-fired power plant. But his critique of a carbon price doesn’t extend beyond this point. Perhaps he feels outside of his ken on economic-policy matters—“I am a physicist, not an economist,” he takes care to remind us at the outset of the book—but economic policy is at the forefront of the climate change debate and always will be. The European Union is currently developing a plan to tax imported goods—to apply a carbon tariff, in effect—based on the amount of greenhouse gases emitted to produce them. Koonin should be more conversant in such consequential proposals.

With rapid and broad-scale decarbonization measures frowned upon, Koonin puts forth the considerably more modest alternative of “adapta­tion to a changing climate.” Humans, he notes, “have been successfully adapting to changes in climate for millennia,” sometimes “without the foggiest notion” of the cause of the changes and sometimes, as in the case of the Dutch and their system of dikes, with a well-conceived strategy of alleviating anticipated hazards. “Adaptation,” he points out, “is naturally tailored to the different needs and priorities of different populations and locations. This also makes it more politically feasible,” he suggests, as “local adaptation does not require the global consensus, commitment, and coordination that have proved so far elusive in mitigation efforts.” Just as California has put into place stiffer building design codes to minimize the damage caused by earthquakes—“we can’t stop [earthquakes],” Koonin notes—regions can undertake projects like flood control for local rivers to lessen anticipated harms caused by climate change.

Yet Koonin is cautious even in the presentation of this alternative, at first asserting that adaptation is what he thinks “will be our primary response” and only in the book’s penultimate page explicitly calling for the pursuit of adaptation strategies “more vigorously.” He can’t quite decide, it seems, whether he wants to confine his role to expert diagnostician of our climate condition (where he clearly feels on strongest ground) or to join the crowded ranks, including credentialed experts and lay persons alike, of the prescribers. To borrow the term he uses to describe climate models, this approach can feel muddled.

Against Alarmism

Of course, one can accept Koonin’s wisdom on the inescapable uncer­tainties of climate science and still reject his conclusion that the climate “crisis” is something a good deal less than that. In a sense, this approach would be in keeping with Koonin’s own message, for repeatedly in the book he encourages the ordinary citizen to become an amateur climate science expert—to read firsthand scientific evaluations, to study with a self-trained eye the sorts of graphs he presents in Unsettled. This is a noble aim: it harkens to the venerable American idea, as old as Jefferson, that democracy best works and maybe only can work with an informed citizenry. Otherwise, the complicated issues are left to the experts, and the experts, operating as a kind of priesthood, can betray or mislead us.

Climate science, though, strains the capacity of the informed citizen to make wise assessments, as do any of the physical sciences (try learn­ing quantum mechanics). In the social sciences, the experts are not as daunting. An economist can examine the data on whether increased unemployment benefits are keeping people from taking jobs and venture a conclusion on the matter. An ordinary citizen can make a reasonable appraisal, too, based not on close study of the data, but on knowledge of labor conditions in his or her community and a judgement, gained from life experience, on human nature. Life experience, though, is of no help on climate science. I can observe that sea waters are rising on Cape Cod, where I now live, with higher tides than I am accustomed to seeing, but I would need to invest some serious time in scientific study to be able to reach a defensible conclusion on the reason why this is happening.

Still, the ordinary citizen should not feel at the mercy of climate experts armed with impenetrable knowledge. Here Koonin is prescriptively helpful. Toward the end of Unsettled, he recounts an episode from 2019 when Chuck Schumer of New York, as the Democratic leader of the U.S. Senate, introduced a bill “to prohibit the use of funds to Federal agencies to establish a panel, task force, advisory committee, or other effort to challenge the scientific consensus on climate change.” The idea was to thwart climate-change denialists in the Trump administration from overturning established scientific facts. The legislation went nowhere. Nevertheless, as Koonin notes—though with a touch of the exaggeration he faults climate-change “alarmists” for indulging—this impulse to squelch cross-examination of a supposed consensus is il­liberal and has unhappy precedents: “I found the bill uncomfortably reminiscent of a 1546 decree by the Council of Trent that attempted to suppress challenges to Church doctrine.”

On the time-honored principle that an adversarial process, as in a courtroom, can advance truth, he recommends the creation of a “Red Team” of experts (no partisan designation is meant by Red) as a “qualified adversarial group” charged with the mission of “rigorously questioning” published climate assessment reports. This seems altogether sensible and the ordinary citizen—the voter—can encourage the Schumers of Capitol Hill to accept a Red Team as a tool for advancing the climate change debate.

But is the Democratic elite prepared to listen to what ordinary Americans have to say on climate change? At the moment, the party is insufficiently mindful that some voters whose support it needs, espe­cially in the working class, are likely to rebel at an abrupt implementation of an agenda that will raise costs for gasoline and eliminate jobs in fossil fuel extraction industries. In the Pew poll of voters on their top issues in the 2020 presidential election, only 42 percent cited climate change as “very important” to their vote, compared to 79 percent for the economy and 68 percent for health care. So notwithstanding the view from policy-activist quarters, and notwithstanding his own declaration, Biden did not enter office with an urgent mandate from voters on climate. Democrats need to consider a more moderate approach in keeping with public sentiments, if only to forestall a rupture that would benefit Republicans, who remain largely opposed to any meaningful action on the issue.

In the end, climate change poses the question of whether Americans and especially their elected representatives are capable of having a reasoned exchange on an emotive issue—such as has eluded the nation on other such matters ranging from mask mandates to abortion, voting rights, and police reform. It is tempting to conclude that a respectful discourse on climate change is impossible in today’s acrimonious circumstances. But that verdict seems too bleak. After all, even with its flaws, Unsettled points to how this debate can be conducted.

This article originally appeared in American Affairs Volume V, Number 4 (Winter 2021): 110–18.

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