More Options

Climate Science on Trial


Derek C. Araujo

June 3, 2010

Why climate scientists should refuse to engage global warming deniers in public debates.

During the 1980s, evolutionary biologists Richard Dawkins and Stephen Jay Gould famously agreed to abstain from engaging creationists in public debates. They did so because the scientific community had much more to lose than to gain from such spectacles. As Dawkins wrote, “Winning is not what the creationists realistically aspire to.  For them, it is sufficient that the debate happens at all. They need the publicity. We don’t.”

The community of climate scientists would do well to adopt the same policy toward public debates with climate change deniers. Climate change deniers share more in common with creationists than an ideologically driven rejection of well established science. Like creationists, they benefit from the valuable publicity and the patina of respectability that surround public clashes with knowledgeable experts. 

Several days ago I had the sorry experience of attending a debate on the science of global warming at the Cornell Club of New York City. The event did not feature any scientists with specific expertise in the science of climate change. Instead, the debate featured two lawyers representing the Federalist Society, a society of conservative attorneys with a strong pro-business slant, and its left-leaning counterpart, the American Constitution Society.

The resultant spectacle almost made me embarrassed to be a member of the legal profession. It also demonstrated the dangers inherent in jettisoning science’s careful, deliberative pursuit of objective fact in favor of courtroom-style, adversarial combat. This account should serve as an object lesson for any scientist who is invited to debate a global warming denier before an audience of novices.

The moderator of the event, Lois Bloom, a U.S. Magistrate Judge for the Eastern District of New York, began by introducing the two debaters. Francis J. Menton Jr., a partner in the litigation department of the law firm of Willkie, Farr, and Gallagher, argued on behalf of the Federalist Society. Representing the community of climate scientists was Michael B. Gerrard, who is a partner at the New York office of Arnold and Porter, a professor, the director of Columbia Law School’s Center for Climate Change Law, and the author or editor of many books on environmental law.

In terms of actual knowledge and experience relevant to climate science and environmental law, Menton was no match for Gerrard. By Menton’s admission, he has no background or experience remotely related climate science. Rather, he came to the subject as “a newcomer.” In a serious discussion of climate science among knowledgeable parties, this would have put Menton at a severe disadvantage or might have made an in-depth discussion almost useless. His handicap served as no impediment, however, at a courtroom-style contest where rhetorical flair can trump careful and dispassionate reasoning.

Indeed, this is the entire point of debates such as the one sponsored by the Federalist Society. Global warming deniers don’t stand a ghost of a chance when forced to defend their views before knowledgeable experts. With the science against them, their best hope is to change the terms of the debate by subjecting climate science to an adversarial trial before an unknowledgeable public with the frequent nastiness and misdirection that ensues. Menton himself openly advocated rejecting the dispassionate pursuit of objective fact among well-informed experts in favor of a courtroom circus show, with witty cross-examining attorneys acting as ringleaders. In Menton’s words, “laymen can cross examine the scientists, and they don’t have answers to a lot of questions.” The result is to exchange the motto “let the evidence speak for itself” for “may the glibbest man win.”

Menton made all too clear his desire to strip climate scientists of their rightful claim to valuable and specialized knowledge. As he would have it, attorneys, jurors, and laymen without a shred scientific training have perfectly equal claims to determining the cause and likely effects of humanity’s ever-increasing emission of greenhouse gases. As Menton put it to a room full of law students, aged attorneys, and interested members of the public: “Anyone in this room is as qualified to predict the future effects” of global warming as are climate scientists. No PhD? No problem! Let the soccer moms and dads decide.

Once scientists are subjected to the spectacle of a courtroom drama, the mountains of evidence for global warming and against climate change deniers no longer look formidable. Menton’s performance exhibited an impressive array of courtroom theatrics and rhetorical antics, each designed to persuade jurors that they may happily disregard the near-unanimous consensus of tens of thousands of experts who might know something about climate science. To judge by the response of his audience, his assortment of rhetorical ploys answered admirably.

Menton began by summarily dismissing all calculations of the increased temperatures that will result from humanity’s continued consumption of fossil fuels. “That’s not evidence,” Menton explained. “They’re only projections.” Only past measurements are “real.”

Future projections, you see, do not count—that is, unless those projections caution against regulating greenhouse gas emissions. No sooner had Menton utterly discounted climate scientists’ projections than he urged his audience to think carefully about the projected costs of gas and electricity. A twenty percent cut in carbon emissions by 2050, Menton argued, might lead these bills to “double,” “triple,” or increase to “four, or even five times” their current averages. And shouldn’t the public consider this when considering whether to regulate gas emissions?

To Menton’s credit, he rightly admitted that scientists with the relevant expertise have reached a near-unanimous consensus that anthropogenic greenhouse gas emissions are the major driving force behind global warming. Alas, this forced him to do what any skilled courtroom attorney might do in similar circumstances: he smeared climate scientists and impugned the integrity of their data.

Menton would have us believe that the climatologists collect data on global warming much the way the Three Stooges might. As Menton portrayed them, climate scientists are bumbling fools who have enormous difficulty detecting sources of measurement error that are obvious to attorneys and laymen with zero scientific training. Menton recounted stories of climate data measurement stations situated amidst urban areas, where temperatures can be significantly higher than in cooler, rural locals. One photo he displayed showed a cooking grill sitting next to a purported temperature monitoring station. He spoke of regional temperature variations—for example, that between New York City’s Central Park and West Point’s rural New York State campus—that are as large as the recent average global temperature increases measured by climate scientists. He pointed to the widespread use of proxy methods of measuring temperatures before the late nineteenth century, when regular, direct measurement of climate data began.

As one might imagine, climate scientists have long known about the issues Menton highlighted. They have performed their measurements and their analyses very carefully to take into account the obvious variables Menton identified. Even after accounting for these variables, average global temperatures show an unmistakable upward trend. Moreover, it is dead wrong to argue that local variations in temperature make it impossible to accurately measure average global temperature increases. It is as if Menton objected to economists’ declaring a nationwide recession because a few local businesses increased their profits.

Much of Menton’s presentation focused on the famous “hockey stick” graph, a chart from a report by the UN Intergovernmental Panel on Climate Change (IPCC) showing generally stable average global temperatures during the past thousand years, an alarmingly sharp spike in recent decades, and a projection of future temperatures that rockets far above any temperatures we have known.

Menton amused his audience by shrinking the scale on the graph’s vertical axis (i.e., the axis on which temperature is displayed). “Notice that the scale is in tenths of a degree,” he emphasized. He presented a version of the graph with its axis vastly expanded. The data appeared as a tiny line at the bottom of the new graph, its ominous spike reduced to a barely perceptible pimple. Presto! The global warming menace had seemingly disappeared. “Suddenly it doesn’t look so frightening anymore,” Menton joked, as several audience members chortled and nodded approvingly.

No mention, of course, was made of the disastrous effects that would likely follow a long-term increase of global temperatures of only a few degrees Celsius—an increase the science community’s data still predicts, no matter how one stretches the graph’s vertical axis. No matter. These small details were inessential to the thrust of Menton’s presentation.

Menton’s most audacious performance involved his comparison of three graphs showing measured temperature increases since the late nineteenth century. The three graphs were taken from three papers published by the noted climate scientist James Hansen in 1980, 1987, and 2007. All three displayed the same disquieting trend, with average global temperatures rising steadily over the long term despite short-term variations that occasionally dip.

Menton carefully cherry picked and color highlighted two segments of data on a PowerPoint slide, such that the two segments exchanged relative positions in the 2007 graph; where the second segment was higher than the first in the earlier graphs, it appeared underneath the first segment in the last graph. One could imagine him following by asking, “Would you trust a scientist whose data flip-flops like this?”

Such cherry picking is stock-in-trade among global warming deniers’ bag of tricks. Scientists’ measurements of past temperatures have improved significantly over the last thirty years, and it was inevitable that some old data would be cast aside in favor of more accurate figures.

Worse than that, however, was Menton’s comparison of the first two graphs. “Those two segments look a lot closer together in the second graph,” he noted with a flourish. Yet he failed to mention that the vertical scales on the two graphs were different; the second graph’s compressed scale naturally led the two data segments to appear closer. Menton flashed his slide so quickly that few in the audience—including Gerrard—seemed to notice.

The remainder of Menton’s presentation focused on the many specious and long-discredited arguments we have come to expect from global warming deniers: that a period of regional warming during the Medieval era supposedly shows that today’s increase in global temperatures isn’t unusual; that a recent, short-term increase in arctic ice thickness somehow negates the clear, opposing long-term trend; that a handful of stolen e-mails showing scientists discounting unreliable data undermines the data and analysis of tens of thousands of climate researchers corroborating global warming; and that a report by a statistician hired by a Republican Congressman invalidates the IPCC’s “hockey stick” graph despite the graph’s vindication by the National Academy of Sciences and other independent experts.

Mr. Gerrard did a creditable job of answering Menton’s criticisms. He effectively exposed the fallacies of employing short-term trends to discount data on long-term trends and of seizing on regional temperature variations to discredit measurements of overall average temperatures. He laid forth the massive evidence from disparate sources pointing unmistakably to a long-term increase in global temperatures, driven by human-induced greenhouse gas emissions. He pointed out rising sea levels, increases in ocean acidity, and shrinking glacial and polar ice. He explained that even the Pentagon now recognizes global warming, and he recounted the human disasters that will likely follow it that are as serious threats to national security.

Whether Gerrard convinced any audience members to rethink their position is doubtful, however. Many met his presentation with exasperated sighs, apparently having made up their minds about the evidence before setting foot in the room.

During a question and answer period following the debate, a question from the audience nearly left Menton stammering. What plausible alternative explanations, he was asked, account for the obvious warming trend shown in actual temperature measurements since the nineteenth century? Menton’s initial response was ridiculous, consisting of but one word: “Clouds.” After an uncomfortable silence ensued, Menton continued: “Cosmic rays. Nobody knows what’s causing it.”

Lois Bloom, the moderator, asked a very insightful question of Menton. Perhaps a few scientists might be skewing their data; but how is it that independent scientists, employed in different countries and by different agencies, have reached an almost universal consensus that global warming is real? Menton responded feebly that government climate scientists—and in particular, those working for the EPA—have “a monetary stake” in perpetuating alarmist myths about climate change. Menton would have us believe that tens of thousands of scientists from across the globe have perpetrated a near-perfect conspiracy in exchange for pittances often rivaled by public school teachers’ salaries. That most government scientists could earn several times their pay working in industry does not appear to have occurred to him.

Sadly, there was little point to Gerard’s exceptional presentation of the massive evidence pointing to global warming and his patient dissection of Menton’s blunders in reasoning. The great majority of audience members came to the event with foregone conclusions about the global warming “controversy.” The gentlemen seated to my left and right eagerly lapped up Menton’s presentation, guffawing heartily at his humorous jabs at the near-unanimous consensus of knowledgeable experts on climate change.

The evening’s event left me feeling sorry for humanity and increasingly worried for its future. In the end, the two lawyers’ debate was successful only in producing heat—as if the world needed any more of that.

Derek C. Araujo

Derek C. Araujo's photo

Derek C. Araujo is a teaching fellow and Ph.D. candidate at the Columbia University Department of Physics. He is a former Vice President and General Counsel of the Center for Inquiry.