Behind the Curve

Photo by Matt D'Annunzio

Prof. Josh Howe explores the paradoxical history of global warming.

By Chris Lydgate ’90
Josh Howe

In 1957, a young meteorologist named Charles Keeling placed instruments in California, Antarctica, and Hawaii to perform what was then considered an obscure measurement—the concentration of carbon dioxide in the earth’s atmosphere. Since then, the Keeling Curve has become one of the most iconic images in the history of science. It represents seasonal undulations in the atmosphere as plants in the northern hemisphere absorb and release CO2. It represents global warming, industrialization, and the accumulation of scientific knowledge. 

It also represents a tragedy.

That is the thesis of Prof. Josh Howe [environmental studies & history 2012–] in Behind the Curve, which examines the history of climate change from Keeling’s first tentative conclusions to President Obama’s second inaugural address.

Stripped to its essentials, Howe’s argument is that the debate over global warming has become a tragedy in the Aristotelian sense. Because the warming is taking place over the course of decades, it cannot be readily detected by the ordinary person; for this reason, we must rely on scientific measurement and interpretation, which means we must rely on scientists. Unfortunately, scientists, by and large, are profoundly uneasy in their role as advocates. Instead, they typically call for more research to fill in the uncertainties, assuming that more information will automatically lead to rational decisionmaking—a belief Howe, quoting one of his historical actors, refers to as the “forcing function of knowledge.”

Behind the Curve demonstrates convincingly that this faith is misplaced—after 50 years, we have more knowledge about the effects of CO2 on global warming than ever, yet the curve keeps climbing. Compounding the tragedy, however, he also shows that the insistence of scientists (and environmentalists) on the primacy of science in the debate over global warming has given their opponents an easy target: science itself.


Sitting in his office on the fourth floor of Eliot Hall, which looks across the parapet to the Great Lawn, Howe has pursued an unlikely road to becoming an environmental historian. Growing up in Boise, Idaho, his early hopes of becoming a professional skier were cut short by an accident on Mount Bachelor that shattered his right leg in several places. After getting a BA from Middlebury College in history and creative writing, he worked as a freelance sports journalist, an English teacher, a photographer, and a ski coach, before going to Stanford to pursue a PhD in history.

Howe had intended to specialize in 17th-century French agriculture until a stultifying three-hour lecture on 16th-century coin-collecting nearly made him quit grad school. “I began to realize I’d been barking up the wrong tree,” he says. “I was really interested in political history.” Before long, he was poking around the filing cabinets of Stanford climatologist Stephen Schneider, who encouraged him to investigate the history of global warming.

The theory that industrialization—and its reliance on burning fossil fuels—might drive up the world’s temperature was first proposed in 1938 by a British steam engineer named Guy Callendar. But the first solid evidence didn’t emerge until 1957, when oceanographer Roger Revelle and physicist Hans Suess published a paper documenting an increase in atmospheric CO2. “Human beings are now carrying out a large scale geophysical experiment of a kind that could not have happened in the past nor be reproduced in the future,” they concluded. Howe argues that the modern science of climatology was born in the Cold War, amid hysteria over Sputnik, anxiety about nuclear annihilation, and the possibility, both tantalizing and terrifying, that humans might learn how to control the weather.

Page after page, Behind the Curve demonstrates the profound tension between science and politics—or more accurately, the anxiety among scientists that their credibility would be torpedoed if they allowed themselves to be lured from the safe harbor of factual inquiry into the treacherous shoals of politics. Fundamentally, as Howe states, “The scientists believed that more and better science would inform appropriate policy discussions, in which they did not need to take sides.”

Through the ’70s and ’80s, the impact of rising CO2 became more and more clear. Scientists amassed reams of data to document the planet’s warming trend, but the only political goal they achieved was to win funding for further study. In 1976, Stephen Schneider published The Genesis Strategy, sounding a call to arms in the face of looming climate catastrophe. The book became a cause célèbre and landed Schneider an appearance on the Tonight Show with Johnny Carson. Among the scientific establishment, however, Schneider faced anger and resentment for straying from the doctrine of impartiality and nearly lost his job at the National Center for Atmospheric Research.

As the evidence mounted for the catastrophic effects of global warming, some scientists made their warnings starker. In 1981, NASA scientist James Hansen published the results of a new atmospheric model (dubbed Model II) that predicted the effects of higher CO2 levels, including the collapse of the West Antarctic Ice Sheet and a rise in the sea level of up to six meters—enough, as Hansen wrote, “to flood 25% of Florida and Louisiana, 10% of New Jersey, and many other lowlands throughout the world.”

As head of the Goddard Institute for Space Studies, Hansen’s prestige was unimpeachable. But as a government scientist, he was also vulnerable—the Reagan Administration simply cut off his funding. Hansen’s predicament reflected a brutal dilemma. Simply stockpiling knowledge about global warming had little effect on the political sphere. But if you entered into that sphere and became an advocate, you risked your prestige—and your position.

In response, scientists believed that if they could speak with a unified voice—a consensus—they could reduce their political exposure and amplify their influence. But scientific consensus turned out to be a conceptual Frankenstein that would haunt the debate over global warming for decades. All it took was a couple of dissenting voices to shatter the perception of unity. “As both environmentalists and anti-tobacco advocates learned during the 1970s and 1980s, destroying consensus by manufacturing doubt was easier than forging even an overwhelming majority of agreement, let alone a unanimous viewpoint,” Howe writes.

It is, of course, far too early to tell how this tragedy will be resolved. But by examining the role scientists have played in the climate debate, Howe provides fascinating insight into the uneasy interplay among science and politics. It also brings to mind Cassius’ words in another epic tragedy. “The fault, dear Brutus, is not in our stars, but in ourselves.”