Column: A new study shows how Exxon Mobil downplayed climate change when it knew the problem was real

The crew of a Finnish icebreaker examines sea ice in Canada's Northwest Passage, which has been opening up sooner and for a longer period each summer due to climate change.
(David Goldman / Associated Press)

Big corporations are known for being two-faced — presenting a nurturing, maternal face to the outside world while ruthlessly pursuing profit on the inside.

But few have been charged with as much of a divergence between its outside and inside views as Exxon Mobil, which has been accused of downplaying publicly for decades what its own scientists were saying internally about climate change — that it posed a material threat to the company’s future.

A new study by Geoffrey Supran and Naomi Oreskes, experts in the history of science at Harvard, presents fresh evidence of how great the gap was. The study matches hundreds of Exxon Mobil’s internal reports and peer-reviewed research papers with its advertising — especially paid “advertorials” the company placed in the op-ed section of the New York Times from 1972 through 2001. The authors’ conclusion is that Exxon Mobil systematically “misled non-scientific audiences about climate science.”


It’s pretty clear that their strategy was the same as tobacco’s. Delay looked to them as a smart business choice, and it may well have been.

— Naomi Oreskes, Harvard University

Supran and Oreskes say their work, which was published late Tuesday in the journal Environmental Research Letters, is the first empirical comparison of Exxon Mobil’s internal and peer-reviewed research with its public statements on climate change. Their goal was to address the company position that earlier investigations were based on “cherry-picked” documents.

“We looked at the whole cherry tree,” Supran says, “and the evidence speaks for itself.”

The study may be especially timely now, because a coalition of state attorneys general and the Securities and Exchange Commission are investigating whether the company lied to the public and investors about what it knew about the dangers of climate change. In 2015, New York Atty. Gen. Eric Schneiderman subpoenaed company research on the causes and impact of climate change dating back to 1977, and financial disclosures, public statements and internal reports on the topic dating back to 2005. The company has moved to quash the subpoena.

The study also involves research and public statements issued by the company while Rex Tillerson, the current secretary of state, was a senior executive. Tillerson isn’t mentioned in the paper, but he became a production general manager in 1999, president and a director in 2004, and chairman and chief executive in 2006.

The new study fleshes out previous reporting on the divergence between what Exxon Mobil knew about climate change and the picture it presented for public consumption. The Times, working with the Energy and Environmental Reporting Project at Columbia University’s Graduate School of Journalism, reported in 2015 that the company had invested heavily in research into how climate change could affect a variety of operations in the Arctic, with company scientists using widely accepted climate models that its executives publicly dismissed as unreliable.

At the company’s annual meeting in 1999, The Times reported, then-CEO Lee Raymond denigrated the models underlying the company’s own research as projections “based on completely unproven climate models, or, more often, on sheer speculation.”


In 2005, science writer Chris Mooney documented the company’s years of financial support of individuals and groups fighting policies and government actions to address global warming, typically by instilling doubt about climate science. InsideClimate News in 2015 laid out the discrepancies between Exxon Mobil’s “cutting-edge climate research” and its public stance of climate change denial. Oreskes, co-author of the book “Merchants of Doubt” about the tobacco industry’s decades-long effort to undermine research on smoking’s health effects, that same year showed the similarities between that effort and Exxon Mobil’s campaign of “disinformation, denial and delay.”

“It’s pretty clear that their strategy was the same as tobacco’s,” Oreskes told me this week. “Delay looked to them as a smart business choice, and it may have been.”

The 187 documents examined by Supran and Oreskes included 72 peer-reviewed papers and 36 “advertorials” on the topic. Although the authors largely treat Exxon Mobil as a single company, it’s the product of a 1999 merger between the two oil giants; in most of the period covered by the advertorials, they were placed by Mobil prior to the merger. Tillerson came up through the Exxon ranks prior to the merger.

They ranked each one according to whether its thrust was to acknowledge human activities as a cause of global warming, cast doubt on that conclusion, or reflected both viewpoints. They found that the company’s serious research and internal reporting acknowledged human-caused global warming — as well it would, since corporate decision-making depended on the most accurate possible assessment of the future.


But Exxon Mobil’s public communications, which were geared more toward influencing public policy, projected the opposite view.

Of the company’s internal reports and peer-reviewed papers, more than 80% acknowledged that global warming was real and human-caused. Only 2% expressed doubt, and in those cases the doubt reflected a conventional scientific caution about making categorical findings. Of the advertorials taking a position, however, 81% expressed doubt. Typical, Supran and Oreskes say, was a 1997 advertorial citing a “knowledge gap” in climate science and suggesting that a scientific consensus had not been reached — although by then it had.

Exxon Mobil has responded to the reporting by denying that its scientists reached firm conclusions about climate change that the company hid or suppressed while it was placing skeptical “advertorials” in the press. In a statement issued after the signing of the Paris climate agreement in 2016, the company said it “unequivocally” rejected allegations that it “suppressed climate change research,” and said it understands that “climate change is real.”

Referring to the reporting by InsideClimate News about internal company documents, Exxon Mobil responded that the documents demonstrated “a robust culture of scientific discourse on the causes and risks of climate change.” The company cited more than 100 papers dating from the 1980s that Exxon Mobil scientists either wrote or co-wrote, “with the aim of enhancing the state of the world’s knowledge on the issues surrounding climate.”

Exxon Mobil, in a comment emailed early Wednesday, called the study “inaccurate and preposterous. “ExxonMobil acknowledges the risk of climate change is clear and warrants action,” the company said. It asserted that the study “was paid for, written and published by activists leading a five-year campaign against the company.” Supran and Oreskes, in a financial disclosure statement, said the study was paid for by Harvard University faculty development funds and the Rockefeller Family Fund, and said they have “no other relevant financial ties.”

Supran and Oreskes say it’s accurate, as Exxon Mobil asserts, that the company’s scientists “recognized the developing nature of climate science … [and] mirrored global understanding.” At some points, its scientists even projected more rapid global warming than other experts.


“The question is not whether Exxon Mobil ‘suppressed climate change research,’” Supran and Oreskes write, “but rather how they communicated about it” to a lay audience. Their conclusion is that the company in its marketing and advertising systematically cast doubt on it.

The campaign, they argue, stepped up in advance of the Kyoto protocol on climate change, an international agreement that was reached in December 1997 and currently incorporates commitments by 192 countries. The U.S. has not ratified the protocol.

“Their clear motivation was to undermine Kyoto,” Supran says. In its public statements about the agreement, Exxon Mobil argued that it would bind signatories to financially ruinous policies despite uncertainties about the science. “Let’s not rush to a decision at Kyoto,” urged one advertorial cited by the authors. “Climate change is complex; the science is not conclusive; the economics could be devastating.”

That final phrase may open a window into what Exxon Mobil was thinking in publicly undermining a scientific consensus its own researchers shared: The company may have felt that the short-term economic drag from addressing climate change outweighed the wisdom of accepting scientific fact and joining an international consensus on its consequences.

“With a strategy of delay,” Oreskes says, “they could continue with a very profitable business for another 25 years.”

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6:21 a.m., Aug. 23: This column has been updated with a statement by Exxon Mobil.