Exxon scientists predicted global warming, even when the company cast doubt, study finds

In the late 1970s, Exxon scientists outfitted one of the company’s supertankers with state-of-the-art equipment to measure carbon dioxide in the ocean and in the air, an early example of the giant’s substantial research. tanker in climate science. change.

A new study published Thursday in the journal Science found that over the next several decades, Exxon scientists made remarkably accurate projections of how much burning fossil fuels would warm the planet. Their projections were as accurate, and sometimes even more so, than those of independent academic and government models.

Yet for years, the oil giant has publicly questioned climate science and warned against any drastic changes to move away from burning fossil fuels, the main driver of climate change. Exxon also ran a public relations program, including ads that ran in The New York Times, that emphasized the uncertainties in scientific research on global warming.

Global warming projections “are based on completely unproven climate models or, more often, pure speculation,” Lee Raymond, chief executive of the newly merged ExxonMobil Corp, said at a company annual meeting in 1999. “Now we do not have a sufficient scientific understanding of climate change to make reasonable predictions and/or justify drastic measures,” he wrote in a company brochure the following year.

In a statement, Exxon did not address the new study directly, but said “those who talk about how ‘Exxon knew’ are wrong in their conclusions,” referring to a slogan by environmental activists who have accused the company of misleading the public about climate science.

“ExxonMobil has a culture of disciplined analysis, planning, accounting and reporting,” the company added, citing a judge in a favorable verdict in New York three years ago, though for a case that addressed the company’s accounting practices, it did not climate science.

The new study, from researchers at Harvard University and the Potsdam Institute for Climate Impact Research, builds on reports showing that, for decades, Exxon scientists had warned their executives about “potentially catastrophic” climate change. caused by man.

The burning of oil, gas and coal is raising the Earth’s temperature and sea level with devastating consequences around the world, including increasingly intense storms, worsening droughts and deadlier wildfires.

Other fossil fuel companies, electric utilities and automakers have come under fire for downplaying the threat of climate change, even as their own scientists warned of its dangers. In recent years, cities, counties and states have filed dozens of lawsuits accusing Exxon and other companies of public deception and demanding billions of dollars in weather damages.

Last year, a House committee questioned oil bosses, including current Exxon CEO Darren Woods, about whether the companies misled the public on the climate. Mr Woods said the positions were “fully consistent” with the scientific consensus at the time.

In the new study, Geoffrey Supran and Naomi Oreskes of Harvard, and Stefan Rahmstorf of the Potsdam Institute, conducted a quantitative analysis of global warming projections made or recorded by Exxon scientists between 1977 and 2003.

Those records, which include internal memos and peer-reviewed articles published with outside academic researchers, constitute the largest public collection of global warming projections on record by a single company, the authors said.

Overall, Exxon’s global warming projections closely tracked subsequent temperature increases of about 0.2 degrees Celsius of global warming per decade, the study found.

The company’s scientists, in fact, ruled out the possibility that human-caused global warming was not occurring, the researchers found.

Exxon scientists also correctly rejected the possibility of an approaching ice age, even as the company continued to refer to it in its public communications; accurately predict when human-caused global warming would be first detected; and estimated how much carbon dioxide could be added to the atmosphere before warming reaches a dangerous threshold, the study found. Some of Exxon’s studies predicted an even steeper rise in temperatures than the planet has experienced.

“We now have indisputable, watertight evidence that ExxonMobil accurately predicted global warming years before it turned and publicly attacked science and climate scientists,” said Dr. Supran. “Our findings show that ExxonMobil’s public denial of climate science contradicted data from its own scientists.”

William D. Collins, who heads the Division of Climate and Ecosystem Sciences at Lawrence Berkeley National Laboratory and who was not involved in the new study, called their analysis “very robust.”

“This is the first paper I’ve seen that is a clear, quantitative comparison of ExxonMobil’s projections with the state of the science in the public domain,” said Dr. Collins, lead author of a chapter on climate projections in a report from 2018. by the Intergovernmental Panel on Climate Change, a body of experts convened by the United Nations.

The new research showed that Exxon’s projections “were very consistent over time,” he said. “They knew all that. They’ve known for decades.”

Edward Garvey, who was hired by Exxon in 1979 to help leading scientists at the time work on its supertanker project, said he was “not surprised that the science was on the money.”

Dr. Garvey and his colleagues installed a dedicated monitoring system on the 500,000-ton supertanker Esso Atlantic to record measurements of carbon dioxide in surface water and air as it traveled from the Gulf of Mexico to the Persian Gulf, an effort by ambitious and novel research. , he said.

The vast amount of data the scientists collected, Dr. Garvey said, pointed to significant increases in carbon dioxide levels in the ocean near the equator, and was later instrumental in understanding the role the ocean played in limiting warming. . At about the same time, Exxon also expanded its research in climate models, hiring leading scientists from academic institutions. But in 1982, when oil markets plunged from excess oil production, Exxon canceled its supertanker project.

“What amazes me is that despite all this knowledge within the company,” said Dr. Garvey, “they continued on the path that they followed.”