Scientists for ExxonMobil predicted climate change with “shocking skill and accuracy” in the 1970s, according to new research.
Despite this, they continued to cast doubt on climate science and lobby against action on global warming.
Confidential documents and emails, including recent internal messages revealed by a US congressional investigation, have previously shown that the company was aware of the link between fossil fuels and climate change.
But this new study, led by researchers from Harvard University, shows just how accurate Exxon’s own climate modelling was.
“What they understood about climate models thus contradicted what they led the public to believe,” the study’s authors write.
What did ExxonMobil’s scientists predict?
The debate over whether Exxon knew about climate change began in 2015 after leaked internal documents revealed the company’s early knowledge of climate change.
Exxon disagreed with the reports, giving links to internal memos and studies from their own scientists. The company said that interested parties should look at them and make up their own minds.
“That’s exactly what we did,” says lead author of the study Geoffrey Supran.
Researchers analysed more than 100 reports from the years between 1977 and 2014. They narrowed these down to 12 that contained projections for climate change and then compared them to historical observations.
Exxon’s scientists’ projections predicted an average of around 0.2C warming per decade. This is the same as independent academic and government models for climate change.
They accurately dismissed the possibility of an ice age and predicted that global warming would become detectable between 1995 and 2005.
This is the first ever detailed review of the company’s climate modelling data and it reveals that between 63 and 83 per cent of their projections were accurate in predicting global warming.
“What we found is that between 1977 and 2003, excellent scientists within Exxon modelled and predicted global warming with, frankly, shocking skill and accuracy only for the company to then spend the next couple of decades denying that very climate science,” says Supran.
“We now have airtight, unimpeachable evidence that ExxonMobil accurately predicted global warming years before it turned around and publicly attacked climate science and scientists.”
Exxon says this issue has come up several times in recent years and that “those who talk about how ‘Exxon knew’ are wrong in their conclusions.”
It points to a 2019 New York Supreme Court case which claimed the company had engaged in fraud over statements on the costs of climate regulation. The judge ruled that no fraud had been committed and that the company’s executives and employees had acted in good faith.
Which other oil companies knew about climate change?
In the 1980s, many oil companies carried out assessments of how carbon emissions from fossil fuels could impact the planet.
An internal report from 1988 projects that CO2 levels in the atmosphere could double by 2030, sea levels could rise by “five to six meters” and changes in air temperature would “drastically change the way people live and work.”
The report concludes that “these changes may be the greatest in recorded history.”
A public information film from the company also warned of the catastrophic risks of climate change in 1991. Rediscovered in 2017 by Dutch online journalism platform de Correspondent, it contains startling predictions for global warming and sea level rise.
The 28 minute film, titled ‘Climate of Concern’, was originally made for schools and universities. It features warnings about flooding, famine, extreme weather and climate refugees as a result of burning fossil fuels.
These warnings were “endorsed by a uniquely broad consensus of scientists,” the film says.
When the 1988 report was uncovered in 2018, Shell issued a statement saying its “position on climate change [had] been a matter of public record for decades”.
“We strongly support the Paris Agreement and the need for society to transition to a lower carbon future, while also extending the economic and social benefits of energy to everyone.”
But, it added, successfully navigating this “dual challenge” requires policy and cultural change to “drive low-carbon choices for business and consumers”.
Have oil companies acted on climate change predictions?
Public communications from fossil fuel companies over the years have raised doubts about climate science. Exxon itself took out adverts in major publications that suggested climate science was poorly understood.
200 pages of internal documents between lobbyists and Shell, Chevron and ExxonMobil employees were released last year as part of a US congressional investigation into climate disinformation.
They revealed questions about the companies’ own climate commitments and jokes about climate collapse.
Despite Shell pledging to become net zero by 2050, internal PR guidance from 2020 asked employees to frame the goal as “a collective ambition for the world” rather than a “Shell goal or target.”
“Please do not give the impression that Shell is willing to reduce carbon dioxide emissions to levels that do not make business sense,” reads one slide from a PR guidance presentation.
“Shell has no immediate plans to move to a net-zero emissions portfolio over our investment horizon of 10-20 years.”
At Exxon, they promote algae-based biofuels as a key tool in the energy transition. But a leaked presentation from 2018 said that the technology was “[s]till decades away from the scale we need.”
One email from fossil fuel giant BP discussing carbon capture technology said its main goal was to “enable the full use of fossil fuels across the energy transition and beyond.”