Researchers warned American Petroleum Institute in 1968 that the release of carbon dioxide from fossil fuels could lead to ‘worldwide environmental changes’

The oil industry’s knowledge of dangerous climate change stretches back to the 1960s, with unearthed documents showing that it was warned of “serious worldwide environmental changes” more than 45 years ago.



The Stanford Research Institute presented a report to the American Petroleum Institute (API) in 1968 that warned the release of carbon dioxide from burning fossil fuels could carry an array of harmful consequences for the planet.

The emergence of this stark advice follows a series of revelations that the fossil fuel industry was aware of climate change for decades, only to publicly deny its scientific basis.

“Significant temperature changes are almost certain to occur by the year 2000 and these could bring about climatic change,” the 1968 Stanford report, found and republished by the Center for International Environmental Law, states. “If the Earth’s temperature increases significantly, a number of events might be expected to occur including the melting of the Antarctic ice cap, a rise in sea levels, warming of the oceans and an increase in photosynthesis.

“It is clear that we are unsure as to what our long-lived pollutants are doing to our environment; however, there seems to be no doubt that the potential damage to our environment could be severe.”

The study, written by scientists Elmer Robinson and RC Robbins, adds that accumulation of CO 2 in the atmosphere could cause “serious worldwide environmental changes”.

The scientists estimated that CO 2 in the atmosphere could reach 400 parts per million by 2000. In fact, CO 2 levels broke that milestone last year, recording their largest leap on record.

This huge increase in CO 2 , the primary driver of the greenhouse effect, has helped global temperatures rise by 1C over the past century. It is estimated that about three-quarters of the world’s known fossil fuel reserves, including oil, coal and gas, will have to remain unburned if civilisation is to avoid the worst ravages of climate change, such as droughts, floods, food insecurity and inundation from rising seas.

API, the peak body for the oil industry in the US, knew about the dangers of climate change at least 20 years before the issue was brought into mainstream public discourse via the former Nasa scientist James Hansen. Former US president Lyndon Johnson also received an early warning about climate change, with scientists explaining the mechanism of the greenhouse effect in 1965.

Last year, it was revealed that ExxonMobil, the world’s largest oil company, knew of climate change as early as 1981, only to spend millions of dollars over the following 27 years to promote climate denial. The exposure of this prior knowledge has been led by Inside Climate News.

Exxon had a dedicated in-house team that established the connection between fossil fuels and climate change, but the company still spent years refusing to acknowledge the issue and funding climate denial activities. Exxon now insists it accepts climate science and doesn’t promote denial of the changes to the planet already under way.

The Center for International Environmental Law (CIEL) said hundreds of documents show oil and gas executives met in 1946 to agree that they should fund research into air pollution issues. The subsequent findings were then covered up to protect company profits, according to the environmental law group.

Carroll Muffett, president of CIEL, said the latest documents from 1968 “add to the growing body of evidence that the oil industry worked to actively undermine public confidence in climate science and in the need for climate action even as its own knowledge of climate risks was growing.

“These documents are the tip of an evidentiary iceberg that demands further investigation,” Muffett said. “Oil companies had an early opportunity to acknowledge climate science and climate risks, and to enable consumers to make informed choices. They chose a different path. The public deserves to know why.”

The prominent climate scientist Michael Mann, of Pennsylvania State University, said it was “disgraceful that industry groups like API knowingly hid the dangers of their project decades ago when they first learned of them, much as the tobacco industry hid the dangers of their product”.

API was contacted for comment on the documents.