Exxon 'knew about climate change 40 years ago', report claims

Oil giant Exxon knew about the negative effects of climate change as early as 1977, 11 years before it became a mainstream political issue, a recent investigation has claimed.

Exxon, now Exxon-Mobil and the largest oil and gas company in the world, also spent millions of dollars funding misinformation campaigns in the intervening decades, Inside Climate News reported.

Reporters spent months interviewing former employees and analysing internal documents to conclude that in the 1970s and 1980s, Exxon spent more than $1million funding cutting-edge research into climate models and carbon dioxide absorption methods.

They found that in July 1977, Exxon's senior scientist James Black told the company's management committee:

There is general scientific agreement that the most likely manner in which mankind is influencing the global climate is through carbon dioxide release from the burning of fossil fuels... present thinking holds that man has a time window of five to 10 years before the need for hard decisions regarding changes in energy strategies might become critical.

And yet 11 years later, when evidence on global warming was presented to a congressional hearing in 1988, Exxon's public position was that climate change science still wasn't conclusive.

Inside Climate News and Greenpeace allege that Exxon have spent more than than $30million on think tanks that promote climate denial to date.

The Union of Concerned Scientists released a investigation last year which found that fossil fuel companies' communications strategy was:

Victory will be achieved when the average person is uncertain about climate science.

A spokesperson for Exxon told Scientific American:

We didn’t reach those conclusions, nor did we try to bury it like they suggest...These guys go down and pull some documents that we made available publicly in the archives and portray them as some kind of bombshell whistle-blower exposé because of the loaded language and the selective use of materials.

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