The climate coverup began nearly half a century ago...

In 1968, a pair of scientists from Stanford Research Institute wrote a report for the American Petroleum Institute, a trade association for America’s oil and natural gas industry. They warned that “man is now engaged in a vast geophysical experiment with his environment, the earth” — one that “may be the cause of serious world-wide environmental changes.”

The scientists went on: “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.”

That 48-year-old report, which accurately foreshadowed what’s now happening, is among a trove of public documents uncovered and released Wednesday by the Washington-based Center for International Environmental Law. Taken together, documents that the organization has assembled show that oil executives were well aware of the serious climate risks associated with carbon dioxide emissions decades earlier than previously documented — and they covered it up.

That research, CIEL says, was used to “promote public skepticism of environmental science and environmental regulations the industry considered hasty, costly, and potentially unnecessary.”

Muffett said in a statement that the documents “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.”

Last year, InsideClimate News revealed that top executives at Exxon knew about the role of fossil fuels in global warming as early as 1977, then lobbied against efforts to cut greenhouse gas emissions. In January, the New York attorney general announced an investigation into ExxonMobil over allegations that it lied to the public and its investors about climate change.

A report that surfaced in February revealed the American Petroleum Institute knew about climate change in the early 1980s.

The industry group did not respond to HuffPost’s requests for comment Wednesday.

CIEL’s new documents, however, show that the cover-up has endured for a generation or more.