Last fall, an expose on extensive research into what Exxon knew regarding the petroleum industry’s impact on climate change was published, including evidence that they conducted extensive research into the issue in the 1970s and 1980s. Their findings resulted in exhaustive efforts to cover up what they had discovered, and to staunch public debate on the subject.

This revelation prompted a criminal investigation against Exxon-Mobil, launched by New York’s Attorney General, with numerous other states following suit shortly thereafter. But a new library of documents that has recently been released pushes the timeline of what Big Oil knew back even further, as this insider knowledge — and its subsequent cover-up — can be traced back to 1968, nearly a half-century ago.

Last April, the Center for International Environmental Law [CIEL] published a treasure trove of oil industry documents that outline the industry’s involvement in climate change research, and this week added a second batch of over one hindered related papers to the library. Some of the notable documents included are a 1957 study that documented the increased amount of carbon dioxide from industrial sources being absorbed by the atmosphere and oceans; a 1968 Stanford Research paper that warned that industrial sources of CO2 were outstripping natural carbon sinks, and that this would eventually result in global warming, large-scale glacial melt, and rapidly-rising ocean levels; and research into carbon scrubber technology that could have been applied to industrial smokestacks to reduce emissions, but was deemed too expensive to be instituted, so it was abandoned.

Research was also done to try to find methods to offset the negative effects of CO2 emissions, such as using other pollutants to reduce rising atmospheric temperatures, and the development of carbon sinks that could scrub CO2 from the air — methods that could allow them to continue to sell their product, while mitigating its harmful effects only after the fact. Further efforts were put into research into alternative theories on the cause of global warming, false theories that are still being used by climate-change deniers today. Finance director for the Institute for Energy Economics and Financial Analysis, Tom Sanzillo, says that there could be legal repercussions for perpetuating this course of action for so long. "There is a clear potential — I would say a high likelihood — of multiple levels of litigation against oil companies," including private lawsuits, government actions, and the prospect of a stockholder revolt that could result from such actions.

“Here’s still more evidence that this industry both understood climate issues [and] had the capacity to cut pollution,” says Carroll Muffett, president of CIEL. “What really emerges from our research is which side of the coin the oil companies decided to pursue.”