For context, the big oil firms did a series of internal studies back in the late 1970s and early 1980s which accurately anticipated the rise in atmospheric CO2 concentrations and global warming that would result, but went and hired the tobacco-cancer denial machine instead of looking for ways to move the world off fossil fuels.
That’s the most recent piece of a big chunk of documents which have come out during earlier lawsuits over the past ten or twelve years. The Drilled Podcast has been chronicling the whole thing in detail.
Paywall-bypass to the WSJ article that The Guardian is describing