27 same global circulation models that Exxon would continue to publicly attack as unreliable for another two decades.24 A Shell Oil researcher made the same admission in an internal report The Greenhouse Effect initially developed in 1986, then formatted for internal publication in 1988 and not unearthed until April of this year. Like Exxon before it, but with greater specificity, Shell recognized that rising sea levels would have “direct operational consequences” for the company’s offshore and coastal facilities, and (implicitly) for others who might be responsible for infrastructure in the same areas. Shell acknowledged that there would be increased but uncertain costs from defending against sea level rise, with the uncertainties compounded by factors like “extreme ocean storms.” (Fig. 11) Fig. 11. 1988—Internal Shell Report The Greenhouse Effect acknowledges unequivocally the rise of global CO2 levels, the primary role of fossil fuel combustion, the ability of oil companies to calculate their own (globally significant) contributions, and clear industry notice of the foreseeable and significant harms from climate change. Unearthed in April by Dutch journalist Jelmer Mommers of De Correspondent, and analyzed in the CIEL report A Crack in the Shell, Shell’s internal study The Greenhouse Effect demonstrates conclusively that sophisticated understanding of climate science and climate risks wasn’t limited to Exxon. More importantly, The Greenhouse Effect provides a detailed snapshot of oil industry knowledge of those risks at a moment when cumulative global CO2 emissions were less than half their current levels. In The Greenhouse Effect, Shell: • Acknowledged unequivocally that atmospheric CO2 levels were increasing; • that fossil fuel combustion was the primary cause: and • that there was “reasonable scientific agreement that increased levels of greenhouse gases would cause a global warming.” • Recognized the potential consequences arising from this warming, including: o Increased water temperatures; o Rising sea levels; o Ocean acidification, with negative impacts on shellfish and corals; o Regional increases in both drought and flood events; Sarah Jerving, et al., What Exxon Knew about Earth’s Melting Arctic, Los Angeles Times, (October 9, 2016). Available online at https:// http://graphics.latimes.com/exxon-arctic/. 24