In spring 2005, the U.N. convened more than 100 scientists in Oviedo, Spain, to finalize an IPCC special report on carbon capture and storage, a technology that had barely been tested.

With evidence so thin that drafters had warned any broad statement about leakage risk would be "almost meaningless," Canadian physicist David Keith proposed an "expert elicitation": an anonymous survey of what the authors expected future evidence to show.

ProPublica reports the group agreed to keep it off the record — Keith recounted they would "burn it afterward," with no mention in the official report.

Co-chair Sally Benson and senior U.N. official Bert Metz argued informed guesses were better than nothing, and Metz later conceded it was "not the hard science that you would prefer." Five months later, the IPCC published findings that would legitimize CCS for a generation.

The report existed largely because Saudi Arabia and other oil-exporting countries pressured the U.N. to write it despite the paucity of evidence, according to U.N. officials and records cited by ProPublica.

The IPCC, for the first time, invited a large contingent of industry researchers to help write the report; Benson's storage chapter included authors and editors from Shell, Chevron and Saudi Aramco.

This broke from IPCC procedures, which state that reports should assess peer-reviewed literature and that exceptions must be reviewed and clearly cited. Environmental groups and some nations had warned the report would distract from the imperative to phase out fossil fuels.

Industry documents show fossil fuel companies saw CCS as a way to keep burning coal, oil and gas while burying the pollution — internal Exxon documents obtained by Drilled and ProPublica show the company decided in 1988 that climate research it funded should protect the value of its oil, gas and coal.

The Oviedo conclusions had profound, compounding consequences: climate models assumed CCS would work, net-zero pledges assumed it, and governments handed energy companies billions in public funds for "clean coal."

The report stated well-selected storage sites would likely retain 99% of injected carbon for at least 1,000 years, and its summary claimed there were "no major technical or knowledge barriers" — assertions resting entirely on the storage chapter's determinations.

But ProPublica's analysis of an International Energy Agency database finds that since 1996, just 12 large-scale geological storage projects have been built, collectively burying less CO2 than a single power plant emits in a year.

ProPublica reports seven of the 12 have faced technical, financial or performance issues, and U.N. analyses suggest an CCS industry the size of the entire global oil industry would need to exist by 2050 to meet environmental goals.

Enthusiasm for CCS keeps growing even as its record of underperformance mounts.

ProPublica reports that this spring California embarked on one of the world's largest carbon burial endeavors yet, that more than 100 storage-site applications are pending in the U.S. alone, and that President Donald Trump — while cutting most climate programs — has expanded CCS subsidies.

The investigation argues the 2005 report shifted the world's discourse from how to limit carbon pollution to how to remove it afterward, a framing that has allowed fossil fuel production to continue under a climate-solution banner.