Garbage in, Garbage out: Climate Science Group, Government Watchdog Request Correction to National Climate Assessment

Outdated, overblown worst-case scenarios are no way to make public policy.

Today, government watchdog Protect the Public’s Trust (PPT) announced it is urging the Trump administration to fix flaws in the National Climate Assessment (NCA). The NCA informs vast swaths of government policy on climate change but is riddled with questionable science based on faulty assumptions.

President Trump has already moved toward fixing the NCA, which federal law requires be produced every few years. The NCA ostensibly had been the work of the U.S. Global Change Research Program (USGCRP) but critics claimed USGCRP had outsourced much of the work to a consultancy accused of allowing bias to seep into its reports. The Trump administration canceled that firm’s contract for the NCA and the USGCRP websitecurrently contains a banner stating, “The operations and structure of the USGCRP are currently under review.” In addition, the NCA had cited the National Oceanographic and Atmospheric Administration’s (NOAA’s) Billion Dollar Weather and Climate Disasters Project (“Billions Project”). The Billions Project was the subject of a scientific integrity complaint from PPT in 2024. Later that year NOAA said it would investigate the complaint. The Trump administration recently announced that NOAA was no longer updating the Billions Project, effectively scuttling it.

Now, PPT has joined the non-partisan educational foundation CO2 Coalition to request that the White House Office of Science and Technology Policy (OSTP), per the president’s “Restoring Gold Standard Science” executive order, the Information Quality Act (IQA), and Office of Management and Budget’s guidelines, correct NCA 5, released in 2023. NCA 5 is riddled with errors, omissions, and misrepresentations in an apparent attempt to promote Net Zero Theory.

For example, NCA 5 and previous NCAs are marred by the use of Representative Concentration Pathway (RCP) 8.5, an unrealistic and misleading worst-case climate scenario with exaggerated assumptions that the NCA refers to as “business as usual” (essentially doing nothing about climate change). RCP8.5 uses decades old assumptions of carbon dioxide emissions from fossil fuels increasing dramatically for the next 50 or 100 years, an implausible scenario. RCP8.5 projects that there will be a six-fold growth in global coal consumption per capita by 2100. But the International Energy Agency and other energy forecasting groups collectively agree that coal consumption already peaked in 2014.

These criticisms of what CO2 Coalition scientists call a fatal flaw were widespread prior to NCA 5’s publication, so their inclusion appears intended to mislead and deceive the public and policymakers looking for an honest assessment.

There are a number of other glaring problems with NCA 5 and its predecessors, including claims relating to record warm temperatures, wildfire frequency and rising sea levels, and the relationship of CO2 concentrations and temperature, among others. In addition, NCA 5 cited a reliance on “indigenous knowledge” to understand and assess local climate and ecosystems, guide climate adaptation efforts, and leverage “indigenous knowledge” to spur climate action. The use of “indigenous knowledge” in scientific analysis and policymaking has been the subject of past PPT scrutiny.

“I wish the problems the CO2 Coalition and PPT have found in the NCAs could just be shrugged off as either sloppiness or honest mistakes,” said PPT Director Michael Chamberlain. “But that’s simply not possible. The NCA is too influential, and many of the errors are simply too egregious – including the use of discredited sources of data, analysis, and assumptions. Respected experts who care for the integrity of the scientific method above their preferred policy outcomes would never allow such inaccuracies to go unaddressed and simply carry over from version to version. The NCAs must be corrected, and the president should start from scratch.”

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