NAS Report Reaffirms Greenhouse Gas Threat as Trump Administration Seeks Rollback

On September 17, 2025, the National Academy of Sciences (NAS) released a report titled "Effects of Human-Caused Greenhouse Gas Emissions on U.S. Climate, Health, and Welfare," reaffirming the Environmental Protection Agency's (EPA) 2009 endangerment finding that identified greenhouse gas emissions as a threat to public health and welfare. The NAS report emphasizes that scientific evidence supporting this finding has only strengthened over time, highlighting increased extreme temperatures, rising sea levels, and intensified extreme weather events.

This release comes in response to the Trump administration's proposal in July 2025 to revoke the 2009 endangerment finding, a move that could lead to the rollback of various environmental regulations. The NAS's report serves as a direct rebuttal to this proposal, underscoring the consensus within the scientific community regarding the human-induced nature of climate change and its detrimental effects on public health and the environment.

Key Findings of the NAS Report

The NAS report presents several critical conclusions:

1. Human-Caused Emissions and Climate Change: Emissions of greenhouse gases from human activities are increasing atmospheric concentrations, leading to unequivocal warming of Earth's surface and changes in climate.

2. Health Impacts: Climate change intensifies risks to human health in the United States, including increased exposure to extreme heat, air pollution, and climate-sensitive infectious diseases.

3. Welfare Impacts: Climate-driven changes negatively affect agriculture, water resources, and infrastructure, leading to economic and social challenges.

4. Future Projections: Continued greenhouse gas emissions will lead to more severe climate changes, with the severity increasing with every ton of emissions.

Trump Administration's Proposal to Revoke the 2009 Endangerment Finding

In July 2025, the Trump administration, under EPA Administrator Lee Zeldin, announced plans to overturn the 2009 endangerment finding. This finding had been a cornerstone for regulating greenhouse gas emissions under the Clean Air Act. The administration's proposal argues that the EPA will regulate pollutants only if they cause direct, localized harm and a clear cause-effect relationship can be demonstrated.

Critics argue that this effort lacks scientific and legal merit and could severely undermine future climate action. Environmentalists and legal experts see the endangerment finding as scientifically rigorous, and overturning it would limit future regulatory authority on emissions. While supporters hail the move as economic liberation, legal challenges are inevitable. The EPA must still open the policy for 45 days of public comment, and the case is likely to reach the Supreme Court. However, changes in the Court’s composition since 2007 may favor the administration’s position.

Legal Challenges and Transparency Issues

A federal judge ruled that a secretive climate change panel, assembled by the Trump administration to support its rollback of greenhouse gas regulations, is not exempt from the Federal Advisory Committee Act (FACA), which mandates transparency in government advisory committees. The panel, formed in March 2025 by Energy Secretary Chris Wright, was composed of climate change skeptics and produced a report used by the EPA to justify reversing the 2009 endangerment finding. Environmental groups sued, claiming the Climate Working Group operated illegally in secret. Judge William Young agreed, finding the group's work constituted advice and recommendations, not mere information exchange, as the administration argued.

Political and Societal Implications

Over 100 Democratic lawmakers in the U.S. House of Representatives have called on the Trump administration to abandon a proposal to repeal vehicle emission standards. In a letter led by Representative Doris Matsui and signed by notable figures including Alexandria Ocasio-Cortez and Jerrold Nadler, the lawmakers urged the EPA to maintain greenhouse gas regulations for light-, medium-, and heavy-duty vehicles. They warned that repealing these standards would harm the clean vehicle industry, cost thousands of American jobs, and hinder U.S. competitiveness against countries like China.

Conclusion

The NAS report underscores the growing body of scientific evidence linking human-caused greenhouse gas emissions to adverse effects on climate, health, and welfare. As the Trump administration moves to revoke the 2009 endangerment finding, the report serves as a critical reminder of the importance of evidence-based policy decisions in addressing climate change. The coming months are likely to see intensified debates and legal battles over the future of U.S. environmental regulations and the nation's commitment to combating climate change.