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Greenhouse Gas Emissions

Denial of Petitions for Reconsideration of the Endangerment and Cause or Contribute Findings for Greenhouse Gases under Section 202(a) of the Clean Air Act

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Action

EPA determined in December 2009 that climate change caused by emissions of greenhouse gases threatens the public's health and the environment. Since then, EPA received ten petitions challenging this determination. On July 29, 2010, EPA denied these petitions.

The petitions to reconsider EPA's "Endangerment Finding" claimed that climate science can't be trusted, and asserted a conspiracy that calls into question the findings of the Intergovernmental Panel on Climate Change (IPCC), the U.S. National Academy of Sciences, and the U.S. Global Change Research Program. After months of serious consideration of the petitions and of the state of climate change science, EPA found no evidence to support these claims.

The scientific evidence supporting EPA's finding is robust, voluminous, and compelling. Climate change is happening now, and humans are contributing to it. Multiple lines of evidence show a global warming trend over the past 100 years. Beyond this, melting ice in the Arctic, melting glaciers around the world, increasing ocean temperatures, rising sea levels, altered precipitation patterns, and shifting patterns of ecosystems and wildlife habitats all confirm that our climate is changing.

Response to Petitions

​Resources

Scientific Assessment Reports

Recent inquiries and investigations of the CRU emails and IPCC

Recent investigations and inquiries into the emails by other organizations have all resulted in clearing the scientists of alleged wrong-doing.

Petitions

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