The U.S. Environmental Protection Agency (EPA) denied 10 petitions challenging its 2009 determination that climate change is real, is occurring due to emissions of greenhouse gases from human activities, and threatens human health and the environment.

The petitions claimed that climate science cannot be trusted, and assert a conspiracy that invalidates 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 what it describes as months of serious consideration of the petitions and of the state of climate change science, the EPA says it found no evidence to support the petition claims. In contrast, the EPA says its review shows that climate science is credible, compelling, and growing stronger.

The basic assertions by the petitioners and EPA responses follow.

Claim: Petitioners say that emails disclosed from the University of East Anglia’s Climatic Research Unit provide evidence of a conspiracy to manipulate global temperature data.
Response: EPA reviewed every e-mail and found this was simply a candid discussion of scientists working through issues that arise in compiling and presenting large complex data sets. Four other independent reviews came to similar conclusions.

Claim: Petitioners say that errors in the IPCC Fourth Assessment Report call the entire body of work into question.
Response: Of the alleged errors, EPA confirmed only two in a 3,000 page report. The first pertains to the rate of Himalayan glacier melt and second to the percentage of the Netherlands below sea level. IPCC issued correction statements for both of these errors. The errors have no bearing on Administrator Jackson’s decision. None of the errors undermines the basic facts that the climate is changing in ways that threaten our health and welfare.

Claim: Petitioners say that because certain studies were not included in the IPCC Fourth Assessment Report, the IPCC itself is biased and cannot be trusted as a source of reliable information.
Response: These claims are incorrect. In fact, the studies in question were included in the IPCC report, which provided a comprehensive and balanced discussion of climate science.

Claim: Petitioners say that new scientific studies refute evidence supporting the Endangerment Finding.
Response: Petitioners misinterpreted the results of these studies. Contrary to their claims, many of the papers they submit as evidence are consistent with EPA’s Finding. Other studies submitted by the petitioners were based on unsound methodologies. Detailed discussion of these issues may be found in volume one of the response to petition documents, on EPA’s website.

For information on EPA’s findings and the petitions, click here.

For more information on climate change, click here.

To review America’s Climate Choices report, click here.

To review State of the Climate report, click here.

To review information on Indicators of Climate Change, click here.