US EPA publishes final endangerment finding for greenhouse gases

7 December 2009

The US Environmental Protection Agency (EPA) signed today two findings regarding greenhouse gases (GHGs): (1) the endangerment finding which states that GHGs threaten the public health and welfare of the American people, and (2) the cause or contribute finding which states that GHG emissions from new motor vehicles and new motor vehicle engines contribute to that threat. Signing of the findings by the EPA coincides with the beginning of the UN climate conference in Copenhagen.

GHGs are the primary driver of climate change, which can lead to hotter, longer heat waves that threaten the health of the sick, poor or elderly; increases in ground-level ozone pollution linked to asthma and other respiratory illnesses; as well as other threats to the health and welfare of Americans, said the EPA.

EPA’s final findings respond to the 2007 US Supreme Court decision that GHGs fit within the Clean Air Act definition of air pollutants. The findings themselves do not impose any emission reduction requirements but are a necessary legal condition for the US EPA that allows the agency to regulate GHG emissions. Once the endangerment finding and the cause or contribute finding have been adopted, the EPA is in the position to finalize the GHG standards proposed earlier this year for new light-duty vehicles as part of the joint rulemaking with the Department of Transportation.

EPA’s endangerment finding covers emissions of six key greenhouse gases—carbon dioxide (CO₂), methane (CH₄), nitrous oxide (N₂O), hydrofluorocarbons (HFCs), perfluorocarbons (PFCs), and sulfur hexafluoride (SF₆).

Scientific consensus shows that as a result of human activities, GHG concentrations in the atmosphere are at record high levels, noted the EPA. Data shows that the Earth has been warming over the past 100 years, with the steepest increase in warming in recent decades. The evidence of human-induced climate change goes beyond observed increases in average surface temperatures; it includes melting ice in the Arctic, melting glaciers around the world, increasing ocean temperatures, rising sea levels, acidification of the oceans due to excess carbon dioxide, changing precipitation patterns, and changing patterns of ecosystems and wildlife.

President Obama and Administrator Jackson have publicly stated that they support a legislative solution to the problem of climate change and Congress’ efforts to pass comprehensive climate legislation. EPA issued the proposed findings in April 2009 and held a 60-day public comment period. The agency received more than 380,000 comments, which were reviewed and considered during the development of the final findings.

Source: US EPA