Photo by Rmcgervey

On April 17, 2009, the U.S. Environmental Protection Agency (EPA) formally announced that six key anthropogenic greenhouse gasses endangered public welfare including carbon dioxide, methane, nitrous oxide, hydrofluorocarbons, perfluorocarbons, and sulfur hexafluoride.

The agency reviewed possible environmental and health dangers associated with greenhouse forcing of the climate (global warming) focusing on heat-trapping gasses release by motor vehicles, power plants, and industrial sources. The EPA found, "In both magnitude and probability, climate change is an enormous problem. The greenhouse gases that are responsible for it endanger public health and welfare within the meaning of the Clean Air Act."

Listing associated environmental and health impacts like rising sea levels, ocean acidification caused by increases in atmospheric carbon dioxide, changes in precipitation patterns and associated water shortages, extensive tree die-offs and forest fires, extended heatwaves, and intense precipitation events.

Nearly two years ago the U.S. Supreme Court Ruled that the U.S. Environmental Protection Agency (EPA) has authority under the Clean Air Act (specifically, section 202(a) of the Act) to regulate greenhouse gas emissions from motor vehicles and that the EPA’s denial of a petition to do so was arbitrary and not in accordance with the law.

As apposed to the Bush administration, who opposed invoking its authority to act on global warming, President Obama and his new EPA administrator, Lisa Jackson, prefer congressional action, calling for a new system to let industry cap and trade emissions.

Power generators and motor vehicles account for half of U.S. carbon dioxide emissions. The National Association of Manufacturers said new regulations "will add costly delays to manufacturers seeking to expand operations or upgrade their manufacturing processes in a manner that conserves energy."

The EPA must hold a 60-day public comment period before issuing a final ruling, and will hold two public hearings before finalizing the decision. If Congress does not act, the agency could issue its own regulations.

For more information go to www.PBS.org .