Carbon dioxide is a threat to public health, according to the US Environmental Protection Agency (EPA).
The agency's new stance would appear to pave the way for much tougher controls on greenhouse gas emissions. It concluded, "greenhouse gases contribute to air pollution that may endanger public health or welfare," after a two-year review conducted on the orders of the US Supreme Court. "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."
Carbon intensity cut for Japan
The Federation of Electric Power Companies of Japan (FEPC) announced aims on 19 April to reduce the carbon intensity of its power production by one third.
Last year, 0.45 kg of carbon dioxide was produced for each kWh of power. By 2020, FEPC wants this figure to be 0.33 kg. It proposes to do this by boosting non-fossil and nuclear generation to meet 50% of supply. Nuclear power currently provides about 30% of Japanese electricity.
The announcement is part of FEPC's contribution to the International Energy Partnership of similar utility bodies from around the developed world. The IEP has recognised nuclear power as a "key part of the solution to both climate change and energy security."
Because greenhouse gases are now said to be a threat in line with the Clean Air Act, the EPA could move in future to control their emission. However, a 60-day public comment period must follow the announcement, made on 17 April, and the EPA would only set new legislation after "an appropriate process" and considering "stakeholder input."
"This finding confirms that greenhouse gas pollution is a serious problem now and for future generations," said EPA head Lisa Jackson. She added that, "Fortunately, it follows President Barack Obama's call for a low carbon economy and strong leadership in Congress on clean energy and climate legislation."
The EPA considered six greenhouse gases in its analysis: carbon dioxide, methane, nitrous oxide, hydrofluorocarbons, perfluorocarbons and sulfur hexafluoride. The origin of the study was a Supreme Court decision in April 2007 that greenhouse gases were air pollutants under the Clean Air Act after a challenge to the EPA from the state of Massachusetts over the role that car emissions play in public health.