Wednesday, December 05, 2007

Groups & Governments Petition For Action On Aviation Emissions

Dec 5: A coalition of environmental groups, states and regional governments filed petitions with the U.S. EPA urging the Agency to address the effects of vast amounts of global warming pollution from the world's aircraft fleet. The petitions are the first step in a process that requires the EPA to evaluate the current impacts of aircraft emissions, seek public comment and develop rules to reduce aircraft emissions or explain why it will not act. Earthjustice, the public interest environmental firm, filed the environmental groups' petition on behalf of Friends of the Earth, Oceana and the Center for Biological Diversity. Also filing petitions are the States of California, Connecticut, New Jersey and New Mexico and the District of Columbia through their Attorneys General, the Commonwealth of Pennsylvania through its Department of Environmental Protection, the City of New York through its Corporation Counsel, and the South Coast Air Quality Management District through its District Counsel.

According to a release from Earthjustice, aircraft emit huge amounts of carbon dioxide. They currently account for 12 percent of carbon dioxide emissions from U.S. transportation sources and three percent of the United States' total carbon dioxide (CO2) emissions. The U.S. is responsible for nearly half of worldwide carbon dioxide emissions from aircraft. Aircraft also emit nitrogen oxides, known as NOx, which contribute to the formation of ozone, another greenhouse gas (GHG). Emissions of NOx at high altitudes result in greater concentrations of ozone than ground-level emissions. Aircraft also emit water vapor at high altitude that forms condensation trails or "contrails." Contrails are visible cloud lines that form in cold, humid atmospheres and contribute to the warming impacts of aircraft emissions. Moreover, the persistent formation of contrails is associated with increased cirrus cloud cover, which also warms the Earth's surface.

The release indicates that together, these high altitude emissions have a greater global warming impact than if the emissions were released at ground-level. A recent report by the UK Royal Commission on Environmental Protection found that the net effects of ozone, contrail and aviation-induced cloud cover is likely to triple the warming effect of aircraft-emitted CO2 alone. The report concludes that if these estimates are correct and the anticipated growth in aviation realized, aviation may be responsible for between six and ten percent of the human impact on climate by the year 2050.

The petition filed asks EPA to respond within 180 days and initiate a formal process to limit and reduce greenhouse gas emissions from all U.S. certified aircraft and all foreign aircraft arriving in or departing from U.S. airports, which the groups say it could do by: Adopting operational measures to minimize fuel use and reduce emissions from aircraft; Requiring the use of lighter, more aerodynamic, and more energy efficient airplanes, as well as the development of even more efficient designs; and Adopting regulatory measures to create incentives for the use of cleaner jet fuels.


Access a release from Earthjustice with links to additional information including key aviation and global warming resources cited in the petition (click here). Access the petition filed by environmental groups (click here). Access a release from California Attorney General Edmund Brown Jr. and link to the states' petition (click here). [*Climate, *Air]