“The European Union voted Tuesday to impose quotas on the emission of carbon dioxide by airlines, setting up a fight with the United States, which argues against unilateral actions on aviation, a relatively small but rapidly growing source of global warming gases.”

“On average, studies have found, a traveler making a typical trip in a plane accounts for roughly the same greenhouse gas emissions as one traveling alone by car — although much depends on the details of any particular trip.

At a conference last month in Washington on global aircraft emissions, Shigenori Hiraoka, a researcher at the Japan International Transport Institute, pointed out that transportation emissions were 14 percent of all greenhouse gas emissions in 2004, but that aviation was just 6 percent of those emissions. That puts emissions from aviation in the range of 1 percent of all emissions. “Aviation’s share is still small,” he said. “Why bother?”

The answer, he said, was that aviation is galloping ahead, with growth of about 4.4 percent a year, overwhelming the fuel economy gains of about 1.3 percent a year. ”

Cutting Jet Fuel Pollution

Somehow I think CO2 emissions from aircraft are only part of the story of their contribution. The fact this is happening at 35,000 feet instead of at road level is not trivial, and CO2 is not all that is being exhausted. I don’t know that we’d ever all want to travel by dirigible to distant lands but there is lots to be done to crank down emissions of all kinds in high speed, high altitude travel.