Hey Mr. Green,
It seems hypocritical for the Sierra Club to voice concern about the environment while promoting air travel to distant destinations. How bad is plane travel? Would traveling by blimp help? Is it ethical?
--Robert in Rochester, New York
Commercial flights make up 9 percent of U.S. transportation-based fuel consumption. But given air travel's effects on the upper atmosphere, its global-warming effects may be far greater. According to the Intergovernmental Panel on Climate Change, aviation's share of U.S. transportation's global-warming effects could be 20 percent, or even 5.5 percent of total U.S. emissions. (Air travel can be very efficient, however. Domestic flights move a passenger 50 miles on a gallon of fuel, compared with 30 miles per person for cars. International flights do even better.)
Read the entire story in Sierra Magazine, originally published on the Sierra Club website (www.sierraclub.org): http://www.sierraclub.org/sierra/2014-4-july-august/green-life/mr-green-tells-us-how-bad-plane-travel