Advice Goddess Blog
« Previous | Home | Next »

Squawk, Squawk
Oh, the media parrots and their "statistics"; in this case, the oft-repeated claim that airline travel causes more CO2 emissions than driving an SUV. Dave Kopel writes for the Rocky Mountain News:

Actually, typical coast-to-coast commercial air travel may produces vastly less CO2.

Let's stack the deck against air travel: We'll consider United's Los Angeles to New York's JFK service; this involves a relatively older plane, the Boeing 757-200, in a configuration which cuts the 757's normal seating capacity of 182 down to 110. Using United's average 2005 load factor of 81 percent, we have 89 passengers on a typical flight.

Figuring the plane would burn 5,000 gallons of fuel on the trip (probably an overestimate), we get about 56 gallons of jet fuel per passenger.

If you burn 56 gallons of motor fuel in your SUV, assuming 15 highway miles per gallon, then you would drive only 840 miles before using as much fuel as did a passenger in the 2,475 mile LAX to JFK trip.

Jet fuel emits about 8 percent more carbon dioxide per gallon than motor fuel. (EPA, "Inventory of U.S. Greenhouse Gas Emissions and Sinks: 1990-2002" Annex 2, tables 2-17 and 2-24). Even so, the jet is 3.2 times better than the solo SUV for the coast-to-coast trip - even for a flight with an unusually small number of passengers and an older plane. Imagine a newer plane with more passengers, and the environmental superiority of air travel (for long flights) becomes even greater.

Jonathan Tourtellot, the National Geographic Traveler editor who wrote the 2004 article on which Carman had relied, agreed with me that in the particular example above, the commercial flight would be better than the SUV. Because airplanes use so much fuel on takeoff and landing, the average miles per gallon for a long flight will be much better than for a short flight. Tourtellot suggested that the 2004 article might have relied on older data for airline fuel economy, which did not distinguish long flights from shorter flights; the older data might also have been based on the days when there were fewer passengers per plane than today.

It was not unreasonable for Carman to cite National Geographic, nor for National Geographic to use the best data it had available in 2004. Still, because so many people rely on the media for advice about environmentally responsible behavior, it is important to stop the spread of misleading factoids.

via Volokh

Posted by aalkon at July 29, 2007 10:51 AM


Commercial travel is a 'soft target' for the environmental zealots. It's all based upon our need for guilt. Flying should be fun and even if it isn't, it's funny.....

Posted by: Richard Havers at July 29, 2007 7:40 AM

In both cases, there is a factor which has been ignored: when something is made easy and fun, a demand is created which was not there before. The "need" for a vacation involving air travel has been synthesized by Madison Avenue.

A jet engine is wonderfully efficient next to a car's - a reflection of its development by the research teams originally commanded by national military forces. But comparing the "footprint" of each is much like comparing the apartment complex to the group of single-family homes, both of which are sited on formerly pristine estuarine waterfront.

Posted by: Radwaste at July 29, 2007 10:25 AM

Raddy, say that again, I missed something. Comparing these is inappropriate because......?

Posted by: Crid at July 29, 2007 12:12 PM

How do people actually miss the illogic of this argument?

In logic circles, this is known as the Fallacy of Composition. The idea that the whole must have the same properties as its parts, or the idea that the value of an entire collection of items must be the same as one of those items.

In this case, the argument is that since an SUV causes fewer emissions than a passenger jet, it is therefore more environmentally sound to take an SUV from New York to California than it is to fly on a commercial aircraft...quite forgetting the number of SUVs it would take to bring the same number of passengers such a distance as could be brought by a single jet.

Posted by: Patrick at July 29, 2007 2:26 PM

"Raddy, say that again, I missed something. Comparing these is inappropriate because......?"

I see your point. Air travel, just like the ownership of a SUV, is a luxury, but they have radically different alternatives. But the use of either transportation niche ignores the actual problem: the consumption of the natural resources.

Think of it. You're discussing which is the lesser of two evils, but as Patrick pointed out, they're not even in the same league.

We have people selling "carbon credits" already, thinking that this will somehow stop the depletion of oil and the waste of energy - as if people will stop going to WalMart because they are bored!

This is remarkably like the practice of "mitigation". For a while in Florida, you had to "mitigate" the destruction of wildlife habitat by paying the state. A WalMart went in, in my old home town - one of the ecological wonders of the Western Hemisphere, but doomed to support the fat asses of America due to being a barrier island - and the scrub jays' habitat was destroyed. Jays, like all wildlife are manifestly not saved by the obvious pretense of "mitigation", and fossil fuel issues will not be solved by comparing these two mode of travel to each other. Each has to be evaluated against their impacts. That's the tangent I'm on. Sorry for the confusion.

Posted by: Radwaste at July 29, 2007 8:50 PM

Leave a comment