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  Co2 comparison articles

  I disapprove of the way this article, and many others, are written. Two things specifically annoy me, first is the confusion about the primitive unit of co2 production, and the second concerns using unrigorous, untransparent physics, with difficult to interpret numerical terms.

  Concerning my first issue, consider the following:

  "I can further tell you that the Boeing 737-300 that United flies on
  its Philadelphia-Boston route holds around 128 passengers, so if the
  plane were full (wedding crashers!), the total emissions would be a
  bit higher."

  Obviously the plane will emit only slightly more CO2 with another 28 people onboard - in fact it will emit far less CO2 per person. Why does the author take the per person carbon as the primitive, when obviously you can only get per person carbon by dividing out of a single total carbon emission - that of the entire plane. It is in no way true that the plane produces X kg of carbon because each person contributes their little amount. Rather, the plane produces X and because we like to calculate everything, we attribute X/N where N is the number of paying passengers on the plane KG to each passenger.

  Concerning my second worry, what is 0.3442 kgCO2/mile? Certainly a number from some website somewhere, but how do I know it in any way connects with reality? I suppose if its about 2.3 kg from 1 liter,
  that means they are calculating for 6.7 miles to the liter, which is
  25 miles to the gallon. There are not very many "mid sized cars" built
  today which get 25mpg on the highway. I'll give you five dollars if you can find one rated so poorly on fuel economy.gov which qualifies as "mid size". I turned that figure exactly on
  the trip to portland, which was not all highway, and which had 6
  people and luggage in a 20 year old, full size car.

  Aside from these two issues, the conclusion is bonkers: "Per person, this journey
  isn't dramatically different from a carbon angle, with the 100 cars
  coming out slightly ahead."

  Slightly ahead? 10 000kg versus 18 000kg? How is that slightly ahead?
  Also, the cars were all packed with organic footons, try to get those
  on  the plane!

  Another thing, it's not the same to release co2 at ground level versus tens of
  thousands of feet in the air. Also, for your not flying to make a
  difference, you have to fly enough less that flights get canceled, and
  that means people lose jobs (which for some reason upsets people). Also, planes put a lot of water in the air, which forms clouds, and might be responsible for global cooling.

  It is, however, absurd to do these calculations at all - it relies on individual desire to save the world to, save the world. People cannot, and should not, be expected to do this. Put a price on carbon, and then people will be green by just trying to save money. On Umbra on driving versus flying posted 1 year, 4 months ago 10 Responses