In addition to driving Hummers instead of Priuses, real environmentalists drive short distances instead of walking.
I ask because I came across an interesting challenge to the notion that taking short trips in a car is bad for the planet. This challenge comes from Chris Goodall, the author of “How to Live A Low-Carbon Life.” Mr. Goodall is a member of the Green Party in Britain and a devout environmentalist — he says he has ceased air travel because of its emissions. But he also questions how much good is being done by eliminating short trips by car. In fact, he says that in some circumstances it’s better to drive than to walk. ...If you walk 1.5 miles, Mr. Goodall calculates, and replace those calories by drinking about a cup of milk, the greenhouse emissions connected with that milk (like methane from the dairy farm and carbon dioxide from the delivery truck) are just about equal to the emissions from a typical car making the same trip. And if there were two of you making the trip, then the car would definitely be the more planet-friendly way to go.
And yes, that includes the amortized carbon "footprint" of the car manufacturing and food production processes.
Presumably this implies that walking across the country produces far more carbon dioxide than flying across the country.
(HT: Megan McArdle.)
That's fascinating.
I'll have to read the calculation when I have more time, but to get an idea of the scale of the claims I did a couple of back of the envelope calculations.
Cows are notorious methane producers, clearly milk was chosen for that reason, rather than say eggs or carrots. A single typical dairy cow can produce 17 gallons per day or roughly 270 cups.
OTOH the average American car has a quoted (ie, maybe you'd get that with a warm engine and with no traffic, not the typical short run) fuel efficiency of 24.7mpg, so 3/2 mile is 0.06 gallons.
So according to the story, the methane from one dairy cow is equivalent to 270*0.06 = 16 gallons of petrol or a 400 mile trip in a car.
Assuming the cow's methane is the dominant factor. If it works out this way because the average glass of milk is driven 400 miles in a lorry or something, then obviously this is less surprising. If that's the case, then there is clearly scope for food-related emissions to be reduced.
Also, methane supposedly causes 25 times as much warming as CO2.
Chris Goodall, quoted at http://www.off-grid.net/2007/08/09/how-to-live-a-low-carbon-life/:
“Food is more important [to Britain’s greenhouse emissions] than aircraft but there is no publicity,” he said. “Associated British Foods isn’t being questioned by MPs about energy.
“We need to become accustomed to the idea that our food production systems are equally damaging. As the man from Ryanair says, cows generate more emissions than aircraft. Unfortunately, perhaps, he is right. Of course, this doesn’t mean we should always choose to use air or car travel instead of walking. It means we need urgently to work out how to reduce the greenhouse gas intensity of our foodstuffs.”
Simply cutting out beef, or even meat, however, would be too modest a change. The food industry is estimated to be responsible for a sixth of an individual’s carbon emissions, and Britain may be the worst culprit.
“This is not just about flying your beans from Kenya in the winter,” Mr Goodall said. “The whole system is stuffed with energy and nitrous oxide emissions. The UK is probably the worst country in the world for this.
“We have industrialised our food production. We use an enormous amount of processed food, like ready meals, compared to most countries. Three quarters of supermarkets’ energy is to refrigerate and freeze food prepared elsewhere.
A chilled ready meal is a perfect example of where the energy is wasted. You make the meal, then use an enormous amount of energy to chill it and keep it chilled through warehousing and storage.”
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Clearly his article (which I haven't been able to find!) has been hijacked by people who want to make a flippant point about cars.
He seems remarkably non-rabid, actually. Had a quick look at his blog, it seems pretty thorough. (eg. he prefers off-shore wind to domestic PV cells, which is eminently sensible for the UK climate imo.) Check out his blog post on zero-carbon homes, I was astonished at the upcoming regulations that are going to be imposed here.