Tuesday, August 7, 2007

Rise of the environment-killing pedestrian zombies

Why are most of my blog posts just repostings of letters I wrote to the forums at Salon.com? Maybe because I expect that someone will actually read. Or maybe it's because I need a fire lit under my butt before I produce anything I consider worth reading.

Today's kindling is brought to you by "leading environmentalist" Chris Goodall, author of How to Live a Low-Carbon Life and foremost proponent of the new and evil "driving is more eco-friendly than walking" meme. I attached this lengthy letter to Andrew Leonard's skeptical analysis of the claim.

Goodall's basic claim is that, if you have to choose between walking to a grocery store 1.5 miles away and driving the same distance, the food needed to replenish the burned calories has a bigger greenhouse gas impact than the gasoline burned.

There are obvious problems with this research (beyond the fact that his book's website breathlessly announces this conclusion as "new research", without mentioning that the research is entirely his own). First, and most suspicious, he assumes that all the calories come from factory-farmed beef, which has enormous environmental impact when compared to eating lower off the food chain. The other factor which severely undermines his conclusions is this: once a person decides on a car trip, it becomes very easy to travel further. Rather than the three miles in Goodall's calculations, they might go ten miles to take advantage of the two for one sale at a competing grocer, or a few more miles to go to multiple grocers, or another dozen miles to Costco to stock up on soy milk (guilty as charged).

There are other, less pressing inaccuracies, some of which actually help his case. He forgets that starting up a cold engine for a short trip uses more gas than a car's MPG rating would indicate. He also ignores cycling as an option (cycling burns about half as many calories per mile as walking). He forgets that you would burn more calories walking back, because you're carrying a lot of groceries. He seems to have made a mistake converting from miles to kilometers. A three mile walk should burn 300 calories, not 180. 180 is more likely from a three kilometer walk.

This crappy, back-of-the-napkin calculation doesn't warrant near the publicity it's receiving; it certainly shouldn't drive anyone's lifestyle changes. When I first heard of this, I (like Andrew Leonard) assumed that the calculation was just hyperbole designed to show how woefully inefficient our industrialized food production is. But reading Goodall's own "research", he mentions replacing walking with driving as the environmentally friendly option, not replacing that slab of factory-farmed steak with some peaches from the local farmer's market[1]. Sure, towards the end he makes a wistful comment about "reduc[ing] the greenhouse gas intensity of our foodstuffs." But it is supremely irresponsible for anyone who touts himself as a "carbon-reduction guru" to make "walk less, drive more" his only concrete suggestion.

Elsewhere, he has compared carbon credits to medieval indulgences[2], and has been commissioned by the Times of London to do a "carbon audit" of Prince Charles (a celebrity climate change crusader, somewhat akin to Al Gore on this side of the pond). Such behavior makes me suspect that the damage Gooding is doing to environmentalism is due to malice, not incompetence.


After a timely e-mailed response from Mr. Goodall, and a deeper perusal of lowcarbonlife.net, the author strikes me as sincerely committed to helping people reduce their environmental impact. I still worry that, on this particular issue, he's framing the story in a disastrous way, and a lot of people are going to take the message the wrong way. But I think his book has a lot of timely information, and it will be good for everybody if it sells well.


[1] In several places in Gooding's report, he goes to great lengths to equate factory-farmed meat to all foodstuffs. Elsewhere, he calls ruminant-based food production "particularly damaging".

[2] I don't trust carbon credits yet, but I do believe that with better science, more auditing, and international agreements to give them more standing, they're going to become a key part of the fight.

Wednesday, August 1, 2007

From Salon: We're all going to die!

Malthus fascinates me. When someone mentions him, I have to chime in. Reposted from here for anyone who doesn't want to click on the link:

I'm in the "Malthus was right" camp. To me, the lack of a population crash thus far isn't evidence against his theory. Let me explain.

Malthus was certainly right in the trivial sense: exponential population growth cannot continue forever. But was he wrong for failing to predict the rise of the industrial agriculture and chemical fertilizers that have managed to feed our exponential growth? No. These developments didn't negate Malthus' theories. In fact, these discoveries may have worsened their eventual consequences.

Humans didn't find a brand new way to permanently increase our food supply. Instead, we started a straightforward oil for food program, where we pumped oil and natural gas from the ground, changed it into fertilizer and pesticide, and sprayed it all over the planet to increase our harvests. It's akin to the difference between getting a better job and finding a pile of money under a rock.

As a non-renewable resource, oil is a terrible basis for population growth. Once it runs out, the population supported by oil will need to either change their food source or shrink until it comes back in line with what the Earth can sustainably produce. If the supply of oil drops too suddenly, you end up with six or seven billion people living on a planet that can only really support a billion, all looking for their next meal.

Having that temporary infusion of resources has allowed humanity to far exceed the numbers that the planet can legitimately support. Malthus predicted that as we reached the limits of growth, there would be increasing downward pressure on the population, to the point that we could never overshoot carrying capacity by much. What he didn't foresee was a situation where the population didn't just reach the limits of subsistence, but rocketed past them, making the consequences of the eventual crash far more calamitous.

That's why I was a bit rankled by this post. Malthus' "limits of subsistence" are defined by the amounts that humans need in order to survive. It seems possible to reduce population growth by allowing each individual to consume far, far more resources than survival dictates. But whether the increased demands on resources come from our increasing numbers or our increasing consumption per capita, we're still putting ever greater stress on the planet's ability to sustain us.

Solving the population problem by bringing everyone up to a First World standard of living is a non-starter. The planet cannot keep up with the demands for resources humanity currently places on it. We need to scale back resource usage by either cutting back on people or resources used per capita.