Wednesday, October 6, 2010

A Game of Numbers

The concept behind David Owen's Green Metropolis is simple: the most environmentally sound areas are not the suburbs where people work hard to be "green," but the massive cities where there is no choice but to be. Despite seeming counter intuitive, the reasoning is persuasive. Cities force people to make do with less stuff and less space. Since parking is generally a tragic experience, many will do away with their cars and rely on public transportation, biking, or walking. Apartments are smaller, therefore requiring less energy to live in. So on and so forth.

One way he gets to this conclusion is by using all the stats that show the difference in pollution between cities and suburbs. Let's say Generic City releases X amount of pollution which is considerably higher than the Y amount of pollution that Generic Suburb releases. Normally people would look at that and say, "eww gross, Generic City is disgusting." However, Owen uses pollution per capita to make his point. So if there are a million people in Generic City and 250,000 in Generic Suburb, it turns out that the suburbanities produce more pollution per person than the urbanites. Even if Generic City is an overall toxic place to live, each person is responsible for only a tiny amount of that toxic environment which makes them "greener" than your average home owner with the compost pile and hybrid car packed with reusable grocery bags. Vindication! You hear that hazy brown air, pea soup looking water supply, and cement covered land? City folk are good for the environment. In your face sustainable landscaped homes! Eat that backyard farmers!

On paper this is fine. In reality there is an obvious problem. Small amounts of pollution multiplied by a million people on a small footprint (not the carbon type) often creates an extremely polluted environment. In the end it doesn't matter how little each person contributes to a cesspool... it's still a cesspool.

This is all, of course, a simplification. His argument is far more detailed than what I've written above. But instead of being persuaded, I realized instead the beautifully tricky nature of proving anything with statistics. Statistics are the used car salesmen of science. They might be telling the truth, but the truth they tell is a selective and sidestepping sort of truth. The type of truth that tells you "this thing runs like a beauty" when the tires are flat. I'm not saying that city living isn't greener, his points make sense on that. I'm just saying it's a little hard to get too smug about it when I have to purify my tap water and step over trash on every street.
posted by jw