When it comes to the climate, are cities slicker than suburbs? Researcher Ed Glaeser says yes: city living can substantially reduce your carbon footprint, compared with a home in a distant suburb.
Americans who settle in leafy, low-density suburbs will leave a significantly deeper carbon footprint, it turns out, than Americans who live cheek by jowl in urban towers…When environmentalists resist new construction in their dense but environmentally friendly cities, they inadvertently ensure that it will take place somewhere else—somewhere with higher carbon emissions.
There are at least two ways that urban living reduces CO2 emissions. First, living in a city reduces the consumption of transportation fuels: the closer jobs and stores are to your home, the less you have to drive. Second, if your urban home shares walls, ceilings, or floors with neighbors, you’ll wind up using less energy to heat and cool your home. Glaeser and his research partner, UCLA’s Matthew Kahn, did some heavy number crunching, finding that folks who choose to live in a dense city emit as much as 7 tons less CO2 per household each year than folks who choose a home in the suburbs.
Glaeser makes a second, equally interesting point: living in a place with temperate weather—not too hot, not too cold—or in a place with a clean electricity supply can do wonders for your carbon footprint. So focusing on new urban housing in temperate regions is an especially good strategy for keeping climate-warming emissions in check. (Overall, Portland, Tacoma, and Seattle do a bit better than the national average for personal carbon footprints—see page 41 of this pdf if you want the city-by-city breakdowns.)
I’m a bit annoyed that Glaeser makes what seems like a sweeping critique of “environmentalists” opposing compact neighborhoods; it seems like an unnecessary swipe, since plenty of folks who consider themselves “green” are big supporters of compact cities and transit-oriented development. But despite that hiccup, I think that Glaeser’s done a real service here. It’s an important reminder that living in a a leafy suburb doesn’t necessarily mean you’re living green.