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.
Erin
I frequently see these kinds of comparisons between the impacts of city and suburban lifestyles. What I never see is the inclusion of truly rural living.As someone who lives in a tiny Alaskan town, I wonder how rural living stacks up? On the one hand, there’s nowhere more than a few miles even possible to drive here, and much of the heating is done with wood. (With a small enough population, standing dead trees can be harvested sustainably for everyone’s firewood). On the other hand, basically every consumer good that comes here has to be shipped a long way. We have very sustainable very local fish and meat, but our oranges come from thousands of miles away… I’d really be curious to see someone include us rural folks in one of these analyses some day.
Matt the Engineer
Such an analysis would be quite interesting. On one hand, it’s likely that having little access to goods and services means that you consume less. On the other, fuel sources like dead wood only really work for small populations – if everyone lived in rural communities there wouldn’t be enough wood, and we’d need to bulldoze a lot of nature to build homes. Playing this scenario out, perhaps the size of the footprint of one’s house is more important than the house’s location. Another important factor would be commute – rural works for ranchers and poets, but not so well for construction workers and lawyers.
Tim
I’m troubled by the author’s implication that having a lower carbon footprint means a perosn is more ethical. For example, are people who live in Seattle and can take advantage of the mostly clean electricity more ethical than those who live in Wyoming and get their electricity from coal? Or, by extension, do we want everyone moving to places with clean electricity (e.g., Seattle, Tacoma, Portland) so that they can take advantage of the cleaner electricity? We should be careful before assigning personal ethical value to things that are to some degree outside of an individual’s control.
Matt the Engineer
“Are people who live in Seattle and can take advantage of the mostly clean electricity more ethical than those who live in Wyoming and get their electricity from coal?”If they moved there for that reason, then yes. Even if not, Wyoming voters could have pushed for sustainable energy rather than settle for cheap coal. “Or, by extension, do we want everyone moving to places with clean electricity…”I’d say so. If we put real costs on our resource use then this will solve itself. If coal power was priced appropriately, then areas with clean energy will be less expensive places to live. If too many people move to Settle and we can’t provide clean energy for all of them (thereby pulling coal power from elsewhere), electricity rates will go up here to balance this out. But of course as coal power prices go up it will make more sense everywhere to invest in sustainable energy sources, so this effect might be quite small.
Joe
The author Glaeser concludes: “Thoreau was wrong. Living in the country is not the right way to care for the Earth. The best thing that we can do for the planet is build more skyscrapers.”So, the article seems mistitled. Instead it should be called something like “Houses Are Not As Good As Skyscrapers.” That seems reasonable, if not a bit obvious.I live in the suburbs and use my bike for most of my transportation including work, groceries, etc. My home is well insulated, has mostly native plants in yard, etc. I don’t believe that I am inferior to a city dweller who is living in a large house using their car for everything. So the first criteria is perhaps single-dwelling or dense-dwelling (e.g. skyscraper). The second criteria depends on your environmental lifestyle.
Erin
Continuing my rural vs. urban/suburban thoughts. Clearly there’s not enough land/firewood, etc. for everyone to live in very rural places. I’m simply wondering if those of us who do have on average a bigger or smaller footprint than folks in more populated places. I don’t think commuting’s an issue—I’d almost define “rural” as too far away to commute to anywhere. Certainly no one in my town commutes in the traditional sense (no one can afford to pay $100 round trip airfare every day and we don’t have roads). Some work outside of town, but it’s usually either fishing, seasonal work, or 2-week on 2-week off industrial work in a distant camp (those have their own issues, but aren’t quite “commuting”).People here also live commonly in quite small homes compared to other places—materials are expensive to transport, and folks have often built their own places (my family of 3 lives in a 450 sq foot yurt). I think the impact of travel and shipping would be the big negatives, but it’s hard to quantify those. I’d particularly need to know the impact of small plane (like 5 seat cessna) travel.
Matt the Engineer
That’s easy enough. Grabbing some random data from the Internet, a C-172 can fly 580 nm (667 miles) at 80% power on 56 gallons of fuel. That’s 11.9 miles per gallon, and less when you consider fuel for takeoff and landing. So it’s certainly no Prius, and I’m guessing you have to fly quite a ways. Plus a Prius would likely carry more weight than a Cessna. So yes, bringing in materials will probably be your weak point.