It's all in how you want to look at it.
The Center for Neighborhood Technology has a recent study that gives the traditional antagonists -- suburbanites and city dwellers -- something for either side when the subject is the environment.
If you're in the suburbs, you can point to the comparatively low amount of greenhouse gas emissions per acre (red is worst, light yellow is least):
Or if you're in the city you can point to the comparatively low amount of greenhouse gas emissions per household:
You can play with the maps and compare regions here.
Personally, I prefer per capita data, because that gives large families a chance to claim responsible emissions and allows us to pretend that population growth isn't an issue.
It makes sense to use per acre data only if you actually limit population, say, to match any greenhouse emission reduction targets. Was it 80% reduction by 2050?
Come to think of it, that might not be such a good idea after all.
Bob - when this is a regional/national/global problem, I'm not sure I'm excited about you riling up old antagonisms, even in jest. When every person in the MPR listening region (and much further) needs to use as much less as possible, bickering about whose fault it is won't help much.
I don't think this gives the suburbanites much to brag about. All it proves is that not only is suburban living wasting space, it also wastes energy and creates more greenhouse gasses.
The first map proves the point that there are less people per acre in the suburbs. The second map proves that they burn more stuff. Suburban living is still quite a bit more wasteful than urban living.
I don't think the environment cares about greenhouse gas per capita... it cares about per acre. (If we assume the environment has feelings, and frankly, I think we must.)
The environment does not care about emissions per acre. It does not care about emissions per household. It cares about total system-wide emissions of CO2. The city produces opportunities to reduce carbon, but does not necessarily produce results. I don't know what the point of this exercise is, except for finger-pointing. I can not imagine the suburbs suddenly being abondoned. Let's concentrate on reducing everyone's emissions, and implementing policies that encourage greater population density in the long run by improving the cities so people have no desire to run away from them.
While we're on the subject: Would it lower emissions if we turned off all of the air conditioning?
"While we're on the subject: Would it lower emissions if we turned off all of the air conditioning?"
Generally, yes. Exceptions: people who's power comes from solar, wind, nuke or hydro sources.