Green in the City, Brown in the Burbs
Here's a piece by economist Ed Glaeser that's worth a look: "Green Cities, Brown Suburbs." Not surprisingly, cities are greener than suburbs, in terms of CO2 emissions per household. Surprisingly, California metro areas are relatively low emitters: despite the stereotype of gridlocked traffic, aggressive regulations plus temperate climates mean California cities claim the lowest five per-household scores. (The highest five will come as no surprise: Houston, Oklahoma City, Memphis, Dallas, and Atlanta.)
Inter-region, the move to sun is a mixed blessing: some Sun Belt regions are energy efficient, while others guzzle lots of gas and air conditioning. Intra-region, Glaeser notes that environmental efforts to stem new construction are counter-productive, in that they move development from denser, less polluting places to more spread out locations (see chart above). Or, as Glaeser deliciously puts it: "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."