If Causality is Complicated Enough, You Can Take Credit For Anything
Apparently California has passed a new law that requires land use planning to be tied to the CARB CO2 emissions limits. Well, all of us who make our money in neighboring states will certainly be happy to have yet more Californians driven into our arms.
This effort is based in part on the claim, which I see all the time, from here, based on a Brookings Report here:
Residents of Portland emit 35 percent less carbon per capita than those of other US cities
Portland is the #1 poster child for "smart growth" style urban planning, and so smart growth advocates have decided that Portland's low carbon footprint is due to smart growth.
Interestingly, though Brookings certainly supports smart planning, their study has moments of honesty that everyone tries to ignore. For example, it makes points I have made over and over about the cities at the top of the electrical efficiency and low emissions lists:
The fuel mix used to generate electricity matters in residential footprints. A high-carbon fuels mix significantly penalizes the Ohio Valley and Appalachian regions, which rely heavily on coal power. Alternatively, hydro-reliant metro areas such as Seattle have substantially smaller residential footprints.
Pricing influences the electricity component of the residential footprints. Each of the 10 metro areas with the lowest per capita electricity footprints in 2005 hailed from states with higher-than-average electricity prices, including California, New York, and Hawaii. Many Southeastern metro areas, on the other hand, with high electricity consumption per capita have had historically low electricity rates.
Weather unmistakably plays a role in residential footprints. High-emitting metro areas often concentrate in climates that demand both significant cooling and heating, such as in the eastern mid-latitude states. In contrast, the 10 metro areas with the smallest per capita residential footprints are all located along the West Coast, with its milder climate.
So, let's take Portland. It has a mild climate, it has higher than average utility prices, and its electricity is supplied in large part by zero-emission hydro plants. Small wonder it does well on the footprint analysis. But given all these advantages, supp0rters want to claim Portland is near the top not due to any of this stuff but due to land planning and mass transit? In fact, transit's share of commutes in Portland has been steadily falling for years, despite the urban legends to the contrary.
But here is another reality check on the list -- Portland is #3. #1 on the list is Honolulu, a very mild climate and certainly no poster child for anti-sprawl. Even more telling is #2 - Los Angeles. LA has an even lower carbon footprint than Portland. So much for smart growth and transit ridership as the main explanation!  Even Phoenix, the most spread out non-transit-using city in the country is above average at #21 out of 100, despite having what is most certainly NOT a mild climate.  My guess is that it has something to do with that clean, carbon friendly nuclear power plant just outside of town, the largest in the US.
Postscript: This report claims that smart planning is better than a carbon tax because people don't respond to changes in gas and electricity prices. But the fact that the lowest carbon footprints and lowest per capita electrical use areas correspond with those with the highest prices gives the lie to that proposition.