The Geography of America’s Carbon Footprint
A recently released a report from the Brookings Institution quantifies the carbon footprint for the nation’s 100 largest metro areas based on fuels used by vehicles (personal and freight) and the energy used in residential buildings.“Shrinking the Carbon Footprint of Metropolitan America” shows that metro areas with ‘high density, compact development and rail transit offer more energy and carbon efficient lifestyles that their sprawling, auto-centric’ counter parts.
The study shows that per capita emissions vary widely by city, depending mostly on the availability of density and rail transit options. So dense areas like New York and Los Angeles actually have smaller footprints per capita than areas like Nashville and Oklahoma City, which are less compact.
Also factoring into footprint size is where the city gets its energy from (coal versus hydropower, for example), the price of that energy (when prices are lower, consumption is higher), and weather (much energy is put into air conditioning and water heating).
As the chart above shows, carbon footprints are much larger in the East and South because of these factors. Hydropower helps areas like the Seattle-Tacoma-Bellevue area keep its carbon footprint small, as do moderate temperatures and high fossil fuel prices.
Compared to other metro areas and the nation in general, Seattle has been greatly decreasing its per capita footprint:
Metropolitan Seattle’s per capita footprint from transportation and residential energy use decreased 4.38 percent between 2000 and 2005. The average per capita footprint of the 100 largest metro areas and of the nation increased 1.1 percent and 2.2 percent during this time, respectively.
The transportation portion of Seattle’s per capita footprint decreased 3.5 percent between 2000 and 2005, compared to an increase of 2.4 percent in the 100 largest metro areas. The residential portion of Seattle’s per capita footprint decreased 7.2 percent between 2000 and 2005, compared to a slight decrease of 0.7 percent in the 100 largest metro areas.
And as far as emissions go, we’re second in the nation for the smallest carbon footprint regarding energy and electricity.
The average Seattle resident emitted 0.356 tons of carbon from residential energy use (rank 2nd). The average 100-metro resident emitted 0.925 tons and the average American emitted 1.16 tons of carbon from residential energy use.
But things start to change once you start to take residential fuels into account:
The average Seattle resident emitted 0.154 tons from electricity (rank 2nd) and 0.202 tons from residential fuels (rank 38th). This compares to 0.611 tons from electricity and 0.314 tons from fuels from the average 100-metro resident.
And then there’s fossil fuel powered transportation:
The average resident in metropolitan Seattle emitted 1.556 tons of carbon from highway transportation and residential energy in 2005 (rank 6th). This compares with 2.24 tons of carbon emitted by the average 100-metro resident and 2.60 tons of carbon emitted by the average American from transportation and residential energy.
The average Seattle resident emitted 1.200 tons of carbon from highway transportation (rank 27th). The average 100-metro resident emitted 1.310 tons and the average American emitted 1.44 tons from highway transportation.
Clearly, taking fossil fuels out of highway transportation would greatly decrease our carbon footprint. The Transportation Choices Coalition has a great one-page PDF that explains some of the recently passed 2008 legislation that might help reduce vehicle miles traveled and build compact and transit-oriented development.
But as the study makes clear, we are going to need some federal government help on these issues to find a way to price carbon emissions, increase investment in energy research and development; establish a national renewable electricity standard; help states reform their electricity regulations; and improve information collection on emissions and energy consumption.
And we couldn’t agree more. In order to shrink our carbon footprint, we’ll need to support and use systems that create density and transportation options, and we'll need the federal government to empower the states to do so.