The St. Louis metropolitan area has an outsized carbon footprint, with each resident spewing over 40 percent more into the atmosphere than the average. In the race to the climate change bottom, that ranks St. Louis seventh worst among the nation's 100 largest metropolitan areas.

According to a Brookings Institution report released May 29, the average resident here emitted 3.217 metric tons of carbon in 2005. That came from two major sources: transportation (think tailpipes) and household energy (primarily electricity and natural gas). That's about one more metric ton a year than the national average.

Residential energy use is the largest culprit with St. Louis sixth worst in the country. Between 2000 and 2005, the region's residential energy footprint rose 16.4 percent at a time when the typical metropolitan area experienced a slight decline. Conversely, St. Louis has made progress on transportation emissions during the same five-year period, dropping 3.3 percent while other metropolitan areas collectively increased 2.4 percent.

The report, authored by two Georgia Tech researchers and one Brookings staffer, cites the usual causes: low residential density, reluctance to use public transit, coal-based electricity generation and energy-inefficient homes. High density areas with strong public transit systems have much smaller footprints. St. Louis' per capita emissions are four times larger than New York's, the region with the smallest per capita footprint. Also treading lighter on climate change are cities like Portland and Seattle, which have made the environment a high-priority issue. Their per capita footprints are about one-third the size of St. Louis'.

Click here for the full report, "Shrinking the Carbon Footprint of Metropolitan America.

Terry Jones is a professor of political science at the University of Missouri at St. Louis.