In a report issued by the Brookings Institution on May 29, 2008 ranking major US metropolitan areas by transportation and residential energy carbon emissions, the New York City metro area (including metro Long Island and New Jersey) came in fourth on the list, with each of us bearing responsibility for an average of 1.5 metric tons of carbon emissions each year.

As is so often the case with environmental studies like this, densely-populated, urban areas in temperate climates with good mass transit did substantially better than hot cities dominated by auto-intensive suburban sprawl and large, energy-inefficient single-story, single-family homes. NYC was beat out by Portland (1.45 per capita tons), Los Angeles (1.41 per capita tons) and Honolulu (1.36 per capita tons).

Bringing up the bottom of the list were the usual red/purple state subjects, including Lexington (KY), Indianapolis, Cincinatti, Toledo, Louisville and Nashville. But lest we expend too much self-righteousness on our conservative brethren, some bastions of liberalism didn't do much better: #55 Austin (2.57 per capita tons), #69 Baltimore (2.71 per capita tons), and #81 Madison, WI (2.91 per capita tons).

Each person in #100 Lexington is responsible for an average of 3.46 metric tons of carbon emissions each year, more than twice the average New Yorker. To their credit, the Lexington Herald-Leader covered the report, cited three principal factors:

• Traffic. The sprawl of the metropolitan area leads to a lot of driving, and there is relatively little use of public transportation. Single-family homes in a Lexington subdivision use considerably more energy than, say, Baltimore rowhouses that have shared walls. Also counting against us: All the truck and other traffic on the interstate highways that intersect here.
• High consumption of dirty energy. Lexington's hot summers and cold winters mean residents use furnaces or air conditioners almost year-round. And much of that energy comes from burning coal, a high-carbon fuel.
• Inefficient homes. Because we are used to some of the nation's cheapest electricity, building standards in Kentucky and the Southeast place minimal importance on energy efficiency. Oregon, Washington and Idaho also have relatively cheap energy, but have "a conservation ethic" that means they waste less of it, Brown said.

A city such as Los Angeles ranked well, she said, because much of its development is in a concentrated area, there are strict building standards and many people use a mass-transit rail system.