"By most significant measures," David Owen argues in his new book Green Metropolis, "New York [City] is the greenest community in the United States."

(Dramatic pause.)

"The most devastating damage that humans have done to the environment has arisen from the burning of fossil fuels, a category in which New Yorkers are practically prehistoric by comparison with other Americans, including people who live in rural areas or in such putatively eco-friendly cities as Portland, Oregon."

Come again? "Putatively eco-friendly"? Maybe Mr. Owen hasn't heard about the Sellwood Garden Club, our numerous LEED-certified buildings, or that we're the most bike-friendly city in the country? Or maybe he has, and he just doesn't care. It's clear only pages into Green Metropolis that if there's one thing Owen lacks patience for, it's those factions of the environmental movement that neglect what he identifies as the single most important element of truly sustainable living: density.

Owen's argument is simple. The vast majority of Manhattanites don't drive; they live in mixed-use neighborhoods that enable them to easily meet their basic needs, in apartment buildings that are more energy efficient than single-family homes. Consequently, residents of New York City generate only 7.1 metric tons of greenhouse gases per year—compared with a national average of 24.5.

This, Owen tells us, is where we should be looking for environmental guidance: Not to hydrogen cars, solar power, backyard compost bins, or recycling, but to a city that is widely regarded by environmentalists as an ecological nightmare.

Owen's basic premise (density = good; cars = bad) isn't particularly radical, but it's thoroughly supported with examples comparing rural, suburban, and urban communities and their relative energy consumption. Moreover, Owen is willing to go further than most in decrying the so-called "green ideology" that leads consumers to think nothing of driving 30 miles to seek out local produce, or building elaborately "sustainable" homes, instead of improving the homes they have.

Owen will appear in conversation with Ethan Seltzer, director of PSU's School of Urban Studies and Planning. It should make for an interesting discussion, particularly if Owen repeats terms like "putatively eco-friendly."