Way back in June (seems so long ago, doesn’t it?) I posed the question of what constitutes a city. People frequently cite the statistic that half the world’s population will soon live in cities, but those 3.4 billion people will not be living in anything close to downtown Manhattan. The definition of “urban” under which the majority of the planet’s people live in urban areas is more inclusive than what people usually think of as a city — the mega-cities like New York or London.

Considering this, I picture the view looking west from Manhattan. The first time I saw it, it hardly looked like a major city at all, just abnormally dense suburbia. While it does have the efficient mass transportation net characteristic of many cities, Brooklyn is lacking in density.As Clark pointed out, density is a huge energy saver. The decreased environmental impact of living in a city is largely due to the sheer density of people and their proximity to their needs and wants, although it’s not for everyone, as bhurley points out.

Nathan Newman over at tpmcafe posts about the planned developments in Brooklyn’s Atlantic Yards (as well as Manhattan’s West Side). The debate is being framed as people who are nostalgic for Brooklyn low-rise residence and want to keep high-density building out versus those who see the site as a prime residential location, given its proximity to mass transit. Newman shuns progressives who are opposed to the new development, as they “condemn others to homelessness and the rest to increasingly long commutes.”

The Brooklyn development has promised a number of units designated “affordable housing,” increasing the allure. Smart Growth Online, in timely fashion, recently published a report detailing ways different states are using housing-credit plans to make housing that’s not only affordable but environmentally friendly — if high-density housing a mere walk away from mass transit to New York City isn’t enough.

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