Causes of Sprawl: A Portrait from Space

Posted by: Chris Steins
Thanks to: Peter Gordon

10 October 2006 - 1:00pm

Researchers calculate We calculate a 'sprawl index' for all metropolitan areas and then examine the reasons why sprawl differs across space.

From the research abstract by Marcy Burchfield, Henry G. Overman, Diego Puga and Matthew A. Turner: "We study the extent to which U.S. urban development is sprawling and what determines the differenecs in sprawl across space. Using remote-sensing data to track the evolution of land use on a grid of 8.7 billion 30x30 meter cells, we measure sprawl as the amount of undeveloped land surrounding an average urban dwelling. The extent of sprawl remained roughly unchanged between 1976 and 1992, although it varied dramatically across metropolitan areas. Ground water availability, temperate climate, rugged terrain, decentralized employment, early public transport infrastructure, uncertainty about metropolitan growth and unincorporated land in the urban fringe all increase sprawl."

From the paper:
"...1.9 percent of the land area of the United States was developed by 1992. Two thirds of this developed land was already in urban use around 1976, while the remaining one third was developed subsequently. Our main findings are concerned with whether development is sprawling or compact. We measure sprawl as the amount of undeveloped land surrounding an average urban dwelling. By this measure, commercial development has become somewhat more sprawling during the study period but the extent of residential sprawl has remained roughly unchanged between 1976 and 1992. In contrast to this stability over time, the extent of sprawl does vary dramatically across metropolitan areas."

[Editor's note: Although the first link below is to The Quarterly Journal of Economics, which charges a fee to access the article, the second link is to the resarcher's own website, which features a PDF version of the article.]

Full Story: Causes of Sprawl: A Portrait from Space

Source: The Quarterly Journal of Economics, October 6, 2006

measuring "development"

Submitted by William Travis on Thu, 10/12/2006 - 11:51.

Maybe it is just because I'm a geographer, not an economist, but I think this article is flawed in terms of its spatial thinking and definitions of development and sprawl. For starters, development is literally defined as any 30X30 m patch holding a building or road (or other obvious structure). I'm not surprised that only 1.9% of the U.S. is developed or urbanized by this definition because, as the authors note, the non-built spaces among buildings would not be considered developed (including some of the big lawns I just saw on a drive around Massachusetts this weekend). This is news! The pro-sprawl theorists would love the headline: "Study finds only 1.9% of US is developed!" I wonder where all the open space, habitat and species went with just this frontier density of development? It also seems to me that the authors are measuring exurbia, not what most observers would think of a suburban sprawl. The index understates sprawl, I think. Anyone driving around an area in which, say, every 10th 30X30 m pixel had a building on it would certainly think they are in a developed landscape. Finally, the fact that a city footprint can grow substantially but keep the same sprawl index speaks to a very specialized measure that, however useful in terms of tracking changing (or unchanging) form of development, again does not capture a lot of what both lay and professional observers would term as sprawl.

Bill Travis
Dept. of Geography
University of Colorado

Link broken

Submitted by Dano on Tue, 10/10/2006 - 13:05.

The redirect isn't working.

Best,

Link Seems Ok

Submitted by Chris Steins on Wed, 10/11/2006 - 15:45.

Hi Dano,

Thanks for your post.

I was able to click on both links with no problems. The first link is to the journal article (only available for a fee). The second link is to an approximately 2MB PDF document. Since the document is so large, could it be that the link seemed not to be working because it takes a while for the 2MB PDF document to download and open?

Thanks,

Chris Steins, Editor
Planetizen - www.planetizen.com