Measuring Urban Sprawl
Published Wednesday, April 26, 2006 by CCAer | E-mail this post
The Neptis Foundation
, a Toronto-based organization that focuses on urban development, has utilized satellite and air photo data to create a 8.7 billion data cell image depciting land development in the United States. According to a paper entitled “Causes of Sprawl: A Portrait form Space” that will be appearing the Quarterly Journal of Economics
, Pittsburgh is more sprawling than Miami and recent development in Boston is more scattered than in Los Angeles.
“The authors merged high-altitude photos from 1976 with satellite images from 1992 (the most recent available) to create a grid of 8.7 billion 30-metre by 30-metre cells that tracks land use changes nationwide,” says a University of Toronto press release
. “The authors also investigated why some cities are more sprawling than others. They found that a city's climate, topography and access to groundwater account for 25 per cent of the nationwide variation. When the climate is temperate, people spread out to have more space to enjoy the weather. Hilly places see more scattered development as people avoid the costs of building on hillsides -- but mountains act as a barrier and lead to more compact development. Places with easy access to groundwater see more scattered development, since people can supply remote houses with water by drilling inexpensive wells rather than paying for water lines.”Read a version of the paper in pdf format
. An 11 x 17 version of the land development image of the United States
is also available as are other, more detailed images
of various American cities.