Making Room for a Planet of Cities (Policy Focus Reports)

In a rapidly urbanizing world -- over half the world's population lives in urban areas, including many millions in informal settlement. The large cities of the developing world in particular are expanding. Yet there is little in the way of planning and preparation for this explosive growth in urban population. Making Room for a Planet of Cities is a comprehensive and original analysis of the quantitative dimensions of past, present, and future global urban land cover, culminating in a proposed new paradigm for preparing for explosive growth in cities the world over. Carefully selected metrics measured in four new data sets with ArcGIS software provide a comprehensive and consistent global and historical perspective on urban expansion. These data sets are: 1. The built-up areas of a global sample of 120 cities with 100,000 people or more, 1990 and 2000, based on satellite images; 2. Historic population density data in digital images for 20 U. S. cities, 1910-2000, based on census tracts; 3. Built-up areas of a representative global sample of 30 cities, 1800-2000, from the set of 120 cities based on historic maps; and 4. Urban land cover areas of the universe of 3,646 cities that had