A Planet of Cities: Urban Land Cover Estimates and Projections for All Countries, 2000-2050

We created a new data set comprising the universe of all 3,649 named metropolitan
agglomerations and cities that had populations in excess of 100,000 in the year 2000,
their populations in that year, and their built-up area identified in the MOD500 map,
currently the best satellite-based global map of urban land cover. Using this data set, we
estimated urban land cover in smaller cities and towns in all countries and calculated total
urban land cover in every country in the year 2000. We then employed multiple
regression models that could explain more than 90 percent of the variations in urban land
cover among countries. Then, using U.N. urban population projections in combination
with three realistic density change scenarios based on our previous global and historical
study of densities, we projected urban land cover in every country and world region from
2000 to 2050.