Close examination of thousands of satellite photos has revealed that cities represent 0.63% of the national land area in Brazil, or 54,077 square kilometers (km2), which is slightly larger than the total area of the state of Rio Grande do Norte. The most urbanized region is São Paulo, followed by Rio de Janeiro and Brasília (see table). According to the three-year study coordinated by geographer André Rodrigo Farias, from the Territorial Management Division of the Brazilian Agricultural Research Corporation (EMBRAPA Gestão Territorial) in Campinas, São Paulo, about 175 million people in Brazil, or 84% of the population, live in cities. The total is lower than previously found by the Brazilian Institute of Geography and Statistics (IBGE) in the 2010 demographic census (104,515 km2, equivalent to 1.2% of the national land area). The difference is caused by the methodologies used. The IBGE considers urban areas according to the perimeter defined by municipal law. In the Embrapa study, the researchers defined cities as the areas that actually appeared as built-up urban zones in high-resolution satellite images. They were thus able to eliminate areas within the municipal urban perimeter that have not been built on. Mapping the territory of cities is important to public policy decisions and to identifying the boundaries of agricultural expansion.
