1 Applying Geospatial Technologies in Urban Environments

Cities have been around since the 3rd millennium B.C. and as long as they have existed, people have been drawn to them for what they offer. As recently as 1800, however, only 2 per cent of the world’s population lived in urban areas. Today, with 6 billion people on earth, slightly less than one-half live in cities and towns; by 2007 one half of them will. In the century ahead, urban centres are expected to expand to sizes never before seen. United Nations, Instanbul + 5, 2001, p. 1 1.1 About this book As the epigraph suggest, cities are to become one of the chief policy concerns of the 21st century. Moreover, cities are unique policy realms in that urbanization is an issue and process that resides at the nexus of human and physical systems and unites the research and policy interests of natural and social scientists alike. This is true as urbanization as a process unites often-disparate social and physical sys-tems to create entirely new policy challenges such as environmental degradation, the development and maintenance of physical and social infrastructures, the chal