Cities sprawl

Cities sprawl Prominent among other land use changes is the continued growth of urban areas (see below). Builtup area per person continues to grow in the Markets First scenario, tending towards the sprawling settlement patterns of North America. Despite relatively compact settlement patterns in Policy First compared to Markets First, higher income growth is accompanied by a more rapid expansion in built-up land. As a result, the built-up area in Policy First is only slightly below Markets First. Unplanned expansion and rapid population growth lead to substantial growth in built-up area in Security First. In Sustainability First, as in Policy First, a tendency towards compact settlement patterns is offset by more rapid economic expansion. However, the offset is only partial and total built-up area grows least in this scenario.

Extent of built-up areas: Latin America and the Caribbean (% of total land area)
Source: PoleStar (see technical annex)
Energy-related nitrogen oxide emissions: Latin America and the Caribbean (million tonnes nitrogen)
Source: IMAGE 2.2 (see technical annex)

Key to charts

Expansion of urban conditions raises problems of water quality, waste management, air pollution and general sprawl throughout much of Latin America. Economic driving forces continue to attract people to the cities, especially in Markets First. Without improved planning and organization, the environmental pressures on urban areas, especially in mega-cities, continue to grow as the rates of population growth outpace that of infrastructure development. This effect is stepped up in a Security First world, where the affluent increasingly withdraw into their enclaves, denying the poor access to safe drinking water, sanitation and health services. The quality and quantity of water and the disposal of solid waste are major worries in the small island countries and territories of the Caribbean. Unchecked air pollution has serious and costly health impacts, especially for urban populations (see chart above).

In a world of Policy First, measures to curb urban migration and to improve public transportation systems and the collection, disposal and recycling of domestic and industrial wastes, diminish - but do not eliminate - the vulnerability of cities and their inhabitants to human-induced and natural disasters. More success is achieved in a world of Sustainability First. Air pollution declines due to effective regulation and targeted technological progress. The dissemination of sound knowledge and scientific advice, and the transfer of appropriate technology, further improve waste management. Waste generation declines in relative terms and its quality and composition allows for higher rates of reuse, recycling and use in energy production. Finally, more equitable distribution of income and wealth between urban and rural areas has a moderating effect on rural-to-urban migration.