Urbanization

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Percentage of population which is urbanized, by country, as of 2006.[1]
Percentage of World Population: Urban vs. Rural.[2]

Urbanization (or urbanisation) is a term from geography. The base of the word is the Latin urbs, which means city. The term urbanisation means that lifestyle that is common in a city becomes prevalent. This can happen in two different ways:

  1. Through the growth of cities; called physical urbanization
  2. Through the change of behaviour of people living in rural areas; called functional urbanization

Physical urbanization has been observed for centuries. In developing countries this is the main form of urbanization. In developed countries, functional urbanization is the main form of urbanization. With functional urbanization, people living in the city center move to the countryside, next to the city; this is known as suburbanization.

Environmental effects[change | change source]

Environmental scientists are studying the urban heat island. The urban heat island is made when industrial and urban areas are developed and heat becomes plentiful. In country areas, a large part of the incoming solar energy is used to evaporate water from vegetation and soil. But cities have less vegetation and soil. In cities, most of the sun’s energy is absorbed by urban building and asphalt paving. During warm daylight hours, there is less evaporative cooling in cities than in country areas. So, surface temperatures rise higher in cities than in country areas. Also, vehicles, factories, and industrial and domestic heating and cooling units give off more heat in cities. This problem is growing.[3] This effect causes the city to become 2 to 10o F (1 to 6o C) warmer than surrounding rural areas.[4] Environmental impacts also include reducing soil moisture and intensification of carbon dioxide emissions.[5]

Stewart Brand's book Whole Earth Discipline argues that urbanization helps the environment overall. First, the birth rate of new urban dwellers falls immediately to replacement rate, and keeps falling. This can prevent overpopulation in the future. Secondly, it puts a stop to destructive subsistence farming methods, like slash and burn agriculture. Finally, it reduces land use by humans, leaving more for nature.[6]

References[change | change source]

  1. "Statistical Tables". http://www.unicef.org/sowc08/docs/sowc08_table_StatisticalTables.pdf. Retrieved 15 October 2010.
  2. "United Nations, Department of Economic and Social Affairs". http://esa.un.org/unup/.
  3. Park, H.-S. (1987). Variations in the urban heat island intensity, affected by geographical environments. Environmental Research Center papers, no. 11. Ibaraki, Japan: Environmental Research Center, The University of Tsukuba.
  4. "Heat Island Effect". U.S. Environmental Protection Agency. http://www.epa.gov/heatisland. Retrieved 2011-10-21.
  5. "Heating Up: Study Shows Rapid Urbanization in China Warming the Regional Climate Faster than Other Urban Areas". http://gtresearchnews.gatech.edu/newsrelease/china-climate.htm.
  6. Brand, Stewart. "Whole Earth Discipline - annotated extract". http://web.me.com/stewartbrand/DISCIPLINE_footnotes/2_-_City_Planet.html. Retrieved 2009-11-29.