Jan 08 2011
This is a cross post by KerrisG in the other class (your class has less folks to assign scribe duties to).
Our text defines urbanization as the shift from people living in rural areas to people living in urban areas and is probably the greatest change our society has undergone since the transition from a hunter-gatherer lifestyle to a settled agricultural lifestyle. What exactly is an urban area? An urban area is place with a population of 2,500 or more people. This said, around 50% of the earth’s population lives in urban areas, those urban areas only occupy about 3% of Earth’s land surface area.
Is this statistic good news or bad news for the future of our planet? It all depends on who you ask. An environmentalist would say that dense, crowded cities are very much a good thing because more forests and farmlands are being preserved. However, some environmentalists would deem this a bad situation because these urban areas, especially the highly populated cities, require many inputs and therefore produce just as much waste. This waste is taken out of the urban areas and will most likely be buried in the farmlands.
An urban area, and especially a city, is a system. All systems receive inputs, process these inputs, and produce outputs. CITIES AND URBAN AREAS ARE NOT SELF-SUSTAINING; they rely on importing almost all their necessities to function. Here are the inputs and outputs of a city system:
Pollution (water, air, light, noise)
Energy (gas, electricity)
The production of money and jobs in urban areas provokes wealth, education, technology, and health. The massive amount of heat produced by cities gave rise to cities being nicknamed “heat islands.” This is because the dark asphalt of the paved roads absorbs the heat from the sunlight and then slowly releases it back into the city air.
A Quick Introduction to Urban Sprawl:
Sprawl is the spread of low-density urban or suburban development outward from an urban center. Urban sprawl is more likely to occur in the “developing” countries of the world because the Average Growth Rate of these countries is much higher than in “developed” countries, so, the populations of urban areas in “developing” countries are growing much more rapidly, creating a need to increase the size of the urban area. Regarding the statistic I began my post with, research shows that by 2030, 60% of the world population will live in urban areas.
To see examples of urban sprawl in different countries around the world from the 1970s to 2000, click the UN Urbanization Preso Slides in the Box. These are the pictures we looked at today in class.