Posted on 08/20/2011 2:01:47 PM PDT by Ernest_at_the_Beach
Urban areas with at least one million inhabitants in 2006. 3% of the world's population lived in cities. Image via Wikipedia
From Yale University
Growth of cities endangers global environment
New Haven, Conn.—The explosive growth of cities worldwide over the next two decades poses significant risks to people and the global environment, according to a meta-analysis published today in PlosOne.
Researchers from Yale, Arizona State, Texas A&M and Stanford predict that by 2030 urban areas will expand by 590,000 square miles—nearly the size of Mongolia—to accommodate the needs of 1.47 billion more people living in urban areas.
“It is likely that these cities are going to be developed in places that are the most biologically diverse,” said Karen Seto, the study’s lead author and associate professor in the urban environment at the Yale School of Forestry & Environmental Studies. “They’re going to be growing and expanding into forests, biological hotspots, savannas, coastlines—sensitive and vulnerable places.”
Urban areas, they found, have been expanding more rapidly along coasts. “Of all the places for cities to grow, coasts are the most vulnerable. People and infrastructure are at risk to flooding, tsunamis, hurricanes and other environmental disasters,” said Seto.
The study provides the first estimate of how fast urban areas globally are growing and how fast they may grow in the future. “We know a lot about global patterns of urban population growth, but we know significantly less about how urban areas are changing,” she said. “Changes in land cover associated with urbanization drive many environmental changes, from habitat loss and agricultural land conversion to changes in local and regional climate.”
The researchers examined peer-reviewed studies that used satellite data to map urban growth and found that from 1970 to 2000 the world’s urban footprint had grown by at least 22,400 square miles—half the size of Ohio.
“This number is enormous, but, in actuality, urban land expansion has been far greater than what our analysis shows because we only looked at published studies that used satellite data,” said Seto. “We found that 48 of the most populated urban areas have been studied using satellite data, with findings in peer-reviewed journals. This means that we’re not tracking the physical expansion of more than half of the world’s largest cities.”
Half of urban land expansion in China is driven by a rising middle class, whereas the size of cities in India and Africa is driven primarily by population growth. “Rising incomes translate into rising demand for bigger homes and more land for urban development, which has big implications for biodiversity conservation, loss of carbon sinks and energy use.”
The paper, “A Meta-analysis of Global Urban Expansion,” can be viewed on the PlosOne website at http://dx.plos.org/10.1371/journal.pone.0023777.
Large mega-dense cities are so much more effective at spreading infectious diseases and plagues.
last week it was urban sprawl
Precisely. Out here in frontier country, they are trying to push us all into desified urban settlements through re-wilding. Sounds like the enviros aren’t talking to eachother and getting their game plan straight.
Precisely. Out here in frontier country, they are trying to push us all into densified urban settlements through re-wilding. Sounds like the enviros aren’t talking to eachother and getting their game plan straight.
yup... it's a case of two left hands where the left hand doesn't know what the Other left is doing
Often many of us just laugh at these clowns. But I know you know how damn serious it really is. What we need somehow is a eight year plus conservative president and majority rule in both Houses filled with ever growing numbers of serious minded politicians who will carefully and with great care see how this AGW movement in all it’s evil aspects must be put to an end. Big time.
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