"Growth of cities endagers global environment"

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.

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.

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.

http://www.sciencedaily.com/releases/2011/08/110819155428.htm