They're alive!! Megacities breathe, consume energy, excrete wastes and poll

WASHINGTON

Charles Kolb, Ph.D., reports that the concept of urban metabolism has existed for decades. It views large cities as living entities that consume energy, food, water, and other raw materials, and release wastes. The releases include carbon dioxide, the main greenhouse gas; air pollutants, sewage and other water pollutants; and even excess heat that collects in vast expanses of concrete pavement and stone buildings. Humans directly produce a significant share of this waste, but emissions from industrial, power generation and transportation systems respire the largest quantities of greenhouse gases and other air pollutants. Other urban metabolizers include sewage systems, landfills, domestic pets and pests like rats, which in some cities outnumber people.

EurekAlert