One Planet, How Many People? A Review of Earth’s Carrying Capacity

http://igskmncnvs522.cr.usgs.gov/geas/archive/pdfs/GEAS_Jun_12_Carrying_Capacity.pdf

June 2012

The size of Earth is enormous from the perspective of a single individual. Standing at the edge of an ocean or the top of a mountain, looking across the vast expanse of Earth’s water, forests, grasslands, lakes or deserts, it is hard to conceive of limits to the planet’s natural resources. But we are not a single person; we are now seven billion people and we are adding one million more people roughly every 4.8 days (2). Before 1950 no one on Earth had lived through a doubling of the human population but now some people have experienced a tripling in their lifetime.

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it has been estimated that “if everyone lived the lifestyle of the average American we would need five planet Earths” to provide the needed land and ecosystem goods and services