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DATE: June 25, 2002
CONTACT: Craig Cheslog (510-444-3041)

Paper Published This Week in Proceedings of the National Academy of Sciences

Please follow this link to read the paper (pdf format).

OAKLAND, Calif.—Humanity's use of natural resources, or Ecological Footprint, has exceeded the regenerative capacity of the Earth since the 1980s. The finding is outlined in a paper to be published this week in the journal Proceedings of the National Academy of Sciences (PNAS).

Redefining Progress Sustainability Program Director Mathis Wackernagel is the lead author of the paper, "Tracking the ecological overshoot of the human economy." He and his colleagues reached this conclusion by comparing humanity's demand on the environment to the earth's supply of bioproductive areas over the past 40 years.

"Sustainability requires living within the regenerative capacity of the biosphere," write Wackernagel and his colleagues. "In an attempt to measure the extent to which humanity satisfies this requirement, we use existing data to translate human demand on the environment into the area required for the production of food and other goods, together with the absorption of wastes."

The researchers assessed the total area globally available for growing crops, grazing animals, harvesting timber, accommodating infrastructure, marine fishing, and absorbing carbon dioxide produced by burning fossil fuels. They then calculated how much area would be required to sustainably meet human demand for these various activities.

According to this analysis, human demand (or Ecological Footprint) in 1961 was about 70 percent of the Earth's regenerative capacity. By the 1980s demand had risen to match total global supply, and by 1999 demand exceeded supply by at least twenty percent. It takes the biosphere, therefore, at least a year and three months to renew what humanity uses in a single year.

Other authors of the paper include: Niels B. Schulz of the Institute of Interdisciplinary Studies of Austrian Universities; Diana Deumling and Chad Monfreda of Redefining Progress; Alejandro Callejas Linares of the Centro de Estudios para la Sustentablilidad; Martin Jenkins and Valerie Kapos of the World Conservation Monitoring Centre; Jonathan Loh of WWF International; Norman Myers of Green College, Oxford University; Richard Norgaard of the Energy and Resources Group, University of California, Berkeley; and Jørgen Randers of the Norwegian School of Management.

Redefining Progress is a nonpartisan public policy organization that creates policies and tools to encourage accurate market prices, preserve our common assets, and foster social and economic sustainability.