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Ecological Footprint
by Adam Szuch
From The Ground Up, March 2002

Environmentalists believe that we can lessen our environmental impact by reducing dependence on fossil fuels, cutting household waste, and consuming fewer resources. But just how much of an effect do these actions have? Can we put a number on our environmental impacts? Is it possible to see whether our living choices are in proportion with global resource consumption and regeneration as well as waste generation and disposal?

The Ecological Footprint model attempts to answer these and other challenging questions as we search for a more sustainable future. The concept was first introduced by Mathis Wackernagel and William Reese in 1994. As argued by Wackernagel and Reese, the Ecological Footprint model sets itself apart from earlier studies in that it aggregates a number of impact measurements and expresses results in easily comparable units, while building on specific definitions for sustainable development.

According to Redefining Progress, a non-profit public policy and research organization based in San Francisco, the Ecological Footprint is based on two assumptions: 1) we can keep track of most of the resources that we consume as well as many of the wastes we generate; and 2) we can measure the resource consumption and disposal flows as they compare to corresponding biologically productive areas. Based on these assumptions, Redefining Progress defines the Ecological Footprint of an individual up to an entire nation as, "The area of biologically productive land and water required to produce the resources consumed and to assimilate the wastes generated by that population using prevailing technology." For most calculations, the amount of land required is measured in acres. Ecological Footprint concept can be accounted for using different methodologies, however most calculations take into account fossil fuel use and production, carbon dioxide production and assimilation, waste assimilation, built up land, land occupied for forestry or agriculture, fisheries, distribution of resources, area efficiency and population growth. Not factored in to Ecological Footprint calculations are damages including ozone depletion, toxic waste, and greenhouse gasses other than Carbon Dioxide.

So, what have been the results of recent Ecological Footprint calculations? Of course, the use of slightly different calculation methods bring about slightly different results. However, most calculation methods arrive at similar figures. The Redefining Progress study titled, Ecological Footprint of Nations, relays some alarming figures. Based on 1997 United Nations statistics, EFON compares the Ecological Footprints of 52 nations around the globe. The study concluded that the average American requires approximately 30.8 acres of productive land to provide for his or her consumption. Compare this to the average German using only 14.9 acres and the world average of only 7.1 acres, and America seems to be a bit out of place.

To put these numbers into sustainability terms, these numbers must be compared to estimated productive land totals. According to the Redefining Progress study, the U.S. has more abundant natural resources from which to draw than the world average. The U.S. has a capacity of 13.6 acres per person compared to the world average of only 5.3 acres. Of course, the average use of 30.8 acres shows that the U.S. has a clear "ecological deficit." The study points to two factors that lead to this deficit: Imported ecological capacity and depletion of domestic resources. To put these figures into perspective, Wackernagel's team estimates that for the entire world to live at the current consumption rate of the US, over 4 planets would be needed. Redefining Progress also suggests that the world as a whole is using up resources faster than they can be renewed and generating more waste than can be absorbed.

The results of such studies stand as reference to planners and policy makers searching for sustainable practices and systems for years to come. On the individual level, Ecological Footprinting offers an effective way to measure our environmental impact. Just as is the case with policy makers and planners, we as American citizens have our work cut out for us. Even with comparatively "green" life choices, the results of Ecological Footprint calculators can be humbling. To calculate your Footprint on line, visit the Real Progress website, www.rprogress.org.. For practical suggestions on how you can reduce you Ecological Footprint visit the Recycle Ann Arbor En-House at 2420 S. Industrial Hwy. The demonstration model home features a room-sized display dedicated to the concept of Ecological Footprint.