Thursday, November 16, 2006

Ecological Footprint : Stepping Toward Sustainability

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Ecological footprint analysis is a tool for measuring the impact of human activity on the earth. It was developed in the mid-1990s, and it has been taken up around the world by researchers who are interested in the issue of sustainability. Ecological footprint analysis tells us how much biologically productive land is required to support an individual or population based on the resources they consume and the waste they generate. This allows us to explore a key aspect of sustainability: how well are we living within the means of nature?

For all of the time humans lived on earth up until the 1980s, our collective footprint remained within the area that the earth could afford us. But since then, we have overstepped our bounds by an increasing amount every year.

The most recent annual calculations published by the World Wildlife Fund (See WWF's Living Planet Report) indicate that the current global average ecological footprint stands at about 5.4 acres per person. That may not sound like a lot, but in fact it’s nearly 25% more than nature can provide on a continuous basis. We’re able get that extra 25% for now by depleting stocks of natural resources that have accrued over millions of years.

Ecological footprint analysis also provides information about the relative impacts created by people living in different countries. The United States, which is second only to the United Arab Emirates in this regard, has a per-capita ecological footprint of 24 acres per person. That’s about 4 times the global average, and about 5 times what the earth can support on a continuous basis. If all the people alive on earth today had access to an American standard of living we would need 5 planets to support us.

Now, you may hear that and think, whoa, too much—somebody else is going to have to figure that one out.

But the cool thing about ecological footprint analysis is the way it can be used by individuals and communities who are interested in moving toward a more sustainable lifestyle. It helps you see which of your choices have the most significant impacts on the earth, and enables you to track your progress as you make adjustments in the way you do things.

You can measure your own ecological footprint using the web-based calculator at

When I took the quiz I came out with a footprint of 20 acres. That’s way over the 4.5 acres available per person as a global average. But it’s not so far over the available biologically productive land in the United States, which is about 12 acres per capita. So, rather than despairing because no change I make can reduce my footprint to the average that the earth as a whole will support, I’m aiming to reduce my footprint to what the land of the U.S. can support. In other words, I want to go from 20-acre footprint to a 12.

That’s still a substantial task, but one that’s do-able over time, and really worth engaging. By reducing our own ecological footprints, we bring ourselves into a more equitable relationship to the other people with whom we share the earth, now, and in the future.

Thanks to Rumi Shammin, a soon-to-be Ph.D. in the Department of Natural Resources and Environmental Sciences at the U of I for help with today’s show.