This indicator is an estimate of the amount of space on the earth that an individual uses in order to survive using existing technology. This space includes the biologically productive land and water area that produces the resources consumed by that individual such as food, water, energy, clothing, and building materials. It also includes the amount of land and water required to assimilate the wastes generated by that person. In other words, the ecological footprint measures a person's demand on the bio-capacity of the Earth.
Overview of the Issue
As the graph shows, the amount of productive land used by North American doubled from 1900 to 1950 and doubled again between 1950 and 1995. In part this increase was due to increases in the economic quality of life that many North Americans enjoy. Indoor plumbing, central heating, telephones, automobiles and electric lights all increased the quality of life and the amount of productive land a person's resource use required. However, the ecological footprint is not as much a reflection of a person's standard of living as much as it is a reflection of a person's of style of living. 'In fact, this indicator is really a measure of a person's 'economic footprint'. The more a person consumes, the larger that person's ecological footprint, but consuming more does not necessarily mean a better quality of life.
The average US ecological footprint is 50% larger than the average person in most European countries in part because the US has more suburban sprawl, less public transportation, and uses more energy and water per person than most other developed countries. However, the 50% larger footprint does not necessarily mean a 50% better quality of life. For example:
- A person who walks or takes public transportation has a smaller footprint than someone who commutes alone fifty miles to and from work in a car (especially if that car only gets 15 miles to the gallon)
- A vegetarian has a smaller footprint than someone who eats a lot of meat
- A house or office park with a small amount of lawn has a smaller ecological footprint than a house or office park with acres of lawn treated weekly with chemicals and water.
This indicator was selected because gets at the heart of sustainability -- how much of the earth's resources does a person consume compared to the amount of resources available? In the short term, comparing ecological footprints of different people is a measure of intra-generational equity. In the longer term, the ecological footprint is a indicator of whether future generations will be able to meet their needs.
Carrying capacity of the community capital
Natural capital - This indicator focuses our attention on the need to consider the limits of the resources and ecosystems available for supporting the human population of the world. The average US ecological footprint is 50% larger than that of the average person in most European countries. The measure raises the question - are we 50% better off than people in the Netherlands? This indicator also reflects the third part of natural capital, beauty of nature.
Social capital - This indicator is not directly linked to social carrying capacity. A small ecological footprint may only reflect less consumption and waste due to poverty. However, a community that intentionally sets out to reduce the need for automobiles by reducing sprawl or improving public transportation will also improve social connectedness as result.
Built/financial capital - This is a reflection of wasted capital, in that all solid waste, including construction and demolition debris, contributes to an increased ecological footprint, whereas durable products contribute to built capital.
Linkages - This indicator links economy, environment and society in one package. Our mainstream societal habits are characterized by working long hours to pay for timesaving appliances and single use products that are then added to the waste stream.
Long term view - When we look at the footprint of the average North American, it is clear that we would exceed the carrying capacity of the earth if in the future, other populations adopted our average lifestyle. Even with the current world population count it is clear that our patterns of consumption are not sustainable, and projected future populations make it dramatically less so.
Understandable - This indicator converts relatively abstract concepts and large amounts of data relating to sustainability and carrying capacity into an easily visualized graphic representation.
Ways the Indicator Has Prompted Change
The ecological footprint is a useful indicator for educating people about the extent to which human consumption is overtaking the ability of the earth to support life. While there is a long way to go to before this becomes a widely accepted guideline for either personal or public decision making, it is nevertheless an excellent educational tool.
Data Sources and Additional Information
This indicator was developed by Mathis Wackernagel and William Rees and described in their book, Our Ecological Footprint: Reducing Human Impact on the Earth, 1996, available from New Society Publishers. This is a very easy-to-read book that explains how to calculate the footprint. Wackernagel now heads up an organization called the Global Footprint Network. Their web site, http://www.footprintnetwork.org/, has information on the footprint of different countries and the methodologies used. The footprint has been calculated for all countries in the world and the results compared to the available biological capacity in the Living Planet Report http://www.panda.org/news_facts/publications/living_planet_report/index.cfm.
To easily calculate your own ecological footprint, there are a number of websites to assist you, including:
The EarthDay Network's site's implementation is very nicely done: (http://earthday.net/footprint2/index.html )
An international one (metric measures) is the Best Foot Forward site's: (http://www.bestfootforward.com/carbonlife.htm)
Finally the World Wildlife Fund UK has a site that is nicely implemented: (http://footprint.wwf.org.uk/)
If you answer some basic questions about what you consume, these sites calculate your ecological footprint.
We are very interested in including comments from reviewers that add to the general discussion of measuring sustainability. As we receive appropriate comments, we will add them here. If you have comments about a particular indicator that you would like to include, please send us a message. Likewise, if your community or organization has an indicator that you think would be a good indicator to spotlight, please let us know.