Ecological Footprint

From Wikipedia, the free encyclopedia and Encyclopedia of Science, Technology, and Ethics

 

 

Ecological footprint (EF) analysis measures the human demand on nature and compares human consumption of natural resources with the earth's ecological capacity to regenerate them. It is an estimate of the amount of land area a human population, given prevailing technology, would need if the current resource consumption and pollution by the population is matched by the sustainable (renewable) resource production and waste assimilation by such a land area. It is controversial with several criticisms regarding the methodology.

 

Ecological Footprint Analysis

The term was first coined in 1992 by William Rees, a Canadian ecologist and professor at the University of British Columbia.[1] In 1995, Rees and coauthor Mathis Wackernagel published Our Ecological Footprint: Reducing Human Impact on the Earth.

Ecological footprint analysis approximates the human impact upon the environment by calculating the draw upon ecologically productive land and marine area required to sustain a population, manufacture a product, or undertake various activities. This is achieved through a system of accounting similar to life cycle analysis wherein the consumption of energy, biomass (food, fiber), building material, water and other resources are converted into a normalized measure of land area dubbed 'global hectares' (gha).

Per capita EF is a means of determining relative consumption and can be a useful tool to educate people about carrying capacity and over-consumption, with the aim of altering personal behavior. Ecological footprints may be used to argue that many contemporary lifestyles are not sustainable. The average "earthshare" available to each human citizen is approximately 1.9 gha per capita. The US footprint per capita is 9.5, and that of Switzerland is 4 gha. The average ecological footprint for Chinese citizen calculated in 2006 is 2.0 (meaning that it takes two global acres of resources to sustain each individual). The average footprint in Beijing is 6.2, indicating that urban residents consume more energy than rural dwellers. The WWF claims that the human footprint has exceeded the biocapacity (the available supply of natural resources) of the planet by 25%.[3]

 

Criticisms

The statistical methods used have been criticized on various grounds. The calculations also require numerous assumptions, many of which may be questioned.[6]

In most developed nations, fossil fuels use are responsible more than 50% of the EF. This is based on estimating the land area and plants, such as new forests, needed to sequester (recapture) the CO2 released from burning fossil fuels. Critics argue that this is an very unlikely and uneconomic way to stop global warming. There are many other methods for mitigation of global warming which do not require such large land use.[7] There have been efforts to address this old criticism, such as calculating the amount of land necessary to provide sufficient biomass to meet the energy demand. (This is different from sequestering fossil carbon as it brings human energy systems into the continuous carbon cycle.) However the options are limited due to the fact that, as formulated, the EF can only account for consumption of renewable resources, or perfect substitutes thereof as if the renewable resource had been used.

Calculating the ecological footprint for densely populated areas, such as a city or small country with a comparatively large population e.g. New York and Singapore respectively may lead to the perception of these populations as "parasitic". This is due to the fact that these communities have little intrinsic biocapacity, and instead must rely upon large hinterlands. Critics argue that this is a dubious characterization since mechanized rural farmers in developed nations may easily consume more resources than urban inhabitants, due to transportation requirements and the unavailability of economies of scale. Furthermore, such moral conclusions seem to be an argument for autarky. Some even take this train of thought a step further, claiming that EF denies the benefits of trade. Therefore, the critics argue that that EF can only be applied globally.[8]

The method seems to reward the replacement of original ecosystems with high-productivity agricultural monocultures by assigning a higher biocapacity to such regions. For example, replacing ancient woodlands or tropical forests with monoculture forests or plantations may improve the ecological footprint. Similarly, if organic farming yields were lower than those of conventional methods, this could result in the former being "penalized" with a larger ecological footprint.[9] Of course, this insight, while valid, stems from the idea of using the footprint as one's only metric. If the use of ecological footprints are complemented with other indicators, such as one for biodiversity, the problem is moot. Indeed, the WWF's Living Planet Report complements the biennial EF calculations with the Living Planet Index of biodiversity.[10]

 

In the early 1990s, Dr. William Rees and a graduate student, Mathis Wackernagel, developed and quantified the first "ecological footprint" for the city of Vancouver, Canada. Fundamental to this research was answering the question, "how large an area of productive land is needed to sustain a defined population indefinitely, wherever on earth that land is located?" Ecological footprints build on earlier studies, all designed to quantify the natural resources used by humans and compare that to those that are available. However, footprints are distinguished, according to leading practitioners, by the many categories of human activity included in the analysis, and by the measure's ability to compare current demand with current ecological limits (biocapacity).

 

 

Ecological Footprint Results 1999

SOURCE: World Wildlife Fund
Ecological footprint and biocapacity figures for representative countries around the world. Ecological deficit refers to the extent that a country's footprint exceeds its biocapacity.

 

Total Footprint

Biocapacity

Ecological Deficit

Total Footprint

Biocapacity

Ecological Deficit

 

World

2.3

1.9

−0.4

5.6

4.7

−0.9

Argentina

3.0

6.7

3.6

7

16

9

Australia

7.6

14.6

7.0

19

36

17

Austria

4.7

2.8

−2.0

12

7

−5

Bangladesh

0.5

0.3

−0.2

1.3

0.7

−0.6

Belgium & Luxembourg

6.7

1.1

−5.6

17

3

−14

Brazil

2.4

6.0

3.6

6

15

9

Canada

8.8

14.2

5.4

22

35

13

Chile

3.1

4.2

1.1

8

10

3

China

1.5

1.0

−0.5

4

3

−1

Colombia

1.3

2.5

1.2

3

6

3

Costa Rica

2.0

2.3

0.4

5

6

1

Czech Republic

4.8

2.3

−2.5

12

6

−6

Denmark

6.6

3.2

−3.3

16

8

−8

Egypt

1.5

0.8

−0.7

4

2

−2

Ethiopia

0.8

0.5

−0.3

1.9

1.1

−0.8

Finland

8.4

8.6

0.2

21

21

0

France

5.3

2.9

−2.4

13

7

−6

Germany

4.7

1.7

−3.0

12

4

−7

Greece

5.1

2.3

−2.8

13

6

−7

Hungary

3.1

1.7

−1.3

8

4

−3

India

0.8

0.7

−0.1

1.9

1.7

−0.2

Indonesia

1.1

1.8

0.7

3

5

2

Ireland

5.3

6.1

0.8

13

15

2

Israel

4.4

0.6

−3.9

11

1

−10

Italy

3.8

1.2

−2.7

9

3

−7

Japan

4.8

0.7

−4.1

12

2

−10

Jordan

1.5

0.2

−1.4

4

0

−3

Korea (Republic)

3.3

0.7

−2.6

8

2

−6

Malaysia

3.2

3.4

0

8

8

1

Mexico

2.5

1.7

−0.8

6

4

−2

Netherlands

4.8

0.8

−4.0

12

2

−10

New Zealand

8.7

23.0

14

21

57

35

Nigeria

1.3

0.9

−0.4

3.3

2.2

−1.1

Norway

7.9

5.9

−2.0

20

15

−5

Pakistan

0.6

0.4

−0.2

2

1

−1

Peru

1.2

5.3

4.2

3

13

10

Philippines

1.2

0.6

−0.6

2.9

1.4

−1.5

Poland

3.7

1.6

−2.1

9

4

−5

Portugal

4.5

1.6

−2.9

11

4

−7

Russia

4.5

4.8

0.4

11

12

1

South Africa

4.0

2.4

−1.6

10

6

−4

Spain

4.7

1.8

−2.9

12

4

−7

Sweden

6.7

7.3

0.6

17

18

2

Switzerland

4.1

1.8

−2.3

10

4

−6

Thailand

1.5

1.4

−0.2

4

3

0

Turkey

2.0

1.2

−0.7

5

3

−2

United Kingdom

5.3

1.6

−3.7

13

4

−9

United States

9.7

5.3

−4.4

24

13

−11


The ecological footprint is an environmental accounting tool that measures human impact on nature, based on the ability of nature to renewably produce the resources that humans use and absorb the ensuing waste. Footprinting provides a way to aggregate into a single composite measure many of the ecological impacts associated with built-up land (i.e., roads and buildings), food, energy, solid waste, and other forms of waste or consumption. The result represents the impact or footprint. Using an area-based measure, such as hectares or acres, the size of a footprint can be compared to the renewable services the Earth's biocapacity can produce in a given year. The footprint methodology can be used to evaluate a population's progress toward ecological sustainability.

The footprint has been criticized on a variety of fronts, primarily related to the complex methodology that underlies the measure, as well as the applications for which it is appropriate. Along with other aggregate indicators, the footprint has been criticized for obscuring the components and assumptions that comprise the measure. While the methodology behind the measure is readily available, it is complicated and therefore not approachable without some technical background. Other critics argue that the premise of living within resource limitations can be overcome with technological innovation. It is true that in many ways the footprint is a worst-case scenario because it describes the situation if there are no technological improvements; but the converse, counting on improvements, could be risky in the long run as well.

When a country or community uses more renewable resources than are available, it has exceeded ecological limits. It will not be sustainable over an indefinite period of time. Such a situation can occur over a relatively short time-span because natural capital can be depleted to fill the renewable resource gap. Imports can also meet society's needs, but may simply shift depletion of natural capital around the globe. Over time, global stocks may be depleted to the point where they cannot regenerate or require significant human intervention to do so.