Ecological footprint

The ecological footprint: an indicator of thresholds that must not be exceeded

First developed by researcher Mathis Wackernagel in the 1990s, the concept of ecological footprint (EF) was taken up by the United Nations Environment Program, the International Union for Conservation of Nature (IUCN), and the WWF after 1999. This indicator provides an assessment of the impact of human activity on nature. For any given country, group, or individual, the ecological footprint measures the productive area required to supply the demand for resources, as well as the area necessary to absorb the waste generated.
In making this calculation, the ecological footprint considers resource consumption and waste production arising from four main activities: food, transportation, housing, and consumer goods and services. This figure is plotted against the surface area required for production and waste absorption, namely:
- arable land (under cultivation);
- grazing land (livestock);
- forests (forestry);
- waters (fishing waters);
- land used for building;
- land used for fossil fuel energy production or C02 capture to offset the greenhouse effect.

the advantage of this indicator is its premise that there are limits which must not be exceeded. It pulls away from reasoning in strictly monetary terms, postulating instead that the Earth must both supply society’s needs and absorb its pollution.

The ecological footprint goes hand in hand with the idea of “biocapacity”, which is the useable total of biologically productive areas. Stripping out Earth’s vast, unproductive areas (deserts, mountaintops, the high seas), the total useful surface comes to 11.4 billion ha, or a quarter of the planet. When this figure is divided by the world population (6.3 billion), the average annual surface area per capita is 1.8 ha. In other words, from a sustainable viewpoint, every inhabitant of Earth should have 1.8 ha in which to supply their own needs and absorb their waste; above that, soils are degraded, and below that, the planet has the ability to regenerate itself. In view of changes in demographics, increased consumption, and resulting environmental consequences, the global ecological footprint has exceeded the planet’s biocapacity since late 1970s. Today’s demands on Earth are equivalent to those of 1.25 planets. Society therefore uses considerably greater resources than Nature can supply.

If the entire world population consumed as much as Europe and Japan, that figure would come to 2.5 planets. If world consumption equalled that of the United States, 5 planets would be required, while Singapore would require 3 planets. South Korea’s ecological footprint is similar to Japan’s. However, a very light ecological footprint is not necessarily a good sign. Those countries with the smallest footprints often face crippling difficulties, such as in Sub-Saharan Africa or the Caribbean. Conversely, several countries with balanced development, such as Costa Rica or Thailand, have a sustainable EF.

The ecological footprint model is criticised by some who object that CO2 emissions cannot be correlated to forest areas. However, opposing voices are mainly heard from those fearing the resulting questioning of economic growth. Whatever the case, besides its statistical limitations, the ecological footprint model presents the advantage of highlighting the environmental thresholds that human society is bypassing without the technical means to guarantee its own future, let alone that of future generations. Without advocating a return to the use of candles, the ecological footprint model encourages us to consider environmental consequences and risks to a greater extent than GDP per capita or the HDI.