Conceived in 1990 by Mathis Wackernagel and William Rees at the University of British Columbia, the Ecological Footprint is now in wide use by scientists, businesses, governments, individuals, and institutions to monitor ecological resource use and advance sustainable development.
The Ecological Footprint - the metric that allows us to calculate human pressure on the planet. It compares human demand with planet Earth's ecological capacity to regenerate. If everyone lived the lifestyle of the average American we would need 5 planets.
The Ecological Footprint has emerged as the world’s premier measure of humanity’s demand on nature. It measures how much land and water area a human population requires to produce the resource it consumes and to absorb its wastes, using prevailing technology.
The Ecological Footprint, in its most basic form, is calculated by the following equation:
EF = YANNUAL/DANNUAL
where D is the annual demand of a product and
Y - the annual yield of the same product.
Yield is expressed in global hectares.
Ecological footprint of consumption
The Ecological Footprint of consumption for a given country measures the biocapacity demanded by the final consumption of all the residents of the country.
This includes their household consumption as well as their collective consumption, such as schools, roads, etc., which serve the household, but may not be directly paid for by the households.
Ecological footprint of production
In contrast, a country’s primary production Ecological Footprint is the sum of the Footprints for all resources harvested and all waste generated within the country’s geographical borders.
This includes all the area within a country necessary for the actual harvest of primary products (cropland, grazing land, forest land, and fishing grounds), the country’s infrastructure and hydropower, and the area needed to absorb fossil fuel CO2 emissions generated within the country (carbon Footprint).
The difference between the production and consumption Footprint is trade, shown by the following equation:
EFC = EFP +EFI − EFE
where EFC is the Ecological Footprint of consumption,
EFP - the Ecological Footprint of production, and
EFI - the Footprints of imported and EFE - exported commodity flows, respectively.
The world-average ecological footprint in 2007 was 2.7 global hectares per person (18.0 billion in total). With a world-average biocapacity of 1.8 global hectares per person (12 billion in total), this leads to an ecological deficit of 0.9 global hectares per person (6 billion in total).
If a country does not have enough ecological resources within its own territory, then there is a local ecological deficit and it is called an ecological debtor country. Otherwise, it has an ecological remainder and it is called an ecological creditor country.
Today humanity uses the equivalent of 1.5 planets to provide the resources we use and absorb our waste. This means it now takes the Earth one year and six months to regenerate what we use in a year.
Moderate UN scenarios suggest that if current population and consumption trends continue, by the 2030s, we will need the equivalent of two Earths to support us. And of course, we only have one.
Turning resources into waste faster than waste can be turned back into resources puts us in global ecological overshoot, depleting the very resources on which human life and biodiversity depend.