What does the Ecological Footprint tell us?
Humanity's Ecological Footprint can be illustrated in numbers of planets, where one planet equals the total biocapacity of the Earth in any one year. Since the late 1980's, we have been in 'overshoot': currently the Ecological Footprint exceeds the Earth's biocapacity by about 30 per cent. In other words, it now takes about one year and four months for the Earth to regenerate what we use in a single year.
The Ecological Footprint illustrates that, as a global community, we currently need about 1.3 planets to meet our average consumption levels.
The average global Ecological Footprint is 2.7 global hectares per person, while there are only 2.1 hectares of biologically productive area per person available on the planet. This is called 'overshoot'.
Much like spending more money than you earn, it is possible to exceed ecological limits for a while, but this "deficit spending" leads to the destruction of ecological assets on which our economy depends, such as depleted groundwater, collapsing fisheries, Carbon dioxide (CO2), accumulation in the atmosphere, and deforestation.
The main contributor to overshoot is carbon dioxide emissions. We are emitting this greenhouse gas faster than the planet can re-absorb it, so it is building up in the atmosphere – contributing to climate change. While climate change may represent the most alarming symptom of overshoot, it also offers the greatest opportunity for change; virtually every action we take to reduce climate change also reduces overshoot, and vice versa.
Earth Overshoot means that we are reducing the ability of the earth's land and water to support humans and other species into the future. If we conquer climate change without depleting other natural assets, we can rebalance our Earth budget. Learn more about other global effects of overshoot.
In 2008, the Earth went into Overshoot on Tuesday 23 September – the day we started using all the resources nature will generate this year. To learn more about Earth Overshoot Day, visit Global Footprint Network.
Download a presentation by Mathis Wackernagel (Microsoft PowerPoint file, 17649KB or 17.65MB)
Download a DVD of the Ecological Footprint, featuring Mathis Wackernagel, and introducing the concept of Ecological Footprint.