Imagine an accounting system for the resources of the earth. The earth provides us with the natural resources needed to sustain life and industry, but our use (or waste) of those resources can also reduce the capacity of the earth to provide them.
The Ecological Footprint estimates – in land area – the human demands on the biological capacity needed to meet those demands and absorb the CO2 generated by humans in the process. To pick some extremes, a verdant tropical country with low population density would be expected to have a smaller Ecological Footprint than a highly industrialized and populous desert nation.
For example, compare Bolivia and Belgium below. The biocapacity of Bolivia is greater than the biological demand of its people. This means that the demands on Bolivia each year are more than met by the resources of Bolivia. That’s good, but note the troubling decline in biocapacity as primary rainforest is lost.
In contrast, people in Belgium have a high demand on the resources of their nation – much higher in fact than the land area of the nation can sustain. Belgians have a much larger Ecological Footprint than do Bolivians.
Globally, we look a lot more like Belgium than we do like Bolivia. That’s the logic behind Earth Overshoot Day. To understand this indicator a bit better, check out the linked video:
Today, August 13th, is the earliest calendar date at which it is estimated that global demand for resources is in excess of what the biocapacity of the earth can provide us. In 15 years, that date has crept earlier and earlier each year, from October in 2000 to August today. We now are running a deficit the equivalent of 1.6 earths to sustain the size of our global Ecological Footprint, every year.