We've written quite a bit about the concept of ecological footprints, but this graph, from the Footprint Network, pretty handily sums up the whole situation.
As they say:
The Earth's biologically productive area is approximately 11.2 billion hectares, or 1.8 global hectares per person in 2002 (assuming that no capacity is set aside for wild species). Global hectares are hectares of biologically productive area with world-average productivity. This standardised measurement unit, or 'ecological currency,' makes comparisons of demand and supply possible across the world.
In 2002, humanity's demand on the biosphere, its global Ecological Footprint, was 13.7 billion global hectares, or 2.2 global hectares per person. Thus in 2002, humanity's Ecological Footprint exceeded global biocapacity by 0.4 global hectares per person, or 23 percent. This finding indicates that the human economy is in ecological overshoot: the planet's ecological stocks are being depleted faster than nature can regenerate them. This means that we are eroding the future supply of ecological resources and operating at the risk of environmental collapse.
It's not happy news, but tools like ecological footprinting are giving us understanding of the basic funamentals of our planetary situation, and insight into the big picture is, itself, a tool.









