One Degree wrote:http://www.footprintnetwork.org/en/index.php/GFN/page/earth_overshoot_day
This is a measure of our "Global Footprint," which is not just when "we have used up the renewable resources the earth can replenish in a year," but rather
its ability to replenish the planet’s resources and absorb waste, including CO2
http://www.footprintnetwork.org/images/ ... eneral.pdfMost of the "footprint" in the report comes from Carbon, and its pollution-causing effects. Without the carbon, or with reduced carbon, we would or could be well below the line of "world capacity."
http://www.footprintnetwork.org/images/ ... Report.pdfA more useful measure of the earth's ability to support more people would be to take away the measure of absorbing carbon, and then we could better see how much of our renewable resources we are consuming each year. This is especially true as we are generally heading towards getting away from using carbon as an energy source, which will greatly reduce this burden on the environment. Again, this is a look at the environment as a whole, not just what percentage of the world's natural resources we are using each year. This also doesn't take into account improvements in technology that, for example, leads to less land used to produce more food, as the data in the study is based upon land use, not actual resource totals.
One Degree wrote:http://www.foreignaffairs.com/articles/139832/carter-roberts/the-day-the-earth-ran-out
This article cites the first as its source, so the same problems apply.