Today is Earth Overshoot Day. Happy Earth Overshoot Day! Except, well, we don't much feel like celebrating.
That's because Earth Overshoot Day is the day each year when we've consumed natural resources at a rate beyond which our planet can replenish, and have produced more waste than can be reabsorbed, according to the Global Footprint Network, a think tank based in the US, Switzerland, and Belgium.
The holiday was originally conceived of by Andrew Simms, of the U.K. think tank New Economics Foundation. This year, it falls on August 20, two days (or three, depending on the calculations) earlier than it came last year, following a relatively steady trend since 2001: falling about three days earlier each year. (Humanity first went into overshoot in 1970; that year, Earth Overshoot Day fell on December 29.)
The cause for our unsustainable consumption is multi-pronged. We have a growing population (now at more than 7.1 billion, and according to the World Popular Clock, the net gain is one person every 13 seconds) with growing demands for products and services that create more waste, and use more resources. At our current rate of global consumption and waste production, the level of resources required to support us is about 1.5 Earths. The Global Footprint Network says we are on track to needing two Earths before we reach the middle of the century.
Today, according to the Global Footprint Network, more than 80 percent of the world's population lives in countries that use more than their ecosystems can renew. Some of the bigger offenders: Japan consumes 7.1 Japans worth of resources; Italy, four; and Egypt, 2.4. China's ecological footprint is the largest (they would need 2.5 Chinas to accommodate their population) - though the per capita footprint is smaller than many European or North American countries.
To calculate the date, the Global Footprint Network figures out how many days of a particular year the Earth's biocapacity can provide for the total ecological footprint. So, world biocapacity divided by world ecological footprint times 365 equals Earth Overshoot Day. The think tank calculates biocapacity by looking at the amount of productive area (both land and sea) available to provide resources and to absorb wastes under the constraints of current technology and management practices. A country has an ecological reserve if its footprint is smaller than its biocapacity, and likewise, if its footprint exceeds biocapacity, it is an ecological debtor.
The Global Footprint Network notes that the date is an approximation. The precision of the exact date is limited by aggregated country datasets, but still shows that humans are using the Earth at a rate that is unsustainable, year after year.