As of today, we humans have used as much from nature in 2016 as our planet can renew in a whole year. Nothing will seem to change for many of us between today and tomorrow, but collectively we are draining Earth’s capacity to provide. Overshoot Day is a red light warning of trouble ahead — and it is flashing five days earlier than it did last year (Aug. 13); eleven days earlier than the year before (Aug.19).
Earth Overshoot Day is devised by Global Footprint Network, an international think tank that coordinates research, develops methodological standards and provides decision-makers with a menu of tools to help the human economy operate within Earth’s ecological limits.
To determine the date of Earth Overshoot Day for each year, Global Footprint Network says on its website, the think tank calculates the number of days of that year that Earth’s biocapacity suffices to provide for humanity’s Ecological Footprint. The remainder of the year corresponds to global overshoot.
Less for Us to Use
“When overshoot day arrives, it means we have spent all the interest on the planet’s ecological bank account and are now dipping into the capital,” explains Stuart Pimm, Doris Duke Professor of Conservation Ecology at Duke University’s Nicholas School of the Environment (and emeritus member of the National Geographic Society’s Committee for Research and Exploration). “That is, we’re depleting what our planet does for us, so year after year, there is less for us to use. Less forest, fewer fish in the ocean, less productive land — burdens that fall disproportionately on the world’s poor,” he says.
Earth Overshoot Day is calculated by dividing the planet’s biocapacity (the amount of ecological resources Earth is able to generate that year), by humanity’s Ecological Footprint (humanity’s demand for that year), and multiplying by 366, the number of days in 2016: (Planet’s Biocapacity / Humanity’s Ecological Footprint) x 365 = Earth Overshoot Day.”