Earth Overshoot Day marks the date when humanity’s demand for ecological resources exceeds what the Earth can regenerate in that year. In 2021, it fell on July 29. In other words, after just seven months, we had already used up all the planet’s renewable resources and started creating an “ecological debt.”
Each year, Overshoot Day arrives earlier. In 1970, it fell on December 30. Since then, the date has crept forward relentlessly. The year 2020 was one of the rare exceptions: the overshoot came later than usual—on August 22 (in 2019 it was July 29)—due to the pandemic, which slowed the global economy.
How Earth Overshoot Day is measured
Just like a bank statement tracks deposits and withdrawals, the Global Footprint Network calculates humanity’s demand and compares it with the supply of resources and services provided by ecosystems. These calculations form the basis for determining Earth Overshoot Day.
On the supply side, biocapacity refers to the biologically productive land and sea area of a city, state, or nation—including forests, pastures, croplands, fishing grounds, and built-up areas.
On the demand side, the ecological footprint measures a population’s need for plant-based food and fiber, livestock and fish products, timber and other forest products, space for urban infrastructure, and forest area required to absorb its carbon dioxide emissions from fossil fuels.
Who consumes the most?
Unsurprisingly, high-income countries with limited natural resources are the largest consumers: 14% of the world’s population uses 52% of available resources. If everyone lived this way, humanity’s resource consumption would soar from today’s 173% (as if we had 1.7 planets) to 367% of global biocapacity per year.
Many countries reached their national Overshoot Day well before July 29. In Italy, for instance, it was May 13, one day earlier than the previous year—despite the lingering effects of the pandemic.
#MoveTheDate
The Global Footprint Network emphasizes that the current trend does not have to be our destiny. Several solutions can help guide development toward sustainability. Cutting global food waste by 50% would push back Overshoot Day by 13 days. Adopting already available sustainable technologies in buildings, industry, and power generation could move it by at least 21 days—without reducing productivity or comfort. Reducing carbon dioxide emissions by 50% would shift Overshoot Day by as much as three months.
In the lead-up to COP26, the major international climate summit held in Glasgow from November 9–20, 2021, bringing together over 30,000 delegates (including heads of state, climate experts, and activists), the Global Footprint Network will dedicate 100 days after Earth Overshoot Day 2021 to presenting on its website examples of solutions already being implemented around the world—urging us to replace business-as-usual practices that we can no longer afford.
Sources: Etica Sgr, Overshootday.org
