Ellen Phiddian
Cosmos science journalist
Today is Earth Overshoot Day, the day of each year when humanity uses more resources than the planet can regenerate in a year.
Calculated by the Global Footprint Network, the day represents people exceeding Earth’s “biocapacity”: the ability of an ecosystem to generate resources in a sustainable way.
As a whole, the planet is exceeding this biocapacity, by over-drawing on ecological systems, and creating too much waste (most of which is atmospheric carbon dioxide).
In fact, humanity this year has drawn on about 1.7 Earths worth of resources.
The Footprint Network uses data drawn primarily from the United Nations to calculate both biocapacity and humanity’s demand (called our “ecological footprint”).
They use roughly 15,000 data points per country per year, including factors like greenhouse gas pollution, food and resource growth, and physical space used.
This year, the August 2 Date of Earth Overshoot Day is 8 hours later than the 2022 date, representing a small slowdown.
But last year, Earth Overshoot Day was marked on 28 July. The 4 days’ improvement didn’t come from a slowdown in the way humans are using resources, it came because the Footprint Network has updated its datasets.
“The accounts are updated every year, with a new edition,” Dr Mathis Wackernagel, founder and president of the Global Footprint Network, tells Cosmos.
“All historical results are recalculated using the newest edition. Changes are typically small.
“This year, the impact of better data sets led to a change in 2% for global results, but that small change still shifts Earth Overshoot Day by 4 days.”
So, while it looks like humanity’s doing much better, the real difference is only slight.
Wackernagel says that this is partly because greenhouse gas emissions, which currently account for 60% of our ecological footprint, have increased more slowly than in the past.
But the network isn’t celebrating this tiny slowdown: it’s nowhere near enough to indicate that the trend is reversing.
The Footprint Network has calculated past Earth Overshoot Days, going back to 1971.
In 1971, according to the latest data, humanity exceeded the planet’s resources on December 25. Consumption of resources was nearly in balance with what could be sustainably produced.
The date has steadily, but not completely uniformly, moved earlier in the year since then – the 2020 pandemic lockdowns shunted the date back a fortnight, to August 16, for instance.
Individual countries also have different Overshoot Days. If everyone lived like Australians, for instance, Earth Overshoot Day would be 23 March.
The US and Canada share an Overshoot Day on 13 March, while China’s is 2 June and Indonesia’s is 3 December. Qatar’s is the earliest, on 10 February.
Roughly 50 countries don’t have Overshoot Days, because their citizens don’t use more resources than the Earth can regenerate. These countries include India, the Philippines and Sudan.
The Footprint Network identifies five broad areas for moving the date back again: city planning, decarbonising energy, reducing food inefficiency and waste, conserving and restoring nature, and addressing population growth.
Each of these on their own have the potential to move the day back by weeks.
But, based on UN prediction for population and consumption, the Global Footprint Network currently estimates that we’ll need two Earths to satisfy our demands by 2030.