Earth Overshoot Day, also known as the Earth Debt Day is one of the less enjoyable days in the calendar. It is on this day that humanity’s consumption exceeds the amount of resources that our planet can supply in a year. Overshoot day comes sooner each year; we hit that day on August 19 in 2014. This year it was August 13, a full six days earlier.

Biological capacity reserves and deficits

Biological capacity, or biocapacity, is a way to measure an area’s ability to produce biological materials necessary for life, such as food, timber, textiles, and to absorb its waste, most notably carbon dioxide emissions. Deficits and reserves are determined by measuring an area’s capacity against its ecological footprint—the area required to support an ecosystem’s population.

Biocapacity reserves and deficit per country. Image via footprintnetwork

Biocapacity reserves and deficit per country.
Image via footprintnetwork

The Global Footprint Network estimated that humans would need the resources produced by just over one-and-half Earths to keep up with what we will use this year. And given the rate at which increasing global consumption and population has been exerting pressure on available natural resources, this day would eventually move to May 8, WWF says.

The Global Footprint Network estimates how much we consume, how efficiently we produce, how many people we are and how much the earth’s natural systems generate. “We can’t sustain such growth models and consumption patterns anymore”.

The Global Footprint Newtork says the largest proportion of the ecological budget is being used up by the vast amount of carbon being pumped into the atmosphere. However, it is not clear whether a sustained level of overuse is possible without significantly damaging long-term biocapacity, with consequent impacts on consumption and population growth. Japan would need 5.5 countries of its own size to meet its consumption requirements.

“It’s quite simple,” says Dr. Mathis Wackernagel of the think tank Global Footprint Network. “We look at all the resource demands of humanity that compete for space, like food, fiber, timber, et cetera, then we look at how much area is needed to provide those services and how much productive surface is available.”

His bottomline metaphor is that biological capacity is like your year’s salary, and Overshot day is the day you begin to live off debt because you’ve spent it all. Ideally, it should come on the last day of the year – December 31st. However, since 1970 when Overshoot day fell on the 23rd of December, it’s been steadily creeping up, and this year’s August 13 is the earliest recorded date.

Living today at the cost of tomorrow

Passing Earth Debt Day doesn’t mean there aren’t any more resources and we just tighten our belt and wait for next year. It means we’ll be using more than the Earth can actually give in a year, and there will always be interest.

Wackernagel cites struggling fisheries, accumulation of carbon dioxide in the atmosphere, soil erosion and deforestation as some of the consequences. Spiking food prices and diminishing water supplies worldwide, more costly and extreme weather events, and violent social conflicts such as the Syrian civil war, can also be seen as direct consequences of the increasing strain we’re putting on our planet’s dwindling resources.

The only way this game ends well for us is for developed countries to cut back on their overall resource consumption, switch to renewable energy sources, and recycle more.

Some countries “spend” their salary much faster than others. America and China for example, overshoot much faster than others, while large portions of South America always end the year with biocapacity to spare.

It’s also a question of income – Singapore, for example, exceeds its biocapacity on January 2nd, just after “payday”.

“It’s just a city,” says Wackernagel, noting that a small, densely populated island doesn’t have much capacity to begin with.

Some countries operate within their limits and don’t have overshoot days. That doesn’t mean Wackernagel lets them off the hook

“They are extremely resource rich,” he says of one country that isn’t overshooting. “That doesn’t mean they use their resources wisely, but that’s the privilege of being rich.”

Waste not, want not

Some countries such as Singapore, will never be able to not overshoot. Wackernagel doesn’t expect every country to reduce consumption enough as to never reach debt, but advocates a wiser use of resources for all and plans for the surpluses of some to balance out countries that overshoot.

He says that while the “metabolism of the Earth” is accelerating too fast for us now, he sees some positive signs.

“There are some international negotiations, like what’s going to happen in Paris,” he says, referring to the UN Conference for Climate Change, where nations will try to reach a global agreement for how to address the environmental issues we’ve been seeing recently.

“But it’s not enough to turn the boat around,” he adds, saying it might be time for a resource diet, so we won’t have to keep preparing for Overshoot Day earlier every year.

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