On the 13th August this year, the Global Footprint Network announced that it was Earth Overshoot Day, a whole 6 days earlier than in 2014. But what does this mean?
Imagine a lake full of fish. If you only catch some of the fish, there are enough left to breed and replace the stock for the next year. The number of fish may even increase. But if you catch too many, the population will be unable to replace all of those lost and eventually there will be no fish left in the lake. This is how it is with the Earth’s natural resources, from fossil fuels to timber, animal and fish stocks. Earth Overshoot Day doesn’t mean that there are no resources left for the rest of the year, it means that we are using far more than the Earth can replenish and replace. This has been the case since the early 1970s, and Earth Overshoot Day is happening earlier and earlier every year as demand increases.
It’s not just that resources are being used faster than they can be replaced, of course; carbon emissions are increasing as well. When forests are cut down to make way for grazing land, for crops, for housing and so on, they can no longer absorb the excess carbon dioxide in our atmosphere and turn it into oxygen. This means that the carbon dioxide, a greenhouse gas, accumulates and increases the rate of global warming and climate change.
The date of Earth Overshoot Day is worked out using a relatively simple formula. The amount of ecological resources available in a year is divided by the demand for those resources, and then multiplied by 365. It’s not an exact calculation but it’s a good indication of just how much of our planet we’re over-using. Many countries use more natural resources than their own ecosystems are able to provide. For example the UK, a small but heavily populated and industrialised country, uses 3 times as many resources as its ecosystem can supply.
Every year we’re using up more and more of the Earth’s resources. From using only three quarters of the planet in 1961, we began exceeding the renewable rate in the early 1970s. In 2000 Earth Overshoot Day was in October, but just 15 years later we’ve reached that point in August. It’s estimated that unless the world’s governments work together to reduce the impact we’re having on the Earth, we will be using 2 whole planets worth of resources by 2030.