When Will Earth Reach Maximum Capacity?

When Will Earth Reach Maximum Capacity?

This old world of ours sure is a lot more crowded than it used to be. And it's becoming more so, every day. According to UN estimates, as of 2019 there are 250 babies born every minute, while the world population is currently growing at a rate of around 80 million people per year. There are 7.6 billion people living on the planet, with almost 40% of them residing in either China or India. Regardless of what nation or region one calls home, though, it's quite possible that sooner or later the Earth will run out of space. However, the biggest strain isn’t actually on physical living quarters, but on the planet’s resources – which are becoming increasingly exhausted thanks to overpopulation.

So, is there an unmanageable upper limit to which we’re all marching? Is there some kind of ominous cut-off point before the planet just gives up as our host, unable to sustain us any longer? When will Earth reach maximum capacity?

While there’s obviously no definite, to-the-minute answer – as there are just too many variables involved – there are plenty of important issues to consider. Clearly, the sheer number of people alive is a key starting point, but factors like population spread and how we do (or don’t) share our fuel, food and various other consumables also come into play. Some argue that our planet’s already at breaking point, but many of the concerns boil down to the inefficient lifestyle choices taken (by some) as part of the modern world. For example, roughly 150,000 tons of food is thrown out every single day – in America alone. And statistics such as those trigger investigations carried out by non-profit organizations like the Global Footprint Network, which found that in 2018 we’d already used one year’s worth of global resources by only August 1st. The date has been christened ‘Earth Overshoot Day’, and it’s been encroaching further and further into the calendar year ever since the early 1980s.

In general, first world countries tend to devour the majority of the world’s resources. This imbalance is highlighted via the country-by-country Overshoot Day statistics, which show when the Earth would surpass its yearly quota if everyone lived akin to any given nation. In 2018, the USA had used its resources by March 15th; Canada, by March 18th; Russia, April 21st; Germany, May 2nd; the UK, by May 8th; and China, by June 15th. Of the Countries included in the study, only Kyrgyzstani, Moroccan or Vietnamese lifestyles would allow for the Earth’s resources to stretch into the last two weeks of December.

Similar statistics are found elsewhere. The 2018 ‘Living Planet Report’, conducted by the WWF, found that Earth is losing its biodiversity at rates comparable to previous extinctions, thanks largely to human impact. Wildlife populations have fallen by up to 60% since the 1970s, and it’s predicted that by 2050 only one tenth of the planet will be considered even reasonably free from human-made problems. Back in 2012, researcher Tim De Chant calculated – based again on Global Footprint Network statistics – that we’d need the equivalent of 4.1 Earth’s worth of resources if everyone lived like an American. That figure rose to 5.4 Earths for the United Arab Emirates. So, going by those numbers, our planet reached maximum capacity a long time ago.

What’s becoming apparent, though, is that many of the most damning claims are linked to our own overconsumption. Which suggests that, should humankind somehow lessen its output and impact, then the Earth would be able to support even more of us. Which is true. But, there still has to be an upper limit – right?

A 2004 study titled “Reconsidering the Limits to World Population”, which took into account more than 60 previous world population estimates, found that an average ‘maximum capacity’ was 7.7 billion – so very close to what we’re currently at. However, the study also found grounds to suggest that the upper estimate could soar as high as 98 billion, in exceptional circumstances.

That said, most experts argue that the larger population projections are only really achievable through technologies that haven’t been invented yet. Perhaps, one day, we’ll be able to manufacture compact, highly nutritious, possibly tasty, but most importantly affordable and environmentally friendly foods, and we’d be able to mass produce and distribute them evenly across all countries. Maybe, in the near-future, we’ll find breakthroughs that can quadruple our farming yields, while halving our ecological footprint. We’ve already made significant steps towards the use of renewable energy sources, and twenty-first century buildings are increasingly built with their efficiency in mind. But, still, the heady highs of 98 billion feel almost inconceivable.

The more readily quoted number, and perhaps a more realistic target, is 10 billion. That’s around 2.5 billion more people than there currently are. Scientists generally cite this figure as Earth’s maximum capacity because a) when the amount of farmable land across the world is calculated, that’s how many people it could support (diet-dependant)… and b) because the United Nations reckons that, by 2100 and based on current growths and declines, the global population could naturally peak at 10 (or even 11) billion. The number is dependent on some important factors, though… Namely a reduction of the average family size, and an increase in those adopting a more plant-based diet. In terms of population and global resources, vegetarianism encourages a more efficient use of crops and grains – with produce going directly onto our own plates, without the need for feeding up livestock.

The UN’s landmark year of 2100 is also arrived at thanks in large part to declining birth rates around the world. In predominantly western cultures, population growth has been steadily decreasing since the 1960s. In the early '70s, women had, on average, 4.7 children. But, by the mid-2000s, the average had fallen to 2.6. In some countries – including Japan, most notably Andorra, and Greece – the natural population growth is even in the negative right now, meaning more people are dying than are being born. Given that average life expectancy figures are also increasing around the world, these types of situations are still fairly rare; a demographic anomaly. Naturally, though, in those specific countries at least, this means that the population is falling (although it should also be said that natural population growth numbers don’t take into account the effects of immigration).

All in, the 10 billion people figure is still held as the upper limit for global population. Yes, there are arguments based on potential future technologies that push it higher, but the general consensus crowds around 10 billion. Once we surpass it, and for as long as humanity’s tendency toward inefficient overconsumption continues, then we’re stretching our resources beyond what’s currently feasible. And, that’s when Earth will reach maximum capacity.