Tanzania will be a major population growth driver, according to the UN. Photo: Rémi Kaupp/Flickr
The United Nations has just released its latest projections for how many humans are going to be running around this small planet, revising upwards forecasts for population growth by mid century. According to the 2012 revision of World Population Prospects, assuming the UN's medium growth scenario, by 2050 there will be 9.6 billion people on Earth.
That's an increase of roughly 300 million people from previous forecasts. The revision is based upon higher-than-expected fertility levels in a number of high-growth countries, due in part to better data becoming available.
As this piece is written there are slightly over 7.12 billion people on Earth, a number that's growing by over 100,000 people per day. The last century has seen exponential population growth. The world population was just 2 billion in 1927, which doubled by 1974. The latest UN figures have us passing 8 billion people just before 2025—yet another doubling of human population in just half a century.
The growth demographics reflect our changing world. In 2050, when the UN predicts our world population will be nearing 10 billion, 8.2 billion of those people will live in what are currently considered to be developing nations. The population of wealthy nations will remain more or less stable throughout the entire time period, with around 1.3 billion people in total.
By 2028, the forecast shows, the population of India will catch up with that of China, with each nation having roughly 1.45 billion people. After this, however, the scenario changes markedly. Through the end of this century the population of India is projected to grow much more slowly, with the nation hitting 1.5 billion people. China, on the other hand, is projected to show a decline, falling back to 1.1 billion people by 2100.
At the same time, Nigeria's population is expected to skyrocket, approaching that of China's by 2100, with Indonesia, Tanzania, Pakistan, the Democratic Republic of Congo, Ethiopia, and Niger each having over 200 million people.
That all but two of those nations is in Africa is significant. Over half of all total population growth between now and 2050 is to occur there, rising from 1.1 billion today, to 2.4 billion by 2050 and 4.2 billion by 2100. This happens even if, as predicted, fertility drops from an average 4.9 children per woman today to 2.1 per woman by the end of the century.
These numbers are certainly striking, but they represent a medium population growth scenario. Under a low growth scenario, the UN forecasts 8.3 billion people by 2050, whereas, under a high growth scenario there will be an even more claustrophobic 10.9 billion people.
As for the impact on the planet of all this (and, indeed, whether such population levels can be even reached without ecological collapse in many areas), that's a hugely complex subject, beyond the scope of what we have length to discuss here.
What is clear though is that at the most basic level current levels of resource consumption, even averaged across all nations, even with wildly disparate levels of consumption, are not sustainable in the long run.
According to the Global Footprint Network, humans are using the equivalent of 1.5 Earths to provide resources and absorb our waste products—meaning that it would take 18 months for the planet to regenerate all that we consumed in the previous year. Under a moderate business-as-usual scenario that rises to nearly 3 planets by mid-century. By using up resources faster than they can be regenerated, we are destroying the ability of the planet to support life.
Though that doesn't mean the end times are nigh—at least not until 2050—it does call into question assumptions about what are considered normal levels of resource consumption in wealthy nations. Even calling wealthy nations "developed" ought to be questioned, as the current standard for developing nations to aspire to is unsustainable.
If we are to hold the notion of relative equity between all humans to be a laudable goal, then with 9.6 billion people on the planet, individual resource consumption in currently wealthy nations must fall to accommodate growth elsewhere. It's either that, or we must abandon notions of aspirational equity among nations, or worse, prepare ourselves for some serious, potentially violent, competition over basic resources.