The world could have another billion people in thirteen years

The United Nations just released updated population projection figures, and it looks like our world is going to get more crowded.

The UN estimates that the current world population is about 7.3 billion. Based on their main middle fertility projections, the UN expects that we will hit 8.3 billion — one billion more people — by 2028, with the population rising to 11.2 billion by 2100.

Any projection into the future has uncertainty: Fertility rates could be different than expected, or developments in agricultural and medical technology could dramatically change the human life span. To somewhat account for that uncertainty, the UN projections include a few alternate scenarios.

If fertility ends up being higher than predicted, the Earth's population could rise as high as 16.6 billion by the end of this century, more than twice as large as the current population. Meanwhile, if fertility rates are lower than expected, the population could max out around 8.7 billion in the 2050s and then decline back to around the current level by 2100.

Here's the UN's historical estimates for the global population through 2015, and projections based on low, medium, or high future fertility:

world population projection

(Business Insider/Andy Kiersz, data from United Nations)

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