The human population of planet Earth will likely exceed 11 billion by 2100, according to an analysis being presented today at the 2015 Joint Statistical Meetings by John R. Wilmoth, director of UN's Population Division. The upshot is that, no, human population growth will not chill any time this century, barring unexpected fertility declines in regions of sub-Saharan Africa with still-exploding birth-rates.
The odds of that happening, according to Wilmoth, are about 23 percent.
More precisely, the median estimate is 11.2 billion people, which, while still a lot of fucking people, isn't as bad as some worst-case estimates offered by the UN circa 2010. These had the world population more or less increasing as it did through the 20th century without slowing, leaving us with 16 billion in the same timeframe.
The Population Division's current median estimate is in the neighborhood of its 2010 median estimate, but very low or very high population possibilities are still possible, as you can see from the graph below. Mostly, things are going about as previously predicted, which at least means that we haven't suddenly changed trajectory toward the upper-bound 16 billion estimate, which would all but guarantee the planet's future as a teeming hellscape of global resource wars, famine, and worse. Though, it also hardly precludes that future, which we're seeing some vivid previews of now, with a mere 7 billion.
The lowball estimate would be nice: 6 billion. But don't count on it. The Population Division estimates that the population of Africa will increase from the current 1.2 billion to between 3.4 billion and 5.6 billion people. Fertility rates on the continent have generally declined in recent years—though nothing like the declines seen pretty much everywhere else in the world—but the current report notes that this trend has somewhat stalled. For example, while the highest predicted, but most unlikely fertility rates in Nigeria would result in a population spike from around 100 million to over 750 million by the end of the century, the most likely outcome (with a 90 percent chance) is an increase to around 450 million people. This is still 2.5 times larger than the country's current population.
The UN's current best guess for Asia is a population increase from 4.4 billion to 5.3 billion by the middle of the century, with a decline to 4.9 billion by 2100. Many Asian regions are expected to soon face a curious inverse population explosion, where the ratio of older and elderly people to young people is unbalanced in the opposite direction. This is a situation with its own set of problems.
The situation is definitely a bit different (read: better) than the '90s heyday of the zero population growth movement. Even the Zero Population Growth organization has rebranded itself as "Population Connection" and advocates for the somewhat more friendly or at least abstract goal of "population stabilization." But things are really and truly bad in many parts of the world, which is easy to blame on population, and, as such, is easy to not blame on global wealth inequality. Less people always seems like a great cure-all, but it only matters if resources are being distributed equitably in the first place.