The U.N.’s latest World Population Prospects report projects that India will surpass China as the world’s most populous country by 2022, six years earlier than previously expected. China has about 1.38 billion people to India’s 1.31 billion, and both countries will hit 1.4 billion in seven years. After that, India’s population will continue to grow for several decades while China’s is expected to remain flat until the 2030s, when it will start to decline. The U.N.’s revision comes just a few days after reports that China is planning to change its longtime “one-child policy” to a nationwide two-child policy, a shift that is unlikely to significantly impact the country’s graying population.
The U.N. reports that the world population is now about 7.3 billion, and 60 percent of those people live in Asia. That’s a billion-person increase over the last 12 years. The growth is slowing due to falling fertility rates, particularly in more developed countries, but the U.N. still expects 8.5 billion people by 2030, 9.7 billion in 2050 and 11.2 billion by 2100, though it notes that those numbers are heavily dependent on fertility trends. (Some demographers believe the world population will peak as soon as the 2050s, but that’s still a fairly controversial position.)
Fertility rates are falling virtually everywhere in the world, but much faster in Europe and East Asia. Most of the population growth going forward will be in Africa. About half of the people born between now and 2050 will be African, and after that, the continent will be the only region of the world experiencing major population growth. Nigeria, Africa’s most populous country, is expected to overtake the United States as the world’s third-largest country around 2050.
Most of the U.N. report is good news—people are living longer than ever, childhood mortality is down almost everywhere, and populations are growing less explosively than in years past. But obviously, even with more manageable growth rates, feeding 9 billion to 11 billion people on a warming planet will be a daunting challenge in the coming century. And the fact that the vast majority of the growth is happening in the world’s poorest countries will likely add to the strain of what is already an unprecedented number of migrants around the world.