The total global population count will reach somewehere between 9.5 and 13.3 billion by the end of the century, the United Nations Population Division estimates. The world’s current population is 7.3 billion people.
The projected figures suggest the world population will not cease to grow this century, short of unprecedented fertility declines in those parts of sub-Saharan Africa that are still experiencing rapid population growth. The UN estimated the probability that world population growth will end within this century to be only 23%.
The projection was announced by John R. Wilmoth, director of the United Nations Population Division, during a session on demographic forecasting at the 2015 Joint Statistical Meetings (JSM 2015) in Seattle.
Demographic Change Models
Wilmoth told the audience that according to models of demographic change derived from historical experience, the United States population is projected to add 1.5 million people per year on average until the end of the century, driving the current count of 322 million people up to 450 million.
The big hitter for global population growth will be the increase in the population of Africa. The continent’s current population of 1.2 billion people is expected to rise to between 3.4 billion and 5.6 billion people by the end of this century. Africa’s population growth is due to persistent high levels of fertility.
Wilmoth said Asia, with a current population of 4.4 billion, is likely to remain the most populous continent, with its population expected to peak around the middle of the century at 5.3 billion, and then to decline to around 4.9 billion people by the end of the century.
Developing countries with young populations but lower fertility, such as China, Brazil and India, could face the prospect of significant population aging before the end of the century. These countries, the projection suggests, should invest some of the benefits of their demographic dividend in the coming decades toward provisions for the older population of the future such as social security, pensions and health care.
In the United States, the median age of the population is expected to increase from today’s 38.0 years to 44.7 years in 2100.
Photo: Kenneth Lu/flickr