Report Suggests Global Population Could Top 12 Billion By 2100

Chuck Bednar for redOrbit.com – Your Universe Online
The global population could soar well beyond expectations in the years ahead, topping current projections that there will be nine billion men and women living on planet Earth by 2100 by more than two billion, researchers from the United Nations Population Division and several universities claim in a new study.
According to National Geographic’s Robert Kunzing, the study authors used a “probabilistic” statistical method to determine that there is an 80 percent chance the number of living people by the start of the next century will be somewhere between 9.6 billion and 12.3 billion (up from 7.2 billion currently).
Their work, said Damian Carrington of The Guardian, contradicts two decades of research suggesting the number of people living on Earth would peak at about nine billion people by the year 2050. The analysis shows that the challenges facing the world’s food supply, healthcare, and society as a whole may actually worsen in the second half of the century.
“The consensus over the past 20 years or so was that world population, which is currently around 7 billion, would go up to 9 billion and level off or probably decline,” corresponding author Adrian Raftery, a professor at the University of Washington, said in a statement. “We found there’s a 70 percent probability the world population will not stabilize this century. Population, which had sort of fallen off the world’s agenda, remains a very important issue.”
Raftery, who teaches statistics and sociology at the university, and his colleagues used the most recent UN population data that was released in July as the basis of their research, which was published online Thursday by the journal Science. They are said to be the first team of researchers to generate a population report using modern statistics, known as Bayesian statistics, to create better predictions by combining all available information into their projections.
Most of that expected growth will occur in Africa, where the current population of one billion is expected to quadruple by the end of the century due to a slower-than-anticipated decrease in birth rates in sub-Saharan Africa, the study authors said. Other regions are expected to experience less change.
The report suggests that there is an 80 percent chance the population in that continent will be between 3.5 billion and 5.1 billion people by the end of the century, while the population of Asia is expected to increase from 4.4 billion now to five billion in 2050 before beginning to decline. North America, Europe, and Latin America and the Caribbean are all projected to stay below one billion each, the researchers said.
Most predictions of global population growth were based primarily on future life expectancy and fertility rates, and previous techniques relied largely on what changes experts believed would take place in those trends, they noted. On the other hand, the new forecast technique uses statistical methods to combine government data and expert forecasts for such things as mortality rates, fertility rates and international migration.
“Population policy has been abandoned in recent decades. It is barely mentioned in discussions on sustainability or development such as the UN-led sustainable development goals,” Simon Ross, chief executive of the group Population Matters, told The Guardian. “The significance of the new work is that it provides greater certainty. Specifically, it is highly likely that, given current policies, the world population will be between 40-75 percent larger than today in the lifetime of many of today’s children and will still be growing at that point.”