The world’s population may shrink after 2040, according to the Club of Rome

The world’s population may not be growing as far as previously thought. According to a new calculation mandated by the Club of Rome, the world’s population will peak at 8.8 billion people in 2046 and decline thereafter. The peak could be even lower, at 8.5 billion people in 2040, if extra investments are made in poverty alleviation and education in countries where the birth rate is now high. Both of these scenarios are well below the United Nations’ forecast, which last year predicted a peak of 10.4 billion people in 2080. At the moment there are about 8 billion people on earth.

The differences are due to different calculation methods. The UN extends trends in births and deaths from the past into the future, a well-known demographic approach. Earlier, other demographers thought this was too limited. They also take into account access to education and contraception because these influence the number of children a woman has. As a result, a number of alternative forecasts are lower than those of the UN. Thus appeared in 2020 in The Lancet a study that predicted a peak of 9.7 billion people in 2064.

In this new study, particular weight is attached to people’s income. Not just education and contraception, but a whole range of lifestyles are linked to the lower fertility rates, the researchers argue. Income is a good indicator for this.

Later in the century, the difference between the two scenarios in the new study becomes more striking: a peak of 8.8 billion people in 2040 leads to 7.4 billion people in the year 2100. In the scenario with additional investments and a peak of 8 .5 billion people in 2040, the line will fall faster, then there will be 6 billion people in 2100. This is because changes in demographics become visible with a delay. “How many children a girl born today will have in the 2040s or 2050s is strongly influenced by the level of education, health care, contraception, jobs, economic security and empowerment to which she will have access from now on,” the researchers write.

The researchers have a message with their two scenarios, which is in line with previous analyzes by the Club of Rome: with fewer people on earth, it is easier to stay within the limits of what the earth can handle. “But our models also show that the biggest driver behind the current problems is not overpopulation, but the overconsumption of the richest ten percent,” the researchers write.

“The Club of Rome has a good reputation for presenting coherent analyses. This is an interesting exercise, but in a model in which there is a lot of information and everything is interrelated, the uncertainty also increases explosively,” says Leo van Wissen of demographic research institute NIDI. “Is it certain that these are precisely the factors that cause the decline in the fertility rate? How will each of these factors develop in the coming years? And how do they interact with each other?”

“The UN model is a simple approach, there is nothing explanatory in it,” says Van Wissen. “The UN cannot do otherwise, as soon as you start working with explanatory factors, all sorts of things also start politically. The UN model is modest in what it can do, but it is clear about the margin of uncertainty. This comes close to the forecasts that mainly include education. I myself put my money on one of those forecasts. But this new research does show what is possible when all signals are green. I think that is an important message to politicians.”