The world population is expected to stabilize towards the end of the century, but perhaps even earlier. A trend that will make it possible to limit the exploitation of the planet's resources. But there are those who fear the effects of an overly aged humanity with few children.
It took tens of thousands of years to reach one billion people on Earth, but only 200 years to go from one to nearly eight billion today. The great challenge, we read in an interesting article by Giuliana Coccia in Futura Network it will be able to guarantee food and a dignified life to these eight billion, without aggravating global warming. "It is a reminder of our shared responsibility to take care of our planet and a time to reflect on where we still fail to meet our mutual commitments," said UN Secretary General António Guterres.
A growing population tends to consume more and more, not only in terms of volume but also of composition of consumption, especially energy and food. By improving living conditions, developing countries (where population growth is more concentrated) increase the demand for energy and extend their diet to foods (such as meat) whose production requires higher emissions. Therefore, as stated in a UN report on demographic trends, "To address the needs of individuals more sustainably, policy makers need to understand how many people live on the planet, where they are, how old they are and how many people will come after them."
Every two years the UN publishes a report with estimates of world population growth, which have so far been rather faithful to reality. But two years ago the Institute for Health Metrics and Evaluation, a research center at the University of Washington, developed new forecasts that were decidedly lower than those produced by the United Nations in 2019, arousing interest and criticism.
Subsequently, Coccia recalls, the UN also updated its forecasts with a downward adjustment, publishing a report in 2022 (the Revision of World Population Prospects) which examines the current and future situation of the world population.
Dynamic but slowing growth
The dynamics of population growth (on average 0.04% per year) was very slow until 1700, when the very high infant mortality contrasted the high fertility. As health conditions improved and infant mortality fell, the situation changed rapidly. In the last century, the world population has grown at an ever-increasing speed, only to slow down since the 1950s.
Today the population is increasing on average by 1% per year: a growth rate that is still fast, in the sense that every year 140 million people are born and 60 million die, for an increase of about 80 million individuals per year. According to the latest forecasts of the UN Department for Economic and Social Affairs, the world population will continue to increase, reaching 8.5 billion individuals in 2030, 9.7 billion in 2050 and 10.4 billion in 2080, before stabilizing at 10.9 billion people in 2100. The population growth rate will continue to decline, reaching 0.1% in 2100.
This anticipated decline in the future world population is due to an update of the fertility forecasts: the number of children each woman has in her lifetime is currently equal to 2.3, but it is estimated that it will drop to 2.1 in 2050. Because fewer children will be born, rich countries will mainly increase the population thank you to immigration, which in the last 20 years they have exceeded the number of births (80.5 million) compared to deaths (66.2 million). The situation in poor countries is different, where, at least in the short term, births - higher than deaths - will still be the main reason for the increase in population.
When population growth stops
The anxiety about the demographic decline has never really faded. On the occasion of a conference held in May, Elon Musk, CEO of Tesla, said humanity needs to "at least keep our numbers" and sounded the alarm, stating that "Population collapse due to low birth rate is a much greater risk to civilization of global warming ". But many scholars reject the idea that there may be a "collapse of the population“.
"Although some countries have declining populations due to lower than replacement fertility, overall the world population continues to grow and probably will (albeit at increasingly slower rates) until the end of the century," he said. Alice Reid, director of the Cambridge Group for the History of Population and Social Structure. This is partly due to the so-called "demographic momentum“, Which means that even when women have fewer than two children on average, populations continue to grow because large cohorts of already born women contribute to large numbers of births.
"Both the decline in fertility and the decline in population should be celebrated rather than feared," Reid said, adding that lower birth rates are often linked to higher education for women, greater gender equality and standards of higher life. Infime concluded "The aging of the population poses challenges to society, but the answer is not the increase in birth rates, if people stay healthy longer in their lives, they can continue to work longer".
Rather than simply encouraging childless people to start having children, societies need to start adapting to a wider range of lifestyles, she says. GunnarSkirbekk (Norwegian philosopher). There is evidence that societies with stronger social welfare networks and greater gender equality have higher birth rates. Investments in health, education and skills need to be promoted and young people involved as change leaders.
The decline of the global population is, therefore, still a long way off and probably, when it occurs, it will happen gradually and this cannot be seen as a catastrophe for civilization. A new balance will come, but it will be different from the past. If we are to worry about ensuring a good standard of living for the global population, our top priority should be to avoid any risk that could wipe out all or a large part of humanity. It may be wiser to create a better world today than to worry about future fertility rates over which we have little control, concludes Coccia's article.
