New modelling suggests global population could peak at 8.6 billion midway through this century.
That’s a stark contrast to projections by the United Nations, which forecast a similar population figure for the end of this decade, and a peak of 10.4 billion by 2100.
The planet currently has more than eight billion people, having surpassed the milestone at the end of 2022.
The new prediction was released by the Global Challenges Foundation in Stockholm, and the estimates are predicated on assumed, rapid development in key global regions which implement successful economic policies, including successful investments health and education.
The model, dubbed Earth4All, considers two economic scenarios: one under current economic growth scenarios where the world’s poorest nations emerge from extreme poverty, resulting in a population peak of 8.8 billion by 2050, declining to 7.3 billion by century’s end.
The second, which assumes massive investments in poverty reduction, food and energy security, and gender equity, sees a peak of 8.5 billion by 2040, reducing to six billion by century’s end.
While the modelling assumes successful policy implementation, economic development and quality-of-life improvements at a national level tend to lead to higher education rates and healthcare access among women and girls. This drives down fertility rates.
While the authors note population is driven down by economic outcomes, a “big caveat” attached by the authors to their research emphasises the importance of “directed investment.”
“Governments in low-income countries must commit fully to pursuing economic development based on large investments in education, rather than economic growth driven solely by natural resources extraction,” they say.
Population not the problem
The Earth4All modelling shows two thirds of planetary sustainability boundaries including global warming, biodiversity loss, ozone depletion, air pollution and land use changes, are already breached .
Planetary boundaries are the limits within which humans can safely exist.
But population increase is not the primary driver behind these excesses, according to the authors, who instead find resource use by the world’s wealthiest 10% is the top pressure on planetary boundaries.
Among their proposals for a ‘Giant Leap’ in economic development driving population down are turnarounds in poverty, inequality, gender equality, food and energy systems.
These widescale changes include gender parity initiatives in health, education and employment, and a range of poverty reduction measures, such as a trillion-dollar green job fund for low-income countries, and debt cancellation. It also requires trillion-dollar investments in electrifying energy systems, and wealth taxes.
“Humanity’s main problem is luxury carbon and biosphere consumption, not population,” says Jorgen Randers, one of the Earth4All modellers.
“The places where population is rising fastest have extremely small environmental footprints per person compared with the places that reached peak population many decades ago.”