Earth’s population may peak at all-time high of about 9 billion in 2050s, research suggests

The global population could peak to an all-time high just below nine billion people in 2050 and then start falling, a new analysis suggests.

Researchers from the Earth4All initiative for the Global Challenges Foundation said if the world took a “giant leap” in investment in economic development, education and health, the global population could peak at 8.5 billion people by 2050.

The projection used a new model to explore two scenarios this century and the estimate is significantly lower than those by several predictions, including those of the United Nations.

In the first scenario, where the world is expected to continue to develop economically in a similar way to the last 50 years, researchers estimate the global population could peak at 8.6 in 2050 before declining to 7 billion in 2100.

In the second scenario – called the “Giant Leap” by researchers – they estimate that population could peak at 8.5 billion people by around 2040, and decline to around 6 billion people by the end of the century.

They say an unprecedented investment in poverty alleviation, especially in education and health as well as food and energy security, inequality and gender equity, could lead to this scenario.

Researchers say other prominent population projections tend to underplay the importance of rapid economic development.

“We know rapid economic development in low-income countries has a huge impact on fertility rates,” Per Espen Stoknes, one of the authors of the report, said.

“Fertility rates fall as girls get access to education and women are economically empowered and have access to better healthcare,” Dr Stoknes explained.

The analysis simulated interconnected factors such as population growth and economic development in 10 world regions such as sub-Saharan Africa, China and the United States.

Population growth is currently highest in some countries such as Angola, Niger, the Democratic Republic of Congo and Nigeria, and Afghanistan, experts said.

“If we assume these countries adopt successful policies for economic development then we can expect population to peak sooner rather than later,” Beniamino Callegari, co-author of the report, said.

Contrary to public popular myth, researchers also found that population size is not the prime driver of climate change.

Instead, they say it is the extremely high material footprint levels among the world’s richest 10 per cent that is destabilising the planet.

“Humanity’s main problem is luxury carbon and biosphere consumption, not population. 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,” Jorgen Randers, another co-author, said.

“A good life for all is only possible if the extreme resource use of the wealthy elite is reduced,” he concluded.