KUALA LUMPUR (March 28): In November 2022, the world crossed a milestone of eight billion people, but new analysis suggests the global population could peak just below nine billion people in 2050, then start falling. 

The new projection is significantly lower than several prominent population estimates, including those of the United Nations.

The researchers go further to say that if the world takes a “giant leap” in investment in economic development, education and health, then the global population could peak at 8.5 billion people by the middle of the century.

The new projections released on Monday (March 27) by researchers for the Earth4All initiative of the Global Challenges Foundation was published as a working paper titled People and Planet: 21st Century Sustainable Population Scenarios and Possible Living Standards Within Planetary Boundaries.

The team used a new system dynamics model, Earth4All, to explore two scenarios this century.

In the first scenario — too little, too late — the world continues to develop economically in a similar way to the last 50 years.

Many of the very poorest countries break free from extreme poverty. In this scenario, the researchers estimate that the global population could peak at 8.6 billion in 2050, before declining to seven billion in 2100.

In the second scenario, called the giant leap, researchers estimate that the population peaks at 8.5 billion people by around 2040, and declines to around six billion people by the end of the century.

This is achieved through unprecedented investment in poverty alleviation — particularly investment in education and health — along with extraordinary policy turnarounds on food and energy security, inequality and gender equity.

In this scenario, extreme poverty is eliminated in a generation (by 2060), with a marked impact on global population trends.

Per Espen Stoknes, the Earth4All project lead and a director of the Centre for Sustainability at Norwegian Business School, said rapid economic development in low-income countries would have a huge impact on fertility rates.

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

The team also analysed the connection between the population and exceeding planetary boundaries, which is linked to the carrying capacity of Earth.

Contrary to popular myths, the team found that the population size is not the prime driver of exceeding planetary boundaries, such as climate change.

Rather, it is extremely high material footprint levels among the world’s richest 10% that is destabilising the planet.