World's population projected to hit eight billion today

The world's population is projected to hit an estimated 8 billion on Tuesday, November 15, according to a United Nations (UN) projection.

Much of the growth predicted between now and 2050 is expected to come from just eight countries.

It is an upward trend the UN warns will leave people in developing countries even further behind.

But experts say consumption is the biggest threat to the environment - which is highest in developed countries that are not undergoing big population increases.

Which countries' populations are growing fastest?

Of the eight countries expected to undergo the biggest population growth over the coming decades, half are in sub-Saharan Africa, including: Nigeria, Congo, Ethiopia and Tanzania. 

The UN says populations in the region are growing at 2.5% - more than three times the global average.

Nigeria is among eight countries the UN says will account for more than half the world's population growth between now and 2050.

“The population in many countries in sub-Saharan Africa is projected to double between 2022 and 2050, putting additional pressure on already strained resources and challenging policies aimed to reduce poverty and inequalities,” the UN report said.

It projected the world's population will reach around 8.5 billion in 2030, 9.7 billion in 2050 and 10.4 billion in 2100.

The other four countries with the fastest growing populations are: Egypt, Pakistan, the Philippines and India - which is set to overtake China as the world's most populous nation next year.

The UN's Day of 8 Billion milestone on Tuesday is more symbolic than precise, officials are careful to note, in a wide-ranging report released over the summer that makes some staggering projections.

The upward trend threatens to leave even more people in developing countries further behind, the report said, as governments struggle to provide enough classrooms and jobs for a rapidly growing number of youth, and food insecurity becomes an even more urgent problem.

Over the next three decades, Nigeria's population is expected to soar even more: from 216 million this year to 375 million, the UN says.

That will make the West African nation the fourth-most populous country in the world after India, China and the United States.

More than 15 million people in its capital, Lagos, compete for everything from electricity to light their homes to spots on crowded buses, often for two-hour commutes each way. Some Nigerian children set off for school as early as 5am.

“We are already over-stretching what we have — the housing, roads, the hospitals, schools. Everything is over-stretched," Gyang Dalyop, an urban planning and development consultant in Nigeria, said.

According to the UN, the population in sub-Saharan Africa is growing at 2.5% per year - more than three times the global average.

Some of that can be attributed to people living longer, but family size remains the driving factor. Women in sub-Saharan Africa on average have 4.6 births, twice the current global average of 2.3.

Families become larger when women start having children early, and four out of ten girls in Africa marry before they turn 18, according to UN figures.

The rate of teen pregnancy on the continent is the highest in the world - about half of the children born last year to mothers under 20 worldwide were in sub-Saharan Africa.

Still, any effort to reduce family size now would come too late to significantly slow the 2050 growth projections, the UN said. About two-thirds of it “will be driven by the momentum of past growth."

“Such growth would occur even if childbearing in today’s high-fertility countries were to fall immediately to around two births per woman,” the report found.

There are also important cultural reasons for large families. In sub-Saharan Africa, children are seen as a blessing and as a source of support for their elders, offering a greater chance of security in retirement.

Politics also played a role in Tanzania, where former President John Magufuli, who ruled the East African country from 2015 until his death in 2021, discouraged birth control, saying that a large population was good for the economy.

He opposed family planning programmes promoted by outside groups, and in a 2019 speech urged women not to “block ovaries.”

He even described users of contraceptives as “lazy” in a country he said was awash with cheap food. Under Magufuli, pregnant schoolgirls were even banned from returning to classrooms.

But his successor, Samia Suluhu Hassan, appeared to reverse government policy in comments last month when she said birth control was necessary in order not to overwhelm the country’s public infrastructure.

Warning developed nations' consumption driving climate threat

Rapid population growth also means more people vying for scarce water resources and leaves more families facing hunger as climate change increasingly impacts crop production in many parts of the world.

“There is also a greater pressure on the environment, increasing the challenges to food security that is also compounded by climate change,” Dr Srinath Reddy, president of the Public Health Foundation of India, said.

“Reducing inequality while focusing on adapting and mitigating climate change should be where our policy makers’ focus should be."

But experts say the rate of consumption, which is highest in developed countries not undergoing big population increases, is the biggest threat to the climate.

“Global evidence shows that a small portion of the world’s people use most of the Earth’s resources and produce most of its greenhouse gas emissions,” Poonam Muttreja, executive director of the Population Foundation of India, said.

"Over the past 25 years, the richest 10% of the global population has been responsible for more than half of all carbon emissions.”

Where is the world's population declining?

Even as populations soar in some countries, the UN says rates are expected to drop by 1% or more in 61 nations.

The populations of Australia and New Zealand, Northern Africa and Western Asia, and Oceania are expected to experience slower, but still upward growth through theend of the century.

However the populations of Eastern and South-Eastern Asia, Central and Southern Asia, Latin America and the Caribbean, and Europe and Northern America are projected to reach their peak size and to begin to decline before 2100.

In some countries in Europe and Northern America, progress in life expectancy was already slowing or stalling even before the outbreak of the Covid pandemic, the UN's report says. In the United Kingdom, Canada, and the US, vital statistics point to levels of life expectancy for recent years that are lower than what was previously projected.

The US population is now around 333 million, according to US Census Bureau data. The population growth rate in 2021 was just 0.1%, the lowest since the country was founded.

“Going forward, we’re going to have slower growth — the question is, how slow?” William Frey, a demographer at the Brookings Institution, said. “The real wild card for the U.S. and many other developed countries is immigration."

Charles Kenny, a senior fellow at the Center for Global Development in Washington, said environmental concerns surrounding the 8 billion mark should focus on consumption, particularly in developed countries.

"Population is not the problem, the way we consume is the problem - let’s change our consumption patterns."

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