At some point this month, the seven-and-a-half-billionth person alive on this planet will be born – if they haven’t been born already. No one knows quite when that will be, or where it will be, but it’s a milestone we can’t ignore.
It took until the time of Napoleon for the Earth to have a population of one billion. We reached two billion less than a century ago. Today, we add a billion every 12-15 years. The UN projects a likely population of 9.7bn by 2050, nearly 30 per cent more people than there are today – but it acknowledges 11bn a a genuine possibility. By 2100, a population of 11bn is likely, and 16bn possible.
Population growth is slowing – but not by enough. In many parts of the world, the “total fertility rate” (TFR, a way of reflecting birth rate) has fallen to below “replacement rate” of 2.1 children, at which births and deaths equal one another and population eventually stabilises. In most countries TFR is falling and has been doing so for many years. But a fall in the average rate is deceptive.
Today, the UN reports that global TFR is still above replacement rate, at 2.5, and in the least developed countries, a fertile woman will have four children on average. Niger has the world’s highest TFR – 7.5 children per woman.
In some countries, the decline in fertility rate has slowed to a stop, or has even reversed.
Population and poverty
Sub-Saharan Africa is not just driving global population growth: high birth rates are holding some African countries back from escaping terrible poverty, as communities and families struggle to meet the food, education and health needs of their growing numbers and national and local infrastructure cannot meet the demands of such high population growth. Locally, soils, water supplies and habitats for wildlife are all under pressure.
Lower fertility but more babies
Other factors drive our global population growth, including living longer. The most significant factor is the sheer number of us to have children: when there are more than a billion more people than a generation ago, fewer people being born per couple is outstripped by the growing number of couples and more people than ever before are being born.
More people, more impact
While numbers are growing quickest in the poorest countries, children born in the richest countries have the greatest impact on the environment. An American produces 160-times more CO2 than someone from Niger – a British person 70-times more.
Levels of consumption in the developed world demand more of the planet than it can provide. We are already using the resources of 1.6 planets – if we were all to live as Americans do, we would require four Earths to sustain us all.
Today, many more countries are escaping poverty but that welcome and necessary development poses a challenge for us all: as they become more affluent, their consumption and emissions increase. The rich world must cut its consumption – and the most effective way is to reduce numbers of consumers.
Every new human being makes sustaining a good life for all of us on a healthy planet more difficult to achieve. We have the power to reduce that impact and end population growth sooner.
If, on average, there is just half-a-child less per family in the future, there will be one billion fewer of us than the UN expects by 2050 – and four billion fewer by the end of the century (within the lifetimes of many children born today). Billions less mouths to feed, land to use and greenhouse gases to be produced.
Ensuring everyone has the opportunity and the right to choose their family size and that everyone who has that right exercises it thoughtfully and responsibly will mean a better future for the seven-and-a-half-billionth child and those born after them.