According to new UN data, the world’s population is projected to grow by more than 3 billion people by the end of the century, increasing from the current 7.7 bn to 10.9 bn. As in previous years, the data show that small changes in family size translate into a difference of several billion people by the end of the century – just half a child less per couple would see our population peak well before 2100 before declining to 7.3 bn.
The United Nations Department of Economic and Social Affairs (UNDESA) today released its latest World Population Prospects report which includes growth projections up to 2100. The revised figures are slightly lower than the ones released in the last report published in 2017. This is a welcome development as previous projections have usually been revised upwards.
The median or “medium variant” projection assumes global fertility will fall from just under 2.5 births per woman in 2019 to around 2.2 in 2050 and further to 1.9 in 2100.
Replacement rate: the average number of children needed per woman to achieve a stable population (no increase or decrease). The figure is slightly higher than 2 to account for infant and child mortality.
These figures represent the good, the bad and the ugly. The good: declining fertility and increasing longevity, reflecting improved quality of life for most of us, and at least the distant prospect of a flattening of population growth. The bad: astronomical population growth in the regions least able to cope, and the challenges of supporting a greater proportion of old people. And the ugly: billions more people putting intense pressure on a finite Earth, which already has overexploited natural resources, vanishing biodiversity and a dangerously warming climate. Our numbers and impact on the planet are already too great, and billions more people to consume, make greenhouse gases and pollute threaten to undo all the good we can do in terms of reducing our impact in other ways.
It’s very welcome to see a slight downwards adjustment in population projections but these figures nail the myth that population is going to decline soon – there’s only a one-in-four chance of that happening by the end of the century. Even these small gains are under threat. Family planning programmes in the world’s poorest countries are failing to meet their targets, while religious and political ideologues oppose birth control and choice over abortion, and promote pro-natal policies that threaten to undo the progress we’ve made.
We must end our addiction to unsustainable growth. Ageing populations are a challenge, but far from an insuperable one if we devote the resources necessary. Environmental catastrophe is a looming, credible and existential threat that requires us to take every ethical, practical measure at our disposal to ensure we have a habitable planet. If we don’t, nature could make its own intervention and our numbers could crash through the worst of all possible means.
These projections do offer hope: small changes in family size translate into a difference of several billion people by the end of the century – just half a child less per couple would see our population peak well before 2100 before declining to 7.3 bn. We have the time (just) and means to manage our population humanely and ethically such that future generations can live in balance and harmony with the natural world and the ecosystems upon which our wellbeing depends. That means family planning, education, women’s empowerment, ending poverty and promoting small families. Where people don’t have the choice to have a smaller family, they must have it – where they do have the choice, it’s vital they exercise it –especially in rich, high consuming countries where our environmental impact is so great. These projections represent too little progress, and without the right actions now, it will be too late to change them. That’s why the world needs an international policy framework on the overriding, upstream factor of population, as there is for the downstream issue of climate change.
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