Angst about declining global fertility and population is palpable and building. While certain high-fertility hotspots in developing countries will help to fuel a surge in the global population for many decades to come—reaching an estimated 10.4 billion people by 2100—humanity is at an inflection point where population decline is a lived experience and possibly irreversible in many parts of the world.
Deaths outpace births in many countries including China, as the cohort of retirees grows. With immigration slowed during the pandemic, Europe is now depopulating. Japan’s fertility rate has been so low for so long that one government official recently quipped, “If we go on like this, the country will disappear.” South Korea’s fertility rate (0.78 percent) is the lowest in the world, as women’s attitudes there turn sharply against marriage and childbirth.
Today’s drop in fertility rates was predictable and predicted for decades. The worst thing about its arrival now is that it’s so late in coming.
If governments had accepted shrinking demographics decades ago and adopted policies to encourage smaller families instead of fighting it by trying to prop up fertility rates, not only would the global population be lower today, there would be less greenhouse gas in the atmosphere, so the climate crisis would be less dire.
Those are the findings of a new white paper by IAMECON, an economic and social science research think tank based in Austin, Texas. The researchers computed global carbon savings that would have resulted had the world’s nations implemented family planning strategies recommended at world population conferences, such as the International Conference on Population and Development, which was held in Cairo in 1994. The paper also studied hypothetical scenarios to estimate how non-coercive strategies that empower women and girls could have lowered fertility more rapidly worldwide, and how this would have affected greenhouse gas emissions.
The question isn’t just theoretical or academic. In a concrete way, the future of humanity and millions of other species hinges on understanding the impact of human population and consumption on our climate, planet, and civilization. Literally everything we know and love is at stake.
Many are concerned about falling fertility rates undercutting economic growth. This is a fatally blinkered view, focusing on the size of the pie regardless of the fact that most people’s slice of that pie gets smaller. Moreover, it misses the larger impacts of overall population growth. Humanity has already overshot Earth’s carrying capacities.
We must reduce human demands for energy and resources to avoid the worst impacts of climate change. Population decline allows us to do that with less belt-tightening—and more recovery of wild nature.
The global population still increases by between 81 to 85 million annually, a pace undiminished for 50 years (although it is a smaller percentage change on a much bigger total population). It requires housing, employing, and servicing the equivalent of a whole new Germany, four Sao Paulos, two Tokyos, or ten New York Cities every year, drawing on resources that are already over allocated.
Anyone with siblings intuitively knows that children in larger families must compete for more limited resources. As populations continue to rise, so does inequality. Women’s and children’s rights decline, and children increasingly consume the resources that future children will need. The United Nations never explicitly made this connection between family planning policy and women’s and children’s rights, but if they had, it would have resulted in lower total fertility rates, the paper found.
The other critical connection to make is between population growth and GHG emissions. The two have a direct relationship, so lowering fertility rates would have also lowered global emissions. According to the IAMECON paper, if strategies to lower fertility rates were more widely implemented 50 years ago, it would have made a significant difference to the climate today. Today’s children would face less risk and a more positive, more equitable future.
It’s not too late to learn from these past mistakes. We could have taken a different and more intentional arc of growth—and still could. For decades it was taboo to talk about the impact of population growth on the climate and planet, but that’s finally starting to change. More and more people are realizing we have no choice. Women worldwide are increasingly speaking out about their parenting, career, and lifestyle choices, grappling with how they affect future generations and the Earth.
Those conversations need to reverberate around the world and reach the highest levels of government. Governments worldwide must adjust outdated thinking about growth for growth’s sake and gear policy toward lower fertility rates and a sustainable population.
One clear method for bending the arc of growth would be to take the extreme wealth at the top of the economic pyramid, the wealth that was made by externalizing costs on women and children in the form of unsustainable growth and an absence of guaranteed birth and development conditions for children, and using it to entitle and incentivize family reforms. This is a compelling approach because it is effective, but also because it is mandated by human rights. Crucially it can be done with laser-like specificity, geared for each context in which the payments are applied.
The opportunity now is to shift norms and make it socially and culturally acceptable to have small families—or even no children at all. We can increase support for family planning at the local, national, and international levels. We can remove restrictions on birth control—including vasectomies and early-to-mid-stage abortions. And we can restructure our economies so that they don’t depend on the myth of perpetual growth to avoid collapse.
On a planet with finite resources, progress on any environmental or social problem will be ephemeral at best until we curb our numbers, our consumption-based behaviors, and our pollution-generating activities. We can’t drain the atmospheric bathtub of greenhouse gases with the faucets on full blast. But by confronting the clear relationship between fertility rates and climate change, and adjusting our policies accordingly, we can at least turn the taps off.