A new study predicts population will drop sharply as developing economies grow.
You won’t hear this from the professional climate alarmists, but an important study on global demographics has good news for the future of greenhouse emissions. For some time, demographers have been scaling back forecasts of future population growth, but they may not have gone far enough. A new University of Washington studypublished in the Lancet argues that conventional population statistics don’t account for ongoing and projected future improvements in health care and education for women around the world. More literacy and better access to information about contraception are, along with urbanization, associated with declining fertility rates as women gain better control of their reproductive lives.
Looking at the impact of these forces, the study predicts some startling changes over the course of the century. Instead of the global population reaching between 9.4 billion and 12.7 billion by 2100 (as estimated in the 2019 United Nations World Population Prospects report), the new study suggests it will peak at 9.7 billion in 2064 and then decrease to about 8.8 billion by 2100. If the U.N.’s Sustainable Development Goals for education and contraceptive use are met in full, the researchers estimate that population could be as low as 6.29 billion in 2100. That would be 33% lower than the lowest current U.N. projection, and around 1.5 billion fewer than the Earth’s population today.
Even under the less aggressive scenario, the consequences would be far-reaching. China, where the University of Washington study expects population to decline by 48% to 732 million, would fall to third place, behind India and Nigeria, in the world population ranking. Population in 23 countries and territories, including Japan, South Korea, Italy, Portugal and Spain, would fall by 50% or more from their peaks. America, where continuing immigration is expected to offset declining fertility, would slip from third to fourth place with 336 million, barely more than today.
These shifts would lead to wrenching change. Health-care and pension systems would come under great stress around the world as shrinking numbers of working people support large populations of older people. But the impact on greenhouse emissions would be much more benign.
These projections may not pan out; 80 years is a long time horizon and predicting the reproductive choices of people not yet born is less science than art. Nevertheless, the study points to a vital linkage between climate and progress that the green movement often overlooks. Growth can be good. Economic development brings better health care and more information to women around the world.
There are several lessons here for policy makers wrestling with the difficult issues surrounding climate change. The first is that conventional strategies for combating climate change are too narrowly conceived. A focused global effort to ensure that the education and contraceptive SDG targets are fully met could have a significantly greater long-term impact on emissions than more-expensive and unpopular policy choices like carbon taxes or the mandated use of expensive renewables.
Reproduction isn’t the only human behavior that changes with greater wealth and more education. Societies that are wealthy enough to provide education and health care also act to preserve and restore their natural surroundings. Developing countries may hack down their forests, pollute their rivers, and foul their air, but when they become rich they invest in repairing the damage and reducing their footprint.