For decades, population hogged the spotlight, even when the glare was harsh. But all eyes are on climate change these days, though it appears that population concerns are rising anew, along with the atmosphere’s concentration of greenhouse gases.

Once upon a time, before global warming had become, as Jon Foley puts it, “the mother of all environmental problems,” (and he didn’t mean that in a good way), overpopulation was a pre-eminent concern of many green-minded scientists and activists. A famous book in the late 1960s gave rise to our greatest nightmare.

By the 1980s and 1990s, however, the politics of population turned ugly and environmental organizations began to back away from their campaigns. Some religious groups, pointing to the coercive measures adopted by China, attacked the “population stabilization” cause, and anti-immigrant elements in the United States co-opted it. As recently as the mid-2000s the issue had badly splintered the Sierra Club.


Since then, new fronts on the debate have opened up, with British science writer Fred Pearce asserting that concerns about overpopulation pale in comparison to challenges posed by overconsumption.

But Alex Renton, a journalist who specializes in development issues, makes another argument now being heard more often: It’s precisely because of our carbon intensive lifestyles that “population stabilization should be intrinsic to any climate change strategy.”

This line of reasoning was buttressed in a new paper published last year in the Proceedings of the National Academy of Sciences, PNAS. The authors of that study found that “slowing population growth could provide 16-29% of the emissions reductions suggested to be necessary by 2050 to avoid dangerous climate change.”

So where does all this leave us now, as experts tell us the world reaches the seven billion mark next week? Assuming climate change remains the “mother of all environmental problems” for the foreseeable future, then that framework will likely drive the debate over population.

Keith Kloor

Keith Kloor is a New York City-based freelance journalist who writes often about the environment and climate change.