Should we worry about eight billion people?

This story was originally published by High Country News and appears here as part of the Climate Desk collaboration.

This is an instalment of the Landline, a fortnightly newsletter from High Country News about land, water, wildlife, climate and conservation in the western United States.

Is overpopulation the environmental elephant in the room?

Last month, the United Nations announced that the Earth’s population had reached eight billion. The organization’s leaders don’t see all those humans as something to fear, but rather as, in the words of Secretary General António Guterres, “an occasion to celebrate diversity and advancements while considering humanity’s shared responsibility for the planet.”

But judging from the letters I get after almost every environment-related piece I write, I suspect that some readers would disagree.

“I am an avid ‘environmentalist,’” a reader recently wrote. “Simple, plain truth fact: Whether it is climate change, wildlife habitat, immigration, and yes, even gun violence. We will NEVER make much progress … until we make significant gains in stabilizing and ultimately reducing the cancer of human population growth.”

This note echoes hundreds of other responses I’ve received over the last couple decades. The basic idea is that all aspects of environmental degradation — along with traffic congestion and the housing crisis — are rooted in overpopulation. And, the argument goes, not mentioning this in environmental stories is irresponsible, verging on dishonest. “Population growth is the environmentalists’ ‘elephant in the room,’” another reader wrote. “We ignore the issue at our peril.”

We at Landline would like to use the eight-billion benchmark as an opportunity to stop ignoring population. But, fair warning: You might not like what we have to say.

No, I’m not going to tell you to stop worrying about population growth. Even as the UN celebrates the advances in medicine and nutrition that make it possible for billions of people to exist on Earth, it acknowledges the challenges presented by rapidly growing numbers in places like Nigeria. And no, I’m not going to deride every overpopulationist as a racist or eco-fascist or eugenicist. While it’s true that fear of overpopulation is often used to justify racism or eco-fascist views or xenophobia, there are plenty of folks who are genuinely concerned about the planet’s ability to sustain eight billion people, no matter where or who or what colour those people may be.

But I will suggest that you’re barking up the wrong tree.

Most folks would agree that the real worry here is not the sheer numbers, but their collective impact on the environment. We — the planet’s human inhabitants — are clearing land, levelling forests and mountains, mining and drilling minerals and burning fossil fuels in order to sustain ourselves and our lifestyles. That, in turn, is diminishing biodiversity, driving species to extinction and stretching the planet’s carrying capacity to a snapping point, thereby imperilling our own species’ survival. The problems are exacerbated as planet-warming greenhouse gas emissions soar, further diminishing freshwater stores and hurting food production.

And the environmental impacts, put simply, are the product of population multiplied by per capita consumption. It would stand to reason that with every added unit of humanity comes a corresponding and proportional increase in environmental impact. The thing is, per capita consumption varies widely across the globe and the demographic spectrum, vastly outweighing simple population numbers in our impact equation.

14
Per cent by which total global energy consumption has increased over the last decade.

11
Per cent by which total global population increased during that same period.

6
Per cent by which total global carbon emissions from energy use increased over the decade.

That is to say, the affluent consume far more than everyone else and therefore have a much greater environmental impact, throwing the aforementioned equation into disarray. The richest 10 per cent of the globe’s population are responsible for nearly half of all “lifestyle consumption emissions,” according to Oxfam, while the poorest half is responsible for just 10 per cent of those emissions. Another way to look at this is that each person at the top of the global wealth ladder emits about 31.25 metric tons of carbon dioxide-equivalent each year, while each of the globe’s poorest 50 per cent emits about 1.25 tons of CO2. That’s because folks in the so-called “developed” world burn through a heck of a lot more fossil fuels, food, water, minerals, Big Macs — you name it — than those in less-affluent, rapidly growing regions.

Increases in population still result in increases in overall environmental impact. But per capita consumption plays a far bigger role. It’s runaway consumption, not unhindered population growth, that is most responsible for the habitat loss, land-use changes and resource exploitation that most threaten biodiversity and cause the runaway greenhouse gas emissions that are altering the climate.

4.7 billion
Metric tons of carbon dioxide emitted from energy use in the United States in 2021.

3.8 billion
Metric tons of carbon dioxide emitted by Europe's energy use in 2021.

1.3 billion
Metric tons of carbon dioxide emitted by Africa from energy use in 2021.

This equation — combined with the disproportional influence of consumption over sheer population numbers — holds true even at a regional level.

Perhaps the most prominent example of a system in the West that has exceeded the carrying capacity is the Colorado River. The population has dramatically increased in the seven Colorado River Basin states over the last few decades. And, during that same time, demand for the river’s water has come to vastly exceed the supply.

At first glance, it would appear that a larger population has resulted in greater consumption, thereby draining the reservoirs. But the data doesn’t back this up. While Colorado River consumption climbed along with population for decades after the Colorado River Compact was signed a century ago, that demand levelled over the last couple of decades, even as the population exploded. Yes, consumptive use of the Colorado River’s waters held steady or even dropped as the population climbed, as counterintuitive as that may seem.

750,000
Amount by which the Las Vegas metro area population increased between 2002 and 2021.

26 billion gallons
Amount by which the Las Vegas metro area overall water use decreased during that same period.

500,000 acre-feet
Estimated amount of Colorado River water used to irrigate alfalfa fields in a single California irrigation district per year, or nearly twice the Las Vegas area’s total annual consumption.

Meanwhile, the West’s wealthiest guzzle more and more water and energy and resources with every new pile of cash (or cryptocurrency or stocks or yachts) they amass, from the Kardashians using hundreds of thousands of gallons of water per month to keep their Los Angeles-area estate verdant during the most severe drought in 1,200 years, to Drake burning through jet fuel to take a 14-minute trip in his custom 767, to an L.A. mansion with a $50,000 monthly electricity bill. Yes, $50k for electricity to keep the monstrosity’s 105,000 square feet, or 217 average-sized Hong Kong homes, cool during the increasingly hot California summers.

It’s not just the billionaires. Americans in general tend to favour relatively giant automobiles and lawns and houses — the average home size in Colorado Springs is almost 2,800 square feet. These, in turn, require more energy, wider roads, more water and lead to residential sprawl, which gobbles up farmland and open space and wildlife habitat. Bigger physical footprints almost always have bigger environmental footprints.

This isn’t the result of eight billion people on the planet or cross-border immigration. It’s the natural outcome of the dominant culture, which values affluence, economic growth and corporate profit above all else. It’s societal greed and an emptiness that always yearns for more, in part because corporate marketing schemes have convinced us that the more we accumulate, the happier we are. But Americans don’t have the highest quality of life, they just lead the most profligate lives, throwing away enough food each year, for example, to feed an entire nation.

161 to 335 billion tons
Estimated amount of food wasted in the U.S. supply chain each year, which amounts to as much as 1,032 pounds per person.

140 million
Acres of land required to grow food that is wasted each year in the U.S.

5.9 trillion
Gallons of water used to grow food that is wasted each year in the U.S.

Trying to control the population — whatever that might look like — isn’t going to solve those problems. Only a rejiggering of the system, a suppression of the collective capitalist appetite, a debunking of the belief that all growth is good and that more is more, will right the sinking ship we’re on.

As for the eight billion, most experts say the best way to stabilize the global population is to empower and educate women, increase access to birth control, ensure that women have reproductive freedom and tackle wealth inequality.

Meanwhile, policymakers and thinkers and environmentalists should focus more on reducing consumption and changing what is consumed, especially by the affluent. Because when it comes to the environment, that’s the real elephant weighing down the planet.