Is Population a Problem?

Catalyst / by Maywa Montenegro /

Will 9 billion people max out the Earth's natural resources? Or is overconsumption the real planetary threat? Three experts discuss the Gordian knot of wealth, fertility, and environmental impact — and why making do with less stuff matters so much.

The Catalyst: Driving Reactions to Issues in the News

Is Population or Consumption the Overriding Concern?
Our Panel Responds:

The number of people on Earth is expected to grow from 6.5 billion to about 9 billion by 2050. That much is relatively uncontroversial. But recently, we’ve seen disparate views emerge as to how this population growth will affect the planet.

Four decades after publishing The Population Bomb, Paul Ehrlich, for one, is still a firm believer that overpopulation—and along with it, overconsumption—is the central environmental crisis facing the world. In an opinion piece for Yale e360, he and Anne Ehrlich write: “Many human societies have collapsed under the weight of overpopulation and environmental neglect, but today the civilization in peril is global. The population factor in what appears to be a looming catastrophe is even greater than most people suppose.” The reason, say the Ehrlichs, is that each additional person today on average causes more damage to humanity’s life support systems than did the previous addition. And because Homo sapiens are smart creatures, we have already farmed the richest soils and tapped the most abundant water sources. Therefore, to support more people, it will be necessary to move to poorer lands, dig deeper wells, and spend more energy to transport food and water to increasingly distant homes and factories. Population, the Ehrlichs aver, remains an underacknowledged apocalypse in waiting.

Others, however, take a markedly different view. In the recently published book, The Coming Population Crash, and in a series of articles also for e360, environmental journalist Fred Pearce looks at the same demographic trends and sees very good news. “The population bomb is being defused at a quite remarkable rate,” he writes. “Women around the world have confounded the doomsters and are choosing to have dramatically fewer babies.” He then goes on to cite declining fertility rates in countries across Europe, Asia, and Latin America. And in Africa, where high fertility remains the norm, Pearce is optimistic that those extra people can provide a way out of the continent’s poverty trap. Bad agriculture, not population growth, he contends, is the continent’s main predicament—and in this essay, he describes how more people, employed on ecologically friendly, small-scale farms will be key to African sustainable development. Chris Reij, a Dutch geographer whom Pearce interviews for the article, concurs. “The idea that population pressure inevitably leads to increased land-degradation is a myth,” he says. “It does not. Innovation is common in regions where there is high population pressure.”

Consumption, not population, Pearce concludes, is the main problem confronting human society today. After all, he writes, “virtually all of the extra 2 billion or so people expected on this planet in the coming 40 years will be in the poor half of the world.” Assuming per capita emissions remain roughly where they are today, those 2 billion poor people will only boost the developing world’s share of greenhouse gas emissions from 7 to 11 percent. In other words, achieving zero population growth—even if it were possible—would barely touch the climate problem. The real culprits, according to Pearce, are not “generations of poor not yet born” people, but the stable population in the developed world with its gigantic ecological footprint.

The Erhlichs, of course, also cite consumption as a critical concern. But in their view, consumption and population (according to the familiar equation I=PAT, with “P” being population and “A” representing consumption) are mutually reinforcing parameters. For Pearce, population has been dangerously overhyped—and in the worst cases, by those seeking to excuse overconsumers and blame the poor for our common environmental predicament. The Ehrlichs look at demographic trends to 2050 and see twin synergistic forces: too many people and too much consumption. Pearce examines the same trends and sees a silver lining in that the rate of growth is trailing off, even if the numbers are still rising. And where those numbers are growing is crucial too because in places like Africa, he believes, human ingenuity and human labor can become a part of a food-producing environmental solution.

Against the backdrop of these two contrasting views, we’d like to ask you: What is your assessment of the severity of “the population problem”? Will more and wealthier people on the planet strain our already taxed ecosystems, as the Ehrlichs argue, or as Pearce believes, will our newcomers have negligible environmental impact? Is population or consumption the overriding concern—is it possible to meaningfully distinguish the two?

The fastest way to slow our population growth is to reduce poverty, yet the fastest way to run out of resources is to increase wealth.

Julia Whitty is the Environmental Correspondent for Mother Jones. Her latest book DEEP BLUE HOME: An Intimate Ecology of Our Wild Ocean will be published in July.

For my cover article in the current Mother Jones (The Last Taboo), I attempted to address just the question posed here: Are our population problems a result of too few condoms or too many credit cards? I chose to base my article out of Kolkata (formerly Calcutta), India, a place associated in the minds of many with all the ills of an overcrowded world, and also home to my maternal lineage.

Kolkata’s an interesting place to try and peer into our collective future. Seen from above, the circulatory system of roads and railroads of the entire Indian east—home to 300 million people, roughly the same as the US—funnel into the city. Trucks and freight trains run day and night, laden with fuel, fish, and food. The city itself funnels into a central core, a defensible bend in the Hooghly River and the classic star-shaped, 18th-century Fort William—a stronghold harking back to a time when wealth was measured in tea, silk, jute, ivory, and gemstones, and when survival was defended by cannon fire.

Survival in the 21st century is different. The real measure of it lies in the depth of the snowpack in the Himalayas, in the sustainable tonnage of fish caught in the Bay of Bengal, in the inches of topsoil left on the fertile Indian plains, and in the parts per million of coal-smoke in the air. The root cause of India’s dwindling resources and escalating pollution is the same: the continued exponential growth of humankind.

As recently as 1965, when the world population stood at 3.3 billion, we collectively taxed only 70 percent of Earth’s biocapacity each year—using only seven-tenths of the planet’s lands, waters, and air to produce what we consumed and to absorb our greenhouse gas emissions. According to the California think tank the Global Footprint Network, we first overdrew our accounts in 1983, when our population of 4.7 billion began to consume natural resources faster than they could be replenished, a phenomenon called ecological overshoot. Last year, 6.8 billion of us consumed the equivalent of 1.4 Earths.

The only known solution to our ecological overshoot is to decelerate our population growth faster than it’s decelerating now and eventually reverse it—at the same time we slow and eventually reverse consumption levels. Success in these twin facets of human sustainability will crack the unbreakable code of our most pressing global issues: climate change, food scarcity, water supplies, immigration, health care, biodiversity loss, even war. On one front we’ve already made unprecedented strides: reducing global fertility from 4.9 in 1950 to 2.5 today—an accomplishment of trial and sometimes brutally coercive error, but also a result of one woman at a time making her individual choices. The speed of this childbearing revolution, swimming hard against the tide of our essential biological programming, rates as perhaps our greatest collective feat to date.

The paradox embedded in our future is that the fastest way to slow our population growth is to reduce poverty, yet the fastest way to run out of resources is to increase wealth. The trial ahead is to strike the delicate compromise: between fewer people, and more people with fewer needs, in a new economy geared towards sustainability. The easy part is birth control. The hard part, as Paul and Anne Ehrlich write, is that we still don’t have condoms to prevent overconsumption, or morning-after pills to reverse unwanted buying-sprees. Perhaps we need delegations of kindly people from the developing world to come to our shores and remind us how to live simply again.

Cartogram by

POPULATION distribution across the planet, as of 2002.

In the United States alone, we burn roughly 25 percent of the world fossil fuels — about 6 times our share of the planetary pie.

Jonathan Foley is the director of the Institute on the Environment at the University of the Minnesota, where he is also a professor and McKnight Presidential Chair of Global Ecology and Sustainability. He also leads the institute’s Global Landscapes Initiative, which focuses on the nexus of global land use, agriculture, food security                                       and environment.

I can’t seem to give a public presentation on environmental issues without someone in the audience standing up and asking, “But isn’t the real problem overpopulation?”  Nine times out of ten, this person is white, older, of at least middle-class income, and well educated.  And, most of the time, these folks have several children of their own, and often many grandchildren.

At these moments, my irony detector is usually going off the scale.

But maybe they’re right? Isn’t population a huge problem? Surely the vast number of human beings now on the planet is an issue? Or are they looking for a convenient scapegoat, ignoring the possibility that our own patterns of consumption are the central issue instead?

Unfortunately, as with most important questions, there isn’t a simple, single answer.

To start, though, let’s be clear about one thing: global environmental problems are not solely caused by population growth.  The number of people on the planet per se, doesn’t affect our climate, our ecosystems or our natural resources. It’s how we collectively consume and pollute that impacts the environment.

Plus, a relatively small number of us are responsible for the vast majority of the globe’s consumption, pollution, land and water degradation, and biodiversity loss. In the United States alone, a country of 300 million, or about 4 percent of the global population, we burn roughly 25 percent of the world fossil fuels – or about 6 times our share of the planetary pie.

And, for the most part, the richest nations of the world are not growing their population (except through immigration). Instead, we are increasing our use of resources, with no end in sight, while desperately trying to keep our consumer-based economies afloat.

So, are things really that simple? Is the problem simply overconsumption by the rich, and not population?

No. Population growth is definitely contributing to our global problems too, but in a different way.

The world’s poorest nations, which include some of the fastest growing populations, are often the most vulnerable to environmental, political and economic disruptions, whether from storms, earthquakes, epidemics or sudden financial shocks. While these people are not contributing very much to global environmental degradation, so far, they are the going to be the first to feel the impacts – whether from famine, disease or dislocation.

This creates the compound tragedy of our times. In simple terms, rich people are rapidly increasing their consumption, and causing the lion’s share of our planetary environmental problems. But poor people are still growing in numbers, which sadly puts more people in harms way, and is increasing the magnitude of human vulnerability to environmental disruption.

It’s a one-two punch: the rich, big consumers of the world are consuming more and more (with no end in sight), causing a disproportionate share of the world’s environmental destruction, while the poorest and most vulnerable populations (who are going to be hit hardest by environmental collapse) are growing faster than anyone else.

Yes, population is an issue. And so is overconsumption.  But we have to recognize that they are working in parallel, at very different ends of the economic scale, creating the doubly whammy of environmental degradation (through increasing overconsumption) and increasing vulnerability (through population growth).

It’s a perfect storm of human suffering.

As if that weren’t enough, the world is adding a difficult twist: Sizable numbers of poor people are moving into the global middle class, dramatically increasing their levels of consumption along the way. While the world will continue to hang in the balance between growing numbers of poor and stable numbers of rapacious consumers, the number of megaconsumers will also slowly increase over time.  And we in the United States can hardly complain: none of us has the right to deny poorer nations the right to develop (especially when their per capita consumption is still so much lower than our own).

So, in all of this doom and gloom, is there any good news?

Yes: not too long ago, demographers were forecasting that global population by 2050 would reach 10 to 12 billion, instead of the 9 we expect today. And when I was a kid, people were talking about 15 to 18 billion people by 2050. As population forecasts have been revised over the years, they have generally been revised downward.

Fortunately, population growth in the world appears to be slowing faster than anyone forecasted, largely through voluntarily measures (with the exception of a few states like China), while simultaneously improving human welfare around the world. The demographic transition appears to be working. People, all across the world, are choosing to have smaller families.

The bad news is that consumption appears to be still increasing rapidly, with no end in sight. So far, there hasn’t been a negative feedback on consumption, telling us to slow down. The rich want to be richer. Big consumers want to consume even more. It’s an endless treadmill, and no one knows how to get off. Instead of the “Population Bomb” of the 1960s, we now have an even larger “Consumption Bomb”, and we don’t now how to diffuse it. And this bomb may well define our relationship to the environment for the 21 century and beyond.

Going back to the people in the audience, how should I answer their question about population being “the real problem” in the global environment?
I will continue to give them the best answer I have: Yes. And No.

Cartogram by

WEALTH distribution across the planet, in terms of GDP per person (2002).

Seven Sensible Statements on Population and Consumption

Joseph Chamie is research director at the Center for Migration Studies, a non-profit organization providing research and a forum for debate on international migration. Before arriving at CMS, Chamie was Director of the United Nations Population Division at the UN Secretariat in New York City.

I. The unprecedented growth of world population during the 20th century has greatly impacted all life forms and the entire natural environment on this planet.
The 20th century was one of revolutionary demographic developments, unparalleled during all preceding centuries.  World population nearly quadrupled during the past century, growing from 1.6 to 6.1 billion, greatly impacting all the world’s ecosystems. In the future, historians may well conclude that the most significant event of the 20th century was the rapid growth of world population.

II. Current rates of population growth are unsustainable over the long term.
While world population in the distant future remains uncertain, several things are clear today. First, if growth rates were to remain fixed at today’s levels, world population would nearly double around mid-century and leap to 40 billion by 2100. Second, although slowing down, the rapid growth of the world’s population is not yet over and will continue to stress the earth’s environment. In the near term, there is little doubt that the world’s population will reach 7 billion, probably by 2011, and will likely reach the 8 billion mark around 2025. 

III. Stabilizing world population would help enormously to tackle environmental problems.
The growth of world population is clearly an important aspect of environmental stress and degradation, as every man, woman and child requires water, food, clothing shelter and energy. Moving towards population stabilization, while not a panacea for the world’s problems, will make it far easier to address problems such as environmental degradation, climate change, shortages of water, food and critical natural resources as well as poverty and development and human rights abuses.

IV. The developed nations, a fraction of world population, are disproportionately responsible for many global environmental problems.
The rich industrialized countries, representing less than a fifth of world population, have greatly impacted the environment. For example, they are responsible for approximately four-fifths of carbon dioxide buildup, which has accumulated in the atmosphere over decades and centuries.  The imbalance is even more striking on a per capita basis. The CO2 contribution to the atmosphere of the average American is roughly 5 times that of the average Mexican and nearly 20 times as much as the average Indian. 

V. While raising the living standards of the growing populations in developing countries is a certainly a desirable goal, it will likely worsen the planet’s ecosystems.
Understandably, the growing populations of the developing countries hope to raise their living standards. However, even small improvements in their relatively low living standards will have negative environmental consequences. Moreover, continuing high rates of population growth, especially in Africa and Asia, will make matters even worse, exacerbating environmental degradation as well as retarding economic and social development.

VI. Overpopulation and overconsumption are both central to resolving the planet’s environmental problems.
Reducing rapid rates of population growth has a central role to play in safeguarding the earth’s environment.  There is hardly any environmental problem whose solution would be easier with a larger population.  In addition, sound environmentally sustainable technologies need to be developed now along side significant reductions and reversals in damaging patterns of production and consumption. 

VII. Global agreements on resolving population and environmental problems already exist and simply need to be implemented.
During the past two decades the international community of nations has adopted various recommendations relating to population and environment at United Nations conferences and summits. The following recommendation from the 1994 International Conference on Population and Development reflects the global consensus that now requires implementation:

“Recognizing that the ultimate goal is the improvement of the quality of life of present and future generations, the objective is to facilitate the demographic transition as soon as possible in countries where there is an imbalance between demographic rates and social, economic, and environmental goals, while fully respecting human rights. This process will contribute to the stabilization of the world population, and, together with changes in unsustainable patterns of production and consumption, to sustainable development and economic growth.”

Cartogram by

POVERTY distribution across the planet, as of 2002.


Originally published June 10, 2010

Tags agriculture climate development economics environment population poverty

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