Too many people, too much consumption
By Paul R. Ehrlich and Anne H. Ehrlich
Yale Environment 360
Over some 60 million years, Homo sapiens has evolved into the dominant animal on the planet, acquiring binocular vision, upright posture, large brains, and — most importantly — language with syntax and that complex store of non-genetic information we call culture. However, in the last several centuries we’ve increasingly been using our relatively newly acquired power, especially our culturally evolved technologies, to deplete the natural capital of Earth — in particular its deep, rich agricultural soils, its groundwater stored during ice ages, and its biodiversity — as if there were no tomorrow.
The point, all too often ignored, is that this trend is being driven in large part by a combination of population growth and increasing per capita consumption, and it cannot be long continued without risking a collapse of our now-global civilization.
Too many people — and especially too many politicians and business executives — are under the delusion that such a disastrous end to the modern human enterprise can be avoided by technological fixes that will allow the population and the economy to grow forever. But if we fail to bring population growth and over-consumption under control — the number of people on Earth is expected to grow from 6.5 billion today to 9 billion by the second half of the 21st century — then we will inhabit a planet where life becomes increasingly untenable because of two looming crises: global heating, and the degradation of the natural systems on which we all depend.
Our species’ negative impact on our own life-support systems can be approximated by the equation:
I = P x A x T
In this equation, the size of the population (P) is multiplied by the average affluence or consumption per individual (A), and that in turn is multiplied by some measure of the technology (T) that services and drives the consumption.
Thus commuting in automobiles powered by subsidized fossil fuels on proliferating freeways creates a much greater T factor than commuting on bikes using simple paths or working at home on a computer network. The product of P, A, and T is Impact (I), a rough estimate of how much humanity is degrading the ecosystem services it depends upon.
The equation is not rocket science.
- Two billion people, all else being equal, put more greenhouse gases into the atmosphere than one billion people.
- Two billion rich people disrupt the climate more than two billion poor people.
- Three hundred million Americans consume more petroleum than 1.3 billion Chinese.
- And driving an SUV is using a far more environmentally malign transportation technology than riding mass transit.
The technological dimensions of our predicament — such as the need for alternatives to fossil fuel energy — are frequently discussed if too little acted upon. Judging from media reports and the statements of politicians, environmental problems, to the degree they are recognized, can be solved by minor changes in technologies and recycling (T).
Switching to ultra-light, fuel-efficient cars will obviously give some short-term advantage, but as population and consumption grow, they will pour still more carbon dioxide (and vaporized rubber) into the atmosphere and require more natural areas to be buried under concrete.
More recycling will help, but many of our society’s potentially most dangerous effluents (such as hormone-mimicking chemicals) cannot practically be recycled.
There is no technological change we can make that will permit growth in either human numbers or material affluence to continue to expand. In the face of this, the neglect of the intertwined issues of population and consumption is stunning.
Many past 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.
Each person added today to the population on average causes more damage to humanity’s critical life-support systems than did the previous addition — everything else being equal. The reason is simple: Homo sapiens became the dominant animal by being smart. Farmers didn’t settle first on poor soils where water was scarce, but rather in rich river valleys. That’s where most cities developed, where rich soils are now being paved over for roads and suburbs, and where water supplies are being polluted or overexploited.
As a result, to support additional people it is necessary to move to ever poorer lands, drill wells deeper, or tap increasingly remote sources to obtain water — and then spend more energy to transport that water ever greater distances to farm fields, homes, and factories.
Our distant ancestors could pick up nearly pure copper on Earth’s surface when they started to use metals; now people must use vast amounts of energy to mine and smelt gigantic amounts of copper ore of ever poorer quality, some in concentrations of less than one percent. The same can be said for other important metals.
And petroleum can no longer be found easily on or near the surface, but must be gleaned from wells drilled a mile or more deep, often in inaccessible localities, such as under continental shelves beneath the sea.
All of the paving, drilling, fertilizer manufacturing, pumping, smelting, and transporting needed to provide for the consumption of burgeoning numbers of people produces greenhouse gases and thus tightens the connection between population and climate disruption.
So why is the topic of overpopulation so generally ignored?
There are some obvious reasons.
Attempts by governments to limit their nation’s population growth are anathema to those on the right who believe the only role for governments in the bedroom is to force women to take unwanted babies to term.
Those on the left fear, with some legitimacy, that population control could turn racist or discriminatory in other ways — for example, attempting to reduce the numbers of minorities or the poor.
Many fear the specter of more of “them” compared to “us,” and all of us fear loss of liberty and economic decline (since population growth is often claimed necessary for economic health).
And there are religious leaders who still try to promote over-reproduction by their flocks, though in much of the world their efforts are largely futile (Catholic countries in Europe tend to be low-birthrate leaders, for example).
But much of the responsibility must go to ignorance, which leads mainstream media, even newspapers like The New York Times, to maintain a pro-natalist stance. For example, the Times had an article on June 29 about a “baby bust” in industrialized countries in which the United States (still growing) was noted as a “sparkling exception.” Beyond the media, great foundations have turned their “population programs” away from encouraging low fertility rates and toward topics like “changing sexual mores” — avoiding discussion of the contribution demographics is making to a possible collapse of civilization.
Some leading economists are starting to tackle the issue of over-consumption, but the problems and its cures are tough to analyze.
Silence on the over-consumption (Affluence) factor in the I = P x A x T equation is more readily explained.
Consumption is still viewed as an unalloyed good by many economists, along with business leaders and politicians, who tend to see jacking up consumption as a cure-all for economic ills. Too much unemployment? Encourage people to buy an SUV or a new refrigerator. Perpetual growth is the creed of the cancer cell, but third-rate economists can’t think of anything else. Some leading economists are starting to tackle the issue of over-consumption, but the problem and its cures are tough to analyze. Scientists have yet to develop consumption condoms or morning-after-shopping-spree pills.
And, of course, there are the vexing problems of consumption of people in poor countries. On one hand, a billion or more people have problems of under-consumption. Unless their basic needs are met, they are unlikely to be able to make important contributions to attaining sustainability. On the other hand, there is also the issue of the “new consumers” in developing economies such as China and India, where the wealth of a sizable minority is permitting them to acquire the consumption habits (e.g., eating a lot of meat and driving automobiles) of the rich nations. Consumption regulation is a lot more complex than population regulation, and it is much more difficult to find humane and equitable solutions to the problem.
The dominant animal is wasting its brilliance and its wonderful achievements; civilization’s fate is being determined by decision makers who determinedly look the other way in favor of immediate comfort and profit.
Thousands of scientists recently participated in a Millennium Ecosystem Assessment that outlined our current environmental dilemma, but the report’s dire message made very little impact.
Absent attention to that message, the fates of Easter Island, the Classic Maya civilization, and Nineveh — all of which collapsed following environmental degradation — await us all.
We believe it is possible to avoid that global denouement. Such mobilization means developing some consensus on goals — perhaps through a global dialogue in which people discuss the human predicament and decide whether they would like to see a maximum number of people living at a minimum standard of living, or perhaps a much lower population size that gives individuals a broad choice of lifestyles.
We have suggested a forum for such a dialogue, modeled partly on the Intergovernmental Panel on Climate Change, but with more “bottom up” participation. It is clear that only widespread changes in norms can give humanity a chance of attaining a sustainable and reasonably conflict-free society.
How to achieve such change — involving everything from demographic policies and transformation of planet-wide energy, industrial, and agricultural systems, to North-South and interfaith relationships and military postures — is a gigantic challenge to everyone. Politicians, industrialists, ecologists, social scientists, everyday citizens, and the media must join this debate. Whether it is possible remains to be seen; societies have managed to make major transitions in the recent past, as the civil rights revolution in the United States and the collapse of communism in the Soviet Union clearly demonstrate.
We’ll continue to hope and work for a cultural transformation in how we treat each other and the natural systems we depend upon. We can create a peaceful and sustainable global civilization, but it will require realistic thinking about the problems we face and a new mobilization of political will.
Source: Yale Environment 360
August 4, 2008
The most overpopulated nation
By Paul R. Ehrlich and Anne H. Ehrlich
Those of us who deal with population issues all the time are frequently confronted by people who believe the population problem belongs to someone else. But the view that overpopulation is not our problem just does not wash. Yes, poor nations have serious population problems, but in many respects rich nations have worse ones. Nothing recently has made the degree of over-population in the United States more obvious than George Bush’s confrontation with Iraq.
If the United States had stabilized its population in 1943, when it was in the process of winning the largest land war in history, today it would just have 135 million people. Assume that per capita energy consumption nevertheless had grown to today’s level; that is, our smaller population was still using sloppy technologies: gas-guzzling automobiles, inefficient light bulbs and pumps, poorly insulated buildings, and so on. Even if its citizens were just as profligate users of energy as we are, the 135 million Americans could satisfy their energy appetite without burning one drop of imported oil or one ounce of coal.1
The impact of a population on the environment can be roughly viewed as the product of three factors:
- the size of the population (P);
- the level of per capita consumption, or affluence (A);
- and the measure of the impact of the technology (T) used to supply each unit of consumption.
This provides the short hand equation:
I = P x A x T
which, although oversimplified (because the three factors P, A, and T are not independent), provides a basis for comparing the responsibility of different nations or groups for environmental deterioration.
Using the I = P x A x T, equation, one can see that the population problem in the United States is the most serious in the world.
First of all, the P factor is huge: With 255 million people, the United States is the third largest nation in the world.
And compared with other large nations, the A and T factors (which, when multiplied together yield per capita environmental impact) are also huge–their product being on the order of one-and-a-half times that of the Soviet Union; twice that of Britain, Sweden, France, or Australia; fourteen times that of China; forty times that of India; and almost three hundred times that of a Laotian or Ugandan. In per capita energy use, only Luxembourg, Canada, and a few oil-producing nations in the Middle East, such as Qatar and Bahrain, are in our league, and all those nations have comparatively tiny populations.
When the population multiplier is considered, the total impact of the United States becomes gigantic, several hundred times that of Bangladesh.
Few Laotians drive air-conditioned cars, read newspapers that transform large tracts of forest into overflowing landfills, fly in jet aircraft, eat fast-food hamburgers, or own refrigerators, several TVs, a VCR, or piles of plastic junk. But millions upon millions of Americans do. And in the process they burn roughly a quarter of the world’s fossil fuels, contributing carbon dioxide and many other undesirable combustion products to the atmosphere, and are major users of chlorofluorocarbons, chemicals that both add to the greenhouse effect and attack Earth’s vital ozone shield.
We have destroyed most of America’s forest cover (replacing a small fraction of it with biologically impoverished tree farms) and are busily trying to log the last of the old-growth forests in the Northwest, threatening the long-term prosperity of the timber industry, in part to service the junk bonds of rich easterners.
The western United States is one of the largest desertified areas on the planet due to overgrazing by cattle and sheep–not because we need the meat (only a small portion of our beef comes from the arid West) but because of the political power of ranchers in the western states and a nostalgic view of western history.
And Americans have contributed mightily to the destruction of tropical forests by purchasing products ranging from beef to tropical hardwoods derived from the forests.
Furthermore, each additional American adds disproportionately to the nation’s environmental impact. The metals used to support his or her life must be smelted from poorer ores at higher energy cost or transported from further away. The petroleum and water he or she consumes, on average, must come from more distant sources or from wells driven deeper. The wastes he or she produces must be carried further away, and so on. Activities that created little or no environmental burden when the United States had a small population, such as putting carbon dioxide into the atmosphere by burning fossil fuels, increase that burden with every additional individual when the population is large.
Consuming Our Capital
Basically, like most of the rest of the world, the United States has been consuming environmental capital–especially its deep, fertile soils, ice age ground-water, and biodiversity–and calling it growth. Furthermore, directly and by example, it has been helping other nations to do the same. It would not be remotely possible for Earth to support today’s 5.4 billion people on humanity’s “income” (which consists largely of solar energy) with present technologies and life-styles–even though for billions their life-style is living in misery, lacking an adequate diet, shelter, health care, education, and so on. And in the past decade the United States has retarded the worldwide movement towards population control because of the braindead policies of the Reagan and Bush administrations.
The U.S. Role
A large part of the responsibility for solving the human dilemma rests on the rich countries, and especially on the United States. We are the archetype of a gigantic, overpopulated, over-consuming rich nation, one that many ill-informed decision makers in poor nations would like to emulate. Unless we demonstrate by example that we understand the horrible mistakes made on our way to overdevelopment and that we are intent on reversing them, there seems little hope for the persistence of civilization.
The first step, of course, is for the United States to adapt a population policy designed to halt population growth and begin a gradual population decline. Such steps can be taken without immediately targeting an eventual optimum population size, since that optimum is far below 255 million. With leadership at the top, say, a president who kept pointing out that patriotic Americans stopped at two children maximum, we could probably achieve NPG in the United States within a couple of decades.
Americans would also, of course, have to recognize that for every immigrant who arrives in the United States and is not balanced by an emigrant, a birth must be forgone. We can never have a sane immigration policy until we have a sane population policy. The ideal mix of births and immigrants is a difficult question that must be solved by public debate.
The immigration issue is extremely complex and ethically difficult, but it must be faced. Equally daunting, after a decision on levels of immigration has been made, will be monitoring the flow and enforcing the quotas. Badly needed now is a wide-ranging discussion, first, of population policy and then of immigration within the context of that policy.
Optimum U.S. Population
Which brings us finally to the question of an optimum population for the United States. What can be said about it in light of the foregoing discussion? About the only thing that is certain is that the optimum will depend upon the scale of the A and T factors. And with a quality of life that more or less resembles today’s or is superior to it, and with present or foreseeable technologies, the optimum would be far below the present population.
Standard of living. Calculating an optimum size for any human population today is no easy task. First of all, the optimum size will depend on the standard of living of the average individual. A population of vegetarian Gandhis can be much larger than the one made up of super-consuming Trumps.
Environmental impacts of the technologies used. It also depends on the environmental impacts of the technologies used to support the life-style. An optimum population that uses light, highly fuel-efficient vehicles for personal transportation can be larger that one that drives gas-guzzlers. And one that uses commuter trains, buses, carpool vans, or even redesigns its cities to eliminate most commuting can be even bigger.
Life-styles of other nations. On the interdependent globe, the optimum size depends as well on the population sizes, technologies, and life-styles adopted by other nations.
Duration. Of course, optimum population size depends upon the answer to the question: “How long will it be sustained?” With a Reaganesque program of consuming all natural resources for the exclusive benefit of people now alive, the optimum will certainly be much higher than one that gives importance to the long-term maintenance of society.
Aggregate of life-style choices of individual citizens. Finally, the optimum population depends upon the aggregate of life-style choices of individual citizens. A United States in which nearly every family wanted to live on at least a five-acre parcel of land would have a much lower optimum population size than one populated with people who loved crowded living in action-filled cities.
Our personal preference would be to design a nation with a maximum of life-style options. If forced to make an estimate of the optimum population size of the United States, we would guess around seventy-five million people. That was about the population at the turn of the century, a time when the United States had enough wilderness and open space that people who wanted it could still find real solitude. With about that number, we believe, a permanently sustainable nation with a high quality of life could be designed–if it were embedded in a world that was similarly designed.
The critical point, though, is that views of an optimum are going to change as society and technology change and as we learn more about the environmental constraints within which society must operate. It is fun to make guesses now, but those guesses may be far from the consensus view of our society a century hence (when, for example, the concept of solitude may be well-nigh forgotten).
Unless there is a disaster, it will probably take a century or more even to approach an optimum–plenty of time for research and discussion. It suffices today to say that for our huge, overpopulated, super-consuming, technologically sloppy nation, the optimum was passed long ago. And because of decades of destruction of natural capital, the optimum will surely be lower the second time we approach it, and lower still for every year we postpone the turnaround. For our own sakes, and that of humanity as a whole, a rapid move to NGP is essential.
1. Technically the economic system would not have worked quite that way since demand varied, but the point is valid.
November 16, 1992