forum discussion #18

Defusing the Population Bomb

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Listen to our interview with environmental journalist Fred Pearce. He’s our guest in the latest Science Forum discussion.

There are almost 7 billion human beings on the planet today, and that number will likely rise to 9 billion by 2050. What will that mean for the earth’s environment?

Not much, according to Pearce.

Pearce rebuts fears about population growth in his new book, The Coming Population Crash: and Our Planet’s Surprising Future.
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Pearce says birth rates today are much lower than in the last century, and after a few decades, our numbers will likely fall and then stabilize. He documents how women from all over the world – rich and poor alike – are choosing to have fewer children.

Pearce also contends that population growth isn’t the root cause of today’s environmental ills. The current growth in population is occurring in poorer countries, which consume relatively little of the earth’s resources.

The biggest environmental threat, Pearce argues, is consumption in rich countries.

“We’re defusing the population bomb,” says Pearce. “But we haven’t begun to defuse the consumption bomb.”

Do you agree? Come share your thoughts with Pearce in this online discussion. The conversation is just to the right.

  • Which is easier to defuse – a population bomb, or a consumption bomb?
  • Would you be willing to limit the size of your family for the good of the earth?
  • What do you think is the “right” population for our planet? Seven billion people? Seven million?

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The guest has left this discussion, but feel free to leave your thoughts.

Your Comments

  1. Error: Unable to create directory /home/worldsci/public_html//wp-content/uploads/2014/04. Is its parent directory writable by the server? Fred Pearce

    Do we have to be so gloomy about growing world population? I don’t think so. A little-known fact is that women today are having half as many children worldwide as their mothers did. It looks like we may see “peak population” by mid-century, and likely a decline in numbers thereafter. This is great news. But it won’t save the planet, because while we are defusing the population bomb, the real damage to the environment is our soaring consumption. So to my mind, peak population won’t fix the world’s problems, but it does mean that we are not doomed by never-ending population growth.

    Does that make me a crazy optimist?

    I welcome your thoughts and comments.

    • What about the widely held view that population growth is a function of the discovery and exploitation of cheap, easy-to-get oil. Everything we consume is drenched in oil — especially our food. When oil production peaks (some say it already has) – gas, food and most everything else will be in short supply and outrageously expensive.

      Deep food shortages will bring down the population in a number of unpleasant ways. This is a problem of integration of the end of easy oill, climate instability and economic failures.

      It is interesting to me that the news media shy away from this topic. Could it be that even public radio is controlled by the oil companies?

      We could begin preparing by re-localizing everything? …but will we?

      • Error: Unable to create directory /home/worldsci/public_html//wp-content/uploads/2014/04. Is its parent directory writable by the server? Fred Pearce

        What you describe is the Malthusian version of the future. Technology doesn’t change; we face a resource crunch; and everything goes pear-shaped. It could happen. But it needn’t. It didn’t when Malthus first described it in the early 19th century. It didn’t when Ehrlich wrote his Population Bomb book in the 1960s — after which, amazingly, we doubled world food production ahead of the doubling of world population that has happened since. Right now — both because of possible peak oil and the near-certainty of climate change — we have to change how we make the energy that keeps our world turning, including our farming system. Technologically I( am an optimist. We know how to do that. Will we actually do it? That’s the big q, but luckily peak population will help.

    • You are certainly correct that one of the most important factors is human consumption of much more than is needed. But with unlimited population growth–even with curtailment of individual consumption; many, many species will have nowhere to live. Many species are already “on the brink” as I’m sure you are aware. Don’t you think it is important that we have a rich diversity of beings and ecosystems? Even a stable system of people and the plants and animals that help them would not be acceptable to me. Nor to most other people who are aware of the richness and diversity of the world.

      • Error: Unable to create directory /home/worldsci/public_html//wp-content/uploads/2014/04. Is its parent directory writable by the server? Fred Pearce

        Carol, Yes biodiversity is vital. Not just for its intrinsic value but for the stability of “Earth systems” — keeping the planet habitable. I guess at root i am a humanist, so i don’t see people as pollution. But we have to find an accommodation with the rest of the planet.
        I disagree with your assumption that we face “unlimited population growth”. Not quite sure what you mean by unlimited. But as I keep saying, the surge in numbers that has been going on at a fast rate for more than a century across the world seems to be coming to an end. It is no longer the main driver of the destruction of nature. So while of course, we have done a huge amount of damage, the solutions now lie in curbing consumption patterns.

    • Steve Bismarck

      The assertion that consumption ethics could trump reproductive responsibility passes neither the initial sniff test nor arithmetic validation. Let’s construct a little population paradigm. The Brown family is not environmentally conscious in their lifestyle at all. For strictly economic reasons, though, they believe in having only one child. The Green family is VERY abstemious in their consumption footprint, but enjoy children and have three kids.
      We catch up with them late in life as their great-grandchildren are maturing. The familial culture of both consumption and procreation has been faithfully maintained at each generation. Which extended family casts the smaller ecological footprint: the 5-member, high-impact Brown family or the 41-members of the low-consumption Green family?

      • Error: Unable to create directory /home/worldsci/public_html//wp-content/uploads/2014/04. Is its parent directory writable by the server? Fred Pearce

        True up to a point. But if the Brown family is in the rich world and the Green family is in, say, Ethiopia, then the 41-member Green family would still have a much smaller footprint than the five-member Brown family. And it is in countries like Ethiopia where populations are still rising. Moreover, after a couple of generations we have every reason to believe that families will be much smaller in Ethiopia, too. (Already the people of the capital Addis have only around two children.)

      • Steve Bismarck

        I think it’s clear that we’re comparing two families in the same culture. Trying to restructure the paradigm by relocating one family to Africa is a textbook example of the Red Herring argument. Look, the point is that reducing consumption, while certainly a noble goal, is woefully inefficient in mathematical terms when compared to reproductive restraint. The amount of resource privation a family would need to countenance in order to offset even a single child’s footprint is staggering.

        The most important thing to understand is that REPRODUCTION CREATES NEW CONSUMERS and is therefore a multiplicative form of consumption itself.

        You’re proposing the construct of “peak population” as an analogue to peak oil, I guess, but the notion has a number of flaws and I don’t find it a useful metaphor. Be they waxing or waning, unsustainable population sizes are just what that term implies. How much damage will we do to the rest of the biosphere in riding out our population trajectory?

        Fertility alone is not a useful metric in evaluating population trends. The birth-death ratio (currently about 2.45:1) is what matters. The kind of cultural enlightenment that lowers natality also tends to promote higher individual longevity, so the initial reduction in family size is easily washed out by generational overlap. This is not a time to be blythe about population increase. Let’s give Mother Earth’s exhausted womb a rest.

    • Matt Stori

      As regions on this planet with insufficient resources demonstrate, the population issue is built into human nature, aka as civil strife.
      With sufficient stress, even “mature” continents eventually will fall into that scenario, as suggests the resurgence of extreme right parties…

  2. I spent a month blogging about this a couple months back (see link above), so I think I’m reasonably well-informed. I agree, the problem isn’t population so much as consumption. But “defusing” either bomb is rife with difficulty. Yet try we must.

    • Error: Unable to create directory /home/worldsci/public_html//wp-content/uploads/2014/04. Is its parent directory writable by the server? Fred Pearce

      I agree about consumption, but i think the world’s women are right on the button with defusing the population bomb. Half the world now lives in countries where fertility rates are at or below the replacement level (which, globally averaged, is 2.3 children per woman, allowing for girls who don’t make it to adulthood). And most of the rest will likely join them soon. The really good news is that this isn’t a result of compulsion or heavy-duty population policies, but of women (and men, too) making real choices about how they want to live their lives. Women now know they only need to have 2 or 3 children to secure the next generation, and they are taking the chance to do that and find other things to do with their lives. Like — we can hope — fixing our energy problems

      • I agree — I was referring to efforts to control population such as China’s “one child” policy, which has horrendous problems and arguably didn’t really work at all.

  3. Fred,
    Thank you for your reply. I am neither ann optimist nor a pessimist; and no, I am not a realist, whatever that is.
    I agree that consumption is a symptom. But without the over abundant, seemingly endless supply of ancient sunlight energy we cannot produce the amounts of food we do today, let alone for an additional 2 billion.
    And to develop technology to solve a problem that will begin hitting us within ten years, some say much sooner, is a tough order to fill. We don’t have any idea how to do this and by best estimates it will take 20 or 30 years to develop the technology to fully support current populations.
    We might at least entertain the notion of scaled-back, local neighborhood resilience just in case the miracle we are hoping for does not come.

    • Error: Unable to create directory /home/worldsci/public_html//wp-content/uploads/2014/04. Is its parent directory writable by the server? Fred Pearce

      Yeh, climate change is going to hit us. But it’s not an on-off switch. Even if we start acting late, it will be better than not acting at all. I think we do know the technologies we need. Wind and solar, nuclear (not my favourite, but it would help) and so on, plus all the technologies to reduce energy need, many of which are very quickly cost-effective. Local resilience is good, so long as it isn’t just pulling up the drawbridge and to hell with the rest of the world…

  4. Joe McInerney

    According to the World Resource Institute’s “Earthtrends- Meat Consumption: Per Capita” North Americans consumed 123.2 Kg per person in 2002. Sub-Saharan Africans consumed just 13 Kg. That means it would take nearly 10 Africans to match the consumption of just one U.S. citizen. The biggest environmental problem is modern industrialized production, distribution and consumption that externalizes costs onto future generations to create unfair profits for the few. Free market capitalism as guiding principle is a suicide pact.

    • Error: Unable to create directory /home/worldsci/public_html//wp-content/uploads/2014/04. Is its parent directory writable by the server? Fred Pearce

      Yup, unless we can harness it so people make more profits out of being green, through green taxes and that kind of stuff. My hunch is we will only fix this if we can manage that trick. I guess the good thing about the meat story is we already know we can feed 10 billion people. We already produce enough grain to do that — but half of it is then fed to animals (or goes for biofuels). We are not going to become vegetarians overnight, but it is a point worth remembering.

  5. Wanda Berger

    Look at Pearce’s argument this way. Consider China. He would say they didn’t have a population problem. They had a consumption problem. Moving toward one child per family has diverted them from reducing their consumption!

    Sorry, this doesn’t make sense to me.

    • Error: Unable to create directory /home/worldsci/public_html//wp-content/uploads/2014/04. Is its parent directory writable by the server? Fred Pearce

      Not sure that’s quite what i’m saying. I guess you might argue that the one-child policy helped sour Chinese economic growth (and with it, their consumption). But in the longer run it will create a fast-ageing society, which could shut off that growth, as seems to be happening in Japan today. The odd thing about the one-child policy is it maybe didn’t make a huge difference in the end. Chinese communities in east Asia outside mainland China (Singapore, Taiwan, Hong Kong before the Brits handed it back in 1997)all have fertility rates right down there with China. Lower in some cases. When the Brits handed back Hong Kong, it had the lowest fertility rate in the world (one child per woman), and I assure you they were not running a covert one-child policy.

      • Wanda Berger

        EVERY society will have to deal with an aging populace as it reduces family size and health improvements extend lifespans. The only way to avoid an aging population pyramid would be continue the existing Ponzi scheme which is unsustainable and worships population growth as necessary for economic growth.

        It is desirable to cut consumption in the developed countries but given that every newborn in the poorer countries is aiming for a higher level of consumption it is doubly important to rein in population growth where it is occurring the fastest.

  6. anthony cresto

    I generally agree with you Mr. Pearce, but there are some hurdles that will be neigh impossible for us to achieve without making a fundamental shift in what we eat. However, I do not see how we will collectively change the diet of the world, especially Americans and other Western countries. Personally I am all for a primarily grain and nut diet, but will others give up their daily pound of flesh? What in your mind would be a good way to jumpstart such a fundamental change?

    And also, with dwindling fresh water reserves in many places, the Great Plains water table for one, do we have the technology to create enough fresh water to continue producing our food?

    It’s heartening by the way to hear that we already produce enough grain to feed the world.

    • Error: Unable to create directory /home/worldsci/public_html//wp-content/uploads/2014/04. Is its parent directory writable by the server? Fred Pearce

      I am a meat eater. But not every day. But i do see a growing number of vegetarians out there. (Mind you if they just replace meat with dairy products, the environmental gains are quite small.) Even so, it is not inevitable that rich people are the biggest meat eaters. Social changes may happen to reduce our enthusiasm for meat. They need to. If you really want to jump-start a big change in diet, I’d recommend a disease scare tied to meat. Remember BSE?
      Right with you on water. Wrote a whole book about that (When The Rivers Run Dry). The good news here is that we waste water so much in agriculture (which is the biggest water user), so we could be MUCH more efficient. Drip irrigation, for instance. I think water solutions are mostly demand-side rather than supply-side.

  7. Is your conclusion that population growth is not such a serious problem limited to the issue of damage to the environment? IMO there are far too many people crowded on the habitable parts of the planet to allow the kinds of social interactions that make up vital communities. By “communities” I mean the relationships described by Martin Buber, wherein people are relating who know and personally depend upon one another.

    • Error: Unable to create directory /home/worldsci/public_html//wp-content/uploads/2014/04. Is its parent directory writable by the server? Fred Pearce

      Well, it’s a crowded planet. World population increased four-fold in the 20th century, but probably won’t increase 40% in the 21st century, and could be falling by the end. Population matters, but sheer numbers isn’t the big issue now, i think. On social interactions, people seem to quite like living in cities (most of us now do, worldwide). It’s socially different for sure. Maybe on the scale of the change when we went from hunter/gatherers to farmers. Maybe not for the better, but we left the Garden of Eden long ago!

  8. Daina

    We need to keep focusing on lowering the world population because overcrowded conditions would still increase conflict (especially if there is limited access to water, food, or land). Although the world population level is believed to be decreasing, I still notice that even the affluent in America still have a relatively high percentage of “accident” pregnancies. This is particularly true immediately after a pregnancy, when even the “educated” are careless and don’t know when the woman is ovulating. For that reason, it is obvious that there needs to be a revision of sex ed worldwide. As a sex educator, I believe we are on the right path, with some success thus far, but we still have to keep working on education.

    • Error: Unable to create directory /home/worldsci/public_html//wp-content/uploads/2014/04. Is its parent directory writable by the server? Fred Pearce

      Right with you on sex education. It’s a human right to have the knowledge to plan pregnancies. And, with fertility rates halved globally in a generation. it is clear you guys are on the right track. But let’s do it as a human right not a social obligation.
      Incidentally, not sure crowding creates conflict. Most cities (not all, of course) are relatively well-ordered places, whereas some of the world’s most violent and unstable places are thinly population.

  9. Joseph meisenhelder

    Humans are large animals and a large number of them always has had a big impact on the environment. I see us continually finding that the answers humanity finds to its survival problems end up failing in the long term due to the law of unintended consequences. The only way to be fairly sure of stopping the destruction of our planet’s ecosystem is through having a small sustained population.

    • Error: Unable to create directory /home/worldsci/public_html//wp-content/uploads/2014/04. Is its parent directory writable by the server? Fred Pearce

      True, but the clever thing about humans is our ability to adapt and find solutions to problems. Sure those solutions always create new problems, and there is no guarantee we will keep solving our problems. The past is not necessarily a good guide to the future. My point is that growing human numbers is not the big issue, but of course our continued high numbers is a major factor in our current “sustainability” issues. Your last sentence leaves me scared. How do we get from here to a small population? Isn’t that the disaster we are trying to avoid?

      • Joseph Meisenhelder

        I see a small population that is gotten by means of non-reproduction as the best answer to the deteriorating planet. I think we would do well to teach ourselves that not having children is a good thing. Right now it is considered pretty much the opposite, a stigma.

  10. Dan Wallace

    In Collapse, Jared Diamond argues that the ticking time bomb is the growth in consumption that will occur as people in less developed areas pursue their natural desire and right to improve their circumstances. By his math, expected population growth coupled with an increase in LDC resource consumption to “First World” levels would have the same effect as the population growing to 72 billion at today’s consumption level.

    First World consumption will moderate, and LDCs have a long way to go before reaching First World consumption levels. So 72 billion may be an outside and unrealistic number – But “unsustainable” would occur at a much lower number.

    I’m interested in your thoughts and reaction. Thanks.

    • Error: Unable to create directory /home/worldsci/public_html//wp-content/uploads/2014/04. Is its parent directory writable by the server? Fred Pearce

      Yes, we are way beyond the planet’s carrying capacity for western lifestyles using current western methods of providing those lifestyles. But the final element in the equation — after our numbers and our consumption patterns — is HOW we produce the things we want to maintain that consumption. That to me is where the real action has to be. Generating energy without burning carbon; using energy much more efficiently; “closing the loop” by recycling key resources like metals and water; nurturing soils and ecosystems that provide vital planetary services. And we can do it.

      • Dan Wallace

        Agreed. . .no question that HOW MUCH we consume is derivative of HOW we produce what we consume. What I found interesting (and frightening) about Collapse was the examples of how slow we are to figure out where the danger points are and do something about them, often waiting until it’s too late. So I appreciate your optimism and sure hope you are right! An easy example. . .the world pays Saudi Arabia to produce oil. We haven’t yet designated oxygen as a scarce and critical resource, but it is, and Brazil produces some huge percentage of it. Shouldn’t the rest of the world be paying Brazil to continue doing that (i.e., not bulldozing the rainforest)?


  11. Sir – Although you claim that we are defusing the population bomb and seem to largely dismiss the implications of still more billions (numbers 8 and 9) by 2050, those dismissals are less comforting if we contemplate the ENORMITY of each of our added billions.

    For insights that differ from your own – such as the truly ENORMOUS size of a billion, possible implications of potentially startling advances in life-extension, population calamities in largely “empty” environments, and why current 10% conservation goals are not enough, we offer posts at: Lastly, there is a graph here: that does NOT look bomb being defused, but instead looks like the late-phase fission events inside a nuclear detonation.

    • Error: Unable to create directory /home/worldsci/public_html//wp-content/uploads/2014/04. Is its parent directory writable by the server? Fred Pearce

      Fair points, of course. But my argument is that the rate at which we are adding numbers is starting to decline. Not just in percentage terms, but in actual millions per year. And we can see a likely end to growth. Peak population, in other words. So we do not have to foresee our efforts to solve the big problems like climate change always being undermined by continuing population growth. Those who think we are doomed by exponential population growth are plain wrong. That doesn’t fix the problems, but it makes it easier to see how we could fix them.

  12. James A Gonsman


    I disagree. Climate change is not the only gun we have to our heads. We are also at the beginning of the next great extinction event, the last occurring 65M years ago. This bodes very badly for people.

    The cause of this extinction is principally the loss of suitable wild habitat resulting from agricultural development among many other human activities. In this country, 41 percent of our land mass and much of our fresh water is devoted to agriculture and, still, we import much of our food. We can wish for people to change their habits allowing us to be more efficient, but we can not stop eating.

    You can propose that humans will curtail or modify their habits, but will they and will that be enough. I think not, and what exactly is the down side in reducing the human population.

    • Error: Unable to create directory /home/worldsci/public_html//wp-content/uploads/2014/04. Is its parent directory writable by the server? Fred Pearce

      I agree with you there is no guarantee of success. But peak population will help. And I agree climate change is not the only challenge. An interesting paper published in nature magazine last year argued that we had exceeded what you might call sustainability limits in three areas: climate change, biodiversity loss and pollution of the environment with nitrogen (creating dead zones in the oceans and such).

      • James A Gonsman

        Thank you, Fred, for the reply. I did not read the Nature Magazine article but I agree with the arguments that you attribute to it. I would add that there are many serious water pollution problems beyond nitrogen including acidification that is, of course, related to carbon emissions.

        I would still like to hear your thoughts on the benefits of a larger human population or, the other side of that coin, the down side of reducing population.

  13. Error: Unable to create directory /home/worldsci/public_html//wp-content/uploads/2014/04. Is its parent directory writable by the server? Fred Pearce

    Further to Dan Wallace’s follow-up… Yes, Collapse is very instructive. As he puts it societies sometimes “choose to fail”. They just can’t get their heads round the problems they face through failures of institutional structures and politics. Ring any bells? In the past, of course, if one society failed by screwing up its environment, another could prosper elsewhere. But now we have a global civilisation. That raises the stakes, somewhat…

  14. Kim Wanzenberg

    World population continues to grow, even if it is slowing, and most of those people want to live in a comfortable Western style with cars, central air and lots of electrical gadgets. Population and consumption are inextricably bound by human nature. We can sustain a large population, barring disasters like those related to global climate change, but only if we continue to use vast amounts of coal and oil for fuel and fertilizer. Relying on technological advances is irresponsible; it relies completely on the unknown and punts a growing problem to future generations.

    • Error: Unable to create directory /home/worldsci/public_html//wp-content/uploads/2014/04. Is its parent directory writable by the server? Fred Pearce

      I think we’ve always relied on technological advances. Ever since the day we gave up hunting and gathering for farming, we have been on a technological treadmill. We can be smart about it, or dumb, but we cannot avoid it. We absolutely don’t have to rely on coal and oil in the long term. If we do, we are in real trouble. If we do, then malthus will be proved right after all!

  15. JonSax

    Urban sprawl and living in a hotter & hotter world next to millions more people doesn’t sound like the future I want.

    Like the previous person stated population and consumption are “inextricably bound” and as we put more and more humans out there will be less and less other species. Right now certain wild fish are no more – commercial fishing has wiped this out in certain ocean regions. We are polluting the ocean. What’s the matter with controlling human population? How can one justify large families anymore? Where are the farms that need this family labor?

    • Error: Unable to create directory /home/worldsci/public_html//wp-content/uploads/2014/04. Is its parent directory writable by the server? Fred Pearce

      Sure, but it may be what we get. I imagine that when hunter-gatherers watched the first farmers they would have reacted in the same way you do to urban sprawl. It was harder work in a nastier environment. But it sustained more people, and that’s what they mostly got.
      My argument about population is that fertility rates are falling so fast, it is hard to see what more could be done other than meeting demand for family planning services etc. Controlling population in the sense the Chinese do is abhorrant, and often counterproductive because of the backlash it creates,eg India after compulsory sterilisation in the 1970s.
      Re farms: mostly when people don’t need their kids on the farms (which is increasingly the case) they start having fewer kids. No compulsion needed.

  16. Error: Unable to create directory /home/worldsci/public_html//wp-content/uploads/2014/04. Is its parent directory writable by the server? Fred Pearce

    In response to James Gosnman… James, i think we can agree that in general more people creates problems when a system is under great stress as it is now. I am simply arguing that, right now, rising consumption is the big threat. Economists say the world’s economy will likely grow by 400 per cent by 2050. Of that a max of only a tenth (40%) will be due directly to increased numbers. Sure, the poor world where the extra people will be will certainly want to get richer. But they will likely adopt Western routes to wealth. So the onus both practically and morally, is on us in the already rich world to change that template.

  17. Christina

    Fred is correct about the population part of the equation, and the people who continue to consider “over-population” the biggest problem are incorrect. Population isn’t the main cause of our worst problems, and population control won’t by itself solve any of our problems. As Fred says, we have enough food for all of us, but the richest among us hoard it and waste huge amounts of food every day. Ever look in a supermarket dumpster? If the rich countries started conserving energy and reducing their consumption (our economy does not have to depend on it), and reduced our demand for exotic, out-of-season food, the poorer part of the world could go back to feeding themselves instead of gorging us. War is not caused by over-population, but by our horrendously inequitable politics and economics.

    • Error: Unable to create directory /home/worldsci/public_html//wp-content/uploads/2014/04. Is its parent directory writable by the server? Fred Pearce

      Christina, i agree with most of this. though personally I don’t think we should shut down all international food trade. In parts of Africa right now, it is a way out of poverty for some. Some of us have argued for “trade not aid” to help Africa. So it would be illogical then to snub trade with Africa, which right now is mostly in foodstuffs. Big picture, you may be right. But I fear some of the short-term consequences.

      • Christina

        I never said shut down trade or even all food trade. I was talking about the difference between “free” trade and fair trade. People who used to grow their own food (and could grow extra to sell, either domestically or internationally) had been pulled into an inequitable. forced to spend all their time growing cash crops for too low wages, situation, that we, the rich countries, the World Bank and the IMF, had imposed on them. And then we blame them for starving. I agree with “trade not aid,” but it must be fair trade.

  18. DJ Brasier

    Although there is no question that the richer countries contribute much more to CO2 emissions than poor countries (total and per capita), I wonder if that balance may change in the coming years. Two issues come to mind: the first is industrialization of the developing world (it is getting more developed after all), which I suspect would tend to raise per capita CO2 emissions to levels closer to Western countries. The second issue is deforestation: I believe developing countries have a higher proportion of CO2-eating forests, but as they develop they are cutting (or worse, burning) these forests. If this practice continues how will it contribute to CO2 emission from the developing world both in CO2 released and CO2 failed to be absorbed? How does increasing population affect that increase?

    • Error: Unable to create directory /home/worldsci/public_html//wp-content/uploads/2014/04. Is its parent directory writable by the server? Fred Pearce

      On forest, you are right for sure. Though some forested countries are now trying to curb forest loss. I agree population is an issue there, but most of the big forest destruction is by plantation owners and cattle ranchers rather than hungry people looking for land.
      Yes, developing countries want to get richer. They will try and adopt western models for doing that. We have to change the western model. In some ways it is happening. But not fast enough. The moral is that the onus is on us to fix the consumption model, rather than on the poor world to fix population (which is being fixed anyway by their women).

  19. There is a concept called Carrying Capacity that is most often applied to livestock. It attempts to quantify how much land it takes to support a unit of stock, for example, a cow-calf pair. This concept can also be applied to humans, and has been in a book, Our Ecological Footprint, written at the University of British Columbia in 1996. This study addresses the land area needed to support humans living the lifestyle of British Columbia. It does not address the requirement that land be used sustainably, nor that some land can support no human need. In a subsequent paper, Revisiting Carrying Capacity: Area-Based Indicators of Sustainability, one of the authors, William E. Rees, estimates that it took approximately 13 acres (5.1 hectares) to support someone in the United States in 1995, and that we have approximately 7 acres (2.81 hectares) of ecologically productive land per capita. So, right now, the U. S. has double the population it can support, and this still does not address sustainable usage.

    Rees goes on to say that, if the population of the world were to be living at a North American consumptive lifestyle of 4.5 hectares each, we would now need a second planet to support it, if not sustain it. Our advanced technology makes it possible for us to extract resources now that future generations will need, thereby putting off the day of reckoning until the current population is off-stage. That makes it easy for us to live with our caprice, but it’s quite a bow-wave of disaster that we are building. Population pressure is the single factor that adversely impacts every problem we have: food production, water availability and purity, air pollution, housing, destruction of other species, consumption of irreplaceable resources, everything. To assert that population will crest and then shrink if we do nothing is just another way of avoiding our self created problems. Think about the reasons that population might crest: famine, war, epidemics, etc. Sure. Let’s ignore it.

    • Error: Unable to create directory /home/worldsci/public_html//wp-content/uploads/2014/04. Is its parent directory writable by the server? Fred Pearce

      The ecological footprint analysis you talk about is valuable and shows the fix we have got into. But i don’t think population pressure is the top issue now. The growing human footprint has more to do with the increasing footprint of the average individual than the increasing number of individuals.
      Crude carrying capacity analysis assumes some fixed impact of an individual. But it isn’t so. A pre-industrial world could support many fewer people than an industrial world. We are now exceeding the world’s carrying capacity for an unreformed industrial model, So we need to move on and do things better. In a “sustainable” world the planet’s carrying capacity would be much grester than it is now. That’s our challenge.

  20. Ceecee

    Of course it’s consumption. We in the U.S. make up a very small percentage of the population but consume a large portion of the world’s resources. We have much to learn from places like India. unfortunately, instead of adopting their lifestyke they are adopting our life style. How sad. The industrial revolution in england doesn’t look so great now does it?

    • Error: Unable to create directory /home/worldsci/public_html//wp-content/uploads/2014/04. Is its parent directory writable by the server? Fred Pearce

      It’s too late to go pre-industrial! But I absolutely agree we have a huge amount to learn from low-impact “Indian” lifestyles. For a start, they didn’t throw anything away. Everything was recycled.

  21. You seem to minimize the implications of billions numbers eight and nine that are on-track to join us by mid-century, suggesting that the environmental impacts of the ‘poor half’ of the world should not be particularly worrying.

    Yet, if world population were to stabilize right now, the industrialization of the ‘poor half’ of the world (3.5 billion) would double the impacts that today’s industrialized nations are already exerting (and that is with no further population growth). A weakness in your position?

    Secondly, today’s poverty and population growth in the ‘poor half’ of the world is resulting in poaching, turning forests into charcoal, wildlife into bushmeat, and poisoned carcasses to kill lions. How is this to magically improve with two additional billions by 2050?

    • Error: Unable to create directory /home/worldsci/public_html//wp-content/uploads/2014/04. Is its parent directory writable by the server? Fred Pearce

      You are right, of course. But it underlines my point that consumption is what matters now. Future consumption in the poor world as well as current and future consumption in the rich world. The things you list in your final para are bad news, but essentially impact on local environments rather than globally. More people in poor countries has huge potential to impact local environments. But global impacts are small, and mass deforestation as generally to supply export markets — see Brazil and Indonesia today.

  22. James A Gonsman


    This is my final thought, but first I would like to thank you for participating in this discussion. Most writers just put it out there and walk away. It is rare to have a conversation. Thanks.

    I think no one disagrees with you that consumption is culprit. Most, however, are trying to point out that there is an essential and unavoidable link between people and consumption. In the developed world, we may be able to somewhat reduce consumption without giving up all prosperity and, in the developing world, prosperity may be achievable through a new template but this will be a tough and slow process. In my view, any gains in controlling (reducing) consumption by those that now on the planet will be swallowed by adding another 3 to 4 billion people and time is running out.

    • Error: Unable to create directory /home/worldsci/public_html//wp-content/uploads/2014/04. Is its parent directory writable by the server? Fred Pearce

      We are agreeing more than disagreeing. I don’t think there will be an extra 3 billion, let alone 4 billion. UN projections reckon we will go from the present 6.8 billion to 9.2 billion (an extra 2.4 billion). My own judgment (it is only that) is that fertility rates are falling so fast and so far than we may peak well below 9 billion. But i don’t want to deny the link between people and consumption.
      It is a matter of emphasis, but also of morality. I am especially troubled by people (not you) who try to shuffle off rich-world responsibility by blaming poor world “overpopulation”, and by those who think we cannot solve the world’s problems because of ever-rising population.

  23. tom ballard

    I think we are in trouble until we artificially control population. If there is no control, population naturally tends to grow until the quality of life is bad enough to slow growth. Following this line of reasoning, we should halt population growth when the growth rate is maximal, since that is when living is the best. Without control, what forces are supposed to drive population toward a desirable level? The tragedy of the commons and genetic survival of the rampant propagators suffices to make common sense ineffectual. Given that, I can’t imagine that Malthus can be wrong long-term.

    • Error: Unable to create directory /home/worldsci/public_html//wp-content/uploads/2014/04. Is its parent directory writable by the server? Fred Pearce

      Actually, Tom, i think the evidence is we are shutting down population growth before reaching any Malthusian crunch. And it is being done voluntarily, by people (mostly women) making choices about their own lives. Not by “artificial” population control. Malthus was not an ignoramus, and he had important insights. But the outlook is not as bleak as he proposed. Nor as Paul Ehrlich proposed in the 1960s, when he said in his book The Population Bomb that billions would be dying of hunger by the 1980s because the world could not feed them.

      • tom ballard

        In the first place there are already something like a billion hungry people. Whether that qualifies as malthusian I don’t know know, but it IS suboptimal. It appears that other factors such as soil erosion, the energy crisis and especially global warming are going to drive the carrying capacity down in a hurry making it seem malthusian enough for anybody. Also it seems obvious that cohesive groups with high growth rates will come to dominate the population and overcome any shutting down of growth. You might examine Utah as an example.

        I’d also like to mention that even Malthus being wrong wouldn’t mean we shouldn’t be coercive about population. The point should be to have high quality lives and sustainability not stuff the phone booth most effectively.

  24. I am fascinated by what you’ve come up with, Fred. Coming from my end of the planet, in Togo, West Africa where over population is real, I receive your findings with mixed feelings. I advocate reduction in childbirth in our community where polygamy reigns and where one man can marry more than three women. Parents continue having children though their children are having grand children. So how do we let off overpopulation as a culprit in our predicament. I think the solution would be to attack the two ills, over consumption and over population with the same zeal.

    • Error: Unable to create directory /home/worldsci/public_html//wp-content/uploads/2014/04. Is its parent directory writable by the server? Fred Pearce

      I am sure some of my stuff is a bit hard to stomach in West Africa. You are in one of the diminshing parts of the world where fertility rates are still v high and population growth clearly a massive issue. I would not think of discounting population growth as a culprit in the country’s predicament, though i’d be interested in your views as to whether bad governance isn’t a bigger problem. Togo isn’t “overpopulated” by comparison with many Asian countries. Also, I suggest that the impacts, though very real, are largely local. Togo isn’t trashing the planet the way Americans are! But I’d be very pleased to discuss this further…

  25. Steve Bismarck

    Trying to factor out population size as a discrete environmental issue is a faulty conception from the onset. Global climate change, peak petroleum, air pollution, loss of biodiversity, collapsing fisheries…these are all “population issues.” None of them would be a problem on a planet populated by 100,000 humans. Unhealthy population size is the factor that has caused and continues to potentiate EVERY ENVIRONMENTAL CRISIS WE FACE.
    At the simplest level of analysis, our aggregate consumption footprint is expressed by the formula F= a x n, wherein “a” represents the average per capita footprint and “n” represents number of people. “F” will still increase with diminishing “a” where “n” is increasing at a higher rate. We have to reduce both “a” AND “n” for a meaningful reduction in “F.

    • Error: Unable to create directory /home/worldsci/public_html//wp-content/uploads/2014/04. Is its parent directory writable by the server? Fred Pearce

      Sure, but i am trying to assess priorities. We are where we are, with almost 7 billion people. Unless you are planning a mass cull, we have to deal with the crisis it has created. If people worldwide were still having five children and most of them were surviving, then population would be a top priority. They aren’t. Fertility is falling as fast as the population “controllers” of a generation ago could have hoped. And without compulsion, by and large. Let’s build on that and rejoice that peak population will be here soon.

  26. Error: Unable to create directory /home/worldsci/public_html//wp-content/uploads/2014/04. Is its parent directory writable by the server? Fred Pearce

    I agree absolutely on fair trade, and sorry if (in my desire to get over a point) I misrepresented what you said.

  27. While this forum has a rather dismal view of the future, I continue to be hopeful because of one fact: more people more ideas. Technological progress is integrally linked to the size of the contributing population, a number which has been continually increasing. This progress has enabled us to increase the earth’s carrying capacity by increasing knowledge of genetics and ecosystems. Many believe that progress spells doom of the environment, however the industrial revolution has passed and it made us better. We are now equipped with the tools to begin a sustainable revolution. As a college student I see how excited my classmates and I are about developing technologies that can maintain our quality of life while minimizing our overall footprint. It’s all about energy, go nuclear [HRE].

    • Error: Unable to create directory /home/worldsci/public_html//wp-content/uploads/2014/04. Is its parent directory writable by the server? Fred Pearce

      yes my optimism is based on this. Sure we have more mouths to feed, but we have more hands to work and more barins to think as well. There is also good historical evidence for saying that it is when we are under greater pressure that we best innovate. Of course none of this guarantees success. As Jared Diamond has vividly described, civilisations do fail — often because they lose the ability to address and respond to the problems they face. But your sentence “we are now equipped with the tools to begin a sustainability revolution” is for me right on the button.

  28. Error: Unable to create directory /home/worldsci/public_html//wp-content/uploads/2014/04. Is its parent directory writable by the server? Fred Pearce

    I want to respond to Steve Bismarck’s comments above. Steve, I appreciate the thoughtfulness of what you say. I don’t think it is a red herring to “relatocate” one family to Africa. I was trying to more accurately reflect the world as it is. Burgeoning population growth is now almost exclusively in the poor world. In that context the amount of “resource privation” a rich-world family would need to offset a single child’s footprint in the poor world is extremely small. My TV left on standby has a bigger carbon footprint than hundreds of millions of Africans.
    Of course poor people want to get richer, but they will do it by adopting the dominant mode — the way we in the already rich world got rich. So the onus is on us big consumers to change that mode.

    • Steve Bismarck

      Are we not talking about our own peoples here? We can do more than attempt to influence population/consumption ethics in those lands which we ourselves inhabit.
      On the one hand, you point out that burgeoning population is almost exclusively a poor world phenomenon. On the other hand you point out that the average per capita footprint is much higher in the richer nations. Putting those two things together tells me that minor reductions in Western birth rates are as valuable as are quantum reductions in developing nations. The U.S. is on its third consecutive decade of rising birth rate. It is currently 2.03. If we could bring that closer to the 1.4 of Western Europe, how many endangered sea otters, falcons, and wolves could be spared from displacement by already supernumerous humans?

  29. Error: Unable to create directory /home/worldsci/public_html//wp-content/uploads/2014/04. Is its parent directory writable by the server? Fred Pearce

    Thanks for some great comments during the week, some of which made me think hard. A real debate.
    Let me end on something about optimism and pessimism.
    Pessimists are great at telling us where we are going wrong. Three cheers. They are a problem whenver they suggest we are doomed. Then they invite cynicism and a “head for the hills and damn the world” mentality.
    Optimists are great at explaining how we can come up with solutions to our problems. And a real pest when they suggest that we don’t have problems to solve and can carry on as before. So we need both. Pessimists to explain the problems and optimists to devise the solutions. None of this says we are not in deep trouble. All of this says we are not doomed. Our future, as a species, is in our own hands. I hope.

  30. Great podcast. Thanks for all that you present. I get behind and don’t have time to comment on the blog, but I thought you should know that it is appreciated.

  31. RJWill

    Even with the population we have now I see serious future energy problems. China’s population is quickly adding cars at a phenomenal rate. They have already surpassed us in total number of cars and are increasing sales some months at 30%. Their use of oil combined with India and our use is increasing the demand at the same time that the supply supposedly has peaked. Even the oil companies say we may have only 20 years left before there are serious world shortages. Small, short range electric cars can not replace the trucks and larger vehicles we are accustomed to. This will be a world event when the next and possible final oil crisis hits and we are not prepared for it in any serious way. It could bring our entire economy down with no way to get out. How do you see this scenario?

  32. ED COX

    consumption urge decreases as the feeling of well being increases – smoking pot will help – perhaps the obvious should be discussed openly


  33. I have been off this discussion for some time but just tumbled on it again while trying to google out something. Well Fred, I can’t disagree with you when you mention things like bad goverment our end. We are still experimenting on what good goverment is and we still have a long way to go. The reality of the globalised effects of the minute things that each and everyone of us do at our individual corners of the world does not allow us to let off negative phenomena like polygamy and indiscriminate childbirth as it is happening here. J ust one example is the crowd on the human trafic routes from West Africa, through the deserts ,across the seas to Europe and later into the Americas. So you see, we are also fueling anything that is happening in the developed countries.

  34. What the maximum carrying capacity of our planet is we do not know. What we are already experiencing is that given how we are now organized (i.e., our socio-political arrangements and institutions, as well as our economic systems) our footprint on the earth is stressing the delicate balance of life support that evolved over millions of years. If we do not significantly reduce our numbers AND change our behaviors by deliberate actions, nature will return the balance by eliminating us as an invasive species.

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