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Will birth control solve climate change?

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An additional 150 people join the ranks of humanity every minute, a pace that could lead our numbers to reach nine billion by 2050. Changing that peak population number alone could save at least 1.4 billion metric tons of carbon from entering the atmosphere each year by 2050, according to a new analysis—the equivalent of cutting more than 10 percent of fossil fuel burning per year.

"Demography will matter to greenhouse gas emissions over the next 40 years," said Earth systems scientist Brian O’Neill of the U.S. National Center for Atmospheric Research, lead author of the analysis, in a statement. "If global population growth slows down, it is not going to solve the climate problem, but it can make a contribution."

O’Neill and his colleagues paired data from national household surveys in 34 countries with a new economic model—the Population Environment and Technology (PET) model—to estimate the impact of various population growth scenarios on greenhouse gas emissions. The model also took into account changes in the makeup of that overall population, based on United Nations data, such as the aging population of Europe as well as the rapidly urbanizing one of India.

That urban growth—roughly half of humanity already lives in cities for the first time in recorded history—may lead to a big increase in greenhouse gas emissions. As urban residents enter the middle class, particularly in China and India, they increase their consumption of energy and transportation. "Urban living can be more energy efficient," the authors write in the analysis published online in Proceedings of the National Academy of Sciences on October 11, but increased income results in "increased emissions."

At the same time, the mellowing that comes with age in industrialized countries could cut emissions from countries such as those in the E.U. by as much as 20 percent. At least that’s true if present retirement ages and the like remain the same; "if retirement is postponed," the scientists note, "the emissions-reducing effect of aging that we find here will be lessened."

Overall, curbing population growth could reduce greenhouse gas emissions; reducing peak population to roughly 8 billion, for example, could save 29 percent of expected greenhouse gas emissions. Economic growth seems like one way to accomplish that, considering that rising wealth has historically slowed birth rates. But O’Neill and his colleagues warn that, if fewer but richer people consume more—as current consumption patterns in places like the U.S. suggest—those greenhouse gas savings become increased emissions.

Ultimately, family planning alone—such as the use of condoms and other reproductive health services—in parts of the world with growing populations, including the U.S., could restrain population growth significantly, this analysis finds. It would appear that we’re trying, thanks primarily to ongoing efforts to enable women to take control of their own lives through education and other methods. Already, birth rates the world over have halved from an average of five children per women to just 2.6 today—a baby bust replacing the baby boom.

Image: © / Nikada

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  1. 1. allotrope 5:40 pm 10/11/2010

    Perhaps this is something developing nations could use as a trading point at climate treaty talks… curbing population growth in exchange for higher emissions limits as their economies grow.

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  2. 2. graphicconception 5:58 pm 10/11/2010

    Is 9 billion such a big number? I think that if we all stood close together we would easily all fit into Rhode Island.

    Also, some estimates say that the total weight of all the ants in the world is about 10 times that of the total weight of all the people. Total krill weight is also about twice total human weight.

    Are we really significant or do we just think we are?

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  3. 3. eco-steve 6:24 pm 10/11/2010

    In every country where old age pensions were introduced, family sizes reduced dramatically. Therefor, if we provide welfare for all the world’s old people, we will solve the demographic crisis which will in turn reduce climate change and also take the pressure off ressources. It is only a caring society that will take care of the planet. Our present ‘democratic’ system has led to one billion people being left to starve.

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  4. 4. hotblack 6:47 pm 10/11/2010

    A: Probably not, since most of the people on earth simply live to eat, breed, & die, and have even adopted entire believe systems based almost entirely around encouraging that dynamic with militaristic determination.

    Time to whip up a batch of airborne human sterilization virus and let it fly.

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  5. 5. candide 6:53 pm 10/11/2010

    Neither ants nor krill have developed machines that pollute the air, and ‘magnify’ their presence.

    It is the human ‘extensions’ and energy requirements (and what is needed to get and produce that energy) that is the so-called rub, not out weight, breathing, etc.

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  6. 6. scientific earthling 8:54 pm 10/11/2010

    Everywhere today I read about a slowing rate of population growth and how wonderful, it will stop global warming. Not true. The current global population is unsustainable.
    Population is the primary driver of human induced rapid climate change; the current population is unsustainable and will positively lead to our extinction in the near future. Not a bad outcome considering the number of species we have driven to extinction.
    The world temperature is not increasing now because of the presence of ice. The temperature deferential is slowly increasing causing faster movements of energy resulting in storms and more violent weather events. Every gram of ice at 0C that melts into water at 0C has an entropy increase of 80 calories, no temperature change. When there is no more ice the same energy will heat water from 0C to 80C. That’s when warming begins.

    Worse still is the impact of religion on human society. In democratic states we face a race with one religious group trying to out-breed the rest and then establish a mono religious theocratic state and kick out democracy. Take a trip to Europe.

    A birth rate of 2.6 is still too high, remember its a fudged number from the greatest liars in the world the United Nations.

    hotblack, candide we are fighting a loosing battle. Eco-steve read candide’s post. Hopefully we shall be dead when things go real bad.

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  7. 7. jtdwyer 3:01 am 10/12/2010

    Most of the world’s population is contained in the ‘developing country’ category, indicating that they aspire to significantly increase their per capita consumption of energy, water, food, T.V.s, plastic wrap, etc., to the level of ‘developed countries’.

    Unfortunately, the consumption of nonreplenished potable water alone, by people, food production and industrial manufacturing, by populations that now enjoy the lifestyle associated with residing in the ‘developed’ category of countries, make that lifestyle unsustainable for the populations that now enjoy it, much less for the additional people who understandably aspire to it and for any unborn additional population.

    Just running our of potable water will produce a devastating catastrophe for the fortunate populations of ‘developed countries’. This will increasingly occur, perhaps most noticeably beginning in the Southwestern U.S.

    Running out potable water will significantly reduce our production of food, now dependent on highly stressed methods of optimization to meet demand.

    I’ll just cut to the chase:

    – The production of resources consumed by the current populations of developed countries cannot be sustained.

    – The resources necessary to improve living conditions for the current populations of developing countries cannot be produced.

    – The resources necessary to support the survival of additional population growth will not be available.

    The question is not whether reducing the rate of population growth will halt global warming, the question is: how many people can be effectively survive in the conditions produced by global warming?

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  8. 8. Forlornehope 4:38 am 10/12/2010

    As each US citizen produces ten times as much greenhouse gas as an African and twice as much as a, prosperous, European, you know where to start.

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  9. 9. jtdwyer 7:42 am 10/12/2010

    We could significantly reduce our GHG production by reducing our agricultural production for export. When the water runs out this will likely be our first response.

    By the way, you failed to mention the Chinese. I understand they have invested heavily in coal fired power plants. Where do the Australians fit?

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  10. 10. Sisko 10:02 am 10/12/2010

    @jtdwyer- I do not understand your degree of concern regarding potable water specifically. If there is sufficient energy why would there be a water shortage? What makes you believe there would be a "critical" water shortage in the US in the next 100 years?

    I do believe that the levels of consumption of non renewable resources on a "per person basis" in developed countries will inevitably be equalled by the populations in currently undeveloped countries over time as the world becomes more homogenous. What this means is that currently undeveloped countries with dense populations will become extremely high consumers of resources. Consumption on a per person basis in currently developed countries will go down on some resources, but will rise on others. The atmospheric release of CO2 will not be the biggest concern effecting humans 100 years from now.

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  11. 11. phenotypical 10:07 am 10/12/2010

    The "population bomb" is a dangerous but convenient red herring.

    Western countries have leveling population growths, but their consumption continues to climb.

    Even if it were true, its timeline is still 20 or however many years out for kids born today to grow into full consumers. But we need solutions we can implement yesterday.

    Besides, the entire 6.8 billion people on our planet could all live within the boundaries of Texas – it’d be cramped, but no worse than NYC or Tokyo.

    Nah, babies aren’t the problem – it’s our own unsustainable levels of consumption.

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  12. 12. Sisko 10:45 am 10/12/2010

    Please reference the source of your data. The data I look at shows that the release of CO2 has levelled or declined in developed countries over the last 20 years.

    To not believe that human population growth is the root cause problem seems extremely shortsighted. Humans will consume resources and pollute. Those that are not doing so now, will in the future. It seems like only religious fanatics can support the idea that we should continue to "be fruitful and multiply"

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  13. 13. mavaron 10:54 am 10/12/2010

    Unfortunately the scientifics are not economists…..What the history have shown us on the last century is that there is an endless source of resources provided by the capitalistic society. While we mantain our social-political order, we will get enough for everyone and don’t worry about climate change, the data provided by the IPCC is not accurate ( I really would advice you all to read Climate of Extremes)…

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  14. 14. jtdwyer 12:24 pm 10/12/2010

    When I was born in 1950 the world’s population was 2.5 billion. It’s much more crowded everywhere, but the issue is more resource availability than elbow room.

    I wonder how many cities there are right now that are more populous than NYC was in 1950? I’d bet its hundreds if not thousands… I wonder how many cities in 2050 will be more populous than NYC is right now? Maybe none, including NYC…

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  15. 15. gelfling9 1:26 pm 10/12/2010

    I have read all the posts above me and am saddened by the amount of ‘blame’ there is being thrown about…Lets be more constructive people!^^ I agree with some argument about our numbers growing, especially when I hear of people having 13+ kids because they ‘like babies’….! My personal opinion on that is that it’s irresponsible. However, I read somewhere (sorry I cannot produce references) that the world is far more able to cope with whatever we humans can throw at it..(just thinking out loud it might have been the guy that came up with the Gaia theory…?)
    I believe in living as responsibly and respectfully as possible, but I also believe as has already been said that we overestimate our own significance in this world.
    Yes, we are causing problems with issues like over-fishing etc, but I don’t think we will be the grim reapers of our own extinction. Mother nature will be the one to carry that scythe!

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  16. 16. cbutleruf 3:41 pm 10/12/2010


    Why WOULDN’T we want to slow down population growth? This is the reason for all societal ills and the discussion needs to begin. In addition to it being the cause for many problems, who among us does not want more space to exist along with the other creatures on our planet?

    The argument that we are a parasite on this planet is not a cynic’s joke. If humans are so smart, as we claim, then why don’t we solve the problems that we have created by existing? Because we are selfish.

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  17. 17. kristi276 3:42 pm 10/12/2010

    If you are not part of the solution, then you are part of the problem.

    They say that one needs to think outside of the box, but how far outside the box should one think? An inch? A meter? A yard? A kilometer? A light year? They say that there is no problem to great that can not be overcome. Do we have the will and the conviction in order to do what must be done, or are we just going to moan, groan, whine, and finger point? Yes the world is becoming an urban jungle and the population is eating up more and more of the Earth’s natural resources, but with the race to outer space is gaining into a full head of steam; all they do is collect a bunch of rocks. Space is supposed to be for the betterment of all of mankind, but all they see is how do they become rich beyond he dreams of avarice. We have the technology to solve humanities problems, but we can not see beyond the smell of green long enough to save our own throats.

    One small step for a man. One giant leap for mankind.

    Instead of looking for a far distant planet (light years away) maybe we should start to develop in our own neck of the galaxy. We keep looking for the perfect planet to colonize that is habitable, but it is a habitable planet would it not be already occupied by who knows what (happy meal of a light snack). We have to learn to make do with the planets that we have, for if we can make it here we can make it any where. Solar development in our life time and beyond. This should be the beginning of the Solar Age and not the end of humanity, for all of these space agencies should come together and work as one in order to maximize the resources in order to achieve a common goal of development and industrialization.

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  18. 18. cbutleruf 3:45 pm 10/12/2010

    This is asinine. Krill and ants act as part of the biosphere while we abuse it ad nauseum. In addition, when their populations grow beyond their tipping point, do you know what happens the them? They are culled by the natural system. Meanwhile, we do all that we can to achieve total dominance over all organisms and it is to our own disadvantage. Maybe you think that you will not be alive for the consequences of our actions, but I argue that many are currently suffering from humanity’s assault – physically, socially and mentally (you can even add in "economically" since many presume that ACTUALLY matters).

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  19. 19. Hermit 8:14 pm 10/12/2010

    I think the main reason population growth is hard to control is that our consumptive "American Lifestyle" is addicted to population growth. The wealth generated via resource depletion is critical for us to live the consumptive way we do.

    Consider one of the "Three Pillars" of the economy: Housing. What would happen if we only built replacement houses instead of "Developments?" Where would all the carpenters, concrete contractors, etc. work? Where would we get the wealth released when the raw land is turned into a suburb? This works the same way for the other two pillars, Agriculture and Manufacturing: more people = more cars, more food = more wealth (and more opportunity to amass it.)

    We can’t live like this forever and "so far, so good" only works so long. We have to re-create ourselves with sustainable values to replace "greed is good" and conspicuous consumption as a legitimate way to get attention.

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  20. 20. Raghuvanshi1 10:48 pm 10/12/2010

    Most pollution created by developed countries. America is creating 25p.c. total pollution.Population is increasing in developing countries they are creating less pollution how can birth control is effective to control the climate change?

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  21. 21. jtdwyer 1:56 am 10/13/2010

    Sorry I’ve overlooked your question re. potable water supply concerns for so long.

    If you’ve every flown across the U.S. you may have noticed that much of the cropland in the East is neatly divided into rectangular fields. In the West much of the cropland forms circular fields on a dry dirt background. These ‘crop circles’ are produced by huge center pivot irrigation systems that use diesel or electric pumps to bring non-replenished fossil water from ancient aquifers.

    A quick look didn’t find much to support this view but a very small paragraph in Wikepedia:
    "In the middle of the 20th century, the advent of diesel and electric motors led for the first time to systems that could pump groundwater out of major aquifers faster than it was recharged. This can lead to permanent loss of aquifer capacity, decreased water quality, ground subsidence, and other problems. The future of food production in such areas as the North China Plain, the Punjab, and the Great Plains of the US is threatened."

    The major water source in the Midwest for both drinking water and irrigation is the ancient Ogallala Aquifer. That its water depth has been diminishing, requiring ever deeper wells, has been recognized as a long term problem for decades.

    In the West much of the water is produced by Rocky Mountain snowfalls, which seem to be jeopardized by global warming. As it is right now, the major delivery system is the Colorado River, which, as I understand, no longer runs to the ocean. These insecure water sources now not only supply water to the major cities but most of the the agricultural production in the Western U.S.

    I admit I haven’t thoroughly researched the current status of potable water, but I think that diminishing supplies has been a recognized future problem since the world population was somewhere around one-third of it current level. I think that the continuing increase in population and threat of global warming may exacerbate diminishing resource availability…

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  22. 22. TruthHound 2:32 am 10/13/2010

    Of course we MUST reduce population – it is simple accounting.
    However, we need much more and it has to start with addressing value systems. Selfishness or greed is not the problem – that’s nonsense, it is the strive to be better and to outcompete. You have to strive for the better car, house, lifestyle etc. That is what symbolise your worth. We need to change values and find other ways to define "worth". 150 years ago the person that could kill most antelope in one day was the big hero, today you’ll get ostracised for that.
    Time to stigmatise opulence – big cars, travel, outdoor heating, air conditioning and having lots of kids. Tax the baby makers rather than providing breaks

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  23. 23. gelfling9 5:33 am 10/13/2010

    I agree with your comment about the need to change perspectives on ‘value’ and ‘worth’. Why is it that we reward actors more highly than scientists?

    However, I don’t see that penalising people that want to procreate is the answer…why should people that want to have children be demonised? Before we start thinking along the lines of reducing our population, surely there are more immediate issues that need taking care of first like protecting the Amazon. Someone, somewhere, in some office could stop it’s destruction in an instant if they wanted to, but that would only happen if there were no longer any profit to be gained by it. One person, or one company should not have that much power that the rest of us ‘little people’ have to pick up the pieces.

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  24. 24. madmac 5:48 am 10/13/2010

    I was hardly surprised to see this wonderful piece of anti-human propaganda was written by David Biello. Inspiring the usual mix of murderous comments from salivating AGW fanatics.

    Riddle me this: How many Icelandic volcanoes would it take to entirely offset this ‘benefit’ of tearing apart families before they even come to exist?

    A large family is the most wholesome environment that one can exist in. A large family makes one less dependent on the state, social security, hospitals and nursing homes. Apparently, the entire human population of the world can fit inside Texas at the population density of London (do the math yourself).

    Let’s stop this anti-humanity and anti-family sentiment in it’s tracks. See for yourself, and acknowledge for once, just how much the humans-cause-global-warming fanatics like Biello here care about people:

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  25. 25. jtdwyer 7:08 am 10/13/2010

    It’s a real problem. Every living person requires resources including water, food and power for sustenance. As I continuously repeat, since I think that those under maybe 30 years old do not remember past conditions even in a local environment, when I was born the population of the Earth was about 2.5 billion people; it’s now nearly 7 billion.

    Do you really think that nearly tripling the population of the Earth in my lifetime has had little effect? Let’s see: the population could be returned to 1950 levels by eliminating 2 out of every three people. You don’t think that would reduce atmospheric co2?

    Curiously, you’re the second commentator to specifically state that the entire human population of the Earth would fit in the state of Texas. Quite original, huh? Again, this isn’t about elbow room, kids, it’s about resource requirements/resource availability and waste products; human suffering.

    I’m not suggesting murder as a solution, but there must be a solution or those living in the future, including my grandchildren’s unborn children, will suffer. Perhaps a method of limiting everyone to one child per person?

    When conditions become insufferable, those who are not yet dying may chose to end their lives prematurely. There are more meaningful measures of productivity, but I’m 60 years old with health issues. If we could get at least 10% of the population to commit suicide and limit everyone to one child per person, I’ll pledge to join in the effort. How’s that for a reasonably non-murderous, pro-family solution?

    Perhaps everyone over 60 years old should be peacefully, permanently retired. I don’t have the necessary population demographic data available, but that might make a meaningful contribution to the future quality of life. It’s not a murderous joke: I’ve experienced the effects of uncontrolled population growth in my own life. Hopefully my grandchildren will not: I love them and don’t want them to suffer the consequences. Get it?

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  26. 26. gelfling9 6:53 am 10/14/2010

    One child per person is not so unreasonable as that would of course equal two children per couple then?^^

    Just from the quick info obtained from Wikipedia with regard to how China has fared with this policy since 1979, the enforcement of one child per family,is scary (I’m thinking of the backstreet abortions, and children abandoned in orphanages or just left to die)! China is currently the second largest economy in the world and second largest importer of goods, I wonder what it’s postion was in 1979 and has the one child policy inadvertently helped them in some way to become a major economic force in this world? I’m just a casual reader and don’t have all the facts and figures, but according to Wikinews, in 2005 China beat the United States as the world’s biggest consumer of resources. So I’m kinda thinking…one child policy + biggest consumer of resources = ??? Basically, it doesn’t add up!

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  27. 27. scientific earthling 8:45 pm 10/15/2010

    The one child policy made education of wanted children possible. In Australia a couple has been charged with "procuring the miscarriage of a woman", they had procured and used the drugs Misoprostol and RU486 A case of religious bigotry, I am sure you would love this to happen worldwide.

    Educated populations prosper and demand more goods and services, result the country has been booming. They don’t have democracy to slow down scientific progress either.

    Lower population and education improves living standards and demand for goods and services – it all adds up perfectly well. China is now where the USA was in the days of "Popular Science" and "Popular Mechanics". I don’t suppose you remember those magazines.

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  28. 28. jtdwyer 4:15 am 10/16/2010

    I remember, and I realize that China is now the land of opportunity, with construction of new modern cities seemingly outpacing the construction of new office buildings in Los Angeles. Your point regarding lower population growth enabling education enhancements is highly perceptive!

    It seems that all those lucky, well educated Chinese people now finding economic opportunities for (relatively) good paying jobs and capital investments are also consuming much more water, food, power, etc. If that weren’t contributing massively to global warming all would be swell. Not that they should not benefit just as the developed world already has, but I think I saw where China not has the largest number of coal fired power plants in the world. China truly is at the stage of economic development that the U.S. ‘enjoyed’ in 1950. However, we now hove more information about the consequences of wanton ecological destruction: we (they) should not repeat our past mistakes.

    For the rest of the world, even if reducing population growth enables education and economic development, perhaps we can eventually develop technology to achieve these humanitarian objectives without destruction of the global ecosystem. There is little hope for that result if population continues to grow unchecked.

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  29. 29. Dr. Strangelove 11:26 pm 10/17/2010

    No, 9 billion is not a big number if humans consume as much as an equal weight of ants. A 150-lb. man drives a 500-horsepower sportscar and consumes 10 kilowatts (7.5 hp) every hour running his household appliances. A 150-lb. ant colony consumes less than 1 hp.

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  30. 30. Dr. Strangelove 11:34 pm 10/17/2010

    Correction: that’s 10 hp (7.5 kW)

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  31. 31. scientific earthling 1:27 am 10/18/2010

    Education solves most problems. An educated Chinese are now the worlds largest investors in green power, they took one of the advanced Australian Wind power companies, struggling to survive in Tasmania to China and made them one of the biggest makers of wind power generators in the world. Reason: They were educated enough to see the need, and grabbed a company for cheap that our dumb locals did not value.
    Look at India on the other hand, the number of uneducated people keep increasing every year. As the reverend Thomas Malthus pointed out in 1798 those least able to support themselves are the most prolific breeders. We can see the truth of that statement in India. They consume very little, but they still do enormous environmental damage. India can not maintain her wild life parks, since landless peasants encroach on reserves and clear the trees to establish tiny start-up villages, which grow to enormous shanty towns, there is no more land. Famine will put things right, it is the only thing that works.
    China will lower her carbon footprint, India I don’t think so. Does the world have time? I don’t think so. We are loosing ice too fast, melting ice stops temperature rises, but entropy is increasing dramatically. Every gram of liquid water at 0C has 80 calories more energy than a gram of ice at 0C. We are on the threshold of extinction, and we have done it to ourselves.
    Uncontrolled population growth aides and abetted by religion and food aid are the prime drivers of our extinction.

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  32. 32. gelfling9 3:19 am 10/18/2010

    Just to clarify, my reply was in response to jtdwyer’s post (#25) which suggested that the one child policy was a good idea.
    I appreciate the subsequent insight given, that one child families have the ability to better educate their children, though the upshot of that is also a better (damaging) standard of living. It is a paradox :-)

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  33. 33. BlueCollarCritic 6:48 pm 10/18/2010


    "It is only a caring society that will take care of the planet. Our present ‘democratic’ system has led to one billion people being left to starve."

    What? Do you actually believe what you’re selling? People have starved because of a number of reasons but Democracy is NOT one of them. The most productive and richest society to evolve on this planet is the American society and it did so because it did what no other society since Rome has and that is recognize individual property rights. The American society is on a down slide because we let the wicked and corrupt sneak in and slowly take over selling us one lie after another and slowly guilting us into giving up what we had gained.

    It is the tyrannically lead dictatorships and communist/socialist prison camps called countries that starve millions if not billions each year.

    "Only a fool believes his land will magically harvest itself and provide him with bread simply because he needs it."

    "Nature provides for he who works for his rewards while a politician works to take from him and give to those who will vote for the politicians work"

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  34. 34. Dr. Strangelove 3:10 am 10/19/2010

    If humans consume energy like other animals, 9 billion population is small. How much energy do we really need to live? The recommended daily calorie intake for an ave. male is 3,000 calories. That’s equivalent to 3.5 watt-hr in 24 hrs. or 0.14 watt. Our cell phone consumes more power at 0.25 watt.

    It’s amazing how little energy we really need yet we consume energy at an average rate of 10,000 watts per capita.

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  35. 35. jtdwyer 12:14 pm 10/21/2010

    If the current per capita human energy consumption was the same as it was during the Renaissance, for example, I suspect 9 billion people would still require a lot of power and produce a significant environmental and climatic impact. Of course, we might still be burning coal in our homes…

    I wonder how much methane 9 billion elephants would produce, and what the resulting climatic impact would be…

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  36. 36. Dr. Strangelove 11:21 pm 10/24/2010

    You don’t have to burn coal when your 100 sq.m. solar panel can produce 4 kW to power your microwave oven and heater. I bet your car produce more greenhouse gas than an elephant.

    It’s not the absolute number. It’s the consumption and technology. Given the world’s limited arable land and current food yield per sq. kilometer, we can only feed 100 billion people.

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