Why do so many think that population growth is a problem?

In TED Conversations (video no longer available), the late Hans Rosling, professor of International Health and co-founder of the outstanding interactive website Gapminder, asked, “Why do so many think that population growth is an important issue for the environment? Don’t they know the facts of demographics?” He partially answered his questions:

We face many environmental challenges, but the foremost is the risk for a severe climate change due to CO2 emissions from fossil fuels.

I meet so many that think population growth is a major problem in regard to climate change. But the number of children born per year in the world has stopped growing since 1990. The total number of children below 15 years of age in the world are now relatively stable around 2 billion. The populations with an increasing amount of children born are fully compensated by other populations with a decreasing number of children born. A final increase of 2 billion people is expected until the world population peaks at about 9 billion in 2050. But the increase with 2 billion is comprised by already existing persons growing up to become adults, and old people like me (+60 years). So when I hear people saying that population growth has to be stopped before reaching 9 billion, I get really scared, because the only way to achieve that is by killing.

So the addition of another 2 billion in number constitutes a final increase of less than 30%, and it is inevitable. Beyond 2050 the world population may start to decrease if women across the world will have, on average, less than 2 children. But that decrease will be slow.

So the fact is that we have to plan for a common life on Earth with 7-9 billion fellow human beings, and the environmental challenge must be met by a more effective use of energy and a much more green production of energy.

The only thing that can change this is if the last 1-2 poorest billion do not get access to school, electricity, basic health services and family planning. Only if the horror of poverty remains will we become more than 9 billion.

So my question is: Are these facts known? If not, why?

It is important because placing emphasis on population diverts attention from what has to be done to limit the climate crisis.



Rosling’s perspective above is shared by others and, considering his stature, is likely to be accepted at face value. It deserves deconstruction:

We face many environmental challenges, but the foremost is the risk for a severe climate change due to CO2 emissions from fossil fuels.

It might be, though one could argue that toxins and habitat loss may be equally challenging. Regardless of which man-made problem(s) we choose as foremost, population growth is indeed a major driver: the more of us there are the greater our total impact.

I meet so many that think population growth is a major problem in regard to climate change. But the number of children born per year in the world has stopped growing since 1990

The fact that our natural increase peaked in 1989 at 87 million doesn’t mean that the 80 million more of us born than die each year have no significant impact.

The total number of children below 15 years of age in the world are now relatively stable around 2 billion.

And they will be creating more of us over the next 15 years, many against their wishes or unintentionally. Our goal shouldn’t be to maintain a stable number of people under 15—we need a steadily decreasing number. A relatively stable number of children are dying each day, but stability in this situation is likewise less than ideal.

The populations with an increasing amount of children born are fully compensated by other populations with a decreasing number of children born. A final increase of 2 billion people is expected until the world population peaks at about 9 billion in 2050.

One might ask how we will increase by 2 billion if populations with “increasing amounts of children born are fully compensated by other populations with a decreasing number of children born.” This incongruity is caused by using “increasing” and “decreasing” as determinant factors without quantifying them: how much?

Included in most attempts to show that we have nothing to fear about human population density are the demographic facts that birth rates are decreasing, our growth rate is decreasing, and the sheer number of humans added each year is decreasing. There’s one fact which negates all three of those decreasing rates, and it’s usually left out: our population size is steadily increasing.

world.pop.proj.2100
World population charts.

But the increase with 2 billion is comprised by already existing persons growing up to become adults, and old people like me (+60 years).

No, the increase of 2 billion will come from the excess of births over deaths, same as it always has. Humans of all ages are included in the global census, so the increase doesn’t come from existing persons, rather from those who don’t yet exist. They won’t exist in the future if their conceptions are prevented.

So when I hear people saying that population growth has to be stopped before reaching 9 billion, I get really scared, because the only way to achieve that is by killing.

What’s even scarier is hearing prominent people whose opinions are well-respected saying that the only way we can improve our population density is by killing. Many people understandably forget that breeding adds to our population: it’s a mental blind spot. But we would expect a statistician and professor of international health to be aware of both factors determining population increase or decrease, as well as the significant ecological impact each new human will add.

So the addition of another 2 billion in number constitutes a final increase of less than 30%, and it is inevitable.

Twenty-nine percent more of us when we’re already into overshoot by 50% isn’t inevitable because both our birth and death rates are uncertain.

We’ve exploited Earth’s resources to the breaking point. Wringing out an additional 29% isn’t likely, and that would be needed just to maintain our dreadful status quo: a billion hungry and two billion without potable water. Continuing to increase demands on exhausted supplies, whether due to more people, increased standards of living, or both, is likely to increase death rates—possibly massively. We may not succeed in preventing increased deaths due to famines and conflicts over resources, but we have a moral obligation to try.

Birth rates may be voluntarily improved in many ways, so an increase of two billion isn’t inevitable. Further lowering birth rates among wealthy populations will conserve resources, with the potential for improving standards of living among the poorest in our human family. Lowering birth rates among the poor will help them live better on what they have.

Beyond 2050 the world population may start to decrease if women across the world will have, on average, less than 2 children. But that decrease will be slow.

Quite slow, and also delayed: even with a global fertility rate of 2.0 starting now, our numbers would continue to increase for decades due to momentum. China’s TFR has been well below 2.0 for over 20 years and they’re still growing by 6.6 million a year. (2022 update. Population may have begun to shrink).

So the fact is that we have to plan for a common life on Earth with 7-9 billion fellow human beings, and the environmental challenge must be met by a more effective use of energy and a much more green production of energy.

Energy is a significant resource feeding our industrial civilization and oil companies forecast we’ll use 40 percent more energy by 2030. But let’s imagine we somehow pull off that technological feat—what about our more basic needs: food and the water needed to grow it? Our present agricultural land use is the size of South America and we’ve already put most farms on performance enhancing drugs. Consider depleted fish stocks and aquifers, desertification and top soil loss—the list goes on and is ignored at our peril.

The only thing that can change this is if the last 1-2 poorest billion do not get access to school, electricity, basic health services and family planning. Only if the horror of poverty remains will we become more than 9 billion.

Ameliorating the horror of poverty by increasing living standards will be easier if there are fewer people in poverty. Don’t be scared, killing isn’t necessary. In fact, that’s already happening on a large scale and it’s not reducing the number of poor people. Gender equality and the reproductive freedom which follows will greatly reduce unwanted pregnancies and subsequent deaths from malnutrition and maternity. The basic human right to not breed is being denied with tragic consequences.

So my question is: Are these facts known? If not, why?

As Rosling demonstrates, facts alone are not enough. Even among those of us with the data at hand and the intelligence to apply it, our emotionally-embedded worldviews can overrule logic.

It is important because placing emphasis on population diverts attention from what has to be done to limit the climate crisis.

Accepting that increasing overshoot is inevitable, and pretending it doesn’t matter much anyway, diverts attention away from the human suffering that those born today are likely to experience. It also ignores the environmental degradation each of us, particularly in over-industrialized regions, is responsible for when we choose to create another human being.


The TED “conversation has closed,” so my analysis can’t be added there. A few comments countered Rosling’s dismissal of population growth and his human-centered concerns, but most agreed and many found his perspective reassuring:

With all the misguided talk of world population explosion even my own children are embarrassed by the fact that I had five kids.
Well, the data is there. Its been there for a while now. The interpretation of this data has really sucked till now! But thanks to you, we have a much better understanding of what’s really happening.
Thanks Hans, before I read your question I thought population was a very big problem, but seeing as your a world expert and reading the statements you have read. Why do so many people think this?... The important thing here is that you as an expert on this can enlighten people on what aspects of the worlds problems are most important, and help eradicate any environmental dogma.
It is amazing how easily the meme of the “Malthusian Catastrophe” spreads... I wonder what instinctive fears it is touching that makes people believe it, almost religiously, so very quickly. In any case, it seem to take an inordinate amount of time and work to dislodge it !!
One shares my opinion:
I think, the reason for this false perception about population growth may also be linked to psychological factors and not merely to the facts.
However, the “false perception about population growth” they refer to is that it’s a problem.

While there’s renewed awareness of the consequences of our excessive breeding, there’s also considerable opposition voiced by influential people. The idea that creating more of us, commonly called “having children,” could be detrimental to people and planet is naturally resisted by those who have already done so and especially by those who plan to.

The single most effective way we as individuals can conserve resources and benefit Earth’s biosphere is to forgo creating another of ourselves. In the USA, each new human we don’t create preserves 22 acres (9 ha) of potential wildlife habitat and avoids adding 9,441 metric tons of CO2 emissions.

Thank you for not breeding.


Additional note: Rosling’s curious statement that “the increase with 2 billion is comprised by already existing persons growing up to become adults, and old people like me,” might be explained with population pyramids of global population from 1950 to 2050. If one clicks on each five-year time block, the evolving pyramid gives the impression that the reason there will be two billion more is that we’re not dying fast enough: the bulge rises. Thus, global population increase comes from people already born rather than those who haven’t been born yet.

Phillip Longman, author of The Empty Cradle: How Falling Birthrates Threaten World Prosperity and What To Do About It, makes the same error: “In other places, you know, we still, to be clear, are looking at very rapid population growth that creates pressures of its own. But what’s new is that most of the remaining population growth, for the globe as a whole, is coming from people who’ve already been born.”

This convoluted thinking exemplifies the mental blind spot humanity has about our breeding. We can’t see that “having babies” might be the cause of any problem, not even excessive population density.


More from Hans Rosling:
Viewpoint: Five ways the world is doing better than you think. November 2013
Hans Rosling Professor of Global Health, Karolinska Institutet
How extreme poverty became rarer
Many people don’t know about the enormous progress most countries have made in recent decades—or maybe the media hasn’t told them. But with the following five facts everyone can upgrade their world view.
1. Fast population growth is coming to an end
2. The “developed” and “developing” worlds have gone
3. People are much healthier
4. Girls are getting better education
5. The end of extreme poverty is in sight

More analysis of the above:
From Paul Ehrlich: Confused Statistician.

Return to: DEMOGRAPHY

logo