Climate Change Could Mean More Kids, Not Less

The effects will vary across the globe and could worsen inequality.
Children walking down the street
Photo: Getty / Brasil2

Climate change threatens to affect every inch of life as we know it. Some impending disasters are obvious: rising sea levels will cause flooding, droughts will restrict access to water, and intense storms will destroy our homes and properties.

But there’s also the impact it will have on our bodies. A new paper in Environmental Research Letters, published last week, looked at one aspect of this: how global warming will influence fertility.


The researchers came to some surprising, and disturbing, conclusions. They found that global warming will increase the number of children people have, while lowering the value of education—but only in certain, vulnerable parts of the world. This would deepen already-existing inequalities between wealthy and poor nations, and the inequality between men and women in those communities.

VICE spoke to two co-authors on the paper, assistant professor of economics at Williams College, Gregory Casey, and Canada Research Chair in Energy Transitions at the University of Waterloo. They walked us through how exactly climate change might influence how many kids people choose to have, and what the consequences of that could be.

VICE: Thinking about climate change can be so overwhelming—all of the downstream effects are really hard to grapple with. Zooming in on just one potential outcome can be a more palatable way to reckon with the consequences we're going to face. You chose to look at how climate change will affect, specifically, fertility. What motivated you to look at this over the many other things climate change will impact?

Gregory Casey: Both education and fertility are very important determinants of long-run economic outcomes. When I was in graduate school, my focus was mostly on economic growth. And as I started to learn about climate change, I saw relatively little about how climate change would affect these two important outcomes, which, economic research tells us, are going to be very important for determining long-run well-being.


Juan Moreno-Cruz: I would agree and add that it's not only about fertility, even though that is the ultimate result. It's about education. And from my perspective, it was also about women’s empowerment, which comes through education as well.

VICE: Tell me, broadly speaking, what are the ways that economic factors affect fertility? Can you explain that relationship and what you call the “quantity/quality trade-off?”

GC: Quantity/quality trade-off is kind of an economic jargon term. The general idea is that we know everybody, including parents, has limited resources, both time and money. They have to make decisions about how many children to have, and how much time and money they can afford to invest in the health or education of each child. That is a standard economic problem. When the benefits and costs to investing in education change, parents tend to change their behavior. And along with those, they adjust both the number of children and the resources they can invest in each child.

From that perspective, anything that changes the benefit to a child to having education is going to affect fertility decisions as well. At a very broad level, it’s: do you live in a society where going to school is going to have high economic returns? That's going to push parents towards having fewer children and using their scarce resources to invest in education. When the reverse is true, parents are likely to use their resources to do other things, including having more children.


VICE: This is linked to climate change because, as you wrote in your paper, climate change will cause shifts in the economy. In some places, it will shift towards a more agricultural economy, and lower the value of education. Walk us through that connection: why would climate change shift an economy towards agriculture, and why would that lead to education being viewed differently?

GC: The general premise is we know, especially near the equator, climate change is going to have a big impact on the economy overall. That's especially true for agriculture, since these natural systems are so dependent on the climate. When food becomes very scarce because it's hard to produce in an agricultural sector, that's going to drive up prices and wages, which is going to create an incentive for people to move out of other sectors and into agriculture, to make up for some of the reduction in food availability.

Another thing that we know is agricultural production tends to put less emphasis on education than other sectors. When climate change increases the benefit to working in agriculture, it also reduces the benefit to getting an education. Through the quantity/quality trade-off, it creates incentives for parents to invest less time and money in the education of each child and, instead, have more children.

VICE: Juan, can you speak to what you said before, and how that shift impacts a woman's ability to work and her place in the marketplace?


JMC: It's harder to quantify, but the way I see the issue is you have to make decisions based on the amount of resources, like Greg was saying. You have some income and you need to split it among members of your family. If you live in a society where boys are given privilege over girls, then you might end up sacrificing, in principle, the education of your girls, and not boys.

Again, this is a speculative notion at the moment, but what will happen with climate change is that you now have a country that already had a set of cultural rules that favor men over women. Climate change can even further affect the allocation of resources.

If you look over several decades at economic progress from different countries, one of the clearest indicators is women participation in their location and labor force. So it threatens that channel, no?

That’s a very important channel, and it could become very regressive in bad times. We already know that climate change will affect the poor the most, but now we're thinking about how culture starts to play a role into the way climate change can manifest itself in the economy.

VICE: Let’s talk about what you specifically modeled now, because you took it beyond just these abstract speculations and really quantified these theories.

GC: Sure. From a modeling standpoint, a lot of what we were doing was pulling together two well-established sets of facts and sets of theories. The first being, there's a long literature on the relationship between economic outcomes and fertility.


In particular, we tried to mathematically quantify this decision parents have about investing in education versus investing in children. And we had a theory that there would be an importance of agriculture versus non-agricultural sectors. So we just pulled that together with some existing estimates of the impacts of climate change, all of which suggest that agriculture will be more negatively impacted.

VICE: Something that you found from your modeling is that climate change will likely affect fertility differently in different places—and it depends on a community’s relationship with agriculture or how dominant agriculture is in their economy.

GC: Absolutely. For people living in agricultural communities, when climate change comes in, it makes it even harder to produce food. That means that more people are necessary to work in agriculture to create enough food to support the population. But this drives down educational attainment and increases fertility, which kind of further exacerbates the negative economic effects of climate change, especially in these particularly vulnerable communities.

JMC: It creates that short-term impact, which is that now you have more people and you have to feed them. But also, they are less educated, so you have a long-term impact in the economy. Even if you were trying to recover from climate change, it's going to be harder.This particular feedback loop on fertility seems to be quite negative and make the impacts quite permanent.


VICE: One of the impacts of climate change that people talk about is all the migration that might happen when people's homes are no longer hospitable. We tend to think about this as an impending disaster—climate refugees. But in this case, it sounds like migration could actually be a way to escape this feedback loop?

GC: That's sort of the two sides of migration. The fact that climate change might be so bad that it creates all these refugees is unambiguously negative. But it is one way to mitigate these specific negative impacts. So it's a negative thing that it's necessary at all. But if climate change does happen, we think that migration is one way to at least mitigate the negative consequences somewhat. It'd be better off if it wasn't necessary at all in the first place.

VICE: Your model used a hypothetical economy based on Colombia, and compared it to something like Switzerland—why did you that what did you learn from that comparison?

GC: Our goal was to think about how might this effect be different in different locations, and also for places that had different levels of income. One of the most pernicious things we actually found was that there's all these negative impacts for places near the equator, which tend to be poorer and tended to contribute a lot less to total carbon emissions in the first place. But when you look at richer northern locations, the patterns can actually work the opposite way.


In some places, climate change is expected to improve agricultural productivity. It induces the exact opposite set of results, which might benefit those richer northern countries, exacerbating the existing inequality. Also, the negative consequences of climate change are sort of punishing the areas that did less to contribute to the problem in the first place.

VICE: To summarize: there would be areas that don’t need as much manpower going to agriculture once the impacts of climate change start happening. And there won't be that need to move away from education and have more bodies working in the agricultural sector. They'll be encouraged to go in the other direction, which is to focus more on education and have less children.

GC: Exactly.

JMC: The other exercise that we did was to take the country and then move it. What if Colombia was in the north? Let's keep the Colombian characteristics as a country, other than the climate, and move it to the north and see what would happen. And then what happens if you move Switzerland to the south? You are keeping a strong economic country and you're giving it the climate of a tropical country and see what happens.

VICE: And when you moved Switzerland down to Colombia and you asked, "everything is the same except now it'll be impacted more by climate," what did you find?

GC: If you take Switzerland and you put it sort of where Colombia is, you get outcomes that look a lot like Colombia's. That drove one of our main conclusions, which is that we see this big difference between richer, northern places and poorer, more centrally located places, it seems to be the geography that drives the different impact, rather than the level of development.


VICE: That seems like a really important point when we think about the inevitable, coming inequalities and biases that we have about developed versus less-developed nations. We might want to blame a country’s struggles on their level of development when actually it has more to do with geography, and if anybody was there, they would be going through the same problems.

GC: That is certainly true for our mechanism.

Though I do think there are other reasons to believe that income itself can certainly be helpful in adapting the climate change along other margins that weren't necessarily a part of our study.

VICE: All of this kind of assumes that agriculture is low skill-level or that education—at least the way we do it now—might not be as important for an agricultural economy. What if we think about a future in which agriculture gets a technological revamp and the people who work in agriculture need a high-level of education?

JMC: You could say that maybe Colombia's more affected because their machines and their technology are lower somehow, and that they are not as developed. But what we find, like Greg said, is that when we move to Switzerland—which has more advanced agricultural technology—the effect is still there. Let's say agriculture becomes all driven by AI or something and you don't need too many workers anyways, like it's in well-developed countries. Then, we shouldn’t have seen an effect on Switzerland. The evidence suggests that it is actually still there.


GC: I think if we lived in a different world where education was sort of central to the agriculture production process, the outcome might be different. For other mitigations, trade and migration seem like the obvious ones on a big picture, macroeconomic scale.

Another one that we mentioned briefly in the paper is international aid that helps bolster the agricultural sector. Rather than having to make up for the loss of agricultural output just by labor reallocation within poorer countries, development assistance that's aimed towards boosting agriculture might play the role of helping people move outside of agriculture and therefore mitigating these negative consequences.

VICE: How much promise do you feel there is in this kind of modeling you did, which looks at connections between areas that might not appear obvious, like fertility and the economy? What are some other fields that you feel should be looked at in their relationship to each other, in regards to climate change?

GC: The thing that jumps to mind is health. We know that climate change is going to have a lot of impacts on various forms on health. And we know that health has big impacts on both the economy and demographic outcomes. So integrating more of that kind of nuanced understanding of the health impacts of climate change from other disciplines, I think, can only add to our understanding of these important questions.

JMC: The part that I love the most about this paper is precisely the fact that we're asking a question that was not a pure economic question. And for that you need different disciplines. As the questions get more advanced, they will require teams of multiple disciplines to look into them. I have seen a lot more need for cultural anthropology and economics to get together, or sociology and economics, in the sense that climate change might have a more profound impact on the way we interact with each other in our society.

VICE: A last thought, going back to what I said earlier about how many of us feel really overwhelmed at the cascade of potential problems that climate change will set off. Is there any room for optimism alongside this kind of modeling? Does it give you back a sense of agency when we can try to predict what's going to happen? Or does it make you more scared?

GC: That's a very interesting question. Part of what I like about economics is agency is always part of it. We can think about what people could do or what they might do, as we were talking about before with migration. Not necessarily as a net positive thing, but at least ways to do everything we can, to adapt to or mitigate the negative consequences of climate change.

But I would say overall, certainly, the results that we found in this study were not very optimistic. And in that sense, they left me with an even more pessimistic view of the effects of climate change than when I started.

JMC: The model gives you a lot of negative outcomes of climate change, but what I see as a positive result is that humans are very good at getting out of trouble. We are really good at using our intelligence to design ways to solve problems. And we have been doing that for millennium.

Just by looking at my students and younger generations, that innovation seems to be happening at the more social structural level. We are starting to understand the value of social capital, understood our relationships with each other, and putting a higher value on those things than we used to. Climate change could push society toward a more cooperative way of solving problems, and the understanding that we are facing the same problem.

This interview had been edited for clarity and length.