A climate scientist explains why it’s still okay to have kids

In 2017, climate scientist Kimberly Nicholas coauthored a study trying to answer this question: What are the most effective changes you can make to your lifestyle if you want to reduce your carbon footprint and help save the planet?

She found that for individuals in high-emitting countries, choices like flying less, driving less, and eating less meat are all helpful. But there’s another lifestyle choice that is much more effective over the long term: having fewer kids.

Yet in her new book, Under the Sky We Make, Nicholas says that if you really want to be a parent, you should go ahead and have kids anyway.

I was happy to read that, because I agree. I’m on the record arguing that having fewer kids will not save the planet — what’s far more important is how soon countries transition away from fossil fuels, and government policy that creates a mass transition to clean energy sources is the big win we need to focus on.

But the idea that it may be wrong to have kids in the era of climate catastrophe is increasingly in vogue. It’s literally in Vogue. And high-profile figures ranging from Alexandria Ocasio-Cortez to Prince Harry to Miley Cyrus have amplified the question of whether childbearing is still morally acceptable.

So I wanted to know how Nicholas reconciles her support for childbearing with her knowledge as a climate scientist. Does she not worry that having a kid will make climate change worse, because adding a kid to the planet means adding another person who will contribute more emissions, plus their kids, their grandkids, and so on? And what about the concern that having a kid now dooms that child to a miserable life on a miserably hot planet? More broadly, how does she think we and future generations can make a life that feels meaningful and worth living, even in an era of climate breakdown?

I discussed these questions with Nicholas, an associate professor of sustainability science at Lund University in Sweden, on the Future Perfect podcast for our Earth Month podcast series. You can listen to the full episode here. A transcript of our conversation, edited for length and clarity, follows.

Can you briefly explain what your study determined about the most useful things individuals can do to reduce their carbon footprint?

Sure. So in that 2017 study, Seth Wynes and I came to a two-part answer. The most urgent and important thing we need to do is cut today’s emissions fast. And what does that is going car-, flight-, and meat-free. Those are the main sources of emissions for high-emitting individuals.

But as you mentioned, there’s a fourth factor that in the long term, over many generations, has an even bigger impact, and that’s the choice to create another child.

How did you measure the impacts?

We did a study of studies. So we assembled a bunch of peer-reviewed studies and carbon calculators. We looked at the full lifecycle. For example, if we’re talking about food, that means farm to fork, the whole effect along the whole chain that your choices make.

And if we’re talking about creating a new person, that means not only the decision to make a new child and the emissions that will entail under today’s rates, but also the likelihood that that child will go on to have children of their own and carried forward many generations. That’s one reason that number was so big and that in the long term, over many generations, [childbearing] has the biggest impact.

What I think is really interesting is that despite you and your colleague being the ones who ran this study that produced this finding, you still say that people should totally have kids if they really want to be parents. So how do you square that circle?

One thing it’s really important to realize is that population is actually irrelevant to solving the climate crisis. And the reason for that is that we only have the next few years to solve the climate crisis reasonably well.

We know that we have this limited carbon budget that determines how much warming we’re going to experience. We’re really close to scary and dangerous limits right now. And we know what we have to do, which is leave fossil fuels in the ground and switch to regenerative and sustainable agriculture. That’s what our job is basically in this next decade.

So in that sense, creating new people? Well, yes, of course, it is true that more people will consume more resources and cause more greenhouse gas emissions. But that’s not really the relevant timeframe for actually stabilizing the climate, given that we have this decade to cut emissions in half.

The nonprofit Founders Pledge put out a report last year saying it’s just not true that having fewer kids is the best way to help the climate. It says that the problem with most studies is that they don’t account for future changes in government policy — that climate policy will almost definitely get way stricter over the course of our kids’ and grandchildren’s lifetimes, and that will constrain the amount of carbon they will be able to emit.

So they say that it doesn’t make sense to run this sort of calculation where you’re counting my emissions, my kids’ emissions, my grandkids’ emissions based on historical rates. What do you think of that argument?

I think some of it is fair. [Our study] made some assumptions, one of which was, as you mentioned, if emissions from each new person stay the same as they are today. I would push back a little and say, I don’t think we can treat it as inevitable that that’s not the case. Right now, governments are reducing emissions 10 times too slowly to meet our Paris agreement goals. We are not doing nearly enough and we are really in danger of completely missing those goals.

But as I said, reducing population is not the way that we’re going to solve the climate crisis.

The evidence shows that when women are given opportunities in society — when education and equality are increased — women tend to choose to have smaller families and that has a side benefit of reducing climate pollution. But I’m not saying we should educate girls and empower women as a climate strategy. We should have a world where women and girls are equal and have opportunities because that’s the kind of world we want to live in.

This discourse about climate and population growth and educating girls often gets really tricky, right? Because sometimes people can use it to argue for population control. And some big mainstream climate groups in the US like Project Drawdown, for example, do talk a lot about the importance of educating girls and getting them access to family planning services. But since most rich countries like the US already have super low birthrates, that argument seems like it would disproportionately affect people of color in the developing world. Is that unfair, given that rich countries are the ones who created the climate crisis?

Yes, there’s so much that is unfair about the climate crisis. I think there is a really ugly history with the discussion of population. And it is a very sensitive and personal issue, and there are so many ways that it can go wrong. I think that’s why, for example, Project Drawdown puts educating girls in the category of improving society. It’s different than solar panels or electric cars. It’s like, this is something that we need to do for you to live in a better world and to meet other sustainable development goals. And it will likely have a side benefit for the climate. But it’s not really the right way to think about it as a climate strategy.

To put it another way: This is not the case, but if for some reason educating girls caused climate pollution to go up, it would still be the right thing to do and we would need to cut that climate pollution in another way.

I’m curious if you worry that telling people to focus on their individual lifestyle choices, like not flying or not having an extra kid, maybe distracts us from the bigger systemic changes we need to be making. Maybe we should be focusing our energy and attention on fighting for the big win — a mass transition to clean energy sources, which would come through changes in government policy.

I’m not worried about this being a distraction, because it is actually important and necessary, and I think it’s a problem if it gets trivialized. Consumers or households are actually a little over 70 percent of total greenhouse gas pollution. You can look at [the same data] another way and say that fossil fuel companies are [responsible for] over 70 percent. Both of those statistics are correct. It depends if you attribute responsibility to the production or the consumption of fossil fuels. We have to stop both the production and the consumption of fossil fuels.

I want to talk about the other big question that some people might be worrying about, which is, is it wrong to have kids now knowing that you’re dooming them to a pretty bleak future? When people raise that concern with you, what do you say?

This is a conversation I’m having more and more. I can provide some context and information on what climate predictions look like, but people have to go within themselves and look at their own priorities and values. For example, what does it mean to have a meaningful life? What would be necessary for yourself and a future child to have a meaningful life?

You mentioned in your book the example of a friend who took a weekend out in nature by herself, let her mind get really quiet, and then asked herself simply, “Do you want to be a mother?” And the answer that sprung up in her mind was a resounding “Yes!”— that felt like a core part, an essential part of what would make her life feel meaningful and would make the story of her life make sense to her. In the book you say that in that case she should go for it.

Absolutely. That is my view on how I would like people to approach this decision. For my friend Michelle, as you mentioned, she had this really powerful experience where she did feel really drawn to becoming a mother and was able to choose that path. So I think for folks who have that feeling — as a friend put it, “a child-shaped hole in my heart” — yes, those are people who want to and should become parents.

This isn’t the first time in history that a generation has had to ask whether having kids is wise or morally acceptable. Lots of people were asking themselves the same questions during the Cold War, when the fear of nuclear annihilation was at a fever pitch. A lot of Black people in the US have had to ask it, too, having worries about bringing kids into a violently racist system. And my dad actually told me that when he was my age and living in Jerusalem, he and his friends used to worry that maybe it was immoral to have kids because what if the radiation from Chernobyl reached them!

I wonder how we should think about this. On the one hand, we truly are at this unique moment in history. On the other hand, people often seem to feel that way. So maybe that shouldn’t stand in our way.

That’s a great point. Those who have to make the choice [to have children] even in very difficult situations, sometimes will make it. I have dear friends, one of whom was diagnosed with terminal cancer and died at 37. He and his wife Lucy decided to go ahead and have a child even knowing that he was dying.

One conversation that they had was, well, will this make it harder to leave a child behind? And my friend’s response was, “Wouldn’t that be great if it did? Like, wouldn’t it be great if I have this experience that is so beautiful and wonderful and meaningful and lovely and it does make it harder to leave because I have more to say goodbye to — but I did get to have that experience.”

For him, having this experience was really meaningful and important. And even knowing that he himself would not be there for much of her life, it was still a decision that they went into jointly and freely. So I think people make meaning even under really dire situations.

Let’s talk a bit about the role of the priors we each bring to this meaning-making — culturally, religiously. I’ll tell you a little story. I grew up in the Jewish community, and when I was a kid, I learned a story about when the Israelites were slaves in Egypt. The Israelite men didn’t want to sleep with their wives because they didn’t want to bring kids into the world only to see them become slaves to Pharaoh. But the women disagreed with this logic. They believed that somehow things would get better and someone would save them. So they seduced their husbands. And lo and behold, nine months later, Moses was born and he ended up freeing the Israelites from slavery.

This story made a huge impression on me when I was young. And it is part of why, for me personally, I choose to say yes to kids, as an expression of hope and a vote of confidence that we can make the world better. Do you see people often being guided by priors like that, and to what extent should we let ourselves be guided by them?

That’s a beautiful story. Yes, humans make meaning from stories and traditions, and that is a really important guide to how we make our big life decisions. So I think that does have a really big and important role to play. Although I think in the case of climate change, we should not be planning for somebody else to save us. We actually have to save ourselves.