Is having babies bad for the planet? Here’s the link between population and climate change

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Editor’s note: This is the third in a series of columns by Joana Tavares, The Tribune’s American Association for the Advancement of Science mass media fellow, answering reader questions about climate change. Tavares is completing a doctorate degree in earth sciences at UC Irvine.

“No one ever talks about the relationship of the world population and climate change, which the two really go hand in hand. The world population is nearing 8 billion now and no matter how much we try to not leave a carbon footprint just existing in this world adds to climate change with needing food, water, heating and things of the sort. (... )People don’t seem to be concerned about having large families, but it affects us all when people are still having four or five kids. Just a thought.”

— Laurie, San Luis Obispo

Dear Laurie,

A few days ago, one of my best friends, Mary, called me to share exciting news: She is pregnant with her third child. As a climate conscious person, can I be happy for Mary?

In other words, how many children are too many when it comes to a family, a country or a planet?

Although it may seem like “no one ever talks about the relationship of the world population and climate change,” I can assure you that climate scientists and activists­­ talk quite a lot about that link.

However, we don’t often air this discussion in the public sphere.

The most poignant reason why experts may be wary to talk publicly about this is the fact that the topic has been repeatedly co-opted as part of racist, xenophobic, and misogynistic narratives used to justify coercive, and unjust policies or criminal activities throughout history.

And then there is the fact that, despite what certain authors have said in the past, we have no scientific consensus on the role human population plays when it comes to climate change.

As a species we are over-utilizing natural resources, driving other species to extinction, and even changing the planet’s climate with our pollution. But is that a direct consequence of the increasing number of people on Earth? Or are these trends symptoms of a bigger problem?

How many people can the Earth sustain?

Nobody knows what the optimum number of humans on Earth is.

We know that humans are consuming natural resources 1.75 times faster than what our planet’s ecosystems can regenerate, so clearly above Earth’s carrying capacity. However, that may be because certain groups of people have been utilizing more resources than others.

Scientists have calculated how many Earths would be needed if everyone on the planet lived like the residents of certain countries. We’d need 5.1 Earths if everyone lived like Americans, or 3.0 Earths if we lived like Germans, but only 0.8 Earths if we lived like Indians or 0.5 Earths if we lived like Angolans.

You may be thinking, “Clearly, we want everyone to live safely, comfortably, and more like the people in developed countries, so we should somehow reduce global population and ensure better distribution of wealth.”

But could we, operating within current political-economic systems, sustain the high standards of living achieved by wealthy people in developed nations without the exploitation of cheap labor and deficient environmental regulations in developing countries? Probably not.

Our current systems make low-cost imports of natural resources and products from those poorer nations possible, which benefits the folks at the top of the food chain.

The reality is that if we want to protect the environment and make the world a better place for all, we will need to reconsider much more than the number of humans on earth.

Is my friend harming the planet by having another child?

Mary is a white, college-educated American with a middle-class income. So is my friend harming the planet by having a third child?

It depends on how you look.

Is Mary any guiltier of planetary destruction than Beyoncé or Bill Gates, who each have three children of their own? Should she be shamed for fulfilling her dream of having children, while Elon Musk, the richest person in the world, has seven kids?

The fact is, the environmental impact disparity between the wealthy and the poor that exists among different countries, also exists in the United States.

In the U.S., people in the top 10% of the income pyramid produce 7.3 times the annual emissions generated by their fellow citizens in the bottom 50%.

In Europe, the 10% richest people produce six times more emissions than those in the bottom half; those in East Asia produce 13 times more emissions.

If we keep working our way up the privilege ladder, there are fewer and fewer people left to blame. Perhaps it is time we start looking at the problem from a different angle.

What’s the benefit of voluntary family planning?

In the distant past, having lots of children meant a greater chance of success for our tribes. It meant more hands to hunt and gather, and later, to work in the fields and factories, as well as more people to fight in wars, and greater group resilience during pandemics or natural disasters.

Sometimes, children and women were sold as commodities, as slaves or in exchange for dowries, revolting practices that persists to this day in some places.

Having babies was a cause of celebration for some, while others saw it as an inevitable consequence of being a woman in a world in which you had little or no agency over your own body.

Over the past century, the mechanization of production at all levels, and developments in modern medicine, sanitation, nutrition, transportation and communication have revolutionized the way humans live.

As a result, fewer babies and children die, old people live longer, and global population growth is now exponential.

In 1900, there were two billion people living on Earth, and life expectancy was 31.5 years. Now there are almost eight billion, and life expectancy is 73 years.

Something else also started to change: many people now had access to more options on how to live their lives.

For women in particular, that meant having more agency over their own lives, having reproductive rights, and consequently, liberation from pre-established roles in society.

We see the results from the empowerment of women reflected in demographics data from several countries, and globally as well.

In the 1950s, the average Earth family had five children. Now they have less than three.

While the absolute value of global population is still increasing, the rate of that increase is slowing down, and experts predict it will level off by 2100.

Let women choose

Research by the Drawdown Project and others confirms that investing in women’s education and protecting their rights, including their reproductive rights, have long-lasting benefits that lead to reductions in greenhouse gas emissions.

That, combined with other actions to replace fossil fuels with alternative sources of electricity, plus adjustments to the way we build, farm, consume, and eat would allow us to cut 50% of our emissions by 2030, achieve net zero by 2050, and avert the worst consequences of climate change. But if we want these solutions to take root, we will also need to face the failures of globalization, fix systems that are not working, and protect women’s rights everywhere in the world.

Some people, like my friend Mary, want to have three, four or more children. I am absolutely thrilled for her.

I have other friends who chose to have no children at all. They want to focus on other aspects of life. I am absolutely thrilled for them as well.

I always knew that I wanted to have one child only and have greatly benefited from modern healthcare and reproductive rights to live a fulfilling life according to my choices.

I can only wish the same level of dignity and respect for every person on this planet, for their own sake and for the sake of our shared future on this blue marble we call home.

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