Record heat, a climate reckoning: How will humans respond?

USA Today

2 days ago

On a special episode (first released on June 25, 2025) of The Excerpt podcast: As the earth continues to warm, how will mankind respond? Is it in our nature to act? Author and climate scientist Kate Marvel joins USA TODAY's The Excerpt to discuss her new book 'Human Nature,' which explores how emotions may be key to our survival.
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Hit play on the player below to hear the podcast and follow along with the transcript beneath it. This transcript was automatically generated, and then edited for clarity in its current form. There may be some differences between the audio and the text.
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Dana Taylor:
Hello, I'm Dana Taylor, and this is a special episode of The Excerpt. Climate change, global warming, we've all heard this steady drumbeat of doom. But a recent five-year forecast by the World Meteorological Organization and the UK Meteorological Office puts it starkly. The world will likely soon break another annual temperature record, and according to The Associated Press, the heat will be deadly. What would happen if we embrace the idea that the future still rests firmly in our hands? Is it in our nature to learn, adapt, and change? And equally important, is there still time? Author and climate scientist Kate Marvel dives into those questions in her new book, Human Nature, on bookshelves now. Thanks for joining me, Kate.
Kate Marvel:
Oh, thank you so much for having me.
Dana Taylor:
In your work, you manipulate climate models to gauge the impacts of climate change. In the simplest terms, can you briefly walk us through the creation of one of these models and how you've used them to glean data?
Kate Marvel:
So a climate model is basically a toy planet on a computer that we can do experiments on that would be impossible or unethical to do in the real world. We can't gauge human influence on the climate by asking everybody to go live on another planet for a couple of hundred years, but we can do that in the safe digital confines of a climate model. Now, what a climate model is is basically the encapsulation of everything we know about the physics and chemistry of how the world works, written down in equations and then translated to code.
Dana Taylor:
The most startling moments I experienced while reading your book are when you were expressing your anger regarding gaslighting by climate change deniers. Was there a specific tipping point for you here? And how did you grapple with how you would express anger in your writing?
Kate Marvel:
Yeah. I mean, I struggled a lot with expressing anger. I actually struggled a lot with expressing any emotions. Because scientists, we're supposed to be neutral, we're supposed to be objective, we're supposed to have no feelings whatsoever. And I was worried that if I expressed anger or if I expressed fear or grief or even hope, I would be taken less seriously as a scientist or maybe my science would be seen as a little bit less credible. But then I realized that we don't make ourselves more credible when we lie about not having feelings. I am a scientist, but I'm also a human being and I'm a human being who lives on this planet. And that means I feel things when I study the planet that I live on and that everybody I love lives on.
So yeah, rage. I do feel incredible anger when I think about the history of climate science. None of this stuff is new. We've known about the greenhouse effect for more than 100 years and the history of climate science, scientists finding things out, is intertwined with the history of people pushing back on this and lying about it. So you can't really look at the history of climate science without looking at the counterbalancing history of climate denial. And I'm really mad about that.
Dana Taylor:
In your book you wrote that, "Weather is what we humans experience over our short lives and that climate is a matter for the Gods." What did you mean by that? And are you worried that some readers will walk away thinking there really isn't much that humans can do at this point?
Kate Marvel:
I wrote that because I wanted to include it in the context of, I talk about climate models in the context of Greek mythology, especially the myth of Cassandra, who famously was cursed to be able to see the future, but nobody would believe her. And so oftentimes climate scientists are called Cassandra's because we're making these projections about dire futures, but it seems like nobody's listening to us. So that was the context of things that I was playing with a little bit where I really wanted to bring that in. I think my colleague Dr. Marshall Shepherd at the University of Georgia puts it excellently that weather is your mood and climate is your personality. So climate is essentially the background conditions under which all weather can occur. It's not supposed to change this fast, but human beings, because we have changed the chemical composition of the atmosphere, are indeed changing the climate.
But when I look at it, I think, wow, wouldn't it be scarier if we didn't understand what was causing climate change? Wouldn't it be scarier if this were some meteor heading toward us that we didn't know how to stop? But the fact that we understand exactly what is causing climate change, it's humans doing things that emit greenhouse gases into the atmosphere, that means we know exactly how to stop it. So I think it's really important for scientists to stress that there are things that we can do. We are not doomed to inevitable, catastrophic climate change. We can still avoid the worst impacts.
Dana Taylor:
I want to stick with that in talking about the weather. You also said that all weather is formed in a changing climate. Can you help us understand the weather through the eyes of a climate scientist?
Kate Marvel:
There is no weather now that's not happening against the backdrop, like you pointed out, of this changed climate. So I cannot tell you what the weather is going to be like in New York City where I live 10 years from now on June 1st. But what I can tell you is that it's likely to be warm. I can tell you some of the basic contours of what it's likely to be because I know that New York City is on the East Coast of a large landmass. I know what the prevailing winds look like. I know the factors that shape the climate of New York City.
Dana Taylor:
Clearly humans, Homo sapiens, have adapted to life on this planet for roughly 300,000 years. Is it correct to say that based on your climate models, mankind will not be able to adapt quickly enough?
Kate Marvel:
I don't know because people are very, very, very difficult to put in a climate model. I am a physicist, I know exactly what water droplets and air molecules are going to do because those things obey the laws of physics. You push them, they always move in exactly the same way. Human beings are much more difficult to predict. So what human beings are going to do in response to the changing climate, are we going to take sensible science-based decisions and mitigate the change climate and adapt to the changes that have already occurred? That's a possibility. But are we going to panic and blame each other and have scapegoats? That's also a possibility. So I have learned as a physicist to actually be very, very humble about what I don't know. And the thing that I really don't know is what human beings are going to do.
Dana Taylor:
Well, the warning in your book that climate change is unlikely to dole out one disaster at a time is something that really struck me. I want you to help us understand what you call the misery index. Have humans survived worse than what we're experiencing now or worse than what your models predict we will experience in the near future?
Kate Marvel:
So one of the scariest things about climate change is that obviously it increases the risk of heat waves. But at the same time, it changes the humidity of the atmosphere. And I think we've all experienced it, that dry heat is very different from humid heat. A lot of people say, "It's not the heat, it's the humidity." And there is actually a threshold, what we call the wet bulb temperature, which is basically a measure of the combined heat and humidity. There's a point where that exceeds a value so that the human body cannot cool itself off by its natural response, which is sweating.
And when the wet bulb temperature, that index, exceeds this particular critical threshold, if you go outside, even if you're young, even if you're healthy, even if you're not moving around very much, you will die. Now, that's not happening with any regularity right now, but we have seen in a couple isolated cases that threshold being exceeded. And for me, that's something that's very frightening because that is a little glimpse of possibly a world, particularly in the tropics, particularly in the Global South, where human beings are essentially no longer welcome.
Dana Taylor:
What would a reverse Ice Age look like? And are we at risk?
Kate Marvel:
Let's think about what the Ice Age was. Ice Ages are caused by little tiny wobbles in the Earth's orbit as it goes around the sun. The last Ice Age was around 21,000 years ago, scientists call it the last glacial maximum. And during the last glacial maximum, the temperature was between five and six degrees Celsius colder than it was now. And just to put that in perspective, what we could be looking at under an absolute worst case scenario is warming of about five to six degrees Celsius by the end of the century. So when you think about it, when you think about the difference between now and the last Ice Age, the planet looks very, very, very different back then. Human beings are surviving, there are species that are surviving, but it is a completely foreign planet to us. And when you look forward into the future, if it does warm by five degrees, six degrees Celsius, that is a planet that is also completely alien to us, completely foreign to us. And that could be the planet that we're sending our children to go live on.
Dana Taylor:
You wrote that you grew up wanting to make bad movies. Do you feel like a scientist in a bad movie? And what can that scientist do to save the day?
Kate Marvel:
I often feel like a scientist in a bad movie. And what makes a movie a disaster movie is usually when the scientist gets ignored. So I think it is very important that we not be ignored. The problem that I have with bad movies and good movies too, is that they tell the story of a single person. Movies usually have a hero. And that is not what's going to happen with climate change. There is no single hero. There's no one person who's going to come along and save all of us. We are all going to have to work together. We are all going to have to do this ourselves.
And for me, that's almost comforting. It means that I don't have to be the star, I don't have to carry this picture on my shoulders because I am not capable of doing that. But it's knowing that I am in this with essentially all of humanity. And as a result, there are so many heroes of this story. There's so many people working on various aspects of this enormous problem to do something that humanity has never done before. And for me, that's what happens in a good story, is people do something that they didn't think they could do.
Dana Taylor:
Finally, you lean into human emotions like fear, guilt, and wonder. What do you hope readers might better understand about human civilization and climate change after reading your book?
Kate Marvel:
I hope they see themselves somewhere in the book. I hope they understand that climate change is important, not because it's affecting a planet necessarily, but because it's affecting our planet. I get really annoyed when I see these headlines that say, "Scientists concerned about climate change, or "Scientists worried about melting glaciers." Because I think, honestly, where do the rest of you live? What planet is everybody else on? And I want to make it very clear that scientists care about this because we're human beings and all human beings should care about this. This is not a scientific problem, it's not something that only scientists should be worried about, and it's certainly not something that all scientists can solve. And so I think that if we want to address the magnitude of this problem, one of the best ways to get started is to talk about it, to talk about it to ourselves, to talk about it with each other. And what I really hope is that people read this book and come away thinking, hey, I see myself in this picture. That to me will make it a success.
Dana Taylor:
Human Nature is available on bookshelves now. Thanks so much for being on The Excerpt, Kate.
Kate Marvel:
Oh, thank you so much. It was lovely.
Dana Taylor:
Thanks to our senior producers, Shannon Rae Green and Kaely Monahan for their production assistance. Our executive producer is Laura Beatty. Let us know what you think of this episode by sending a note to [e-mail]. Thanks for listening. I'm Dana Taylor. Taylor Wilson will be back tomorrow morning with another episode of The Excerpt.