Prove your humanity

Michael E. Mann is one of the most well-known climate scientists on the planet.

From the famous hockey stick curve graph, showing how dramatically our fossil fuel use has warmed the earth, to his many awards, including his election to the U.S. National Academy of Sciences, and his media appearances, Mann has become a leading voice in communicating the science behind the climate crisis and its solutions.

It’s fitting then that his most recent book goes all the way back to the beginning, into our planet’s deep paleoclimate record, to unearth lessons about where we’ve been and where we are going. The Allegheny Front’s Kara Holsopple recently spoke with Mann about “Our Fragile Moment: How Lessons from Earth’s Past Can Help Us Survive the Climate Crisis.”

Mann is a Presidential Distinguished Professor and Director of Penn Center for Science, Sustainability and the Media at the University of Pennsylvania.

LISTEN to their conversation

Kara Holsopple: You write that right now we’re living on this Goldilocks planet: It’s not too hot, it’s not too cold. It’s just right for us humans. But as the title suggests, this is a fragile moment when all of that could change. How close are we to changing the planet into an inhospitable place for us? 

Michael Mann: The global climate was remarkably stable for 6,000 years prior to the Industrial Revolution. We built this massive societal infrastructure, and it’s dependent on the stability of that climate.

What we’re doing now is rapidly warming the planet and leaving that fairly small envelope of variability that existed in the past. That’s what makes this moment so fragile. If we continue on the course that we’re on, ultimately, we will exceed our adaptive capacity as a civilization and as a species, frankly.

So, this is a critical juncture. It’s not too late to take the actions necessary to preserve our fragile moment. But if we don’t take those actions in the near term, then it will give way to something much less hospitable.

Kara Holsopple: The Gaia hypothesis from the 1970s suggests that earth systems regulate conditions on the planet and make the climate resilient, up to a point. How has this hypothesis been used by environmentalists and climate deniers over the years? 

Michael Mann: It’s sort of ironic. The Gaia hypothesis was put forward by the iconoclastic scientist James Lovelock and the great scientist Lynn Margulis back in the early 1970s.

It basically holds that there are sort of restoring mechanisms in the Earth’s system, and they include the behavior of life itself, that help keep the planet within habitable bounds. It’s almost like it’s a sentient creature regulating its environment to preserve life. But that’s not what it’s doing. You can see how it could be taken out of context in any number of ways. 

Environmentalists liked the sort of Earth mother, Earth goddess framing, especially in the early 1970s. It was part of the ethos of that time.

But at the same time, this idea that the system is stable could be hijacked by special interests, by polluters to say, “Oh, well, you know, this system has these restoring mechanisms so we can basically do whatever we want and it’ll just fix itself.”  Of course, that’s a distortion. That’s not what Lovelock and Margulis were arguing.

When you look at Earth’s history over billions of years, you can see examples of giant mechanisms that have helped keep the planet within habitable bounds. But there are exceptions. There are some profound exceptions in the past where life actually almost caused and, frankly, did cause the climate to sort of spin out of control.

Of course, today, we are in a position where we could do that if we continue adding insult to injury with carbon pollution and all the other detrimental impacts on the environment associated with human activity. 

Kara Holsopple: The book looks at several time periods in the paleoclimate record. For you, which event in this deep history holds the most salient lesson for us now about our own moment of climate crisis and how we get out of it?

Michael Mann: It’s tough to choose. One that I focus on in some detail is a major extinction event. It’s probably the most famous: It’s the one that killed off the dinosaurs, or at least as we like to say, the non-avian dinosaurs, because birds are actually dinosaurs. We see dinosaurs every day.

The dinosaurs didn’t know what was coming, and they couldn’t do anything about it. We don’t have that excuse. 

But every dinosaur larger than a dog basically perished in this event. It was an asteroid impact 65 million years ago. It ejected all of this debris into the atmosphere, blocking out the sun and leading to a fairly dramatic cooling, which basically caused the extinction of any creatures that couldn’t burrow down into the ground or underneath the ocean to shield themselves from that cooling.

There’s a lesson there, which is that one species’ extinction can be another species’ boon. When the dinosaurs perished, they left some niches to be filled by the very small mammals that were scurrying around behind the rocks at the time. They are our ancestors. We wouldn’t have emerged; the mammals wouldn’t have taken over if not for the extinction of the dinosaurs. The dinosaurs didn’t know what was coming, and they couldn’t do anything about it. We don’t have that excuse. 

Kara Holsopple: Right. You write that we’re not dinosaurs, and that’s good news. Along those lines, you also write that climate denial is no longer the biggest obstacle to solving the climate crisis. It’s doom. Can you talk a little bit about that and what you mean? 

Michael Mann: It’s no longer credible to deny that climate change is happening because we all see it. Polluters can no longer claim it’s not happening, but they still want to keep us addicted to fossil fuels, so they’ve turned to other tactics.

My last book, “The New Climate War,” was really about that, and one of those tactics, ironically, is doom-mongering. It sounds odd, right? But if you really come to believe that there’s nothing that you can do, that you have no agency, then it potentially leads you down that same path of disengagement as outright denial.

They’re bad actors who have fanned the flames of doom-ism because they know it will lead many of those who would otherwise be on the front lines — environmental activists, progressives, people who really care about the environment — if you can deactivate them, then as a polluter, that’s a major win. 

If you really come to believe that there’s nothing that you can do, that you have no agency, then it potentially leads you down that same path of disengagement as outright denial.

We’ve seen claims by some players in this space that we’ve warmed the planet enough that we’re releasing massive amounts of methane from the permafrost, and it’s a runaway process, and we can’t stop it no matter what we do. We’ve set off this time bomb. We’re all going to go extinct. We might as well just enjoy the ride, I suppose. And that’s not true.

There’s no evidence that that’s happening with methane right now. Sometimes, I’ve seen them weaponize the paleoclimate record for that very narrative. That’s part of what got me interested in writing this book.

If you look at an event called the PETM, which stands for the Paleocene-Eocene thermal maximum, it was a rapid warming event, and the doomers will say, “Oh, and it was runaway methane-driven warming, and it caused all these extinctions just like it’s going to cause our extinction.” And that’s not true.

If you warm up the ocean bottom, you can release some of the methane that was stored there, and that can increase the warming. But it’s a modest positive feedback — it adds a little bit of the warming, maybe 10%. The bulk of the warming, 90% of the warming of the PETM — the bulk of it was carbon dioxide, not carbon dioxide from fossil fuel burning, but natural carbon dioxide from volcanic outgassing.

There was an unusually intense sort of episode of volcanic activity that pumped carbon into the atmosphere about a hundred times slower than today. So, we point to the PETM as an example of one of the most rapid climate change events we can find in the geological past. But even that is slow compared to today.

The lesson there is we are warming the planet faster, and that’s an even greater threat. But it’s not cause for doom. The thing that caused the warming was the carbon dioxide. And we can stop warming the planet with carbon dioxide by stopping the burning of fossil fuels.

Kara Holsopple: Why do you think there’s still a lack of urgency among politicians and even people in the general public to take that agency and act on climate change? And how do we fix that? 

Michael Mann: Ultimately, there’s been a lot of misinformation. I would call it disinformation. It’s not just that they got it wrong. They’re intentionally communicating misleading claims and untruths about climate change — polluters, conservative media outlets, and conservative politicians who see themselves largely as advocates for the very powerful and wealthy fossil fuel industry. It is why the public is as divided as they are.

The scientific community has uniformly said that climate change is real. It’s caused by human activity, particularly the burning of fossil fuels. And it’s having these negative consequences. There’s no there’s no question about that within the scientific community.

And yet, when you look at the public, there’s a substantial fraction, not so many, who are hardcore climate deniers. The polling suggests they only number about 10%. They have a much greater voice because of the sort of megaphone of the conservative media, social media, bot armies, and trolls that would make you think that there’s a very large proportion of the American public that are hardcore deniers.

But there is a wide, much larger, probably 40 to 50% of the confused middle. They think there’s some sort of debate. They’re not convinced it’s really that much of a crisis, or maybe we can’t really do anything about it anyway.

They’ve got all of these other kitchen table problems to worry about in the meantime. And this seems so abstract. But it is becoming less abstract because the rubber’s hitting the road now, and I think that is changing the equation. I think we are seeing a shift because of that.

Michael E.Mann is Presidential Distinguished Professor of Earth & Environmental Science at the University of Pennsylvania with a secondary appointment in the Annenberg School for Communication. He is also the director of the Penn Center for Science, Sustainability and the Media.

Mann is a member of the U.S. National Academy of Sciences and the author of several books, including the recent “Our Fragile Moment: How Lessons from Earth’s Past Can Help Us Survive the Climate Crisis,” published by PublicAffairs, an imprint of Hachette Book Group, Inc.