Peter Brannen is the award-winning science journalist and deep time aficionado behind the book, The Ends of the World. On this bonus episode of Reversing Climate Change, he comes back on the show to discuss his recently published articles in The Atlantic, ‘The Anthropocene is a Joke’ and ‘What Made Me Reconsider the Anthropocene.’ We discuss why deep time is such a foreign concept to the general public and Peter explains how the term Anthropocene has evolved to encompass all human activity.
Full Transcript
Ross Kenyon: Hello and welcome to the Reversing Climate Change Podcast. I’m Ross Kenyon. I’m the lead strategist at NORI. Today I have with me Peter Brannan joining the show once again, RCC alumnus. Peter is a science writer who writes for The Atlantic and other publications and is the author of The Ends of the World, Volcanic Apocalypses, Lethal Oceans, and Our Quest to Understand Earth’s Past Mass Extinctions. Great book. One of my favorite geology books that I’ve read. I’m actually due for another read-through of it, Peter.
How often do people tell you that they’re going to read your book twice? Does that make you smile? Yeah, I’ve heard that a couple times. And it’s great that people are getting as much out of it as it seems like they are. There’s a lot to it. And wrapping your head around anything deep time, I think you really need to be patient and sink into it. Is that your experience too? Because it’s very foreign to me.
Peter Brannen: Yeah, it’s sort of like this entire landscape of history that is infinitely longer than human history that is, I think, not plumbed as much as it could be by sort of the popular press because so much incredible stuff has happened on the planet. I think part of the hurdle to that is that a lot of it is hidden away in academic papers written in the language of geology. So it’s hard to sort of crack. But once you sort of understand what you’re reading, there’s yeah, there’s just so much incredible stuff in the fossil record that it’s fun to be able to write about it.
Ross Kenyon: Indeed. So if you are interested in this topic, you can go back and listen to Peter’s first episode. There’s a link to it in the show notes. But otherwise, you don’t need to understand this episode. Today, we’re talking about the Anthropocene or Anthropocene. I’ve heard both. Peter, I’m not sure what to do with that. I’m sure there’s going to be partisans for each pronunciation, but we’re just going to roll with it. You’ve written a couple articles, though, at The Atlantic about this concept.
So we’re going to dive into this because your mind has, well, maybe I shouldn’t say it that way. You’ve been debating whether or not the Anthropocene is a useful concept for understanding our present moment, our geological moment. And then there’s been some reactions against this too. But maybe the best place to start is What in common understanding is the Anthropocene? What do people mean when they use it?
Peter Brannen: Well, I think it’s sort of escaped its geological confines. And there’s now this colloquial use of the Anthropocene, which is basically like anything that humans do. And I’ve even heard people use terms like the capitalocene, referring to capitalism. And, you know, as someone who writes a lot about geology, I just felt like Some of the conversation had completely escaped the sort of stratigraphic basis, you know, what sort of fossil record humans would actually leave behind and was just sort of this catch-all term for human activity. And in that sense, I didn’t really...
You know, I guess it’s useful to have a word that encompasses all the ways humans are changing the planet right now. But I thought it was also sort of an opportunity to sort of introduce people to how the fossil record works and sort of the scale of deep time. Because as I point out a lot in my first piece, you know, I think some people have this idea that if you like dig into the earth, there’s a dinosaur layer and there’s a woolly mammoth layer. And now there’s going to be a human layer that’s going to be just as substantial as those previous periods in earth history.
From a deep time perspective, we have, you know, being as generous as you can to human civilization, it basically doesn’t exist from a geological perspective. The late Cretaceous, I use for example, was 46 million years long. That’s an epic. And there’s, you know, people who would argue that the Anthropocene is also an epic, and it started in the Truman administration. So the timescales are just... With nuclear energy and the nuclear bomb... Yeah, yeah. So there’s, you might see this layer with this weird spike in radioisotopes that marks when we started using the Trinity test at the end of World War II.
And that would sort of be this stratigraphic marker for the Anthropocene. I point out in the piece that a lot of those radioisotopes would decay, you know, in deep geological time. So you wouldn’t actually see that. But And most of the geological record we have is from the ocean, not from land. So the best chances of seeing human impacts in the far future would be sediments at the bottom of the ocean. And, you know, if you study past periods in earth history, you can be in a canyon and just see, you know, mile thick deposits that represent tens of millions of years, but represent one epic.
And at that scale, you know, humans might, there might Be an acidification event with the CO2 we’re putting into the air and you might get a little dissolved clay layer. But then, you know, in a few tens of thousands, hundreds of thousands of years, you’d start getting normal carbonates again. But the Anthropocene would just be this little line in the rocks, which is really, you know, unprecedented in Earth history to call weird lines in the rocks, their own epics. And I compare what we’re doing now to these Sort of convulsions in the Earth system and deep in the geological past, of which there are a lot when the Earth all on its own through volcanic activity and other, you know, cataclysms injects tonnes and tonnes of CO2 into the air, gets really warm, you get acidification, you get mass extinction, you get ocean anoxia, all the stuff that we’re doing and threatened to do in the next few centuries.
And a lot of these are mass extinctions, which I talk about in my book. But then, you know, the Earth recovers because we’re talking about geological time. So in a million years, things sort of Start recovering and then you get big layers of rocks again. But the weird little lines are considered events. They’re not considered epics all on their own. So I argue in the Atlantic piece that given that some of these events in our history happen over hundreds of thousands of years and actually are more extreme than what we’ve done so far and aren’t considered epics, some happen in the middle of epics, weirdly enough, that what we’ve done is Although it’s been really disruptive, and I’m not downplaying humans' effects environmentally, which have been basically a catastrophe, we have not earned a geological epoch yet.
And to say that we’re in a new epoch, I argue, is really optimistic because it implies that we’re actually going to persist into geological time and figure out a way to live in balance with this planet enough that we could actually persist into something like geological time. But we haven’t earned that yet. We just showed up, you know, two to three hundred thousand years ago, and civilization’s just a few years. Millennia old, and given the way things are going right now, it’s really wildly optimistic to think that we would, you know, have lasted as long as the late Cretaceous, which was thousands of times longer than the existence of human beings.
So that’s basically the argument I put forward in the first essay I
Ross Kenyon: wrote. Yeah, there’s so much there. Yeah, sorry. No, no, that’s okay. We talked about this a lot. If you’re interested in this topic, you should also listen to the David Grinspoon episode we’ve done. And David also gets a mention in your article, Peter. But people who, let me read this back to you and you can tell me to what degree I’m correct or not. But the Anthropocene is posed as having begun when humans became a force capable of changing planetary systems on their own.
So sometimes people attribute this to agriculture and large scale land use changes and stuff like that. Others attribute it to internal combustion becoming a thing or maybe even coal. And then also there is nuclear. That’s another landmark event that people pose as the beginning of the Anthropocene. And this is some new time period in geological time. I don’t know. I mean, because there’s eras, there’s epics, and then there’s events.
Peter Brannen: Is that broadly how it... I mean, event is sort of a casual... I don’t think that’s... It’s not really a... But that’s the smallest, right? Yeah, but there’s not... Things aren’t really divided into... Things are divided into epics that are usually... So this is getting into the second piece, but... The epics are usually broken up by, or at least they can be broken up by, in the worst case scenario, mass extinctions. But usually there’s some change in the stratigraphy between one epic to another.
Yeah, I’ll just leave it there.
Ross Kenyon: Yeah, there’s so many rabbit holes you can go down. But anyways, the biggest though is they end in Zoics, right? So like Cenozoic and Paleozoic and Those are like the longest. And then epics fit within those. And that’s like Cretaceous, Jurassic, etc. And they’re saying that like Jurassic or Cretaceous, we’re having now a new one. It’s called the Anthropocene because we were in the Holocene. And that’s also an epic, right? Yeah. Although, well, there’s also... Or the Pleistocene. Should I back up one further?
Peter Brannen: Well, there’s periods which are bigger than... Epics as well. So there’s like the breakfast of this whole thing, Peter. Oh, no, it’s fine. And a lot of these things like the Mesozoic, Paleozoic and Cenozoic, these are concepts that were, you know, people came up with in the 19th century. So a lot of this stuff is pretty hazily defined. And geology in general, sort of, or a lot of the naming of stratigraphy has this sort of historical aspect to it. And it’s not an exact science.
It’s pretty fuzzy how things get broken up. So they’re Which is something to recommend the Anthropocene because it’s like we’re naming these things. We get to decide what the important units of time are. So why not call this one the Anthropocene? But I’m just comparing it to previous, using the same standards that some of the previous epics have. But you just mentioned the Holocene, which, okay, so for about the last three million years, the planet has been in ice ages, which there’s been something like 50 glaciations where we go in and out of these And then we have these warm interglacial periods for 10,000 years where the ice retreats.
And we’re actually in one of these interglacial periods right now of the larger Pleistocene Ice Age. So the only one of these interglacials that has its own epic is the Holocene, which is kind of anthropocentric. And so that started over 11,000 years ago. But the biggest impact... Biologically, so far that humans have had on the planet and that might be really noticeable in the far future is the extinctions that happened just before and at the end of the last ice age when we wiped out basically most of the large mammals on planet Earth and all sorts of other stuff as we spread into new continents and brought invasive species and hunted and changed the landscapes.
Given that only happened and actually kept going throughout the whole Holocene. So when people showed up in New Islands in the South Pacific, all the big birds and giant snails started going extinct. So there’s been this wave of extinctions that has followed humans all over the planet for over 50,000 years. That again, if you’re in the far future and you’re looking back and you’re trying to decide what’s an epic or not, or what’s a mass extinction even, It would be totally indistinguishable that the extinction of the woolly mammoth happened at even a different time at all, that it wasn’t simultaneous with what we’re doing to the planet today.
It would all sort of be in the error bar of, wow, something really went wrong somewhere near this time period. So the distinction between the Holocene and the Anthropocene doesn’t make a ton of sense to me because it, yeah, things that we’ve really, by unlocking fossil fuels and Changing the planet as radically as we’re doing today is really kind of an order of magnitude, I don’t know, crazier than what we have been doing for the past 200,000 years. But the influence of human beings on the fossil record are on geology.
If that’s where you’re going to find the Anthropocene is, we’ve really been doing that for a very long time.
Ross Kenyon: Okay. So then looking at this from the discipline of geology, maybe this isn’t that useful of a concept if you’re trying to further that discipline. Now you’re saying that Stratigraphy in this way, the defining of strata, like we’ve been going through epics and eras, that sort of left the field of geology in some ways and is now just kind of a public affairs thing. I know people use the Anthropocene or Anthropocene as a way of making a political statement of defining just how large human impacts have become.
So you might Potentially defend its use in like the public sense, but in the specific geological scientific sense, you might reject it or would you still reject both?
Peter Brannen: Uh, no. So I’ve, I don’t know, I guess I’ve softened my view maybe on both because I, I do think getting people to think about these things are important, but you know, I’ll see like an art gallery showing where it’ll be like landscapes of the Anthropocene and it’ll be like just pictures from a city. San Francisco is not going to make it into the geological record. Most of what we do on the planet isn’t going to make it into the geological record. You need incredibly lucky circumstances to leave behind a fossil.
There’s going to be a few cities like New Orleans and Dhaka and Beijing that are in these subsiding sedimentary basins that might get a lot of stuff dumped on them and might Persist for hundreds of millions of years, but the chance that they’d ever come to the surface at any given time in the future and that you’d see them, you know, on the side of a canyon like you would other parts of Earth history are really slim. And a lot of the stratigraphy would be what we’re talking about earlier with like ocean sediment.
So it’s important to get people to think about sort of these global environmental impacts we’re having, but I have softened on the idea that of the geological stratigraphic basis to it too, because as I was saying before, some of these epics and periods in Earth history, The split between them is defined by a big mass extinction or a big crazy event. So in the first piece I say how, oh, you wouldn’t say it’s the asteroidocene when you’re standing next to a T-Rex for the next hour and say we’re in this epic that’s just going to be an hour long basically.
But the asteroid actually did start at the beginning of the Paleocene, which is a new epic. The moment the asteroid hits, you are in a new geological epoch. So in that sense, okay, we haven’t left almost anything stratigraphically that’s going to survive for that long, but humans have probably deflected the course of evolution irreparably in a new direction. Probably not as severely as it happens at the end of some of the other mass extinctions or other periods, but we’ve definitely changed things in a way that is enough to start a new epoch in other parts of earth history.
But I think what I think is strange is that, well, in that case, why are we calling it the Anthropocene? If humans have civilization and they wipe themselves out in a thousand years or even shorter than that, and then there’s no humans anymore, but we forever deflected the course of evolution. And in 10 million years from now, whatever animals are on the planet are doing their own thing. I feel like You know, it’s weird to call that the Anthropocene because there’s the word Anthropo or is the prefix Anthropo, which refers to humans.
So it’s weird to say the age of humans is going to be 10 million years from now when there aren’t any humans just because we deflected the course of evolution. And I think most people understand Anthropocene to be sort of to mean the age of humans. But I’ve, you know, I’ve come around to the idea that, yeah, there’s these events like this one 56 million years ago where you have a big global warming event and it changes the course of mammal evolution and that defines the Boundary between the Paleocene and the Eocene epics.
And we could easily have an effect that profound. So even though that warming event is an event, it does mark the beginning of a new epic. So I think my two essays, one where I say it is the Anthropocene and one where I say it isn’t, are kind of different ways of looking at the same thing. And I feel like I’ve tied myself in knots just talking about it. So I hope any of that is intelligible.
Ross Kenyon: It’s hard talking about this subject because it is very esoteric and challenging as a layperson. It is for me, at least. I always suspect some listeners are like that too. Well, Peter, how bad do we have to be as a species before we can earn our own epic? How much worse were the mass extinctions of the past compared to what’s happening now? Oh, they weren’t much worse. I mean, they were worse.
Peter Brannen: Yeah. In the next century or two, we could actually get to the same level of those mass extinctions. I think just the Anthropocene, the way I always understood it, as I said before, is sort of like the age of humans. So to say that we’re in a new geological epoch, I thought was like, we’re going to persist for geological time. And I think that I’m really rooting for that. And so I think some environmental people took my essay the wrong way to say that, oh, yeah, we weren’t having a big impact.
But it was actually sort of a warning that we are, things are going so poorly for us on this planet, environmentally, that the Anthropocene could just be a blip. And I’m rooting for a long Anthropocene. But to get there, we really need to appreciate just how transient we’ve been so far and just how off the rails things have Because if we don’t get our act together soon, we’re not going to persist in the future on a geological timescale. And so I’m hoping for a long, fruitful Anthropocene because it means that we’ve matured as a species and we’ve learned to appreciate the planet and its sort of operation in a way that’s sustainable on a geological timescale.
And so far, we haven’t proven ourselves as a species yet of that. We’ve been here as a civilization for an absolute And so just yesterday I saw that Rand Paul, of all people, tweeted that it’s very likely that humans are going to live on this planet for hundreds of millions of years into the future. And I guarantee he just does not appreciate what that time scale is like and how short we’ve been here and how off the rails things have gone so far. Maybe he just read some Carl Sagan, David Grinspoon and got real into that.
You don’t know that. I love that message and I love big, bold, ambitious thinking like that. I just feel like some people are counting their chickens before they hatch when they talk about, oh, humans are going to live for millions of years and we’re going to colonize the galaxy and we’re going to spread out and it’s going to go on forever. We need to get our sort of house in order here real quick before we can start wondering how far into geological time. We’re going to go because right now we are mimicking a major mass extinction.
And those are usually really painful intervals that last for a few hundred thousand years. And then it’s not until millions of years afterwards in the aftermath that the planet is really a place you want to be again. So I’m hoping we We are more like one of the long, uneventful intervals of geological history where the sediment just stacks up forever and it’s tens of millions of years long than one of these short, chaotic nightmare periods that leave themselves behind as sort of just weird lines in the rocks.
I’m hoping we’re more like the former than the latter.
Ross Kenyon: Yeah, me too. Well, I hope this was useful for people listening. I think it helps me to understand that maybe for geological purposes, given how if you were looking at The geological record on a canyon wall, the amount of time that humans have been impacting the atmosphere and the environment is so thin that it probably wouldn’t show up. So maybe for geological purposes, maybe it doesn’t qualify as an epic. Maybe it isn’t that useful for academic geology. Maybe this is a useful term to galvanize public action and opinion, or maybe not.
I don’t know. I think it’s an interesting topic. I think you gave us a bunch of interesting ways to conceive of this and to work through it. I’m not really sure what I think about it now. The more I talk about it, the more confused I get too. Although I do share your sympathy. I would like to see a permanent civilization of humans. I would like to see us master. Some of these systems and learn to work with them and within them and to not burn ourselves out just as we’re getting started seemingly.
But who really knows? Maybe if we’re right, then you can write future pieces arguing about the Sapiozoic against David Grinspoon. You want to live that long?
Peter Brannen: Yeah, I love that idea. And there’s something cool and geological about that too, because like the Cambrian explosion, which people might have heard of, is sort of like when animal life exploded 543 million years ago. And it was... You know, might have been brought on in large part due to these crazy new innovations in biology of sight and chemo reception and this arms race that just exploded. And there’s all this new sort of biological technology on the planet and it totally reworked the whole planet and it gave rise to everything, the entire history of animals that came afterwards.
And in some ways you can imagine that our technology is maybe analogous to The Cambrian Explosion, where it’s this totally new novel phenomenon on the planet that very quickly has reshaped things and for the better and for the worse environmentally, certainly. But maybe we’re at the beginning of sort of this new expansive creative period where technology and humans live in simpatico with the planet, or maybe that’s just going to be this brief little asteroid impact, essentially, of, you know, this thing just bursts onto the scene and burns itself out and So I’m hoping that it’s more like David Grinspoon’s vision for it than the latter.
Ross Kenyon: That’d be good. I would also prefer that. I realize now that I goofed and I didn’t mention your articles at the beginning of this episode. So if you’re listening now, you can find them in the show notes. They’re called The Anthropocene is a Joke. I should really be saying Anthropocene now. You’ve so muddled me, Peter. Anthropocene is a joke. And then in October, your response was, what made me reconsider the Anthropocene? Both are worth reading. They’re both in the Atlantic and the links are in the show notes.
And Peter’s book, which is a great way to start wrapping your head around geology as a whole. Which, as you can tell from listening, is difficult to do, difficult to communicate about. It’s so foreign to our direct experience. But I found this book super useful. I love it. It’s called The Ends of the World, Volcanic Apocalypses, Lethal Oceans, and Our Quest to Understand Earth’s Past Mass Extinctions. God, those last couple of words are so sibilant, Peter. I have a hard time even saying them all in a row.
Yeah, the whole subtitle is a mess. I feel like apocalypses should be singular as a plural, like apokali, apocalypti. It’s Greek, is it not? And I, if it’s plural, this is stupid, right? Apocalypses, I don’t know. This is garbage time. This is when I’ve asked too many questions and the show’s gone longer than it needs to. So thank you for being here, Peter. Yeah, thanks for having me. And then is there any other place that people can find your personal website?
Yeah, there’s PeterBrandon.com. And if they want to read snarky jokes about earth science, I’m at PeterBrandon1 on Twitter. Highly recommend that as well. And if you like the show, please rate and review us on iTunes, Apple Podcasts, or Stitcher. Tell your friends. Try and get someone into geology. Weird them out by talking about deep time without their prior knowledge of what even that is. And just set them up for a confusing day. And thank you so much for listening.
