Ask Andrew Guzman, a professor of international law at U.C. Berkeley, why he decided to write a book about climate change, and he says it’s simple: It’s the biggest issue of our time.

“If I didn’t write about it,” he says, “for my grandkids, I’d sound like somebody who wasn’t interested in Nazi Germany in 1939.”

Guzman doesn’t want to be painted as an alarmist. That’s why, for the book, Overheated: The Human Cost of Climate Change, he assumes that we will see a modest (and increasingly optimistic) 2 degrees C of warming. You know, so as to stay on the conservative side of things.

But it turns out that 2 degrees is enough to sound some serious fucking alarm bells.

Guzman’s main goal, he says, was to look at the social, economic, and political costs of global warming. Most books focus on physical and environmental changes. Guzman wanted to examine human consequences.

Guzman spends a significant portion of Overheated exploring how troubled parts of the world will be affected by food and water scarcity vis-à-vis climate change. But some of the scarier parts of the book are about the overabundance of water that’s coming our way: 2 degrees warming probably equates to about a one-meter rise in sea level this century. That’s enough to displace hundreds of thousands to millions of people in low-lying nations, and, as of now, there is no plan to deal with environmental refugees.

“I think the question is whether the exit will be orderly or emergency crisis,” Guzman says. “If a storm comes at the wrong time and the international community is then plucking these people out of the sea, it’ll be horrible.”

The environmental-refugee problem becomes eye-poppingly scary when you look at the 150 million people living in Bangladesh. A one-meter sea level rise would swamp about 17 percent of the country.

“We know where people go when they lose their land: They go to cities, and they go to refugee camps,” Guzman says. “So the Bangladeshi cities that remain are going to be overrun and crumbling. Just think of the sewage system alone.”

Lest you think no one has considered what might happen next, in recent years India has increased security along the border with Bangladesh. “But fences are only so good up to a point,” Guzman says. “So how much violence are you prepared to use to keep that border secure? It’s not at all clear to me that the border can remain intact.”

Global warming is often couched as an environmental problem, but for Guzman, this misses the point. He’s skeptical that drowning polar bears and acidified coral reefs will mobilize the public into action. He’s a realist appealing to self-interested Americans. This isn’t about hugging trees and saving whales. This is about international security, global pandemics, terrorism — and a moral imperative.

Overheated is a fascinating read in part because Guzman goes out of his way not to be hyperbolic. But if you buy his book as you’re boarding a plane, it’s more likely than not that you’ll land feeling alarmed.

Listen in as I talk to Guzman about how he got involved with this topic, the chances that we’ll be able to avert disaster — and what we’re in for, as a species, if we fail to react in time.

This interview is part of the Generation Anthropocene project, in which Stanford students partake in an inter-generational dialogue with scholars about living in an age when humans have become a major force shaping our world.

The Anthropocene is more than just a fanciful notion held by those who believe homo sapiens has gone totally berserk. Bigwig geologists are taking the idea super seriously. In fact, members of the International Commission on Stratigraphy — the masters of the official geologic timetable — have organized a group of scientists and experts to consider formal adoption of the Anthropocene. The basic task of the Anthropocene Working Group is to try to imagine what the rock record will look like a million years in the future, and to figure out whether we humans will have a lasting enough impact to truly merit an epoch all our own.

To get a peek behind the curtain, the Generation Anthropocene producers recently sat down with four members of the Anthropocene Working Group: Jan Zalasiewicz, the group’s convener; Mike Ellis, head of climate change science at the British Geological Survey; Mark Williams, a paleobiologist at the University of Leicester; and Davor Vidas, an international lawyer and expert on the Law of the Sea.

“The signal — physically, biologically, chemically — will be quite clear,” Zalasiewicz said. “Unless the cavalry ride in, there will almost certainly be climate change on the order of 3-7 degrees globally over the next few centuries. There will be a major sea level rise … Beaches will be covered by offshore muds.”

Ellis added that submerged cities will be preserved for the ages as well: Rising sea levels “will fossilize the various urban structures that we have built over the past few hundred years.”

So those future geologists will see our signs. Now it’s up to Zalasiewicz, Ellis, and Co. to decide whether or not it’s hubristic and premature to say that we’ve kicked off a whole new geologic era. The team will make an official recommendation in 2016.

In the meantime, some members of the working group are concerned with the less academic implications of what we’re doing to the planet. Take Vidas, the lawyer. Rising sea levels will force a serious rethinking of maritime law, he said. “Our international law is the law of the Holocene. However, with the entry into the Anthropocene, with conditions that are not environmentally stable, we may be facing a problem.”

Every geologic boundary marks a redefinition of the terms of life on Earth, which is why the Anthropocene debate has that rare quality of being simultaneously academic and socially relevant. It is an exercise of deep-time imagination, but with real-world, right-now implications. So strap on your geology goggles and dive into the Anthropocene with the masters of the geologic timetable — for the 50th episode of Generation Anthropocene.

This interview is part of the Generation Anthropocene project, in which Stanford students partake in an inter-generational dialogue with scholars about living in an age when humans have become a major force shaping our world.

When Charles Darwin wrote, “Multiply, vary, let the strongest live and the weakest die,” do you think he thought to himself, “Dude, I’m about to piss a bunch of people off”? Or when Copernicus and Galileo forwarded the idea that the Earth revolves around the sun, and not the other way around, do you think they were trying to ruffle Vatican feathers?

Well, OK, maybe these guys saw trouble brewing. But another, contemporary scientist didn’t. In the mid-1990s, Benjamin Santer authored a chapter in a report of the Intergovernmental Panel on Climate Change that included this sentence: “The balance of evidence suggests a discernible human influence on global climate.”

Innocuous enough, right? But it would prove to be a pivotal moment for the discussion of global warming. Today, the political cacophony surrounding climate science is so loud that it drowns scientific reasoning like a Jack White solo at a Simon and Garfunkel concert. And much of the noise can be traced back to that sentence.

I recently sat down with Santer, a MacArthur Award-winning researcher at Lawrence Livermore National Laboratory, to get his firsthand account of the day the global warming show went from soft acoustic to power-blasting electric.

“I was blissfully unaware of what would happen at the end of 1995,” he told me. “The only thing I thought about was doing the best possible science and searching for that holy grail of objectivity.”

Things quickly got nasty — and they’ve stayed that way ever since. “Nothing in your scientific training prepares you for that kind of challenge to your integrity,” Santer says. “You’re prepared as a scientist to stand up there and defend your research, but you’re not prepared to have people call you a liar or a cheat.”

Still, science is all about challenging assumptions, even if those assumptions are near and dear to the masters of the universe. “In the end, we can’t embrace ignorance with open arms,” Santer says. “Reality is overtaking us.”

Here’s my interview with Santer, in which he describes controversy surrounding the 1996 IPCC report, the travails of being a scientist under fire, and why he has decided to stick with it, even in the worst of circumstances.

This interview is part of the Generation Anthropocene project, in which Stanford students partake in an inter-generational dialogue with scholars about living in an age when humans have become a major force shaping our world.

Imagine for a moment that planet Earth isn’t running out of anything. We have plenty of food, plenty of oil, plenty of rare minerals, and plenty of air. In this little utopia, the only constraint is space. We can breed like bunnies, and everything is fine — until we hit what I call Peak Elbowroom.

This is more or less the idea behind a series of experiments conducted by John B. Calhoun in the 1960s. Calhoun offered a group of rats a limitless supply of food, water, bedding, and everything else healthy, happy rats could want — except space. He kept his rats confined in “rat cities” — elaborately partitioned boxes designed to simulate the urban environment, which he built in his basement in Washington, D.C.

So what was the rat response? Turns out they all died. Well, they went big, then died. The population spiked and plummeted in a blaze of rodent self-extermination.

It wasn’t for lack of resources, obviously, but just from the sheer stress of it all. They were fat, happy, and multiplying. Then Peak Elbowroom hit, and then they went berserk, became anti-social, stopped breeding, and then … Poof. Gone. Completely extinct. Calhoun repeated the experiment several times, always with the same results.

Back in the ’60s, Calhoun saw his experiments as a metaphor for the human experiment — and who wouldn’t, right? After all, this was the decade of The Population Bomb, when scientists predicted the Earth was reaching its human-carrying capacity.

The human population didn’t crash, of course — at least it hasn’t yet. But last year, we soared past 7 billion people on the planet, and talk of the Earth’s carrying capacity reared its head again. With that in mind, first-time filmmaker Mike Freedman decided to resurrect Calhoun’s rats. In his new documentary, Critical Mass, he tethers their story to our own oh-so-tricky subject of resource binging and population growth. Here’s the trailer:

Freedman doesn’t pretend that Calhoun’s rats are a direct analog for humans, but, he says, “We see ourselves in it instinctively. It’s a very human trait to anthropomorphize.” Nor is the film about population control. Instead, he says, his intention was “to open a conversation.”

Which is not to say Critical Mass is apolitical. It does, however, strive for the wide view of human self-organization. Throughout the film, an army of experts weigh in on head-spinning issues like poverty, urbanization, peak oil/water/food, and, of course, environmental degradation.

The result is a film that is well-crafted, provocative, and stark. Critical Mass raises important questions about how we choose to live on our limited planet. We strive for equality — or at least to provide every human with his or her basic needs. But that is becoming more and more difficult as we race towards Peak Elbowroom.

Check out my interview with Freedman, below. The young filmmaker is clearly honing in on the big questions of our day with intense focus and specificity. He’s also one hell of a conversationalist.

And if you like what you hear, Freedman and his team are in the midst of a fundraising campaign to distribute the film. Learn more at the Critical Mass homepage or on Indiegogo.

This interview is part of the Generation Anthropocene project, in which Stanford students partake in an inter-generational dialogue with scholars about living in an age when humans have become a major force shaping our world.

Michael Shellenberger and Ted Nordhaus have a real knack for stirring the pot.

In 2004, the duo, founders of an Oakland, Calif.-based think tank called the Breakthrough Institute, published a paper called “The Death of Environmentalism: Global Warming Politics in a Post-Environmental World.” Much to the chagrin of many old-school greens, they argued that the institution of environmentalism was unable to deal with the global crises knocking at our door, because environmentalists were pigeonholed by what they called “the politics of limits” — that is, enviros keep prophesying the End Times, only to be proven publicly and embarrassingly wrong. (Grist ran a whole series about the ensuing melee under the banner “Don’t Fear the Reapers.”)

At the core of the Breakthrough philosophy is the belief that human ingenuity will trump all of the doomsaying, allowing us to survive and adapt to a warmer world. To take a recent example, Breakthrough has been steadfast in critiquing a hypothesis, first proposed in a 2009 Nature article, arguing that there are nine biophysical limits in the Earth’s cycles that, when crossed, lead to irrecoverable harm for humans. From Breakthrough’s perspective, this notion of “planetary boundaries” is misguided. They don’t dispute that this growth will come at a cost to the environment, they just argue that our limits will be self-imposed. We can grow and grow, as long as we don’t care about having tropical forests, polar bears, or coral reefs. (Ed’s note: they don’t propose that we wipe out said forests, bears, and reefs — just that the choice is ours.)

In reading through the Breakthrough literature, it would be easy to characterize Shellenberger, Nordhaus, & Co. as climate skeptics or deniers — they are certainly quick to criticize those who predict imminent disaster. But to do so would be to oversimplify their arguments. Instead, they are trying to put climate change into a broader context — one that includes other challenges such as hunger, poverty, and access to clean energy, as well as a more realistic (in their opinion) sense of our abilities to innovate our way through sticky circumstances.

“Whenever liberals try to make it a life-or-death situation — whether it’s on environmental policy or social policy — it just rings false,” Shellenberger told me in a recent interview, “because it is false.”

This is the allure of the Breakthrough philosophy: Rejecting the apocalyptic narrative so common in environmental circles will, they say, one, allow us to finally gain traction with a public that is tired of all the doom and gloom, and two, clear the way for the innovation we’ll need to thrive in a warming world.

Then again, maybe this is about life or death. Maybe the stakes are higher for the planet than Shellenberger and Nordhaus are willing to admit. Only time will tell. But there is at least one point on which these firebrands and environmentalists can agree: In the new Age of Humans, we have stark choices when it comes to who wins and who loses.

Here’s my interview with Michael Shellenberger, in which he talks about planetary decisions, Malthusian scientists, and the quaint notion that there are pressing physical limits on human growth.

This interview is part of the Generation Anthropocene project, in which Stanford students partake in an inter-generational dialogue with scholars about living in an age when humans have become a major force shaping our world.

• A billion people go to bed hungry every night, and another billion aren’t too far from that.
• We’re about to add another 2 billion people to the global population.
• The planet is warming (fast), meaning more heatwaves and drought, which is bad news for growing food.

Translation: It’s going to take more than backyard chicken coops and window-box gardens to get us through the next few decades.

“People like Michael Pollan are good at making people realize where their food comes from, and the externalities of food production, but anecdotes can be very misleading,” says professor David Lobell, associate director of Stanford’s Center for Food Security and the Environment. “In California, we have great climates and great soils, but in Africa, organic agriculture results in very low productivity, and very persistent poverty.”

Lobell doesn’t deny the environmental impacts of industrial farming, but he does think we’re going to need some of its heavy-duty tools if we’re going to feed 9 billion people without converting what remains of wild nature into farms.

“The question for me is not whether we can produce enough food, but whether we can produce enough food without destroying the environment in the process,” he says. “Thirty to 40 years from now, we’re either going have large chunks of the Amazon growing soy beans and other things … or we’re not. If we can’t meet the basic needs of people, then I don’t think the prospects for the Amazon are good.”

Take a listen as Lobell and I discuss the ramifications of climate change on food production, how food scarcity and price shocks contribute to global political unrest, and what it’s like to receive hate mail at 7 a.m.

This interview is part of the Generation Anthropocene project, in which Stanford students partake in an inter-generational dialogue with scholars about living in an age when humans have become a major force shaping our world.

In 2000, Nobel Prize-winning chemist Paul Crutzen suggested that humans have had such profound and far-reaching impacts on the planet that we have ushered in a new geologic age – the Age of Man, or, as Crutzen called it, the Anthropocene. The idea has been bouncing around the halls of academia ever since, and in the last few years, it has jumped from the ivory tower into popular literature and a few geek-tastic conversations over beer. The notion that humans now run this joint seems to have struck a chord.

Just getting up to speed? The team from the Generation Anthropocene podcast at Stanford University sat down in the recording studio and tried to explain everything in five short minutes. (It ended up taking seven, but who’s counting?) Just for fun, they did it game-show style. Here they are talking about the basics of the Anthropocene, the arguments for and against adding it to the official geologic timetable, and why the idea is so catchy:

Also:

• Grist’s David Roberts explains why the Anthropocene is so hard for people to get their heads around and links to a cool video.
• If you really want to dive deep, the Royal Society dedicated an entire issue of its Philosophical Transections to the Anthropocene.
• Find Generation Anthropocene’s interviews about our new age on Grist, or go straight to the source.

“Should we be like gods? Should we control the whole thing — who gets food, what the weather is, where it will rain, what species get to live and die?”

-Susanne Moser, climate researcher, consultant, and Aldo Leopold fellow at the Stanford Woods Institute

About two months ago, the Generation Anthropocene radio team was invited to Santa Cruz for a conference for the Aldo Leopold Leadership program in environmental science. Leopold was one of the grand old dudes of the environmental movement, and you probably think that a program sporting his name screams “old white man reeking of patchouli.” But the conference was actually really cool.

Sure, there were plenty of old-school, save-nature-’cause-it’s-really-neat conservationist types. But the Leopold fellows are world leaders in the environmental sciences. They’re smart as hell, if not a bit dorky. The Leopold program trains scientists to communicate their work with a broader audience, and its leaders are especially interested in catching the ear of the next generation.

As they put it, they’re tired of the “gray hairs” in the room. They want to know if we give a damn about climate change, mass extinction, and the global binge on natural resources.

Well, we wondered, why should we care?

One response from environmental scientists is that nature provides big bucks when you run the numbers. Whether you want to filter water, pollinate crops, or have microbes to chew up toxic waste, it turns out the planet (i.e. wetlands, bees, etc.) can do it a whole lot more cheaply and efficiently than we can. Those in the know call these “ecosystem services,” and proponents love to number-crunch the cash value of the planet in order to coerce the world to go green.

Then again, there’s something bizarre about slapping price tags on every last critter in every corner of the planet. How much is an axolotl — a crazy Pokemon-like salamander living in the wetlands around Mexico City — worth? How do we justify saving endangered species if they aren’t delivering the return on our capital investment?

That’s where the old-school “save nature for nature’s sake” argument comes in — and we found a few folks at the conference who were arguing for that, too.

The debate over why to save nature goes back over 100 years, but it has never been more relevant than it is now, in the Anthropocene — the geologic age of man, where we’re calling the shots.

In this episode, we bring you excerpts from our interviews with a half-dozen experts, covering everything from weeds to shades of green to that crazy Mexican salamander (which apparently doesn’t taste half bad) …

Free MP3. (Right click, select “Save Link As.”)

This interview is part of the Generation Anthropocene project, in which Stanford students partake in an inter-generational dialogue with scholars about living in an age when humans have become a major force shaping our world.

Witness Charles Darwin. You may think of Darwin as a biologist, because he gave us an appreciation of the spectacular biodiversity of the planet. Geologists, however, claim his as their own: For evolution to work, you need a WHOLE lot of time. Darwin understood this. He’d studied geology.

More recently — in the last couple of years, to be exact — geologists have brought us another show-stopping concept. They call it the Anthropocene. Literally, anthropocene means “the age of humans.” We humans, the thinking goes, are a geologic event like asteroid impact or the end of an ice age.

At first this sounds like a joke. When you look at it through the long lens of earth history, our occurrence appears as an insignificant blip. We’re the last second on a 24-hour clock, the last inch before the end-zone on a football field. We’re nothing. We’re tiny. We’re a fraction of a percent, an evolutionary remainder.

But, if you think about it, there are, in fact, some very good reasons to think that we’ve created a new geologic age. We’ve certainly changed the terms of life. We killed off the woolly mammoth and the dodos, shipped pythons from Burma to Florida, and created breeding grounds for rats, raccoons, pigeons, and other urban-loving creatures. Throw climate change and ocean acidification into the mix, and it’s easy to make a case that our influence surges from continental to global. Even if a virus wipes us all out tomorrow, our impacts on the planet will be felt for a long time to come.

Do we deserve our own geologic epoch? Geologists are still debating that point. We usually reserve these things for major planetary transformations, from the evolution of multicellular organisms to the extinction of the dinosaurs. Whether or not we get our own, however, the idea is worth thinking about.

That’s why I petitioned my department at Stanford to let me teach a class about the Anthropocene. (It’s true. I’m a geologist. I’m finishing up my PhD in geosciences.) My idea was to have Stanford students pick faculty working on 21st century environmental issues. The students would then sit down with their subject for an hour to record a conversation about what the Anthropocene is. More importantly, I wanted them to struggle with what it means to be living in a new geologic age. They’re the ones inheriting the planet, so, to my mind, their voices are perhaps the more important ones.

Our students were free to pick anyone. They didn’t have to be geologists, or even scientists. Some picked historians, engineers, or religious studies professors. Our class worked like a newspaper editorial boardroom, where everyone pitched ideas, collaborated, and critiqued each other’s stories. We recorded the interviews at our college radio station, KZSU, and then edited the audio into digestible pieces. Since we view our project as an inter-generational dialogue, we decided to call it Generation Anthropocene.

Over the next few months, we’ll release an episode of Generation Anthropocene each week on Grist, starting with this one, a compilation of excerpts from all of our interviews that serves as an introduction to the series.

Free MP3. (Right click, select “Save Link As.”)

At the heart of it, we’re trying to reconcile the immense time scales of earth history with everything we know about human history. We’re aiming for a balanced perspective and fresh eyes on the future of our inevitable engagement with the environment. More than anything, we believe that the power to imagine vast amounts of space and time is exactly the same power needed for benevolent stewardship — for life in the Anthropocene.

We hope you, too, walk away feeling a little more prepared for life in the new age.