Climate Change Is 'Greatest Challenge Humans Have Ever Faced,' Author Says

DAVE DAVIES, HOST:

This is FRESH AIR. I'm Dave Davies, in for Terry Gross, who's off this week. If you want to hear some alarming facts about climate change, Bill McKibben has them. He writes in his new book that as the Earth warms, we're now seeing lethal heatwaves in some parts of the world and that the largest physical structures on our planet - the ice caps, coral reefs and rainforests - are disappearing before our eyes.

McKibben's been writing about and advocating for action on climate change since the 1980s, but his new book isn't just a warning of impending disaster. And it isn't just about climate change. McKibben says there are also threats to humanity as we know it from human genetic engineering and from the unbridled development of artificial intelligence. Bill McKibben has written 15 books and is the founder of the environmental organization 350.org. His new book, which offers some dark visions of the future and hope for real change, is called "Falter: Has the Human Game Begun to Play Itself Out?"

Bill McKibben, welcome back to FRESH AIR. You know, you note that climate change is such a familiar term that - you know, like urban sprawl or, you know, gun violence that it's sort of a part of our journalistic lexicon. And there's been a lot of alarming information about climate change. And when I read your book, I found even more alarming information. And I think it's worth dwelling on it just a little bit. One of the things that struck me was heat waves - not heat waves 50 years from now but heat waves today. What are we finding?

BILL MCKIBBEN: Well, we're already finding heat that taxes the ability of the human body to endure it. The highest reliably recorded temperatures on Earth have happened in the last couple of years. They've been in parts of the Mideast and the Asian subcontinent where city temperatures have reached 129 degrees. When they try to factor in the humidity and dew point, people have been describing - feels like temperatures as high as 165 degrees. I mean, 129 degrees Fahrenheit - that's about where my oven begins, you know? And a human being can survive it maybe for a few hours inside, in the shade. But they can't survive it long term. And the scientists are telling us without any hesitation that, on current trends, by the middle or latter part of the century, vast swaths of the planet will be experiencing those temperatures for weeks on end. And there'll be, in essence, no-go zones for human beings, no-go zones in those continental interiors but also, of course, no-go zones along the coasts where the oceans are rising and where storms are getting more powerful. The game board on which we play the game of human beings is shrinking and shrinking dramatically for the first time since humans wandered out of Africa and started expanding their range.

DAVIES: It's shrinking because coastlines are receding but also because there are places where people can only survive by cowering together in air conditioning.

MCKIBBEN: That's right. And there've become severe limits to how long you can make that work. Already, the World Labor Organization (ph) says that human beings are able to do about 10 percent less work in the course of a day outdoors than they used to be able to. It's simply gotten too hot and too humid. By mid-century, that number will be something like 30 percent less work. Really, the ability to be human is starting to vanish in many, many places.

DAVIES: What's happening with food supplies? And what can we expect?

MCKIBBEN: Well, human beings have had a great run of increasing their supply of food since the end of World War II. But as the Green Revolution begins to play itself out, coming the other direction are these vast heatwaves and shortages of water. And so we're already seeing real effects. I mean, the Arab Spring was triggered in large part by the rise of wheat prices that followed epic drought. The hideous civil war in Syria was triggered in part by epic drought, the deepest drought in the history of what we used to call the Fertile Crescent, that drove a million farmers off their land and into the already destabilized cities of the brutal Assad regime. And we see how those things play out not just in those places but around the world. The refugees that streamed out of Syria were enough to undermine the politics of Western Europe. The refugees now fleeing the highlands of Guatemala and Honduras, where drought has made raising crops an ever iffier proposition, they're, you know, showing up on the southern border and being used as scapegoats by the most vicious elements of our political culture.

DAVIES: So climate change-related drought is what's driving the surge of immigrants?

MCKIBBEN: There's a terrific story on the front page of The Sunday Times talking about precisely how destabilizing the drought and heat has been. If you look at a map of Central America, it's one of the few places in the world where there are big oceans close by on either side. As, you know, the oceans are soaking up most of the excess heat that we're producing. And that makes places like that particularly vulnerable to kind of whipsaw changes in temperature.

DAVIES: And fire. I mean, we've focused a lot on the fires in California because they are nearby. And we see them on television. And they've affected and killed a lot of people. But you write that there are really alarming fires in other parts of the world that we don't pay as much attention to.

MCKIBBEN: There are fires in places where there never used to be. I mean, we're seeing routinely now fires 3, 4, 5 degrees of latitude north of where we ever saw them - across Siberia, across much of the Arctic. It's just gotten too hot and too dry. But we shouldn't skip lightly over those California fires, either. I mean, when you look at a place literally called Paradise that literally turned into hell inside half an hour, you begin to understand how the psychological space that we inhabit is beginning to shrink, too.

DAVIES: You know, you also write about - the city of Houston, for example, has taken on so much water through Hurricane Harvey and an earlier storm that the sheer weight of it actually made the city sink a couple of centimeters. And I wonder - you know, some people said don't confuse weather with climate. You can't connect any specific weather event to climate change. Is it clear that we're seeing something different in the weather as a result of what's happening to the planet?

MCKIBBEN: Yeah, absolutely. Scientists have gotten good at what they call attribution studies. They say, for instance, in the case of Hurricane Harvey that the rainfall was about 40 percent heavier than it would've been without the heating that went on. Warm air holds more water vapor than cold. You get more evaporation. That's why in arid areas, you get more drought. But then once that water is up in the atmosphere, it comes down. And it comes down increasingly in deluge. I mean, look. The - Hurricane Harvey's the perfect example. There were parts of Houston that got near onto 5 feet of water. Not long afterwards, we had the biggest rainfall in the history of the East Coast with the hurricane that hit the Carolinas last fall. It dumped the water equivalent of all of Chesapeake Bay on the Carolinas. So these are entirely unprecedented. And they're happening everywhere. The most tragic example at the moment perhaps is what's going on in Mozambique where Cyclone Idai is being called the worst natural disaster in the history of the Southern Hemisphere. It flooded a vast part of Mozambique, Zimbabwe and Malawi.

DAVIES: And before we leave this subject, what is expected in terms of climate refugees in the coming decades? That is to say people who have no choice but to flee either the encroachment of the sea or other changes associated with climate change?

MCKIBBEN: The low end of the U.N. prediction is on the neighborhood of 200 million. The high end is closer to a billion. And as we said before, if you look at the havoc that...

DAVIES: And that's how soon? How soon is that?

MCKIBBEN: In the course of the century, yeah. If you look at the havoc wreaked by a million refugees coming out of the Middle East or Central America, you get some sense of how unprepared as a world we are for that. This is one reason why, whatever else you might want to say about them, the Pentagon has, at least in this respect, been quite reality-based. And while the rest of Trump's Washington is pretending climate change doesn't exist, the Pentagon continues to warn that this is a huge threat to stability, which it is, because people on the move are, by nature, destabilizing.

It's one of the most fraught things we have coming at us. The idea that anybody's going to be immune from this anywhere is untrue because even, if at the moment, your part of the world is not suffering through some catastrophe, it's going to be dealing with the people who are.

DAVIES: Our guest is Bill McKibben. His new book is called "Falter: Has The Human Game Begun To Play Itself Out?" We'll talk some more after a short break. This is FRESH AIR.

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DAVIES: This is FRESH AIR. Our guest is Bill McKibben. He's been writing about and advocating for action on climate change since the 1980s. He's written 15 books. His latest is called "Falter: Has The Human Game Begun To Play Itself Out?"

In the book, you talk about what we've known and what we've done about this, going back to the '80s, when scientists began to clearly identify what was happening and the threat that it posed. And somehow, our politicians - even those, you write, who recognize the change - have just engaged in baby steps when serious measures are needed. Why?

MCKIBBEN: Well, the story of why we've done so little is, in some ways, the most painful part of this whole affair, you know? When I wrote "The End Of Nature," I was 27, and so it did not occur to me that our institutions would show themselves to be so timorous and slow. We've come to understand more of how that happened in the last few years.

Great investigative reporting at places like The LA Times and The Columbia Journalism Review and InsideClimate News and elsewhere have documented, beyond any doubt, that the fossil fuel companies knew everything there was to know about climate change in the 1980s. They knew how much it was going to warm and how fast, and they believed it. I mean, Exxon began building all its drilling rigs to compensate for the rise in sea level they knew was coming.

What they didn't do was tell any of the rest of us - just the opposite. Beginning right about 1989 or so, they began to pour huge sums of money into this architecture of deceit and denial and disinformation that kept us locked for 30 years in a sterile debate about whether or not global warming was real, a debate that both sides knew the answer to at the beginning. It's just one of them was completely willing to lie, and that lie turns out to be the most consequential lie in human history, I think. It's the thing, more than anything else, that's kept us from reacting with any speed or vigor to the greatest challenge humans have ever faced.

DAVIES: Right. And I just want to note - since, Bill McKibben, you're an activist on this and have a strong point of view - that there's a very rich documentary history of this on the Internet if anybody wants to look it up and kind of look at what Exxon says, which is that this is a distorted view of what they did. I mean, I did note that a couple of Harvard researchers looked at this and concluded that, yes, there were moments when Exxon placed, you know, advertorials or, you know, paid statements which acknowledged the human nature of climate change and the need to fight it, but that when you look at where most of their communication was, and particularly where they put their money into research and advocacy, it was to question the reality of it all.

MCKIBBEN: Yes. I mean - and it's completely true that I'm an activist, but it's also true that there are hundreds of footnotes in this book. I'm a reporter and writer above all. And this is just part of the story that's, I think, beyond any real doubt. The question now is how to pick up the pieces.

Here's the problem. Thirty years ago - and I suppose I should avoid saying, you know, if only you'd listened to me when - but 30 years ago, there were relatively small things we could've done that would've changed the trajectory of this battle. A small price on carbon back then would've yielded a different trajectory, would've put us in a different - we might not have solved climate change yet 'cause it's a huge problem, but we'd be on the way.

Having wasted 30 years, doing nothing at the behest of the powers that be, we're now left with a set of very uncomfortable and difficult choices. We have to move much more quickly than is convenient, politically, economically, socially. But what choice do we have? I mean, in the end, this isn't a fight between Republicans and Democrats or environmentalists and industry. It's, in the end, a fight between human beings and physics. And physics is poor at compromise, doesn't negotiate easily. We're going to have to do what physics demands.

DAVIES: You know, you write that another element of this is that around the time that this issue was raised by a lot of scientists in the 1980s, you saw inequality in the country, inequality in wealth and income increasing and a lot of players in the political and intellectual world pushing a different vision of the relationship between government and individuals, which really found some purchase. You want to just talk about that a bit?

MCKIBBEN: Sure. Look. The - this was one of these perfect examples of bad timing. Right at the moment that the reigning ideology in America - the most important country on Earth, at least during this period. Right at the crucial moment, its reigning ideology became a kind of laissez faire capitalism - unregulated capitalism. Let markets solve all problems. Government, as Ronald Reagan said, isn't the solution. It's the problem - on and on and on. That meant that there was no appetite for doing the kind of regulation that we needed to do to try to rein in climate change when it was easy to do it. That organized selfishness - that's set us back and set us back hard.

We're beginning to see the reaction to it with things like the Green New Deal and a big, new focus on dealing with inequality and with climate change and figuring out how they mesh together. It's just that we've waited a long time.

The thing never to forget, Dave, about climate change is it's the first timed test that humans have ever had. And the time part is what scares me. It's too bad that this moment of ideological ascension just happened to come in the time and the place when there was enough leverage that, perhaps, it broke the planet in the process.

DAVIES: You know, it also occurs to me that one of the fundamental problems in the past 30 years and ongoing is that, you know, yes, we are one species, and we share the same planet. But our instrument of policy is primarily nation-states who compete with one another and, you know, are unlikely or can be resistant to making change if others don't or can point an accusing finger, you know, like, I'm not as bad as they are. How much of that is the problem? And how do we overcome it?

MCKIBBEN: Well, it is a big problem. And it's one of the reasons that action has been so slow. I fear that the biggest part of that problem may be right here. I mean, you'll remember that the world finally managed to reach, at least, a beginning of an effort to do something about this at the Paris Accords in 2015 - not anywhere near a perfect agreement but certainly a start and the first time that all the countries of the world came together to pledge some kind of action.

And then you'll recall that our president pulled us out of it. You know, the country that has poured more carbon into the atmosphere than any other over the course of human history is also the only country on the planet unwilling to even pay lip service to taking on this problem.

The good news is that some other countries seem to be sort of rising to the occasion. China is putting in renewable energy at a pace like we've never seen on the planet before. Maybe even more importantly, India - which is, in energy terms, probably where China was 15 or 20 years ago - seems like it might be poised to become the first great nation that, at least to some degree, skips over the coal-fired part of development and moves straight to renewable energy.

The engineers have done such a remarkable job over the last decade - the price of a solar panel has fallen 90 percent - that it simply makes no economic sense anymore to keep doing what we're doing. And that's why, at the moment, India, for instance, is building far more renewable energy than they are conventionally powered power plants.

DAVIES: You know, one thing that you write about in the book, which I didn't know, is that the coal industry is promoting itself as the solution for economic poverty or energy poverty in much of the developing world.

MCKIBBEN: This was their big shtick a few years ago as protest and activism began to erode their market share in places like the U.S. They - kind of like Philip Morris before them - turned to the developing world as their salvation, arguing that they were somehow going to solve energy poverty and turn on the lights for places where they hadn't been before. It turns out that they were either insincere or dead wrong about that argument. That's not what's turning on the lights. Ninety percent of the people who are getting power for the first time now are getting it from renewable energy because it's so cheap.

DAVIES: Bill McKibben's new book is "Falter: Has The Human Game Begun To Play Itself Out?" After a break, he'll talk about two other developments he says could threaten humanity as we know it - human genetic engineering and artificial intelligence - and why he says there's still hope for meaningful change. Also, rock critic Ken Tucker reviews a new album from the British band The Mekons. I'm Dave Davies, and this is FRESH AIR.

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DAVIES: This is FRESH AIR. I'm Dave Davies, in for Terry Gross, who's off this week. We're speaking with writer and environmental activist Bill McKibben. His first book, "The End Of Nature," became a bestseller in 1989 and ignited debate about climate change. He's written 14 books since and founded the environmental organization 350.org. His new book is called "Falter: Has The Human Game Begun To Play Itself Out?"

The book isn't just about climate change. I mean, you are looking at what you say is the human game - this great endeavor - and whether it is sustainable in the coming years. And you identify a couple of other threats to humanity as we know it. One is genetic engineering. Why?

MCKIBBEN: Genetic engineering of human beings - you probably saw this story on the front of the Times over the weekend about the doctor in China who apparently, with American help, managed to produce the first two designer babies in the world, a pair of twins in China who'd been genetically altered. This feels like where we were decades ago with climate change - right on the cusp of revolutionary shifts. And those shifts are things that we should take very seriously. We overestimated and took for granted the physical stability of the planet, refused to believe that it could change. We take for granted the idea that human meaning is eternal, too.

But think about what happens if we go very far down the road that a lot of scientists and a lot of entrepreneurs have described - a world where you go into a clinic and put your money down and design, to the best of science's ability, the child you want to produce. You may soon be able to figure out how much serotonin, you know, your child produces in an effort to regulate its mood. You may be able to affect, in some way, small or large, its intelligence.

Think about what that means - first, the fact that the minute you turn a person into a product, that product faces the inevitable fate of all products - obsolescence. You've been in the clinic with your first kid, put down your money, made your selections. OK. You come back five years later for kid number two. Technology has marched on. You're able to get better upgrades for this one.

These are changes that we should avoid and that we can avoid without risk to human health. We know other ways to prevent the transmission of genetic disease and things. This is a real challenge to human beings, I think, and one that we haven't taken seriously enough yet - that these two Chinese babies born last fall seem to have sobered up some of the scientific community. And there's been increased talk about regulation within and outside of the scientific community to try and slow things down.

DAVIES: Well, you know, in addition to the issues that you raised, you know, we have a lot of inequality. This - these kinds of treatments would cost money over time. Does it end up with, really, kind of two scales of human beings, one which are - have better mood regulation, who are intellectually brilliant, athletically powerful, and then others who can't afford this? I mean, where does that take us?

MCKIBBEN: The head of one of the gene companies at the moment - a Princeton professor - said some years ago that it was only a matter of time before we bifurcated into two species. He called them the GenRich and the naturals. And he predicted that it wouldn't be long before they wouldn't be able to even breed with each other, much less want to, because they'd be on very different paths. This is a way of taking the shameful inequality that mars our society now and that one hopes we are in the process of rebelling against and figuring out how to start changing - it takes that inequality and etches it into our genes.

DAVIES: Describe the Chinese baby experiment.

MCKIBBEN: A doctor in China, in embryo, altered the genetic makeup of twin girls in order to produce - to make it impossible for them to get HIV. As every doctor and other authority pointed out once this became public, this - even if you wanted to do this kind of work, this was in - a bad place to start because there are a thousand easy ways to make sure you don't get HIV once you're born. This was just an attempt at a kind of proof of concept - to be the first person who produced a designer baby. That's why people reacted strongly to it. Even, I'll say, the Chinese government reacted strongly to it. And this researcher is in a good deal of trouble, as he should be, for proceeding blindly down this path.

DAVIES: The other threat you identify is artificial intelligence, and this is really interesting stuff. Let's just start by defining it because a lot of us think we know what it means and don't. What is artificial intelligence?

MCKIBBEN: (Laughter) Well, the definitional problems are rife in the field. Suffice it to say, there's several different kinds. We already have specific artificial intelligences, right? We have computers that are able to - programs that are able to beat human beings reliably at chess and pretty much every other game. And now we're weaponizing them to do all kinds of things, some of which are really dark.

There was a story in the paper about the fact that the Chinese have developed an AI algorithm that can facially identify Uyghur Muslims anywhere in China and pick them out of crowds in any city. And police departments are deploying this across the People's Republic in order to keep track of this racial minority. That's one of the things we have, I'm afraid, to look forward to in the future.

The deeper fears - the sort of real fears about human meaning come when you posit, as many, many scientists do, what they would call general artificial intelligence - AIs designed not for specific tasks, but for broad intelligence - able to teach themselves and to learn and to quickly become more intelligent, maybe a lot more so than human beings. The scientists who work in this field tell us that this is going to happen soon. The definition of soon ranges from 2025 to 2050 or 2060, but those are the consensus predictions within the field. And we haven't at all begun to think out what that means. We've started to worry that people will lose their jobs to automation, which is something very much to worry about, but we haven't really thought about what it means to replace ourselves with something above us.

DAVIES: You know, I'm struggling to understand kind of what the threat is posed by this kind of artificial intelligence, and part of it's because we just don't...

MCKIBBEN: Well, that's 'cause you need to be...

DAVIES: Right.

MCKIBBEN: ...Upgraded so you'll caughten (ph) on more quickly, Dave.

DAVIES: Right. My grandson will have the chip that can do that. But, I mean, to be specific - I mean, there's the movie "I, Robot," where the robots eventually learn that - they start killing human beings on the street because they've taken over. There are a couple of examples in the book of how you give a robotic intelligence a goal, like making paper clips - right? - or...

MCKIBBEN: This is the classic canonical example in the field. You assign artificial intelligence the task of making paper clips, and it won't be deviated from this task. It gets - it pursues it single-mindedly, as only a machine could, and figures out how to keep you from turning it off 'cause that's not a very hard task for a super intelligent machine. And it figures out how to divert all - in fact, all the powers of the planet to making yet more paper clips until pretty soon, we're reduced to a kind of pile of them. We haven't taken it seriously because it doesn't, at the moment, seem to impinge on our day-to-day life. But one of the things that climate change taught me is that things happen fast - like, really fast. And before you know it, they're out of control. So the time for thinking about them is when there's still some chance at getting a handle on them.

DAVIES: Bill McKibben's new book is called "Falter: Has The Human Game Begun To Play Itself Out?" We'll talk some more after a short break. This is FRESH AIR.

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DAVIES: This is FRESH AIR. Our guest is Bill McKibben. He's been writing about and advocating for action on climate change since the 1980s. He's the author of 15 books. His latest is called "Falter: Has The Human Game Begun To Play Itself Out?"

The last section of your book is called "Outside Chance" - you know, hope, but just a little bit, maybe. You said you find hope in two new technologies. One is the solar panel, and you say you kind of fully realized its possibilities on a reporting trip to Africa. What did you find?

MCKIBBEN: Look. I'm a good child of the American suburbs, so I grew up taking everything we take for granted for granted. And I got into Ivory Coast and Ghana and Tanzania into remote villages where people have never had electricity. I was sitting around one day with elders in this community in Ghana who had just had their first power from a solar microgrid. It was hot 'cause it's always hot there, and they kept handing me bottles of cold water to drink, for which I was grateful. But it took me a good 15 minutes to figure out why they were so proud of that. It's because there'd never been anything cold in this hot place before until solar panels had allowed them access to electricity.

If you look at it that way, a solar panel is Hogwarts-scale magic, man. You point a sheet of glass at the sun, and out the back comes light and cold and information and all the things of modernity. And it does it without causing the damage that burning fossil fuels does. It's pretty magical stuff.

DAVIES: Right, and it can transform a home or a village in Africa. Can it scale up to meet the energy needs of an industrial society?

MCKIBBEN: We used to wonder about that. Two things have happened in the last little while. One is this dramatic fall in the price of solar panels and wind turbines. The other is a dramatic fall in the price of storage batteries. So now we're at the point where the fact that the sun goes down at night is not a deal-breaker. Increasingly, we're able to take that power and store it. There was a story in Bloomberg a couple of weeks ago saying that solar-plus batteries is now cheaper than natural gas, even in much of the United States. So even without the dire threat posed by climate change, we'd probably be moving in this direction. Because of the dire threat posed by climate change, we should be moving in this direction as fast as it is possible to imagine doing.

DAVIES: Right. You live in Vermont. Do you have solar panels in your house?

MCKIBBEN: I have solar panels all over my roof. And I'm glad for them, but I try not to fool myself that that's how we're going to solve climate change. We're past the point where we can do this one house at a time. That's the other kind of miracle technology that we have to work with now from the 20th century. It's this idea of nonviolent movement building, the idea that individuals can become a little less individual and join together with others to form movements big enough, maybe, to take on even the power and wealth of the fossil fuel industry.

DAVIES: Yeah. Well, you know, it struck me that one of the things that was interesting about what you found in Africa was that these solar panels were being sold by entrepreneurs, right? I mean, there's money to be made in this. What about the big energy companies taking this on and making that their project?

MCKIBBEN: Well, you would've thought they would've 30 years ago. And the reason they didn't is because you can make money off the sun and the wind, but you can't make Exxon kind of money. And the reason is that once the solar panel's up there on your roof, the sun comes for free.

From Exxon's point of view, that's the stupidest business model possible. They've spent a century getting people to write them a check every month for another delivery, but the sun delivers it for free. That's why they've worked so hard to derail this technology. And it's why, if we deploy it and as we deploy it, not only do we do something about climate change, we also may do something about the imbalances of power and wealth in our society, much of which is based on the fact that people just happen to live above or control the small deposits of coal and oil and gas on which we depend. They'll be rich people in a solar world, but they won't be Koch brothers rich. And they won't have that degree of warping influence on our politics.

DAVIES: You've said many times that the question is, can we make change quickly enough? Give us a sense of the - what kind of time pressure we're under.

MCKIBBEN: The Intergovernmental Panel on Climate Change, our collection of scientists around the world, organized - sort of self-organized, put out their most important report to date last autumn. It said that to meet the targets set in Paris, we would need fundamental transformation underway by 2030. That is, in this country, we'd need to be - at least half our power coming from renewable sources. That's a really hard transition to make in 10 years. It requires a level of focus and attention that we've never come close to in the past on this issue. So it's going to take everything we've got to get it done.

DAVIES: If things don't happen in time, one of the things that people are talking about are big bioengineering solutions - I mean, like, you know, towers into the sky to pump gases or extract gases. And I can't even recall all of them. I've read books about them. How do you feel about those ideas?

MCKIBBEN: The most common of these is to say we'll fly a constant fleet of airplanes for the rest of time into the atmosphere, dumping sulfur there. And the sulfur will block some of the incoming solar radiation. The craziness of this is manifold. I mean, look. It would probably change the color of the sky to a nice milky white. We think that this mimics what happens with volcanoes when they put a lot of sulfur into the atmosphere and temporarily cool the planet.

But one of the things that often happens then is that the monsoon rains move off the subcontinent, which is an existential problem for a couple of billion people. More to the point, none of this does anything about the deadly twin of global warming, which is the rapid acidification of the oceans. We're an ocean planet. The fact that we're - have already made the oceans 30 percent more acidic would be, by itself, enough reason to get off fossil fuel, even if it didn't do a thing to the temperature. We don't need to pour sulfur into the atmosphere. We need to build a lot of windmills and solar panels.

DAVIES: One other thing - you know, we live in a time where civility is in short supply. And you've been trolled and harassed for your activism. What kinds of things have you faced?

MCKIBBEN: There was a long time when I didn't talk about any of it. But in the last few years, I've written some about the death threats, which have been a kind of standard-issue part of life for 30 years. We're reaching the point where people on the Internet were, you know, publishing my home address and talking about the specific methods they planned to use and so on and so forth. That kind of incivility - if that seems almost too weak a word for it - is part of our life now. But we can't let it be the thing that keeps us from doing our work.

All of this seems crazy to me, at some level. When I set out on this journey, I was a writer, not an activist. It never occurred to me that I was going to end up in jail or in handcuffs a bunch of times and things. And one shouldn't have to. I mean, in a rational world, when scientists issue a blunt warning that the worst thing in the world is happening, you would expect our leaders to go to work.

But the world in which we live in, apparently, people do have to do these kind of things. And people have to deal with a lot worse than I have to deal with. There's people around the world - environmentalists - who die every year in countries where this sort of thing has become routine.

DAVIES: Well, Bill McKibben, thanks so much for speaking with us again.

MCKIBBEN: Dave, what a pleasure. And thank you not just for this interview but for all your work every day. We really enjoy it.

DAVIES: Bill McKibben founded the environmental organization 350.org. His new book is "Falter: Has The Human Game Begun To Play Itself Out?" Coming up, rock critic Ken Tucker reviews a new album from the British band The Mekons. This is FRESH AIR.

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