A Radical Approach to Climate Change

cataclysmic events of the twentieth century. Torrential rain has mixed with volcanic ash to form a gray mud covering vast areas of the northern Philippines. The ash falls up to seven hundred kilometers from Mount Pinatubo. Nearly twenty million tons of sulfur dioxide were hurled into the stratosphere. The effects of the eruption were felt around the world. In the following fifteen months, average global temperature dropped by roughly one

degree fahrenheit. Why because the sulfur dioxide released by the volcano reflected back a fraction of the Sun's energy, preventing it from reaching the Earth. The notion that huge volcanos might affect the weather is actually an old one. Ben Franklin proposed that the severe winter of seventeen eighty three to eighty four was triggered by a massive eruption in

Iceland the previous summer. In nineteen sixty five, inspired by the volcano theory, science advisors to President Lyndon Johnson proposed develop helping technology to pump sulfur dioxide into the stratosphere to offset global warming, but the idea didn't go far because they had no good way to test it. Then, in nineteen ninety one, Mount Pinatubo ran a test for US. It seemed to confirm the hypothesis. The proposal started to

gain attention. Point is this, if the problem gets bad enough to do something about, well, don't you want to have something to do. The idea of that is to essentially mimic nature, which is what happens when a volcano blows. A big volcano blows. That's Stephen Dubner who touted the idea in his two thousand and eight book Super Freakonomics

as a quick fix for global warming. In politics, the idea attracted strange bedfellows, including former Republican Speaker of the House Knut Gingrich, Texas Republican and climate science skeptic Lamar Smith, and twenty twenty Democratic presidential candidate and Drew Yang. It even made it into the Netflix comedy show The Fix, where comedian d l hugely recommended blowing up a volcano

to save the world. So let's find some volcano in the middle of the ocean, far away from civilization and blow it the fu the idea, well, not blowing up volcanoes, but spreading sulfur particles to decreased solar radiation is a kind of climate intervention that some people call solar geoengineering. It's gotten enough traction that the US National Research Council organized a scientific committee to study it, and it's not

just theoretical. Some Harvard scientists are planning to launch an experimental balloon to start learning how to hack the planet. Today's big question, with the climate crisis becoming more and more desperate, should we get ready to alter the atmosphere of Planet Earth? Solar geoengineering? Can it protect us from climate change? Do we need it? And what could possibly go wrong? My name is Eric Lander. I'm a scientist

who works on ways to improve human health. I helped lead the Human Genome Project, and today I lead the Road Institute of MIT and Harvard. In the twenty first century, powerful technologies have been appearing at a breathtaking pace, related to the Internet, artificial intelligence, genetic engineering, and more. They have amazing potential upsides, but we can't ignore the risks

that come with them. The decisions aren't just up to scientists or politicians, whether we like it or not, we all of us are the stewards of a brave new planet.

This generation's choices will shape the future never before. Coming up on this episode of Brave New Planets Blocking the Sun, we'll talk to one of the leading proponents of the technology, so solar Gin My sharing ken with total confidence and this is not an overstatement for store temperatures to pre industrial We'll hear from two experts who weighed the benefits and risks for the National Academy of Sciences. I can

imagine this launching climate wars. Some third party might actually get to the point where the climate in their part of the world had become intolerable and they would unilaterally decide to modify the planet's climate without consulting with anyone, and we'll speak with the executive director of Sunrise, a movement of young people working to stop climate change, about whether it's time to consider what to do if else fails. I understand the desperation. I understand the urgency. I understand

that we need to kick everything into high gear. So stay with us Chapter one, Climate Crisis. To get up to speed about the climate crisis. I went down to Washington, d C. To visit one of the nation's leading scientists, someone I know well. So my name is Marsha McNutt. I am a marine geophysicist. As a geophysicist, what's the coolest thing you've been involved in? There are so many cool things that geophysicists get to do. I've been down to the bottom of the ocean to see volcanoes erupting

on the seafloor. I got to stand on the South Pole on the hundredth anniversary of Amonson's first conquest. I have been to outer Mongolia with nomadic tribesmen studying the birth of mountain belts. Chief physicists get to go a lot of very unusual places and do very wonderful things. Marsha McNutt has been a professor at MIT, head of the Monterey Bay Aquarium Research Institute, director of the US Geological Survey, and the editor in chief of Science, the

nation's leading scientific journal. Today, she's president of the US National Academy of Sciences, an institution created by Abraham Lincoln in eighteen sixty three to advise the US government. It prepares major reports on crucial scientific questions facing the country. I wanted to talk to Marsha McNutt because just before becoming president of the Academy in twenty and sixteen, she chaired the Academy's report on Climate intervention, and I also

talked to another of the authors of that report. My name is Ray Pierre Humbert. I'm the Highey Professor of Physics at the University of Oxford. I hadn't met Ray before. He's a dead ringer for Santa Claus. He's also an expert in planets, not just our own planet, but also exo planets, the thousands of planets outside our own solar system. My favorite planet is fifty five kancre E, which is so hot it has a permanent lava ocean on the dayside.

Where's that located. It's it's around the star fifty five kancres, which is not quite a visible star, but it is near the claw one of the clause of the scorpion scorpio. And that's your favorite planet. Well, let's say it's the one we're having the most fund with right now. I see it not the vacation on a It's not one of the vacation sites, unless you like lava beaches and so forth. So I talked with Marsha and Ray about

the current state of climate science. Now I shouldn't have to say this, but just in case you've been living on an exo planet or in a state of deep denial, there's no serious question that climate change is real or that it's largely due to excess carbon dioxide from burning fossil fuels causing a greenhouse effect. Here's the science in a nutshell. A greenhouse lets you grow greens and green Bay, Wisconsin in the middle of the winter because the glass

lets light pass through but holds the heat in. The thicker the glass, the better the heat retention. CO two does the same thing for the Earth. It lets sunlight pass but retains much of the resulting heat. CO two has been increasing sharply over the past century, two levels unprecedented in human history, and as a result, the Earth is getting hotter. The last six years ranks of the

six hottest years in recorded history. There is a lot more attention to global warming amongst the public and the press, and amongst politicians, now that we are starting to see some of the effects. What we've seen with just about a degree of warming is nothing compared to what you

get with the second degree of warming. Swaths of Puerto Rico underwater roads turned through raging rivers, millions of people affected by devastating floods across South Asia, his historic fires devastating Australia, more than one hundred wildfires burning in the Arctic. Firefighters in California continuing to battle some dangerous, fast moving wildfires, five of the six largest infernos in state history, because of the release of CO two into the atmosphere from

the burning of fossil fuels. Primarily, we are entering basically an unknown regime of rapidly changing climate. It is very difficult for anyone looking at the data to say with any confidence that in this future that we are entering will continue to be dousive for human habitation. Once you enter that zone, you basically can't back up. The dye has already cast, and every projection shows that we have at most decades to act. What are the sort of events we expect to happen as we have more and

more SEO two in the atmosphere? What do we see happening now and what do we imagine happening in the future. So what we see happening now are things like ice sheet smelting, sea level rising, more energy in the atmospheric system, which leads to more storminess, higher amounts of rainfall, stronger hurricanes. Areas of the country that used to be pleasant to live in now becoming uninhabitable because of storm surge and high tides. We're seeing death of coral reefs because the

ocean's too warm for them. Some of the things that are more complicated but likely to be far more damaging are the longer droughts, the inner actions between ecosystems, things like the bloom and plankton coming earlier in the spring when the animals that need to feed on them haven't yet returned from their migration, So you basically get animals dying of starvation. Chapter two the wet bulb temperature. When scientists describe global warming, they usually talk about average temperature rise.

For example, take the twenty sixteen Paris Climate Agreement. That's the UN agreements supported by one hundred and ninety four countries but sadly no longer including the United States. It aims to keep the average global temperatureize below two degrees celsius. The problem is that an average temperature rise of two degrees celsius sounds puny, even if you convert it to roughly four degrees fahrenheit. After all, temperatures can fluctuate by

twenty degrees fahrenheit over the course of a day. What's the big deal? I worry that we as scientists have perhaps done a disservice to climate change by talking about average changes because the average doesn't sound so bad. But when you talk about how the extremes are likely to change, that is when it gets very scary. One of the aspects of climate change that scares me the most is if instead you measure climate change by how many days in a ser location is the temperature likely to exceed

the wet bulb temperature? What's the wet bulb temperature? It's basically the difference between life and death. Your body is always generating heat, and to keep your body at a constant temperature, you need to radiate away the excess heat. If you can't, you'll die. On a cool day, it's no problem, your skin can lose heat directly to the air. But on a hot summer day, you need to sweat

so the evaporation carries away the heat. Now, if the temperature and the humidity get too high, a person literally can't sweat enough to cool themselves. What's the limit. Well, at fifty percent humidity, you can't make it much past one hundred and twelve degrees in the shade. So unless that person can get to someplace that's air conditioned, they

will literally overheat and suffer heat stroke. There are many places on this planet right now in India, Southeast Asia, Africa where the number of days that are exceeding the wet bulb temperature are going up dramatically every summer. We're even seeing life threatening temperatures across temperate zones in Europe, with record highs recorded in Germany, Netherlands, Britain and France, with the ladder hitting roughly one hundred and fifteen degrees fahrenheit.

So a better way to think about the effective climate change might be the number of days that a region becomes uninhabitable outdoors. If you go from say one degree of warming to two degrees of warming, a lot of the damages scale linearly. If you used to have, say something like thirty days of life threatening heat waves in some place, we go to something like sixty days when you go two degrees. What would happen if we blow past two degrees celsius, it's more like a global rise

of four degrees celsius. If you get to four or five degrees global mean warming, then you get to the situation where perhaps half of the earth becomes uninhabitable outdoors for mammals. Then air conditioning becomes not a matter of comfort but a matter of life support. It's like living in a space station and a power failure becomes not just a matter of inconvenience but megadeath. Of course, most people on Earth don't have access to homes with air conditioning.

It's these people who will suffer. And then you also have to think about all the animals that are not going to be living in air conditioning. What happens to elephants, what happens to cattle. It's a very different world. Unfortunately, we're not making much progress on reducing CO two emissions by almost all scientific accounts. If we don't drastically change our fossil fuel consumption, we're going to blow past the

target of two degrees in the Paris Agreement. The problem is it's really hard and really slow to change the world's energy systems. To move to renewables requires electrifying your energy system. That's really the only realistic way to do it. Electrifying the system requires building transmission lines. My homes in California, it can take three years just to permit a new transmission line. Replacing power plants takes even longer since they're

designed to last for decades. Power grids generally evolve over a forty year time scale. So this is why many scientists and many policymakers are concerned about taking an infrastructure system that has a forty year renewal rate and trying to respond to a problem that needs immediate action. Here's where the volcano strategy comes in. We've already tampered with our atmosphere and we're starting to feel the consequences. Why not tamper some more to prevent some of the warming,

saving lives and curbing suffering. That's the idea behind this type of climate intervention. Is it time to start experimenting with the technology? Chapter three, Tiny space Mirrors. I arranged to speak with Professor David Keith. He's one of the leading proponents of solar geo engineering research and he's aiming to run a small scale test. David agreed to bicycle down from Harvard to the other end of Cambridge where

I work at the Broad Institute. So solar geo my sharing ken with total confidence, and this is not an overstatement for store temperatures to pre industrial Long before David started thinking about solar gew engineering, his scientific career had an unusual start. His first job was as a research

assistance in the Arctic. The year I was there, we were really working on walruses and we were trying to learn how to identify them by their calls, and then we had to brand them with cattle brands that we bought in Albertic and my job as the young guy, was to carry the brands. That was the light part and the propane tank and the kind of flamethory thing that you needed to heat have the brands. I'd done way more big outside time than most people, so probably

more than a thousand kilometers of kind of Arctic ski trips, expeditions. Whatever. Would you call yourself an environmentalist in this topic? This is such a big fight, you know, I feel like that's for other people to judge. But I'd say I've been to Earth First rallies and I've done our actions, and yeah, I think the short answer it would be yeah. He began studying global warming when he arrived at M

team the nineteen eighties. I stumbled into this really cool group of students in between Harvard and MIT grad students who were working on climate change, both the science and public policy in an interdictminary way. Today, David focuses on solar geoengineering. He's mostly focused on stratospheric geoengineering, which is what we've been talking about, mimicking the behavior of a

volcano by spraying reflective particles into the stratosphere. But there's actually several different ways of changing the Earth's solar radiation. There's the idea of brightening a certain kind of marine boundary there cloud Brighter clouds would reflect more sunlight. There's the idea of thinning a kind of serious cloud by adding silver eyedide or something like that. Whispy or clouds

would trap less of the Sun's heat. And then there's space based technologies idea you could build big orbiting mirrors or what have you. To make a difference, space mirrors would need to be huge with a surface area though about the size of Greenland. It wouldn't be cheap get them into orbit. I think if you think in the next decades, I think the idea of space based stuff

is ridiculous. But if you're thinking about this is something a humans do over a century or century and a half, I don't think it's crazy to think that we might do space space things. For now, though, the best approach would be stratospheric intervention, putting reflective particles into the atmosphere. You can think of them as tiny space mirrors just to the lower altitude. Planes would fly around the stratosphere, springing plumes of sulfur dioxide or similar chemicals. It would

be surprisingly cost effective. The cost to kind of begin a program that's putting material quantities of staff in the stratosphere is probably just a few billion dollars the kind of climate damages we're talking about a global basis or of order a trillion a year. So the idea that a few countries spend a few billion a year, that's a small enough number. They don't think that cost is going to be the direct driver. A few billion dollars to clean up a trillion dollar mess sounds like a

pretty good deal, at least on paper. What could possibly go wrong? Chapter four? What could possibly go wrong? When the National Research Council scientists set down to write a report on solar geo engineering, the first thing they realized was that calling the technology solar geo engineering might be seriously misleading. I never liked the term geo engineering myself, because engineering is term we generally apply to precise management

or design to control systems that we actually understand. But what is generally called geo engineering is something that is really hard to try out, hard to resolve. The main questions about this is basically throwing up these particles into the stratosphere at the whim of the jet stream. They go where they will. It's not like a house with thermostats in every room, where you can turn this room a little cooler and maybe this one not so cool, and turn this one off because no one really needs

it in this room. So we preferred the term albedo modification, even though it sounds kind of wonky. Albedo is the scientific term for the reflectivity of a planet. Unfortunately, albedo modification wouldn't mean anything to the general public. The other extreme,

some people use the term hacking the planet. There's a lot of sort of techno optimism involved in the people that are doing research on this, which is very similar to the sense of pride, where you're hacking a system and it is a sort of cool thing to contemplate, And if we didn't have to live on the planet, I'd be really interested in it myself. But it is dealing with the only home that we have and has potentially really very serious consequences. Ultimately, the scientists settled on

the neutral term climate intervention. I like the climate intervention because just like with interventions, and say a person who has a drug problem or whatever, you're not guaranteed to achieve the outcome that you want. You're having an intervention because you know something is wrong, but you just can't be sure that you're not going to actually make the situation worse, but you may be so desperate that you

really need to do something. As the scientists dug into the problem, they recognize that the perfect climate intervention would simply be to dim the sun by one or two percent. Unfortunately, though, the Sun doesn't have a dimmer switch, and using particles to block the Sun's rays isn't quite the same thing. You can control the average global temperature, but the impact across the globe may be very uneven. If you put aerosols up in the stratosphere, tiny little particles in the stratosphere,

they don't just sit there where you put them. They get blown around by the stratospheric winds, They take up water, and they get bigger. Bigger particles have different reflective properties than smaller particles. They tend to get bunched up near the poles eventually and fall out the poles. You don't necessarily get an equal distribution between the northern hemisphere and the southern hemisphere. That might have serious consequences for the

Earth's climate. Modeling has shown that if the aerosols were to preferentially bunch up in one hemisphere, that actually shifts the tropical rainfall patterns into the opposite hemisphere, so you would actually create potentially serious droughts. That's one example of the sort of thing that could go wrong inadvertently. So to put it in the simplest terms, you're saying, we could put up aerosols and end up completely surprised by

the winners and losers in the climate effects of that. Right, So, it's hard to guess in advance how particles will distribute in the stratosphere. They might cool certain areas of the globe but leave others vulnerable to droughts and heat waves. Moreover, it's hard to run a local field test. We can't just say, okay, we're gonna albedo modify over El Paso, Texas, and does El Paso get cooler? And what happens till El Paso's rainfall and are there any negative effects of

sulfur particles falling out of the air or anything. You can't do that because once I put it up over El Paso, how long before it distributes around the world. So most of these injections have to be done near the equator because that's the best place for distribution, and they very quickly get into these stratospheric currents that distribute them, and within two years it's all dissipated, it's all gone, It all filters out, So you would have to reinject

every year to two years. So one thing you can't say at least is if you're willing to tolerate a global experiment, at least it would go away. Let's pull that thread for a second. Suppose somebody were to do a global experiment for a couple of years. Now here's the issue with doing an experiment, a global experiment on albito modification. We have no idea how to attribute whatever might happen during those two years to the experiment itself

versus natural variability in storminess, droughts, floods, whatever. And you can be sure anyone who might have been impacted during that period by a hurricane, a drought, a flood would say, Bingo, you did this experiment and I got flooded out of my house, or I had a hurricane take out my barn, or I had a drought that wiped out my herd of cattle. You owe me. There'd be lawsuits all over the place. There would be lawsuits all over the place, And who's going to indemnify the person who does the

experiment against the lawsuits. Do you think there's any insurance company that wants to take on that policy? Chapter five The Big Balloon. Despite the challenges, David Keith wants to try an experiment, a very small experiment. He's working with a team at Harvard on a project called scopex. So Scopex is about trying to improve our models of the way stratospheric aerosols and chemistry work in little ways that are relevant for improving understanding of the risks and efficacy

of solar geno engineering. Keith and his colleagues want to send the balloon carrying particles high into the atmosphere, puff them out, and see how they disperse and reflect sunlight. How big is this balloon? Just give me a picture. Balloons are like twenty meters diameter, rough sixty foot wide balloons going up. And what's attached to the balloon we're

building the balloon gondola still what you call it. The gondola has two little propellers that are more to kind of move it around slowly, and it has our data system. It has the batteries to run, It has the thing that generates the particles it has a particle sensor to measure the particle size distribution, and the whole thing is on a winch, so it can winch itself up and down with alter to the balloon, so the balloon will spray particles and then right around measuring how they disperse.

The amount of material the team is going to release is actually tiny, a kilogram or something, which for the sake of argument, that turns out to be the bound of sulfur that a commercial aircraft you would normally fly, and releases it about a minute's flight. While it's physical cargo is tiny, the balloon also carries with it a lot of questions about regulations, scientific knowledge, symbolic value, and

possible political misuse. While there's no serious scientific case that spraying a kilogram of particles can cause any physical harm, some people still think it's very dangerous. There's a group of people, and by high quality pulling, we know this group of people is like a third of Americans who believe that the government is already spraying toxic chemicals from

airplanes for mass murder or climateguzation or something. And so those people have conflated that with some of the scientific work on solar gena sharing, so when they google around or there's lots of sites that will have me as a mass murder. I once got a voicemail. My favorite one that my kids enjoyed a lot, was a voicemail that said that I was ten million times more evil than Hitler and Stalin. And then it's not quite clear if the gentleman is saying that it's combined or separately.

But it's not just conspiracy theorists. Even some of David Keith's friends, like Ray pr Humbard or opposed to scopex. It is actually one of the joys of science that, at least among scientists, you can have very vehement professional disagreements and still remain on good terms. What's really funny is, at least from my perspective, I have huge respect for Ray, both scientifically actually as a human. There's an article, the most recent article he wrote, which is actually the most

personal and attacking me. It was like attacking the Harvard program. I forget exactly what it said, but it was like pretty direct, you know, both smoke and barrels aimed my way. That was published just a few weeks after I had a wonderful dinner with him and his wife actually visited him in Cambridge, Oxford, and we talked about exoplants, and we talked about American politics, and we mostly actually avoided

talking about this topic. We know we disagree. I don't imagine that David would pay any attention to what advice I gave him, but I would advise him to just drop scopex. Ray has multiple objections. On the one hand, the experiment is too small. Releasing a few particles won't teach us anything important about the large scale planetary processes that would matter most. I still lean towards calling them stunts and that while they have some scientific payback, they

don't really address the biggest questions we have. You can't do that with just a puff experiment. If you really want to resolve some of the questions, that are going to be a maker break thing for what would happen if you deployed Albiedo modification. There are a hundred other things that are more important scientifically. On the other hand, Ray is concerned that the experiment will open the door to ever larger solar geo engineering efforts before there are

any rules in place. It's the risk that by doing a small experiment that crosses a red line. You're opening the door to escalation. If you can do a small experiment, well, next year someone's going to do a bigger experiment. It represents the thin edge of the wedge. What can of worms are are you opening? But Ray's biggest concern is more fundamental. Solar geo engineering is wildly, howlingly barking mad, and no research developments have changed my opinion. One Iota,

Chapter six, The Sword of Damocles. What makes rayper Humbard call solar geo engineering wildly, howlingly barking mad. It boils down to two things. First, it doesn't solve the real problem. As long as we continue to emit CO two, it continues to accumulate in the atmosphere, much of it remains for tens of thousands of years, and the greenhouse effect keeps increasing. Climate intervention just masks the problem by reflecting away sunlight while we keep pumping vast amounts of CO

two into the air. The second problem is solar geoengineering could create a sort of time bomb. My biggest worry, in fact, the worry that underpins all my other worries about the possibility of deploying albedo modification stems from the mismatching time scales. The mismatching time scales is this, while much of the CO two sticks around for tens of thousands of years, the sulfur particles that would be used for geoengineering, they disappear very quickly. They need to be

replaced every couple of years. You're committee the entire future of humanity to doing this essentially forever. When have we ever saddled the next one hundred thousand years of civilization? If within obligation to do something without fail each and every year forever, Essentially, there's no precedent in human history if you then stop. If you stop because there's a global war, there's a global depression, or disputes over what the effect of this is, or you find some horrible

side effect that you just can't bear. If you stop doing this lbedam modification, then within about ten years you have nearly the full effect of all the pent up warming from that carbon dioxide in the atmosphere. That's what we call termination shock. Everybody on the planet living under the sort of damocles, knowing it could fall at any minute, exactly how much pent up warming what depends on how much CO two we've allowed to accumulate. A rapid warming

of two degrees celsius would be bad enough. Rise of four degrees see within a decade, making large swaths of the planet uninhabitable outdoors most of the year. That would be catastrophic. I asked Ray if he thought solar geo engineering would ever make sense. The only scenario is if you actually had already committed to getting to zero carbon dioxide emissions in a reasonably short window of time, or if you had developed technology for removing carbon dioxide from

the atmosphere. In other words, if we had largely solved the problem and only had to buy a little bit of time. Unfortunately, we're not on target to get to zero net emissions, and we're very far from having affordable technologies for carbon capture from the atmosphere. Chapter seven, Climate Wars. If the climate crisis continues to deepen, who would decide

whether and when to deploy solar jew engineering? Would United Nations try to forge a global consensus, or because it's not so expensive, might some nations just try to do it on their own. I can imagine some country could just start deploying Albita modification just because of their own perceived self interest. Imagine a human nation that is seeing its elderly people dying from heatstroke. They may think putting a bunch of particles up in the air as a

pretty simple solution to it. And if that means that the Canadian wheat harvest fails, well that's their problem. I can imagine that conflicts that could arise when nations start tinkering with the composition of the stratosphere. I can also imagine this launching climate wars because there are quite easy countermeasures. The kinds of air craft that would be actually spewing out sulfur dioxide into the stratosphere. They're slow moving, they're

easy to target by fairly simple missiles. There are other kinds of countermeasures you could think of. For instance, if other countries used geoengineering to slow climate change, but Russia preferred to let the Earth keep warming because it would open the Arctic Ocean year round, Russia could interfere. All they'd have to do would be to increase their coal burning,

increase the CO two to offset the Abito modification. Russia could actually even do more harmful things, releasing methane into the atmosphere, they could start manufacturing sulfur hexafluoride, which is an incredibly potent, long live greenhouse gas. It turns out that the fear that countries might start acting on their own was the initial inspiration for the National Research Council report.

The intelligence community was concerned some third party might actually get to the point where the climate in their part of the world had become intolerable and they would unilaterally decide to modify the planet's climate without consulting with anyone. Some argue that solar geoengineering is basically ungovernable. If one country wants the world slightly warmer and another needs it cooler, how could we get a global consensus about who sets

the thermostat right now? There is no treaty, There is no international agreement. There is no government structure that actually prevents anyone from intervening in the atmosphere or the stratosphere to perform some kind of albedo modification. The Academy has a study underway right now that is focusing on the governance issue, and hopefully they will come up with some good ideas of how to take this forward. Chapter eight Sunrise. Given all the problems with solar geo engineering. Why are

scientists even considering it? The reason is they're beginning to feel pretty desperate. While the Paris Climate Treaty aims to keep global warming to two degrees c on, our current trajectory will blow past that target and may barrel toward catastrophic increases. Some feel we better be ready with a break glass in case of emergency solution, but a solving climate change really hopeless. A lot of young people have been rising up lately to demand action. They think the

answer will require not just science but political pressure. Seventeen year old Swedish activists Greta Thunberg recently gained international attention for her call for a global climate strike and her demands for policy change at the United Nations. People are suffering, people are dying. Entire ecosystems are collapsing. We are in the beginning of a mass extinction, and all you can talk about is the money and fairy tales of eaton

of economic growth. How dare you? In the US, a youth led environmental movement has been organizing to pressure politicians through sit ins, songs, and communal action. I decided to talk to one of the leaders and what's become a

global movement. My name is Marsheni Prakash. I am one of the co founders of and currently serving as the executive director for Sunrise Movement, which is organizing tens of thousands of people, predominantly young people across this nation to make climate action a priority in our nation for the first time. So tell me how you got to that point, Like, what was your path? I am the child of two

South Indian immigrants. India as a place that is being ravished by the climate crisis, whether it's through drought and water wars, or farmers committing suicide by the tens of thousands, or climate fueled floods worsening and impacting people. And I remember it was like the fall of twenty fifteen when a series of really horrific floods hit my families from

in southern India. And I remember roads and sidewalks that I had walked on, that my dad and had grown up on, just covered in feet of water and seeing dead bodies and people walking chest deep in water for miles to sanctuary. And it was this major moment of reckoning, of realizing that the climate crisis was here there were

people dying as a result of it. It wasn't an issue thirty forty fifty years in the future, and the movements that we had in that moment were not growing or weren't as powerful as we needed them to be. To address this crisis, Varshini joined a group of young

climate activists who wanted to drive big change. We embarked on this process for almost a year of strategic planning, of research, of study, of an assessment of the field, studying things like the civil rights movement, queer movements, women's suffrage, Vietnam War era movements, and then contemporary movements as well, like the movement for Black Lives, Occupy Wall Street, others, to see how do people make these grand societal transformations that we need to make to stop climate change, and

how do we emulate that. Out of this work came Sunrise Movement, which aims to bring together millions of people, especially young people. As you may have heard, they've proposed a program called the Green New Deal. One important element of the program is funding innovation to drive down the cost of renewables to the point where they're cheaper than fossil fuels. But the aims of the Green New Deal

are far more ambitious. It can be thought of as a decade long economic mobilization really to stop climate change at a scale not seen since World War Two. Everything from stopping climate change to creating tens of millions of good, high paying jobs, virtually eliminating poverty in the process. Everything from addressing agriculture systems to industry, to power generation and land use, forestry, everything under the sun that we would

need to deploy to address the crisis. It won't be just one piece of legislation, and it was the same way with a New Deal. It wasn't There wasn't a New Deal bill. There were hundreds of bills and projects that FDR and others implemented. They were really embracing this ethos of experimentation, of doing whatever it takes to get Americans out of the Great Depression and put money back in the pockets of working people. The Green New Deal resolution is more of a framework than a specific piece

of legislation at this point. Still, the idea has prompted a range of concerns. Climate change deniers belittle it. They want to take your pickup truck, they want to rebuild your home, they want to take away your hamburgers. This is what Stalin dreamed about but never achieved. Many scientists and economists view achieving carbon neutrality within ten years as a pipe dream given the slow rate at which power

plants are replaced. Others think it's trying to do too much solve climate change, poverty, and racial injustice all at the same time. But maybe the Sunrisers are onto something very important in the way they're building a coalition packaging them as one thing. This sounds sort of counterintuitive to some people, but it actually makes it more popular. The parts of the Green New Deal that are the most popular are the parts around job creation, are the investments

and sustainable agriculture and renewable energy technology for shiny. Contrasted, the Sunrise movements approach to previous climate change legislation efforts like the Waxman Marquee Bill in two thousand and nine, the last forty years of focusing on just like a singular tax or a singular cap and trade model, or something that people cannot understand as making basic improvements to their lives. That's why a lot of the reason why Waxman Marquis failed in the Senate ten years ago, because

there wasn't the public will and the public support. She talked to Senator Marky, who sponsored both the two thousand and nine bill and now the Green New Deal Resolution. I asked him, what is the major difference that you are seeing in twenty nineteen versus two thousand and nine, and he said, the number one difference, and what we need so badly is that we actually have an army of people out there pushing for these solutions. I asked

Marsha McNutt what she thought about Sunrise movement. I love it. I think it's critical. I mean, if it's not going to be that generation, then who they're the ones that are going to still be alive in twenty fifty. It's not going to be me, and it's going to be their children that are going to be alive in twenty one hundred that are going to be inheriting this parched earth. It's incredibly important that they stand up and say no, this is not their trajectory that I want for the planet.

And when politicians vote with a two year time horizon in their mind, or if they vote special interest groups who are looking only at their corporation one year ROI, that is absolutely criminal. So What would you say to the people in the Sunrise movement? What encouragement or message would you say to them? I would say, they are just like the people who stood up to the Vietnam War and every other injustice. You know, this is an

injustice to all of humanity. So, after talking with Varsheni about Sunrise Movement, I asked her whether she and her fellow activists thought solar geo engineering might be an important tool in addressing climate change. She was unconvinced, regarding the technology as a distraction from solving the real problem. If the issue is decarbonizing and the long term problem is taking carbon out of the atmosphere, things like geo engineering don't even do that. But and so, don't get me wrong.

I understand the desperation, I understand the urgency. I understand that we need to kick everything into high gear. But I think we are putting carbon into the atmosphere. Perhaps the easiest fix that we have is to stop putting carbon into the atmosphere. Chapter nine, The Moral Hazard. I understand why climate change activists want to stay laser focused on decarbonizing the world's energy supply, But at the same time, is there any harm in also having climate intervention as

a backup. Unfortunately, the answer is there might well be. Some people worry that pursuing solar geo engineering and parallel might actually make it harder to get the world to solve climate change. Humans tend to address problems only when they feel the consequences, such as heat waves, wildfires, floods, and hurricanes. If blocking the sun decreases natural disasters caused by global warming, will we become complacent about solving the

real problem. It's like taking a painkiller instead of actually having the cancer taken out. Eliminating one of the symptoms of carbon dioxide emission, which is the planet getting warmer, makes it easier to ignore the root cause of the problem just continue emitting. This is what economists call the moral hazard problem, the idea of the people who have

insurance against disasters aren't as careful about avoiding risks. For example, because the government provides flood insurance for homes on floodplains, homeowners are more willing to keep rebuilding their flooded homes on the same sites. But David Keith is worried about something even more insidious that the mere prospect of solar jew engineering will be used as a political weapon to

deny the need to act on climate change. At the beginning of this episode, I noted that some of the greatest enthusiasm and congress for solar jew engineering has come from climate change deniers. That's certainly no accident. People are terrified that if these ideas get out more in the big world, that they will be seized upon by opponents of climate action, by oil companies, by people who want

to walk emission scots. Those people will claim falsely that solo genissioning means we don't need to kind emissions, or that it may mean we don't have kind emissions, and they'll use that in the bruising political fight over emission scots. That is the underlying, I think biggest fear, and sure, of course it's a complete lygim I fear. I'm terrified

about it. The certainty that they will try and use it as an argument is there, but that doesn't mean that necessarily humanity will do less emission scots, and in the end, those of us who want emission scouts just have to win on the merits. Although David Keith is certain his work will be misused by some politicians, he believes it's essential to do the research. I still think that that fear is not a reason not to know more.

You may think, or summon your audience to this podcast, may think the solo Regeniastoni is a terrible idea and never should be done. Others may think it really could be part of the way we manage climate change. But let me let you all out there and podcast land in on a big secret. We're not deciding now whether or not this happens. We're decide whether we give the next generation realistic information. If we keep the taboo going,

then we'll hand them basically no information. So sometime the next decades, some government, maybe the Chinese government after their monsoon fails, maybe the US government after a massive Category five his New York, maybe the Indonesian government after a big heatwave that kills a quarter million. Some government is going to seriously consider this. And my view is that we'd be better to give them lots of knowledge before

they consider it. But Raypierre Humbard doesn't buy it. So David likes to make the case that if we don't do these experiments, will just be giving the gift of ignorance to the future. But sometimes the gift of ignorance is a precious gift, and so we have to decide first whether this is a case where the gift of

ignorance is precious or a burden. I think if it had been possible to actually give the gift of ignorance about horrible things like nerve gas, if we're dingle to have the gift of ignorance about building hydrogen bombs, whether or not that would have been feasible or not, that would have been a nice kind of ignorance to have. And again I'm not saying that necessarily albedo modification is in the same category as these things, but someone has to make that judgment, and it has to be made

by civil society in some way. So where do you draw the line. I think that it would be impractical to have any form of governments that forbid computer experimentation. But when it comes to stuff kit gear, either a lab experiment, but especially outdoor experimentation, actually stuffing things into the atmosphere, even on a small scale, there is a kind of a clear line there, and so that's where I think there needs to be some kind of discussion.

Is this a red line worth crossing? Is the scientific payback enough to actually justify crossing this red line conclusion. Choose your planet. So there you have it, solar geoengineering. It could cool the planet at least on average. It might buy time and mitigate suffering, but its precise impacts would be uneven and unpredictable, and it's very hard to test. There could be big winners and losers. It could even

trigger climate wars. If we choose climate intervention, we might end up addictive for thousands of years, threatened with rapid, massive temperature increases if we ever stopped. If we don't consider climate intervention, we might find ourselves without options as

temperatures keep rising in the decades ahead. Should we start experimenting now so that we'll know enough to be ready or is it a distraction or even worse, a gift to climate change deniers who'll use the prospect of solar geo engineering to keep us from solving the real problem. So the question is what can you do a lot? It turns out you don't have to be an expert, and you don't have to do it alone. If enough

people get engaged together, we will make wise choices. Invite friends over for dinner and debate about what we should do, or organize a conversation for a book club or a faith group, or a campus event online of course for now in person, when it's safe. And if you hate having to consider these choices about solar geo engineering, then join a group to help stop climate change before it's too late. You can find lots of resources and ideas at our website Brave New Planet dot org. It's time

to choose our planet. The future is up to us, and my kids still debate when I'm their dad, is more evil than Hitler and Stalin or Hitler and Stalin combined. That's good to know what the family debates. That's fascinating. Brave New Planet is a co production of the Broad Institute of MT and Harvard Pushkin Industries in the Boston Globe,

with support from the Alfred P. Sloan Foundation. Our show is produced by Rebecca Lee Douglas with Mary Doo theme song composed by Ned Porter, mastering and sound designed by James Garver, fact checking by Joseph Fridman, and a Stitt and Enchant special Thanks to Christine Heenan and Rachel Roberts at Clarendon Communications. To Lee McGuire, Kristen Zarelli and Justine Levin Allerhand at the Broad, to mil Lobell and Heather Faine at Pushkin, and to Eli and Edy Brode who

made the Broad Institute possible. This is brave new planet. I'm Eric Lander. Two