Making Sense with Sam Harris - #95 — What You Need to Know About Climate Change

Episode Date: September 5, 2017

Sam Harris speaks with Joseph Romm about how the climate is changing and how we know that human behavior is the primary cause. They discuss why small changes in temperature matter so much, the threats of sea-level rise and desertification, the best and worst case scenarios, the Paris Climate Agreement, the politics surrounding climate science, and many other topics. If the Making Sense podcast logo in your player is BLACK, you can SUBSCRIBE to gain access to all full-length episodes at samharris.org/subscribe.

Thank you. of the Making Sense podcast, you'll need to subscribe at samharris.org. There you'll find our private RSS feed to add to your favorite podcatcher, along with other subscriber-only content. We don't run ads on the podcast, and therefore it's made possible entirely through the support of our subscribers. So if you enjoy what we're doing here, please consider becoming one. My guest today is Joseph Rome. Joe is one of the country's most influential communicators on climate science and solutions. He was chief science advisor for the show Years of Living Dangerously, which won the 2014 Emmy Award for Outstanding Nonfiction Series.

He is the founding editor of Climate Progress, which Tom Friedman of the New York Times called the indispensable blog. In 2009, Time named him one of the heroes of the environment, and Rolling Stone put him on its list of 100 people who are, quote, reinventing America. Rome was acting Assistant Secretary of Energy in 1997, and he's a fellow at American Progress and holds a PhD in physics from MIT. And perhaps most relevant, he is the author of Climate Change, What Everyone Needs to Know, put out by Oxford University Press. And it is a very handy, accessible, comprehensive book that is organized in Q&A format. So every question you have ever had or heard posed, skeptical or otherwise about climate change, seems to be answered in this book. And Joe and I get into many of the details. We

talk about how we know the climate is changing and how we know that human behavior is the primary cause. We talk about feedback mechanisms that increase the problem of global warming and why small changes in temperature matter so much. We talk about the threats of sea level rise and desertification and the best and worst case scenarios given where we currently are. We talk about the much maligned Paris Climate Agreement and the politics surrounding climate science. And now, without further delay, I bring you Joe Rome. I am here with Joe Rome. Joe, thanks for coming on the podcast. Thanks for having me, Stan.

We're going to talk about climate change, which, as you know, is a big and important topic. And we will talk about what we know about it, what we don't know about it, and I suppose what many people refuse to know about it. But first, before we jump in, can you describe your background scientifically and in policy circles and just the work you've done on this issue? Sure. Well, I have a PhD in physics from IT, and I spent a year on Capitol Hill as a congressional science fellow. And then I went to work at the Rockefeller Foundation for a couple of years, looking at issues like the environment and national security and energy. And I worked with Amory Lovins for a couple of years, the father of energy efficiency, really a great guy.

And then five years at the U.S. Department of Energy during the Clinton administration, where I ended up acting assistant secretary for energy efficiency and renewable energy, which is the billion dollar office that does all the clean energy research, development, demonstration programs for the federal government. And then I left to do a lot of consulting with companies on how to reduce greenhouse gas emissions and how to use efficiency and renewables. And then August 29, 2005, Hurricane Katrina destroyed my brother's home. In 2009, 2005, Hurricane Katrina destroyed my brother's home.

He lives in Pasquistian, Mississippi. And a mile inland, there was a 20-foot storm surge. And the inside of the house looked like a washing machine. He asked me if he should rebuild his home. And I started talking to climate scientists and hurricane experts and reading the literature and going to conferences and that's when I realized that two things climate change was a lot more dire than I realized and that scientists weren't doing a very good job of communicating it. And since I had been raised by newspaper people, my father was a newspaper editor, I decided to stop doing clean energy consulting and just do

writing and communications on climate change. And I was able to get a position at the Center for American Progress, which had recently started and launched its Think Progress website, which is one of the most widely read progressive news websites in the world. And that was about 11 years ago. 11 years ago next week, I launched climateprogress.org, I launched climateprogress.org, which grew over time into a, you know, we now have a staff of five or six reporters. It's part of the larger ThinkProgress enterprise. If you go to ThinkProgress, you'll see articles by me and other people on clean energy and climate change. It's probably the most widely read climate website in the world.

And that's what I've been doing for 11 years. Also worked with the Years of Living Dangerously TV series. 11 years. I also worked with the Years of Living Dangerously TV series. Some of you may have seen on Showtime a few years ago or last year on National Geographic Channel. That's the James Cameron, Arnold Schwarzenegger series, Emmy-winning series that documents what's going on on climate change, what the solutions are. And so that's what I've been doing. You know, I'm very fortunate to, you know, be able to keep track of climate change and clean energy and write about it and speak about it.

Yeah. And you've written this very lucid book that's right on point titled Climate Change, What Everyone Needs to Know, published by Oxford University Press, which is not actually known for publishing propaganda. And if I'm not mistaken, your PhD in physics from MIT was not focused in some totally unrelated area. Didn't you have some focus on oceanography? It did focus on oceanography. Yeah, I was fortunate. I was able to do my PhD thesis with a man named Costas Zippes, who, back in the day, wrote a great number of scientific scientific american pieces particularly on arms control issues and he let me allowed me to do my thesis research at the scripps institution of oceanography uh with walter monk one of the

world's greatest oceanographers and uh actually did my thesis wasn't on climate change at all, but the thesis itself was an analysis of data from the Greenland Sea. And, you know, just being at Scripps and attending seminars by some of the world's greatest oceanographers, you know, I couldn't help but also learn at the time, this was the mid-1980s, before a lot of people were talking about climate change, they were talking about climate change. So that was a true education. Right, right. So before we jump into the details here, I should say that my goal in this conversation is to dispel the most consequential forms of confusion on this topic. And so I went out on Twitter when I knew we were going to do this interview, and I announced that I'd be doing

a podcast on climate change, and I asked people to post questions, and I got over a thousand responses. So there's no shortage of questions here. But let's start with the basic picture of what's going on. And I want to get into the weeds, but I don't want us to assume that people know much of anything about this issue, because despite its enormous importance, most people, certainly many people, don't. So first, what is the difference between climate and weather? Well, climate, they say, is what you expect and weather is what you get. So weather is highly variable day to day. Is it going to be cloudy?

Is it going to rain? Is it going to be a very hot day? Is it going to be a coolish day? That's the weather. But of course, on a given day, whether it's warm or cold is relative to what the underlying climate is. A hot day in the summer is obviously quite different than a hot day in the winter. So weather forecasting is obviously tricky, hard to do more than a week, 10 days in advance.

But climate is the statistical aggregation of all the weather. So climate tells you it's going to be warmer in the summer. Climate tells you the Greenland is going to be colder than the Sahara Desert, and the Sahara Desert is going to be drier. So the long-term trends in your local climate are very slow moving. And one of the points that I make in the book and on the website is that, you know, since we came out of the last ice age 11,000 years ago, the Earth's climate has been very stable. And the temperature has really varied, you know, over maybe half a degree Fahrenheit plus or minus. And that stable climate is what allowed people to settle in cities. You know, they had reliable, you know, the weather wasn't constantly changing. They knew what the rainfall would be. They knew what sea levels would be.

People, therefore, could have, you know, large scale agriculture, and that led to cities, and that has sustained now a population of over 8 billion people. But because we have been pouring vast amounts of heat-trapping greenhouse gases into the atmosphere, we have seen a rapid rise in temperature, particularly over the last century or so. And in fact, the temperature of the earth driven by greenhouse gases, driven by burning fossil fuels, coal, oil, and gas, and releasing carbon dioxide, that temperature change has been 50 times faster than the very slow changes in the past 5,000 years. And it is both the amount of change and the speed that's worrisome, because the faster it changes, the harder it is to adapt to. And the more it changes, of course, the more dramatic the impacts are. We've already closed the door to one source of skepticism here about climate change because most people understand that it's impossible to predict the weather far in advance.

And from that, they conclude that it must be hard to say anything about the climate far in the future. In fact, we got one of these on Twitter. One person wrote, most forecasts can't accurately predict the weather more than five days in advance. One person wrote, most forecasts can't accurately predict the weather more than five days in advance. How can you have it right for five years or five decades ahead? So we spared one person some fatal embarrassment. I think that is a very important point worth driving home. I can't tell you in one year whether you're going to have, you know, a 100 degree Fahrenheit day or a 60 degree Fahrenheit day.

But I, you know, I do know what the average yearly temperature is. And if you look at the average yearly temperature of the globe or even the average monthly temperature, that doesn't change very much over time, unless, of course, something is forcing it to change. That's the key point. We're forcing the change. And that's why year by year, we've been seeing these hotter and hotter years. Okay, so tell me how we know that we are forcing this change. There's two parts here.

How we know that the climate is changing, i.e. heating up, and how we know that humanity is playing a role in changing it. And for this part, I'd really like you to limit yourself to what is totally uncontroversial from a scientific point of view. We can get into gray areas later, but is there a version of this story that is at the level of smoking is harmful to your health? Can we make it that uncontroversial? Sure, although that still won't make it uncontroversial in the sense that, as you know, the tobacco companies launched a major disinformation campaign to confuse the public for decades about the science of smoking and the health consequences. And so, you know, decades after the medical community, you know, was quite certain that smoking was bad for your health, that myth persisted. But it is true. And,

you know, in recent years, the scientific community has said that our certainty that, that the climate is changing, that humans are the primary cause, our certainty level is exactly comparable to our certainty level that cigarette smoking is bad for your health. So they are, they are comparable. One thing I want to say right away, and I'll probably repeat, anybody who wants to know the underlying science of these myths and the debunking of them, there's a website, a great website, which just had a 10th year anniversary called Skeptical Science. And it literally goes through each of these. And you can click on links to the actual scientific literature, depending on how informed you want to get. changes substantially it's because it was forced to by some external change often that change was the slow change in the Earth's orbit reducing the amount of sunlight that hit particularly the northern hemisphere and that led to the Ice Age cycle you know over the past million plus years. But those ice ages and the end of those ice ages,

as it turns out, were triggered by the changes in the Earth's orbit. But those changes then actually led to a feedback, which is release of greenhouse gases and other feedback. So we have known literally for two centuries that there are certain gases that trap heat in the atmosphere and that the major one the major one that we control is carbon dioxide and that it has been predicted it was predicted for over a century that if you keep burning, you know, the fossil fuels that have been tracked in the ground in the form of coal, oil and gas, if you keep burning those, you are going to be basically putting more and more blankets around the earth. You're going to be heating up the earth and that heating up is going to have a whole bunch

of consequences. As to the question of how do we know that humans are the major cause, the answer is twofold. One, you can look at all of the potential sources of heating and cooling, and you find, particularly in recent decades, that all of the ones that aren't human-caused would actually be cooling the Earth, because the sun's, you know, solar radiation has actually declined slightly in recent decades. We've had volcanoes. They're another cooler, because they put in aerosols that block the sun. because they put in aerosols that block the sun. So if you take away all of the so-called natural cycles and natural things that change the climate, you would find that the vast majority of warming since the middle last century is due to human activity, principally the release of

these heat-trapping gases. And in fact, not only did the scientific community conclude in its most recent assessment, every five years, all the world's leading scientists review all the scientific literature and the issue reports to the world government. Those are the Intergovernmental Panel on Climate Change. And those reports, by the way, are literally argued over line by line by all of the governments of the world. So they end up as the least common denominator. And those studies, the most recent one concluded two things. There is a 95 to 100 percent chance that that most of the recent warming is due to humans. And at the same time, the best estimate for how much of recent warming is due to humans is all of it, 100%. So the peak in the most likely scenario is that humans are responsible for all of the warming since 1950, but like a, you envision a

curve, like a bell curve, there are small chances that all humans are only responsible for, let's say, 75%. But, you know, there's no point in getting into a lot of detail on that because this is not a subject of much debate at all in the side of the community. I'm actually wondering

whether it's relevant in the end. So there are at least three parts to this story. There's the fact that the planet has been warming over the last century. There's the fact, or at least the claim, that human behavior has contributed to it, either in part or in entirety. And then there's the claim that warming past a certain point would be catastrophic for us, and we will definitely get into that. But this third claim, in my view, seems to undercut the significance of the second. I mean, if warming past a certain point is going to be catastrophic for us, it doesn't much matter who caused it, right, or what the cause is. We'd want to find some way of mitigating this warming,

it, right, or what the cause is. We'd want to find some way of mitigating this warming, arresting it and mitigating it anyway, right? Well, I don't entirely agree with that in the following sense. Knowing that humans are the major cause tells us we are the major solution. If this were just an underlying natural change, like the incredibly slow changes in and out of the ice ages, then, you know, there's not much we could do. I mean, we could adapt. We could plan for the changes, but we couldn't stop the changes. The fact that we know that we are, you know, essentially all of the cause of recent warming tells us that if we were to change, you know, replace fossil fuel combustion with, you know, clean energy, renewables and the like, that we would slow and ultimately stop the amount of warming. And so that's sort of point one. Point two... Joe, let me just jump in there. I totally agree with that in that it points to a way forward toward a solution. But given the predicted consequences here, a sudden warming, not a gradual warming, would be bad for us whether or not we're the cause. And if there's any way

to mitigate it, we would be interested in doing that. I guess what I'm trying to do here is differentiate the problem as we face it from a kind of common attitude you find among people, which is just a matter of disapproving of human caused change in principle, analogous to thinking that it was a bad thing that we wiped out the dodo bird. There's a kind of a sentimentality for nature that I don't want us to be confused by. I'm not saying I don't share it, but that's not really the issue. The issue is if the average temperature of the planet keeps going up and we hit the most dire projections, whatever the cause, we have a huge problem for which we should be seeking a solution. Right. But let me, if one thing I can get out of this discussion with you is to persuade you that the phrase and it is false, it's wrong, it isn't whatever the cause.

If we didn't know the cause, then we wouldn't know that warming is not only going to continue, it's going to speed up, right? We're not, this is science, you know, we put 12 men on the moon and we got them back. We don't make guesses. And the scientific community as a whole doesn't come out and say, you know, on our current path of burning fossil fuels, we are headed towards rates of warming that will have catastrophic impacts. If you took away the cause, then you would be able to make no statements about the future. At the end of the day, what science is, is an ability to make testable predictions.

And if your predictions don't come true, you know your theory is wrong. And if they do come true, then you have growing confidence in that theory. So no, I don't use the phrase whatever the cause, because we know the cause, and that's how we know what's going to happen. And that's why we know it's going to happen literally, you know, thousands of times faster than whenever the climate changed, you know, because of purely, you know, orbital or natural changes. And we are, in fact, acidifying the oceans, you know, more than 10 times faster than ever happened before under, you know, previous, you know, dating back millions and millions of years. Can I make one other point, which I'm not going to go into, but you can read my book. The type of warming that we're getting is also the exact type of warming that you would expect if it were due to greenhouse gases.

gases. And I go through that in the book, the fact that the lower troposphere, you know, the air near where we are is warming quickly. But in fact, if you go high enough in the atmosphere to the stratosphere, it's actually cooling. But it's only cooling there because the warming is caused by a heat trapping layer lower than that. So, you know, I don't, the point is I don't want to get technical, but one of the reasons that scientists have so much confidence that humans are the cause is the theory predicted that greenhouse gases would cause the warming. The type of warming is the kind of warming that you would have expected from greenhouse gases. And all of the other things that cause warming, A, aren't, you know, moving in the direction that caused warming. And again, the type of warming we're getting is not the type of warming they would cause. That's why you get these incredibly strong statements

that we know humans are the primary, indeed, almost entirely the cause of recent warming. Well, Joe, those are exactly the kinds of technical details I want you to bring forward because, as you know, in the absence of a statement of the sort you just made, skeptics take the fact that part of the atmosphere is warming and part is cooling as a sign of the ambiguity of the situation. Even a coarser-grained source of confusion, true or feigned on the part of the situation, that even a coarser-grained source of confusion, true or feigned on the part of skeptics, is the fact that what is predicted in terms of the results of global warming entails both conditions of drought, but also increased flooding. And so now you have

a climate change skeptic laughing over the imponderable fact there that, you know, what is this, some sort of scientific koan where you're telling me we're going to have a drought and lots of flooding? So it's good for you to make sense of all of that as we move forward. Before we get into the details of what's predicted, what are some of the feedback mechanisms that cause this to get out of hand in ways that may be counterintuitive so that where an initial warming can become far more substantial? Well, one of the best known feedbacks is the loss of ice on land and the ocean, particularly the Arctic Ocean. So what happens is that as the planet warms up, of course, ice melts. Now, ice is highly reflective. So if the ice is on the land, then as the ice retreats,

you're exposing the land, which is dark, and therefore, whereas ice might reflect 90, 95% of the light that hits it, the ground absorbs most of the light. So you're actually, as the ice retreats, the Earth is actually absorbing more of the sun's heat, and therefore it heats up faster, and therefore the ice retreats more. And so that is one of the best known uh feedback effects and that is occurring both on land and you know as as we get the reports year by year the arctic ocean the arctic ice cover particularly during the summer uh is retreating rapidly and again when you replace ice covered ocean with the blue wavy ocean, you know, you get

the ocean absorbing considerably more of the sun's energy than it was when it had a nice insulation blanket, if you will, from, um, from the ice. Uh, so that's a classic that that's, that's called a fast feedback. And that is, that is one of the best known. And we're clearly witnessing it now. It's one reason, by the way, that the warming is occurring twice as fast in the Arctic as it is in the rest of the globe. And now there's also a feedback mechanism with respect to water vapor, right? Yes, that's another fast feedback. So water vapor is a heat-trapping gas. So when you start the initial process of warming through injecting a large amount of greenhouse gases or changing the earth's orbit, a large amount of greenhouse gases or changing the Earth's orbit, then you start to evaporate more water as you warm up the planet. And that water goes into the atmosphere and it also traps heat.

So that is a feedback, too. Yes. And that is another major fast feedback. I think I've seen that fact in isolation seized upon by skeptics as a sign of just how preposterous the situation is as described by science. Yes. And again, this is the kind of thing if you, you know, skeptical science will go into details if anyone is interested, that most of the warming is due to the water vapor. The excess water vapor is there because of the excess carbon pollution. By the way, it should be said, people should understand that the greenhouse effect is not controversial in the least.

If you took, we have an atmosphere. That's why we have a habitable planet. That's why we're not Mars, right? If you took away the entire atmosphere, the carbon dioxide, the water vapor, everything that traps heat, the planet would be 60 degrees Fahrenheit colder. So there would not be a lot of places that would be very hospitable for life. for life. One problem here strikes me is that the changes in temperature that people are worried about don't seem so great. When you look at your thermometer or you judge the weather for yourself on any given day, when you hear about a two degree rise Celsius, you know, like 3.6 degrees Fahrenheit or a four degree rise, or even in the worst case, an eight degree rise.

If you told me 30 years from now, my children will be living in a world that is on average four degrees Celsius warmer, it's not immediately obvious why that would be a big deal. If you don't like the heat, you just move further north, right? You just, you know, Canada is going to be great. What are the likely effects of these changes in temperature as we go up in increments of two, four and six degrees Celsius? Well, I think this is a very good point. First of all, obviously, the rest of the world talks Celsius. And whereas Americans have, you know, in their mind, their temperature gradations are based on Fahrenheit. So, you know, I think it is better to talk about Fahrenheit.

It's still a small number. widely viewed in the scientific community and and by essentially all the major governments in the world except our current one as a threshold beyond which climate impacts be moved from being dangerous to being catastrophic at a very rapid rate um now you can look at it a couple of different ways one of which is that the average temperature going up pushes the extremes up much faster. And I have a chart in the book that shows that. If you can visualize a bell curve in your head, where at the very right side is that tail where you get the monster heat waves that really are devastating to people in agriculture or the monster droughts or the monster super storms. They are a teeny fraction of the area under the bell curve. But if you now visualize that bell curve shifting a couple of degrees to

the right, all of a sudden what had been very infrequent events, all of a sudden start to become quite frequent. And that's why you hear that like a super storm Sandy, which might be a once in a thousand year storm, is now actually under a once in a century storm. And in fact, Sandy was followed Hurricane Irene, which was also at the time, a once in a century storm. And so you see, you know, you can't, you know, storms that used to be once in a century, once in 500 years, if they're now coming every few years, you know, it's because we've changed at the high end of the far end of the bell curve, Because we've changed at the high end, the far end of the bell curve, the frequency of the really rare events. And historically, it has been the really rare events that have done most of the devastation.

In the history of hurricanes, it has literally been seven or eight or nine hurricanes that have done half of the damage. You know, Katrina and Sandy, these are the two most destructive storms. And so they're outliers. So part one, the reason we worry about this is we're very concerned about the outlier events because they're the true catastrophes. Secondly, you know, when you look at, let's say, Superstorm Sandy, one of the things that warming changes is sea levels. And as you raise sea levels, every storm that you see is going to have a storm surge, which is higher and higher because it's the underlying average sea level keeps going up. So, you know, you get that impact of whatever the weather was going to be. Now you have global warming on top of it. That's why, for instance, El Nino years, which which are, you know, years that have freaky weather and are slightly warmer than usual. They tend to be the hottest years on record because the the the small amount of the extra regional warming from the El Nino

is put on top of the global warming trend. Now, you know, we've had 2014 was the hottest year on record, and then 2015 beat that easily to become the hottest year on record, and then 2016 beat that. So we, you know, we've been seeing unprecedented, you know unprecedented records in warming, and 2017 is on track to probably be the second warmest year on record, but the hottest year on record without an El Nino. So we're starting to see, the point is we're starting to see levels of warming that you normally only see during extreme years be the normal weather. And so that's where, and that's, in other words, the climate is changing. And that's what I try to tell people, for instance, when I talk about drought. You know, you can look at the California drought, which lasted five, six years, and that was the worst drought in a thousand years. But the point is

that as you make the average rainfall a little less and the average temperature higher, then suddenly that type of drought becomes a 10-year drought or a 20-year drought. And instead of it happening every 100 years, it happens every 10 years. So that is one, you know, obvious thing that is why even small temperature changes can have a big impact. Just by the way, I mean, another analogy people use is, you know, if you imagine a planet to be like a human being, it's designed, you know, we spent 10,000 years at a relatively constant set of weather patterns over time. The climate didn't change very much. Billions of people have chosen where to live based on their knowledge of is it too warm here? No.

Is there enough rainfall to sustain life? Yes. Is the sea level endangering us? No. So the point is, we've literally 8 billion people are living in places that they chose to live on based on a relatively stable climate. You now add a few degrees to that, and it's literally like adding a few degrees Celsius or, you know, or twice that Fahrenheit, five degrees, let's say, Fahrenheit to your body temperature. So our entire body temperature is constructed around 98.6, and we have mechanisms in our body, as I'm sure you know, to regulate that temperature. as I'm sure you know, to regulate that temperature. And if you start going outside of that bounds, it means something is wrong. And if it stays outside that bound for a long period of time, it has dire consequences. Well, the same is true for the climate. You know, if we could, if the planet warmed two degrees and stopped, then we would adjust to that. But that still

doesn't mean that the 8 billion people who live where they do now wouldn't have to move. You know, a billion or 2 billion people moving, you know, this is a catastrophe, right? I mean, we saw what, 2 or 3 million refugees from Syria turned global politics upside down. Well, let's talk about that for a second. Why people would need to move, I guess two obvious reasons come to mind. You're talking about sea level change, so the inundation of certain coastal areas, and you're talking about the dust bolification of certain areas where we depend upon agriculture to be viable. Perhaps there are other reasons that I haven't thought of. Tell me about certainly those two variables and anything else relevant to

deranging global politics. Sure. Well, people talk a lot about different impacts. So certainly, I would, if your listeners come away from anything, I would want them to think in terms of the two most worrisome impacts is, yes, dust volification. Turning an area that was, let's say, semi-arid, but could grow crops and sustain life into something that's purely arid, ultimately a desert. But in the transition from it being semi-arid or near semi-arid to becoming a desert, it's just going to get drier and hotter and droughts are going to last longer and longer. And we know that, again, we have designed an agricultural system of the world in which we feed large amounts of the world from relatively small tracts of land. I mean, we have two breadbaskets in this country, you know, the Midwest extending to the Great Plains and California, even though, of course, Southern California is essentially a semi-arid, near-desert

climate. So again, if you just shift the climate zones a little bit, all of a sudden, you find that your breadbaskets are getting these mega droughts on a regular basis. And many of our crops are quite temperature sensitive. People want to Google, you know, corn and temperature sensitivity. They will learn, you know, a great deal about it. So the point is that, yes, you know, much of our population is fed by an agricultural system that truly wants a stable climate. You know, talk to a farmer. The thing that causes the most problems, obviously, is extreme weather variability. Too much rain, too little rain. It's too hot or it's too cold.

So that's an enormous problem. You know, literally, there are lots of people living in places where they're not going to have sources of food. And by the way, this is also related to sea level rise because many of our richest agricultural areas are deltas, right? The Nile Delta and the low-lying areas of Bangladesh and Southeast Asia. So you raise sea levels a couple of feet and suddenly the many rich deltas that were feeding hundreds of millions of people, they are flooded. And of course, they're flooded with saltwater. And that saltwater intrusion, by the way, is already happening. As sea levels rise, saltwater goes further and further up those deltas. And if you Google saltwater intrusion, you will find that is a mammoth problem already for places like Egypt and Bangladesh and the water systems of Miami. So part one is, are you going to be able to feed?

I mean, we're going to have 10 billion people in mid-century. going to have 10 billion people in mid-century. And I wrote an article for Nature on dust bolification, it's titled The Next Dust Bowl, saying the biggest threat facing humanity is how are we going to feed 10 billion people when we're moving in a rapidly changing climate to a world that has less potable water, less arable land, and much more intensive droughts and super storms. So, you know, that is problem number one for billions of people and the choices that they've made where they live now. The second is sea level rise. People, you know, most of the population in the world, or half the population in the world lives within, you know, 50 miles of the population of the world or half the population of the world lives within 50 miles of the ocean. People like to be near water.

Water has made trade possible. Most of your major cities are near waterways, near the ocean, historically and even today. So we have billions of people. So we have, you know, billions of people, you know, and so we have hundreds of millions of people who live right on the ocean, you know, and in places like Bangladesh and even places like, you know, Miami and Louisiana and Norfolk, Virginia, or even Los Angeles. We have staggering amounts of people who live where they live because sea levels have been, you know, until recent decades, pretty damn stable. And we are now moving to a situation where we are, where the worst case scenarios of sea level rise appear to be the ones that we are facing. And if you were to have a leading expert, a glaciologist expert on Greenland or Antarctica, they would tell you that the great ice sheets are melting much faster than anyone

thought, and that we may be much closer to tipping points beyond which we can't stop them. And therefore, we look to be headed to what used to be the worst case levels of sea level rise are now pretty much the business as usual projections. I'm talking about three, four, five feet. And, you know, if you can go online and find, you know, programs that allow you to look at the coast coast of the world, coast of different cities under three, four or five feet. But I can tell you that all of South Florida, if you've been there, you know how flat and low lying it is. It's simply not possible that South Florida is habitable, you know, by the end of the century under those scenarios.

But the same is true of Bangladesh and the same is true of, you know, lots of places in this country and lots of places around the world. So, again, we are talking about places where hundreds of millions of people live are simply going to be either underwater or they're just going to be routinely drenched in storm surges. I mean, after all, you don't, you know, you, you, you know, we don't live in places that are, you know, routinely dunked by storm surges, but all the storm surges are on top of the sea level rise. So we don't, you know, no one lives, I didn't say no one, but we don't live right at sea level rise, right?

Because you have the tides and you have storm surges. So, yes, the kind of withdrawal is starting to happen, you know, is going to be sped up. And so we are going to end up with 100 serious worth of failed states, inundated areas, and refugees. That's where we're headed towards. And that's, of course, why the Pentagon is incredibly concerned about climate change. And the Pentagon has been issuing report after report saying, you guys, climate change is going to become a major driver of civil conflict as people fight for scarce fresh water, as people are forced out of their homes.

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