Making Sense - Sam Harris - September 05, 2017


#95 — What You Need to Know About Climate Change


Episode Stats

Length

46 minutes

Words per Minute

150.00217

Word Count

6,942

Sentence Count

351

Misogynist Sentences

1

Hate Speech Sentences

5


Summary

Joe Rome 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. And he is the author of Climate Change: What Everyone Needs to Know, which is organized in Q&A format so that every question you have ever had or heard posed, skeptical or otherwise, about climate change seems to be answered in this book. In this episode, we talk about how we know the climate is changing, and why 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 discuss the threats of sea level rise and desertification, and the best and worst case scenarios given where we currently are. And we discuss what many people don t know about it, and I suppose what many refuse to know about it. Thanks for coming on the podcast. I am here with Joe Rome, and I m here to talk to him about what we know, and what we don't know, about it. And I hope you enjoy what we're doing here, and that you do, too, to make sense of it. Thanks for listening to the Making Sense Podcast! Sam Harris - The Making Sense Podcatcher by The Climate Project, by . by Think Progress, , by Harvard Lampoon, and by the National Association of Clean Energy and Climate Change by Tom Friedman , and is a podcast produced by the Climate Progress Podcast in partnership with The Climate Progress Project, by , by & ( ) -- on this podcast is ? "The Indispensible Blog? And has a blog post about this is , . ... This is an excellent piece by the or can be found here? , in this is a tweet about this ) , this is an a tweet out of this , which : so let me know what you think about it? and so on I think it's a good one? ... and , I think so?


Transcript

00:00:00.000 Welcome to the Making Sense Podcast.
00:00:08.820 This is Sam Harris.
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00:00:46.420 My guest today is Joseph Rome.
00:00:49.300 Joe is one of the country's most influential communicators on climate science and solutions.
00:00:53.500 He was chief science advisor for the show Years of Living Dangerously, which won the 2014
00:01:00.480 Emmy Award for Outstanding Nonfiction Series.
00:01:04.060 He is the founding editor of Climate Progress, which Tom Friedman of the New York Times called
00:01:09.500 the Indispensable Blog.
00:01:11.920 In 2009, Time named him one of the heroes of the environment, and Rolling Stone put him
00:01:17.920 on his list of 100 people who are, quote, reinventing America.
00:01:22.460 Rome was acting assistant secretary of energy in 1997, and he's a fellow at American Progress
00:01:29.120 and holds a PhD in physics from MIT.
00:01:33.420 And perhaps most relevant, he is the author of Climate Change, What Everyone Needs to Know,
00:01:39.380 put out by Oxford University Press.
00:01:41.100 And it is a very handy, accessible, comprehensive book that is organized in Q&A format.
00:01:48.900 So every question you have ever had or heard posed, skeptical or otherwise, about climate
00:01:54.620 change seems to be answered in this book.
00:01:57.780 And Joe and I get into many of the details.
00:01:59.840 We talk about how we know the climate is changing and how we know that human behavior is the primary
00:02:04.480 cause.
00:02:04.940 We talk about feedback mechanisms that increase the problem of global warming and why small
00:02:11.520 changes in temperature matter so much.
00:02:14.400 We talk about the threats of sea level rise and desertification and the best and worst case
00:02:21.280 scenarios given where we currently are.
00:02:24.060 We talk about the much maligned Paris Climate Agreement and the politics surrounding climate
00:02:30.940 science.
00:02:31.380 And now, without further delay, I bring you Joe Rome.
00:02:42.040 I am here with Joe Rome.
00:02:43.860 Joe, thanks for coming on the podcast.
00:02:45.640 Thanks for having me, Stan.
00:02:47.200 We're going to talk about climate change, which, as you know, is a big and important topic.
00:02:52.320 And we will talk about what we know about it, what we don't know about it.
00:02:57.460 And I suppose what many people refuse to know about it.
00:03:02.200 But first, before we jump in, can you describe your background scientifically and in policy
00:03:09.180 circles and just the work you've done on this issue?
00:03:12.080 Sure.
00:03:12.800 Well, I have a PhD in physics for my T.
00:03:16.500 And I spent a year on Capitol Hill as a Congressional Science Fellow.
00:03:25.560 And then I went to work at the Rockefeller Foundation for a couple of years looking at
00:03:33.100 issues like the environment and national security and energy.
00:03:37.560 And I worked with Amory Lovins for a couple of years, the father of energy efficiency, really
00:03:44.780 a great guy.
00:03:46.140 And then five years at the U.S. Department of Energy during the Clinton administration, where
00:03:51.600 I ended up acting Assistant Secretary for Energy Efficiency and Renewable Energy, which is the
00:03:57.760 billion dollar office that does all the clean energy research, development, demonstration
00:04:03.000 programs for the federal government.
00:04:07.680 And then I left to do a lot of consulting with companies on how to reduce greenhouse gas
00:04:13.120 emissions and how to use efficiency and renewables.
00:04:16.500 And then August 29, 2005, Hurricane Katrina destroyed my brother's home.
00:04:24.840 He lives in Paschristian, Mississippi, and a mile inland, there was, you know, a 20-foot
00:04:33.140 storm surge, and the inside of the house looked like a washing machine.
00:04:36.340 He asked me if he should rebuild his home.
00:04:39.200 And I started talking to climate scientists and hurricane experts and reading the literature
00:04:46.880 and going to conferences.
00:04:48.360 And that's when I realized that two things, climate change was a lot more dire than I
00:04:55.980 realized, and that scientists weren't doing a very good job of communicating it.
00:05:02.680 And since I had been raised by newspaper people, my father's a newspaper editor, I decided to
00:05:11.960 stop doing clean energy consulting and just do writing and communications on climate change.
00:05:16.760 And I was able to get a position at the Center for American Progress, which had recently started
00:05:22.940 and launched its ThinkProgress website, which is one of the most widely read news, progressive
00:05:32.260 news websites in the world.
00:05:35.800 And that was about 11 years ago, 11 years ago next week.
00:05:40.060 I launched climateprogress.org, which grew over time into a, you know, we now have a staff
00:05:55.040 of five or six reporters.
00:05:57.780 It's part of the larger ThinkProgress enterprise.
00:06:02.700 If you go to ThinkProgress, you'll see articles by me and other people on clean energy and climate
00:06:09.160 change.
00:06:10.160 And it's probably the most widely read climate website in the world.
00:06:16.380 And that's what I've been doing for 11 years.
00:06:20.960 I also worked with the Years of Living Dangerously TV series.
00:06:24.700 Some of you may have seen on Showtime a few years ago or last year on National Geographic
00:06:31.920 Channel, that's the James Cameron, Arnold Schwarzenegger series, Emmy-winning series that documents
00:06:41.980 what's going on on climate change, what the solutions are.
00:06:47.060 And so that's what I've been doing.
00:06:49.100 You know, I'm very fortunate to, you know, be able to keep track of climate change and clean
00:06:55.880 energy and write about it and speak about it.
00:06:57.980 Yeah, and you've written this very lucid book that's right on point, titled Climate
00:07:04.160 Change, What Everyone Needs to Know, published by Oxford University Press, which is not actually
00:07:09.440 known for publishing propaganda.
00:07:12.220 And if I'm not mistaken, your PhD in physics from MIT was not focused in some totally unrelated
00:07:20.420 area.
00:07:21.400 Didn't you have some focus on oceanography?
00:07:23.780 It did focus on oceanography.
00:07:26.020 Yeah, I was fortunate.
00:07:28.040 I was able to do my PhD thesis with a man named Kostad Zepes, who back in the day, you know,
00:07:37.660 wrote a great number of scientific American pieces, particularly on arms control issues.
00:07:44.580 And he allowed me to do my thesis research at the Scripps Institution of Oceanography with
00:07:53.980 Walter Monk, one of the world's greatest oceanographers, and actually did my thesis.
00:08:00.320 It wasn't on climate change at all, but the thesis itself was an analysis of data from the
00:08:06.620 Greenland Sea, and, you know, just being at Scripps and attending seminars by some of the
00:08:15.220 world's greatest oceanographers, you know, I couldn't help.
00:08:19.440 But also learned at the time, this was the mid-1980s, before a lot of people were talking
00:08:26.300 about climate change, they were talking about climate change.
00:08:28.960 So that was a true education.
00:08:32.340 Right, right.
00:08:34.100 So before we jump into the details here, I should say that my goal in this conversation
00:08:39.540 is to dispel the most consequential forms of confusion on this topic.
00:08:45.460 And so I went out on Twitter when I knew we were going to do this interview, and I announced
00:08:50.720 that I'd be doing a podcast on climate change, and I asked people to post questions.
00:08:53.860 And I got over 1,000 responses, so there's no shortage of questions here.
00:08:58.960 But let's start with the basic picture of what's going on.
00:09:03.000 And I want to get into the weeds, but I don't want us to assume that people know much of anything
00:09:09.100 about this issue, because despite its enormous importance, most people, certainly many people,
00:09:15.680 don't.
00:09:16.280 So first, what is the difference between climate and weather?
00:09:19.280 Well, weather, climate, they say, is what you expect, and weather is what you get.
00:09:26.500 So weather is highly variable day to day.
00:09:30.080 Is it going to be cloudy?
00:09:31.520 Is it going to rain?
00:09:32.700 Is it going to be a very hot day?
00:09:34.640 Is it going to be a coolish day?
00:09:37.580 That's the weather.
00:09:39.640 But of course, on a given day, whether it's warm or cold is relative to what the underlying
00:09:45.740 climate is.
00:09:46.520 A hot day in the summer is obviously quite different than a hot day in the winter.
00:09:51.480 So weather forecasting is obviously tricky, hard to do more than a week, 10 days in advance.
00:09:58.340 But climate is the statistical aggregation of all the weather.
00:10:02.900 So climate tells you it's going to be warmer in the summer.
00:10:06.640 Climate tells you the Greenland is going to be colder than the Sahara Desert, and the Sahara
00:10:11.940 Desert is going to be drier.
00:10:13.420 So the long-term trends in your local climate are very slow moving.
00:10:23.820 And one of the points that I make in the book and on the website is that since we came out
00:10:30.960 of the last ice age 11,000 years ago, the Earth's climate has been very stable.
00:10:36.360 And the temperature has really varied over maybe half a degree Fahrenheit, plus or minus.
00:10:44.240 And that stable climate is what allowed people to settle in cities.
00:10:50.580 They had reliable...
00:10:52.680 The weather wasn't constantly changing.
00:10:55.180 They knew what the rainfall would be.
00:10:56.760 They knew what sea levels would be.
00:10:59.320 People, therefore, could have large-scale agriculture.
00:11:03.280 And that led to cities.
00:11:04.420 And that has sustained now a population of over 8 billion people.
00:11:09.020 But, you know, because we have been pouring vast amounts of heat-trapping greenhouse gases into
00:11:17.900 the atmosphere, we have seen a rapid rise in temperature, particularly over the last century
00:11:25.820 or so.
00:11:27.000 So when, in fact, the temperature of the Earth driven by greenhouse gases, driven by burning
00:11:35.060 fossil fuels, coal oil and gas, and releasing carbon dioxide, that temperature change has
00:11:40.940 been 50 times faster than the very slow changes in the past 5,000 years.
00:11:47.660 And it is both the amount of change and the speed that's worrisome, because the faster
00:11:54.160 it changes, the, you know, the harder it is to adapt to.
00:11:57.420 And the more it changes, of course, the more dramatic the impacts are.
00:12:02.060 We've already closed the door to one source of skepticism here about climate change, because
00:12:06.660 most people understand that it's impossible to predict the weather far in advance.
00:12:11.960 And from that, they conclude that it must be hard to say anything about the climate far in
00:12:17.280 the future.
00:12:18.140 In fact, we got one of these on Twitter.
00:12:20.440 One person wrote, most forecasts can't accurately predict the weather more than five days in
00:12:24.480 advance.
00:12:25.400 How can you have it right for five years or five decades ahead?
00:12:29.020 So we spared one person some fatal embarrassment.
00:12:31.820 I think that is a very important point worth driving home.
00:12:36.260 I can't tell you in one year whether you're going to have, you know, a 100-degree Fahrenheit
00:12:45.020 day or a 60-degree Fahrenheit day.
00:12:48.820 But I, you know, I do know what the average yearly temperature is.
00:12:53.460 And if you look at the average yearly temperature of the globe or even the average monthly temperature,
00:12:59.120 that doesn't change very much over time.
00:13:03.320 Unless, of course, something is forcing it to change.
00:13:06.140 That's the key point.
00:13:07.140 We're forcing the change.
00:13:09.240 And that's why, year by year, we've been seeing these hotter and hotter years.
00:13:15.280 Okay.
00:13:15.440 So tell me how we know that we are forcing this change.
00:13:20.320 There's two parts here.
00:13:21.340 How we know that the climate is changing, i.e. heating up, and how we know that humanity
00:13:29.500 is playing a role in changing it.
00:13:31.840 And for this part, I'd really like you to limit yourself to what is totally uncontroversial
00:13:37.940 from a scientific point of view.
00:13:39.320 And we can get into gray areas later.
00:13:41.480 But is there a version of this story that is at the level of smoking is harmful to your
00:13:48.820 health?
00:13:49.380 Can we make it that uncontroversial?
00:13:52.560 Sure.
00:13:53.180 Although that still won't make it uncontroversial in the sense that, as you know, the tobacco
00:13:58.220 companies launched a major disinformation campaign to confuse the public for decades about the
00:14:05.600 science of smoking and the health consequences.
00:14:10.280 And so, you know, decades after the medical community, you know, was quite certain that
00:14:16.700 smoking was bad for your health, that myth persisted.
00:14:21.020 But it is true, and, you know, in recent years, the scientific community has said that our
00:14:27.200 certainty that the climate is changing, that humans are the primary cause, our certainty
00:14:33.800 level is exactly comparable to our certainty level that cigarette smoking is bad for your
00:14:38.560 health.
00:14:38.940 So they are comparable.
00:14:41.760 One thing I want to say right away, and I'll probably repeat.
00:14:45.060 Anybody who wants to know the underlying science of these myths and the debunking of them, there's
00:14:53.900 a website, a great website, which just had its 10th year anniversary called Skeptical Science.
00:15:00.500 And it literally goes through each of these.
00:15:05.820 And you can click on links to the actual scientific literature, depending on how informed you want
00:15:11.360 to get.
00:15:11.660 So fundamentally, if you look over the history of the Earth, whenever the climate changes
00:15:20.940 substantially, it's because it was forced to by some external change.
00:15:26.780 Often that change was a slow change in the Earth's orbit, reducing the amount of sunlight
00:15:34.120 that hit particularly the northern hemisphere.
00:15:36.940 And that led to the ice age cycle, you know, over the past million plus years.
00:15:44.800 But those ice ages and the end of those ice ages, as it turns out, were triggered by the
00:15:51.520 changes in the Earth's orbit.
00:15:52.680 But those changes then actually led to a feedback, which is release of greenhouse gases and other
00:15:58.020 feedback.
00:15:58.420 So we have known literally for two centuries that there are certain gases that trap heat
00:16:07.380 in the atmosphere.
00:16:08.580 And that the major one, the major one that we control is carbon dioxide and that it has
00:16:17.760 been predicted.
00:16:18.540 It was predicted for over a century that if you keep burning, you know, the fossil fuels
00:16:26.280 that have been tracked in the ground in the form of coal, oil and gas, if you keep burning
00:16:32.120 those, you are going to be basically putting more and more blankets around the Earth.
00:16:38.140 You're going to be heating up the Earth.
00:16:39.980 And that heating up is going to have a whole bunch of consequences.
00:16:45.680 As to the question of how do we know that humans are the major cause, the answer is twofold.
00:16:52.200 One, you can look at all of the potential sources of heating and cooling.
00:16:56.920 And you find, particularly in recent decades, that all of the ones that aren't human-caused
00:17:06.820 would actually be cooling the Earth because the sun's, you know, solar radiation has actually
00:17:13.560 declined slightly in recent decades.
00:17:16.820 We've had volcanoes.
00:17:18.460 They're another cooler because they put in aerosols that block the sun.
00:17:22.800 And so if you take away all of the so-called natural cycles and natural things that change
00:17:33.800 the climate, you would find that the vast majority of warming since the middle last century is
00:17:44.900 due to human activity, principally the release of these heat-trapping gases.
00:17:50.500 And in fact, not only did the scientific community conclude in its most recent assessment, every
00:17:58.520 five years, all the world's leading scientists review all the scientific literature and they
00:18:04.240 issue reports to the world government.
00:18:06.380 Those are the Intergovernmental Panel on Climate Change.
00:18:08.800 And those reports, by the way, are literally argued over line by line by all of the governments
00:18:15.340 of the world.
00:18:16.080 So they end up as the least common denominator.
00:18:20.740 And that, those studies, the most recent one concluded two things.
00:18:25.420 There is a 95 to 100% chance that most of the recent warming is due to humans.
00:18:34.340 And at the same time, the best estimate for how much of recent warming is due to humans is
00:18:43.640 all of it, 100%.
00:18:45.420 So the peak in the most likely scenario is that humans are responsible for all of the
00:18:52.300 warming since 1950.
00:18:54.180 But, you know, like a, you know, you envision a, you know, a curve, like a bell curve, you
00:19:02.880 know, there are small chances that all humans are only responsible for, let's say, 75%.
00:19:09.980 But, you know, there's no point in getting into a lot of detail on that because this is not
00:19:14.980 a subject of much debate at all in the side of the community.
00:19:19.640 I'm actually wondering whether it's relevant in the end.
00:19:23.060 So there are at least three parts to this story.
00:19:26.420 There's the fact that the planet has been warming over the last century.
00:19:29.580 There's the fact, or at least the claim, that human behavior has contributed to it, either
00:19:36.660 in part or in entirety.
00:19:39.160 And then there's the claim that warming past a certain point would be catastrophic for us.
00:19:44.840 And we will definitely get into that.
00:19:47.300 But this third claim, in my view, seems to undercut the significance of the second.
00:19:52.660 I mean, if warming past a certain point is going to be catastrophic for us, it doesn't
00:19:58.080 much matter who caused it, right, or what the cause is.
00:20:01.820 We'd want to find some way of mitigating this warming, arresting it and mitigating it anyway,
00:20:07.180 right?
00:20:08.020 Well, I don't entirely agree with that in the following sense.
00:20:13.440 Knowing that humans are the major cause tells us we are the major solution.
00:20:20.200 If this were just an underlying natural change, like the incredibly slow changes in and out
00:20:28.200 of the ice ages, then, you know, there's not much we could do.
00:20:33.260 I mean, we could adapt.
00:20:34.440 We could plan for the changes, but we couldn't stop the changes.
00:20:40.100 The fact that we know that we are, you know, essentially all of the cause of recent warming
00:20:45.420 tells us that if we were to change, you know, replace fossil fuel combustion with, you know,
00:20:53.300 clean energy, renewables and the like, that we would slow and ultimately stop the amount
00:21:00.780 of warming.
00:21:01.820 And so that's sort of point one.
00:21:04.840 Point two...
00:21:06.060 Joe, let me just jump in there.
00:21:06.860 I totally agree with that in that it points to a way forward toward a solution.
00:21:11.000 But given the predicted consequences here, a sudden warming, not a gradual warming, would
00:21:18.080 be bad for us, whether or not we're the cause.
00:21:21.500 And if there's any way to mitigate it, we would be interested in doing that.
00:21:25.900 I guess what I'm trying to do here is differentiate the problem as we face it from a kind of common
00:21:33.080 attitude you find among people, which is just a matter of disapproving of human-caused change
00:21:39.640 in principle, analogous to thinking that it was a bad thing that we wiped out the dodo
00:21:44.600 bird.
00:21:45.180 There's a kind of a sentimentality for nature that I don't want us to be confused by.
00:21:52.140 I'm not saying I don't share it, but that's not really the issue.
00:21:55.960 The issue is if the average temperature of the planet keeps going up and we hit the most
00:22:01.640 dire projections, whatever the cause, we have a huge problem for which we should be seeking
00:22:09.020 a solution.
00:22:09.860 Right.
00:22:10.440 But let me, if one thing I can get out of this discussion with you is to persuade you
00:22:16.660 that the phrase whatever the cause is really a phrase that concedes the battle and it is
00:22:27.800 false.
00:22:28.360 It's wrong.
00:22:28.900 It isn't whatever the cause.
00:22:30.240 If we didn't know the cause, then we wouldn't know that warming is not only going to continue,
00:22:36.520 it's going to speed up.
00:22:38.900 Right.
00:22:39.460 We're not, this is science.
00:22:41.340 You know, we put 12 men on the moon and we got them back.
00:22:43.840 We don't make guesses.
00:22:45.780 And the scientific community as a whole doesn't come out and say, you know, on our current
00:22:51.120 path of burning fossil fuels, we are headed towards rates of warming that will have catastrophic
00:22:57.000 impacts.
00:22:58.160 If you took away the cause, then you'd be able to make no statements about the future.
00:23:04.120 At the end of the day, what science is, is an ability to make testable predictions.
00:23:13.620 And if your predictions don't come true, you know your theory is wrong.
00:23:17.040 And if they do come true, then you have growing confidence in that theory.
00:23:21.220 So, no, I don't use the phrase whatever the cause, because we know the cause.
00:23:26.120 And that's how we know what's going to happen.
00:23:30.280 And that's why we know it's going to happen literally, you know, thousands of times faster
00:23:37.740 than whenever the climate change, you know, because of purely, you know, orbital or natural
00:23:44.660 changes.
00:23:46.120 And we are, in fact, acidifying the oceans, you know, more than 10 times faster than ever
00:23:54.120 happened before under, you know, previous, you know, dating back millions and millions
00:23:59.440 of years.
00:24:00.840 Can I make one other point, which I'm not going to go into, but you can read my book.
00:24:04.840 The, the, there are also, the type of warming that we're getting is also, um, uh, the exact
00:24:15.840 type of warming that you would expect if it were due to greenhouse gases.
00:24:21.380 Uh, and I go through that in the book.
00:24:23.460 The fact that the, the lower troposphere, you know, the air near where we are is warming
00:24:28.660 quickly.
00:24:29.260 But in fact, if you go high enough in the atmosphere to the stratosphere, it's actually
00:24:33.480 cooling.
00:24:33.920 But it's only cooling there because the warming is caused by a heat trapping layer lower than
00:24:41.640 that.
00:24:42.440 So, you know, I don't, the point is I don't want to get technical, but one of the reasons
00:24:46.480 that scientists have so much confidence that humans are the cause is the theory predicted
00:24:52.180 that greenhouse gases would cause the warming.
00:24:55.360 The type of warming is the kind of warming that you would have expected from greenhouse gases.
00:25:02.280 And all of the other things that cause warming, A, aren't, you know, moving in the direction
00:25:08.440 of cause warming.
00:25:09.700 And again, the type of warming we're getting is not the type of warming they would cause.
00:25:13.840 That's why you get these incredibly strong statements that we know humans are the primary,
00:25:20.680 indeed, almost entirely the cause of recent warming.
00:25:23.240 Well, Joe, those are exactly the kinds of technical details I want you to bring forward,
00:25:27.720 because as you know, in the absence of a statement of the sort you just made, skeptics take the
00:25:35.480 fact that part of the atmosphere is warming and part is cooling as a sign of the ambiguity
00:25:41.920 of the situation, that even a coarser-grained source of confusion, true or feigned on the part of skeptics,
00:25:49.560 is the fact that what is predicted in terms of the results of global warming entails both conditions
00:25:56.920 of drought but also increased flooding.
00:26:00.160 And so now you have a, you know, a climate change skeptic laughing over the imponderable fact there that,
00:26:06.020 you know, what is this, some sort of scientific koan where you're telling me we're going to have a drought
00:26:10.100 and lots of flooding. So it's good for you to make sense of all of that as we move forward.
00:26:17.320 Before we get into the details of what's predicted, what are some of the feedback mechanisms
00:26:21.660 that cause this to get out of hand in ways that may be counterintuitive,
00:26:28.040 so that where an initial warming can become far more substantial?
00:26:32.840 Well, one of the best known feedbacks is the loss of ice on land and the ocean, particularly the Arctic
00:26:43.300 Ocean. So what happens is that as the planet warms up, of course, ice melts. Now, ice is highly
00:26:52.660 reflective. So if the ice is on the land, then as the ice retreats, you're exposing
00:26:58.620 the land, which is dark. And therefore, whereas, you know, ice might reflect 90, 95 percent
00:27:05.760 of the light that hits it, the ground absorbs most of the light. So you're actually, as the ice
00:27:12.660 retreats, you're, the earth is actually absorbing more of the sun's heat. And therefore, it heats up
00:27:20.260 faster. And therefore, the ice retreats more. And so that is, is, is one of the best known
00:27:26.580 feedback effects. And that is occurring both on land and, you know, as, as we get the reports year
00:27:33.860 by year, the Arctic Ocean, the Arctic ice cover, particularly during the summer, is retreating
00:27:40.120 rapidly. And again, when you replace ice covered ocean with the blue wavy ocean, you know, you get
00:27:47.740 the ocean absorbing considerably more of the sun's energy than it was when it had a nice insulation
00:27:54.640 blanket, if you will, from, from the ice. So that's a classic, that that's, that's called
00:28:03.300 a fast feedback. And that is, that is one of the best known. And we were clearly witnessing
00:28:08.620 it now. It's one reason, by the way, that the warming is occurring twice as fast in the
00:28:15.640 Arctic as it is in the rest of the globe.
00:28:19.500 And now there's also a feedback mechanism with respect to water vapor, right?
00:28:24.220 Yes, that's another fast feedback. So water vapor is a green, it's a heat trap in gas.
00:28:31.340 It is, it is. So when you start the initial process of warming through injecting a large
00:28:40.520 amount of greenhouse gases or changing the earth's orbit, then you start to evaporate more water.
00:28:49.500 As you warm up the planet and that water goes into the atmosphere and it also traps heat.
00:28:54.720 So that is a feedback too. Yes. And that's, that is a, another major fast feedback.
00:29:02.420 I think I've seen that fact in isolation seized upon by skeptics as a sign of just how preposterous
00:29:09.740 the situation is as described by science.
00:29:12.200 Yes. And, and, and, and again, this is the kind of thing if you, you know, skeptical science
00:29:16.080 will go into details. Oh, um, if, if anyone is interested that most of the warming is due
00:29:23.820 to the water vapor, but the excess water vapor is there because of the excess, uh, carbon
00:29:31.880 pollution. By the way, it should be said, people should understand that the greenhouse effect
00:29:36.800 is, is not controversial in the least. If you took that, we have an atmosphere. That's
00:29:41.920 why we have a habitable planet. That's why we're not Mars, right? If you took away the
00:29:46.840 entire atmosphere, the carbon dioxide, the water vapor, everything that traps heat, the
00:29:51.660 planet would be 60 degrees Fahrenheit colder. So there would not be a lot of places that would
00:29:57.280 be very hospitable, uh, uh, for life.
00:30:01.780 One problem here strikes me is that the changes in temperature that people are worried about
00:30:08.200 don't seem so great. When you look at your thermometer or you judge the weather for yourself
00:30:14.540 on any given day, when you hear about a two degree rise Celsius, you know, like 3.6 degrees
00:30:20.760 Fahrenheit or a four degree rise, or even in the worst case, and you know, an eight degree
00:30:26.660 rise. I mean, if you told me, you know, 30 years from now, my children will be living in
00:30:31.520 a world that is on average four degrees Celsius warmer. It's not immediately obvious why that
00:30:38.460 would be a big deal. You know, if you don't like the heat, you just move further north,
00:30:42.580 right? You just, you know, Canada is going to be great. What are the likely effects of these
00:30:48.620 changes in temperature as, as we go up in increments of two, four, and six degrees Celsius?
00:30:54.880 Well, I think this is a very good point. You know, first of all, obviously the rest of the
00:30:58.400 world talks Celsius and whereas Americans have, you know, in their mind that their temperature,
00:31:05.820 uh, gradations are, are based on Fahrenheit. So I, you know, I think it is better to talk about
00:31:11.820 Fahrenheit. It's still a small number, uh, you know, 3.6 degree Fahrenheit, um, is, is indeed
00:31:19.200 widely viewed in the side of the community and, and by essentially all the major governments in the
00:31:25.620 world, except our current one as a threshold beyond which climate impacts be moved from being dangerous
00:31:33.340 to being catastrophic at a very rapid rate. Um, now you can look at it a couple of different ways.
00:31:40.920 Uh, one of which is that the average temperature going up pushes the extremes up, uh, much faster.
00:31:50.380 And I have a chart in the book that shows that if you can visualize a bell curve in your head,
00:31:57.660 where at the very right side is that tail where you get the monster heat waves that really are
00:32:05.600 devastating to people in agriculture or the monster droughts or the monster super storms.
00:32:10.920 Um, there, they are a teeny fraction of the area under the bell curve. But if you now visualize that
00:32:18.840 bell curve shifting a couple of degrees to the right, all of a sudden, what had been very infrequent
00:32:25.460 events, all of a sudden, all of a sudden start to become quite frequent. Um, and that's why you hear
00:32:31.620 that like a super storm Sandy, which might be a once in a thousand year storm is now actually
00:32:39.720 under a once in a century storm. And in fact, Sandy was followed hurricane Irene, which was also
00:32:48.340 at the time of once in a century storm. And so you see, you know, you can't, you know, storms that used
00:32:54.520 to be once in a century, once in 500 years, if they're now coming every few years, you know,
00:32:59.540 it's because we've changed at the, at the high end of the far end of the bell curve, the frequency
00:33:04.900 of the really rare events. And historically it has been the really rare events that have done most of
00:33:11.820 the devastation in the history of hurricanes. It has literally been seven or eight or nine hurricanes
00:33:19.660 that have done half of the damage. You know, Katrina and Sandy, these are the two most destructive storms.
00:33:27.040 Um, and so they're outliers. So, uh, part one, the reason we worry about this is we're very concerned
00:33:33.760 about the outlier events because they're the true catastrophes. Secondly, um, you know, when you look at,
00:33:42.000 let's say, super storm Sandy, um, one of the things that warming changes is sea levels.
00:33:47.520 And as you raise sea levels, every storm that you see is going to have a storm surge, which is higher
00:33:55.060 and higher because it's the underlying, uh, uh, average sea level, uh, keeps going up. So, um,
00:34:03.440 you know, you get that impact of whatever the weather was going to be. Now you have global warming on top
00:34:10.560 of it. That's why, for instance, El Nino years, which, which are, you know, years that have freaky weather
00:34:16.800 and are slightly warmer than usual, they tend to be the hottest years on record because the,
00:34:21.720 the, the small amount of, uh, the extra regional warming from the El Nino is put on top of the
00:34:28.800 global warming trend. Now, you know, we've had, uh, 2014 was the hottest year on record and then 2015
00:34:34.840 beat that easily to become the hottest year on record. And then 2016 beat that. So we, you know,
00:34:40.580 we've been seeing unprecedented, you know, uh, uh, uh, records in warming and 2017 is on track to
00:34:49.680 probably be the second warmest year on record, but the hottest year on record without an El Nino.
00:34:56.220 So we're, we're starting to see the point is we're starting to see levels of warming that you
00:35:02.320 normally only see during extreme years be the normal weather. And, and so that's where, and
00:35:11.020 that's, in other words, the climate is changing. And that's what I try to tell people, for instance,
00:35:15.800 when I talk about drought, you know, you can look at the California drought, which lasted five,
00:35:21.320 six years, and that was the worst drought in a thousand years. But the point is that as you make
00:35:28.220 the average rainfall a little less and the average temperature higher, then suddenly that type of
00:35:35.880 drought becomes a 10 year drought or a 20 year drought. And instead of it happening every hundred
00:35:43.620 years, it happens every 10 years. So, um, that is one, you know, uh, obvious thing that, that is why
00:35:53.620 even small temperature changes can have a big impact. Just by the way, I mean, another analogy,
00:35:58.220 people use is, you know, uh, if you imagine a planet to be like a human being, it's designed,
00:36:05.640 you know, we, we spent 10,000 years at a relatively constant set of, of weather patterns over time.
00:36:13.440 The climate didn't change very much. Billions of people have chosen where to live based on their
00:36:19.580 knowledge of, is it too warm here? No. Is there enough rainfall to sustain life? Yes. Is the sea
00:36:27.800 level endangering us? No. So the point is we've literally 8 billion people are living in places
00:36:35.880 that they chose to live on, on, based on a relatively stable climate. You now add a few
00:36:41.380 degrees to that. And it's literally like adding a few degrees Celsius or, you know, or, or, or twice
00:36:47.720 that Fahrenheit five degrees, let's say Fahrenheit to your body temperature. So our entire body
00:36:55.060 temperature is constructed around 98.6. And we have mechanisms in our body, as I'm sure, you know,
00:37:01.000 to regulate that temperature. And if you start going outside of that bounds, it means something is wrong.
00:37:07.480 And if it stays outside that bound for a long period of time, it has dire consequences. Well,
00:37:12.620 the same is true for the climate. You know, if we could, if the planet warmed two degrees and
00:37:17.700 stopped, then we would adjust to that. But that still doesn't mean that the 8 billion people who
00:37:25.040 live where they do now wouldn't have to move, you know, a billion or 2 billion people moving,
00:37:30.780 you know, this is a catastrophe, right? I mean, we saw what two or 3 million refugees from Syria
00:37:38.140 turn global politics upside down. Well, let's talk, let's talk about that for a second. The,
00:37:44.960 the, why people would need to move, I guess, two obvious reasons come to mind. You're talking about
00:37:50.440 sea level change. So the inundation of certain coastal areas, and you're talking about the dust
00:37:58.420 bowlification of certain areas where we depend upon agriculture to be viable. Perhaps there are other
00:38:05.620 reasons that I haven't thought of. Tell me about certainly those two variables and anything else
00:38:11.800 relevant to, to ranging global politics. Sure. Well, people talk a lot about different
00:38:18.900 impacts. So it's certainly, I would, if your listeners come away from, from anything, I would
00:38:24.460 want them to, to, to think in terms of the, the two most worrisome impacts, um, is, is, uh, yes,
00:38:33.620 dust bowlification turning an area that was, let's say semi-arid, but could grow crops and sustain life
00:38:41.940 into something that's purely arid, ultimately a desert. But in the transition from it being semi-arid or,
00:38:49.460 or near semi-arid to becoming a desert, it's just going to get drier and hotter and, and, and droughts
00:38:56.020 are going to last longer and longer. And, um, we know that, uh, again, we, we have designed an
00:39:05.620 agricultural system of the world in which we, we feed large amounts of the world from relatively
00:39:12.780 small tracts of land. I mean, we have two bread baskets in this country, you know, the Midwest
00:39:18.020 extending to the Great Plains and, and California. Um, even though of course, Southern California is
00:39:23.760 essentially a semi-arid near desert climate. Um, so again, if you just shift the climate zones a
00:39:31.900 little bit, all of a sudden, uh, you, you find that your bread baskets are become, are, are getting
00:39:39.500 these mega droughts, uh, on a regular basis. And many of our crops are quite temperature sensitive.
00:39:46.000 People want to Google, you know, corn and temperature sensitivity. They will learn,
00:39:50.980 you know, a great deal about it. Um, so the point is that yes, um, you know, uh, uh, much of our,
00:40:00.940 our population is fed by an agriculture system that, that truly wants a stable climate, the, the,
00:40:07.800 the, the, you know, talk to a farmer, the thing they, you know, that, that causes the most problems
00:40:12.760 obviously is extreme weather variability, too much rain, too little rain. It's too hot or it's too cold.
00:40:20.120 Um, uh, so, uh, so that's an enormous problem. You know, literally, uh, uh, there are lots of
00:40:27.360 people living in places, uh, where they're not going to have sources of food. And, and by the way,
00:40:34.020 this is also related to sea level rise because many of our richest agricultural areas are deltas,
00:40:41.580 right? The, the, the Nile Delta, um, and the, the, the, the, the low lying areas of, of Bangladesh and
00:40:51.680 Southeast Asia. So you raise sea levels a couple of feet and suddenly the, the, the many, you know,
00:41:01.500 rich deltas that, that, that were, you know, feeding hundreds of millions of people, they are flooded.
00:41:07.340 And of course they're flooded with salt water and that salt water intrusion, by the way,
00:41:12.600 is already happening. As sea levels rise, salt water goes further and further up those deltas.
00:41:19.540 And, you know, if you Google salt water intrusion, you will find that is a mammoth problem already
00:41:26.180 for places like Egypt and Bangladesh and, and the water systems of Miami. Um, so part one is,
00:41:36.080 uh, are you going to be able to feed? I mean, we're going to have 10 billion people in mid-century.
00:41:41.720 And I, I wrote an article for nature on dust bowlification, just titled the next dust bowl
00:41:46.340 saying the biggest threat facing humanity is how are we going to feed 10 billion people
00:41:52.780 when we're moving in a rapidly changing climate to a world that has less potable water, less arable land
00:42:01.540 and, and, and much more intensive droughts and super storms. So, you know, that is problem number
00:42:11.060 one for billions of people and the choices that they've made where they live now. The second is
00:42:17.520 sea level rise. Uh, people, you know, most of the population of the world or half the population
00:42:22.900 of the world lives within, you know, 50 miles of the ocean. Uh, people like to be near water. Water
00:42:30.040 makes, has made trade possible. Your, most of your major cities, uh, are near waterways near the ocean
00:42:37.080 historically, uh, and even today. So, um, we have, you know, uh, billions of people, uh, you know,
00:42:45.140 and so we have hundreds of millions of people who live right on the ocean, you know, and in places
00:42:50.680 like Bangladesh and even places like, you know, Miami and Louisiana and Norfolk, Virginia, or even
00:42:56.980 Los Angeles. Um, we have staggering amounts of people who live where they live because sea levels
00:43:05.460 have been, uh, you know, until recent decades, pretty damn stable. And we're now moving to a
00:43:12.060 situation where we, we are, uh, uh, where the worst case scenarios of sea level rise appear to be the
00:43:20.080 ones that we are facing. And if you were to have a leading expert, a glaciologist expert on Greenland
00:43:26.740 or Antarctica, um, they would tell you that the, the, the great ice sheets are melting much faster
00:43:33.820 than anyone thought. And that we may be much closer to tipping points beyond which we can't stop,
00:43:40.040 uh, them. And therefore we, uh, we look to be headed to what used to be, uh, the worst case
00:43:49.020 levels of sea level rise are now pretty much the business as usual projections and talking about
00:43:54.980 three, four and five feet. Um, and you know, if you, you can go online and find, you know, uh,
00:44:02.460 programs that allow you to look at the coast of the world coast of different cities under three,
00:44:07.660 four or five feet. But I can tell you that all of South Florida, if you've been there, you know,
00:44:14.640 how flat and low lying it is. It's simply not possible that South Florida is, is habitable,
00:44:22.240 uh, uh, at, you know, uh, by the end of the century under those scenarios, but the same is true
00:44:28.160 of Bangladesh and the same is true of, you know, uh, uh, lots of places in this country and lots of
00:44:34.160 places around the world. So again, we are talking about places where hundreds of millions of people
00:44:40.160 live are simply going to be either underwater or they're just going to be routinely drenched
00:44:46.580 in storm surges. I mean, after all, you don't, you know, you, you, you know, we don't live in
00:44:51.800 places that are, you know, routinely dunked by storm surges, but all the storm surges are on top of
00:44:57.480 the sea level rise. So we don't, you know, no one lives, I didn't say no one, but we don't live
00:45:02.160 right at sea level rise, right? Cause you have the tides and you have storm surges. So yes, the kind
00:45:09.160 of withdrawal is starting to happen, you know, is going to be sped up. And so we are going to end up
00:45:15.140 with a hundred serious worth of failed states, inundated areas and, and refugees. That's,
00:45:25.420 that's where we're headed towards. And that's of course why the Pentagon is incredibly concerned
00:45:31.980 about climate change. And, and the Pentagon has been issuing report after report saying,
00:45:37.120 you guys, climate change is going to become a major driver of civil conflict. Um, as people fight
00:45:45.780 for scarce fresh water, as people are forced down their homes. If you'd like to continue listening
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