Oct. 5, 2022

Ep102: Prof. Chris Rapley "Climate Science, Caveman Brain"

Professor Chris Rapley CBE is Professor of Climate Science at University College London’s Department of Earth Sciences. He served previously as Director of the British Antarctic Survey and of the Science Museum, and is a passionate and plain-speaking advocate for Climate Science.

Professor Rapley is a Fellow of UCL and of St Edmund's College, Cambridge, a member of the Academia Europaea, Chair of the European Science Foundation’s European Space Sciences Committee, Member of the Advisory Board of the UK government’s Clean Growth Fund, Patron of the Surrey Climate Commission, a member of the Science Advisory board of Scientists’ Warning, and a member of the UK Parliamentary and Scientific Committee.

His previous posts include Directorships of the Science Museum and British Antarctic Survey, Chair of the London Climate Change Partnership, President of the Scientific Committee on Antarctic Research, Executive Director of the International Geosphere-Biosphere Programme, and founder and Head of UCL's Earth Remote Sensing Group. He was Instrument Scientist on astrophysical and solar sounding rocket payloads, of the Bent Crystal Spectrometer on NASA’s Solar Maximum Mission, assisted JPL with the Cassini RADAR instrument, and led numerous ESA studies on the use of radar altimeters to study the Earth. He was Chair of the International Planning Group for the International Polar Year 2007-2008 and Chair of the ESA Director General’s High-Level Science Policy Advisory Committee. 

In 2014 Prof Rapley and the playwright Duncan Macmillan wrote the acclaimed play ‘2071’ which Prof Rapley performed at the Royal Court theatre and in Hamburg and Brussels. More recently Prof Rapley was the Science Consultant on BBC1’s ‘Climate Change – The Facts’ presented by Sir David Attenborough, and the three-part BBC1/PBS series on Greta Thunberg. 

In 2003 Prof Rapley was appointed CBE by Her Majesty the Queen.



Click here for Edited Highlights


Michael Liebreich Hello, I'm Michael Liebreich, and this is Cleaning Up. My guest today is Professor Chris Rapley. Chris started his career as a physicist and X-ray astronomer, and then switched to climate science. He's now the Climate Science Professor at University College London's Department of Earth Sciences. He's also been a Director of the British Antarctic Survey, and Director of London's Science Museum. Please join me in welcoming Professor Chris Rapley to Cleaning Up. So, Chris, welcome to Cleaning Up.


Professor Chris Rapley I'm very pleased to be here, Michael.


Michael Liebreich Chris, let me start with a question I ask everybody. Whereabouts are you? That's not the attic of the Science Museum? Is that your home?


Professor Chris Rapley It's the loft in my home, which is just outside London. Yes.


Michael Liebreich Very good. And I'm here in the studio in my house in London. Let's just start, if you could, by giving us a little bit of an intro to what you're working on, and how you got there. Because we have a very diverse audience, and some of them will know you and be huge fans already, as I am, and some of them may not know you. So let's start with the basics.


Professor Chris Rapley Okay, well, I've had a kind of zigzaggy career. I originally trained as a physicist, so that was my first degree. But I got really interested in space science and became a rocket scientist for quite some time. So I was an experimental physicist, you know, designing instruments to fly on rockets and satellites, initially, to open up new windows on the universe. Provided your instruments survived the ride into space, which some didn't, and then survived the rigors of space, you were pretty certain in those days to get something new and interesting. And so I did that for a while. And then it suddenly struck me - well actually a colleague showed me some interesting data from one of the first NASA Earth observation satellites - and I thought, you know what, turning the instruments over, and studying the Earth from space is going to revolutionize our ability to understand how it works as a system. And you know, there's this word, we use microscope, which is an instrument that allows us big things to study very small things. Orbiting satellites, either geostationary ones or polar-orbiting ones, allow you to see the system in all its glory, glorious unity. So it's like a macroscope, it allows you as a small thing to study something very big and complicated as a whole. And it has, it's completely revolutionized our ability to understand how the planet works. So I did that for a number of years, worked very closely with European Space Agency developing their Earth Observation Program, which is, you know, frankly, the best in the world, there's no question. But then I moved on and ran one of the big international Global Change research programs, where I learned a lot about breaking down barriers of disciplinarity, culture, language, thinking and so on. Then I spent 10 years running British Antarctic Survey, went down to the Antarctic, so not only had studied it from space, but you know, boots on the ground, so to speak. And then spent a while running the Science Museum, which was a completely different proposition; the museum is an amazing, wonderful organization, but it's a venue. And so the question before the house is, you know, what do you do to attract and satisfy your visitorship? So since then, I've been back at University College London, and the question that I've been really interested in is: given the overwhelming evidence that climate change is a problem and a serious one, why is the human response, not on a sufficient scale and pace to really address it? So that's what I've been working on with a really eclectic mix of interesting people for a number of years now.


Michael Liebreich Thanks for that sort of geostationary flyby or whatever you'd call it. Well, it can't be a geostationary flyby, but that flyby, that satellite pass, of your career. And I'm going to take this opportunity actually to plug Emily Shuckburgh's episode because she was one of your, one of the scientists hosted at the Antarctic Survey. I don't know if that was the time that you were running it.


Professor Chris Rapley Yeah, absolutely. And Emily is following a really interesting career. And well, we can talk a little bit about that if you wish to, but yeah, absolutely.


Michael Liebreich  She came on Cleaning Up and talked about her trajectory as a mathematician, and then looking at the modeling of the earth systems, so everybody's got their own trajectory. In fact, that's one of the things that makes Cleaning Up interesting, is to see how this incredibly diverse set of people, from lawyers, to scientists, to mathematicians, to policy wonks to just random folks, have sort of gravitated towards the question that you've finished up with, which is, how do we actually accelerate? How do we internalize what is happening and accelerate action?


Professor Chris Rapley  Absolutely. And it's interesting is that as a natural scientist, I have strayed into areas of academic study that are, you know, so far away from where I started, they're kind of over the horizon. So, it's quite an adventure and a fascinating exploration. But if you do that, you need a good guide. And I've been very lucky to work closely with my neuroscience colleague, Kris de Meyer, who is a brilliant guide as to what 50 years of the Mind Sciences have produced by way of useful insights to address exactly the question we're talking about.


Michael Liebreich  When you said that you've strayed over the horizon, you know, I had, sort of visions of you studying, I don't know, necromancy and astrology. But neuroscience is not that far away. When you talk about the decision, when you realize that a big part of the problem is the humans, then neuroscience, surely is a relatively obvious thing to end up with.


Professor Chris Rapley  I think that's right. And I think what's embarrassing is that, as I say, I started life as an instrument scientist, and your self-esteem and the esteem of your colleagues, is built on a reputation for building wonderful instruments that do amazing things, open up new windows. But being the absolute expert that can instantly look at a data stream, and distinguish between something which is a quirk of the instruments - all instruments have those - and something that might be a revolutionary new insight, you know, in the data. And so it's been something of an embarrassment to realize that my primary instrument, you know, my Mark I Paleolithic brain, was something that I knew very, very little about its strengths and weaknesses. And so the discovery that it operates in certain ways and is brilliant in certain ways, and is fallible, in certain ways... It's been a bit of an embarrassment to discover that so late in life, that's my primary instrument. So I wish I'd known some of these things bit earlier, it would have helped.


Michael Liebreich  Interdisciplinary journeys, I think, are very, very interesting. My own was starting really at high school, with physics, then engineering, and then doing a whole load of micro-economic modeling, which is sort of, you know, quite similar to engineering. But now it's, it's looking at costs and experience learning curves, and so on. I've done finance, and then - and some macroeconomics - but it's kind of reached the point where suddenly... Okay, so then the big problem is policy, and then the big problem after that becomes the humans in the system. And I've now, I don't pretend that I've studied the same amount of neuroscience, but I did a bit of that sort of thinking. And then where I am now is actually biological systems, and the whole nature-based solutions stuff, where I feel that my industry, the clean energy industry, sort of dipped in 15 years ago, got their fingers burnt, wasted a lot of money on next generation biofuels and decided that none of it would ever work. And in fact, our last guest, Jennifer Holmgren, is an example of people who persevere and then these things do start working. And I think they have to...


Professor Chris Rapley I think there's a sort of messiness. I remember that one of the Shell Scenarios, some years ago, had two options. One was blueprint and one was scramble. And of all of the Shell Scenarios, that was the one that resonated most strongly with my view of the world; that is, that we are - many of us academics - are children of the Enlightenment, and we like to believe that there is a linear model by which we gather information and insight, we process it, and we, you know, deliver facts and information that allow sensible decisions to be made. But the truth is that humans really don't operate that way. And a scramble, which was a much messier scenario, is probably, I felt at the time, was much more likely to be the route that humans actually take. And once you confront that, once you just sort of accept that that's the way human affairs tend to historically roll out, then you can start to address it. Just one thing on the interdisciplinarity: in academia, shifting from one specialism to another is quite a dangerous thing to do because you establish yourself as a greater and greater expert of less and less... I'm sorry, I'm being a bit cheeky, but you understand what I mean. And if you do a big jump, and I've done that, you do pay a price, in terms of, you know, number of publications, and so on, the ability to establish yourself. And so there's a bit of a dip. But the benefit is that - I've done this several times - and what you find is that you bring with you tools and insights and knowledge, that are new to the new field, but that are well understood in the other field. So often, you can cross fertilize things in a very productive way. So for those that are thinking of zigzagging around, there's a risk, but there's a huge, huge satisfactory benefit.


Michael Liebreich I think I'm a testament to that, because, you know, I actually never became as deep a master as you in any individual area. I jumped around, I became a jack of all trades, master of none, rendered myself completely unemployable. So I had to start New Energy Finance, and create a new space where I could be expert, bringing little bits from skiing, and, you know, hanging out with glaciers and mountains, and a little bit from physics, a little bit from this, that. It definitely works, but it is, it's very uncertain, it's destabilizing, because we're expected to follow that very programmatic course.


Michael Liebreich NASA used to talk about the T-shaped person. They said, it's all very well having the crossbar where you have an eagle-eye view, or a helicopter view, of the problem domain. But unless you've got the deep... unless you can bring something to the party, and actually deliver something, you're not very useful. So they were always looking for people who are T-shaped. And of course, just being skilled, but not having the ability to look around and see where your skills might be best applied, that's not terribly useful, either. So the T-shaped person is quite an interesting concept.


Michael Liebreich I think what it is, you now need lots of stems on your T, because one will become obsolete... But remind me, it was a scramble and what was the other scenario?


Professor Chris Rapley Blueprint, that's the much more planned approach.


Michael Liebreich I love it. Of course, I've come across those using words that Shell would never use in their scenarios, which was the Global Plot versus the Cock-Up theory. The Scramble, you know, otherwise known as the Cock-Up theory, does sort of resonate, it does mirror a lot more of what we what we see out there. I want to ask you about one area, one thing that you've dipped into, one of the over-the-horizons, is that you became a playwright?


Professor Chris Rapley Yes. Oh, well, that was a really interesting experience. I mean, I should say that I've always felt that... My father was a good storyteller, and I've always felt an obligation to tell people about the science that I do, or that we do. Partly because it's pretty much 100% paid for by the public purse - I think there's a moral obligation to tell people - but it's enlightened self-interest. And what I've always found is that this myth that people aren't interested in science is completely wrong, it just depends on the way you tell the story. And, you know, as often as not, even the most hardened, anti-intellectual, if you tell them the story in an interesting way will end up saying, 'oh, that's interesting, tell me, more that sounds really interesting.' So I've done a lot of that, and so over the years have tried to tell the story of climate change. And we must come back to this, because there's a classic way that the story is told, which leads to problems, I think, many of the problems we've seen. But I was looking for something new, and, again, one of these chance encounters, you know, somebody I know heard that I was... They invited me to give a talk and in the coffee bar afterwards, I said, I'm looking for something new, I'm thinking that theatre, you know, with all of the bundle that goes along with theatre - you know, you suspend your beliefs and so on, you indulge, you know, you paid for your ticket, so you go to have an experience. And I thought, you know, an experiential delivery would liberate me because I could take off my formal academic cloak, so to speak. So, you know, the deal was, if you want the formal, IPCC-based scientific talk, with all the rigour and all the rest of it, I can deliver that. But in the theatre, I can take that off, and I can give you a fireside chat, where as a human being and as a member of a free society, I'm allowed to say what I think. And you know, if that strays a little beyond what I would feel comfortable doing in a lecture, well, so be it, take it or leave it, I'm allowed to have opinions. So I worked with, with Katie Mitchell, who's a brilliant theatre director, and with Duncan Macmillan, the playwright. And what was extraordinary was that it took the three of us. It took my science input, Duncan's capacity to draw out a narrative arc in simple language that took people on a journey through this story, and Katie and her team's ability to present it in a theatrical, experiential way. And it really worked. It received a lot of attention at the time. Some of the critics absolutely hated it, they canned it, because they didn't really understand what we were trying to do, but others got it. And Michael Billington in particular, gave it a five star, we sold out. What was interesting was that, you know, I think I did 14 or 15 performances - they had us come back because it had sold out. But the final performance was in Brussels, funded by the European Climate Foundation, and that was to an invited audience of 400 people from the Brussels bubble - so, the Commission, the Parliament, the lobbyists and others. And it was in the run up to COP 21. And it caused a real stir, generated an interest, you know, 'what is this climate scientist doing sitting on stage, you know, giving us this theatrical performance, or at least this fireside chat?' And I had a letter afterwards, from ECF, saying that they had had feedback from within the Brussels system, saying that it was hugely timely, and it triggered a whole discussion about climate change, just as they were beginning to formulate their approach to the Paris Agreement. So in a small way, it just steered history a little bit.


Michael Liebreich So then that's a great addition to a sub-genre of Cleaning Up, which is interviewing, talking to people who are very, very involved in the Paris Agreements. So we've had Teresa Ribera, who probably would have been at the European Climate Foundation, at the time that you did that, and is now Deputy Prime Minister of Spain. We've had Christiana Figueres, we had Todd Stern, the US negotiator, we had Amber Rudd, we had Catherine McKenna. We've had all sorts of people who peripherally... so now we've got a little addition to the genre there. And of course Laurence Tubiana, who is now running the ECF European Climate Foundation, but was at the time the French climate ambassador.


Professor Chris Rapley Well, Connie Hedegaard was there. We had some influential people there, and it had, in its own small way, it had its impact. The book that we published has sold pretty well. It only takes, you know, literally 50 minutes to read. And it combines the simplicity of narrative that Duncan was able to introduce with a degree of rigour that I tried to ensure that you know, it was factually correct.


Michael Liebreich You've just reminded me I need to get the great Connie Hedegaard onto Cleaning Up, we'll make a note of that, she's absolutely tremendous. Just tell me, within that, in that way, did you... because you're saying we're in 2071? Presumably, I've not seen it? Did you choose one scenario and say, 'right, well, this is how it turned out.' It's really, really, really bad. Or did you jump between scenarios? How did you deal with the uncertainty?


Professor Chris Rapley Essentially [we] laid out the story both from what convinces me by way of evidence, and then backed it up with what convinced the IPCC at the time - I guess AR5 had come out at the time. So, you know, we gave my opinion then said but by the way, there's good reason for this. And then we got on to what can we do about it, and it was really a kind of technological and good news story about look, a lot of people are taking this seriously. I mean Laudato Si had just come out, Modi had made commitments, you know, there was a lot going on at the time in the run up to Paris. And so it tried to focus on a good news activity approach to... You know, we know we've got a problem. You can argue endlessly about how big and exactly what shape it is. But we know that we've got to try and keep this stuff in the ground. So what is the technological transition that we need to follow? And what are the political decisions that need to be made to help that technological transition take place, so that in the future, we leave a legacy of a reasonably decent planet for our grandchildren and 2071 was chosen because my 10-year-old granddaughter at the time will be the age I was when we wrote the play in 2071. So she was somebody I could focus on as an individual who will be confronting whatever we've left by that time. So in many respects, we ducked... We had long conversations about should we get into the politics, shall we get into the economics. And I said, you know, I'm not an economist, I really don't have any sound basis for sounding off on these areas. So we actually steered clear of a number of the tricky areas. But what we were trying to do was get a discussion going, get a debate going, open it up. Remember, in 2014, when we wrote the play and delivered it, climate science was still, climate change, was still something of a taboo subject. You know, if I was at a dinner party, and people said, what do you do for a living? And I said, I'm a climate scientist, they would all look embarrassed and go 'the broccoli looks nice, isn't it?', sort of change the subject. It's different, now. It's different now. If you say, you're a climate scientist, people say, 'Oh, well, can you help me on this issue?' But it was different then.


Michael Liebreich I'm glad to hear that you're getting more varied and more engaged invitations to dinner parties. You mentioned one thing, I'm just going to clarify - you mentioned Laudato Si - and that was the pope who produced an encyclical saying that we need to deal with climate change. And I enjoyed it enormously because it meant that I actually learned how you say long duration storage and renewable energy in Latin. And I'd very much like to get the Pope on to Cleaning Up, that might be one step too far, even for my network. But where I was going with the scenarios, is, you and I have actually talked about what the IPCC says and which scenarios are plausible. And there's a kind of, there's something of a ghost at the wedding here on this episode, which is Roger Pielke, Jr. and I did an episode with him. It was one of the last episodes of season six, so that would have been just before the summer. I did an episode with him. And there's also those of you who can see on the video, if it's visible over my shoulder, there's his book, The Honest Broker, which is about the role of science, and you've kind of almost like cross-dressed between different roles of the scientist in this debate, which has been really, you know... I think we'll come back to the role of the scientist. Where I want to go, though, is maybe take this opportunity, since we've got you; there's now AR6, there's another IPCC report. What does it say? And, you know, are you looking at it and going well, we are on track not to get some of those worst-case things that I was worrying about? Is it getting worse? Is it getting better? What does AR6 actually say?


Professor Chris Rapley Well, I mean, for me, I just quoted: it is unequivocal that human influence has warmed the atmosphere, ocean and land, widespread and rapid changes have occurred in the atmosphere, ocean, cryosphere, and biosphere. So, you know, for a long time, we were waiting for the signal to creep out of the noise, because, you know, there's obviously natural variability in the climate system. And I think AR6 just hammers the nail very, very firmly into it and says, look, you know, let's not argue about this anymore, you know, we know we've got a big problem. And then, of course, the Working Group III said, it's now or never, if you want to limit global warming to one and a half degrees, without immediate and deep emission reductions across all sectors, it will become impossible. So there's this concept of the carbon budget, and the fact that if we don't keep - what is it - 90% of the coal in the ground and 60% of the oil and gas, you know, if we don't really get to work on that very quickly, then we're going to blow the one and a half degrees, quite probably. And I think I'm amongst quite a large community of climate scientists that's pretty skeptical that we're going to keep under one and a half degrees. I'd like to come back to that one and a half degree - the use of a single average temperature to characterize this whole problem, which I think is extremely... has proved to be very unhelpful, but that's a bit of another story. And so then Antonio Guterres, of course, the UN chief said - slogans are the in-thing in politics these days- he characterized it as code red for humanity, you know, we've really got to pull our fingers out and get on with it now. And I have a lot of sympathy for that. But I watched Roger's episode and, and... I originally came across Roger - well, he came across me - way back in 1994, when I took over the International Geosphere-Biosphere Programme, and he wrote me a letter saying, you know, congratulations, I hope you do a better job in IGBP than the US Global Change Research Programme did on acid rain, and atmospheric... clean atmosphere. Because he said what happened there was that the community was engaged with a very substantial funding package. And it did a whole bunch of research, but it didn't think through the synchrony necessary, or the rhythm of the climate science research - what it takes to go through a huge program, do a whole bunch of research and then come to a set of conclusions, which are policy relevant, not policy prescriptive, given the legislative rhythm. And his point was that the legislative rhythm was such that decisions had to be made in the legislature before the final results emerged from the US Global Change Research Program. And he was very critical, I think with some justification, that the climate science community and the other world of policymaking, were not synchronizing themselves, and you know, who was to blame and all rest of it, I don't care about, but he said, try and do a better job. And I thought, you know what, he's got a very good point. And so when Jane Lubchenco famously wrote her paper, which was called A New Social Contract for Science [Entering] the Century of the Environment... There are occasional papers that come out that just grab you, you just read them and you go, wow, yes, got it. You know, absolutely, wish I'd said that. And Jane's point was that it's all very well being a pure scientist, which is one of Roger's four roles for climate scientists, where you investigate in a pure and honest and impartial way, the functioning of the climate system. But if you're justifying that at all, in your words, as being policy-relevant, then you really need to look over the wall and figure out how you join the two things together. And there have been plenty examples where that didn't work very well. The IPCC, I think, has learned a great deal and is an exemplar, up to a point of how you deliver stuff to policymakers, which they may find useful. But I don't know if you've come across Simon Sharpe, somebody I would recommend - he's just got a new book coming out, which I really recommend, called Five Times Faster. And I've seen a preview of it, and it's brilliant. Simon is brilliant. But Simon's point is that there are still plenty of examples where the climate science community operates under its own rules and its own insights as to what it thinks are important. And he makes the point that climate science for example, and climate scientists, are much more comfortable delivering prognostications about the best estimates of some variable like temperature, or rainfall, or sea level rise or whatever it is, whereas the decision-maker, a strategist, who's actually got to save London from, prevent London from being flooded, actually wants to know when the probability of a certain threshold - the critical threshold, the top of the embankment for example - is going to be violated at some level. You know, when is the likelihood of the embankment being overtopped going to reach the one in 1000-year event, which I think is the fiducial requirement on people who are tasked with defending London. So it's all very well telling them what the best estimate might be - that alerts them to the fact that there might be a problem - but they need to know something different. And he points out that if you look at what the IPCC delivers, it still tends to give best estimates, rather than best estimate of probabilities crossing critical thresholds, which is what decision makers really need to know.


Michael Liebreich Let's just pause for a second and give the four models that Roger Pielke has in his book, The Honest Broker, because I think that they are incredibly useful to sort out and dive into those issues. So, he talks about the idealized model, which is the pure scientist, and the example he uses is he says, [if] you're trying to choose a restaurant, the pure scientist will tell you what the nutritional values are of the things on the menu, and then say, 'well, there you go - I'm a pure scientist, you do with that what you will.' The second one is the science arbiter, who will say, 'ah, this one's got more nutritional value than that one', or might try and actually provide a sort of comparison but then says, 'it's up to you.' You've got the issue advocate who thinks you ought to be a vegan, and will tell you why the vegan restaurant is better than any other restaurant because they think you ought to be vegan - for your own good - but that's maybe an explicit issue advocate. Roger's now got a sort of fifth category, which he's very scathing about, called the stealth issue advocate who doesn't say that they are coming from a particular perspective, but they just tilt what they say, so that it pushes you. And then there's the honest broker who says, 'okay, let me kind of get into your head as a policymaker.' He's making this decision about restaurants or flood protections and the honest broker is somebody who gets in your head works out, what is the decision you face, and then tries to assemble the information you need, perhaps also opening up other options that you didn't think about because they are after all, the expert. And I suppose for me, those four models are very, you know - the pure scientist, the science arbiter, the issue advocate and stealth issue advocate, and then the honest broker - that's very helpful for thinking about how scientists should really operate in a policy environment.


Professor Chris Rapley I agree. And I really admire Roger's book, and I bought the first and the second editions, and they've been very influential in the way that the Climate Action Unit at UCL, which we'll come on to, has been thinking. So it does seem to me that that last category... Well, first of all, all four categories are fine, as long as you tell people and are clear in your own mind which role you are playing. They all fit, and we all play those roles, mix and match them at different times. The one that Roger is concerned about is the stealth advocate, where, you know, I don't inform you that my brother in law owns the vegan restaurant that I'm recommending, I may not even have noticed that that has an influence on me so...


Michael Liebreich Just to be very clear, he doesn't worry about the vegan restaurant, he worries about the issue advocate who, who tries to persuade everybody that the world is about to end because they think that's the only way to get action on this issue. And it happens also to feed their own career, their own research grants and so on. And he's very scathing about that.


Professor Chris Rapley Yes, well, and there are others who've talked about - I'm trying to remember the phrase - the iron bowl or something where, clearly, it is absolutely the case that climate science has received more funding because it is seen to be of societal relevance, than if it had just been a pure intellectual exercise. So of course, there is a danger that some people either inadvertently, or even deliberately, might over-egg the case in order to pursue funds, career, fame, fortune. It's an accusation that has been leveled at the community by those that are of a different opinion about climate change, because attacking the player, not the ball is often an easier thing to do. So it is a danger that needs to be observed. And in a report that we produced in 2014, one of the final conclusions was that everybody who's in this field needs to retain humility, and to constantly have a little mirror in front of them, and ask themselves the question, well, wait a minute, why do I believe that? Why did I say that? You know, am I really justified in doing... Am I confident? And so constantly be introspective...


Professor Chris Rapley Like Roman emperors used to have somebody - the jester I think it was - saying, 'remember, you are mortal, remember, you are mortal.' So, this would be somebody saying, 'remember, you're a scientist. Remember, you are a scientist.'


Professor Chris Rapley Exactly. You know, I've run big organizations, and I've always welcomed people who stand up and say, 'I think that's a daft decision you just made there, Chris, and this is the reason why,' because then you can have a discussion and decide whether you agree with them or not. Surrounding yourselves with 'yes' people is incredibly...


Michael Liebreich Is it really as benign as that? Because I have online been very vocal about the use of scenarios that I, as an energy expert, know are completely implausible. So there's the extreme scenarios, the 8.5 watts per square meter, RCP 8.5, now SSP585. And yet, and they are implausible. I mean, we know, and Roger talked about it in the episode, that there's not enough coal on the planet that can be burned to get there. We're not tracking that even the UNFCCC is now producing output that shows that the scenario that the US Climate Assessment used as the exemplar of success, the 4.5 scenario, is now actually where we're headed. And you and I would think that's awful, and we need to get to 2.5 or 1.9 or wherever. But still, August this year, NOAA, [the National Oceanic and Atmospheric Administration] is publishing findings saying that when it comes to fisheries, we need to test their viability against RCP 8.5. And I mean, at some point, you just have to believe somebody's doing it on purpose, rather than really having missed the last - I don't know - 10-15 years what's actually happening on trajectories?


Professor Chris Rapley We're unpacking a whole bunch of messy issues here. So, let me try and pick a way through this. I disagree completely if somebody is either inadvertently or genuinely dishonestly misusing some piece of information, or not information in this arena. And that needs to be called out. And you know, Roger does a good job of that. I think it's a shame that Roger’s interventions have become so polarized; I don't think it's his fault, necessarily. But it's much better to have an adult, sensible, calm conversation about these things that tend to divide into the good and the bad, and the black and the white. It's so easy to, you know, demonize people. And it's very, very, very unhelpful. So just setting that aside, I'm quite happy to see extreme scenarios looked at, because they're a tool. And the value of any... A tool may be a good tool or a bad tool. Even if it's in principle, a good tool, it can be mishandled by the artists that wields it. So you've got to have both things. You've got to have smart artists and some good tools, the best tools you can, to try and open up some thinking and figure out where you might go next in in a world of uncertainty. I mean there isn't a single part of human activity that isn't plagued by uncertainty, because we don't know what the future is. But let me just come back on this. So I was very impressed by the book, Fukushima, which is, I think, probably... The authors are three physicists, I think there's a little probably a little bit of bias, I think that they started out with a bit of a negative view towards it. I don't know, I'm speculating. But what I thought was interesting there was that they pointed out that through the long history of the nuclear power industry, there have been scenario exercises to figure out, you know, what happens to this, you know... I know Westinghouse power station, if you install it on an earthquake zone, you know, all of that stuff. And the point about Fukushima was that there comes a point in any scenario analysis, where those doing the scenario kind of go, you know, I think we've gone far enough, you know, we can imagine even more exotic combinations of factors. But if we go to the board of directors with that, they'll think we're ridiculous. So there is evidence of a tendency to pull back a little from extreme scenarios. But if you talk to strategists, they will say, actually, I would really like to know what the most extreme set of circumstances might be, even if the probability is close to zero, because it's just useful to have that as a bookend from which we can move back to something which might be more realistic.


Michael Liebreich I reject that analogy, though, because the scenario of a tsunami of that size was not that extreme in the case of Fukushima. In fact, it had been sort of considered, and it's just the preparations for it was where it fell down. It wasn't that unusual. Whereas, if you look at the extreme scenarios of, you know, the RCP 8.5 scenario, it is in my view, with my knowledge of the energy system, not just... it's not a question of well, it's 1%, then maybe we should do it. It is like saying, it's the equivalent of saying, you know, I want to research how cats brains respond to 5G, electro-magnetic loads, so I'm going to put the cat in the microwave. Because that's going to give me lots of good research data. And then afterwards, presenting that as in any way a realistic, plausible scenario for what 5G might do to a cat is completely... I'm afraid... I mean, I don't want to use words like dishonest but that is sort of what's happening in some parts of....


Professor Chris Rapley First of all, I'm not an expert and to be you've done a lot more work looking and unpacking RCP 8.5, and the more modern, the more current version of it than I have. And I hear what you say, and it is certainly the case that - and you raised this I think in the conversation with Roger - you say, who is the climate scientist? I mean, there is nobody -  nobody - who really understands in depth the whole jigsaw that is climate science. How could they possibly? And so there is a momentum that tends to build up on certain elements of the story, which I think in this case is probably unhelpful and unjustified. And I mean, if we could go right back to the very beginning: the use of a single global average figure to characterize climate change is incredibly unhelpful. It is thermodynamically nonsense, because the way thermodynamics work... if you heat something up, the rate at which it radiates away as heat is completely nonlinear. So doing a global average of temperature data from around the world is physically meaningless. And we know that the land is warming faster than the ocean...


Michael Liebreich Exactly! I've always found that using the air temperature, using - whether it's 1.5, whether it's two, whether it's whatever - when 90% of the heat goes into the ocean. It's just extraordinary.


Professor Chris Rapley For my money, the person I admire in this respect is Kevin Trenberth, who has been talking about the energy imbalance of the planet for decades. [He's been] A voice in the wilderness, because actually, as a physicist, what is going on here, we have upset the energy balance of the planet. The planet intercepts heat and light from the sun, the energy goes mainly into the ocean, a bit into the atmosphere, a bit into the land, it drives the motions of the fluids, because there's a temperature difference between the equator and the poles, and then the earth radiates that heat away into space. And in its long, long history, the balance between the input and the output has been equal to many decimal points. What we have done by upsetting the opacity of the atmosphere to infrared radiation, and a few other things, is that we've upset that energy imbalance. So as we speak, the Earth is accumulating 20 times as much energy as humanity generates each day to run the entire energy system of the world. You know, if you say, by the way, I've meddled in this hugely complex system that, however hard I try, I'm never going to fully understand, and I've upset it by a degree, which is an order of magnitude more than the thing I did in the first place, you're going to say that sounds not a very smart thing to do.


Michael Liebreich As a physicist, I'm just going to come at you with one question. It's 20 times... the perturbation is 20 times the energy we use for our economy. What is it in terms of percentage of incoming and outgoing energy, because it's a few... it's a watt and a half per square meter.


Professor Chris Rapley I think it's 0.3%. That's the figure I'm remembering. I have to check it.


Michael Liebreich Because in a sense, that's a more... I don't want to use the word honest. But that's a more... we've got it out by point three, and of course, it's going to get worse. I mean, it's not going to go back by itself. That's the main point...


Professor Chris Rapley But the point from my physicist brain is that the aim should be to get it back to zero. That's what we're trying to do. We're trying to get the energy imbalance back to zero, so the planet will warm up, so that in the end it forces more heat to be radiated away to space. And if we stopped upsetting the atmosphere tomorrow, it would take a while to do that, you know, 30, 40, 50 years, and the consequences will roll out over 1000s of years. But unfortunately, it's chasing its tail because we keep pumping more stuff into the atmosphere. So it's, it's never going to catch up as long as we keep doing that. So, just in terms of visualizing what's going on, getting the energy imbalance to zero seems to me to be just a clearer thing to do, than to talk about trying to avoid going through certain temperature thresholds.


Michael Liebreich And what's your best estimate then of where we are going to go? Because, you know, you've said one and a half - I gave up on one and a half degrees, probably around, oh, I think probably around 2015, even before. I always thought that was nice to have it aspirationally in the Paris Agreement, but I'm more on the kind of... I think we can do two, I think we can go well below two, 1.8 something like that, with a lot of effort. But it was very interesting... I also thought until I did my deep dive into RCP 8.5 in 2018, I thought we were heading for three degrees or more. I now don't think that, I think we're below that. What's the answer, O, great climate professor?


Professor Chris Rapley Well, I mean, I'm afraid I end up just looking at reliable sources on the web, like you do. And, you know, Carbon Tracker and so on, I think do a good job. I mean, it looks to me, based on the commitments and the promises, that I think we probably are going to go through two degrees. I think we're heading for 2.3, 2.4, something like that. But, remember that it's a probability distribution; we might strike lucky. And maybe the system is less sensitive than it might be, and so we might be at 1.8, as you say, but equally, we might be unlucky, and we might end up with, you know, three, four degrees, it's not out of the question. I think... what's the figure, isn't there's still a 5% chance it could be five degrees or something? I mean, you wouldn't run a business, would you, based on the hope that the system will turn out to break in your favour rather than break against you?


Michael Liebreich I don't think it's 5. I think it's 5% of greater than 3.5. Look, it's catastrophic. And there is something very interesting, that struck me. The first episode of this season, I talked to Bill McKibben and I went back to his book, The End of Nature, 1989. And it's fascinating to see that the science has actually moved on in terms of these scenarios. Where we're headed, we're not going to end up at five or seven degrees, we're going to end up... you and I are talking about somewhere between two and three. But what's interesting is we're seeing much worse impacts than we thought 30 years ago, at those temperatures,


Professor Chris Rapley Even at 1.1, or 1.2, we can argue about you know, where the pre-industrial baseline is. And that was the point I wanted to come on to. I don't remember anybody predicting, even a few years ago, that Pacific Gas & Electric would be bankrupt, because some of their faulty equipment ignited a fire that destroyed lives and properties in California, and a class action against them has left them with I've forgotten how many 10s of millions of dollars, they're going to have to pump up to compensate the people. So, I'm not saying that climate change caused that; it's an amplifying factor, you know, it's a factor in a story. I just got the book, California Burning, a very interesting read, where, a piece of metal bought in 1902, or something, snapped, and ignited that fire. So it's clear, and this is where I agree completely with Roger, it's a combination of exposure, vulnerability, and the acceleration, the amplification of the situation due to climate change. Now, nobody predicted that. And yet, it is a very real consequence of this combination of factors. So in total, if I had been PG&E, 10 years ago, and had had an inkling that this combination of circumstances could lead to my demise, then I might have panicked a bit and started doing a bit more maintenance along those supply lines. So, the question before the house is, what other things are lurking out there, that we have not imagined yet, the combinations of circumstances that are going to be real in four 5, 10, 15 years’ time? And so, adaptive pathways is one way of dealing with this, but simply recognizing that the black swan is out there. And so being fleet of foot and resilient to as yet unknown threats and circumstances, the unknown unknowns, is something that everybody needs to be engaging on in their thinking, it seems to me. It's very hard, but just recognizing that that's an issue is the first step.


Michael Liebreich I want to talk about Adaptive Pathways because that speaks to the policymaker's needs to make decisions in the face of uncertainty. But I want to talk about attribution studies, because that's an area that it struck me. When I finished my conversation with Roger on Cleaning Up, I felt I hadn't pushed him hard enough. Because, you know, we've got all of these things going on this year: the India-Pakistan heatwave, the European droughts, the China drought, the Horn of Africa drought, then the Pakistan floods. And in each case, the evidence for the climate fingerprint is contentious. And for instance, with the Pakistan floods, which the media has decided was definitely climate, actually, if you go to the famous IPCC AR6, it doesn't say there's going to be really big floods in Pakistan. They do say it about neighboring India, but they don't say it about Pakistan. So what is the state of attribution studies? I mean, how, how accurate can we be with this stuff when it feels to me like it's still quite an early stage of our understanding, and it may be an unknowable problem? It may be just that some of this is, you know, it's so noisy that you really can only tell when it's almost too late.


Professor Chris Rapley Well, Roger makes the point that the way the attribution studies are carried out - and I have huge respect for the for the people involved, Friederike Otto and others - but you are simply comparing a model that's run in one state, without global warming, or whatever you want to call it, against one that has it, and then attempting to look at the difference in probability of something happening, you know, a particular event. I think it's a really, really, really helpful area of research because it does allow you to articulate things in a way that is meaningful to people. But at the same time, I take Roger's point that, let's see that signal emerge out of the data. Let's see - if something's 30 times more probable now, let's see it happen, let's say, 30 more times, but...


Michael Liebreich Is it not also very dangerous? Because let's say Pakistan floods, right? The model didn't predict it, then it happens. So then you go back and you tweak the model, and you say, 'ah, now we've got a model that predicts it.' But that's not really science, is it?


Professor Chris Rapley Well, look... I respect the people who do this, I have a lot of confidence in them, you know, people like Peter Stott and so on, are extremely careful and thoughtful scientists. So, you know, if I have a question about this, there are certain people I ring up and ask, and those people are the players in this particular game. I think it's a young science, but I think it's proving to be a helpful talking point. And I think some of the results seem to be fairly convincing. To be able to say that the Siberian fires, you know, just wouldn't have happened, if we hadn't had the elevation of temperatures up there that we've seen, seems to me to be a useful thing to say. You can then get into, you know, you can do a deep dive into the into all the detail and decide, how reliable that result is, but it opens up a conversation, which a lot of people will find very helpful. The trouble with watching the data, watching the signal emerge from the noise, is that things are happening so quickly that.... We all know that to make a robust climate statement, you probably need 30 years of data, and things are happening on timescales which are much shorter than the 30 years. So there's a problem in terms of keeping up with the data and if you like solidifying the conclusion, on the basis of genuine events statistics.


Michael Liebreich Let me link this back to this question of adaptive pathways, and I think that's the last question we'll have time for, unfortunately, as much as I'd love to continue for another hour. So I was on the board of Transport for London. And I wanted to get into the question of when does the Thames Barrier need to be replaced enhanced, doubled, whatever. And the precautionary principle would say you take the most extreme scenario that you can - the cat frying in the microwave type scenario, the one beloved of my good friend, Richard Betts, who, every so often I have a little tiff with on Twitter. And then you say, well, that's the worst that might happen, so we must assume that and start preparing. And what I discovered was that there was a much more sophisticated process going on in London and in the infrastructure risk management process, which was saying, okay, what do you need to know when? And that strikes me as... In finance, we would call that real options pricing. And we would, we would definitely, I think the finance world, the more sophisticated bits would try and do that. How widespread is it? And is it the right way to think?


Professor Chris Rapley Well, I mean, Tim Reeder was the brain behind the Thames Estuary 2100 plan that the Environment Agency produced, and that was seen as something of a game-changer, and really picked up by others around the world: the Dutch, the Americans in New York and so on. Because there was this conundrum about oh, my God, what will it be like in 2100? What's our best estimate of where things will be? Should we try and manage that level of sea level rise in the Thames Estuary? I mean, you know, worst case of two meters or something like that. And Tim very sensibly said, well, how long, based on what we know now, what we're confident about, how long can we stick with the existing infrastructure, the Thames barrier as it is - and the various options that we're already introducing about flooding various areas to use them as reservoirs when we've got a fluvial event. Well, an event in the Thames and heavy rain, all the combinations. And so, when do we have to make that decision? And on the basis of what we know, at the time, what is the best decision that we can make, recognizing that if we get it wrong, we might want to rather rapidly reconsider? So, if you're going to elevate the embankment by x meters, build the foundations a bit stronger, so that if you've got it wrong, you could quickly add something on top to give you a little bit more resilience. And I mean, that is just such a powerful way... So you're not trying to solve the whole problem in one go, you solve it in a series of steps, which optimizes the expenditure, and optimizes your risk management. So I think that adaptive pathways are finding wide application across a whole load of similar problems now, and it is the logical way to deal with it.


Michael Liebreich It is, but there's a lot of pushback. There's a lot of people who say, well, you know, if it might happen by 2100, we should do it now. And of course, what they don't take into account is there's real resources being spent on these things. This is not free money.


Professor Chris Rapley Yeah. And there's another twist, if I may, given that we're running out of time, and that is that there is a paradox that as you build confidence in something like the Thames Estuary 2100 plan that the London floodplain is well looked after and well protected, at least for the next, you know, 80 years or so, of course, investors put more and more investment into the floodplain. Now, if in the end, the truth is that at some point in the future, the embankment is going to be overtopped, maybe a more sensible approach would be to say, you know what, let's not put all of that investment into the floodplain, maybe we should be investing in moving London to Oxford or somewhere, the north, wherever, somewhere where in the end, the threat does not become existential. Now that's a really tough decision to make. And it's not one that is very popular to raise.


Michael Liebreich Although... maybe Goldman Sachs still builds their new headquarters, but puts it on stilts... And that's a really interesting discussion. It's a shame to leave it there, but I think what I'm going to do is I'm going to ask you to introduce me to the adaptive pathways.... And also, by the way to the attribution studies greatest experts, because I want to get them on this show. It strikes me, having said that finance is comfortable with real option pricing, the people who don't appear to be doing adaptive pathways of any sort is actually the network for the greening of the financial system, and the central banks, who are still trying to think of most extreme plausible scenarios and throw them at the capital markets and see what happens.


Professor Chris Rapley Yeah, well, again, way out of my expertise. But I'm just going to do a final plug, if I may, for the Climate Action Unit, because one of the things that... My colleague Chris has surveyed 50 years of what you might call Mind Science research, in which there's quite a mix. There's a lot of stuff which is arguing, you know, how many angels can land on a pinhead, and there's some really, really useful, powerful insights. One of the insights is that the linear model isn't the way that human beings work. And I mean, Daniel Kahneman characterizes the human brain as a machine for jumping to conclusions, and shows that, you know, we really aren't rational actors; homo economicus doesn't exist, and so on. So what we've tried to do is say, do you know what, framing climate change as a problem, which has been the traditional way of doing it, has proved to be very unhelpful. And an irony, and I've done it myself, mea culpa, is that the more clearly you explain what is at stake, the more likely you are to drive your audience into a state of anxiety, fear, guilt, and in particular helplessness. The human brain has ways of dealing with that discomfort which are very unhelpful. And I would say that a lot of the pushback that we've had from society about climate change has been because climate scientists, by and large, are not trained to understand how to manage an audience, how to manage the emotional reaction that they inevitably generate in an audience. So we have shut people down, people have gone into denial, people have gone into negation, people have gone into disavowal. All of the problems have militated against having what we were trying to do: to have an adult discussion about where we go from here. Because, you know, humanity didn't do this on purpose. I mean, look at the benefits we've had from burning fossil fuels. You know, the world is an amazing place, we can support a fraction of a very much larger number of people that would ever have been conceivable in the past. But the planet is disinterested, and simply responding to what we've done, so we need this adult conversation. So, what we're trying to do is to use Mind Science insights to tell a story, which is of action - finding your agency. We are not dealing with people who are still in negation and denial, we're dealing with people who want to do something, but are stuck. And there are a myriad of these, both at the individual level, particularly at the institutional level. So, individual institutions, communities of practice, communities of place, and what we're doing is we're trying to get inside people's heads to say, well, what's blocking you? Is it a personal, anxious, helplessness thing? We can help with that. Or is it an institutional blockage of some sort, like, for example, an oil company, an oil and gas company, that can't see the route to becoming an energy company without having to trash a whole load of its existing assets, both human and infrastructure, and without risking losing its investors, because the path is seen as too dangerous. So what is it that is blocking your ability to move forward? And how can we work with you, as honest brokers, to co-produce... It's a two-way discussion. Is science able to help you? It may not be able to, because it may be too difficult a question, or it may be the mundane application or front-ranking science, which nobody has ever funded yet. But let's hold that conversation and help you find your agency to act. And as we enter that process, by and large, we have no idea what will emerge, but what we find is that by applying these principles and insights we're getting a portfolio of countless - well, they can be counted, but it's hopefully going to be countless soon - examples where we have liberated people, they found their agency, and they found a way forward. And so it's multiplying that up, again, through communities of practice and communities of place, that will allow us to increase the scope and pace of action on climate change. So it's all to do with actions driving beliefs and not the other way around. Children of the Enlightenment believe that by offering people facts and information, that some magic will go on in people's heads, and they will leap forward and start doing the right thing. That is not the way it works. And we help people overcome those barriers to find their agency. And when they do, once they've made that first step, the self-justification engine in our heads goes, hey, I'm a smart person, I obviously didn't do something stupid there, it makes me feel good that I did something measurably useful. Now I'm on the route to doing more because come to think of it, we can do this additional stuff as well. So that's the final message, that actions drive beliefs, and getting people on that first rung of the ladder is a crucial step and it can be done.


Michael Liebreich Chris, you've done something extraordinary there, you've changed... So I kept on trying to sort of bait you into presenting the most apocalyptic view - the climate scientist says we're all in trouble, and it's going to be much worse than we think, and the floods, and the fires - and you've actually tap-danced around it, and then you've finished up with his rousing actions drives beliefs, and the work that you're doing at the Climate Action Unit, it's just extraordinary stuff. And of course, so many resonances: with Christiana Figueres, who was episode [6] of Cleaning Up; Dev Sanyal, Episode 99, who is leading a pretty substantial oil, midstream and downstream fuels company, towards net-zero on scopes, one, two, and three, because he has, his actions drive his beliefs and his beliefs drive his actions, and you can feel the acceleration when you listen to it. So you're plugging so many of my episodes. It's just fantastic. And we're out of time.


Professor Chris Rapley All right, well, it's been a real pleasure. And there's plenty more we could have discussed. But, I mean, I think in the end, we all have to have hope. People ask me, are you an optimist or a pessimist? And jokingly, I sort of say, well, on Mondays, Wednesdays and Fridays... I veer, I read the headlines, I read the latest papers, and I veer. But you know, in the end, the world will go on. I hate it when people say we've got to save the planet; the planet is indifferent and perfectly capable of looking after itself. And it will do; we've done a lot of damage, but give it time and it will recover, we know that. It's human wellbeing that we're talking about here. And you know, I've got children and grandchildren. You've got to believe that even though we're in a bit of a mess, we are not stupid. On a finite planet ingenuity, human ingenuity is unbounded, and there have been plenty of examples in the past where we have managed to rally together. We've left it very late, but there is a huge upsurge... I mean, if you talk to young people, they are worrying, you know, they do suffer from climate distress, but they are, they're the people who see the world differently. I had a conversation with some young people the other day and said, well, look, you know, there's hope. Ben van Beurden, head of an oil and gas company said, my next car will be electric, how about that? And they rolled their eyes and said, yes, but that presupposes that we want cars, Chris - we just want mobility. So, you know, think differently. And that's where it'll all come from.


Michael Liebreich Optimism and pessimism, I can't remember who it was.... It was either Winston Churchill, or Craig Venter, who sequenced the human genome, who said, I don't know whether I should be optimistic or pessimistic, but I do know it'll be the optimists who get something done. So that's kind of the motto for your institute there...


Professor Chris Rapley Absolutely. Beautiful phrase to end on.


Michael Liebreich Chris, thank you so much for joining us here on Cleaning Up.


Professor Chris Rapley My pleasure, really. And you and I will continue this conversation in the sidelines for a lot longer, won't we?


Michael Liebreich Very good. We certainly will. So that was Chris Rapley, Professor of Climate Science at University College, London's Department of Earth Science. My guest next week is Silvia Madeddu, and she is an expert on the decarbonisation of industry, particularly the application of green heat. Please join me at this time next week for a conversation with Silvia Madeddu. Cleaning Up is brought to you by Capricorn Investment Group, the Liebreich Foundation and the Gilardini Foundation.