Source: BBC Radio Five Live
URL: http://www.bbc.co.uk/podcasts/series/drkarl
Date: 19/05/2011
Event: Naomi Oreskes is a guest on Radio 5 Live
People:
Rhod Sharp: I'm very pleased to see that Dr Karl is with us in Sydney, in the studios of the ABC. And this week, Dr Karl, we have a guest - perhaps you would like to introduce her.
Karl Kruszelnicki: Ah yes, now this is a person who was born in the top right-hand corner of the USA, home of 90% of the irony that the USA possesses. Then in [inaudible] degree, then going to London. And then in London, was asked to become a geologist in Australia, which seems rather a perverse sort of thing. And then decided to get married in Australia. And then, well, in the outback and travelled all the way to Darwin to get married in Australia. And then wrote the paper, back in 2004, that really said that if you look at all the scientific papers dealing with global warming, written in peer-reviewed journals, the number of them that disagree with the concept of global warming is zero. There is no debate in the scientific community. And this is in 2004. Of course I'm talking about Naomi Oreskes, the author of a wonderful book which she then wrote called Merchants of Doubt. And she creates a link between an organisation called the George C Marshall Institute, so she's shifted from geology into the land of scientific, historical writing, as well as having a scientific background, because she is, in fact, has [sic] a PhD in this field. And shows there's a link between, er, the George C Marshall Institute and all the denial that they've pushed, and, for example, they claim there's no link between tobacco and lung disease, there's no link between CFCs and a hole in the ozone layer - just by the volcanic warming, they claim - volcanic eruptions - there's no link between coal-burning sulphur and acid rain - once again, blamed on volcanoes, and there's no link between humans dumping carbon dioxide into the atmosphere and, um, global warming. And so, this person is Professor Naomi Oreskes, author of the book Merchants of Doubt, which I've read, and, um, which I lent to my neighbour. who then went and bought a copy and now he's reading it to all his workmates at the factory. So I'd like to introduce to the microphone Professor Naomi.
Naomi Oreskes [very faint]: Hello, nice to be here with you.
Rhod Sharp: Good... [inaudible] the other microphone.
Karl Kruszelnicki: I forgot to switch the microphone on.
Rhod Sharp: And again.
Naomi Oreskes: Oh!
Karl Kruszelnicki: My fault!
Naomi Oreskes: Oh gosh! Hello, it's great to be here, Dr Karl...
Rhod Sharp: How nice to meet you. How very nice to have you with us. So we can talk to endlessly, can we, about climate change and global warming?
Naomi Oreskes: As long as you like.
Rhod Sharp: Oh, fine. Well, that's fine, that should keep us busy. Um, so there you are, if you have questions, indeed if you are a convinced doubter [sic] of the human effect in climate change, now is your chance to have a go. And we'll see what Naomi has to say. I wanted, just before we get into our calls, if - 5058 for your texts, by the way, upallnight@bbc.co.uk for your e-mails, and 045 909 693, our operators are standing by, as they always faithfully do. I've got something for you, Dr Karl, because this is a long, but I think quite excellent explanation of why you couldn't have identical twins, or why it would be extremely difficult for two sets of identical twins, who then married opposite numbers, to actually produce any more identical twins. Do you remember, we were asked that.
Karl Kruszelnicki: Hmm, mm.
Rhod Sharp: So here we go. This is from Alan Day in Oxford and he says, he says: what if you were to have genetically identical men married to two genetically identical women, what's the chance of a child from the first couple being genetically identical to the child from the second couple. That was the theoretical question. Um, and he says it's no different from asking what's the chance of a single couple having lots of children in their lifetime and producing two genetically identical children from different births, i.e., not birth twins. Er, and he asks: how many people look absolutely identical to their older or younger brother? No-one at all. So we know it's very unlikely, but why? The reasons - now here, this is his reasoning - each chromosome in our DNA consists of two strands of genes and the two strands are not identical. Each sperm and each egg contains one strand of each chromosome, but it's a 50-50 chance which the two strands it will contain. Because we have forty-something chromosomes in the human cell, there are two to the fortieth power ways of picking a set of chromosomes strands, which is something like several trillion, I think. So if the chances of one man, or two identical twins, producing two identical sperm is one in a trillion, and likewise for a woman producing eggs, so the chances of getting two identical offspring is one in a trillion trillion, which is the answer to the question I think your caller was asking."
Karl Kruszelnicki: Hmm. Because the beauty of sex, and um Richard Feynman the Nobel Prize winner said that science is like sex - it might have practical results but that's not why we do it - the beauty of sex is that you jumble up the DNA to give a different baby each time. And this baby might be shorter, taller, darker skinned, lighter skinned, better swimmer, worse swimmer, whatever the environment changes to, hopefully one of the children will be able to survive. And that's the advantage of sex over where the other form of reproduction where the - you just have the splitting-off of, for example, bamboo and bananas, and where the offspring are genetically identical to the parents. If the environment changes, they're in trouble, they can't shift. That's lovely, so two to the fortieth, I worked out, is two to the tenth, raised to the fourth, and two to the tenth is ten cubed, raise that to the fourth, that's ten to the twelfth, that's a trillion, a very big number. Certainly more than the population of Earth.
Rhod Sharp: Oh yes, I'll say. Right, Ollie has sent us in a question, on a text terminal [?], and he says - and I think this is to the point, and, er, maybe Naomi can take this one. Um, and he says "Does less water in the ice caps mean more precipitation?" Er - "so why are we having more floods", says Ollie, "in wet [?] countries like Britain?"
Naomi Oreskes: Great question. Right, well that's a great question, and the answer is yes, although not exactly the way he put it. So more melting of the ice caps leads to more water pouring into the oceans, and rising of sea level, with the potential to affect coastal erosion, drown major cities like Sydney, where I am right now, er, damage infrastructure, historic monuments new sea level [?] And so that's one of the most important concerns about climate change, that sea level is already rising, it's happening now, and it will impact millions, or hundreds of millions, of people around the globe. Er, in addition, though, as the atmosphere gets warmer, it's able to carry more moisture. Warm air can hold more moisture than cold air. So as the globe, as a whole, warms up, the atmospheric system there's more evaporation, the atmospheric system can hold more moisture and therefore we expect to see heavier rains and even flooding in some parts of the globe. And indeed scientists are saying that we are, in fact, seeing evidence of that, the floods in Pakistan last summer, floods in Britain, and of course the terrible floods that are affecting my home country right now, with the US Corps of Army Engineers is having to deliberately inundate millions of acres of highly productive farmland in order to save certain historic American cities.
Karl Kruszelnicki: So -
Rhod Sharp: Spoken like a farmer, I may say.
Naomi Oreskes: Well, I'm not a farmer, I grew up in Manhattan -
Rhod Sharp: Oh well -
Naomi Oreskes: - but I have sympathy, great sympathy for farmers, and of course we all depend upon the food that they produce.
Rhod Sharp: Indeed we do. Indeed we do. Anything to add to that, Dr Karl?
Karl Kruszelnicki: Yeah, they were finding in the Antarctic that there was a mixed bag, that ice was vanishing in some parts and reappearing in other parts, and was related to the fact that the water was warmer, therefore more water molecules were evaporating off to form more clouds, which could fall as snow. So you do get local turbulent effects, er, in some parts of the world overall, will get, er, drier, some will get wetter. Australia, unfortunately, looks as though it's going to become even more relentlessly dry as the effects of global warming roll on down the decades.
Naomi Oreskes: Yeah, and if I can just add to that, since we were talking earlier about doubt-mongering, this is really important for people to understand, because, of course, sometimes people who are sceptical or in denial about climate change would like to say "Well, it snowed in Washington DC, how could there possibly be global warming, ha ha ha?" But of course, this is exactly how there can be snow in Washington, and the climate models predict this, and everything we're seeing now is consistent with what we know of the laws of physics.
Karl Kruszelnicki: So, for example, in Europe, and I'm heading there this winter, to visit relatives, see the Large Hadron Collider and sit in a hot pool in Iceland and see the aurora borealis, um, what happened in the last winter was that it was unseasonably cold. And if you look at the bigger picture, Europe is a small area, Europe, America, the further north you have a big area where it was unseasonably warm. And it was a bit like opening the fridge door and letting all the cold air flood out. That would be the rough metaphor. Overall, the world was warming, and there was the northern areas warming a lot, and some insignificant areas like the USA and Europe cooling down a bit. Yeah, but overall, on average on surface area, not population but surface area, more land warmed up than cooled down.
Rhod Sharp: So I think that answers the question that Lee from Sussex has just texted, because he said about four years ago a really hot long summer and at the time, experts were coming on the radio and saying we'll have to get used to these kinds of summers because of climate change, but since then our summers have not been good at all. That's exactly what you're saying, isn't it, that doesn't necessarily follow.
Naomi Oreskes: Exactly, and I mean, sometimes people ask me "Should we call it global warming? Should we call it climate change? And the answer is that it's both. The world as a whole, as Dr Karl just said, is warming up, the average global temperature is about point eight of a degree Celsius higher than it was 150 years ago. But, in terms of the climate system, there's a lot of variability. There we're looking at climate change, some places will get hotter but some other places may get cooler. London may get cooler. Er, some places will get drier, some places will get wetter. We'll see shifts in the patterns, and, of course, this matters a lot, because any change challenges people. If humans, as a species, are not very good with dealing with change, and especially we're not very good at dealing with change that happens suddenly. So the more we begin to see changes, unanticipated changes, things we're not used to, the more we'll see dislocations associated with climate change.
Rhod Sharp: Yeah. Let me go back to something that Dr Karl was talking about. We were dealing with, really a couple of weeks ago now, do you remember about the rear view mirror, Dr Karl?
Karl Kruszelnicki: Yes.
Rhod Sharp: Aha. Well, I have a question, I mean this is Nick in Barnsley, and I think he is going to, he's going to ask you something about that. So let's just bring him up.
Karl Kruszelnicki: Dr [?] Nick, welcome to the show.
Nick: Hello. I just wondered if you've done the - you said you were going to go away and do some research. You wrote it on your hand, and er, have you done that? And what was the outcome, really?
Karl Kruszelnicki: Ah, I did the research, which meant basically going down to the car and opening the door, and then sitting inside and then remembering to look in the mirror and then taking my glasses off. With my glasses off, with flat mirrors, both on the inside of the car, the flat mirror on the inside of the car, um, I can't see far distances without my glasses and focusing on the mirror, the image in the mirror was blurry. I could see the mirror frame perfectly clearly but the image was blurred. Then I looked at the external mirror which is dished outwards, which is a convex mirror, and once again, the same pattern. The frame of the mirror was perfectly in focus, because I could see really well at close range, but the image in the mirror was way out of focus. Then I went inside to have a look in a convex - no, concave mirror, that was a convex mirror, now I'm looking in a concave mirror, which is dished inwards, and then... life took over and I forgot what I was doing. Er, so I haven't done the last part of the experiment which is simply to look into a convex mirror like a deeply dished mirror, because the saying was that if you look in such a mirror, you will see the outside world perfectly sharp if you focus on the mirror. And I haven't done that experiment. We were dealing with [?] someone who needs their glasses to see far away, they said they were looking into a mirror without their glasses, they could suddenly see everything in focus. But the thing is, with a deeply dished mirror, concave mirror, the world is upside down. No car has a mirror where you see the world upside down. But I haven't got to that part of the experiment, because life got in the way. I'm sorry, I'm a very bad experimenter.
Naomi Oreskes: No, you're a normal scientist, this is what happens in science all the time.
Karl Kruszelnicki: Yeah, life gets in the way.
Rhod Sharp: Can I, er, can I add something from Gwynne Evans, who by the way, he knows how much you think of Alastair Reynolds, and he says "I used to work with Alastair's father in South Wales." So, remember Alastair Reynolds?
Naomi Oreskes: Ah.
Karl Kruszelnicki: Alastair Reynolds is a science - he used to be an astrophysicist and left it to become a science writer and, um, writes his wonderful science fiction space operas. Where they cover families that run over tens and hundreds of years, and thousands of years, and sometimes millions of years - in this time dilation, you cross the galaxy and you're limited to the speed of lig and some people who live in hives like the Borg, and all sorts of stuff, and it's really fascinating.
Rhod Sharp: Right. Here is Gwynne's thought about mirrors. He says "When I was in the physics lab in school, almost fifty years ago" - he didn't need to add that, Gwynne, it's okay - "we did the experiment to locate the image in a mirror. We used pins, and I remember squinting across the surface of the bench, lining up the image of the pin with its perceived location. We found out that it was - quote - as far behind the mirror as the object was in front. That would suggest that viewing a scene in a mirror with reading glasses shouldn't have any effect on the clarity of the image. I must admit, I haven't tried it, myself. Just like you, Dr Karl, " says Gwynne, "I keep forgetting."
Karl Kruszelnicki: I keep forgetting. Like, I think had to empty the dishwasher or load it or something -
Rhod Sharp: But is that not a good yardstick, that the image is as far behind the mirror as the object is in front.
Karl Kruszelnicki: This was a flat mirror. But we've got to do the dished mirror one. Now -
Rhod Sharp: Aye, aye...
Karl Kruszelnicki: - to see where the images are -
Rhod Sharp: Okay. Naomi, our texters are holding your feet to the fire about historic climate change -
Karl Kruszelnicki: Feet to the fire -
Naomi Oreskes: Yeah, I like that metaphor, it's good -
Rhod Sharp: I know we don't have many fires -
Naomi Oreskes: I hope I won't be burned at the stake.
Rhod Sharp: No, you'll be fine, you'll be fine. David in Bristol says "I'm pretty sure it was hotter in the Middle Ages than it was today - "
Naomi Oreskes: Ah -
Rhod Sharp: "Surely", says David, "the Earth naturally goes through hot and cold periods. Leading on from this, we don't yet know enough about the way the Earth works, e.g., dust particles, to determine the possibility of global warming."
Naomi Oreskes: Ah, well that's a great question. So, there's several things there. David is referring to what scientists call the Medieval Warm Period. The Medieval Warm Period is very well documented, we know a lot about it from historic records, we know a lot about it from tree-ring studies, ice cores, coral reefs, etc. And we know two important things about it. One is that the Medieval Warm Period was a phenomenon in Europe. It was warm in Europe, it was not warm everywhere else on the globe. Coral reefs from tropical areas do not show evidence of warming, so it was not a global warming phenomenon -
Karl Kruszelnicki: Just a local thing.
Naomi Oreskes: It was a regional phenomenon.
Karl Kruszelnicki: You could fit all of Europe into Queensland -
Naomi Oreskes: Well, exactly!
Karl Kruszelnicki: - and have room left over, Europe's tiny, compared to -
Naomi Oreskes: I don't want to insult our European friends, but the important thing is to realise that does not refute global warming. Second of all, er, crucial work done by scientists, including the much-maligned but wonderful people at the Climate Research Unit in East Anglia, have analysed historic temperature records and show that even given the Medieval Warm Period, the warming we are observing today now is greater than the warming that took place in Europe during the Medieval War Period. So yes, absolutely, there is natural variability, life is interesting, the world is interesting, climate change is, but the changes that we are seeing now are different, they are bigger than the known changes in the historic records. And moreover, and this is the important thing, it's most important for people to understand, it's not just random variability. We know something about the laws of physics and chemistry, and one of the things we know is that if you put more greenhouse gases into the atmosphere, the atmosphere traps more heat. This was first discovered by the great Irish experimentalist John Tyndall in the 1850s, and the prediction that climate change would happen from increasing greenhouse gases was first made by Svante Arrhenius at the turn of the century - the great Swedish geochemist Arrhenius was Swedish, so he thought global warming would be a good thing - er, so this is a basic prediction from the laws of physics and chemistry. And what we are seeing now is that those predictions are coming true. So yes, there is natural variability, but on top of that natural variability there is a trend, and that trend is being driven by greenhouse gases, and also deforestation.
Karl Kruszelnicki: What about the dust particles?
Naomi Oreskes: Thank you, actually I have a little note that someone was going to say something about that. We actually know a lot about dust particles too, and again from historic records, so lots of people have heard of Krakatoa, Tambora, the great John Turner watercolours, the beautiful sunsets. Those were the consequence of dust particles in the atmosphere after volcanic eruptions. We know quite a bit about cooling effects of dust particles, and one of the really brilliant pieces of scientific work that was done in the last twenty years was by Jim Hansen, the NASA climate modeller. So people often say "Oh, you can't prove global warming, you can't test it, the models are uncertain, they're just models, why should I believe a model?" Well, people are right to be sceptical of models, I'm sceptical of models, I've written some articles about this. But Jim Hansen did something incredibly brilliant after the Mount Pinatubo eruption in the Philippines. He realised that the Earth would probably cool as a result of the dust particles in the atmosphere. And so he did a very courageous thing. He took his global climate model, a general circulation model of the atmosphere, which was designed to model long-term warming from greenhouse gases. It was not designed to model volcanic eruptions, but he said" If this model is right, and if we've got the physics and the chemistry right, we ought to be able to predict the temporary cooling effect from Pinatubo, in addition to predicting the long-term warming effect. And so he took the data that volcanologists gave him about the amount of dust that had been put into the atmosphere from Mount Pinatubo and he used the model to forecast what the cooling, the temporary cooling effect of that dust should be, until the dust particles settled out. And he got that prediction right. And to me, that was very courageous, because he put his neck on the line, um, and it showed that these models do appear to be reliable, and it would seem that as far as we can tell, they do seem to have the physics and chemistry right.
Rhod Sharp: Mm, wow. Let's, er, let's have another putative cause for everything we're going through, as we're joined by Andrew on the phone, Andrew from London. Hello Andrew.
Andrew: Good morning, good morning Rhod, good morning Dr Karl and good morning your guest.
Naomi Oreskes: Good morning.
Andrew: Following on from what you've just been talking about - oh, by the way, Dr Karl, before I ask my question, something of interest to you. On, er, we have a phone-in programme run by Dotnet Dubai [?], where people choose books to go to a virtual bookshop, and I phoned in and recommended one of your books, Munching Maggots, Noah's Flood and TV Heart Attacks, which I've got. Got lots of votes, but didn't quite get on, Dr Karl, but anyhow, I -
Karl Kruszelnicki: It's got a picture of me, nude in a mudbath with my son on the back cover -
Andrew: That's you -
Karl Kruszelnicki: - in California.
Andrew: Yeah, yeah -
Karl Kruszelnicki: What do I have to do, that was my eighteenth book. I mean -
Andrew: Well, I recommend it, it's a fascinating book, full of great, you know, great, sort of, bits of information and so on. And you got lots of votes, but just didn't get on with our virtual bookshop, but just thought I'd let you know about that.
Karl Kruszelnicki: Ahh... Thank you.
Andrew: Now, talking about our - the global warming, the accepted theory is that, you know, carbon dioxide and other gases produced by us horrible human beings, cars, planes, coal-powered power stations and so on. But I've read an article by three Danish scientists who say that most of the global warming is caused by the interaction of cosmic rays coming from [inaudible] stars and the Sun. When the Sun is in this mood, it causes more warmth, when it's not, when it's quiet, there's less warmth. And they claim that most of the changes in climate, most of them, are caused by the Sun and cosmic rays rather than man-made. What do you say to that?
Naomi Oreskes: Yeah, thanks, that's a great question, and it's great when we get these things out in the open, so we can discuss them -
Andrew: Sure. Sure.
Naomi Oreskes: So, um, I think this is a really good example of the length that people will go to deny the fact that we have a responsibility here, and that we have in fact changed the atmosphere. So my co-author on Merchants of Doubt is Erik M Conway, he works for NASA, and one of the things that NASA does is that it measures solar radiation. NASA has had highly accurate satellites up in the atmosphere since the 1970s, measuring solar irradiation, and we know from that data that there has been no general increase in solar irradiance over the period of time, during which we've seen -
Karl Kruszelnicki: Now I should just point out that we - the Sun is not a constant candle -
Naomi Oreskes: No. Right -
Karl Kruszelnicki: - and it varies by roughly one tenth of one percent over an eleven year cycle.
Naomi Oreskes: Right. So we know, like the climate system itself, we know there's natural variability in solar irradiance, but what we're talking about is a trend -
Karl Kruszelnicki: Ahhh.
Naomi Oreskes: We're trying to explain this trend of the suddenly increasing warming that we've observed over the last fifty or sixty years. And that trend, there is no increase in solar irradiance that would explain that observed trend. And in fact, in the last ten to fifteen years, solar irradiance has actually gone down a little bit, even while we've seen warming continuing. The warming would probably, actually be greater, were the Sun not in a slight declining period right now. Now I want to say just one other thing about what you just said, Andrew. So you, you use the phrase "us horrible human beings" -
Andrew: Yes.
Naomi Oreskes: I'm glad you said that, because I think this is really the crux of the denial issue -
Karl Kruszelnicki: Ah-haa...
Naomi Oreskes: - because global warming makes people feel bad, because they feel that they're being told that they're bad people, that we're horrible, that we're doing all these terrible things. But of course, I spend most of my time with climate scientists, and climate scientists almost never talk about "horrible human beings", unless it's their department chair, or their dean or the president of their university. You know, for scientists, this isn't about whether human beings are good or bad, it's about the laws of physics and chemistry. It's about the chemistry of the atmosphere and what's happening to our climate system. Yes, it does mean that there are consequences that we need to talk about, but personally I feel that human beings are, by and large, great. I love Dr Karl here, who's sitting in the room with me. Er, so it's not about people being horrible, it's about people having lived a lifestyle that made us prosperous, made us wealthy, made us happy - it's been good, by and large, we've had a good run - but now we've discovered that there's this little problem, and we need to do something about it.
Karl Kruszelnicki: Now one other thing, Andrew, you mentioned the paper by the three Danish scientists and the cosmic rays -
Andrew: Yeah, yes, I can give you their names, if you like.
Karl Kruszelnicki: Can you give me the date of the paper?
Andrew: No. No - I remember reading it, I took their names - Knud Lassen -
Karl Kruszelnicki: The point is -
Andrew: Eigil Friis-Christensen and Henrik Svensmark -
Rhod Sharp: Henrik Svensmark. And Henrik Svensmark co-wrote a book with Nigel Calder, who's a British science writer, which we talked about with Nigel on this programme, called The Chilling Stars.
Andrew: Hmm,mm.
Rhod Sharp: And that book is, that book is very much still out there.
Andrew: Ah.
Naomi Oreskes: And you know, what's interesting, also, about cosmic rays, people love to blame cosmic rays for lots of things, just like they love to blame volcanoes, and in our book we show how practically every major environmental problem there's been in the last fifty years, someone has tried to blame volcanoes. And, you know, volcanoes are like the scapegoat of the planet, because we know they exist and we know they do put dust and sulphur and -
Karl Kruszelnicki: They cool down the planet, like the Pinatubo event -
Naomi Oreskes: They can -right, but - but the Pinatubo event cooling lasted about two years, it was a very short-term event, and although it's - volcanoes do a lot of damage, they don't explain global warming, they don't explain acid rain, there's just a lot of things they don't explain -
Andrew: So could I just say to sum up - do you say that cosmic rays, in conjunction with the Sun's vigorous, sort of, moods, play very little part in global warming?
Karl Kruszelnicki: Well, the point I was getting to was that the paper was written about a decade ago -
Andrew: Ah.
Karl Kruszelnicki: - and the scientists - other scientists - have gone through it, and basically said "Interesting idea, but completely wrong." So it's been thoroughly debunked -
Andrew: Yep -
Karl Kruszelnicki: - in the peer-reviewed literature, since then.
Andrew: Well, I bow to your greater knowledge.
Karl Kruszelnicki: And with regard to the East Anglia people, the Climategate thing, the worst thing, after a very intensive investigation, the worst thing they could find was that - and I quote - not all scientists like each other. Well hey, not all plumbers get on automatically with all other plumbers, not all carpenters like all other carpenters, the worst thing is they say "Oh that Naomi, God, she pushed in the queue in front of me in the cafeteria, God I hate her", that's about as big as it gets. That was the most damaging finding they could come up with, was that not all scientists like each other.
Naomi Oreskes: And they're not always nice to each other, either -
Karl Kruszelnicki: And they're not always nice to each other. But the science is robust.
Rhod Sharp: Well, welcome back to a special Dr Karl, who today has as his guest Naomi Oreskes, who has done a great deal of work on what she has called "denialist claims", and I want to start of with a little story for you both, because recently I was lucky enough to go to the Royal Court Theatre, and I saw a play by Richard Bean called The Heretic. And I don't know if any word of that actually reached you in Sydney or wherever you actually were at that point, Naomi, this was about six weeks ago, or something. Anyway, it's basically a story about climate change deniers, and a woman called Dr Diane Castles teaches palaeo-geographics in a modern British university, and, er, the kind of climactic scene of, of the kind of laying out the theory, involves Jeremy Paxman, who is hosting her on Newsnight, and she is busy telling him, um, that, for example, "I've been measuring Maldives sea levels", she says, "for nearly twenty years. It's not rising." Er, the President of the Maldives can tell his people to relax and enjoy their island paradise. And Richard Bean talked to a lot of climate scientists, we understand, and he says that basically - she says - without going - reading the whole scene - er, is that in fact, it's not the sea water that's rising, but the land that's rising, or if the sea water's rising, the land is rising too, that seemed to be the nub of the argument, that the audience at the Royal Court very much enjoyed -
Karl Kruszelnicki: Ahh -
Naomi Oreskes: But wouldn't the land have to be sinking, if it's not the sea level rising? Sounds like she's got that backwards. Let me ask you a question - this is a work of fiction?
Rhod Sharp: Oh, it's total fiction. Yes -
Naomi Oreskes: Right, exactly. Well, that's the point.
Rhod Sharp: But it was fiction with - ha, ha - with the assistance of a lot of climate scientists -
Naomi Oreskes: Yeah, but this is the whole point. I mean, this is a work of fiction, just as Michael Crichton's book State of Fear was a work of fiction.
Rhod Sharp: Yes, of course.
Naomi Oreskes: And one of the things that some people like to do is to invoke these works of fiction as if somehow they were a counter-argument to the facts. And of course they're not. And you know, it's interesting - you said, you said I had worked on denialist claims, but actually I don't use that language, I don't use that terminology, we don't use that in our book, because -
Rhod Sharp: Ah, right, well, Dr Karl had better get that off his blog then, because I took it from him.
Naomi Oreskes: No, no, well that's all right but the point is it's a bit inflammatory, and the point we're trying to make is, we're not trying to say people are horrible people, we're not trying to say they're Holocaust deniers. We - in the book we call it doubt-mongering, and we point out that it was a strategy invented by the tobacco industry, and it's been used over and over again. And the strategy is simply to raise doubts. Because if I say "Well, you know, we don't really know if the sea is rising or the land is sinking", then a lot of reasonable people will say "Oh, if we're not really sure, then it makes sense to do more research, and it certainly makes sense to hear both sides of the issue." Um, so this is a very effective strategy but it's wrong, it's incorrect, it's not consistent with the scientific evidence. The overwhelming scientific data shows that the seas are rising, this has been measured across the globe, it's one of the most secure pieces of scientific data because as you know, being in the United Kingdom, er, scientists have been measuring sea level since the 18th century - some of the earliest records are from the United Kingdom - we know a lot about sea level. It's been measured systematically by many thousands of scientists around the globe. And the idea that all of these scientists are all wrong, and one fictional character in a play in the West End is right, that strains credulity.
Karl Kruszelnicki: But there would be somewhere in the world -
Rhod Sharp: No, no, I mean that - the point about this play, if I may just say, I mean I've obviously given a poor account of it, but just reading the back cover, um - Richard Bean says "Could the belief in Anthropogenic Global Warming be the most attractive religion of the 21st century?" So that - we're off into social science.
Naomi Oreskes: Ah yeah. Well, you know, that's interesting -
Rhod Sharp: "What else do we need", he says, "before deciding on policy?" So that, I think, was maybe his thing, was: have we got enough evidence? Are we going the right way?
Karl Kruszelnicki: Okay, um, the essence of religion, which, um, is a perfectly valid form of thought - and in fact in our school of physics, one of our top relativists, dealing with Einstein's Theory of Relativity, is also a Minister of Religion - um, religion is a perfectly valid form of thought which has zero dependence on proof and 100% dependence on faith. And that's perfectly valid. And in whatever framework it is - like, you would not use it, for example, if you're trying to work out how to - work out heart surgery, or something like that.
Naomi Oreskes: Fix your car.
Karl Kruszelnicki: Or fix your car. But - and then there's the other thing called science, which depends 100% on proof and zero on faith. And then to say "But surely they're the same thing" - no, they're perfectly different. Er, climate change does not depend on a whole bunch of people believing it, it depends on the proof. Er, a famous saying in science runs along the lines of: if 100% of people believe something, it doesn't make it true.
Rhod Sharp: But what we do, what we do about climate change does depend on our belief, because we don't believe -
Naomi Oreskes: Well, exactly. And that's the point, the point is that we need to have a clear distinction between the scientific evidence that tells us what's happening, and the policy or political discussion about what we should do about it. I find it incredibly interesting that the sceptics and contrarians like to accuse scientists of being religious about this, when, you know, every scientist I know spends huge amounts of time poring over data, trying to understand the data. And I was on the television here in Sydney, er, two days ago with a climate sceptic who called himself "agnostic", and I thought: the people who are invoking religious language are not the scientists, it's the people who are rejecting the science. As far as what evidence do we need, I actually think that is exactly the right question, and in my own, er, on my own website where I talk about my own work, I talk about how my own work has always been focused on the question: how do scientists know when we - how do scientists decide when we have enough information and data and evidence to say that we know something? And this is really the crux of the question of history of science. And it's part of what makes my discipline so interesting. So the answer is there's no magic bullet. There isn't an algorithm that tells us: now we have 17.5 to ten to the - you know, times ten to the fifteenth pieces of data, and therefore we know when we can move forward. It's not like that. Scientists are experts, they're human beings, they make judgements. And all of the scientific community, all the experts that have worked with us have told us that this is happening, and we're seeing the signs of it all around us. Melting arctic ice, shifting weather patterns, er, historic, record-breaking floods, hurricanes, tornadoes in Alabama, for goodness sake. So the question is: what do we do about it? And the longer we delay, the harder this problem gets to solve. And getting back to those dust particles, when a volcano erupts and dust particles go into the atmosphere, they typically stay there for a year or two, and then things - they settle back to earth, then things settle back to normal. When carbon dioxide goes into the atmosphere, it stays there for a century or more, so the longer we wait, the harder this problem gets to solve. And it's going to be with us for a long time.
Rhod Sharp: Naomi, let's take another question. And this comes from Mike, who's calling us from Barr in Ayreshire. Hello, Mike.
Mike: Er, hi there. Um, good evening doctors, Karl and Naomi.
Naomi Oreskes: Good evening.
Mike: Um, is Britain going to get hot or cold? The reason I ask, is that I was watching a programme, um, which told me that yes, greenhouse gases are making the world warmer, but as a result of the world getting warmer, um, we have the Arctic Ocean, and I assume the same's going to be - it'll be the same down in the Antarctic, um that the ice from the Arctic will melt and flow into, um, let's say the Atlantic. Um, which then will affect the Gulf Stream. And because the Gulf Stream gets screwed up, then it's going to affect temperatures and we're going to have a massive ice age. Instead of the actual world warming up, we're then going to experience some sort of ice age, because the Gulf Steam has become interrupted with fresh water.
Naomi Oreskes: Yeah, well so this is one of the legitimate and real uncertainties in climate science. There's a lot of nonsense out there about uncertainties, but there are legitimate and real uncertainties. So when we look to the future and we try to know what will happen in the future - of course, as Niels Bohr famously said, or is said to have said, that it's very difficult to predict - prediction's very difficult, especially about the future - so, one of the concerns of climate scientists is exactly what you just described, that melting of Arctic ice puts fresh water into the North Atlantic, and this has the potential to alter the circulation of the North Atlantic, which has the potential to shift the Gulf Stream. And as most people living in Britain know, the Gulf Stream is crucial for you guys because without the Gulf Stream you would have a climate much more like Labrador.
Mike: Uh-huh.
Naomi Oreskes: So there is the potential for the United Kingdom to get colder. An ice age - no, probably not, not in our lifetimes. But a shift in the climate that could cause chillier weather overall, yes that is considered a possibility by many experts.
Karl Kruszelnicki: And when you say "ice age", traditionally an ice age is related to the Milankovitch Effect, traditionally lasts for forty or a hundred thousand years, depending on which part of the cycle it is, and during the ice age, the ice is one kilometre thick over New York and Germany, ocean levels drop by 100 metres. So "ice age" is not the correct term. Er, I'm looking at it from two points of view. One is: England is such a microscopically small - the United Kingdom is so microscopically small in the world [Mike is laughing] you could drop it into New South Wales and you wouldn't even know it was there. And so to try and work out what was happening in one small area is - of the world is very difficult. On the other hand, we do know of the thermohaline current, which keeps that part of the world warm, and we do have very strong evidence that fresh cold water coming from the North Pole into the Atlantic can - has in the past, we think, switched off the thermohaline current, and were it to do it now, England would be a good replica of Labrador.
Mike: So, would - could the same happen in the Antarctic? Would we get more El Ninos, or would that it affect the El Nino -
Karl Kruszelnicki: Different again, because in the Antarctic, you do not have a similar oceanography. The Arctic is an ocean, er is an ice mass, surrounded by land. The Antarctic is this huge sea - we've got the Antarctic ice mass, and then you've got this huge area of sea and it's not surrounded by land. You have three skinny points of land pointing into it - there's North America - sorry, South America - there's Africa and there's the - bit of Australia. And then going around it, you have these huge, what's called a circumpolar current, so the currents are completely different from one Pole to the other. Massive land-masses in the north, massive ocean in the south, quite different local - like politics, day-to-day weather is local.
Naomi Oreskes: Yeah, and it's really important, because the local variability is one of the big challenges of understanding how to respond to climate change. Because some parts of the earth will get warmer, some will get colder, some will get hotter, some will get drier. So if we begin to talk seriously about what we need to do to prepare and adapt to climate change, then we realise we have a huge challenge. Because it won't be the same everywhere, it will be different in different places, and in many cases it will be very hard to predict what will happen in any one particular area. So if your town council want to know what's going to happen in your town -
Mike: No, but I know -
Naomi Oreskes: - we can't, we can't make that prediction.
Mike: But how much then of this kind of science is guesswork and how much is actually known?
Naomi Oreskes: Ah well, again, I always like to say we know a lot more about the past than the future. So we know the climate has warmed up, we know carbon dioxide has increased by about 33% since the Industrial Revolution, we know that carbon dioxide in the atmosphere has come primarily from burning greenhou - burning fossil fuels, er, and we know that there're changes under way, but when we start to talk about what will happen in the future, how quickly it will happen, how those results will be distributed in time and space, then we get into a much more difficult territory.
Karl Kruszelnicki: We know the ocean levels have risen by 10 centimetres around the world, and as Rhod was alluding to, if at the same time as you have a rise in ocean level - it was 10, no it's 20 centimetres - if you have a rise in ocean level, and at the same time your local island is rising, then as far as you're concerned, the ocean hasn't risen at all, but overall, over the world, in the overwhelming majority of places where we have the measurements to measure the heights [sic] of the ocean, it has risen. We've looked at 20 centimetres in the last century -
Mike: On -
Karl Kruszelnicki: - er, at the moment we're looking at about 1.6 metres by the end of this century, but that's without all the feedback loops. Once you add in the feedback loops, you're getting bigger numbers.
Mike: On, on that point of sea levels rising, with, um, induction zones and, what is it, subduction, with the amount of earthquakes and things that we've had, and with the sea level - sorry, not the sea level - the, um, abyssal plains, etc., rising with a result of earthquakes and volcanoes, is it not that that's possible that's raising the sea level?
Naomi Oreskes: No, I mean, yeah these are two quite different things. My earlier work was on plate tectonics, so I know a fair amount about both these subjects. Er, earthquakes and tsunamis are not related to climate change. They've always happened, they always will happen. They obviously can do great damage, as we've just seen in Japan this last month. Er, the abyssal plains are not rising, the abyssal plains are doing the same thing they've been doing for hundreds of millions of years -
Mike: But if you have, if you have earthquakes, etc., and with each earthquake you have a certain amount of land rising, and, er, or cracking.
Karl Kruszelnicki: Hmm?
Mike: Surely, um, if you displace land underwater, that is squeezing the sea area, to actually raise it as well.
Karl Kruszelnicki: Oh okay, what you're saying is that - okay, the Earth actually has the wrong name, it should be called planet Water, because 70% of it is covered by water - so you're saying that if there were this circumstance, that the 70% of the surface that is underwater were to rise, and the 30% that's above water were to fall, that would mimic rising of the oceans. True?
Mike: Yeah.
Karl Kruszelnicki: It would. But it's not happening.
Naomi Oreskes: There's no evidence that that's taking place, right.
Karl Kruszelnicki: We've got satellites now that - pairs of satellites, the GRACE satellites, and we can measure down to - millimetres?
Naomi Oreskes: Yeah, yeah.
Karl Kruszelnicki: We've got very very tight measurements around the world. There's absolutely zero evidence for that scenario.
Mike: Right, right.
Rhod Sharp: Mike -
Mike: Um, just - I don't want to take up your time, just one final point -
Rhod Sharp: We're kind of stuck for time, Mike, so I'm going to pass on, but thank you so very much for all your points. Because everyone wants to talk about this. Um, we have an e-mail here from Tom. And he says "The sea started rising at the end of the last ice age. Is the current situation simply a continuation of that natural process? Sadly there were no man-made reasons for that to happen, ten thousand years ago. And this was not the first such melting of that ice."
Naomi Oreskes: Yeah, well again, this is a good example of how there can be more than one cause of something in the world. So there are many things that can cause sea level to rise, but we know from the measurements that actually sea level did rise at the end of the last ice age, it started to level out, and now we're seeing the sea level rise accelerating again. So again the trend has been changed by human activities.
Rhod Sharp: And how do you see Professor James Lovelock's view that it's too late to try to save the planet, this is the BBC news site in March last year. And this is of course the father of Gaia theory. He now says we should be putting all our efforts into mitigation.
Naomi Oreskes: Well, that's exactly right. I mean, we need to mitigate this bec - the planet is going to be fine, the Earth is going to continue no matter what, the question is -
Rhod Sharp: Are we?
Naomi Oreskes: - human suffering and human dislocation. So mitigation is all about minimising the damage, minimising the dislocation, minimising the suffering, and ultimately minimising loss of life.
Rhod Sharp: Okay, Iam [?] says "What was the climatic effect of the production of loess at the end of the ice age?" L-O-E-S-S.
Karl Kruszelnicki: How do you spell that word?
Naomi Oreskes: L-O-E-S-S. Oh yes, that's the very fine - oh, we've found something Dr Karl doesn't know, the very fine silt in China. Uh, so the very fine silt - loess - in China and elsewhere in the world, can have a local effect. Again, it gets back to the dust particles. But typically that dust stays close to the surface, so it can affect breathing in the places where you live, it can irritate your eyes, er, it doesn't get up into the stratosphere though, where it would affect global climate.
Karl Kruszelnicki: Where does it come from?
Naomi Oreskes: It's just extremely fine-grained dust that you get in arid regions where there's fine weathering of rocks that have a lot of fine-grained silt and mudstones, er -
Karl Kruszelnicki: Where did this happen last?
Naomi Oreskes: Er, well there's different places in the world, but at the end of the last ice age, some areas of the planet became much drier, you had the drying out of certain areas, the development of broad areas of desert and in some places, where the rocks and the winds were corrective formed [?], you get this fine silt that can then blow around and create - settle back down and create what are known as loess deposits.
Karl Kruszelnicki: Loess...
Naomi Oreskes: L-O-E-S-S. I guess it's a German word, originally.
Karl Kruszelnicki: Ah, well you learn something every day.
Naomi Oreskes: There you go. Especially when we hang out with you, Dr Karl.
Rhod Sharp: Yeah, here's one for you, Dr Karl. George in Glasgow says "I'd like to know how the ozone layer's getting on these days. Seems global warming has stolen its thunder since CFCs were banned.
Karl Kruszelnicki: Well, it was bad and it was getting good, and now I think it's getting a little bit bad again, it seems to be related - bad things [inaudible] with global warming. Let me explain what happens. The CFCs, um, chlorofluorocarbons, er, end up sitting on called [?] PSCs, which are polar stratospheric clouds, and then when down the Antarctic, er, you have a few things come together. Firstly, you have CFCs sitting on the clouds. Secondly, you have the circumpolar wind current, which sweeps around the Antarctic and traps the air inside, like a giant fence. Thirdly, around September, you have the Sun peeping up over the horizon. It lands on these clouds and starts warming them up. Then they start going through massively destruction of ozone by a pretty well-known chemistry. But the point is that the ozone depletion is confined within that kind of, fence of air. And then you get to November and the fence slows down, and then the wind begins to calm down and bubbles of ozone-depleted air head towards the Equator, often over Australia - we get these big warnings in Australia to have extra sunblock on, when you go out. We did a good thing when we managed to say to all of the forty or so companies that made the CFS stop doing it, Montreal reference [?] -
Naomi Oreskes: Protocol, Montreal Protocol.
Karl Kruszelnicki: Protocol. And then in the third-world countries, people started making this stuff, and now it is one of the most popular, by value, products smuggled into Miami in Florida, beaten only by cocaine, and it's being put into fridges, so you can keep the old fridges going, because it's much cheaper than the new, more expensive friendly-to-the-environment stuff. So on one hand, there has been a little bit of a kick-up in production of these bad CFCs, and then secondly, I was reading a paper which said that there was a link between ozone depletion and global warming, and they weren't entirely separate.
Naomi Oreskes: Yeah, this is really complicated, the chemistry of this is extremely complicated, but CFCs are themselves greenhouse gases, so as the ozone layer begins to recover, and as the CFCs begin to decline, that will actually slightly - tiny, tiny, tiny - slightly slow global warming. But the problem with CFCs is like greenhouse gases they are extremely long-lived chemicals. They stay in the atmosphere for a long time, which is of course why people became concerned about them in the first place. So the ozone layer is recovering but it's going to take a long time and, as Dr Karl correctly points out, we do have to er, control the issue of fugitive CFCs from illegal, black-market smuggling, which is a problem, but still much less than what it was before.
Karl Kruszelnicki: Yes.
Rhod Sharp: I think we've a sort of 64 thousand dollar question here from Stuart in West Lothian, er, Naomi, and he says "How quickly is global warming actually happening, and what effects are we likely to notice in, say, the next fifty years?" And you've got about a minute and a half...
Naomi Oreskes: Ah. Well, great question. It's -well, it's happening right now, like we said before, we've seen just under one degree Celsius warming already, we've seen sea level rise, there's very rapid loss of Arctic sea ice, many climate scientists think we're going to have summer-free - ice-free summers in the Arctic within the next twenty to thirty years, er, many scientists think at least half a metre of sea-level rise within the next fifty years, and virtually all the climate scientists that I know are very concerned about the intensification of extreme weather events such as floods, droughts, heat waves and hurricanes.
Karl Kruszelnicki: Because there's more energy in the system -
Naomi Oreskes: More energy in the system, that energy has to go somewhere, it goes into driving weather, it goes into tropical cyclones - er, we've seen record-breaking hurricane seasons in the tropical Atlantic, we've seen record-breaking cyclones here in Australia - so all these changes are already under way, and I think we can expect to see more of them in the next fifty years.
Rhod Sharp: And a question from Andrew in Warrington, this is going to make you mad. "Did the IPCC sweep under the carpet the many names of scientists who refused to sign their so-called unanimous declaration", says Andrew in Warrington.
Naomi Oreskes: No. Well, first of all, nobody signs anything in the IPCC, the IPCC is not a petition, it's a report. I'm a historian of science, the IPCC has the most comprehensive peer-review mechanism of any group in the history of science.
Rhod Sharp: Right, last question - will you come back?
Naomi Oreskes: If you invite me.
Rhod Sharp: Yes, please.
Naomi Oreskes: Definitely, would love to.
Rhod Sharp: Would love to have you back. That would be great. Naomi Oreskes, thank you so much. Dr Karl, lovely guest, hooray for both of you, thank you.