Climate change: Fact or fiction? | Head to Head

climate change is a fact of life weather patterns are getting wild glaciers are melting and sea levels are rising millions of people around the world are at risk we will respond to the threat of climate related Nations Intergovernmental Panel on Climate Change the IPCC has established that warming of the climate system is unequivocal the threat of climate change is severe and it's not just one study 34 different national academies of science agree that climate change is man-made we have no time to lose in tackling this crisis so where's the debate a few skeptics most of them not climate scientists say all of this is alarmism they're not bothered by rising carbon emissions Professor Richard Linden is perhaps the world's best known climate skeptic he's a professor of meteorology at MIT the Massachusetts Institute of Technology my name is Mihaly Hassan and tonight I'll be challenging professor Linden at the Oxford Union going head-to-head over his controversial view that warnings about the dangers of climate change are just scare mongering can you please welcome Professor Richard Linden a hero to climate sceptics across the world the professor is famously said that he things wrong about global warming we'll know in 50 years and can do something then professor Linden yes are you a climate skeptic or are you a climate denier let's get our terminology straight here you've been called a lot of things what do you describe yourself as well probably neither I mean I would deny the alarmism certainly believe in climate change in temperatures do change so I'm not sure labels are not always helpful so let's move beyond labels and let's just get to the point of why it is in many people's eyes you are so controversial because the mainstream if I can use that word to use another label climate science says the planet is warming man is responsible for much of that warming that's going on right now and we need to cut back greenhouse gas emissions as soon as possible what do you disagree with in those the first two are reasonably uncontroversial although as always there are details I don't think there's a lot of question as to whether temperature has increased a bit over the last 200 years most of the temperature increase in fact has occurred before the impact of co2 is very significant climate is always changing so you know how one views that is perhaps a personal issue that man is responsible for some of that is entirely possible what we do know is there is a greenhouse effect we know that if you add CO to all other things kept constant you should get some warming the estimates are if you doubled co2 you might see a degree roughly whether you could establish how much of what we have observed is due to man let's let me let me on that specific point then the Intergovernmental Panel on Climate Change the IPCC which was established by the UN it said in its most recent report its fourth report which reflects the work of I think 600 scientists in 41 countries they said most of the observed increase in global average temperatures since the mid 20th century is very likely due to the observed increase in anthropogenic a man-made greenhouse gas concentrations it says warming of the climate system is unequivocal as is now evident from observations of increases in global average air temperatures widespread melting of snow and ice rising global average sea level what do you dispute in that okay the statement itself that most of the warming since 50 or 60 19 50 or 60 is due to man's emissions it's possible I think very likely as the IPCC says you know no one knows where their estimate you know 90% likely came from it's very hard to identify the most recent works I've seen suggest that it may be on the order of half now remember we're talking about a few tenths of a degree the real controversy comes with the last part not of this statement but of the statement that having seen this we must cut our emissions because the presumption is that these which i call reasonably innocent statements imply disaster now to put it into perspective let us say that man's emissions accounted let's say greenhouse emissions accounted for all of it that would be entirely compatible with no problem no problem no problem I mean it would say that we might expect by the next century a degree or so and there is little doubt that man has dealt with much more than that okay well on that note you mentioned the question mark about the IPCC professor miles Allen is a professor of GM science at the Department of Geography here in the Department of Physics here at Oxford University he's also served on several IPCC reports how do you respond to Professor Linden when he says where does this 90 percent figure come from the evidence is entirely consistent with most of the warming or indeed all the warming being being driven by the increase the build-up of greenhouse gases in the atmosphere which puts the the future into perspective when we think about the fact that we had 250 years ago four trillion tons of fossil carbon underground we've burnt about half a trillion tons and caused somewhere between three quarters of a degree in degree of what a degree of warming that's taken us 250 years will burn the next half trillion tons in 35 years will burn the next half trillion tons in maybe 30 years and will burn the next we're not going to stop doing this because fossil fuels are such a fantastically useful resource so that's why I see that a mismatch between saying most of the warming to date is due to this buildup of greenhouse gas in the atmosphere and the statement that we won't see very substantial warming in the future if emissions continue because that's exactly what's happening this stuff is building up well first of all I think the IPCC was properly cautious in saying most I think you'd have a hard time arguing for all but even if it were all if you double co2 you create an imbalance in the radiation that is the source of the warming we're already actually quite close to the double my point is it's clearly not going to stop at doubling I mean people who say we're going to avoid doubling co2 I would agree with you it's going to be very hard to do that but if we carry on burning fossils without doing anything we're heading for tripling quadrupling whatever I mean it this plenty of fossil fuel down there that's my point yeah and I mean so yeah and so they keep finding more where does one go from there let me come back to a point you made earlier about the alarmism you don't sound tell armed ISM and you mentioned the IPCC was rightly cautious a lot of people say scientists environmentalists politicians even that the IPCC is too cautious too sober that in fact for example their predictions their modeling their forecasts don't match up to what we're seeing around the world right now you know super storms and heat waves in the United States droughts and floods in Australia England having its wettest year ever last year I mean the IPCC you could argue is too cautious so perhaps not an alarmist enough one of the questions is always is not we've seen warming of a few tenths of a degree we must do something the question is how much do you expect and that is the issue of climate sensitivity that's still a very open question when you say it's an open question is how representative are you of scientific opinion because there is this debate you know we talk about labels look people say your fringe your extreme your marginal you know how ICC reflects mainstream science thousands of scientists across how should I put it on the IPCC and the agreement was we would say nothing that was untrue but there was clearly a bias you were not to attack models you were not to do this unless it was absolutely essential when you say bias it's not just the IPCC is it I mean 34 National Academies of science across the world your countries my countries swear to have they said well India China yeah then what have they have all signed up to the consensus position that the planet is warming man is responsible largely for that warming and that greenhouse gas emissions have to be cut down yeah and it the third and they're all wrong all those all those National Academies are they're all biased most of these bodies have issued that statement without reference to their membership so that's another problem with this issue why have societies that have nothing to do with this issue felt necessary to issue statements and the statements always begin with what I call the trivial agreement and then lead to a policy conclusion that this is dangerous nay right that's one of the question but what's the answer why of 34 National Academies of science put out these statements why is NASA why is the world we NASA has been conflicted on this but what a Geological Society of America why is the International GE I think that's a fair question why do the agricultural societies say this well I own the American Statistical Society I have no idea I do have some ideas they've been told issue a statement on this they are told by who well I'd rather not say to be honest well why because in each case it would be in some ways embarrassing I mean each of them are dependent on the goodwill of the government and if they're told sign on they'll sign on sounds like if you took about 34 National Academies as in countries as diverse as China Sweden America what I mean sounds like a pretty big global conspiracy let me ask you what content is there in what you're saying David Rose is is wanting to come in here David Rose is a special investigations reporter for The Mail on Sunday contributing editor Vanity Fair David first of all I'd like to say that your argument but because 34 academies of science hold of you it must be right is is daft if you go back in history before Copernicus before Galileo you could get a fantastic consensus enforced by the Inquisition that the earth was the center of the universe one of the curious paradoxes of this whole debate is that from the very beginning it gained a far greater political traction than a scientific traction politicians and policymakers began to assume using this so-called precautionary principle a kind of doomsday apocalyptic view of what was happening now with the enforcement of that consensus and who's enforcing well how do you think is living just going to using big work wait wait let me feel comparing it to the Inquisition and Copernicus of it is doing the enforcing David the issue is not whether there is global warming the issue is not whether a law is for some opponent know something good not by human beings the issue is how fast and how far is that happening that consensus is falling apart well let's bring in let's bring in mark Lynas who is an author on this subject and activist he has advised the Maldives government at the Copenhagen summit in 2009 take on board David's point that this is all this is comparable to Galileo Copernicus I actually think there is a very respectable position to be skeptical on every issue you should always ask for evidence you should never just take something as as true because it's given by authorities however there comes a point where the consensus amongst the experts ninety-nine experts out of 100 say that we've got a really serious problem here in terms of greenhouse gas emissions and that's something which concerns me and I could listen to Professor Linden's very reassuring very calm slightly dismissive attitude and say well okay we can carry on pouring greenhouse gases into the atmosphere and carrying on this enormous experiment with the earth but actually I don't think that's a very sensible a very precautionary position and if you want to take a kind of balance of risk approach the fact that we burn 1,100 tons of carbon dioxide and release those into the atmosphere every single second the fact that we're potentially pushing the climate back to where it was 50 million years ago way outside anything that humans have evolutionary experience of actually really does concern me dr. Myles Allen professor Allen who is telling you what to think I've never had anybody threaten me with thumbscrews I find this idea that there's some kind of Inquisition out there that tells scientists what to conclude I find it kind but I find that kind of weird nor has anybody ever told me that lose my funding if I don't know with genuis know well I'm down I'm telling you nobody's out throwing me come scream IV and among my grad students there's always an understanding that they will play down anything that suggests this is not a major problem David's a lay person I'm a lay person if David I are in room together we're taking different positions on this I can't just ignore the fact that when polled 97% of climate scientists sign up to where were they sent home where were they polled were they pulled in a torture chamber you tell me where were they called I don't know it 100 bay I have no idea but I mean you keep posing these questions where's the answer where were they polled well as one of the 97% I'd like to agree with David Rose it's completely irrelevant okay this is not science is not a democracy we don't vote on things we look at the evidence guys are laborers and should ignore the fact that 97 ow I'm not able to ignore like I'm not telling you what to do I'm just saying that's not the way science works I don't think that's a helpful way to frame the discussion professor Linda mentioned papers is it not the case that when a study was done of all the papers that have been published a summary of the scientific evidence - what was it something at 928 papers yeah zero none of them disagree with the consensus they're all wrong as well it's one of the reasons I think you as a citizen as opposed to a scientist should be extraordinarily suspicious what in the world was that study about it was saying when you got down to it and it was you know they've been various such studies they looked through all these papers to see if they contradicted that there was a greenhouse effect and there was warming many of these papers had nothing to do with that at all I wouldn't even have disagreed with it why was something like that trotted out to make you feel there's a terrible problem that should be what you should be suspicious David and professor you're creating this bogus idea of consensus there is a consensus on the basics but no wait wait in a day all in a detail there is no consensus and there is less consensus with every passing month because the areas of further investigation the areas which have been questioned are far less to use another favorite word settled then is sometimes made out mantra narrating patiently I actually don't agree with miles is fine for miles because he is a scientist and professor Lindsay scientists and those of us who aren't and you I was in a position of having to advise a head of state about what to do about climate change he was concerned because he was in charge of a country which potentially you know it's only about that higher but not a meter of up sea level the Maldives potentially this country is going to go out of existence it won't see out this century it rising sea levels continue to accelerate because of the melting of the ice sheets which is also projected as a as a sort of fairly obvious impact as the earth warms now he's not going to read through all of these thousands of scientific papers who does come a point actually where you have to say well the balance of evidence because pretty much all of the experts agree on this is that we should take a very precautionary stance and we should go to the to the international fora Copenhagen which you say to the rest of the world for the sake of our survival as a nation yes you must cut your greenhouse gas emissions okay good I think David was talking about tropical storms the IPCC does agree that the risk of heat waves is in being enhanced or likely to be being enhanced by anthropogenic warming agree there is no consensus that there's a any discernible role of human influence in tropical storms they're different extreme events some extreme events are being made more likely it's very possible that others extreme blizzard risk in the UK may be being made less likely by humans and sometime it the weather is changing I think we can agree on that as someone who involved in the peer review process unlike David and I yeah what's your response to Richards line about these journals being outliers these articles being you know reviewers being brought in etc there's a there is a forgive me a sense of conspiracy I keep getting you know the the IPCC doesn't rely on a single article and we were always really careful you know that whenever I've done I'm sure in the chapters Dick's been involved in as well you'd have been the same we're very careful to look for a range of articles and also do one stand the evidence behind the articles not just to say because the articles there it's necessarily correct and you know so that's why I keep coming back to we need to look at the evidence rather than sort of just looking at the numbers where is the fundamental disagreement do you believe between YouTube given the accelerating rate at which co2 is accumulating in the atmosphere as emissions rise we should expect an accelerating commitment to warming so the statement that we've only seen a little bit of warming so far means it won't matter in the future we won't see any warming in the future flies in the face of our basic understanding of the way the carbon cycle and the time it doesn't work but let me ask you a question about some of the politics of this because you suggested implicitly at the start of this program and elsewhere you've suggested explicitly that some of the climate scientists working in this field are pressured they're doing it for you know political reasons job reasons financial reasons but your critics would say that the reverse is true then in fact the kind of small band of people who disagree with the consensus however you want to define it are actually the people who are getting funding from the fossil fuel industry from Big Oil from Big Coal does it bother you that those are the kind of people on your side no no I I'm glad you brought that up I'm terrifically happy about that I don't know what you're talking about really there's no there's no there's no funding going from ExxonMobil oh yeah there is the career others excellent Koch brothers I've never seen any funding from they've never given any to people who are skeptics sorry they don't give money to the various kind of center-right think tanks in the United States that publish so much stuff about global warming being a myth the Cato Institute the hartline indicate oh they don't get money from these people they make it you know but it's a small amount compared to what the environmental movement puts on I don't know what their bookkeeping is I know in the science community nobody is being supported by ExxonMobil most of the fossil fuel industry has actually gone out of its way to endorse climate alarm BP shell official positions beyond petroleum ExxonMobil has given a hundred million dollars to people who promote this issue okay let me just I've come to you in one second David I just wanna bring in mark there who has in the past campaigned on this issue as well as written about it worked in it the environmental movement doles out far more money in the climate science debate than the oil companies which are not a vested interest I'm not sure that's true but I haven't done the figures either I'm not going to sit here in Coos professor Linz and have taking money from the fossil fuel company I have no idea I'm sure rolled I'm sure mobile play in this debate what oils didn't play any role at all oh I think that I I think I think this there's been strong links with some of the climate skeptic think tanks and and funding from fossil fuel companies that's very well demonstrated so I don't I don't think that's I don't think that's anything that can be denied but the question the question is who's right and who's been the example one here's an example I once had an airfare paid for by I believe ExxonMobil it didn't make a scrap of difference to what I said at the other end of the plane ride I'm sorry I mean this is this is irrelevant it really is irrelevant that'sthat's why I'm not making that same allegation but the point the whole of humanity is dependent on fossil fuels here I took a flight across the Atlantic about two weeks ago I emitted a ton of carbon so I am involved in this business too you know it's not just ExxonMobil we have to we have to find a way to support human civilization without emitting huge amounts of carbon dioxide into the atmosphere I was lost and specifically about the lobbying efforts I think there's lobbying on both sides actually I don't I don't make any great accusations and I think that we have to take perspectives seriously when they are scientific ones and this this is all very mixed up with ideology this is an ideological debate I think professor Linden's made made it fairly clear that he's on a sort of free-market side of the argument which is fine he can hake and have that but we've got to remember where people are coming from they're often they're often speaking very politically when they have this because they're reacting against what they receive as as a sort of state intervention in the economy the things that they think of coming with clinic you're going to bring this part to an end join us in part two of head-to-head where we're carrying on discussion on climate change with Professor Lyndon and our audience will be coming in in part two so don't go away welcome back to part two of head-to-head this week here again in the Oxford Union I'm joined by Professor Richard Lyndon of the Massachusetts Institute of Technology one of the world's best known critics of what some called a consensus position on climate change professor Linden before we go on any further just very quickly we talked about where people should get knowledge from information on the subject where you and some other scientists many other scientists disagree you talked about alarmism earlier if somebody comes and says to you should I stop recycling should ice drive less should I fly less should I try and save more energy around the house would you tell them not to do it what's your advice - I think depends on why they're doing here cuz they're worried about warming Oh for that purpose I would say that it's probably futile these gestures are feel-good gestures there's something rather retrograde about this issue in the sense that you have people looking for omens in the peculiarities the everyday and normal peculiarities of weather and then making sacrifices in order to peas the gods of guy or whatever it is regardless of the relevance of those sacrifices to the issue at hand you're not fan of the environmental movement I know not particularly why not well I distinguish between a concern for the environment and a political environmental movement they occasionally seem to do things that don't seem to particularly help the environment and so I have the feeling that just another authoritarian feel-good movement capitalizing on God knows what good sentiments of people and taking advantage of it it's become a big business in its own right I suppose but no I don't particularly find most of the environmental movement very attractive mark Lynas is here who's a author activist former adviser to governments you've mentioned earlier in part one it's very political when you hear people who are campaigning for climate change worried about the environment worried about what's going on across the world describes authoritarian is that done that you share agree disagree I'm not sure that's so accurate I mean I have my own differences with much of the environmental movement over nuclear power and I couldn't understand why the environmental movement wanted to close down one of our largest sources of low-carbon energy and persist in doing so despite the fact that they're so concerned about climate change there's an obvious conflict there which isn't resolved as you say you you're in disagreement over the means to an end right the end is you share that clock yes greenhouse gas emissions have to come down and I need to prevent exactly and I don't I don't actually I don't think the environmental move it's got it wrong on climate there's some areas where it has but actually I think on on climate they've been they've been very close to the science and that includes groups like Greenpeace I think they've done actually a very good job on climate change what annoys me is the solutions which are proposed are so futile it was actually a reasonable reasonable word for it and the changing light bulbs the energy efficiency the wind and solar only actually we need a much much broader second op away of solutions to that which include ways ways ways to capture all sorts of different kinds of low-carbon energy which have to be cheaper than what we're doing now we need to remember this is about economic growth for the developing world we can't say to the rest of world they have to go backwards China's putting in as much coal-fired power plants every six months as we have in the whole of this country you know this is a huge huge problem but we have to find a way to solve it whilst allowing people the aspirations for growth and the aspirations for solving poverty as a way forward Marx agreeing with you on the futility of the small solutions of course you don't agree with the big solutions either you're so that's part of your answer how should I put it I haven't seen anyone agreed to the big solutions in a way that matters so I think you know in that sense miles and I and Mark and example sorry people don't agree to big solutions you mean government so yeah I look in there partly because people like you keep saying there's no consensus there's nothing needs to be done well how should I put it you have a phrasing of the issue and here I disagree with several environmental groups you know who are saying save the planet we all know that's an extreme statement that doesn't mean anything the planet has survived far more than this and yet what is the value of a statement that's so extreme well it then bypasses any policy issue and anything you do whatever you can because you don't have a planet anymore but in a more rational world we're talking about the potential of some damage a little damage maybe a lot and the question is what do you do and how much can you do and what is worth it to people what you have is of course for the large developing countries like India and China now they're not going to give up their future development for this although their governments take the problem more seriously than you do you see much more how Indian Environment Minister is for example yeah on the other hand almost all proposed measures have very little impact on climate but if you're wrong as you've accepted there's no hundred percent is all uncertainty then you are that these same communities the poorest most vulnerable people in the world are at risk they made you an hour at much less risk yeah I did why I don't get why the why you're so relaxed about this well because as you say you might be wrong you might be right you might be wrong the evidence first it's published science nature I tend to be relaxed so that's a personal issue the second thing about it is if I'm looking at a situation where nobody is actually proposing anything that will do anything for these people except make them poorer then I have to come out on their side and say don't bother with this become less vulnerable true many many economists working in this field don't say that at all they actually say the benefits of tackling climate change now will save money in the long run but actually the best study of that I know and we've had an argument with Bill Nordhaus over it William Nordhaus of Yale University who says waiting 50 years as you propose would cost four trillion dollars yeah yeah yeah out of 30 trillion where he is working to less than one significant figure I mean this was ludicrous if you looked at all those things for an atmospheric physicist he's an economist working there were a carload across on the nose of course he is you know there's no question of that your colleague at the MIT atmospheric science department professor Kerry Emanuel said it just seems deeply unprofessional and irresponsible to look at climate change and say we're sure it's not a problem it's a special kind of risk because it's a risk to the collective civilization yeah I don't believe MIT yes I know it's just not it's not professional just to write it off I'm not writing it off I'm saying if you're in a position where nobody is proposed to do anything except symbolic and you're arguing should you make a lot of symbols you would be doing much better to make people more robust study the problem better ascertain these things don't put pressure on people to find one answer or another and you know stop trying to exaggerate which is being done with a lot of things David let me ask you a question if professor Linden is right and the other climate scientists the 97% are wrong we lose a little bit of economic growth if he is wrong and they're right and we heed his advice much potentially worse consequence isn't there I am not denying that carbon dioxide causes warming but the critical issue that we are skirting around is what works this word futile has been used and the truth is what we have done has been futile we have invested colossal e and are going to invest even more in wind farms wind farms are a hopeless solution wind farms don't work they require backup capacity the cheapest and cleanest way to keep the lights on in this country is building combined cycle gas powered stations and they reduce emissions heavily compared to coal your proposal your solution to a problem of reducing greenhouse gases which in part one you are telling is not a problem because it's not warming anymore the world I didn't say I wasn't warning do you think emissions should come down yes in the long run of course I do okay good I'm glad the howl ruin I'm sure many of your the question is how do we achieve it Myles Allen I think we should really emphasize the enormous amount we all agree on you know the accumulation of co2 in the atmosphere causes warming we can argue about how much well okay maybe there's somebody behind but but I think taken I agree on that any so so hurry with that professor lean bodies think he's agreeing with you either you know how I put it we'll know if emissions have to come down but what I really object to there's a tendency in environmentalism to take something that is bad and demonize it so that no matter how little of it is bad at the same time with co2 the need to diminish it if you really believe it's a problem is huge symbolic gestures are not about that and so you know doing anything you can quote to reduce your carbon footprint okay it's not very easy weighted coming we can all agree that most of the current policy is a futile but that doesn't mean that we don't need a plan to make a transition you eventually let's take a zero garbage economy it's completely insane the way we're approaching this problem but because just because it's insane it doesn't mean we don't need a plan to do it we need a grown-up discussion about other ways of doing it that would work instead of silly conversations about things that don't work okay well on that note since we're trying to find I'm judging from some of the spontaneous interventions we've had so far in the show that we've got a diversity of opinion let's throw it open to the audience now I'm gonna go to the lady there on the end of that bench to my left you know it's not about whether carbon dioxide is rising or going up and down all those factors are variable that's not the issue the issue is actually the oil lobby and their impact on government and that needs to change your viewing as you expressed in part one is that that there really is no oil lobby on this subject you you seem to hold this view that they're not vested interests the oil industry as any industry has interests they have carefully worked out what their interests are and their interests are not in opposing concern over global warming they obviously have an interest in making money staying in business and so on that's true of any business I mean Exxon Mobil's lobbying activities we discussed seem to go against that let's take some more questions in the audience gentlemen here has been waiting since he interrupted earlier I would like to get back to the more practical realistic things and I would like to ask professor lens and to stack up the evidence and both sides of the argument as my understanding is that almost all of the so-called evidence on the alarmist side is based on computer models the consensus view on climate sensitivity is based on models you run models no I mean you don't agree well there's two lines of evidence there's I read of results from models and there's also the range have no I'm sorry no no no no them what is the second line I come to my array so you have this range of model outputs if you go to other measurements there are a number of them the crudest approach is to look at the temperature change historically the change in greenhouse forcing and try somehow to relate that the IPCC actually tried to play that game the problem with that game is there are natural sources of variability which most of the models do terribly on these are things like El Nino Southern Oscillation Pacific decadal oscillation ammo so without that you can't use the temperature record when you attempt to use the temperature record you do come out smaller by a lot than the models let me let me just ask before we go back to the orders wanna go back to the audience and dr. Allen is it fair to say just to get the different perspective that the information on one side comes just from models and the other side from observable experience serve the evidence no I mean the there's two strands of evidence that we bring in as as Professor Linden's described I mean we use what we can infer from the absorb servation and we use the the range of results models I personally as a scientist tend to prefer but we can refer from from observational more and I mean there's various types of observations you can look at the Paleo record you can look at no no you know so most important lines of evidence should be the ones that do not depend on the fudge factors doctor I want ask you a question you disagree I too happen to think mark happens to think some other people have anything the 97% is whatever this does it is important I know you don't agree but let me just ask you from the perspective of a climate scientist and then I'll ask Richard if you were asked where the balance of opinion lies amongst your colleagues on these subjects that we've talked to now on the impact of greenhouse gases on the environment on the need to curve beyond where would it fall the bra balance of opinion as represented by the IPCC reports for example are the Intergovernmental Panel on Climate Change reports those reports actually don't always represent an enforced consensus quite often they explain that so diversity of views on the things and I think the balance of views expressed in those reports is pretty representative of the scientific community as a whole I think by and large that process does a pretty good job of gathering together a full range of views and documenting it but I think one should clarify something the iconic statement you made you know ninety percent certainty etc etc what percent of the ipcc working group 1 Delta even with that question certainly all the authors on the the IPCC report because I mean we're going through this process for the next assessment will will have discussed that sort of headline statement in planar and that's that's how it works that's how it was working in Hobart but so all of the authors who were there will have been discussing that famous arguing over coffee about whether it was justified or not I believe you mean these are really interesting meetings we argue a lot yeah yeah but how many people are involved in that meeting was about three four hundred of us I can't I don't know the exact number because my rebus doesn't go by the numbers it goes by looking at the evidence I use is your position just to be clear is it that there isn't a consensus or that the consensus is wrong what I'm saying is the notion that you take people from widely varying areas most of whom have nothing to do with this attribution issue and ask them to vote on it is it doesn't make it recent we don't we don't sit around and vote I mean yeah and you know that's not the way no no see what I was saying was scientist netting around and questioning each other Mehdi is suggesting that you know this is quote a consensus view of people working on actually when you come to those hundreds it is the coordinating lead authors which is a small group that has needed at least the year I was there look at the lady here to a layperson it looks like the summers are hotter the winters are colder they're more extreme weather events that we have to worry about the seas are rising I just want to know what do you think causes that and if it's not humans then I don't have a car but should my brother trade in his Prius and buy a Hummer or a big SUV can we just go out and drive whatever we want first of all pardon me Hey you know anyone who follows the records knows that the summers are not getting hotter some are cold some are hot the variations occur sporadically over timescales as long as hundred years maybe longer you accept nine of the last ten years of being the hottest excuse me you're confusing a statement about the fact that the temperature rose to something high on the instrumental record by 97 and then it's done nothing and so almost every year at that top layer even if the trend has stopped will be among the warmest years that's apples and pears Miles Allen you've been very keen to get consensus between yourself and Richard Linton in this program do you agree with him that temperatures aren't going up no nobody is saying global mean temperature anomaly over the last 200 years has gone up on the order of three quarters of a degree nobody in this room can perceive personally global mean temperature anomaly if you're here in the UK or you're in Boston the year-to-year variability in temperature can be two degrees four degrees much larger than for the global mean and uncorrelated so the more warm summers we can agree on I don't think so you're dealing with very peculiar series gentlemen there with the glasses on my left in the back row I think that the key issue here is about sensitivity which is the the response of a system to some forcing your vision your view is that the climate sensitivity is low so let's suppose you are right for a second now what about the sensitivity of the climate system added to the sensitivity of the biological system added to the sensitivity of the social system added to the sensitivity of the economic system the sum of all these sensitivities may be very large we might not need a large climate sensitivity to cause big troubles I suppose the more complex we make so you know yes everything you do has consequences and some are bigger than others I would argue that human beings have shown their capacity to produce economic and political instability far beyond their ability to produce environment a we're running out of time so I'm gonna break it down like this nest of people don't accuse me of unfairness who here a group we're going to agree into who he agrees with much of what Professor Linton said it would like to come in gentlemen has been waiting patiently and then we'll go to someone who disagrees is the climate literature and the IPCC assessments are they so completely biased as to make them useless for policymakers or is there something useful that policymakers can extract from them yeah it's good question I wish I could answer it unambiguously but I think Mehdi gave an example of the iconic IPCC statement it's a statement that in my opinion had very little alarming about it and yet it was considered a policy relevant statement that required we do something and here you run into the problem something I used to regard is the Iron Triangle of climate where scientists make rather nondescript innocent statements not particularly alarmist environmental activists will translate it into something alarming politicians will be alarmed and feed money to the side come on scientists are alarmed too there are plenty of scientists are alarmed you know how to code your own colleague at the MIT professor Kerry Emanuel I know I left a risk to civilization I you don't agree with obvious I don't agree with him let's let's try get some more defensive wave to it who here disagrees with what they've been listening to from professor Linz and would like to come in that woman there the back my question is about the link between temperature rise and possible effects such as droughts famines heat waves and I've heard it around 300,000 people a year have actually lost their life due to extreme weather which may be connected to climate change and my question is if there's any link between the co2 that we're emitting and those deaths as far as I know for the regions with good data there is nothing exceptional happening we've always had droughts we always have flood on the point of on the point of the kind of the human impact yeah if as we as we discuss daily if you're if you're right if you're right we've built too many wind farms as David Rose put it if we if you're wrong tens of thousands of people are dying no no the WHS is 150 thousand people a year as a resilience lime it change ready there are lots of people who die I mean as dou Rho is linked to directly to climate change it has yeah I disagree with it it has how shall I put it you can relate lots of deaths to changes in weather and climate that occur I'm not arguing that natural climate variability is not associated with risks I am arguing as to whether there is any evidence that there is anything other than natural climate variability and if there isn't to assign the deaths from climate that have occurred since time immemorial to man's activities today is a little bit specious gentleman there with the glasses been very very patient with the blue jacket let's consider the following propositions that the global warming it's caused by man-made sources okay some people will say this proposition is probably correct you would say this proposition is probably not correct if the statement is true there's catastrophic effect especially for the poorest people in the world who are most vulnerable and so we got to take that factor into consideration if that statement turn out to be true and men thousand and thousand people die would you be able to take that into your conscience what is your threshold value for action what is your threshold for action if things go wrong well it depends on the action if the action is purely symbolic then we better think of a better way to help these people I worry that you're wrong but I do hope for the sake of our planet that you're actually right thank you very much sir richard lindsay for joining us thanks to you all for coming to the Oxford Union for another episode of head-to-head and thanks to you all at home for watching we'll be back in the Oxford Union for another head-to-head goodnight you

Channel: Al Jazeera English

Views: 415,741

Keywords: Myles Allen, climate sceptic, environment, David Rose, oxford union, Richard Lindzen, Head To Head, aljazeera, Mark Lynas, Global Warming, Mehdi Hasan, climate change, Climate change: Fact or fiction?, rise in global temperature, climate alarmism, Climate change sceptic, Climate change skeptic

Id: RAbELlpAxe8

Length: 47min 32sec (2852 seconds)

Published: Mon May 16 2016