Select Committee on Economic Affairs Minutes of Evidence


Examination of Witnesses (Questions 130-139)

Professor Richard Lindzen

25 JANUARY 2005

  Q130Chairman: Good afternoon, Professor. I gather you have had quite a journey getting here and we are extremely grateful to see you in good shape, if I may put it that way. Thank you very much for coming and answering questions. We have got a number of questions that we want to ask you, but is there anything you want to say to start the ball rolling?

  Professor Lindzen: I think the public is being misled as to the nature of the controversy and the science. I have given you a deposition and I will not repeat it at length, but when your Prime Minister assured you that the bulk of scientific opinion was on one side, in many ways I do not disagree with that. I want to clarify that the disagreement is not over whether temperature has been changing; almost everyone agrees somewhere around the order of a half degree change over the last century. No-one disagrees that carbon dioxide is a greenhouse gas and that doubling it would increase the greenhouse effect by about 2 per cent. No-one I know disagrees—there may be a few—that man has played a role in the observed increase in CO2 between about 290 and 380 parts per million. Where the disagreement exists is not over that but over whether that is an alarming statement. The reason that is argued is, in some ways, the following. The people hear about a doubling of carbon dioxide, let us say we start at 280 and go to 560, we are now at 370, 380, and they think of a distant future, maybe not so distant, probably the end of this century. When they hear that this may account for four or five degrees or, depending on your scenario, five-something, they do not question it, and I think there is a very strong reason to question it. That is to say, what is important for climate is not the level of carbon dioxide but how much you have increased the greenhouse effect; they are not the same. When you look at how much we have increased the greenhouse effect since the late 19th century, it is about three-quarters of what one would get from doubling carbon dioxide. I explained this in my deposition so will not bother you with it. The point with that is, if you expect four or five degrees from a doubling of CO2, you expect almost as much, three-quarters as much, from three-quarters of that forcing, and we have seen only a half degree. We know that if you just kept everything constant, doubling carbon dioxide would give you one degree of that, which means that today we should have seen three-quarters of a degree, which is already more than we have seen, but the models are saying we should have seen three, which is about six times more than we have seen. You have a choice in that, namely to say that the models are wrong, they are overpredicting what is happening, or saying the models are right but an unknown process has cancelled the difference. That is where the argument lies. Are we to say that the response today indicates low sensitivity, or we go with an unknown process, cancelling the difference? I think that should be understood very much. A half degree is small on several counts and one of them has to do with a feature that I think laymen somehow have difficulty with, namely, climate varies without any forcing. Things like El Niño, and so on, do not have an El Nin¯o forcer, it is just the system wobbles all of the time, and this is true even in models, incidentally, you run them with no forcing and they wobble. You look at a temperature records and it oscillates and goes through all sorts of things. We do not know what causes it and most of the time we know the system will do it without any cause whatsoever. It means, when you are comparing observations and what is called the null hypothesis, the null hypothesis is would you have the agreement between observations and a picture that just had the random internal variability? That would consist in a horizontal temperature that was broadened to represent the extent of the internal variability, it might be about 0.4 or 0.5 degrees. If then you took these famous curves of temperature, which even though they look dramatic are still half a degree, and broaden them to indicate the uncertainty in the observations, which is about plus or minus 0.15, 0.2 degrees, there is no time when these two curves do not overlap, which means, on the face of it, you do not have any reason to expect the need for any forcing whatsoever. In engineering terms, there is a saying we have a very poor signal to noise. I would leave it with that as a summary of my views on the subject.

Chairman: I think you have pretty well answered the question I was going to ask you, so I will ask Lord Marsh if he would like to start.

  Q131Lord Marsh: One of the problems, as you know, for some of us on this Committee, is that we are not specialists in this field at all, and listening to people like yourself it is fascinating and produces increasing bewilderment at the level of magnificence, so we are trying to catch up on this. To try to get a simple question—we are on only the third meeting of this inquiry—what sort of temperature increases, plus or minus, by, say, 2100, do you think are at issue here?

  Professor Lindzen: It depends on a lot of things. I see no reason at present, with or without Kyoto, why carbon dioxide will not increase. As I say in the deposition, radiative forcing, which is the climate forcing, does not increase proportionately, it increases ever more slowly. I do not expect to see a huge increase in the forcing. Right now, it is close to three watts per metre squared, do not worry about what that means. I do not see it going to much more than four, maybe five. Even if one quadrupled CO2, one is not talking of more than about seven or eight in that range. The evidence so far, contrary to the models, suggests to me that the sensitivity to four watts is of the order of a half degree, so even with the quadrupling of CO2 I would not see more than a degree. It is true that the models are predicting four degrees, but the same models predict three degrees for today, and we do not see that. In addition to that you have other pieces of evidence, I could explain if you wanted but they are technical, they are things that determine sensitivity, that have to do with the time of response to perturbation, so technical issues. They point to low sensitivity. The one thing that points to high sensitivity is models, and these models for economists I find I have to explain. There are in the world of models, I think, a variety of different kinds. There are models that are "constructs" for fields where you do not have fundamental equations, where you put in how you think the system behaves and you use the model to see the complicated ramifications. There are other models, like most of the climate models, which are based nominally on physical laws, where you do not have too much choice in the equations, you have plenty but, the question is, can you solve them? The difficulty with meteorology and climate models is we know the system depends on scales ranging from metres to the radius of the earth. We do not even anticipate a model that can encompass these spatial scales or the timescales, we are talking about thousands of years. As a result, the models we build do not correspond necessarily to the underlying equations and they can produce results that differ from the solutions, and this is particularly important for certain things when you are transporting things, water vapour or clouds. Clouds are the classic case. The IPCC freely acknowledges that there is no model today that gets cloud cover within 40 per cent of what is observed, and 40 per cent in terms of radiation represents something an order of magnitude bigger than the effect of CO2.

  Q132Lord Lamont of Lerwick: It is probably a little unfair but I wonder if I could read you just one sentence of the evidence we had last time from Sir John Houghton and ask you to comment on it. "If you come to the 20th century, you find that the increase in global average temperatures is phenomenal" that is the word he used "compared with any variation over the whole millennium." Could I ask you just to comment on the validity of comparisons over a millennium and, secondly, the use of the word "phenomenal"?

  Professor Lindzen: Could I reverse that to deal with phenomenal? You can give it any word you want, phenomenal, unprecedented, record-breaking; it does not change the fact that it is a half degree, we are talking about a half degree. Do not let words befuddle you. A half degree is to be compared with the model expectation of three. Seventeen years ago—it pains me to think it is going on this long—when the issue started, alarmists wanted to avoid the temperature argument, because they were aware of that. Then they realised that the public did not look at numbers, it was like looking at the stock reports for the day, if the market goes up one point it looks like it goes up a thousand points, nobody can tell the difference. Phenomenal, I think, does not make any sense. It is small. Unprecedented is the other thing, in the millennium. I do not even want to get into that argument. It reminds me very much of, I do not know if you want an anecdote but once I had a friend who went into the Army and he came back home after basic training and was saying he had learned something very strange. In basic training, they were explaining to the recruits what to do if an enemy came at you with a bayonet, and they gave them a technique so that they could always disarm the enemy and kill them. He said he had reached the conclusion that if his enemy has a bayonet and he has a bayonet the first thing he should do is throw away his, because he had a technique for defeating someone with a bayonet. We have thousands of thermometers and we have trouble measuring the temperature to better than a couple of tenths of a degree, averaged over the globe. The record going back a 1,000 years is based on a couple of handfuls of tree rings which only observe growth in the summer. If that is good enough to tell you within tenths of a degree, we should throw away our thermometers. The truth of the matter is, when the people who wrote that drew their uncertainty, you no longer could speak of "unprecedented". The statement that it is unprecedented, by any argument at all, and plenty of people say you cannot measure it back with any meaningful accuracy, still it is not unprecedented, the statement has to be political.

  Q133Lord Lamont of Lerwick: What about isotopes then?

  Professor Lindzen: In general, isotopes are used delta 0-18 for much longer periods. They have very course time resolution by this standard. They would not be too helpful on it. They have tree rings, they have bore-holes, things like that, there are various techniques you can use, but they are all inferior to thermometers and yet they are talking about tenths of a degree.

  Q134Lord Macdonald of Tradeston: Just pitching forward now rather than back. Sir John, talking to us, also asserted that even a one degree centigrade change in average surface temperature in a hundred years would cause all kinds of unacceptable climatic problems. Do you agree?

  Professor Lindzen: I do not. I think he differs even with the IPCC on this. This is a problem of procedure. The IPCC has a lot of people speaking for it. That tends to override what the text actually says. These days, people are saying, "Yes, 2 degrees." It is always arbitrary. The thing I think you have to remember is, here in London, or especially back in Boston for me, or in Paris, or any other place you wish to name, the temperature variability is far greater than it is for the global mean. Each of us is living through fluctuations of several degrees from year to year in the place we live. Moreover, each of us lives through a season, lives through day/night, we are talking about 20 degrees. I find it very hard to believe that, since our agricultural systems, our lifestyle, all encompass such large changes, some global mean is going to swamp it.

  Q135Lord Lawson of Blaby: You have been very eloquent and it is fascinating, but are you a lone voice or is there substantial support for your views among the scientific community?

  Professor Lindzen: I think there is no core of the scientific community.

  Q136Lord Lawson of Blaby: You must speak to your fellow scientists from time to time?

  Professor Lindzen: Yes, of course, all the time, because some of the work is really just quite independent of one's position on this. I think, at MIT, Chicago and other places I deal with, even at the Laboratory for Dynamic Meteorology in Paris, where I spend a lot of time, most people realise the issue is a bit dodgy, but there is a problem, and you say it and it is kind of like being a skunk at the party. In Europe, the Laboratory for Dynamic Meteorology's climate modelling effort exists because of global warming. At the Max-Planck Gesellschaft, their climate modelling effort exists because of global warming. The Hadley Centre exists because of global warming. The only place in the world where there were efforts before global warming was the US, but even in the US the first President Bush responded to the alarmism with two billion dollars a year for research. I do not think you are going to see much objection to the alarmism, but the points of agreement, when they say that scientists all agree, it is basically what I have written in this deposition. Scientists have learned of what I call the iron triangle of alarmism, that they can utter innocent statements, such as the one the Prime Minister said, that are completely consistent with nothing much happening, so they have not compromised their scientific integrity and yet these will be interpreted with alarm, and the body politic, at least in my country, will respond by feeding money to the science. Why would anyone get in the way of that?

  Q137Lord Lawson of Blaby: That I understand very well, but the suggestion is that policy decisions, which might be economically extremely costly, should be based on what you call alarm. So it is not just academic corruption, in the nicest possible way, academics being human like everybody else, put it that way, there is more involved?

  Professor Lindzen: Of course there is. I think, and here I am not speaking as a scientist, we have reached a stage in our country where the belief is, if the politicians want to go along with this and are gullible enough, it is their problem. I think there is that degree of social disintegration.

  Q138Lord Lawson of Blaby: Lord Lamont mentioned an important bit from the evidence that this Committee received last week from Sir John Houghton. Have you seen a transcript of his evidence?

  Professor Lindzen: No, I have not, but I have heard of it.

  Q139Lord Lawson of Blaby: If you have heard about it, is there any comment you would like to make on any of the things you have heard?

  Professor Lindzen: Yes; sure. First of all, I heard him say that my comments are simply verbal and I have presented nothing on it, so I have brought with me my list of peer reviewed publications. In the last four years alone there are 28 on the issue of feedbacks, and so on. The other thing is, he argued, and this relates to the IPCC, that the IPCC Third Assessment rejected the views, and this really presents a problem. I do not know how familiar you are with the procedure, but each chapter has a set of lead authors, of the order of 10 or a dozen. They have a co-ordinating lead author. Each of the lead authors is responsible for a page or two or three, together with two other authors. In some ways, in science, this is one of the most expensive volumes I know. I estimate, per page, in travel expenses alone, plus missed work, it amounts to about $40,000 a page.


 
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