Rt Hon Lord Lilley

    Mr Peter Lilley (Hitchin and Harpenden) (Con): How can my hon. Friend suggest that recent climate changes have anything to do with global warming if there has not been any global warming since 1997, as all the measures of surface temperature indicate?


    Mr Yeo: Of course, with statistics, if we pick the year to suit our argument, we can produce all sorts of short-term pointers. Unfortunately, it remains true that the first decade of the 21st century—2000 to 2010—was the warmest recorded in modern times, so that does not seem to me to be convincing evidence of my right hon. Friend’s claim that the climate has stopped warming. In any event, I believe that it is still clear that there are impacts, as I have said, on human and natural systems that result from recent climate changes—when I say "recent" climate changes, I mean "in the last 100 years or so".


    Decarbonising electricity generation is a critical component of what we need to do if we are to mitigate the worst effects of climate change and, as the synthesis report points out, it is economically affordable. Effective implementation depends on policies and co-operation at all levels. That can be enhanced by the integrated responses that may come out of an agreement in Paris—responses that should link mitigation with adaptation and with other, broader objectives.


    The Secretary of State said of the fifth assessment report:


    "This is the most comprehensive and robust assessment ever produced. It sends a clear message: we must act on climate change now."


    That was also the view of our Committee.


    We focused particularly on the contribution of working group I to the IPCC report. There were, of course, three working groups. One was on the physical science basis; the second was on impacts, adaptation and vulnerability; and the third was on mitigation. The conclusion of working group I was that it was now more confident than ever that greenhouse gas released as a result of deforestation and from fossil fuels has caused much of the warming seen in the latter half of the 20th century and, if unabated, those greenhouse gases will continue to drive climate change in the future.


    The IPCC was criticised for being political and lacking transparency, so my Committee looked particularly into the process and the robustness of the IPCC’s conclusions. Our conclusion was that the IPCC report provides the best summary of prevailing scientific opinion on climate change currently available to policy makers. It is the most exhaustive and heavily scrutinised report so far. We also consider that there is a high level of statistical confidence in the report and that the overall thrust and conclusions of the report are widely supported in the scientific community.


    Of course, as in all areas of science that involve highly complex and dynamic systems, there are uncertainties, but those uncertainties do not cast into doubt the overwhelmingly clear picture of a climate system changing as a result of human activity.


    Ian Lavery (Wansbeck) (Lab): With regard to the criticisms of the IPCC, Professor Lindzen, Nicholas Lewis and Drs Curry and Wyatt, among many others, attended the sittings of the ECC Committee or gave evidence. Would the hon. Gentleman care to explain why he thinks such people were so critical of the IPCC in expressing their thoughts on climate change?


    Mr Yeo: One would have to look at what they have actually said and written about the IPCC. They can probably justify their views better than I can. I recognise that there remains a group of people—I think that it is relatively small—who do not accept particularly the pace at which the climate may be changing.


    I am not sure that it is quite a crowd mentality, but there is a very large number of academics and scientists who broadly accept the thrust of what the IPCC has been saying. Whether some people feel that that produces a peer group pressure to conform, I do not know. I have puzzled a bit over some of the comments and responses that we received when carrying out this inquiry. As I said, we recognised that in all areas of science, there are some doubts—some uncertainties—but the overwhelming consensus is right.


    In particular, the credibility of the conclusions derives from the evidence, just as I hope the work of my Committee is driven by the evidence that it receives. The IPCC received and reviewed thousands of academic papers, which had themselves been peer reviewed, and the conclusion was that there was a clear, unambiguous picture of a climate that is being dangerously destabilised. I thought that the report of working group I was very honest about the levels of certainty and uncertainty, and the "Summary for Policymakers", which of course is of a readable length—it is a synthesis document—is published alongside the full document, which contains all the technical information on which the conclusions were based.


    My Committee has recommended that in future a small team of non-climate scientists should observe the review process for IPCC reports. We also recommended a review of UK modelling facilities. I do not know whether the Minister will be able to give us any information about, for example, what the new Met Office supercomputer may be able to do.


    By way of conclusion, what does the report mean for UK and international policy? First, it clearly reaffirms the scientific basis of the Climate Change Act 2008. Secondly, it has put forward the notion of a global cumulative carbon budget—a maximum level of greenhouse gas emissions for the world to emit safely. We must stay within that level if we are to have a chance of staying within the 2° C average temperature rise that is thought to be safe. Those two conclusions in the report underline the great merit of the UK’s carbon budgeting process. I believe that we can quite accurately claim to be leading the world in that and I think that other countries are getting interested in the way in which we are setting and implementing carbon budgets. That is absolutely in tune with the IPCC conclusions.


    There is also now an overwhelming need for a carbon price. Whether that is derived from carbon taxation, emissions trading or a combination of the two does not necessarily matter. I personally hope that we can make cap-and-trade systems work, because I believe that market instruments are usually the best way to drive investment where it will be most cost-effectively deployed.


    There is work to be done to improve the EU emissions trading scheme, but the inquiry in which my Committee is currently engaged, on linking emissions trading systems, has given us a much clearer understanding of the extraordinary progress being made in China. It is a bit easier to do things when one does not have to consult among 28 countries. The possibility—well, not the possibility, but the extreme likelihood—of a national emissions trading system in China being rolled out as soon as 2016 is astonishing, given that the first pilots are barely two years old.


    We have also had this year the publication of the New Climate Economy report. Again, that is evidence based, and again it underlines the fact that climate change mitigation does not have to inhibit economic growth; the two can go hand in hand. We look forward to our evidence session next week with Nick Stern and Jeremy Oppenheim on that subject.


    We feel that there needs to be a focus on cities, land use and energy. If we can maximise the use of existing low-carbon technology and find new ways to organise and innovate in those three areas, we can address climate change at the same time as continuing with sustainable development.


    Finally, our report calls for, as I have said, the introduction of a strong and predictable carbon price. Anything that the Government can say to reassure us about that and their commitment to it will be helpful. I hope that the Minister can also touch on the prospects for the conference of the parties in Lima next month and look ahead to the Paris COP next year.


    We are, as I said at the start, potentially at a turning point in climate policy, and the Paris COP will be a particularly important stepping stone. If we are to achieve the transition to a global low-carbon economy, a sustained commitment will be required from the Governments represented at Paris from 2015 onwards. If we are to succeed in tackling climate change, the world will have to achieve something that it has never managed before: a consistent annual reduction in greenhouse gas emissions. Every year since the industrial revolution, we have had a consistent annual increase in greenhouse gas emissions.


    I am confident that the science will continue to strengthen, and that the evidence of human activity leading to climate change will become stronger, not weaker. As a result, I expect that public concern, not only in this country but around the world, will intensify. The longer we leave the task of mitigation, the more expensive and disruptive it will be to accomplish. I hope, and indeed expect, that there will be a substantial carbon price in one form or another in the 2020s. The inevitable consequence of that will be that countries that have started to decarbonise their economies early will be more economically competitive, not less.


    Graham Stringer (Blackley and Broughton) (Lab): It is worth understanding what is meant when we talk about the scientific basis for climate change. Essentially, if the climate is changing, it is because the energy budget of this planet is altering. We are taking in more energy than we are radiating as a planet. There is no direct way of measuring that process, so we have to look at indirect measurement, which leads us into a number of difficulties. One only has to think about the ice ages to realise that the climate has always changed. There is natural variation, and if the planet is taking in more energy than it is radiating, that will inevitably lead to climate change that is not a natural variation.


    As Professor Trewavas has said, there is not a scientist on the planet who can measure and distinguish between natural climate variation and anthropogenic climate variation, so we are in serious difficulty when we talk about the scientific basis of climate change. That has become an area of great controversy and enthusiasm from certain parties. I am—or at least I was—a scientist. As I have debated science in this place and elsewhere, I have come to the conclusion that science and politics are a bad mix, and that one tends to contaminate the other. Science is about the search for truth. Good scientists, if they are proved wrong, will shout, "Alleluia!" because they are pleased that the boundaries of knowledge have been pushed further. Politics is about winning the argument; it is about my side beating the other side.


    Unfortunately, in the debate around climate change, some politicians and so-called non-governmental organisations have distorted the science and pushed arguments in a non-scientific way. A current example of that—it is not immediately to do with climate change although it could be—is the case of Professor Anne Glover, the former scientific adviser to the President of the European Commission. She has just failed to get her contract renewed because she took a view on genetically modified foods that Greenpeace and other groups did not like, and those groups lobbied to remove scientific advice from the Commission.


    I think we will see that various activist groups have behaved in a similar way in the discussion about climate change. Because of that, I proposed a number of amendments to the Energy and Climate Change Committee report, which fell into three categories. The first was about the political nature of the report that the Intergovernmental Panel on Climate Change produced.


    The second was about what passes for science, given the problem I talked about before of direct measurement of the planet’s energy balance and climate change. The third was about the consequences for this country’s energy policy.


    Donna Laframboise provided a lot of written and oral evidence to the Committee about the political nature of the IPCC. In drawing up the final report, representatives of 100 Governments met in secret for a four-day session. They changed the report, reducing it by 700 words and increasing the number of pages. Astonishingly, given that the report was supposed to be based on science, they reverse-engineered it to make it consistent with a summary that was a series of political compromises, where words were put up on whiteboards and crossed out according to the agreement or lack of agreement between the representatives of the different countries.


    That leads me to two conclusions. Why should an intergovernmental process that produces policies that may lead to trillions of pounds of expenditure around the globe take place in private? It should not. Why should a summary of a scientific subject be produced by Governments rather than by scientists? The IPCC claims that it is a scientific body, but it is not. It is an intergovernmental body that reaches compromises, just as politicians reach compromises. I would scrap the IPCC and move to a science-based body that published summaries of current climate science more frequently.


    Ian Lavery: Is my hon. Friend suggesting that he has no confidence whatsoever in the IPCC’s recommendations?


    Graham Stringer: I would answer my hon. Friend in two ways. First, I would not detract from the basic scientific papers that lie underneath the report. Those papers are produced, by and large, by reputable scientists who are doing their best in a difficult area. Secondly, I ask him to consider the fact that the most significant, headline conclusion was that we should have more confidence in the IPCC’s conclusions now than we did previously. However, its prediction about global temperature increasing over the past 13 or 14 years has been wrong; it did not predict a flattening of the temperature curve. It is strange to conclude, when it has got something so badly wrong, that we should have more confidence in its results, and I do not. To say that I had no confidence would be very strong if that was based on decent scientists doing decent work, but I argue that the process is seriously flawed. That is the IPCC.


    Staying with the science for a moment, one of the amendments that I proposed to the Select Committee report was to say that we do not really have 97% consensus that we are heading towards catastrophic climate change. I base that, although there are other areas that we can look at, on Robin Guenier’s evidence to the Committee. He carried out a survey of all the reports that consider the views of climate scientists, and he concluded:


    "In summary, the inadequacy of useful evidence means that the extent to which the SPM reflects climate scientists’ views is both unknown and likely to continue to be unknown."


    That is because there has not been a decent survey.


    "Therefore it’s impossible to provide a reliable answer to the Committee’s question."


    That question was whether there was a consensus.


    "However, such evidence as does exist indicates that the answer would probably be that AR5 reflects the range of views among climate scientists to only a very limited extent."


    That partly answers my hon. Friend’s question.


    The regularly cited figure of 97% consensus comes from a report by Cook based on an old survey of about 12,000 pieces of scientific literature. Cook looked at the literature, and if a scientist stated that they believed carbon dioxide to be a greenhouse gas, he claimed the paper in support of the consensus that catastrophic global warming is happening, which is a non sequitur—it clearly is not the case. When we look at the other papers surveyed by Guenier, which I can list if necessary, there are various views from different scientists and groups of scientists. No survey can be absolutely categorical about the views of climate scientists, but when those views are assessed, they certainly do not come out anywhere near 97% consensus that catastrophic global warming or climate change is happening. We can put that to one side.


    If we look at where we are left with the science, given the previous problems, we have to consider climate models, because we cannot directly measure the planet’s energy balance. Some of the evidence given to the Committee seriously criticises the climate models. At the time of the report, the Committee did not have the views of Steven Koonin, an adviser to President Obama’s Government who is a specialist in such computer programs. He goes through in great detail where the problems are in the computer models. He points out that the resolution of the computer models is 60 miles, and there can be many types of weather and weather changes in a grid 60 miles square. To work out what is happening, the models start with basic figures and then begin guessing, and it is no better than guessing because they have to work out the average cloud cover based on the humidity and changes in temperature over such large areas, which have huge variations. Basically, the situation can be fiddled within the grid. By and large, the temperature changes over the past 100 years or so vary in such models by factors of three. That does not prove that one of the models is right, because some 55 models are being used out there, but it does show that there is no consistent modelling.


    Do the models allow us to predict or understand what is happening? They predict the reduction in the Arctic ice cover but not the increase in Antarctic ice, which probably outweighs the reduction in ice at the north pole. The models do not predict the completely even rise in sea levels over the past 100 years—the rise has consistently been about 1 foot a century for some time. The models predict that the surface temperature in the tropics should increase, but it has not. There are many serious problems with the models, and one has to realise that there are fiddle factors.


    The Chairman and other members of the Committee are convinced that the models are the basis on which we should predicate the whole of our energy policy. Our energy policy is to put up the price of fuel for the people I represent, and they are some of the poorest people in this country. We are trying to hit emissions targets on carbon dioxide, and at the same time we are deindustrialising the country, so we are not putting less carbon dioxide into the atmosphere; we are putting more carbon dioxide into the atmosphere. That policy—I do not want to overuse the word "catastrophe"—has perverse consequences. If people genuinely believe that carbon dioxide will lead to a global catastrophe, we should not be pursuing the policies that we are now pursuing. The drive for renewables, where there are indications that current research may lead to better renewables in future, is putting the security of our energy supply at risk. So the three key factors of the Government’s energy policy, based on many of the IPCC’s conclusions, are perverse.


    I lost the votes on the amendments that I proposed to the Committee—I often lose votes, which I do not mind because that is the nature of politics—but I ask my hon. Friends and Government Members to address the points. There simply is not a 97% consensus. We are responsible for putting more carbon dioxide into the atmosphere, and there is a great deal that we do not know about what is happening in the atmosphere.


    Mr Peter Lilley (Hitchin and Harpenden) (Con): I apologise to you, Mr Betts, and to my hon. Friend the Member for South Suffolk (Mr Yeo) for arriving a few minutes late and missing some of his opening speech. It is a pleasure to follow the hon. Member for Blackley and Broughton (Graham Stringer), who made an important contribution to this debate, as he does to the Committee’s deliberations. The report, of course, was not unanimous. Both he and I voted against it. I think we were able to secure the inclusion of only one of his amendments, but that is not because either of us denies the basic science of the greenhouse effect. He can speak for himself, but we are both scientists by training, which is a characteristic that is not shared by most members of the Committee. We do not dispute the greenhouse effect, nor did any of our witnesses. However, great uncertainties remain about how much warming a given increase in greenhouse gases will cause, how much damage any temperature increase will cause and the best balance between adaptation and mitigation in response to, or in pre-emption of, global warming.


    The main bulk of the IPCC technical report recognises those uncertainties, and the report is simply a useful compilation of research in the field. My criticisms are about the summary for policy makers, which is far less balanced than the report it purports to summarise. The hon. Gentleman explained the process by which the summary was produced, which may be why it is so less balanced. The summary is essentially a document of advocacy, and it achieves its objective of influencing policy makers, as its title indicates, by the selective use of facts and the omission of quite a lot of the stuff in the main report, including some of the most significant changes, which are simply not drawn to the attention of policy makers. I am not the first to criticise the IPCC process.


    Ian Lavery: This is a general point. Would the right hon. Gentleman describe himself as a climate change sceptic?


    Mr Lilley: Yes. I normally call myself a lukewarmist. I believe that the climate will warm a bit, which will probably be quite beneficial to parts of our country, although it could pose problems elsewhere. I do not deny that double the amount of CO2 in the atmosphere will increase the temperature by 1° and a bit, plus or minus any effect due to positive or negative feedbacks. However, I do not think that the evidence shows that the change will be very large. I will come to that.


    It is not just climate sceptics and I who have been critical of the IPCC’s tendency to exaggerate. Following the discovery of inaccuracies, use of grey data and so on in AR4, the fourth assessment report, which forecast that all the glaciers in the Himalayas would melt in 35 years rather than 350 years, the InterAcademy Council—the council of all the main scientific academies in the world, including our Royal Society, the US scientific bodies and so on—carried out an investigation of how the IPCC worked. The IAC was critical, particularly of authors who


    "reported high confidence in statements for which there is little evidence".


    It is not just fellow sceptics and I saying it; all the scientific academies of the world, which by and large have signed up under some political pressure to rather unscientific statements about global warming, have considered the IPCC report and concluded that some scientists, although not all, tend to report high confidence in statements for which there is little evidence. The IAC therefore recommends:


    "Quantitative probabilities (as in the likelihood scale) should be used to describe the probability of well-defined outcomes only when there is sufficient evidence. Authors should indicate the basis for assigning a probability to an outcome or event (e.g., based on measurement, expert judgment, and/or model runs)."


    No such basis for assigning enhanced probability was given when the most recent IPCC report came out. Its headline conclusion was that the evidence for human influence has grown since the fourth assessment report, and it went on to attach increased likelihood—categorised on the scale as "extremely likely", rather than the previous "very likely"—to the possibility that human influence has been the dominant cause of the warming observed since the mid-20th century. That was the overall headline assessment to which the IPCC wanted policy makers to respond. However, it is hard to back up that conclusion from the substance of that report. Since the last report, we know what has happened.


    Dr Alan Whitehead (Southampton, Test) (Lab): Will the right hon. Gentleman give way?


    Mr Lilley: I will make this point, and then I will give way.


    Since the last report, the earth’s surface temperature has not warmed further; indeed, it has not warmed during the entire period of the IPCC’s existence, since 1997 or 1998. There has been a hiatus in warming, yet during that period since 1997, one third of all the carbon dioxide ever emitted by mankind has been pumped into the atmosphere. We have had 17 years to test the effect of a third of all the CO2 we have ever emitted, and there has been no increase in temperature. That does not mean that the global warming thesis is dead or wrong—I believe in it—but it does mean that it is not the dominant factor. It means that during that period, other factors were masking any warming due to the increase in CO2.


    Dr Whitehead: I would like to get something clear. Is the right hon. Gentleman suggesting that the issue relates to the difference between "extremely likely" in the fifth assessment report and "very likely" in the fourth assessment report? That is, does he stand by the idea that anthropogenic global warming is very likely, although he might not stand by the idea that it is extremely likely, or is he saying that it was not very likely in the first place?


    Mr Lilley: I am saying that in its use of those terms, the summary for policy makers has not responded to the recommendations of the InterAcademy Council report.


    Dr Whitehead: But does the right hon. Gentleman stand by "very likely"?


    Mr Lilley: I never made that statement. I think that it is uncertain how much of the heating that has occurred since 1950 is due to CO2. Some of it is; perhaps half of it. I do not know.


    It is the word "dominant" of which I am most critical, and the idea that human influence is the dominant factor. During that period, the whole lifetime of the IPCC, there has been no warming, yet a third of the CO2 ever emitted by man has been put into the atmosphere. That does not seem to be evidence for being more certain; it seems to be evidence for being a little more qualified in stating that CO2 may be the dominant factor. It clearly was not dominant during that period. By definition, a period with record emissions but no warming cannot provide further evidence that emissions are the dominant cause of warming.


    A number of other, quite important factors have simply been omitted from the summary for policy makers. Although the IPCC says that there is increased certainty, it does not tell us, except obliquely in a footnote, that for the first time, the authors of the IPCC report are unable to agree on a best estimate of how sensitive the climate is to increases in CO2. In previous reports, they have always been able to agree a best estimate, but this time, there has been so much disagreement among them that they have been unable to reach one. When I was a Secretary of State being advised by experts, if there was disagreement among them, I wanted to know about it; I did not want it hidden from me. If the disagreement was new and had not been present in their previous advice, I doubly wanted to know about it. However, that was not mentioned in the summary for policy makers, which is not a good way to ensure that policy makers are well-informed.


    Nor does the summary mention that in the body of the report, the IPCC’s medium-term forecast for temperature increases to 2035 is below that given by the climate models. In other words, the experts used their judgment to say that in their opinion, the climate models are wrong. They came up with a forecast below the models, and they explain that the reason is that the models have been overheating. Their forecasts have not conformed to the facts. I would have liked to have that pointed out to me in the summary for policy makers, but it was not. I would also have liked some explanation why, after 2035, the IPCC assumes that the models will be right and will no longer overheat. If they have overheated in the past and are expected to overheat until 2035, why are they expected to be right thereafter?


    The overheating is serious, and it is not just during the period of the hiatus. Over the past 35 years, the models studied by the IPCC have collectively run an average of 15% too high. They are significantly in error. That, too, is something that I would have liked pointed out in the summary for policy makers, so that one would know, when talking about model estimates, that they have been consistently and significantly wrong for 35 years. But that was not pointed out.


    According to one of our witnesses, the most significant fact in the whole AR5 was the new evidence about the impact of aerosols. We now have evidence from satellite observations that provides more certain estimates of the prevalence of aerosols in the atmosphere and their impact and suggests that they produce less cooling than was previously assumed. However, there was not time to use that information to rerun the model—sometimes the models take months to run—so none of the models take into account the latest information on aerosols. Had they done so, they would have produced an even higher forecast for future warming, because the future warming forecast involves the warming created by CO2 less the cooling created by aerosols. If there is less cooling by aerosols, the forecasts would be higher—that is, more wrong—in the past, and probably even more wrong in future.


    Indeed, given that we know what the actual amount of warming has been, if that warming—0.8° C since the industrial revolution—is the result of carbon dioxide, the model suggests that if it had been down to CO2 alone, the warming would have been something like 1.2%. However, because of the old estimates of aerosols, an offset of 0.4% is assumed, which is why we observe the 0.8° C figure. We know the 0.8 figure is true. If we now have better estimates, so that instead of 0.4% the offset is 0.2%, that means that the CO2 effect should have been forecast as being 1° C rather than 1.2° C or 1.4° C. That is a significant change—new evidence—that should have been brought to the attention of policy makers but was not.


    Nor was the fact that most recent empirically based studies of the sensitivity of the climate to CO2 have come out with lower figures. Indeed, since the report came out, a study of all the estimates of the sensitivity of climate over time has been made—in the form of a chart—and it shows that the estimates are progressively coming down. In other words, the likely feedbacks must be less and less, as estimates become more accurate and indeed the period with no warming extends. Again, I would have liked to know that in the SPM, rather than it being hidden away in a 1,000-page report, which by definition the policy makers are not expected to read.


    We know that there has been a pause in global warming since 1997. My hon. Friend the Member for South Suffolk says that is somehow a statistical fabrication. If I want to know how long this table is, having climbed up the steps to get to it, when I get to the level bit, I measure that to see how long the table is; I do not include the rise before and I do not exclude some of the flat bit. The length of a plateau is the length of a plateau, and it is 17 years. That is quite simple.


    If over that 17 years, the effect of CO2 has been offset by other natural factors—I am not denying the effect of CO2; I am saying it must have been offset by other factors. [Interruption.] Presumably, the hon. Member for Southampton, Test agrees with me; if he would like to intervene to disagree, he is welcome to.


    Dr Whitehead indicated dissent.


    Mr Lilley: No. He agrees with me.


    Dr Whitehead: I merely pointed out—unfortunately, from a sedentary position—that it is a little dangerous to start talking about plateaux in the context of what has been probably several hundred years of anthropogenic effects. Indeed, at any particular stage, it would have been possible during that period to select particular years to make particular points. However, that is not the greater point that needs to be taken into account; that is about looking at the overall effects over a period. The right hon. Gentleman persists in talking about plateaux when, in overall terms, that is what happens on occasions in a much longer period, and it can be easily demonstrated over the period.


    Mr Lilley: I entirely agree with the hon. Gentleman. There are periods when temperature has been rising and periods when it has been falling, for example from about 1945 to the early 1970s. Then there was a period of about 25 years when it was rising and everyone said, "That 25 years is very good evidence." They did not say, "25 years is far too short a period." They said, "Oh, that’s it. That’s going to go on." The Met Office gave us forecasts for a single decade of how much things were going to change; it was confident that this was a continually rising trend.


    However, there is a period when it has been flat. But if the underlying greenhouse effect has been rising, that means that natural factors are of the same magnitude, and those natural factors—over the long term—will cancel out other factors. Therefore, the upswing in natural factors may have been contributing to the warming in the 25 years of warming, and that should have been brought to the attention of policy makers but was not.


    The hon. Gentleman says that I go on about flat periods. However, far worse than the SPM is the press release issued by the IPCC itself, which says:


    "Warming in the climate system is unequivocal and since 1950 many changes have been observed throughout the climate system that are unprecedented over decades to millennia."


    It goes on to say that the period of


    "the last three decades has been successively warmer at the Earth’s surface."


    So it is talking about warming.


    The fact is that the warming since 1950 has not been unprecedented; it is almost exactly the same, over exactly the same period, as the warming that occurred from the end of the first world war up to the second world war. How can we explain the fact that there was a similar amount of warming when there was very little emission of CO2 to a period with an identical amount of warming when there was a lot of CO2? It must mean that other factors are relevant, and those other factors are of the same order of magnitude in their impact on the climate as CO2.


    All I am saying is that these things should be drawn to the attention of policy makers. Policy makers should not be treated as children; they should not be fed a line; they should not be given a document that purports to be a scientific document, but is actually an act of advocacy, achieving its end by selective use of facts and omission of a lot of the evidence that the experts who produced it took a great deal of time and a thousand pages to assemble. Sadly, that is why the report from our Committee sounded more like cheerleading than holding to account a body that must be held to the highest standards, and not excused if it happens to agree with our own opinions.


    Dr Alan Whitehead (Southampton, Test) (Lab): Mr Betts, I also have to apologise to you for my late arrival this afternoon, and in particular for my inability to heart the contribution to the debate of the Chair of our Select Committee. Nevertheless I predict, although not with absolute certainty, with a fairly high level of certainty that I will probably agree with him in what I say.


    I was detained in coming to this important debate by a discussion I was having on Japanese knotweed; to be precise, it was a discussion on Radio 2. On arriving here, I was thinking that perhaps Japanese knotweed is not such an awful metaphor for our debate today, inasmuch as it is here, there is a considerable amount of disagreement about its effect and there is a lot of scientific activity going on at the moment to try to clarify and qualify that effect, including studies to see what insects predate on Japanese knotweed. And there is some uncertainty about whether the effects of insects on Japanese knotweed are real, and about whether "urgent" action needs to be taken, or just "reasonably urgent" action, or "not very much action at all". So there is quite a lot of debate about Japanese knotweed.


    However, what we do know, with a reasonably high degree of certainty, is that Japanese knotweed is very invasive; it uproots our houses and properties, and needs to be dealt with. Indeed, if a surveyor came along to me if I was attempting to deal with my house repairs and said, "It’s very likely that Japanese knotweed is undermining the foundations of your house," I probably would not say, "I’m not going to do anything about this, because I want to wait until I know that it’s extremely likely that it is undermining the foundations of my house. So I will just let the stuff get on with it until I am absolutely certain, on scientific grounds, that it is extremely likely that my house will be done over." Instead, I would probably say, "Well, ‘very likely’ is pretty much good enough for me. I’m going to do something about this, and get my house sorted out."


    That in particular was why I intervened on the right hon. Member for Hitchin and Harpenden (Mr Lilley) during his contribution, which was about the difference between the fourth assessment report and the fifth assessment report on the degree of likelihood. While it is true that there has been a change between those two reports in what the guide for policy makers is indicating in terms of just how great a degree of emergency we face as far as the effects of anthropogenic global warming are concerned, the assessment has indeed moved from "very likely" to "extremely likely". As I have underlined, even if someone did not really think that "extremely likely" was absolutely the starting point for taking any further action, they might be rather alarmed by what has happened previously.


    What I then worry about is those people who look at the IPCC’s fifth assessment report, just as the Select Committee has done, and who start to raise concerns about it in the way that we have heard today. It is not that those concerns are illegitimate or necessarily entirely out of court, in terms of discussion. However, after that we have to say, "What might some of those concerns amount to, depending on how they are depicted, as important or otherwise, to what is—as IPCC’s fifth assessment report is—a transition of a series of scientific documents, discussions and conclusions, into a document that has some relevance as far as policy makers are concerned?" Indeed, that is precisely the equivalent of a discussion on the science of Japanese knotweed and the surveyor’s report.


    Graham Stringer: Does my hon. Friend agree that it would be better if scientists summarised the science, not politicians?


    Dr Whitehead: It is better that a report produced for policy purposes is a synthesis of what scientists and others are saying and concluding. Indeed, that is exactly what our report concluded.


    Beyond that, we then come not to the question of what concerns there might be about some of the detail of the fifth assessment report and its policy summary, but to one important element of scientific method. I should say that I am a social scientist, not a scientist scientist, but I certainly would always have regard to scientific method in my researches and thoughts on a matter, and would be pretty much guided by scientific method and principles of probability and various other things such as those. The important element is that there are always outliers in any scientific discussion. How could it be otherwise? That is what science is about. Science is never unanimous. Indeed, the whole of scientific method is to take something that looks unanimous and test it to destruction and see whether a new consensus emerges from that—and that in turn is tested. There are always outliers and always people who are testing science, and always people who will disagree with a conclusion.


    In terms of what science does in informing policy makers, the question is how to best get to the best science that there is, currently, to inform something that will not have 100% certainty behind it but which is, as I have described in terms of what people do about their house, an imperative that they may have to act on, without 100% certainty, but with a high degree of probability behind their actions. That is essentially what the IPCC fifth assessment report is about.


    Mr Lilley: I intervene to offer the hon. Gentleman some advice on surveyors. If a surveyor is asked to do a report, the probability is that he will find some damp, some rot and something to do, because that is his job; he is a professional alarmist. I have a surveyor coming in a week’s time and I am paying him a fee just for the survey, so that he has not got an incentive to create work. In a sense, the IPCC is a bit like that. It is in the job of producing things that show that CO2 is an alarming proposition.


    Dr Whitehead: The right hon. Gentleman is exactly right, but I think that perhaps he slightly misunderstood the process that follows that. If people get a surveyor in, it is quite possible that they will find some things wrong with their house. The probability, in terms of that surveyor’s professional background, is that even if the surveyor finds a few things wrong with their house that they do not think are particularly wrong, he is probably right. The question is to what extent they take action following what the surveyor says. The right hon. Gentleman appears to suggest—I would not put words into his mouth—that people can safely say, "This surveyor is just after his own interests in surveying my house, so I can confidently put this in the bin and purchase the house down the road that the surveyor told me is a complete turkey, safe in the knowledge that he is trying to make money. Therefore I can completely disregard what he said. And then, when my house falls down, I will be sorry about it, but I am safe in the knowledge that I wasn’t taken in by that beastly surveyor, who was trying to make some money." I am not sure that the argument really follows in its fullness. I want to concentrate on that for a few moments in respect of the IPCC report.


    One concern about picking small holes in a report and bringing outliers on board in emphasising the size of those holes is that, eventually, people might say, "Perhaps those holes need to be looked at"—indeed, the Committee in its report identified a number of areas in the procedures of the fifth assessment report and the summary following it that did need looking at and action for the future—and they fairly soon elide into talking about conspiracy theories and asking, why would people have falsified data and put things into this report? Or why would scientists from across the world have congregated together to overthrow their own scientific method and start putting bogus material into reports and trying to smuggle such material into summary reports, to falsify those and affect the gravity of action that may be required for policy makers?


    The problem that then arises of people moving away from citing holes and difficulties to saying that the whole thing is therefore a bunch of falsified bunkum. I have to say that hon. Members contributing to this debate in a contrary position from that of the fifth assessment report and the Committee’s conclusions seem to be sailing rather close to the wind on that. As soon as people get into the area of conspiracy theories, that is the complete overthrow of science. Conspiracy theories and science are mutually self-destructive.


    We have to accept, surely, that this IPCC fifth assessment report was carried out by honest scientists from around the world, who honestly put forward what they did because they had found it to be so in their view, and that the collocation of those various views—a difficult process in its own right—was also undertaken by honest people coming to particular conclusions. Unless we think otherwise, we will eventually be in the position of saying, as I have mentioned, not necessarily that it is extremely likely that anthropogenic action on the climate is the cause of global warming, but that it could be "Very likely", "Maybe", "Extremely likely", "Maybe not", "A bit between the two", or "Very likely that it is very likely", and then we are in no man’s land. At that point, people may start saying, "If they are all fabricating these things and the evidence really is a tissue of misrepresentation and lies, then we have no guide at all for policy in future," which is, after all, what we ought to be discussing in this Chamber.


    Mr Lilley: Normally, the hon. Gentleman is good, in that he follows the logic of my questions through, sometimes to points that I did not want him to reach, but here he is putting words into my mouth that are the exact opposite of what I said. I did not say anyone had falsified anything; I simply said they had excluded material that was in the main report from the summary for policy makers. I hope he will clarify that. I was not accusing anyone of inventing falsehoods.


    Dr Whitehead: The right hon. Gentleman is right. He will recall that I said that it sounded to me a little bit like that was the direction in which some of the contributions might be moving. I do not personally accuse the right hon. Gentleman of taking that position. However, a number of other people—not he—have taken and do take that position and it seems to me that they are, as a result, hopelessly adrift in terms of what we might or might not do.


    Graham Stringer: I hope that my hon. Friend does not mean me. I hope I made it quite clear that, as far as I am concerned, the scientific papers are produced—unless evidence shows they are not—by scientists of integrity. Where the problem lies is that representatives of Governments take a large amount of that science and reach political compromises, which is bad for the production of a document. That should be done by scientists, because they would produce a different document. Because they represent the view of their Government, Government representatives stop information from those scientific papers getting into the report. That is not a conspiracy; that is political process.


    Dr Whitehead: My hon. Friend sets out a process that seems remarkably similar to every single bit of policy work that ever takes place anywhere in the world on pretty much anything. There is a scientific process and if scientists wish to inform policy makers who are involved in that process, those policy makers will be involved in a process that is less than perfect in relation to what the science says. It is a combination of what is possible, what the policy is that is informed by the scientific process and, most importantly, whether the policy makers should wait for the science to be absolutely perfect before they do anything. My hon. Friend is coming close to saying that unless the science is perfect and scientists can have a sign-off on absolutely everything that goes on to the desk of the last policy maker, we should do nothing.


    Ian Lavery: I am probably the only person here who is not a scientist. Politicians who, like me, are not scientists rely on evidence from scientists on both sides of the argument, because we, as politicians, make decisions based on what the scientists tell us. Where does that leave me?


    Dr Whitehead: My hon. Friend is in exactly the position that I have just described. He is a policy maker who has to be advised by the best science. Given the full and informed contributions that he has always made to our Select Committee considerations, he is the complete embodiment of that process. Policy makers have to combine how they see the landscape with what the science is advising about the landscape and make judgments about what should be done in relation to those two facts in their role as policy makers. That is not and should not be a surprise to anybody. There is a real link between what the science is telling us and what we as policy makers have to do about it.


    Graham Stringer: My hon. Friend is being generous with his time. The British Government do not follow the same process as the IPCC when it comes to scientific advice. The Government have a scientific adviser who gives independent advice to the Cabinet and the Prime Minister. Each Department has a scientific adviser and specialist committees. They do not wait until there is certainty; they produce the best available science at the time and Ministers take decisions on that advice. If the IPCC followed that process, I would be a much happier person, but it does not do that. It introduces politicians into the scientific process. That is where it goes wrong, and that is not describing a conspiracy.


    Dr Whitehead: My hon. Friend describes the sort of process at an international level that to some extent goes on in Her Majesty’s Government. The document that he refers to, which was referred to by the right hon. Member for Hitchin and Harpenden, is headed, guide for policy makers. It does not purport to be the scientific document. The scientific documents, as we have agreed, are elsewhere.


    Mr Lilley: It is a "Summary for Policymakers".


    Dr Whitehead: It is a summary and a guide for policy makers. If the right hon. Gentleman looks at the document, he will see that that is exactly what it says in those documents. That is how it was announced and how it was reported to the United Nations. Indeed, it is how the United Nations Secretary-General described it. It was specifically set out on the back of the various documents and the detailed material that it was a further document over and above that work, forming a bridge between the scientific material and the guide for policy makers, and that is exactly how it should be seen.


    As far as I am concerned as a policy maker, the fact that the IPCC report concluded that the anthropogenic effect on global warming is either "very likely" or "extremely likely" impels me to act, for all the reasons I have described. The Select Committee report was attempting to ascertain the overall veracity of what the IPCC’s fifth assessment report was about, how it translated into policy, possible difficulties and what needs to be done next. That is essentially what our report talks about, and that is good enough for me.


    We need to take decisions on how we deal with the decarbonisation of our energy and on limiting as radically as possible the emissions that will add to anthropogenic global warming. Those are the direct policy implications that this House needs to look at closely, and we will unpack that further to say, "We may have disagreements about exactly how we limit the decarbonisation of our energy supply and the many different ways of doing it, but we will have a separate policy makers debate"—as my hon. Friend the Member for Wansbeck (Ian Lavery) has alluded to—"on the best method of doing that." Unless we have an overarching guide where we are clear about what we are doing, most of the rest of that conversation will not make a great deal of sense.


    The best endeavours of pretty much all the scientists involved in this area around the world are to get to grips with finding out what is happening, why it is happening and what we should do about it, and we in this Chamber should commend that work and not seek to draw false conclusions from it or pick holes in it that are of no relevance to the overall policy making thrust. I commend what our report says to Government. I hope that they will be able to take on board what is said and ensure that they use it to guide their policy formation, whatever vicissitudes there may be about exactly how we will get there.


    Julie Elliott (Sunderland Central) (Lab): As ever, it is a pleasure to serve under your chairmanship, Mr Betts. I congratulate the Energy and Climate Change Committee and its Chair, the hon. Member for South Suffolk (Mr Yeo), on the important work it does in this area and especially on the report we are debating. I have to say, not as a scientist—I am a social scientist—that I found this one of the most interesting and contentious debates I have witnessed in this place. The last debate I responded to in this Chamber from this Committee was on how the media report this subject and the clarity with which they report it. With the references to Japanese knotweed, surveyors, facts, not facts and plateaux, I would love to see how they report this debate, but I suspect that they will probably not bother.


    I will refer to some of the comments that the Chair of the Select Committee made, which I totally agree with. Positive things are going on and the world is at a turning point. The announcements in Beijing in the past few weeks were encouraging and showed that the USA and China are looking at this issue more seriously. Things have moved forward. As he said, an international carbon emissions pact is much more likely than at any previous point. The whole world needs to step up towards Paris next year, and we need to do everything we can in this place to get ready for that.


    I start by looking at where the report concludes. We can be more confident than ever that human activity is the driving force behind the warming of our planet, and that the dominant cause is greenhouse gases. For me, there is therefore no scientific basis for downgrading, diluting or delaying the UK’s ambition to reduce our greenhouse gas emissions.


    I welcome the clarity of the report’s conclusions. It is right that IPCC reports are placed under strict scrutiny, as they are at the core of the UK and global response to the threat of climate change. It was, of course, the conclusions of previous IPCC reports that underpinned the previous Labour Government’s Climate Change Act 2008, a world-leading piece of legislation with targets of 80% emissions reductions to be achieved through interim carbon budgets. The carbon budgets are crucial, and it would have been deeply damaging had this Government not fully implemented the fourth carbon budget, as was threatened just a few months ago. I welcome the fact that the Government have now assured us on that.


    Given the fundamental underpinning of the IPCC reports for the UK, it is important that they be analysed in terms of UK energy policy. My right hon. Friend the Member for Doncaster North (Edward Miliband)has rightly stated that climate change is the greatest global threat facing our generation, requiring leadership and resolve. Indeed, the Energy and Climate Change Committee’s report quotes the Prime Minister as saying that "manmade climate change is one of the most serious threats that this country and this world face".


    Yet the lofty rhetoric is not always matched by the actions of Government and certain Secretaries of State. As a rich country and a significant emitter of carbon, the UK can show global leadership abroad only if we take bold action at home. The UK has a vital role to play in international negotiations on climate change, but we cannot and will not be taken seriously as global leaders if we are not seen to be taking action at home.


    Labour has committed to setting a 2030 power sector decarbonisation target, which is crucial for stimulating the investment in clean energy that will boost capacity and drive down costs. Yet this Government have refused to set such a target, which is frankly incompatible with what the report sets out. Furthermore, when the UK Government threaten a moratorium for onshore wind or when the Minister states that solar farms are not particularly welcome, it damages not just our clean energy economy, but our credibility abroad.


    The IPCC report shows just how important it is that we rebuild the low-carbon consensus. Having listened to the debate, I think that seems an interesting prospect. Just five MPs voted against the Climate Change Act in 2008 yet debates on climate and clean energy can often be hijacked by those who do not view climate change as a threat. The science has not changed. Indeed, the Committee’s report demonstrates the rigorous, evidence-based work that has gone into the IPPC report.


    My hon. Friend the Member for Blackley and Broughton (Graham Stringer) said that politicians change, alter and manoeuvre how the science is reported. Politicians interpret and they do so as policy makers, not scientists. One scientist will never totally agree with another, just as one politician will never totally agree with another. The issue is about interpretation and there is a value judgment on the evidence that is presented, which will always be the case. The science has not changed. The IPCC has provided overwhelming and compelling scientific evidence that climate change is real, that it is caused by human activity and that it will have disastrous consequences if urgent action is not taken to cut our carbon emissions and invest in mitigation.


    I am grateful to the Energy and Climate Change Committee for its work in evaluating the IPCC report and setting out recommendations, and I urge the Government to ignore pressure from their Back Benches and to ensure that the UK is best placed to help secure a legally binding agreement in Paris next year.


    The Parliamentary Under-Secretary of State for Energy and Climate Change (Amber Rudd): I congratulate my hon. Friend the Member for South Suffolk (Mr Yeo) on securing this debate and thank the Select Committee on Energy and Climate Change for its report on the Intergovernmental Panel on Climate Change’s working group I report on the fiscal science basis of climate change. The Government welcome the Committee’s finding that it provides the best summary and guide of the prevailing scientific opinion on climate change currently available to policy makers.


    Mr Lilley: Where does the Minister get the word "guide" from? It is not in the title of the document.


    Dr Whitehead: It was announced as that.


    Amber Rudd: Whether in the title of the document or not, it is taken as a guide.


    Mr Lilley: It was taken as such by the hon. Member for Southampton, Test (Dr Whitehead), but the Minister should not believe every word he says.


    Amber Rudd: This interesting debate has considered the roles of scientists and politicians. Like the hon. Member for Sunderland Central (Julie Elliott), I am not a scientist, but I agree with the hon. Member for Southampton, Test (Dr Whitehead) that that does not—I hope—preclude us from making the right policy judgments as we go forward.


    The IPCC’s fifth assessment report provides an unparalleled assessment of the latest climate science. There is no comparable process in terms of scope, rigour, transparency or level of Government engagement. The IPCC does not generate new climate science; it assesses peer-reviewed scientific work from thousands of practising expert scientists from around the world. The working group I report was produced by 809 authors, who assessed more than 9,000 scientific papers. The UK is fortunate to have world-leading expertise in many areas of climate science, and I am proud to say that some 100 of the authors were from the UK. The draft report underwent two rounds of review, overseen by a team of 50 review editors, whose role is described in the IPCC’s procedures.


    It is true, as my right hon. Friend the Member for Hitchin and Harpenden (Mr Lilley) pointed out, that the IPCC for the first time moved away from providing a best estimate as it was felt that it was misleading to have a single figure for an uncertain quantity. The IPCC scientists’ increased confidence in their findings is based on the conclusions of the large amount of wide-ranging literature published since the fourth assessment report. As a result, we can be assured that the latest IPCC assessment represents a true consensus of climate science expert opinion from around the world.


    The hon. Member for Blackley and Broughton (Graham Stringer) spoke of his concerns about the IPCC. I reassure him that the four-day synthesis meeting to which he referred was not held in secret and that the Government consider IPCC plenary meetings to be sufficiently transparent already through the presence of a number of observer organisations and detailed daily reports. There are 62 non-governmental organisations that are approved observers, as well as several inter- governmental and UN observer organisations.


    The Government have considered the Committee’s findings and, as we set out in our official response, seek to take forward a number of recommendations. The Government also strongly support the Committee’s recommendations, which is why we published our vision for the new global deal to be agreed in Paris next year. Our Paris 2015 vision document highlights the strong business and NGO support for securing a global climate change agreement. My hon. Friend the Member for South Suffolk highlights the importance of reaching an agreement at Paris 2015 and I share his dedication and increased optimism, to which the hon. Member for Sunderland Central also referred, following the recent European deal and the good signs from China in the recently announced US-China deal. Following the IPCC’s report—this guide or summary—there is no doubt that we need to take action. I share the view of the hon. Member for Southampton, Test about Japanese knotweed that action is best taken early before the house collapses. He also wisely cautioned against conspiracy theories, which are sometimes prevalent in this area. In the UK, we are taking action, focusing on the long term and using the carbon budgets to ensure that we deliver on our commitments.


    As I conclude, may I point out that it was 25 years ago that a scientist and politician, Margaret Thatcher, who appreciated the need, became the first leader of any major nation to call for a global treaty on climate change? There can be no doubting this Government’s commitment. In September, the UN Secretary-General engaged world leaders at a climate summit in New York, where the UK was represented by the Prime Minister, the Secretary of State for Energy and Climate Change the right hon. Member for Kingston and Surbiton (Mr Davey), and me. We are leading from the front and we will hopefully be present next year at Paris 2015 to secure the international agreement that the vast majority of us want and that scientists support.


    Mr Charles Walker (in the Chair): Mr Yeo, would you like to say a few words in response, before moving seamlessly into the next debate?


    Mr Yeo: Thank you, Mr Walker, and welcome to the Chair. It will be a pleasure to serve under your chairmanship. I particularly wish to draw attention to the fact that I am correctly dressed.


    To reflect on this helpful and revealing debate, I should say that I am sorry that we have not attracted the interest of anyone who is not, as it were, under duress to attend for one reason or another. Nevertheless, I dare say that a few dedicated outsiders will read our proceedings.


    May I mention to my right hon. Friend the Member for Hitchin and Harpenden (Mr Lilley) that the IPCC was established in 1988, not in 1997 as he suggested? I find the notion of a giant conspiracy fascinating and in some ways rather hilarious. The idea that thousands of scientists and politicians are somehow colluding is difficult to regard as credible.


    I think that my right hon. Friend bases his view on omissions from the "Summary for Policymakers" of some of the contents of the full report. It is, however, a strange form of conspiracy if a few policy makers get together and say, "Okay, we’re going to publish thousands of pages of documents, papers and the conclusions of an endless amount of work around the world in their entirety, so anyone can look at them. But then we’re going to get together and, because we don’t want all this work to be actually read, understood or communicated outside, we’re going to publish a summary that does not reflect accurately what is in the main document." In my experience, that is not how most conspirators proceed.


    Mr Lilley: May I make it absolutely clear that my hon. Friend has invented the idea of a conspiracy? Neither the hon. Member for Blackley and Broughton (Graham Stringer) nor I have mentioned any conspiracy. All we have said is that the summary is a work of advocacy and, in common with most such works, it leaves out factors and bits of evidence that do not reinforce the case that it wants to get over. That is all.


    Mr Yeo: I am grateful to my right hon. Friend for his reassurance that he is not alleging that any conspiracy has taken place. I am sure that those people who mistakenly thought that that was what he said will now stand duly abashed.


    I believe that the IPCC process is an extraordinarily open one. It could hardly go to greater lengths to ensure that every bit of evidence is available for public scrutiny and that every conclusion has been examined, re-examined and peer reviewed almost endlessly. For the avoidance of doubt, I should say that my conclusions about the IPCC process—and, I believe, my Committee’s conclusions about the fifth assessment report—are based on our careful consideration of the actual report in its entirety. We have not relied for any of our conclusions on a mere scrutiny of the "Summary for Policymakers". That is all I need to say about that debate, so I will move seamlessly on to our second debate.