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IPCC errors: facts and spin

Filed under: — group @ 14 February 2010 - (Czech) (Svenska)

Currently, a few errors –and supposed errors– in the last IPCC report (“AR4″) are making the media rounds – together with a lot of distortion and professional spin by parties interested in discrediting climate science.  Time for us to sort the wheat from the chaff: which of these putative errors are real, and which not? And what does it all mean, for the IPCC in particular, and for climate science more broadly?

Let’s start with a few basic facts about the IPCC.  The IPCC is not, as many people seem to think, a large organization. In fact, it has only 10 full-time staff in its secretariat at the World Meteorological Organization in Geneva, plus a few staff in four technical support units that help the chairs of the three IPCC working groups and the national greenhouse gas inventories group. The actual work of the IPCC is done by unpaid volunteers – thousands of scientists at universities and research institutes around the world who contribute as authors or reviewers to the completion of the IPCC reports. A large fraction of the relevant scientific community is thus involved in the effort.  The three working groups are:

Working Group 1 (WG1), which deals with the physical climate science basis, as assessed by the climatologists, including several of the Realclimate authors.

Working Group 2 (WG2), which deals with impacts of climate change on society and ecosystems, as assessed by social scientists, ecologists, etc.

Working Group 3 (WG3) , which deals with mitigation options for limiting global warming, as assessed by energy experts, economists, etc.

Assessment reports are published every six or seven years and writing them takes about three years. Each working group publishes one of the three volumes of each assessment. The focus of the recent allegations is the Fourth Assessment Report (AR4), which was published in 2007.  Its three volumes are almost a thousand pages each, in small print. They were written by over 450 lead authors and 800 contributing authors; most were not previous IPCC authors. There are three stages of review involving more than 2,500 expert reviewers who collectively submitted 90,000 review comments on the drafts. These, together with the authors’ responses to them, are all in the public record (see here and here for WG1 and WG2 respectively).

Errors in the IPCC Fourth Assessment Report (AR4)

As far as we’re aware, so far only one–or at most two–legitimate errors have been found in the AR4:

Himalayan glaciers: In a regional chapter on Asia in Volume 2, written by authors from the region, it was erroneously stated that 80% of Himalayan glacier area would very likely be gone by 2035. This is of course not the proper IPCC projection of future glacier decline, which is found in Volume 1 of the report. There we find a 45-page, perfectly valid chapter on glaciers, snow and ice (Chapter 4), with the authors including leading glacier experts (such as our colleague Georg Kaser from Austria, who first discovered the Himalaya error in the WG2 report).  There are also several pages on future glacier decline in Chapter 10 (“Global Climate Projections”), where the proper projections are used e.g. to estimate future sea level rise. So the problem here is not that the IPCC’s glacier experts made an incorrect prediction. The problem is that a WG2 chapter, instead of relying on the proper IPCC projections from their WG1 colleagues, cited an unreliable outside source in one place. Fixing this error involves deleting two sentences on page 493 of the WG2 report.

Sea level in the Netherlands: The WG2 report states that “The Netherlands is an example of a country highly susceptible to both sea-level rise and river flooding because 55% of its territory is below sea level”. This sentence was provided by a Dutch government agency – the Netherlands Environmental Assessment Agency, which has now published a correction stating that the sentence should have read “55 per cent of the Netherlands is at risk of flooding; 26 per cent of the country is below sea level, and 29 per cent is susceptible to river flooding”. It surely will go down as one of the more ironic episodes in its history when the Dutch parliament last Monday derided the IPCC, in a heated debate, for printing information provided by … the Dutch government. In addition, the IPCC notes that there are several definitions of the area below sea level. The Dutch Ministry of Transport uses the figure 60% (below high water level during storms), while others use 30% (below mean sea level). Needless to say, the actual number mentioned in the report has no bearing on any IPCC conclusions and has nothing to do with climate science, and it is questionable whether it should even be counted as an IPCC error.

Some other issues

African crop yields: The IPCC Synthesis Report states: “By 2020, in some countries, yields from rain-fed agriculture could be reduced by up to 50%.” This is properly referenced back to chapter 9.4 of WG2, which says: “In other countries, additional risks that could be exacerbated by climate change include greater erosion, deficiencies in yields from rain-fed agriculture of up to 50% during the 2000-2020 period, and reductions in crop growth period (Agoumi, 2003).”  The Agoumi reference is correct and reported correctly. The Sunday Times, in an article by Jonathan Leake, labels this issue “Africagate” – the main criticism being that Agoumi (2003) is not a peer-reviewed study (see below for our comments on “gray” literature), but a report from the International Institute for Sustainable Development and the Climate Change Knowledge Network, funded by the US Agency for International Development. The report, written by Morroccan climate expert Professor Ali Agoumi, is a summary of technical studies and research conducted to inform Initial National Communications from three countries (Morocco, Algeria and Tunisia) to the United Nations Framework Convention on Climate Change, and is a perfectly legitimate IPCC reference.

It is noteworthy that chapter 9.4 continues with “However, there is the possibility that adaptation could reduce these negative effects (Benhin, 2006).”  Some examples thereof follow, and then it states: “However, not all changes in climate and climate variability will be negative, as agriculture and the growing seasons in certain areas (for example, parts of the Ethiopian highlands and parts of southern Africa such as Mozambique), may lengthen under climate change, due to a combination of increased temperature and rainfall changes (Thornton et al., 2006). Mild climate scenarios project further benefits across African croplands for irrigated and, especially, dryland farms.” (Incidentally, the Benhin and Thornton references are also “gray”, but nobody has complained about them. Could there be double standards amongst the IPCC’s critics?)

Chapter 9.4 to us sounds like a balanced discussion of potential risks and benefits, based on the evidence available at the time–hardly the stuff for shrill “Africagate!” cries. If the IPCC can be criticized here, it is that in condensing these results for its Synthesis Report, important nuance and qualification were lost – especially the point that the risk of drought (defined as a 50% downturn in rainfall) “could be exacerbated by climate change”, as chapter 9.4 wrote – rather than being outright caused by climate change.

Trends in disaster losses: Jonathan Leake (again) in The Sunday Times accused the IPCC of wrongly linking global warming to natural disasters. The IPCC in a statement points out errors in Leake’s “misleading and baseless story”, and maintains that the IPCC provided “a balanced treatment of a complicated and important issue”. While we agree with the IPCC here, WG2 did include a debatable graph provided by Robert Muir-Wood (although not in the main report but only as Supplementary Material). It cited a paper by Muir-Wood as its source although that paper doesn’t include the graph, only the analysis that it is based on. Muir-Wood himself has gone on record to say that the IPCC has fairly represented his research findings and that it was appropriate to include them in the report. In our view there is no IPCC error here; at best there is a difference of opinion. Obviously, not every scientist will always agree with assessments made by the IPCC author teams.

Amazon forest dieback: Leake (yet again), with “research” by skeptic Richard North, has also promoted “Amazongate” with a story regarding a WG2 statement on the future of Amazonian forests under a drying climate.  The contested IPCC statement reads: “Up to 40% of the Amazonian forests could react drastically to even a slight reduction in precipitation; this means that the tropical vegetation, hydrology and climate system in South America could change very rapidly to another steady state, not necessarily producing gradual changes between the current and the future situation (Rowell and Moore, 2000).”  Leake’s problem is with the Rowell and Moore reference, a WWF report.

The roots of the story are in two blog pieces by North, in which he first claims that the IPCC assertions attributed to the WWF report are not actually in that report. Since this claim was immediately shown to be false,  North then argued that the WWF report’s basis for their statement (a 1999 Nature article by Nepstad et al.) dealt only with the effects of logging and fire –not drought– on Amazonian forests. To these various claims Nepstad has now responded, noting that the IPCC statement is in fact correct. The only issue is that the IPCC cited the WWF report rather than the underlying peer-reviewed papers by Nepstad et al. These studies actually provide the  basis for the IPCC’s estimate on Amazonian sensitivity to drought. Investigations of the correspondence between Leake, scientists, and a BBC reporter (see here and here and here) show that Leake ignored or misrepresented explanatory information given to him by Nepstad and another expert, Simon Lewis, and published his incorrect story anyway. This “issue” is thus completely without merit.

Gray literature: The IPCC cites 18,000 references in the AR4; the vast majority of these are peer-reviewed scientific journal papers. The IPCC maintains a clear guideline on the responsible use of so-called “gray” literature, which are typically reports by other organizations or governments. Especially for Working Groups 2 and 3 (but in some cases also for 1) it is indispensable to use gray sources, since many valuable data are published in them: reports by government statistics offices, the International Energy Agency, World Bank, UNEP and so on. This is particularly true when it comes to regional impacts in the least developed countries, where knowledgeable local experts exist who have little chance, or impetus, to publish in international science journals.

Reports by non-governmental organizations like the WWF can be used (as in the Himalaya glacier and Amazon forest cases) but any information from them needs to be carefully checked (this guideline was not followed in the former case). After all, the role of the IPCC is to assess information, not just compile anything it finds.  Assessment involves a level of critical judgment, double-checking, weighing supporting and conflicting pieces of evidence, and a critical appreciation of the methodology used to obtain the results. That is why leading researchers need to write the assessment reports – rather than say, hiring graduate students to compile a comprehensive literature review.

Media distortions

To those familiar with the science and the IPCC’s work, the current media discussion is in large part simply absurd and surreal. Journalists who have never even peeked into the IPCC report are now outraged that one wrong number appears on page 493 of Volume 2. We’ve met TV teams coming to film a report on the IPCC reports’ errors, who were astonished when they held one of the heavy volumes in hand, having never even seen it. They told us frankly that they had no way to make their own judgment; they could only report what they were being told about it. And there are well-organized lobby forces with proper PR skills that make sure these journalists are being told the “right” story. That explains why some media stories about what is supposedly said in the IPCC reports can easily be falsified simply by opening the report and reading. Unfortunately, as a broad-based volunteer effort with only minimal organizational structure the IPCC is not in a good position to rapidly counter misinformation.

One near-universal meme of the media stories on the Himalaya mistake was that this was “one of the most central predictions of the IPCC” – apparently in order to make the error look more serious than it was.  However, this prediction does not appear in any of the IPCC Summaries for Policy Makers, nor in the Synthesis Report (which at least partly explains why it went unnoticed for years). None of the media reports that we saw properly explained that Volume 1 (which is where projections of physical climate changes belong) has an extensive and entirely valid discussion of glacier loss.

What apparently has happened is that interested quarters, after the Himalyan glacier story broke, have sifted through the IPCC volumes with a fine-toothed comb, hoping to find more embarrassing errors. They have actually found precious little, but the little they did find was promptly hyped into Seagate, Africagate, Amazongate and so on. This has some similarity to the CRU email theft, where precious little was discovered from among thousands of emails, but a few sentences were plucked out of context, deliberately misinterpreted (like “hide the decline”) and then hyped into “Climategate”.

As lucidly analysed by Tim Holmes, there appear to be a few active leaders of this misinformation parade in the media. Jonathan Leake is carrying the ball on this, but his stories contain multiple errors, misrepresentations and misquotes. There also is a sizeable contingent of me-too journalism that is simply repeating the stories but not taking the time to form a well-founded view on the topics. Typically they report on various “allegations”, such as these  against the IPCC, similar to reporting that the CRU email hack lead to “allegations of data manipulation”. Technically it isn’t even wrong that there were such allegations. But isn’t it the responsibility of the media to actually investigate whether allegations have any merit before they decide to repeat them?

Leake incidentally attacked the scientific work of one of us (Stefan) in a Sunday Times article in January. This article was rather biased and contained some factual errors that Stefan asked to be corrected. He has received no response, nor was any correction made. Two British scientists quoted by Leake – Jonathan Gregory and Simon Holgate – independently wrote to Stefan after the article appeared to say they had been badly misquoted. One of them wrote that the experience with Leake had made him “reluctant to speak to any journalist about any subject at all”.

Does the IPCC need to change?

The IPCC has done a very good job so far, but certainly there is room for improvement. The review procedures could be organized better, for example. Until now, anyone has been allowed to review any part of the IPCC drafts they liked, but there was no coordination in the sense that say, a glacier expert was specifically assigned to double-check parts of the WG2 chapter on Asia. Such a practice would likely have caught the Himalayan glacier mistake. Another problem has been that reports of all three working groups had to be completed nearly at the same time, making it hard for WG2 to properly base their discussions on the conclusions and projections from WG1. This has already been improved on for the AR5, for which the WG2 report can be completed six months after the WG1 report.

Also, these errors revealed that the IPCC had no mechanism to publish errata. Since a few errors will inevitably turn up in a 2800-page report, obviously an avenue is needed to publish errata as soon as errors are identified.

Is climate science sound?

In some media reports the impression has been given that even the fundamental results of climate change science are now in question, such as whether humans are in fact changing the climate, causing glacier melt, sea level rise and so on. The IPCC does not carry out primary research, and hence any mistakes in the IPCC reports do not imply that any climate research itself is wrong. A reference to a poor report or an editorial lapse by IPCC authors obviously does not undermine climate science. Doubting basic results of climate science based on the recent claims against the IPCC is particularly ironic since none of the real or supposed errors being discussed are even in the Working Group 1 report, where the climate science basis is laid out.

To be fair to our colleagues from WG2 and WG3, climate scientists do have a much simpler task. The system we study is ruled by the well-known laws of physics, there is plenty of hard data and peer-reviewed studies, and the science is relatively mature. The greenhouse effect was discovered in 1824 by Fourier, the heat trapping properties of CO2 and other gases were first measured by Tyndall in 1859, the climate sensitivity to CO2 was first computed in 1896 by Arrhenius, and by the 1950s the scientific foundations were pretty much understood.

Do the above issues suggest “politicized science”, deliberate deceptions or a tendency towards alarmism on the part of IPCC? We do not think there is any factual basis for such allegations. To the contrary, large groups of (inherently cautious) scientists attempting to reach a consensus in a societally important collaborative document is a prescription for reaching generally “conservative” conclusions. And indeed, before the recent media flash broke out, the real discussion amongst experts was about the AR4 having underestimated, not exaggerated, certain aspects of climate change. These include such important topics as sea level rise and sea ice decline (see the sea ice and sea level chapters of the Copenhagen Diagnosis), where the data show that things are changing faster than the IPCC expected.

Overall then, the IPCC assessment reports reflect the state of scientific knowledge very well. There have been a few isolated errors, and these have been acknowledged and corrected. What is seriously amiss is something else: the public perception of the IPCC, and of climate science in general, has been massively distorted by the recent media storm. All of these various “gates” – Climategate, Amazongate, Seagate, Africagate, etc., do not represent scandals of the IPCC or of climate science. Rather, they are the embarrassing battle-cries of a media scandal, in which a few journalists have misled the public with grossly overblown or entirely fabricated pseudogates, and many others have naively and willingly followed along without seeing through the scam. It is not up to us as climate scientists to clear up this mess – it is up to the media world itself to put this right again, e.g. by publishing proper analysis pieces like the one of Tim Holmes and by issuing formal corrections of their mistaken reporting. We will follow with great interest whether the media world has the professional and moral integrity to correct its own errors.

PS. A new book by Realclimate-authors David Archer and Stefan Rahmstorf critically discussing the main findings of the AR4 (all three volumes) is just out: The Climate Crisis. None of the real or alleged errors are in this book, since none of those contentious statements plucked from the thousands of pages appeared to be “main findings” that needed to be discussed in a 250-page summary.

PPS. Same thing for Mike’s book Dire Predictions: Understanding Global Warming, which bills itself as “The illustrated guide to the findings of the IPCC”. Or Gavin’s “Climate Change: Picturing the Science” – which does include a few pictures of disappearing glaciers though!

Update 24 March: Simon Lewis has made an official complaint to the Press Complaints Commission about Leake’s Amazon story.

Update 29 March: IPCC Chairman Rajendra Pachauri has published an interesting article in the Guardian.

601 Responses to “IPCC errors: facts and spin”

  1. 101
    HotRod says:

    Not a science point, but I can’t take seriously attacks on journalism standards.

    a) no-one expects perfection of reporting, or anything close to it

    b) for the last x years almost all (UK) mainstream media have wholly uncritically parroted and exaggerated the ‘consensus’ view on AGW and CC.

    When they do this they pick on soundbites like the end of glaciers, polar bears, rainforest and Tuvalu. So when they turn, they do the same thing. Grow up, I’d say.

    Gavin – I agree with some of your replies criticising comments such as the BBC Pension Fund nonsense, and arguing against money/conspiracy theory. I don’t know whether you have done this in the past, but many on ‘your’ side have been very quick to suggest fossil fuel funding of sceptics etc. Maybe that’s not the same thing?

  2. 102
    Completely Fed Up says:

    Ray #48: you’ll notice that Pielke’s also doing the same.

  3. 103
    MikeFox says:

    Hi Galvin,
    Regarding response to 39. Lets hope for the success of predicted, measured, verified AGW caused by CO2. At least then we can say man controls nature, and controlled GW can be a thing of prosperity. If we have AGC or just GC we are all SOL.

  4. 104
    Bob Ward says:

    Roger Pielke Jr (#17) has neglected to reveal the full facts about the Muir-Wood, Miller and Boissonnade (2006) paper. The final sentence of the abstract to the paper states: “What is presented here provides a short summary of the global results of this study. Full results are in course of publication also covering individual peril regions and the exploration of correlations with global temperatures”.

    The full peer-reviewed paper was eventually published by Miller, Muir-Wood and Boissonnade in 2008 in the volume ‘Climate Extremes and Society’:

    This paper does not include the graph included in the Supplementary Materials to Chapter 1 of IPCC volume 2, but it does describe the analysis upon which it is based:

    “We caution that our model does not capture the possibility that there are no underlying factors that are common to years of high (low) temperature variation that would cause us to falsely attribute the trend in disaster losses to climatic reasons. Results suggest that the temperature anomaly is highly significant (at 1%) for normalized losses (r2=0.22) irrespective of the survey period (Table 12.A2 in the Appendix). Results for Australia, the Philippines, and India are again significant (at the same levels as in the first model) with a negative coefficient. The rise is equivalent to an increase in normalized catastrophe losses of US$4.8 billion (post-1950) and US$6.6 billion (post-1970) for each 0.1˚C rise in global temperatures. For details, please refer to table 12.1A in the Appendix. However, these results are highly dependent upon recent US hurricane losses during 2004 and 2005. When the regression is rerun without these losses, the results are no longer statistically significant (Table 12.2).”

    As Roger indicated, Robert Muir-Wood stated at an event in London on 5 February that he produced the graph used in the Supplementary materials section, so it would be surprising if it was not an accurate reflection of his work. Robert also said that he does not think the graph should have been used, although it is not clear why he supplied the graph in the first place if it was not for publication.

  5. 105
    Bob Ward says:

    Oh, and before Roger Pielke Jr complains about my previous post, the Miller et al. (2008) paper provides two summary sentences about its conclusions.

    In the ‘Abstract’, it states “We find insufficient evidence to claim a statistical relationship between global temperature increase and normalized catastrophe losses.”

    In the ‘Conclusions’, it states: “In sum, we found limited statistical evidence of an upward trend in normalized losses from 1970 through 2005 and insufficient evidence to claim a firm link between global warming and disaster losses.”

  6. 106
    Brian Carter says:

    With regard to mis-reporting by British newspapers such as the Mail, surely there are grounds for referring their uncorrected errors to the Press Complaints Commission, who are in a position to force them to issue apologies and corrections?

  7. 107
    Theo Hopkins says:

    @ Global Sceptic

    “@Gavin and Theo Hopkins

    Your logic is scant, and your personal attacks are not necessary.

    It is duly noted that you have no relevant response to my questions regarding the BBC’s pension.

    Perhaps then we need to discuss Pachauri’s ties to numerous for profit endeavors that directly rely on the success of AGW?

    Again, I’m curious as to your responses about these matters.


    You are posting tripe.

    However, BAe (British Aerospace) has just been fined in excess of £300,000,000 for bribery in selling military aircraft to Saudi Arabia.

    But that dosn’t mean their planes won’t fly.

  8. 108
    Completely Fed Up says:

    Or, in other words, they’ve taken the result:

    There is a warming trend but it’s not statistically significant

    And ignore the “warming trend” bit and concentrate on the “not statisically significant”, canting it as “no trend”.

    Compare and contrast with when they try to take 1998 and 2008 and show “a cooling trend” which is not statistically significant (nor, in this case, a cooling trend), and ignored the “not significant” bit (and, indeed the “not actually a trend” bit) and said that it was cooling, ‘cos, like, 1998 was, like warmer than 2008, yeah?

    Funnily enough, the lack of statistical significance here didn’t mean “no cooling trend”.

  9. 109


    Try here:

    Clement, A.C., Burgman R., and J.R. Norris 2009. “Observational and Model Evidence for Positive Low-Level Cloud Feedback.” Science 325, 460-464.

  10. 110
    Andreas Bjurström says:

    The arrogant scientific attitude of the IPCC, i.e. the recurrent claim that science is objective and the assessment free of errors, are the fundamental cause of the present debate. If the IPCC had been more humble, the sceptics spinn based on a sigle error would not be possible. Read the IPCC official statements from january 2010, also there the principal focus is on arrogance. Pachauri argued recently in an indian newspaper, that the acknowledgement of one error proves that the IPCC has an open scientific attitude. NO, it does not, since it took very intensive pressure over a rather long time period before Pachauri was forced to admit the error.

  11. 111

    [...] links a week after I wrote this piece, but providing good background information. The first is Real Climate with some background information on the IPCC itself and the various errors that have be…. The second is a look at the principal journalists behind this spate of alarmist articles about [...]

  12. 112

    Les Johnson: No statistically significant warming since 1995. According to Phil Jones.

    BPL: Read my lips: To detect a climate trend takes THIRTY YEARS OF DATA. How many years is 1995-2009? The numerical answer is left as an exercise for the student.

  13. 113
    Theo Hopkins says:

    I think you climate scientists should look at this recent survey by the BBC, in the UK which compares attitudes to climate change, pre “climategate” and now. (It looks grim). Things have rapidly changed in three months.


    What is important here is the various different attitudes to CC; it is not a monolithic body of doubt.

    Roughly the BBC poll says….

    1. AGW is happening.

    Then 41%
    Now 26%

    2. Warming is happening, but it is not due to human influence.

    Then 32%
    Now 38%

    3. It is “environmentalist propaganda” (propaganda is the word the BBC survey uses!)

    Then 8%
    Now 10%

    4. It is not happening

    Then 15%
    Now 25%


    OK? Now….

    Consider Group 3 to start with. (Environmentalist propaganda)

    Probably you would be wasting you time with this bunch. Interestingly, though, this is the bunch that has changed least in %age points. I assume that “Obama is a communist” types live here, as well.

    Consider Group 4. (It’s not happening)

    There has been a dramatic shift here. Your first step with this group is to move some of them back to accepting warming – but at a first stage, you need to move the back either into Group 1 _or_ Group 2. Don’t push people too hard at this point. :-)

    Consider Group 2. CC is happening, but it is not man-made.

    This may be the most difficult group to shift (IMHO), but the group that is most important to change. See my comments about ”judgment between competing ideas” further down the page.

    Consider Group 1.

    Give them a medal. But notice the massive shift in three months.

    Your main task is to get those that deserted AWG, probably mostly found in Group 2, back into the fold of AGW. How do you do that?

    I talk of “judgment between competing ideas”.

    Most of us can understand (without the maths) the analogy that is the greenhouse effect.

    Most of us can understand a “plausible” alternative such as solar variance/sun spots or whatever (without the maths).

    This below is now is my core point…

    However, what most people are not able to do is to make a _skilled and balanced judgment_ between the greenhouses and (say) solar change. Our (junior school) maths and our (secondary school) science is just not up to it. (And I am one such person). You have to, somehow, show the difference between two plausible different explanations – not just putting forward your own idea, and saying it is the best.

  14. 114
    Completely Fed Up says:

    Brian, two problems

    1) As Fox proved in court, there’s no requirement for “news” reporting to tell the truth.

    2) Any retraction will be printed in 5pt font just after the obituaries and will NEVER be mentioned by anyone who uses their errored statement to “prove” AGW is wrong.

    What happens instead is that in some cases another newspaper approaches a pertinent scientist who will tell them the correct statement.

  15. 115
    Completely Fed Up says:

    HotRod says:
    15 February 2010 at 4:29 AM

    Not a science point, but I can’t take seriously attacks on journalism standards.

    a) no-one expects perfection of reporting, or anything close to it”

    Well, not any more. It didn’t used to be that way.

    It’s all punditry now.

    The 60′s were the heyday of journalism, where investigating reporters reported AFTER investigating.

    Now it’s a lot easier to investigate quotes that you can print up to keep the editor happy.

  16. 116
    Completely Fed Up says:

    PS “b) for the last x years almost all (UK) mainstream media have wholly uncritically parroted and exaggerated the ‘consensus’ view on AGW and CC.”

    Citation needed.

    Fox news?

    The Sun?

    The Daily Mail?

  17. 117
    Harry Hodge says:


    As a non-scientist I have been sceptical with respect to AGW almost entirely on the basis there was a “consensus” – a function of of being a cynical old s** that that instintively disbelieves – or questions – anything that is “settled” – particularly when I am immediately labelled with the “denier” or “flatearther” tags. And when any dissenting voice is silenced and/or ridiculed. Free speech and free society and all that. Even “loonies” like me deserve to be allowed to speak – even if we are not to be listened to.

    The main reason for my scepticism was a basic, flat out, disbelief of the Hockey Stick graph. This graph is the very foundation stone of alarmist case – and if it is/was a fair representtion of events then “alarmism” would be justified.

    To accept the Hockey Stick requires the MWP and LIA to not have happened.

    So that is my starting point – so that you know I am not trolling.

    Now, based upon his recent Q & A, even Phil Jones accepts that there may be a case for the MWP (not withstanding the fact that human and livestok remains are being chipped out of the permafrost in Greenland as we speak. These remains can surely only suggest that it was a damn sight warmer in the past than it is now!)

    I do not need to be a scientist or have a degree in any climate based discipline to work this out. I don’t need tree rings and climate models – just logic!

    Do your contributers continue to believe that the Hockey Stick is a fair reprentation of temperatures over the years and that we are experiencing unprecedented increases in temperatures and uprecedented temperatures per se?

    Whatever way you read it, you just have to accept that Phil Jones now accepts that there may have been periods (in the recent past) where the planet has experienced warmer temperatures and there may have been periods of similar rises in temperature (where AGW could not be a contributing factor).

    This makes Phil Jones a “denier” – just like me. He is saying that the science isn’t “settled” and that, by implication, the Hockey Stick is suspect/wrong.

    If the Hockey Stick is wrong then the the foundation stone is removed and the whole AGW alarmism comes crashing down.

    As I read the comments above and other threads, I want to ask you guys, do you believe the Hockey Stick graph is a true and fair representation of the historical temperatue record for planet earth?

    [Response: Nothing you say is recognizable as anything that has actually been claimed by the scientists invovled. Do some searches on this site for 'unsettled' science, the uncertainties in paleo reconstructions, what the implications are for different readings of the records. Your impression that the hockey stick was some central tenet of anything is a distortion that has been heavily promoted by people trying to confuse the public. Nothing jones said is out of line with what any of us have said on the topic. -gavin]

  18. 118
    Göran Rudling says:

    You guys don’t seem to understand. And I assume it has to do with that you don’t want to understand. This story is not about “getting some facts wrong”. It is about creating bogus scare stories in order to influence policy makers to make decisions. Scare tactics.

    In the WGII report a large section is about fresh water supplies in the future. IPCC made up the scenario that the Himalaya’s would melt rapidly threatening the future supply of fresh water for half a billion people. In order to make the scare bigger it is stated that 400 000 km2 ice out of a total 500 000 km2 glacier ice would melt in 30 years. Not only creating long term drought but disaster near term because of flooding.

    The errors regarding crop yields in Africa is that IPCC, by using false information, is implying that famine is coming due to warming.

    The Amazon error is about that the rain forest is in really serious danger.

    The disaster error is about that we as humans will face enormous costs due to disasters caused by global warming.

    IPCC made all these impacts up after inventing facts in order to make global warming a real threat.

    It is obvious that the so called “facts” originate from gray literature. The IPCC may use gray literature (mostly in the WGIII) regarding
    “information about the experience and practice of the private sector in mitigation and adaptation activities” since information is often “found in sources that have not been published or peer-reviewed (e.g., industry journals, internal organisational publications, non-peer reviewed reports or working papers of research institutions, proceedings of workshops etc)”

    If the IPCC is using gray literature in reports it must follow the rules. “Non-peer-reviewed sources will be listed in the reference sections of IPCC Reports. These will be integrated with references for the peer-reviewed sources. These will be integrated with references to the peer reviewed sources stating how the material can be accessed, but will be followed by a statement that they are not published.”

    It is evident that the IPCC invented facts are not about information about the private sector. It is also evident that the sources are not listed properly.

    Your defense of the IPCC saying nothing is seriously wrong isn’t good enough. Not if you imply that you are about Real Climate. Your take on the IPCC scandal is more befitting a blog with the name Invented Climate.

  19. 119

    For those who want statistically significant warming in 10 years, look at HadCrut3 and do a regression on 1878 to 1887, a 10-year period. Over that time, cooling was (wait for it) 2.9 degrees per century, with correlation coefficient 0.75. Exercise for the reader: is this statistically significant. Did the 19th century end with an ice age? Well, no. Conclusion: natural variability on this sort of timescale overwhelms the kind of relatively slow trend we’d expect from AGW.

  20. 120
    werecow says:

    Cheers for finally tackling this thing in full guys. It’s unfortunate that it had to take so long though; I get that you needed to be thorough, but I fear that the worst damage has already been done, and I’m not too optimistic about the media correcting itself on any of it. I actually live in Holland, and I’ve been cursing at the media for complete ineptitude for the past month or so. It’s astounding to me that the people who are supposed to inform us on topics like these are actually less informed on the subject than I am.

  21. 121
    SteveF says:

    @ Brian Carter:

    With regard to mis-reporting by British newspapers such as the Mail, surely there are grounds for referring their uncorrected errors to the Press Complaints Commission, who are in a position to force them to issue apologies and corrections?

    The PCC operates by policing a voluntary code of practice devised by a body called the Editor’s Code Committee. The chairman of the Editor’s Code Committee is Paul Dacre. Incidentally, the editor of the Daily Mail is one Paul Dacre.

  22. 122
    Chris Rhetts says:

    Am I the only one who noticed that in comment #21, Ray Ladbury specifically states he will offer “A couple of thoughts.”, but then proceeds to list (by my count) THREE thoughts? Should we be doing a little checking into “Couple-of-thoughts-gate”?

  23. 123
    HotRod says:

    Re 116: Completely Fed Up questions my: “b) for the last x years almost all (UK) mainstream media have wholly uncritically parroted and exaggerated the ‘consensus’ view on AGW and CC.”, requesting citations.

    Can’t be bothered to trawl back over 10 or 20 years of column inches and BBC/Channel 4 airtime and judge what percentage fit my criteria for uncritical parroting, but I’d have a stab at 90%+. Certainly a huge buyer at 80%.

    As I said, grow up. Post Climategate is the first time the (UK) MSM has turned on you after decades of unquestioning acceptance. Take it like a man. Go over the history of Harrabin (BBC) Leake (Times) and Pearce (Guardian) and see how many critical features they EVER did pre Climategate. The BBC in its official code of conduct eschewed any need for balance – I don’t say whether that’s right or wrong, it’s just the way it was, there and elsewhere.

  24. 124
    Dennis says:

    Mistakes happen. We all know this. The single most insulting aspect of the media hype around the ICPP report errors is that each and every journalist and wannabe journalist who mentions the IPCC errors has probably committed ten times as many errors in his own reporting over the past year and has failed to issue corrections. For any scientist out there who gets contacted by a reporter about mistakes — ask him to go through his work and fix his own before commenting on yours.

  25. 125
    B Buckner says:

    #95 Ray Ladbury:

    Tamino concludes this in the reference you provide:

    “Therefore we need at least 14 years of GISS data (from 1996 to the present) to draw a confident conclusion about the most recent trend. In fact, since we have additional unaccounted-for uncertainty (such as the parameter estimates for our ARMA(1,1) model), we actually need a bit more. Let’s say that less than 15 years of data allows no confident conclusion about whether the trend in GISS data is warming or cooling.”

    So it seems Phil Jones assertion actually has some significance, no?

    [Response: You are missing the point completely- short term trends are not significant. Depending on the record, you need 15 or 16 or 20 years or whatever to get a statistically sig trend. All of which are warming. I find it hilarious that the people who have been pushing global cooling memes based on even shorter time periods now think it's news that short term trends aren't significant. - gavin]

  26. 126
    George Robinson says:

    Not any mention of the glaciers nearer to home. I visit them in Norway twice a year, early spring, make photographic records, and then late autumn when the summer melting has all but finished. Each year the Briksdals glacier has since the mid 90s receded, in just one year by more than 135 meters, and now what is more alarming, is that these glaciers are also narrowing, some so narrow that one could spit across them, well almost. The main reason being is that winters are not as long as they used to be, so less snow on the upper snow plateaus, now perhaps only 15 to 20 meters instead of 25 to 30 meters before. So, the Josterdals glacier is indeed in big big trouble, and this is the biggest icefield on the European continent

  27. 127
    Harry Hodge says:

    Ref my 117 above (harry hodge) and Gavin’s response.

    Gavin, your response to my comment was:

    [Response: Nothing you say is recognizable as anything that has actually been claimed by the scientists invovled. Do some searches on this site for 'unsettled' science, the uncertainties in paleo reconstructions, what the implications are for different readings of the records. Your impression that the hockey stick was some central tenet of anything is a distortion that has been heavily promoted by people trying to confuse the public. Nothing jones said is out of line with what any of us have said on the topic. -gavin] END.

    As a non-scientist, I am subject to short form summaries and headlines. I do not have the education and knowledge to carry out, or evaluate, research myself. The Hockey Stick graph was put to me by Al Gore and the IPCC as part of the “killer” arguments for the AGW proposition.

    Your reasoned response to my original comment (and thank you for publishing my comment and your non-insulting response) highlights a problem. I have assumed that you guys accept the relevance and, for want of a better word “truth” of the representation that is the Hockey Stick. Are you saying that RealClimate doesn’t necessarily accept The Hockey Stick as the best representation of events and/or that there are (and I am trying to choose non-confrontational words) potential doubts about the science it represents? (i.e the science isn’t “settled”).

    If you are, then you have a potential convert. Using my (somewhat inadequate) brain power, I can accept the evidence that that the planet is slowly warming although I cannot know why this is. Similarly, I totally reject the Hockey Stick (based upon same limited brain power).

    To date though, I have been subjected to a Hockey Stick graph (that I reject for reasons indicated earlier) as the poster child for the “alarmist” viewpoint (as an aside, I am also subject to images of forlorn looking Polar bears and ice carving which we both know can only prove the existance of forlorn Polar Bears and ice carving – and does not prove anything one way or t’other. I am also given the Himalayan, Amazon, Hurricane and natural disaster headlines – which are then knocked down (apparently).

    When the Hockey Stick is publicly (again, I try to choose a non-confrontational word) stepped down from being “the truth, the settled science” and replaced with something that does represent the consensus then I will have the information to start again and reassess.

    Maybe Realclimate should put together a graph that does, somehow, represent the “best estimate” of global temperatures over the last few thousand years and then we reassess based upon that?

    [Response: The best estimate to date is probably that of Mann et al 2008, but it isn't that different to anything else you might have seen (ability to link is limited since I'm answering this from my phone). But the problem here has nothing to do with the science, or the caveats the scientists make, or the uncertainties in various proxy records, but rather how complex information get iconized and made into a sound bite and how people then take that simplified icon and assume that it is in itself proof of the complex theory from which it is derived. These leads to people thinking (erroneously) that medieval temperatures are somehow determinative of why climate is changing now. It is not likely that they were as high as they are today, but we can't absolutely rule it out, but this only matters if you think this is the basis of anything- since it isn't, it doesn't. Climate is complex and whenever someone tries to tell you it's based on one person, or one graph or one soundbite, beware! You can find out the truth, but it's not always easy. My book's a pretty good start though! :-) gavin]

    [Response: Here is a couple of links for you. Why the “hockey stick” doesn’t tell us anything about causes of warming (current warming could be anthropogenic even if it was warmer in the middle ages, and current warming could be completely natural even if unprecedented in the past millennia – to tell, you need to look at the forcing, i.e. the source of the heat).
    The Copenhagen Diagnosis showing a number of the most recent climate reconstructions in Fig. 19. (Warning: there’s a polar bear foto in it.)
    And of course IPCC in its chapter 6 shows an overview of all available temperature reconstructions for the past millennium by different research groups (that was dozen at that time).

  28. 128
    Trysail says:

    As far as snow depth goes, Washington D.C. recently broke their 1899 snow record of 54.4 inches and now has a new record of 54.9 inches. We are told that the new record is due to “extreme weather” caused by “global warming.” If so, what caused the nearly identical “extreme weather” over a century ago? Alarmists tell us that heavy snow used to be caused by cold, but now is caused by warmth. The 1899 record was set long before the hockey stick brought temperatures to “unprecedented levels.”

    Now lets take their poor logic one step further. Ice ages occur when the snow line moves very far south. If “most climate scientists” are claiming that global warming is causing the snow line to move south, then the logical corollary is that ice ages are caused by further warming temperatures. Clearly that is not true.

    Furthermore, Hansen correctly tells us that as the snow line moves south, the earth’s albedo increases causing further cooling.

    The sensible theory is that the snow line moves south when the climate is cold, and north when the climate is warm. And the record snow we are seeing this winter is due to cold, not warm temperatures.

  29. 129
    Ray Ladbury says:

    Goran Rudling claims the glacier error was an IPCC scare tactic:

    And how fricking clever of them to hide it in a chapter of a WG report and not mention it in the Summary or the Exec Summary. Please

    As to climate change causing serious problems for water in Asia-that is quite credible, just on a longer timescale than 25 years.

    The Amazon–likewise. It is certainly vulnerable to drought, and climate change is likely to exacerbate drought.

    Holland… Well, let’s just say, I wouldn’t want a long-term lease on beach front property there.

    African crop production–hey, I’ve lived there. I know there is a whole lot of land that is marginal for farming.

    In short, no we won’t see catastrophe in 25 years time. However, if we don’t act within 25 years time, catastrophe will become inevitable.

    I would suggest becoming familiar with what the science actually says so that you are vulnerable to neigher scare tactics nor reassuring lies.

  30. 130
    Completely Fed Up says:

    Göran Rudling says:
    15 February 2010 at 7:40 AM
    This story is not about “getting some facts wrong”. It is about creating bogus scare stories in order to influence policy makers to make decisions. Scare tactics.”

    Indeed it is.

    So when are Beck, Hannity, Inholfe et al going to stop scaring people with New World Order and Stone Age Regression and Poor Starving African scare stories to influende policy makers?

  31. 131
    Ray Ladbury says:

    Gilles says “The errors in IPCC are not technical.. They are psychological.”

    Horse puckey. The “errors” consist of a fricking typo–caught not by a denialist but by a climate scientist–and one questionable reference. The rest are not improper. Gilles, your problem is that you do not understand the process. The different working groups have very different charters.

    WG I must do a conservative analysis to show that the science is cogent. In this sense, conservative means including only those aspects that are agreed upon by the vast majority of experts and have a high probability of being correct.

    WG’s II and III are more of an engineering charter. A conservative analysis by WG II must establish an upper bound for consequences due to a particular threat. Note that I say UPPER bound. It need not be accurate, only finite. If it turns out to drive risk calculus, it can be improved and made tighter. The goal is to find out what the really serious threats are. It is still early days here. There aren’t many peer-reviewed journals for this subject. Ih will therefore have to use grey literature.

    WG III’s charter is different still–here “conservative” means demonstrably effective against a particular threat. It is very, very early days here. The only effective mechanisms we have at present are threat avoidance.

    Why not learn what the process is trying to do so that at least your criticisms are not based on utter ignorance?

  32. 132
    steve says:

    “climate scientists do have a much simpler task. The system we study is ruled by the well-known laws of physics, there is plenty of hard data and peer-reviewed studies…”

    It is statements like this at RC that infuriate me. No one is skeptical about the quantum theory of molecular spectroscopy.

    There is room for scientific skepticism about feedbacks, sensitivity, and ocean-atmosphere interactions.

    Hard data? Is there any other kind?


  33. 133
    Completely Fed Up says:

    “(It looks grim). Things have rapidly changed in three months.”

    And because climate gate has nothing behind it, another three months will see a change again.

    Most of the change in that 25% of “not happening” is because of the cold weather in the UK.

    OMG! Pwnies! It’s snowing!!!

    This is not indicative of what happens across the globe.

  34. 134
    Completely Fed Up says:

    Andreas Bjurström says:
    15 February 2010 at 6:41 AM

    The arrogant scientific attitude of the NIPCC”

    Corrected your spelling mistake there.

  35. 135
    Ray Ladbury says:

    Septic Matthew @78
    Huh? Matthew, that is utter crap! CO2 has been known to be a greenhouse gas since the 1850s, and anthropogenic climate change due to CO2 was first predicted in 1896! Good lord, where do you come up with this?!

    There are a dozen or so independent lines of evidence that all favor a CO2 sensitivity around 3 degrees per doubling–and preclude a sensitivity less than 2 degrees per doubling. Please, go read Weart’s Discovery of Global Warming. Straw men are not interesting.

  36. 136
    windansea says:

    Gavin sez: The ‘success’ of AGW? This chasing down the rabbit hole in search of imaginary reasons why anyone would actually want AGW to be true is simple delusion.

    Phil Jones: As you know, I’m not political. If anything, I would like to see the climate change happen, so the science could be proved right, regardless of the consequences. This isn’t being political, it is being selfish.



  37. 137
    Ray Ladbury says:

    M. Cejnar says, ““Errors” in reports tend to be random. Why is it that all errors, mistakes and omissions in IPCC always favours AGW alarmism?”

    Hmm, actually, they aren’t. The IPCC is clearly way too conservative in the way it treats the cryosphere.

    And given that “errors” in reports are random, why does M. Cejnar only pay attention to the ones that exacerbate concern over climate change?

  38. 138
    Ray Ladbury says:

    Peterr, When a person refuses to consider the evidence, what word other than “denialist” is appropriate. To call them a “skeptic” is to debase that word.

    I’d be more than happy to call Steve McI an auditor. I mean, after all, he’s spent a decade examining a single paper, which is now interesting only from the point of view of history of science. Meantime science has piled mountains of evidence around him.

    Peterr, I’d be more than happy to call you a skeptic if I could get you to just consider the evidence sufficiently to give me an alternative explanation of it that makes as much sense as the one implied by the current theory of Earth’s climate. I’ll await that with great anticipation.

  39. 139
    Andreas Bjurström says:

    @132 Completely Fed Up, i suggest that you contribute with something substantial or be quiet. There is far too much nonsense on all sides. For me, I am a climate believer, to please dont assume otherwise.

  40. 140
    Geoff Wexler says:

    Both Harrabin and the BBC poll have narrowed down their questions. The effect of this pre-occupation with the existence and cause of the recent global warming, which is of course important, is that it ends up with the public (including some scientists) thinking that it all started and perhaps ends with thermometers. Some others now have a dim awareness of a row over a hockey stick.

    What’s missing from both Harrabin’s questions and the BBC poll is any reference to the science, which came first. We are ultimately dependent on the effects of future levels of CO2 which may dwarf existing concentrations as well as other forcings. I suppose the BBC could not have asked a question about climate sensitivity because they and the rest of the media have not done a good job in informing the public about it. How many people will appreciate ?

    Here is a question.
    Suppose the MWP was much bigger and more global than generally thought. Why is so easy to persuade people that this would reduce estimates of future warming rather than the reverse?

  41. 141
    Ray Ladbury says:

    Trysail says of the recent DC snowfall: “We are told that the new record is due to “extreme weather” caused by “global warming.””

    Who the hell told you that? Not a scientist, surely? The current record snowfalls are due to the El Nino, which is sending warm moist air up the coast and a series of high-pressure fronts above the Capital area. In other words, it’s weather!

    Cut the crap and get serious!

  42. 142
    Ian Rae says:

    >This sentence was provided by a Dutch government agency

    An odd defence for an organization who claims to have “experts” who “review” its statements.

    The issue that you really need to address is why these errors that get missed by the review process tend to lean in one direction — that of alarmism. Chance or bias?

  43. 143
    Ray Ladbury says:

    You are missing the point, utterly. This is not about positive or negative press. This is about getting the science right. The press is failing utterly at that. That is the point.

    When the press attributed Katrina to climate change, RC and the posters here pointed out that while climate change could exacerbate hurricane strength, Katrina was a weather event.

    When the mistake in the Himmalayan glacier melting was discovered, people here acknowledged it for what it was–an inadvertent mistake.

    There is no desire here to defend the indefensible. What we’d like to see is journalists living up to the standards of their profession.

  44. 144
    Sou says:

    Wouldn’t it be great if the different governments who ‘contribute’ to the intergovernmental panel were to decide that climate change was an important enough issue to invest a bit more in the reporting of it. For example, to recruit a team of paid science writers and public relations people. I know we will always rely on the volunteer effort of scientists to write and review the material. What is need is a top quality public communication layer – not just for preparing the FAQs and other documents for ‘dummies’, but for dealing with the media and with the general public.

    It’s clear that most scientists have neither the time, skills nor training to take on the role of liaising with the media. And nor should they, except as guest experts from time to time. Their time and ongoing work is much too valuable in any case.

    If something isn’t done soon, the climate will catch most people before they know what’s happening. It’s not the responsibility of scientists to ‘spread the word’. That is the role of governments and frankly, they are letting societies down abominably in that regard.

    Governments have all agreed the problem is real, serious and urgent. Yet they dilly dally and allow media disinformation to run riot without lifting a finger.

    Have they no care or responsibility? I don’t know what political leaders think their role is if not leadership in time of crisis.

    The very fact that this site exists and is so necessary, is a sad reflection of the lack of leadership of all nations IMO.

    Gavin and his team are to be highly commended – but they shouldn’t have to do this. The world’s leaders should hang their heads in shame at what they are allowing to happen.

  45. 145
    Ron Taylor says:

    This is a great post, very helpful. It pulls together and clarifies all the little bits and pieces that have been drifting through the media. It could not be more obvious that a highly sophisticated disinformation campaign is underway.

  46. 146
    Ray Ladbury says:

    Chris Rhetts @122, The third point was a bonus. I was having a 3 for 2 sale last night!

  47. 147
    Sou says:

    @141 Ray Ladbury, ClimateProgress as I understand it is saying to the press that the heavy snowfalls are not inconsistent with climate change. The warmer temps can result in higher moisture content and heavier precipitation.

    Make of it what you will, but it makes sense to me.

  48. 148
    Ray Ladbury says:

    Ian Rae says, “An odd defence for an organization who claims to have “experts” who “review” its statements.”

    Uh, Ian, who ought to know better how much of their country is under Sea level than the Dutch Gov’t?

    Did you miss the point about the IPCC having limited staff? Well let me reiterate: The IPCC has limited staff. Got it, now?

  49. 149
    Ray Ladbury says:

    Steve says “There is room for scientific skepticism about feedbacks, sensitivity, and ocean-atmosphere interactions.”

    Great, where’s your climate model with sensitivity less than 2 degrees per doubling. Such a beast would be very interesting and no such model exists yet. If you can come up with one that actually looks like Earth, you’ll get on Oprah!

    And pray, how are you going to tackle a dozen different separate lines of evidence that all favor a sensitivity of 3 degrees per doubling and precude a sensitivity below 2. I look forward to your paper on why everyone else is wrong. Where will you be publishing? Science? Nature? Energy & Environment?

  50. 150
    Ray Ladbury says:

    Your estimate of CO2 sensitivity utterly neglects feedbacks. There are many analyses showing via at least a dozen independent lines of evidence that CO2 sensitivity is likely 3 degrees per doubling and cannot be below 2 degrees per doubling (95% CL).

    Go learn the real science. Then come back and we can tell why Schwartz is wrong.

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