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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. 151
    Ray Ladbury says:

    The war on science is as old as science. Whether it is the church or libertarians, there will always be people who resent being told what they don’t want to hear. The answer: Keep telling them and emphasizing the evidence. Eventually, all but the most blinkered will hear, and you really don’t want them on your side anyway.

  2. 152
    Ellis says:

    Come now isn’t all of the literature grey. Can’t we just fire up the models and see exactly where in time and space there will be droughts. Seems to me if we are to place any validity in the output of these models then they certainly should be able to pinpoint anomalous rainfall areas such as the Amazon or Africa or are the modelers speaking with two tongues in their models ability?
    Incidentally, are there any paleo recons of the average global temperature when the Sahel was last green?

  3. 153
    Harry Hodge says:

    Ref My 127 and Gavin’s response.

    I have now had a look at the graphs in Mann et al 2008. Question: how do I put together Mann’s graphs with Phil Jones’ answer in the Harrabin Q & A where he says something along the line of “there is no significant statistical evidence of warming since 1995 (or 98)? There would appear to be significant differnces between Mann’s graphs and Jones statement – or am I missing something?

  4. 154
    Bob says:

    Ruth tries to make a point in #113 which, I think, epitomizes the problem here. Scientists use very precise language (actually, they tend to use math, because no matter how hard you try, any spoken language is too imprecise for scientific purposes). Things mean very, very specific things, and you can’t hear what you want to hear, or miss the nuances, and understand what is being said.

    To Ruth’s post… she very erroneously finds two statements incompatible, because she doesn’t understand the differences in the two.

    She quoted the RC Glossary as saying (about the MWP):

    “…arguments that such evidence supports anomalous global warmth during this time period is based on faulty logic and/or misinterpretations of the available evidence.”

    She then quotes Jones on the same issue.

    “There is much debate over whether the Medieval Warm Period was global in extent or not. The MWP is most clearly expressed in parts of North America, the North Atlantic and Europe and parts of Asia. For it to be global in extent the MWP would need to be seen clearly in more records from the tropical regions and the Southern Hemisphere. There are very few palaeoclimatic records for these latter two regions.”

    To clarify the difference for Ruth:

    The RC Glossary is not talking about whether or not the MWP exists. It is stating that the thin and inadequate evidence for a global MWP representing anomalous warmth makes any arguments for its existence — based on the current, insufficient evidence — categorically wrong.

    This does not say that the MPW cannot be global. It says that current evidence does not support that argument. More evidence is needed to make the case.

    Jones, on the other hand, is saying that the case could be made some day — if someone would just find global evidence to support it by producing proxy studies of tropical and Southern Hemisphere temperatures during the period.

    There is nothing at all incompatible in these two positions. The first says you can’t argue the point using the current evidence, the second says that it could be proven if someone found the proper evidence. There is no inconsistency in the mere facts that the first does not bother to explicitly state that the MWP could be global (and anomalous), and that the second does not bother to explicitly state that until a stronger case is made, the argument cannot be used in the debate.

    And this is part of the problem. The layman not only is poorly trained in science, but they are also poorly trained in critical thinking and clarity in writing (and reading what is written).

    You can’t win with those people, because they are too easily mislead, either by their own confusion, or the lead of someone else who is confused.

  5. 155
    Didactylos says:

    J said:

    Please. He said it. The spin on this site is dizzying:

    “Do you agree that from 1995 to the present there has been no statistically-significant global warming?”

    Jones: “Yes, but only just.”

    The problem has nothing to do with Jones’ answer, which was perfectly correct. The problem is you fail to understand the question. You think it means “Do you agree that global warming has stopped since 1995?” – But that’s not what it says, and more importantly, that’s not what it means.

    And that’s your spin. In the question, not the answer.

    Jones makes it perfectly clear that despite the poorly worded question, there has been warming since 1995. But the spinmeisters always ignore that part of the answer, don’t they?

  6. 156
    John says:

    “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.”

    Like this you mean…..

    Phil Jones:

    “So, in answer to the question, the warming rates for all 4 periods are similar and not statistically significantly different from each other.”

    Here are the trends and significances for each period:
    Period Length Trend
    (Degrees C per decade) Significance
    1860-1880 21 0.163 Yes
    1910-1940 31 0.15 Yes
    1975-1998 24 0.166 Yes
    1975-2009 35 0.161 Yes

  7. 157
    Didactylos says:

    HotRod said: “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?”

    It’s not a case of “suggesting”. Sadly, it’s a case of researched and published fact. You will find the work of Oreskes very informative.

    Now why doesn’t this get the same publicity, and the same outrage, that these silly “gates” have enjoyed? Could it be because we simply don’t expect anything else from faceless corporations and amoral lobbyists?

  8. 158
    Didactylos says:

    Let me expand my point about how the Jones question was spun.

    It cleverly puts “warming” and “statistically significant” into the same question. No good scientist is likely to question this, since significance is a very important factor.

    But it’s phrased as a yes/no question. Lazy or ignorant readers will just skip the “statistically significant” and assume Jones just agreed that there was no global warming. More astute, but still uninformed readers will assume that “no statistically significant warming” means that the warming has been smaller than expected, and therefore isn’t significant.

    The reality is that the warming has been entirely within expectations, but 15 years is too short to make statements about “warming” or “not warming”. Actually, 15 years is marginal. But wait – Jones said that too!

    Scientists shouldn’t be expected to deal with deception like this. They deal with complicated issues, and communicating them is not easy. Shame on the BBC interviewer for failing to filter questions that are obviously designed to solicit a particular answer.

    Judging by the sheer number of people who have failed to understand question and answer, there is a real problem here.

  9. 159

    Ian Rae,

    Some examples of how the IPCC is not very likely exaggerating things, eg these underestimates of the speed of the problem:
    - From 2007-2009, there was about 40% less Arctic summer sea ice than the IPCC predicted, far exceeding its worst-case scenarios.
    - Recent global average sea-level rise is about 80% more than the IPCC predicted.
    - By 2100, global sea level is expected to rise at least twice as much as the IPCC predicted.
    - Global CO2 emissions are around the highest scenarios considered by the IPCC.

    And here (, part II) for why the lowest “scenario” in an IPCC figure is a wholly implausible “feel good” scenario.

  10. 160
    Ruth says:

    Thank you, Bob (15 February 2010 at 10:52 AM).

    So is Professor Jones saying that there is simply not enough Southern Hemisphere proxy data to support a global temperature reconstruction dating back over 1000 years? (and according to Gavin’s inline replies, that is no different to what other climate scientists have been saying?)

  11. 161
    EL says:

    “Does the IPCC need to change?”

    Obviously, the IPCC does need to change.

    “Glaciers in the Himalaya are receding faster than in any other part of the world (see Table 10.9) and, if the present rate continues, the likelihood of them disappearing by the year 2035 and perhaps sooner is very high if the Earth keeps warming at the current rate. Its total area will likely shrink from the present 500,000 to 100,000 km2 by the year 2035 (WWF, 2005).”

    Where in the following report does “500,000 to 100,000 km2″ occur?

    In fact, the report says:
    “The Himalayas have the largest concentration of glaciers outside the polar caps. With glacier coverage of 33,000 km2, the region is aptly called the “Water Tower of Asia” as it provides around 8.6 X 106 m3 of water annually (Dyurgerov and Maier, 1997).”

    The IPCC is going to have to improve its quality. So yes, it needs to change.

  12. 162
    John says:

    “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.”

    Oh come now, this site has screamed for years that the current warming is completely without parallel in human history, and the MWP has been disregarded as near fiction by most here. Now all of a sudden Jones breaks rank and now you are saying “not likely that they were as high”.

    Basically Gavin you do not have a clue if the MWP was a warm, locally or globally, yet are happy to dismiss it in with broad brush statements.

    People are not erroneously thinking it is determinative, just that maybe something comparable happened in human history, which flies in the face of the “unprecedented” warming message being rammed down our throats.

    The major point here is, if the temperature was anywhere close then its not unprecedented in human history, and could point to other factors that you have ignored, misinterpreted, or just are not aware of, being ignored because C02 has been pinned down as the baddie.

  13. 163
    Tom Dayton says:

    Harry Hodge, I believe what Gavin has been trying to get across to you is that you need a grounding in the basics before you can ask questions that are relevant. I don’t think anyone is blaming you for asking questions that are so far off base; you’ve been consuming information that has been manipulated by deniers and the media.

    If you want a free overview to get started (though Gavin’s book is excellent), I suggest cce’s The Global Warming Debate. (For other readers who wondered where that site went, cce just revived it at a new address.)

  14. 164
    John says:

    “My book’s a pretty good start though! :-) gavin]”

    Follow the money you mean Gavin?

  15. 165
    John 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”

    So Pachuari did not mention it in a speech pre-Copenhagen then? Please.

  16. 166
    John Peter says:

    #41 Jerry Steffens

    Thanks for the ref to Chap 8, it does help. I had looked in Chapter 2, but 8 looks much better for clouds.

    David B. Benson (42)

    I guess if clouds let the Eemian get away we shouldn’t count on them for our salvation.

    I got interested in Climate Change after reading some of Spencer Weart’s APS work. I didn’t know till your post that he had expanded to such a comprehensive web site.

    I looked at a recent paper by Kim and Ramanathan ( J. Geophys. Res., 113, D02203, doi:10.1029/2007JD008434. or It seemed to say they got pretty good results for aerosols/clouds with a Monte Carlo model.

    Assuming the K/R work holds up, how do other modelers incorporate such improvements in their own work? It would seem that other model groups should try to use K/R’s results to change their models and lower the IPCC uncertainty in climate sensitivity or whatever?

    john peter

  17. 167
    Eric Smith says:

    According to Professor Phil Jones, the period 1975-2009 (35 years) had a stastically significant temperature rise of 0.161 degrees.

    That represents 0.46 degree per century, which will have no substantial negative effect on the climate of the planet.

  18. 168
    ferocious says:

    The IPCC AR4 is based on peer-reviewed science, but the report and its forecasts are highly suspect:

    “Using a forecasting method that they have developed, Dr. J. Scott Armstrong from the Wharton School and Dr. Kesten C. Green from the International Graduate School of Business at the University of South Australia conclude that alarm over “dangerous manmade global warming” is the latest example of a common social phenomenon involving alarming but unscientific forecasts that prove to be wrong……..The authors are hopeful that the continuing evidence on the {non}-scientific procedures used by people involved in manmade global warming {forecasting}…… will help to reduce the damage from the alarm in the long run. However, the analogies offered little hope on that score. Most of the previous alarms, such as over DDT and electromagnetic fields, continued to cause substantial harm many years after they had been shown to be false.”

    * Global Warming: Forecasts by Scientists versus Scientific Forecasts Energy and Environment, VOLUME 18 No. 7+8, 2007)(

    “the forecasts in the report(IPCC AR4) … present the opinions of scientists transformed by mathematics and obscured by complex writing”

    All of the forecasts in AR4 are based on parameterized climate models. Such models, no matter how complex, as stated above, are simply the opinions of experts gussied up fancy mathematics and computer programs. The purpose of such a model is ONLY to develop some estimates of how the subject might be affected by changes in the assumptions. Because the parameters(and in some cases even the premises) are adjusted to match particular time series data they are only applicable to that particular time series for that particular time frame It is an elementary excercise to fit data to a curve of some type in order to get some understanding of what is happening. The second step is to show that whatever curve is fitted to a series of data may have absolutely nothing to do with what happens when the data is extended. For example, during a short period, both a sine curve and an exponential curve may give reasonable fits to the data, but neither can actually predict what will happen as more data is collected unless the mechanism underlying the data is understood so one can choose the correct mathematical model.

    Another less publicized, but highly unscientific bit in the AR4 is in chapter 3, p.253. A graph of temperature data from 1850 to near present is overlaid with 150 yr, 100 yr, 50 y, and 25 yr. trends purportedly showing that the rate of temperature increase is accelerating. This is a totally bogus us of graphical techniques. An honest comparison would be a 25 yr. running average, showing that the temperature has gone through several periods of varying rate of change. Using modern statistics you’d go even further and discover that the temperatures anomalies shown(which are a derivative of the the actual temperatues) show non-stationarity, meaning that they are not suitable for any kind of forecast.

    Finally, forecasting can be done scientifically, but it is much less alarming and less fodder for publicity. Peer-reviewed scientific analysis shows that experts are usually very poor at making accurate forecasts. Currently the best scientific forecast, for policy purposes, is that the global temperature rises seen in the last 20-30 years will moderate and reverse back towards some unknown average.

  19. 169
    noel says:

    From #25
    “[Response: Listen to yourself. The next thing will be that the police over-report crime because their pensions are invested in riot-control gear manufacturers, or that people only care about Haiti because they have shares in a T-shirt factory there. This kind of uber-conspiratorial thinking is poisonous to any dialog - take it somewhere else. - gavin]”

    But wait, dismissing skeptics because they might have ties to oil companies is ok? What’s the difference between eg Al Gore investing money in green industries and promoting AGW, and others investing in oil companies and promoting anti-AGW? Double standard much?

  20. 170
    Completely Fed Up says:

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

    An odd “argument” from someone who “claims” to know “things” are different than “stated”.

  21. 171
    Completely Fed Up says:

    “i suggest that you contribute with something substantial or be quiet”

    I suggest you give positive information or be quiet.

  22. 172
    Jack Kelly says:

    Excellent write up, as usual. Many thanks.

    Fern #8, 14 February 2010 @ 5:00 PM wrote:

    …There’s just one thing that still gets me: when will they fianlly lay to rest this “-gate” thing? Total lack of imagination!!!!

    MetaGate: The scandal whereby journalists lack the imagination to come up with a better suffix than “-gate”.

  23. 173

    [...] covers the Journalismgate scandal, where a couple of dishonest reporters (Jonathan Leake and David Rose) [...]

  24. 174
    Radge Havers says:

    Bob @ 146

    “And this is part of the problem. The layman not only is poorly trained in science, but they are also poorly trained in critical thinking and clarity in writing (and reading what is written).

    You can’t win with those people, because they are too easily mislead, either by their own confusion, or the lead of someone else who is confused.”

    Add to that that they’ve been purposely wound up with some simple off-the-shelf ideology, ‘empowerment’ and a sense of entitlement about their gut instincts. It’s a complex mess. It reminds me of a situation I witnessed on a much smaller scale a number of years ago. Basically MBAs trashed a department using an inverted pyramid for an informal org chart during a time of institutional crisis. The director went into hiding; the secretaries went on a rampage, venting over any and all of their pent-up frustrations, and basically ended up in charge–even to the point of holding angry inquiries over the state of the “business model.” I kid you not. It was the weirdest thing I thought I’d ever see until the change in government unfolded in the years after 2000.

  25. 175
    Completely Fed Up says:

    steve says:
    15 February 2010 at 9:50 AM

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

    Have you read G&T’s paper? Have you read blogs like the ones on the BBC?

    There are plenty of people who refuse POINT BLANK that CO2 can have anything to do with temperatures.

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

    There is. Please can we have more skepticism and less denial.

    Your help in this matter is appreciated.

    “Hard data? Is there any other kind?”

    Yeah, there’s the “made up data” that make people report 0.1C per doubling is what CO2 sensitivity is.

    Almost all of it is found in those people denying the scientific conclusion of AGW.

  26. 176
    Rich says:

    M.Cejnar says:

    “Rich, you miss the point entirely. This is not a typo in a just-released report. AR4 has been around for 3 years and this 2035 was originally challenged but was included anyway. It has subsequently been publicized and has been “settled science” and “accepted by thousands of scientists” for 3 years.”

    Apparently, M. Cejnar failed to read the reference cited. I am not defending the IPCC (although I do believe in climate science).

    “If scientists could not or were afraid to denounce an absurdity in the AR4, then this makes all other data in the AR4, legitimized by the same thousands of scientists, also untrustworthy.”

    Falsus in uno, falsus in omnibus is a logical fallacy.

  27. 177
    ferocious says:

    re 55 and 56:
    Before you even look at the data you decide on how important the conclusion is going to be. The more important, the more strict the statistics. 95% confidence interval has been traditionally used because it is wide enough to be attained in many instances, but robust enough that unfounded conclusions aren’t very likely be made. The AR4 even equates confidence intervals as low as 90% or even 80% with words such as “likely”. What that really means is that you are likely to be wrong if you accept the advice.

    The idea that a trend “is quite close to the 95 per cent significance level” is merely wishful thinking. I can remember more times than I care to count when I went ahead based on a test “being ‘close’ to the 95% CI and found out that the 5% error is very real, and will come back to bite you!

  28. 178
    Completely Fed Up says:

    “We are told that the new record is due to “extreme weather” caused by “global warming.””

    Global warming (no quotes) will cause more extreme weather.

    There’s more energy in the system (expressed as temperature).

    What happens with a more energetic system?

    More stuff.

    Is it the cause of that incident?

    Can’t tell because one incident is weather, not climate. And global warming is a climate event. By the time you know it’s there it’s been happening for a generation.

    It is a bit late to act against it at that point…

    Oh, PS, for Andreas Bjurström, where were you when Baghdad Bob turned up?

  29. 179
    Completely Fed Up says:

    “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”

    Did you read anything?

    The Sun.
    The Daily Mail.

    You just went on and guessed for BBC/C4? (which, by the way, had C4 promote that POS global warming swindle that had severe edits to avoid criminal sanction).

  30. 180
    Completely Fed Up says:

    “As I said, grow up. Post Climategate is the first time the (UK) MSM has turned on you after decades of unquestioning acceptance”

    As I thought. You need to grow up.

    No, this isn’t the first time MSM has turned on AGW. And they’ve never (not even for days, never mind decades” showed “unquestioning acceptance”.

  31. 181
    Dennis says:

    Andreas Bjurström wrote: “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.”

    The IPCC only has an “arrogant scientific attitude” if you can point to a large body of relevent, peer-reviewed scientific literature that it ignored. To my knowledge, no such body of literature exists.

    The IPCC is simply stating the current understanding of the science. If it didn’t, there would be thousands of climate scientists out there complaining that the IPCC had misstated their conclusions. To my knowledge, no such complaints exist.

    Now, if you want to argue that the vast majority of the world’s climate scientists are engaged in some sort of massive consipracy to distort the scientific truth and dupe the IPCC into complicity, feel free to do so.

  32. 182
    AxelD says:

    Ray @137 claims (of IPCC bias in errors) that ” … actually, they aren’t. The IPCC is clearly way too conservative in the way it treats the cryosphere.”

    Not sure the ex-Chairman of the IPCC agrees with you, old chap. Dr Robert Watson (IPCC chairman 1997-2002) says in a Times report today that “The mistakes all appear to have gone in the direction of making it seem like climate change is more serious by overstating the impact. That is worrying. The IPCC needs to look at this trend in the errors and ask why it happened.</i"

    Darn, is that pesky press telling lies again? Except that, hang on, I think that Dr Robert Watson may be rather more trustworthy than the current IPCC chairman. What do you think?

  33. 183
    Ike Solem says:

    The main goal of the fossil fuel lobby (in their own words, courtesy of the American Petroleum Institute) is to “create doubt about global warming science” in the minds of the general public, journalists, politicians and policymakers.

    To do this, they rely on loud attacks on climate scientists & their publications, and on international institutions like the IPCC. The general theme is, the more scientists get smeared or degraded in the press, the more likely it is that the public and politicians will view the science as uncertain.

    If you want to see where this model originated, there are many fine books on the history of the effort to regulate tobacco smoking based on the scientific assessment that smoking causes cancer and lung & heart disease – or should I say “exacerbates” instead of “causes”?

    What’s interesting about the most recent attack on the IPCC is that it was quickly parroted by the Washington Post (“Series of missteps by climate scientists threatens climate-change agenda”) as well as the New York Times (“Skeptics Find Fault With UN Climate Panel”) and the Wall Street Journal (“Climate group admits to making mistakes”) and also by CNN (“UN climate chiefs apologize”) – that is the same CNN that fired Miles O’Brien and the rest of the science staff when they started running accurate reports on Arctic thawing and polar bear starvation.

    However, these press outlets are ignoring the biggest flaws in the IPCC process, which are to be found not in the (rather conservative) scientific assessment in working group I – which entirely neglected carbon cycle feedback processes like permafrost melting, by the way, but rather in the “adaptation and mitigation” report produced by working group III – the real stinker, in my opinion.

    In particular, see the long-winded and scientifically unsupported parroting of “clean coal carbon capture” claims in Chapter 4, WG3, pg 292: (it’s a 15 MB pdf file, the entire chapter:)

    How much time do they give to real renewables? Not much. Rather than a blueprint for replacing fossil fuels with renewable energy on a global scale, many sections of the WG3 report are little more than a series of talking points lifted the fossil fuel lobby’s deception program.

    About that deception program: In the fossil fuel anti-science PR world, the first effort has been to convince the public and government officials that global warming isn’t happening. That failed, mostly. The next themes were “it’s happening, but it’s not because of fossil fuels” and “it’s happening, but it’s going to be beneficial.” Again, all those notions have been shown to be wrong, despite the long-winded efforts of the denialists.

    Faced with this reality, the fossil fuel lobby is now moving to deception instead of denialism as its core PR strategy. The new claim is that they can go through with their plans to use dirtier oil sources – the list includes heavy oil, tar sand oil, shale oil, coal-to-liquid and coal-to-gas schemes, and enhanced oil recovery schemes – all without releasing CO2 to the atmosphere. In reality, all five approached are at least twice as fossil CO2-intensive as producing and refining light sweet crudes, which are no longer available in many cases.

    A massive PR program is being pushed to convince the public that this can be done “cleanly” and that coal gasoline and tar sand syncrude are in reality, “clean energy sources”. That’s the deception program, the new adjunct to the ongoing denialist program.

    The IPCC WG3, rather than rigorously reviewing the science behind such fossil carbon capture claims, simply reprinted ridiculous unsupported estimates – it reads like the literature put out by the coal-financed FutureGen Alliance, or by the ACCCE, or by the DOE Carbon Capture program.

    Despite all the hoopla and bipartisan political support for “clean coal” including billions in DOE taxpayer financing, it’s never been demonstrated – and yet, for some reason, the U.S. media chooses to focus on a few tiny errors in the working group I analysis – while entire ignoring the nonsense in the working group III analysis.

    Looking at this, one can really only conclude that many academic and media institutions in the U.S. and around the world have been thoroughly corrupted by the influence provided by the fossil fuel industry and their associated financial dependents – to the point that they’re not really doing science or journalism anymore, but rather just working to promote various talking points.

  34. 184
  35. 185
    Martin Vermeer says:


    If anything, I would
    like to see the climate change happen, so the science could be
    proved right

    Yep, I share the sentiment. He (like me) doesn’t want AGW to be true… that train left the station long ago. He wants its truth demonstrated, as in: I told you so.

    …and frankly, after the way the world has treated him, I suspect the sentiment has grown. ‘Go ahead assholes, make my day.’

  36. 186
    Andreas Bjurström says:

    The second half of this statement (from the realclimate article) is false:
    “The IPCC cites 18,000 references in the AR4; the vast majority of these are peer-reviewed scientific journal papers.”

    This statement is true only of Working group 1. I have done quantitative studies on this issue, so I have rather deep knowledge and lost of quantative data. Sp please reply if there is interest to know more on this issue, or perpaps even nuance the statement in the article itself.

  37. 187
    robert says:

    Please help me understand the timing of glacier retreat. It probably has been addressed somewhere but I cannot find.
    During last glacier advance(approx 20K years ago) glaciers in the US reached down to about NYC(40 degees north) in some parts. When the Spanish were exploring in the 1500′s they were able to sail (ice free) to about Baffin Island the southern part of which is about 60 degrees north. This represents a 20 degree retreat or about 1200 miles. Taking some numbers from the Himalayan Glaciers of 100 meter retreat per year a 20 degree retreat would take about 18K years. So what is so unusual about the current glacier retreat?
    I realize above is comparing different geographies but I would like to get a handle on any acceleration of the normal rate of glacier retreat.

  38. 188
    Ghost of Christmas Yet to Come says:

    Somehow global warming just doesn’t sound very threatening. Scientists are cold-blooded people, and they’re not talking enough about how degraded and squalid the Earth will increasingly become if carbon emissions continue. Or even the devolution that is already occurring and has occurred from the pollution already there for the past 30 or so years. As it is, it doesn’t sound like something to be very worried about. “So it will get a little warmer, so what.” You need to talk about things like, how beauty will vanish forever, or how poor nutrition (from bee extinction and the erosion of agricultural products from carbon pollution) will cause children to become increasingly deformed and mentally retarded. Draw parallels between projected extinction events, like the Polar Bear, and human beings, show a TV commercial with a little blonde girl stranded on a melting ice flow going over a giant water-fall. Things like that. That’s the way the “vested interests” play. All theses numbers and graphs don’t leave much of an impression. No matter how correct they are. The 1960s and 1970s were far more savvy about this. With the little blonde-hippie girl picking flowers as a mushroom cloud looms over head, and Iron Eyes Cody weeping over a congested traffic turnpike, etc. Scientists are too politically correct these days.

  39. 189
    MarkB says:

    Good response by Bob in #154 to Ruth in #96. Saying the evidence doesn’t support equal or higher warmer global average temperatures during MWP isn’t the same thing as saying the possibility is completely ruled out. This is entirely consistent with RC’s statement and work that Dr. Mann has done.

    A recent study perhaps sums it up for the northern hemisphere:

    “The strongest result relates to the temperature of the last decade, which exceeds any decade prior to 1850 with 95% certainty. The increased certainty compared to the 66% certainty expressed by IPCC2001 is primarily a consequence of the continuing high temperatures which have made the last decade 0.24 K warmer than the last decade of the 20th century, a warming greater than one standard deviation of the reconstruction uncertainty.”

    It’s also entirely a red herring to use past climate change as evidence against manmade global warming, as contrarians obsessing over the MWP assert. A more variable past climate is arguably evidence for higher climate sensitivity.

    The amount of quote mining and distortion among ideologues is quite disconcerting. I would think this would turn off objective observers looking for good faith analysis. The recent spin over comments made by Dr. Lacis regarding a draft IPCC summary is one textbook example. Lacis had to set the record straight:

    “There is a great deal of irony in this basically nonsensical stuff, some of which I find rather amusing. The global warming denier blogs, where this issue first came up, seem to think that I was being critical of the I.P.C.C. report in the same way as seen from their perspective, and, as a result, I have received e-mails from the denier crowd hailing my remarks and commending me for “speaking up” on this important topic.

    Little do they realize that the basic thrust of my criticism of the I.P.C.C. draft was really to register a clear complaint that I.P.C.C. was being too wishy-washy and was not presenting its case for anthropogenic impact being the principal driver of global warming as clearly and forcefully as they could, and should.”

    “Had I been asked to write this chapter (which I wasn’t), I would describe “understanding and attributing of climate change” as simply a problem in physics, which it actually is. I would have started the Executive Summary with: Human-induced warming of the climate system is established fact.”

    I suppose that is another example where the IPCC should have stated their case more firmly. They tend to water down analysis to the lowest-common-denominator. Sea level rise is another example.

  40. 190
    Completely Fed Up says:

    AxelD says:
    15 February 2010 at 12:10 PM
    Not sure the ex-Chairman of the IPCC agrees with you, old chap. Dr Robert Watson (IPCC chairman 1997-2002) says in a Times report today”

    Would this be the same Times that completely made up Latif’s words?

  41. 191
    Completely Fed Up says:

    Ferociously wrong: “The AR4 even equates confidence intervals as low as 90% or even 80% with words such as “likely”. What that really means is that you are likely to be wrong if you accept the advice.”

    No, that would be the result of accepting “unlikely” advice.

    If you *reject* likely advice, then you’re likely wrong. Not if you accept it.

    Please also remember that “wrong” also includes “ohshit, we’re gonna die”, which is hardly a reason for inaction.

  42. 192
    Andy says:

    Whistling past the graveyard are we?

  43. 193
    Completely Fed Up says:

    “But wait, dismissing skeptics because they might have ties to oil companies is ok?”

    No, but when you dismiss “skeptics” (actually deniers) because they don’t have any science behind them, you can also find that they have oil companies behind them.

    does their backing by oil companies mean they don’t have to have science on their side?

  44. 194
    Completely Fed Up says:

    John says:
    15 February 2010 at 11:21 AM

    So Pachuari did not mention it in a speech pre-Copenhagen then? Please.”

    He did.

    So what?

    If it were there to scare people, it would be rather more prominent.


  45. 195
    Ken W says:

    Les (74) wrote:
    “The temperature trend is positive. But not significantly. Its outside the 95% confidence level. … Since 1995.”

    If the question were rephrased to be 1992 to present or 1993 to present, you’d get a different answer. In other words, the question is a red herring.

  46. 196
    Andreas Bjurström says:

    Dennis, I do not argue for conspiracy. I am not a simplistic sceptic. I am a social scientist doing research on the sociology of climate research. I believe that we are experiencing climate change that should be mitigated and adopted to and so on. Satisfied? Now, this is what I tried to state:

    First, all I need to show that the IPCC is ignorant is a single case. Yes, we have that case. Pachauri has been rather ignorant lately. He deny, deny, deny, than after intense pressure he admit, yet just a little little litte. All is soo perfect, almost completey perfect …
    The IPCC statements of january 2010 are also rather ignorant. There are of course more errors, the peer review process is not almost perfect, etc etc. So many issues are overstated. Which is sad, cause this is exactly how the IPCC makes it too easy for the sceptics. With a more humble attitude, occasional errors would not be a big deal.

    I claim that the vast majority of the world’s climate scientists are natural scientists (I also have quantified data on this and two scientific articles and a number of conference papers on this and related issues). I also claim that most natural scientists lack adequate knowledge on societal issues. This results in many things, e.g. a naive understanding of the role of science in policymaking. Neglection of the subjective side of science, the role of power and values in framing climate change, etc.

    The IPCC also ignore a large body of significant knowledge. Almost all social science is ignored by the IPCC. The IPCC is a natural science technocratic assessment combined with economic science (yes, I have data that demonstrates this as well).

  47. 197
    SecularAnimist says:

    The RC group wrote: “We will follow with great interest whether the media world has the professional and moral integrity to correct its own errors.”

    In the USA, the “media world” consists almost entirely of a handful of giant corporations that own and control virtually all of the mass media from which most Americans get most of their information.

    Those corporations do not use their near-totalitarian control over the mass media to impartially inform and educate the American people about important issues as a public service, out of the goodness of their hearts.

    Instead, they use the mass media to (1) make a profit and (2) to relentlessly propagandize the American people in furtherance of corporate interests and the corporate agenda.

    The fossil fuel corporations are among the largest, wealthiest, most powerful, most far-reaching commercial enterprises in the world — and they have shown themselves to also be among the most rapacious and ruthless and reactionary corporations in the world.

    And it is the fossil fuel corporations’ agenda that directs and drives the corporate-owned mass media’s deny-delay-obstruct-confuse-and-create-doubt propaganda regarding anthropogenic global warming.

    Terms like “professionalism” and “moral integrity” are properly applied to journalists, not to dishonest, bought-and-paid-for corporate shills.

  48. 198
    J Bowers says:

    168 noel says: “But wait, dismissing skeptics because they might have ties to oil companies is ok? ”

    I thought these “sceptics” only had ties to concerned charitable or non-profit organisations and think tanks? Interesting. So you admit that they have ties to oil companies.

    We’re getting somewhere at last.

  49. 199
    Garrett Jones says:

    At your suggestion, I went and read the BBC Q&A. A couple of points, whatever and whereever the truth may lie, you need to get Dr. Jones to shut up. His explanations contribute more to confusion than clarity. Public speaking may not be one of his skills, find someone who is better at it. Second, he needs to get a better lawyer. From the US prospective, some of his anwers appear to be laying a defense for sloppiness instead of fraud, and not a very good defense at that. He needs to shut up before he talks himself into criminal charges.

  50. 200
    Didactylos says:

    AxelD: One out of one errors are in the positive direction. Hardly something to derive a conclusion from.

    In this case, I don’t trust the Times to report accurately. They have failed to do so far too often.

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