Comment on EER interview with Fritz Vahrenholt


Also published in European Energy Review (EER).

Greenhouse gases are responsible for warming, not the sun

Scientists working on climate on a daily basis must have been rather astonished by the interview with Professor Fritz Vahrenholt (European Energy Review, May 2, free registration required). Vahrenholt, chief of RWE Innogy, self-proclaimed climate expert and author of the book Die Kalte Sonne (The Cold Sun), claims that “the contribution of CO2 to global warming is being exaggerated”. These claims, however, do not stand up to scientific scrutiny. We assess his ideas in the light of the scientific literature on the role of the sun versus other climate forcing factors. The dominant influence of greenhouse gases follows not only from their basic physical properties, but also from their “fingerprint” in the observed warming. The sun, in contrast, has not exhibited any warming trend over the past 50 years. The sun is thus not responsible for the warming seen during this period. Greenhouse gases in all likelihood are.

First of all, we welcome the active participation of the business community in the discussion on climate change. Global warming and its effects may have consequences which business, e.g. the energy sector, should anticipate and adapt to. Furthermore, mitigation policies may affect the competitive advantages and business prospects of a variety of energy options. Investment portfolios should take that into account. That is not an easy task. The business consultant or director developing a climate change response strategy may be overwhelmed by the vast amount of –sometimes conflicting- scientific information available. Luckily, every couple of years an integrated assessment is made by the IPCC, the Intergovernmental Panel on Climate Change, primarily aimed at governments, but also quite valuable for the business community.

Of course, opinions differ regarding how well the IPCC assessment reflects the scientific understanding, with some claiming that IPCC overestimates the human contribution to global warming and the risks it poses, whereas others claim that these are underestimated. However, the main tenets of climate science, as described in working group 1 of the IPCC report, have proven to be robust: New research has confirmed the core conclusions, while the details are continuing to be filled in. Vahrenholt’s claim that the IPCC report is radically wrong is unfounded, and is mostly indicative of his views diverging from mainstream science.

This is not to say that no uncertainties remain; of course there are and in some cases they are inconveniently large. Inconvenient, not only because more research is required to further constrain these uncertainties, but also because the uncertainties go both ways. The human contribution to global warming could be somewhat smaller, or it could be somewhat larger than expected. Focussing only on aspects that downplay the anthropogenic contribution is closing one’s eyes for the whole picture.

Challenging the core tenets of climate science is easier said than done.  Varenholt’s extraordinary claim requires extraordinary evidence. The least one would expect of such a claim is that it be put to the scientific test. Spectacular theories and speculations abound in books and on the internet, but most of them were not offered to the scientific community, or did not stand up to scrutiny if they were. Scientists routinely check each other’s work via the peer review process, which can be seen as a first test of scientific validity. From further discussions in the literature and other scientific fora the relative robustness of competing ideas is assessed.  The most robust idea eventually gains acceptance. That is how science progresses. Surely the peer-review system is not perfect, but at least it is an organised process aimed at filtering what is possibly right from what is plainly wrong.  Such a mechanism is lacking in the public debate; and that adds much to the public confusion about this and other complex scientific topics.

Now, would the ideas of prof. Vahrenholt stand up to scientific scrutiny? On the basis of the interview, we expect: no, they would not. However, we would still encourage him to submit his ideas for scientific review. That is where the physical forces and feedbacks in the climate system should be discussed.  On the other hand, questions on how society and politics should respond cannot be answered by science, but should be discussed in the public and political debate. Unfortunately, Vahrenholt’s accusations like “we are being misinformed by the climate establishment” and “the whole purpose of the IPCC has been to get rid of the so-called Medieval Warm Period” betray him as being receptive to conspiracy theories, which are routinely echoed on the internet. In such a world view, any criticism by the scientific mainstream is of course only perceived as proof that his and similar views are being suppressed. This is often used as an excuse to not even try to submit one’s ideas to peer review. His book is criticized by scientists not because it would be politically incorrect, as Vahrenholt assumes, but because it is scientifically incorrect.

Now, if we take a closer look at the content of Vahrenholt’s theory, his key statements appear to be the following:

  1. The ‘hockey stick graph’ showing that global average temperatures are now higher than in the last 1500 or so years is flawed. The medieval warm period was about as warm as today, the Little Ice Age was globally very cold and both periods coincide with a more, respectively less active sun. Therefore, the IPCC underestimates the natural variations of our climate system.
  2. The IPCC fails to look at all the solar characteristics, focusing on sunspots and Total Solar Irradiation (TSI) only, while both fluctuations in the magnetic field and the amplifying feedbacks should also be taken into account.
  3. The sun has become more active over the past few hundred years, being responsible for a large part of the observed warming.
  4. The IPCC has underestimated the natural 60 years climate cycle dominated by the Pacific Decadal Oscillation (PDO) and the Atlantic Multidecadal Oscillation (AMO).
  5. Global warming has stopped since around 15 years.

On this basis, Vahrenholt claims that more warming is due to the sun and natural variability than the IPCC estimates, which automatically implies that less is due to CO2 than the IPCC says. 

To begin with the last statement, the idea that global warming has stopped is a common misunderstanding, based on confusing short term variability with the long term underlying trend. Natural fluctuations, as caused by e.g. the solar cycle, volcanic eruptions, or by the El Nino/La Nina phenomenon, can mask the underlying trend in surface temperatures for more than a decade. When these effects are accounted for, as e.g. Foster and Rahmstorf did in 2011, the underlying trend is seen to continue unabated. Moreover, other measurements, e.g. of ice extent and of ocean heat content, confirm that global warming is continuing.

The solar activity has been well-measured, particularly since 1979 using satellites, and before that by indirect (“proxy”) measures. From these, the solar activity is seen to have been relatively stable over the past 50 years. That means, that even if amplified strongly, the sun’s variations could still not explain the strong global warming that started halfway the 1970’s. Measurements of cosmic rays, a favourite candidate for a solar amplification mechanism, also show no trend since at least 50 years. The robust evidence needed to become a serious scientific competitor for the dominant greenhouse mechanism is sorely lacking. It is true however, that the sun gained strength over the first half of the 20th century, and thus contributed to warming seen during that time, as is also described in the IPCC report.

Figure showing temperature, CO2 and solar activity for the past 150 years, discussed in more detail here.

Various solar and climate physicists, like Lockwood, Haigh, Gray and others have published analyses indicating that the solar influence in the warming of the last half century is low or absent. These analyses include the magnetic field effects, which – in contrast to what Vahrenholt is saying – are not neglected by the IPCC. A few years ago, Pierce and Adams modeled the potential cloud forming effect of cosmic rays and found it wanting by more than an order of magnitude, even when the most favourable assumptions possible were made.

There is another indication to the statement that the sun’s role in warming is limited compared to the role of greenhouse gases: fingerprints. Each possible source of warming leaves a specific and characteristic fingerprint. For example, a solar fingerprint would be: warming throughout the atmosphere. A greenhouse gas fingerprint would be: warming at lower altitudes with simultaneous cooling of the stratosphere higher aloft, since in case of enhanced CO2 the stratosphere loses more infrared radiation than it receives from below. This is mainly a consequence of the temperature structure of the stratosphere. And guess what? Measurements clearly show a greenhouse gas fingerprint, not a solar one.

In addition, Vahrenholt claims that IPCC has underestimated natural variability, in particular a natural 60 year climate cycle manifesting in the purported Pacific Decadal Oscillation (PDO) and in the Atlantic Multidecadal Oscillation (AMO). However, Vahrenholt’s statement is based on curve fitting applied to a finite time series of (local) temperatures. It is well known that curve fitting to a series of chaotic signals can lead to apparent periodicities, but that these have no value for prediction unless they are supported by an underlying physical understanding. 

From this quick analysis, it seems unlikely that Vahrenholt’s claims would stand up to scientific scrutiny. They should be taken seriously, but only as an idea that deserves further research and assessment, rather than as a scientific fact or theory that rises to the level of robustness of basic climate science. In that respect, the physical science basis of the IPCC 2007 is still strong. Vahrenholt’s ideas do not change that conclusion.

Dr. Rob van Dorland (KNMI)

Dr. Bart Verheggen (PBL)

Postscript: Fritz Vahrenholt and his book co-author Sebastian Lüning responded at EER to our comment. Our complete reply to their response will be published here separately.


Tags: , , , , , , , , , ,

51 Responses to “Comment on EER interview with Fritz Vahrenholt”

  1. Tom Fuller Says:

    I happen to agree with your reasoning, Bart. I also happen to think that reasonable questions remain about the scope of global warming as well as its impacts.

    Solar activity is not enough to explain the Current Warming Period. However warming to date shows no sign of approaching levels that many fear will come. Nor does sea level rise.

    I’m off to read Vahrenholt’s reply.

  2. Bart Says:

    warming to date shows no sign of approaching levels that many fear will come

    Patience, Tom, patience. Especially when it concerns a slowly changing signal amidst a lot of noise. It is the interplay of the many influencing factors (some long term, some short term), that determines what the global temperature evolution looks like. And some random noise to top it off.

  3. Eli Rabett Says:

    Bart, excellent writing, one quibble, instead of

    On the other hand, questions on how society and politics should respond cannot be answered by science, but should be discussed in the public and political debate.

    Perhaps it would be better to say something like

    While questions on how society and politics should respond cannot be answered by science, but must be informed by science in the public and political debate.

    This is basically MTs position which the Tolitarians try and jump on, but if what we know is not a major part of deciding what we shall do, why learn?

  4. thomaswfuller2 Says:

    When the trollitarians attack the Tolitarians in defnse of the Tobitians, you can’t tell the players without a scorecard.

    But it’s easy to recognize a straw rabbit. For of course nobody thinks participants in the debate should check their knowledge at the door (although some would do well to check their premises–and their attitudes).

    What distorts the debate (and purposely so) is when someone says I am an expert on butterflies and so when I tell you the people of India are doomed to starvation and we should abandon them, you must heed me. Thank you Paul Ehrlich, but what we should do is ignore you.

    Knowledge in one field does not imply knowledge of another. Someone may know dendro but not statistics, for example.

  5. Bart Says:

    Eli, quite right. Science should inform the public and political debates. For now, we thought making a clear distinction between the question of “is” and the question of “should” was most important.

    Tom, are u trying to provoke another mudfight? Please don’t. You’re creating a strawman argument btw. Saying policy deliberations should take account of scientific knowledge is something entirely different than saying the science demands we undertake such and such specific measures.

  6. Eli Rabett Says:

    Science has come quite far in the last 100 or so years. As Arthur Clarke said, an advanced enough science looks like magic to most people, and magic, is, well, one is taught to be quite skeptical about magic. It’s a trick, don’t believe it. And that is very hard to push through.

    Where folk like Fred Singer and Tony Watts (Eli may call you Tony, yes? Well at least here) hurt is that they encourage this belief. To a small extent Singer at least is trying to walk it back, but he really cannot, because if he does walk it back then his muddying the waters collapses (to strangle a metaphor).

  7. Tom Fuller Says:

    Bart, I don’t think it’s a strawman. How many examples do you want of scientists who ventured a bit far from their field and advocated public policy positiions, using science as their validation–things like eugenics… locked hereditability of intelligence… harm from GMOs…

    There is a track record of this type of thing. Fortunately it is not limited to scientists and hence we can take it as evidence of humanity. Except in a few cases.

    This doesn’t make Varenholt right. He is not. It leads, however, to very strong indications that Rabett is wrong. Especially when he completely misunderstands Clarke’s quote, a quote that’s been around for decades and is frequently used in climate discussions.

    Bart, if you made a presentation on aerosols I would vouch for its honesty, at least. But if you made a presentation about communications in the climate debate I would caveat any comments I made about it. And if you proposed any policies regarding the communications about climate change or climate science, I would be dubious to say the least.

    Not because of bad faith or intent, although it’s clear you’ve chosen sides. But because there is a body of work, best practice and learnings about communication that I see no evidence of you having read.

  8. Bart Says:


    Your comment seemed to be in response to Eli, who wrote

    While questions on how society and politics should respond cannot be answered by science, but must be informed by science in the public and political debate.

    That should be an entirely uncontroversial statement. Or should the public and policy debate not be informed by science (amongst other things)?

    I’ve not “chosen sides”, unless science can be regarded as a “side”. As I wrote on the open thread in response to Paul, we need to get away from science being portrayed as a side. Because that feeds into the cultural disposition to accept or reject science (dependent on whether one views its conclusions as being in line with one’s side). Society is not served well by such a dynamic.

    PS: In case you want to bring up specific examples, please do so in the open thread.

  9. Tom Fuller Says:

    Rabett changed your ‘should’ into a ‘must’. He thinks Curry’s and Watt’s websites should be shut down. He doesn’t want a public or political debate. He wants to hand us his orders.

    You’re not like that. And I agree that if science is considered a ‘side’ it all will end in tears, because the other ‘sides’ will have more guns.

    But there has to be a way for you to present your attitudes, opinions and perceptions that is separate from those that others, like Rabett, would present and justify as coming in science’s name. He and those like him take a ‘free ride’ on your hard-earned reputation for honesty and fair play.

    You need to figure out a way to deal with the Rabetts of this world, just as honest skeptics and lukewarmers have to figure out how to deal with the Moncktons. Neither side has done very well on this.

    Note how the differences between you and Varenholt are captured in a civil fashion. Note that by responding to his last statement first, you put his argument about the hockey stick into perspective in a natural fashion, without making a big deal about it. 9That’s good communication, Bart–but you should be prepared to respond further.)

  10. andrew adams Says:


    Bart and other scientists may not have read lots of papers on science communication but it is something they are actually involved in on a daily basis, so I don’t see why they shouldn’t have a valid perspective on policies for effective communication. As indeed might a non-scientist like myself who is on the other end of such communication.

  11. Tom Fuller Says:

    Hi Andrew,

    Bart’s actually been writing about science communication, here at at P3. I’m trying to respond to what he’s writing. I’m not convinced he started from the most useful premise yet. I don’t know if overcoming an information deficit is a useful goal, achievable or even necessary.

  12. Tom Fuller Says:

    If I were in Bart’s position (and I’m glad I’m not), I might try and use the Hockey Stick as an example of how science, policy and communication interact.

    It would be simple and illustrative.

    (Part 1)

    Scientists who study climate change realized that it would be useful to understand if the warming we’re experiencing now was replicated in the past 1,000 years, a period where the quality of available data is not as good as recently, when we have thermometers and records, but much better than earlier periods when age makes evidence much more uncertain.

    After all, if warming happened on a regular basis, what we might be seeing now could just be natural and not caused by human emissions of CO2. And since there are several causes of warming, if we could look at what happened before we started large scale emissions, it might help us apportion our contributions to the current warming. If we can do it, it would be helpful in several areas.

    Some thought that the science of dendrochronology might shed valuable clues. Tree rings vary in width depending on a variety of factors–age, moisture, soil quality, surrounding trees that might affect sunlight falling on a particular tree, etc. But one factor is also temperature. Some trees grow faster when temperatures are warmer and their tree rings are wider as a result.

    Doing it successfully is really complex.

    (I may try and continue this…)

  13. Bart Says:

    Tom, if you do, then please on the open thread. Or I may even open a hocekstick thread one of these days…

  14. Tom Fuller Says:

    Okay, Bart. I gotta read a paper referenced by
    BBD anyhow, so I’ll move over there.

  15. Eli Rabett Says:

    Saying that the public debate not be illuminated by what we know is an appeal to ignorance.

  16. Tom Fuller Says:

    Nobody’s saying that. What people are saying is that expertise in field A does not give you a right to claim expertise in Field B.

    William Shockley shared a Nobel Prize in physics for his work on the transistor. That did not make him an expert on evolution, the heritability of intelligent or race.

    Paul Ehrlich is an expert entomologist specialized in butterflies. That does not give him the right to expect deference on famine.

    Charles Davenport was a prominent biologist. That did not give him the right to expect deference to his opinions on eugenics.

    Bart Verheggen is a scientist on aerosols. That does not give him the right to expect deference when he writes on communication with the public. (He doesn’t ask for it, but…) Nor does it give him the right to expect deference when he speaks on policy measures to address sea level rise.

    I’m glad he writes about these things. I welcome his opinion. I pay attention to what he says because he is sane, intelligent and usually compassionate. But not because he studies aerosols. That brings little to bear on the subject we are discussing.

    In another world I would entertain the idea that the fact that he studied science and learned a certain way of thinking and a method of investigation would give him a certain pride of place when discussing issues, even those outside his area of competence. Those years of study and work would count for something.

    But that other world wouldn’t have an Eli Rabett who embodies the opposite qualities demonstrated by Bart Verheggen and proving that scientific study and work cannot be a proxy for intelligence and diligence.

    Pity, that.

  17. Eli Rabett Says:

    Now some, not Eli to be sure, might encourage Mr. Fuller to stop taking majic mushrooms. His habit of replying to the imaginary image of others he has painted in his mind is a sure killer of any discussion.

    To be constructive, exactly what separates Bart and Eli on the broad outlines of what the Earth confronts. Not much, both of us agree that without drastic action the future is grim on a number of fronts. First climate change, where both Eli and Bart have some learning, and where the fuse is lit and we have less than a century to take action. There both Bart and Eli agree that the fast driver is humans increasing greenhouse gas concentrations in the atmosphere. We might differ about the exact time schedule and the level of harm to be expected by the end of the century, but there is always the century after. Things will not get better on the current track.

    Second, in an area where both Eli and Bart listen to others who have some learning, it looks like we are headed for a sixth mass extinction, and the loss of vital natural services, again, within a century.

    That, is the science that essentially all climate and ecological scientists agree to and should form the background of any discussion about what to do.

    Bart and Eli do have differences about how to bring about some chance of ameliorating these approaching disasters. Bart thinks that better communication to those opposing action is called for. Eli is somewhat older and more cynical, and thinks that this is basically futile because it assumes good will among the core of denialists who oppose action for economic and political power. They will not be persuaded, they will resist.

    Still, another way of looking at it is that Bart is targeting those that can be persuaded, Eli is looking to show those who can be persuaded that they are following, well, let the Rabett say it, folk like Tom Fuller, which is good neither for their health nor the world’s future.

  18. andrew adams Says:

    Hi Tom,

    I think that whether the information deficit approach is useful depends very much on the audience one is trying to reach. I think that there are plenty of people out there who do have genuine doubts but feel they don’t really know enough about it to have a strong opinion and would certainly be persuadable if someone explained the basic arguments to them in a way understandable to someone with either a fairly basic science background, or indeed none at all. Of course those kind of people don’t tend to take part in discussions on climate blogs so reaching them can be difficult, although I guess some may read them without actually commenting, which to be honest is the only thing that might make a lot of such discussions worthwhile. I’ve found in general that discussions about climate on general political blogs can be more productive because there are more people there with an open mind on the subject, although they still don’t tend to attract the average Joe in the street.

    Clearly though this aproach will not work with those who have already made up their mind, in fact my experience tells me that the large majority of such people are not persuadable at all. To the extent that some might be persuadable it is likely to be through seeing the weaknesses in many “skeptical” arguments exposed, and I don’t think that exposing bad arguments is ever a bad thing, but in general I think we just have to accept that there is a significant and vocal minority who will always oppose action on climate change and we have to work out how to move forward despite their opposition, rather than think we can win them over. In this sense climate change is just like pretty much every other political issue on the planet.

  19. andrew adams Says:

    On the wider question, as someone with very few scientific credentials it does seem reasonable to me that in principle someone with a strong scientific background, especially in physics, would be better placed than someone like me to evaluate and discuss in detail an issue such as climate change, and indeed other scientific questions, and I think that this indeed often the case.
    But having said that, it is also very apparent that highly intelligent, well qualified and very scientifically literate people are capable of talking almighty nonsense on subjects outside their particular field. They will often cite their own qualifications as a reason why their views should have credibility but it seems to me that this is just giving them false sense of confidence in reaching misguided and/or preconceived conclusions. Ironically they will dismiss any reference to the views of those actually active in the field of climate science as an unreasonable appeal to authority, and of course they would be extremely dismissive of outsiders voicing equally confident opinions on their own particular field.

  20. andrew adams Says:

    One final point. I don’t agree that the hockey stick would be a good basis for discussions about science, policy and communication because it’s such a polarising issue you would never get any basic agreement about the basic facts and what should actually be communicated, and it would inevitably get bogged down in tedious arguments about upside down proxies etc.

  21. Tom Fuller Says:

    Hi Andrew,

    As usual, your comments are cogent and I agree with most of what you write. And, as usual, there are a couple of minor points where I slightly disagree.

    I think the Hockey Stick episode needs a fuller explanation than it has been given to date, and I say that as one who helped write a book about Climategate. I think that it highlighted a perfect storm in a way, where science, communications and policy all combined to a negative effect.

    Your point about general purpose and political blogs being a more attractive forum is I think quite true. But that has already been grasped by the likes of Mike Roddy at Revkin’s blog, Secular Animist, who infests Kevin Drum’s site and other acolytes who probably think Eli Rabett is a good guy. The territory has been staked out and anyone not from the Brigati Rossi who tries to comment there will get slammed.

    As for the information deficit issue, all of us risk life and limb, family and friend on a daily basis using the tools and technologies of modern life that we probably don’t thoroughly understand. Perhaps this is best memorialized by Elton John–‘And all the science, I don’t understand, it’s just my job five days a week.’ Kind of nonchalant for a rocket man.

    Later today I will be flying at 30,000 feet in a tube built of composites and metal, directed by a fly-by-wire network and powered by an array of engines sucking air into turbines in a method that I think most of my fellow passengers fail to fully understand.Most of them will look thoroughly bored as they wait to board.

    Finally, I don’t think that you need to persuade the outright skeptics. At the end of the day you really just need the following:

    1. You need to outnumber them, which you already do–but you’d better watch those numbers.
    2. You need to acknowledge your opponents fairly, honestly and with a modicum of respect, less this turn into a vendetta that lasts a century. This I see no sign of occurring, thanks in large part to people like Rabett and his breed.
    3.You need to listen to people like Paul Kelly and create a policy framework that embraces far more than climate change, so that you can build a Big Tent for policy makers.

    But those like Rabett that have run amok across the electronic landscape haven’t helped. They have operated as if they would never need allies, they have continually rejected parallel causes, they have left in the dust the other environmental causes which they falsely claimed gave them legitimacy and they have rejected any who would try to make common cause without drinking their Kool Aid.

  22. andrew adams Says:

    Hi Tom,

    Thanks for the reply and apologies in advance for another long response. First of all I think the point is worth making that there is a lot of agonising about the manner of the debate on climate change and how it’s gone wrong but actually it is no worse than on a lot of other issues where people have strong views, and actually better than some – compared with the debates on abortion (at least in the US) and Israel/Palestine for example it is positively genteel. Obviously there are two elements to the argument – firstly there is the purely scientific side, and here I think I’m in favour of strictly technical arguments, with strict moderation if necessary. Then there is the political side, and here I think we have to be realistic about the kind of debate we are going to get. I’m not saying there shouldn’t be limits to what’s acceptable – people should argue honestly, get their basic facts right, should not just dismiss those who disagree with them as “trolls” and should certainly not compare them to Nazis or paedophiles, but people on both sides have strong views and believe that the other is advocating actions (or inaction) which will have strong negative implications for themselves and/or or others and the planet in general and I think it inevitable and often excusable that harsh words will be exchanged, and let’s face it you can dish it out with the best of us at times ;) I’m going to have to disappoint you by saying that I am one of those who thinks that Eli is one of the good guys, I can’t comment on your other examples as I don’t read the blogs concerned.

    I think that answers point 2 of your three points, regarding the others I agree with point 1 and to an extent with point 3. I certainly accept that some policies which will help mitigate climate change will have wider benefits and it is right that we emphasise these, and as long as desirable policies get implemented it doesn’t really matter why this happens. But ultimately if we seriously want to combat climate change we will need to implement policies designed to combat climate change – the policies which will be acceptable to the skeptics for other reasons will not be suficient in themselves, and in some cases it might be necessary to implement them with more urgency than would otherwise be considered appropriate. It would be nice if there was some kind of compromise set of policies which was both acceptable to all sides and would actually be effective in mitigating AGW but I just don’t think there is.

    Finally, on the “information deficit” question you make a fair point. I think that all of us are happy to rely on a lot of things in life without feeling to need to understand how they work, and I think that in the case of climate change a lot of people are indeed content to trust the judgement of experts, and I don’t criticise them for that. But it is not always obviously apparent to people that our climate is changing in the same way that it is apparent that airplanes do actually fly, and skeptical arguments do make it into the media and they are often superficially plausible, so it doesn’t surprise me that some people do have doubts.

  23. thomaswfuller2 Says:

    Andrew, why did you quit blogging? You’re both good and intelligent.

  24. Paul Kelly Says:

    On Fuller’s point 3:

    My first thoughts about a shared goal framework came after reading an article by one of the early greats of climate science saying the solution to AGW will come from the solution to something else. I also read about a Prius hyper mileage club in California. Members are evenly divided among climate concerned, gear heads and cheapskates. Different reasons, same goal.

    Is implementation of shared goal the whole solution? No. It is, as Bart notes, a means to an end. Shared goal is the proverbial step in the right direction.


    “We will need to implement policies designed to combat climate change – the policies which will be acceptable to the skeptics for other reasons will not be sufficient in themselves”

    This is disproved by events. For example, the climate science consensus is that mitigating short lived forcings is as important as mitigating long lived forcings. The most important short lived is carbon soot. Reducing carbon soot is a key climate mitigation policy. But there are other equally compelling reasons – other environmental concerns, health – to reduce carbon soot. On of the cosponsors of the Senate bill that addressed carbon soot was James Imhofe, climate denier extraordinaire. It is the wonder of shared goal.

  25. Tom Fuller Says:

    To follow on from Paul (Hi Paul), one commonly recognized tactic that the climate consensus has ignored is habituation. If you think back to past policy victories over entrenched opposition, it often starts with getting your foot in the door and gradually opening it wider.

    People were shocked and upset when they banned smoking in hospitals, airplanes and movie theaters. But they got used to it and accepted the logic grudgingly and accepted both incremental extensions of smoke free areas and the logical end points of smoking bans.

    But a lot of this was sold on the back of patient health in hospitals, litter in theaters and obscured vision and air quality on airplanes. Smokers accepted change based on effects on others, not because they suddenly changed their mind about the toxicity of the damn things.

    If you can cite three compelling reasons to reduce CO2 emissions it will have more impact than just citing climate change, a nebulous concept to most.

  26. Eli Rabett Says:

    The evidence showing that smoking causes harm to non-smokers was quite strong even 20 years ago, but the industry industriously hired the usual trolls (Heartland, Singer, etc) to muddy the waters and delay action. Foot in the door Eli’s ears.

    BTW, having read on this recently, one of the most depressing thoughts is that the smoke that wafts into the area around the smoker is more toxic than the smoke the smoker inhales through the filters and even through the tobacco which trap some of the nasties.

  27. BBD Says:


    The cigarette filter is an interesting thing. As a former smoker, I can attest that filters are an enabling technology. They make it easier to smoke more cigarettes a day. Smokers investigate this empirically during times of economic hardship when rolling tobacco is the only option.

  28. Tom Fuller Says:

    Sadly, the harm caused to non-smokers was inflated to suggest that the harm included cancer, which has never been demonstrated.This of course caused a total eclipse of the serious harm it does with regards to asthma, allergies, vision, etc.

    But that doesn’t remind anyone of anything, does it?

  29. Marco Says:

    Yes, Tom, your claim reminds us of something: experts in the field agreeing, but industry paying off thinktanks and selected scientists to create/sustain a controversy.

  30. Bart Says:

    The tobacco example shows, amongst other things, that measures to mitigate the negative effects were accepted only after the science was accepted by the public. Ie efforts to inform the public of the science is not in vain, but remains a necessary (though in itself insufficient) ingredient to have the public agree to measures in their long-term common (but against their short-term individual) interest.

  31. Tom Fuller Says:

    I disagree, Bart. The general public knew for a very long time that smoking was generally harmful and often fatal. Nobody was surprised to hear it caused cancer.

    In the U.S., at least, the narrative is far more complex.

  32. Marco Says:

    Nobody was surprised, many still think “I am not one of them”.

    Fun study here:

    It’s a well known psychological problem, likely even part of our genetic code: cognitive dissonance. Accepting the facts, but denying them when applied to yourself.

  33. Eli Rabett Says:

    Sorry Charlie, that is a tin of tuna

    The accumulated evidence on lung cancer and environmental tobacco smoke

    A K Hackshaw, M R Law, N J Wald

    BMJ VOLUME 315 18 OCTOBER 1997 980

    Main outcome measure: Relative risk of lung cancer in lifelong non­smokers according to whether the spouse currently smoked or had never smoked.
    Results: The excess risk of lung cancer was 24% (95% confidence interval 13% to 36%) in non­smokers who lived with a smoker (P < 0.001). Adjustment for the effects of bias (positive and negative) and dietary confounding had little overall effect; the adjusted excess risk was 26% (7% to 47%). The dose­ response relation of the risk of lung cancer with both the number of cigarettes smoked by the spouse and the duration of exposure was significant. The excess risk derived by linear extrapolation from that in smokers was 19%, similar to the direct estimate of 26%.
    Conclusion: The epidemiological and biochemical evidence on exposure to environmental tobacco smoke, with the supporting evidence of tobacco specific carcinogens in the blood and urine of non­smokers exposed to environmental tobacco smoke, provides compelling confirmation that breathing other people's tobacco smoke is a cause of lung cancer.

    That was 1997

    Here is a more recent study

    Count your fingers kids.

  34. Tom Fuller Says:

    interval 13% to 36%? Yeah, count your fingers.

  35. andrew adams Says:


    You might remember Bart’s excellent piece at Planet 3 where he argued why it is important to take action on long term problems.

    Your point about carbon soot doesn’t really contradict my argument – as I said, I agree we should accept that there are arguments other than mitigating climate change for some desirable policies and it’s right for us to stress those arguments.
    So lets reduce carbon soot and use whatever justification is necessary, but that is not in itself going to be sufficient to prevent AGW reaching dangerous levels – that can only be done by reducing CO2 emissions. Again there are arguments other than climate change for doing this but climate change makes the need more pressing and that is going to mean enacting policies which are going to be unpopular in some quarters.

  36. andrew adams Says:


    Many thanks for your kind words. I didn’t intend to stop blogging I kind of just fell out of the habit. I keep meaning to get back to it, so will try to pul my finger out.

  37. Eli Rabett Says:

    Mr. Fuller reminds us that 0.03% of CO2 in the atmosphere is so small it cannot possibly have an effect, but yes, environmental smoke causes lung cancer, it may not be the major cause of death and disease from smoking, but it is one. FWIW, only about 25 % of deaths from smoking are from lung cancer

    Worldwide burden of disease from exposure to second-hand smoke: a retrospective analysis of data from 192 countries Mattias Öberg, Maritta S Jaakkola, Alistair Woodward, Armando Peruga, Annette Prüss-Ustün,

    The Lancet Volume 377, Issue 9760, 8–14 January 2011, Pages 139–146

    Worldwide, 40% of children, 33% of male non-smokers, and 35% of female non-smokers were exposed to second-hand smoke in 2004. This exposure was estimated to have caused 379 000 deaths from ischaemic heart disease, 165 000 from lower respiratory infections, 36 900 from asthma, and 21 400 from lung cancer. 603 000 deaths were attributable to second-hand smoke in 2004, which was about 1·0% of worldwide mortality. 47% of deaths from second-hand smoke occurred in women, 28% in children, and 26% in men. DALYs lost because of exposure to second-hand smoke amounted to 10·9 million, which was about 0·7% of total worldwide burden of diseases in DALYs in 2004. 61% of DALYs were in children. The largest disease burdens were from lower respiratory infections in children younger than 5 years (5 939 000), ischaemic heart disease in adults (2 836 000), and asthma in adults (1 246 000) and children (651 000).

  38. Tom Fuller Says:

    It is because second-hand smoke is a real and serious health problem that it is important not to throw in garbage statistics about it causing lung cancer. It destroys the credibility of those making serious claims. But then, for some, credibility is not really an issue.

  39. Eli Rabett Says:

    Mr. Fuller, those are not garbage statistics and you are seriously harming what little credibility you have left. The facts are, that among other harms, environmental tobacco smoke contains potent carcinogens and that we have excellent evidence that inhalation of these carcinogens, causes, guess what? lung cancer.

  40. Tom Fuller Says:

    Lord save us all from trolls with bogus stats and faulty studies. Smoking kills smokers. Smoking harms non-smokers. Not with minor complaints, not with simple maladies. It causes problems and exacerbates existing ones. But second hand smoke has not been linked to lung cancer. Despite the fervid wishes of so many.

    However, second-hand smoke has been linked to sea level rise.

  41. Marco Says:

    Let’s see, we have
    1. chemical analysis showing “second-hand” smoke containing known carcinogens, as tested in animal studies
    2. animal studies directly showing increased risk of lung cancer when exposed to “second-hand” smoke
    3. epidemiological studies showing increased prevalence of lung cancer amongst those exposed to “second-hand” smoke. The Rabett was nice enough to point to two of those studies.

    Tom’s response?
    Citing the scientific literature? Must be a troll! Oh, and those studies are faulty and filled with bogus stats. There, there’s my evidence they are faulty and bogus stats: I just said so.

    I could add a few more papers to the list of studies that show increased risk of lung cancer due to second-hand smoke, but I’m sure Tom’s response will remain the same: denial of the evidence.

  42. Bart Says:

    Is it just me or is it a little ironic that we’re discussing the harms of second hand smoke on the Vahrenholt thread whole discussing Vahrenholt on the open thread?

  43. Eli Rabett Says:

    This is the INTERNET Bart.

  44. Bart Says:

    You may be old, but I’m old-fashioned… ;-)

  45. BBD Says:

    Reflexive contrarianism is a nasty condition. It is invariably fatal (to credibility).

  46. willard (@nevaudit) Says:

    On the June 18, 2012 at 23:44, Eli posts statistics.

    On the June 19, 2012 at 04:10, those statistics are inferred to be garbage.

    It would be interesting to see the raw model data for that speedy inference.

  47. Christopher McDaniel Says:

    “based on confusing short term variability with the long term underlying trend.” You say this, and yet, every single expert has maintained that 15 years or more would constitute enough time as to indicate a devastating flaw in the alarmist arguments. Now, the MET has decided that 20 years is sufficient. Why the constant changes to lengths. Will they change again once we hit 20 years of cooling?

  48. Marco Says:

    Christopher, stop listening to fake experts. The *real* experts have for years already pointed out that you need many years. Santer et al (2011) put it at *at least* 17 years.

    And still, when cherry picking the start point as Rose did (well, somebody probably did it *for* him), the trend is positive.

  49. thomaswfuller2 Says:

    15 years is certainly sufficient to flag up potential problems and focus our attention on model performance. However, there is no upper limit on how much data you would ideally want to have before making an important decision.

  50. Ian H Says:

    Science is conflicted with regard to the role of expertise.

    On the one hand the philosophy of science urges us to ignore appeals to authority and evaluate each argument on merit. This philosophy is captured by the motto of the royal society “nullius in verba” – don’t take anyone’s word for anything.

    On the other hand the reality of science today demands a very high level of specialisation and expertise and in practical terms one would be extremely foolish to argue with an expert in their area of specialisation unless you are a specialist in that area yourself.

    How can we reconcile these two things?

    The way I see it it is quite reasonable for us as a practical matter to trust experts most of the time for the purely practical reason that none of us have the time to do anything else. But the philosophy of science hasn’t gone away. We retain the right to demand convincing evidence or to look at and evaluate the evidence ourselves should we ever lose faith that the experts are behaving as rational scientists should. Indeed this isn’t just a right – as I see it, it is an obligation.

    To me climate scientists are not behaving or communicating in a scientific fashion. Scientists make reserved statements and are careful to say only things that are supported by evidence. They clearly express the degree of uncertainty and the limits to their knowledge and understanding. Climate scientists have departed so far from this norm that I don’t recognise scientific behaviour in them any more. They appear to be engaging more in advocacy than in science, they argue backwards from conclusions cherry picking the data rather than letting all the evidence speak for itself; they respond with nasty ad hominems when asked reasonable questions. I see statistics being abused; data being hidden; data being manipulated; the peer review process being subverted.

    As a scientist myself I have a right to demand an explanation or evidence that I personally find convincing and to refuse to take anyone’s word for anything. Nullius in verba still applies. I very seldom invoke this right. But I do retain this right. Nobody can demand that I accept what they say simply because they claim to be “expert” in some respect. The choice as to whether and to what extent I should defer to someone’s claimed expertise remains mine and mine alone.

    Because I have lost faith that the science in this area has been done according to proper scientific principles I have invoked my right to be personally convinced by evidence in this area. As someone whose expertise lies elsewhere I agree this is highly inefficient. It would be much easier for me to not have to think about the climate – I have much more interesting things I would rather spend my time thinking about. But as I don’t trust what is going on in this area, I would be quite wrong to do so.

    I remain a sceptic. I am still not convinced.

  51. Marco Says:

    Ian H,

    “Scientists make reserved statements and are careful to say only things that are supported by evidence”.

    That’s quite a bold statement to make, when you later claim about climate scientists that…

    “they argue backwards from conclusions cherry picking the data rather than letting all the evidence speak for itself; they respond with nasty ad hominems when asked reasonable questions. I see statistics being abused; data being hidden; data being manipulated; the peer review process being subverted.”

    …which simply is not supported by the evidence!

    Oh, I am sure you can find the occasional example of a climate scientist doing some of the things you claim. I am also sure, however, that quite a few of the *claims* that certain climate scientists have done something nefarious are actually the result of cherry picking data, hiding data and manipulating data.

    Here’s a good example of the latter:
    A good example of manipulating/hiding data by cutting out part of an e-mail that contradicts the desired narrative.

    A little later
    we see how McIntyre created a false narrative by cherry picking some e-mails and ignoring others.

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

%d bloggers like this: