How to be a real sceptic

Can someone be productively sceptical? Of course. Firstly, one needs to be aware that scepticism about whether a particular point has been made convincingly is not the same as assuming that the converse must therefore true. Sometimes scientists just don’t use the best arguments they could (particularly if they are a little out of their field of expertise) and these points can, and should, be challenged. One example would be the use of an incorrect ‘correlation implies causation’ argument. For instance, the strong correlation of CO2 and temperature in the Antarctic ice core records does not in and of itself imply that CO2 has a radiative impact on climate. However, additional analyses that look at the factors controlling temperature during the ice ages give strong grounds for believing that CO2 does play an important role. Therefore while the use of the correlation argument alone is wrong, the converse of the conclusion is not necessarily true.

Secondly, it helps to have done the homework. It is highly unlikely (though not impossible) that the sceptical point in question has not already been raised in the literature and at meetings. If a particular point has been argued to death previously and people have moved on (either because it was resolved, moot or simply from boredom), there is little point bringing it up again unless there is something new to talk about. Obviously, a good summary of how the point was dealt with can be educational though. Arguments about whether the current CO2 rise is caused by human activity fall clearly into this category.

Thirdly, scepticism has to be applied uniformly. Absolute credence in one obscure publication while distrusting mountains of ‘mainstream’ papers is a sure sign of cherry picking data to support an agenda, not clear-thinking scepticism. Not all papers get the peer review they deserve (or require) and the literature has many examples of dubious logic and unsupported interpretation. Sometimes this becomes very clear (for instance, the Soon and Baliunas saga at Climate Research), and sometimes it goes uncommented upon. But what about Galileo? Wasn’t he an obscure scientist persecuted by an entrenched mainstream? Yes, but Galileo is celebrated today because he was correct, not because he was persecuted. If an idea is right, it will be supported by additional evidence and will lead to successful predictions – at which point it will likely be accepted. The ‘Galileo’ defence (and its corollary the ‘establishment conspiracy’) are usually a sign that the additional evidence and the successful predictions are lacking.

Finally, it should be understood that constructive scepticism is a mainstay of the scientific method. The goal of science is to come closer to a comprehensive picture of how the real world works, with scepticism essential to toughening up scientific ideas, though alone, it is insufficient to move understanding forward. It isn’t essential that every true sceptic have an alternative theory ready to go, but they should bear in mind that our picture of how the world works, though incomplete, rests on many different foundations. If it sometimes seems that the scientific consensus is resistant to new ideas, it is because that consensus has already been tested in many ways and yet still stands.

Much of what passes for ‘debate’ on climate change in the popular media, is often framed as the ‘scientific consensus’ vs. the ‘sceptics’. A close examination of these arguments (for instance, as outlined in a recent Wall Street Journal editorial) doesn’t reveal much that could be described as true scepticism since they often use the fallacious reasoning that we discuss above. However, since scepticism has a (justifiably) long and noble tradition in science, the framing device is quite powerful (despite the lack of connection with any actual scepticism). As with the intelligent design controversy, agenda-driven opposition has often managed to cloak its contrarianism with the mantle of scepticism. So, while many contrarians pay lip service to the legacy of Russell (or even Pyrrho), forgive me if I remain a little sceptical…

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210 comments on this post.
  1. Don Flood:

    It must be admitted (based upon the evidence) that most scientists are atheist and/or agnostic (with ‘weak atheism’ being an extension of agnosticism):

    As with the ‘debate’ on evolution, I think it is clear (or, at least ‘suspect’) why many people do not take global warming seriously. Of course, only experts in psychology, sociology, anthropology, etc., can know for sure. Perhaps more research needs to be conducted in this area!

  2. Barton Paul Levenson:

    Re #1 — I’d like to point out that I am a born-again Christian, and I have a physics degree, and I support the scientific consensus on both global warming and evolution. I can sympathize with Mr. Flood’s reaction to a piece quoting Bertrand Russell and the suspicion that “skepticism” of the anti-religious type is, if not directly mentioned here, at least implied. But I honestly don’t think this article went over the line. Please, let’s not turn this into one of the many thousands of pro- and con- theism boards. We could get a thousand comments in which no one ever convinces anyone else. This site is about climate change, the evidence for it and the opposition to it, and I really feel we ought to stick with that. There are many other venues for debating theism v. atheism.

    [Response:Indeed. This post has nothing to do with that debate – gavin]

  3. Mark A. York:

    Science doesn’t even ask that question.

  4. Mark Frank:

    Most of the sceptics I know would object to “we can substitute in the IPCC for ‘experts’ in the quote”. It is not just the number and eruditeness of the experts that matter, but the culture and organisation in which they operate. It is this issue which which keeps me wondering.

    [Response:You are certainly right that a particular group of scientists may not be representative of the actual position of experts at large. For example, one would rightly be skeptical of claims by tobacco-industry scientists about the safey of cigarrettes, no matter how many of them there are. It happens, though, that many many scientists that work on climate (myself, for example) are not part of the IPCC working groups, yet consider the IPCC documents to be good representations of the current state of knowledge on climate change. -eric]

    [Response: I’m a first-time participant as a lead author in the IPCC process. I’ve been to three author meetings so far, and I’ve found that there is a culture of very open and critical discussion of the science, with no top-down interference whatsoever. We write what we agree on after thorough discussion. I asked around the room amongst the authors of our chapter who has been a lead author before, and it turns out that it’s the first time for all of us. None of us feels any need to stick to some “party line” or defend what the IPCC (i.e. a different group of people) wrote in the last report. The idea promoted by some sceptics that the IPCC is some kind of closed-shop organisation is completely wrong. The IPCC is simply a process where a large bunch of scientists, chosen for their demonstrated expertise based on their publication record, get together to assess the published scientific literature as best as they can. (And that without pay in their free time, i.e. sacrificing a lot of nights and weekends.) -Stefan]

  5. Tony Noerpel:

    Re #4 Naomi Oreskes wrote an article in Science which reported on the papers about global warming published between 1993 and 2003. She found no papers contradicting the view that anthropogenic global warming is underway. I don’t know if her study was exhastive or accurate, but if true, then those authors would constitute a groupof “experts”. I don’t know why papers by contrarians like John Christy may have been excluded.

  6. Tony Noerpel:

    Oreskes “The scientific consensus on climate change”, Science 306, 5702 #686, 2004

  7. Don:

    Small point, Galileo was hardly obscure. The civil and military engineering products of his science made him an important figure during the early decades of the 17th century in Italy and beyond. Although sentenced to house arrest for the Dialogues, his persecution was not nearly as painful as that of Gioradano Bruno some 30 years earlier. Bruno was burned at the stake for intellectually similar defiance of authority to that of G. While we remember Bruno for his persecution, his philosophy cum science was actually substantial. The different treatment of B from G illustrates how rapidly science was being integrated into society by Galileo’s time.
    Apropos the comments of the fundamentalist Christian commentator, your reasoning that G is celebrated today because he was correct, not because of his persecution or contrarian stance, is pertinent. Your reasoning is also pertinent generally to discussions with non scientists about how science works and why. Your reasoning applies perfectly to science’s appreciation of Newton. Newton was devout and professed piety. He thought and wrote hugely about the relationship of his work to the designs of the Creator. However, he is celebrated today because he gave us the fundamentals of physics. The contributions to knowledge of his devotion and piety are to scholarship about the divorce of science from Christianity. Newton’s science cum religion continues to be meat for philosophers, historians and sociologists of science; it made no contribution to religion or to religious philosophy, the most important of which doesn’t care much about science. Were it only for his religious writing, Newton would be no more than an historical curiosity. His agonies over doing physics to know the “mind of the Creator” illustrates the death throws of Scholasticism, when the Siamese twins objective and subjective were separated. By the time of Newton, science was the objective. Religion inherited the “subjective”.

  8. Steve Bloom:

    Re #5 (TN): I believe Christy’s papers (in recent years, anyway) have been limited to the UAH satellite stuff, discussed on this site at length recently. He has certainly had no problem getting them published, although their subject matter can’t be called skeptical in a strict sense (but have been used as ammunition by skeptics). So far as I’m aware, Christy himself hasn’t written anything that can be called contrarian. His co-author Roy Spencer is a different story, but Spencer’s skeptical/contrarian material has been written for the popular press rather than peer-reviewed publications (which is what Oreskes surveyed).

    Broadly speaking, legitimate papers that support skeptic positions don’t seem to have a problem finding a publisher in the peer-reviewed literature. Certainly some are rejected, but then lots of papers get rejected. As Gavin noted with regard to the Soon/Baliunas fiasco, sometimes the peer-reviewed press goes a bit too far in allowing skeptical/contrarian views.

  9. Tony Noerpel:

    So if we restrict ourselves to peer-reviewed journals then certainly we can construct a body of Bertrand Russell experts. Further, I assume they all agree on anthropogenic global warming as per Oreskes’ research. Thus the contrarian view on anthropogenic global warming cannot be held to be certain. Was Oreskes’ result correct?

    [Response: The Oreskes result doesn’t really tell you anything you wouldn’t have already picked up by going to a big meeting like AGU in San Francisco or EGU in Vienna. Out of the thousands of people talking about various aspects of climate change, the number of contrarians could be counted on one hand. Even if these few were prodigious writers of peer reviewed papers they still might not come up in a survey such as Oreskes. – gavin]

  10. Steve Bloom:

    Other than to point out that there is actually a wide range of skeptic/contrarian views, those conclusions seem fair. Of course there are skeptics/contrarians who dispute Oreskes’ findings, but that is no surprise.

  11. Francis MASSEN:

    I would be better of if more of the climate scientists were more sober and less alarming in their statements. Everybody has ample examples that alarmism (being justified or not) pays back well in publicity and funding. Non-alarmism does not. So we really have here a soft spot that in my opnion is more extreme in politically entangled climatology than for instance in plain engineering. We should just reflect on this: what if every major climate research result from the last 50 years (being it an impending ice age or an overheating planet) had been directly transformed into politically action? Would these actions all have been wise? I think an intelligent “wait and see, let the dust settle down and than act” behaviour is good scepticism, not boring “contrarianism”.

    [Response: I don’t know of any example where ‘alarmism’ has been good for funding as opposed to media attention (and even then, that is the exception). I have served on many program panels where money is given out and in no case was money given because a proposal was ‘alarmist’. In general, the money goes to the best thought out, interesting and tractable proposals, and since there are more of those than can be funded, it is indeed rare that poor proposals, even in an exciting area get funded. I don’t think anyone advocates significant policy action based on individual studies or results – it is the weight of evidence from hundreds of studies that have formed the basis of the IPCC conculsions and that is what is propelling policy action, not the paper-de-jour in this weeks Nature or Science. – gavin]

  12. Lynn Vincentnathan:

    I think your distinction between expert and layperson (non-expert) is good. However, with Pascal, laypeople have a better way of deciding what practical thing to do with the knowledge (at its various levels of acceptance) scientists give us.

    Because I don’t know enough science to debate contrarians scientifically, I usually fall back on: Suppose the mainstream climate scientists are wrong & the contrarians right, and we act as if the scientists are right, then we have nothing to lose & something to gain in terms of reducing other environmental harms (acid rain, local pollution), resource depletion, and increasing national security (re oil wars & protection), and lots of money to save from energy/resource efficiency & conservation, and increasing from alternative energy.

    On the other hand, if the climate scientists are right about AGW happening, and the contrarians are wrong, and we act as if AGW is not happening, then not only will we lose all those other benefits, but we will allow the world to sink into great catastrophe (greater than you may think, when we figure how people may start turning nasty against each other as their material lives deteriorate – Katrina gave us a microcosm of that).

    Pyrrho should have figured out whether his teacher might die or be harmed, if he did not pull him out. And since we can never be totally sure about anything (‘cept death & taxes), he couldn’t have known beforehand he’d be unsuccessful. At least he could have stayed and given company to the man. OTOH, maybe he didn’t like his teacher, the way contrarians seem to (perhaps at a subconscious level) hate the world, or there was a big test coming up & he was ill prepared for it.

    BTW, science only strengthens my belief in God, mainly because my premise (faith, not evidence-based) is in God, so that everything in the world only wows me more about God’s greatness, including evolution. I find intelligent design offensive in its reduction of God to a David Copperfield magician (a god of man’s image, rather than beyond our comprehension, and allowing God to reveal himself). Perhaps God may be offended by ID, too. The way I see it is everything is a miracle. Some miracles have scientific explanations, and some do not….yet. And the fact that we are destroying the earth through AGW is proof to me God gave us free will. (What was God thinking, anyway, when gave us free will to us bratty children?)

  13. Hans Erren:

    My skepticism is about fact finding, so far I found:

    1) Business as usual is more likely the SRES A1T scenario, although the next ten years have an absurd emission growth.
    2) I have not seen evidence for carbon sink saturation, CO2 doubling is unlikely this century.
    3) Transient CO2 sensitivity is low.
    4) Warming is net beneficial in the colder areas
    5) Desertification is caused locally by deforestation and mismanagement.
    6) The polar bear population is increasing. Climate change is not likely only good for bad animals and bad for good animals
    7) The glaciers are disappearing, so what? It takes 3000 years to melt Greenland
    8) Educated women have less children

    Action points:
    Stop real pollution, increase efficiency, fight corruption, educate girls.

  14. Roger Albin:

    To give credit where credit is due, the Bertrand Russell analysis quoted above is essentially a gloss of Hume’s epistemology, the position usually termed mitigated skepticism.

    [Response: Thanks – gavin]

  15. Anthony Kendall:

    I’m reviewing Tom Bethell’s political book “The Politically Incorrect Guide to Science” on my blog, and I’ve found that the cherry picking aspect of “skepticism” is definitely at work. His signature tactic throughout his book is his willingness to dismiss the efforts of thousands of probably very brilliant individuals because someone sometime publised a paper that disagrees.

    Thank you for the excellent piece on skepticism, and the quote from Russell. This will be a post I refer back to often.

  16. Andrew Dodds:

    Re: 11

    It is extremely hard to find genuine climate scientists who ARE alarmist; wheras it is of course easy to find ‘skeptics’ who claim that all AGW research is alarmist, and that this is essential for funding.

    On the subject of getting rich and famous, Bjorn Lomborg and Michael Critchon have done very well out of global warming, of course.

    Of course, the idea that there was some major consensus in the 1970s that an ice age was coming on in the immediate future is simply an urban legend. Any real skeptic – i.e. one who was both honest and informed – would not try that one.

    I would actually cite things like Near Earth Asteroid research and Supervolcano research as far stronger examples, but even in this case it is the journalism that is ‘alarmist’, far more so than any of the scientists.

  17. Barton Paul Levenson:

    Re #7 — We theists do not consider our beliefs as being somehow intrinsically “subjective.” This board is supposed to be for discussing climate change, but by God if people diss my beliefs I WILL respond to them.

    [Response: Any further comments on religion rather than science will be removed as being off topic. – gavin]

  18. Chris Reed:

    Re #4 Mark Frank. For what it’s worth: Up until about February this year I was sceptical. I had found that in the midst of conflicting views in the media and on the net I had only one option: To learn the science as well as I could and form my own opinion.

    What I now see is that we have a good general idea of what is where we are and the direction we’re headed. Not a detailed map. Much of what I had previously thought was doubt about the direction, (or indeed whether we’re ‘moving’ at all!) is actually inflation of doubts about what the ‘map’ actually looks like. I now have no doubts that we’re warming the planet primarily by CO2 emissions (but not exclusively) and consequently disturbing our climate.

    The only doubts I have are about what is actually going to happen in detail. But that’s always the case when considering the future. However I remain ‘very concerned’ about what we’ve started.

    My advice: If in doubt; learn! Arguments such as the ‘cultural’ one, and the ‘it’s all hype to secure funding’ are, in my opinion, lazy. The evidence and arguments are out there and laid bare. But learning takes hard work. And those purveying the ‘culture/hype’ angle seem to me to be taking advantage of the fact that most people won’t learn the science.

  19. Lynn Vincentnathan:

    RE #11, I completely disagree that scientists are alarmists. It’s their findings that are alarming, and it’s almost surreal that scientists present them as they would any other findings — in a mundane, erudite way with the usual caveats. Just read some of those boring science journal articles (not the editorials, but the ones with abstracts and data).

    We lay people should be alarmed by AGW. Why aren’t more of us alarmed? That’s a real bafflement.

    When I first came to realize we may be putting our life world at great risk from AGW back in 1990 (5 years before the 1st studies had reached .05 significance on GW), I thought all I needed to do was reduce my own GHGs (I was willing to sacrifice to do so, since the threat certainly warranted sacrifice in my mind), and simply tell others about the problem, and they’d follow suit. Then I could get back to my regular life.

    But it didn’t work out that way. Instead of sacrifice, I found myself saving lots of money by reducing GHGs, without lowering our living standard. The real shocker, however, was that many people seem to be totally recalcitrant about acknowledging (much less doing anything about) the dangers & harms we’re facing. They don’t want to believe it, no matter how much evidence pours in, or they socially construct it as just like any other problem (to be ignored & left to the problem-fixers).

    I would hope the public & politicians & contrarians sober up, roll up their sleeves, and start saving money by reducing GHGs. Otherwise, I’m beginning to think people are crazy or something.

  20. John F. Bradley:

    Regarding the issue of whether some “mainstream” scientists are “alarmist” in their discussions of global warming, it is well to remember that, in any controversy, scientific or otherwise, there will be extremists at both ends of the spectrum. While the reality of global warming is well established, there is ample room for disagreement about just how seriously it will impact the world. Those who anticipate the most extremely dire consequences are the ones most inclined to be alarmist on this issue.

    Also, it should be remembered that scientists differ in terms of temperament, and in terms of their feelings about the duty to influence public opinion and public policy. Some scientists can readily accept that the people, in a democracy, have the ultimate right to decide whether we should take precautionary action, or whether the risk of doing nothing about global warming is an “acceptable risk”. Other scientists may feel that it is so essential to make sure that the public decides this issue “correctly”, that hyperbolic tactics like inflammatory rhetoric, and exaggeration of the scope of the true danger are morally acceptable.

    [Response: Who are these people? Give me an example of a scientist using ‘inflammatory rhetoric’ to exaggerate the true danger if you can. There may be some cases, but the accusations of ‘alarmism’ come much more frequently than any actual incidence…. – gavin]

  21. Harry Pollard:

    Perhaps the Trenberth Press Conference in which the connection of hurricane frequency and intensity to GW was affirmed is an example of “alarmism”.

    The Press Conference was annouonced as “Experts to warn global warming likely to continue
    spurring more outbreaks of intense hurricane activity”.

    Needless to say, this and other media exposure made for scary headlines directly connecting hurricanes to GW.

    As Chris Landsea was to say:

    “I found it a bit perplexing that the participants in the Harvard press conference had come to the conclusion that global warming was impacting hurricane activity today. To my knowledge, none of the participants in that press conference had performed any research on hurricane variability, nor were they reporting on any new work in the field. All previous and current research in the area of hurricane variability has shown no reliable, long-term trend up in the frequency or intensity of tropical cyclones, either in the Atlantic or any other basin. The IPCC assessments in 1995 and 2001 also concluded that there was no global warming signal found in the hurricane record.”

    I regard the IPCC contention as an hypothesis. Crucial to any hypothesis is testing. I don’t think that the IPCC is an adequate vehicle for testing their hypothesis. In fact, I have found little or no evidence against the GW hypothesis on the IPCC website.

    So, one must go outside the IPCC to find any adequate testing of the hypothesis.

    Yet, anything outside the IPCC is considered “contrarian”. While paying lipservice to scepticism – the necessary part of science – in fact, anything outside the completely surrounded truth is given short shrift.

    With Landsea out of the way, I’ll offer my own hypothesis. The big push as we move toward the next Report will be to link hurricanes and GW in the minds of the public.

    [Response: We don’t need to get into specifics (but see our previous post on this subject) but linking hurricane intensity to sea surface temperatures has a strong theoretical (Emanuel, 1987; 2005), modelling (Knutson et al, 2004) and observational (Webster et al, 2005) basis, and so it can hardly be ‘alarmist’ to discuss it. It is true that the attribution of recent trends in intensity has not (yet) been made, but it is a valid subject for research and discussion. ‘Alarmist’ is defined as ‘a person who alarms others needlessly’; yelling ‘fire’ in a crowded theater when there is no such fire is clearly alarmist, pointing out an actual plume of smoke is not. – gavin]

  22. Michael Tobis:

    Regarding the use of the word “alarmist”, I would like to concede that there is some need to identify a position that is more alarmed than is the consensus.

    For one thing, I’d like someplace to hang my own hat.

    More important, though, is the absolute urgency and necessity of comunicating to the public that the IPCC reports represent a median position, not an extreme.

    The scientific discussion is misframed in the press, in the public mind and in the policy sector, as being between the consensus position and the “skeptics” who are so confident that nothing of consequence is at stake in anthropogenic climate change that they feel comfortable advocating an essentially trivial policy repsonse to it.

    At least equal weight should be given to scenarios which are worse than the consensus as to those which are more benign than the consensus. “Skeptics” is a misnomer for the latter group as much as “alarmists” is a misnomer for the former, but as I argued with little success here exactly a year ago, “global warming” is a misnomer as well.

    It is a shame to let politically adept people with preconceived agendas choose names so as to confuse the discussion, but on the other hand it’s better to have names for things than no names at all. This is called framing the debate, and indeed in at least that sense we’ve been framed.

    Anyway, please let’s not ignore the possibility of worse-than-consensus scenarios!

  23. Lynn Vincentnathan:

    Re #22, I’m with you, Michael. We need to get some environmentalists & victims (potenital or actual) of AGW in on the larger debate — people who are SKEPTICAL that the scientists are not telling us the worse, or don’t really know yet; people who don’t relish maintaining a “wait-and-see, do-nothng policy.” It is really too narrow a debate between moderate science and extremist “know-nothing” contrarians.

    However, I’m glad this site is here to propound & discuss the mainstream science on AGW.

    We just need to be aware that there are other views that may or may not be as bonkers as contrarian views, way on the other side of the debate (to which environmentalists & worry warts are not invited). The view that things might become much worse than what scientists can tell us with certainty right now. The view of people who expect the worse (& strive to avert it in “no regrets” ways) and hope for the best (that the contrarians are actually right).

    Why is this such a ridiculous position in the mind of skeptics, contrarians, the media, and our government? Do I smell…..?

  24. Pat Neuman:

    NYC indymedia article and comment…
    Alarmist or not alarmist. Helpful or not helpful?


    NASA: “The observed rapid warming thus gives urgency”

    An important message from NASA

    By pat neuman

    The observed rapid warming gives more than just an “urgency to discussions” …, it gives urgency to reduce greenhouse gas emissions as much as we can.

    “Recent warming coincides with rapid growth of human-made greenhouse gases. Climate models show that the rate of warming is consistent with expectations (5). The observed rapid warming thus gives urgency to discussions about how to slow greenhouse gas emissions (6)”.

    By pat neuman


    Polar bear family tree – researched by NWF

    Dec 19, 2005 09:47AM EST
    by Pat Neuman
    Related science on climate change

    National Wildlife Federation (NWF)- Bear family tree

    Snips – polar bear

    There are only eight species of bear living in the world today.

    All eight species have a common ancestor, Ursavus, that lived more
    than 20 million years ago.

    The Ursavus family line split into two subfamilies of what are
    considered ancestral bear-dogs: the Ailuropodinae (which ultimately
    evolved into the giant panda (Ailuropoda melanoleuca) that lives in
    China today) and the Agriotherium (which ultimately evolved into the
    Ursidae lineage).

    About 15 million years ago, Ursidae diverged into two new lineages:
    the Tremarctinae, known as short-faced bears; and the Ursinae, known
    as true bears.

    Ursinae gave rise to the six other bear species that exist in the
    world today. About 3.5 million years ago, early Ursine bears began
    migrating to North America by way of the Bering Land Bridge. These
    bears evolved into the American black bear (Ursus americanus).

    The brown or grizzly bear (Ursus arctos) began to evolve 1.6 million
    years ago. Brown bears were once found throughout Europe and Asia
    and eventually wandered into North America, following the same route
    taken by ancestors of the black bear.

    Scientists believe that the brown bear lineage split over 300,000
    years ago to form the polar bear (Ursus maritimus), theorizing that
    a group of early brown bears became isolated in colder regions and
    ultimately adapted to life on ice.

    National Wildlife Federation (NWF) link at:

    What we choose to do about how we use energy resources will have consequences, some of them unforeseen.

  25. Liisa Antilla:

    RE: Comment within #8: “So far as I’m aware, [John] Christy himself hasn’t written anything that can be called contrarian”.

    In response I’d like to point out a few published comments of John R. Christy, University of Alabama in Huntsville. While these are not taken from peer-reviewed literature, they are insightful nonetheless:

    “[N]umerous studies indicate the present biosphere is being invigorated by the human-induced rise of CO2. In and of itself, therefore, the increasing concentration of CO2 does not pose a toxic risk to the planet. … CO2 is not a pollutant”.

    (May 13 2003) John R. Christy, Written Testimony. U. S. House Committee on Resources; Kyoto Global Warming Treaty’s Impact on Ohio’s Coal Dependent Communities.

    “Has human activity been responsible for some of the last century’s temperature rise? The IPCC 2001 claims the following:

    There is new and stronger evidence that most of the warming observed over the past 50 years is attributable to human factors.

    Note carefully what the preceding IPCC quote actually says. The evidence is “new and stronger”. But is this evidence truly ‘convincing’ or ‘beyond doubt’ or ‘stronger than a DNA test?’ The evidence is described only as “newer and stronger” and hides the fact that uncertainties and inconsistencies are not only still present but in some cases growing.

    The alarmist media reports … become the source of downstream hysteria promoted by those with extreme environmental agendas. Such pronouncements by ideological environmentalists that the globe’s weather is worsening are actually false.

    The types of bad weather people really care about are not changing enough to notice. ”

    (2002) John R. Christy. “The global warming fiasco”. In: Competitive Enterprise Institute/Ronald Bailey (Ed.) Global Warming and Other Eco-Myths: How the Environmental Movement Uses False Science to Scare Us to Death. Roseville, CA: Prima.

  26. CapitalistImperialistPig:

    You say: “Finally, it should be understood that constructive scepticism is a mainstay of the scientific method.” The word constructive is extraneous. Constructive and destructive criticism both play crucial roles and I think a look at the historical record will show that the destructive version was usually more important. New ideas kill off old when the old are shown to be unsupportable.

    Additionally, you make the point that few climate scientists could fairly be called alarmists, and that fits my experience too, but the same is not true of the many political groups who want to wield these results as weapons against various entrenched interests. Fairly or unfairly, climate scientists are better known for the views of their ostensible political supporters than for their own.

    Finally, I would like to discourage the rather juvenile practice of referring to sceptics as “septics.” It damages your credibility more than theirs.

    [Response: I have the trademark on that. And I think its a good idea. But you’ve misunderstood. No-one is labelling genuine skeptics as septics. We/I am labelling those who are not skeptics, but who have an irrational and prejudiced disbelief against GW. Milloy for example. They need a label – what would you propose? – William]

  27. Mark Frank:

    Re #18 – Chris thanks for responding. I have been learning about this topic for about 5 years now (as a part-time hobby – so very far from expert). I am convinced that there is a degree of warming caused by anthropological introduction of greenhouse gases. But I am not at all sure how much warming, what the consequences will be, or what is the appropriate response.

    I also believe it is vital that the IPCC not only operate an open culture – but that it make a bigger effort to be perceived as open. Sceptical opinions should be welcomed, taken seriously, and answered (politely)in a way that is accessible (they are even more guilty of course). Every reported failure of openness should be treated as private organisation treates a complaint. Handled well, complaints are great opporunities for improving service and customer relationships. Seen this way the Barton committee is an opportunity, not a threat.

    These are onerous requirements but we are talking about a process and institution with massive consequences and surely we can find the resources. It doesn’t matter how good the science is if it doesn’t have the appropriate communications structure to support it.

    This web site is a great contribution but it is manned by volunteers in their spare time. It is too important for that. And a brief glance at climateaudit will give examples of sceptical postings that are within the comment policy that somehow don’t get posted on to this site. These are no doubt accidents – but that doesn’t matter – a little bit more damage has been done to the credibility of the process.

  28. amazingdrx:

    Why the urgency to prove that global climate change is substantially a result of fossil fuel combustion gases? Russell in fact consistently argued in his work that very few if any statments that say something about the real world can be proven.

    Does one need to prove that a meteorite will not crush one’s car before driving to work?

    Global climate disaster is not the only reason to shift from fossil and nuclear power to green energy. It is one of many.

    Sound familar?

    The existence of the Iraqi WMDs was not the only reason to invade Iraq, even when it was disproven, it did not invalidate the many other reasons for the war. (those other reasons can ALL be defeated separately,hehey).

    So what is the answer to the question: Does human combustion of fossil fuels signifigantly contribute to global climate change? Probably, and it constitutes enough probability that along with the other reasons to replace fossil fuel combustion, it tends to indicate that the shift to renewable energy is worth pursuing.

    Just as it is probably worth going to work and ignoring the possibility of a meteor strike on one’s car.

    This is the same false dilemna behind creationism versus evolution. The creationists claim that evolution is “just a theory”. That it can’t be proven, and therefore should not be taught in schools.

    So the argument goes, unless evolution can be proven, it should not be taught. Furthermore, since creationism is supported by the bible, an infallible text constituting the word of god, it should be taught

    But of course no scientific theory can be proven in the same way that bible doctrine is allegedly proven. To prove a bible argument one refers to the text itself, proving only consistency within it’s own text, totally independent of any real world.

    To prove a scientific theory, like evolution or global climate change due to fossil fuel combustion, one collects evidence from the real world and makes a case based upon probability.

    That case is not a vote amongst experts, every last expert could be wrong, as history has often proven. The search for what is true does not involve an appeal to experts or a voting process on what the consensus of experts think. (The zen of truth seeking is dialectic..aum)

    It is for every observer to consider the evidence and the argument to see if the case has been made. Then we can debate the merits of the case to decide on a course of action. The tactic of the anti-green faction is to demand a biblical standard of proof..or keep studying the problem without acting.

    But to demand absolute proof before adjusting one’s view of reality, is a dangerous approach, notably favored by the portion of humanity dedicated to obtaining their proofs from tautological religious and political philosophies. They are the true believers.

  29. Hans Erren:

    I would like to emphasise the difference between contrarians who have arguments like “co2 is not a greenhouse gas”, and sceptics who say that “the surface record has substantial errors”
    I know it is difficult to draw the line between contrarians and sceptics. But likewise it is difficult to draw the line between sceptics and “warmers”. Where would you place me?

    BTW I have seen some good work by you against climate alarmism on this site.

  30. Mark Frank:

    As you know from elsewhere, Hans, I believe you to be a paradigm of constructive scepticism, willing to take on the sillier arguments of contrarians as well as question the detail of climate science. :-)

  31. Jeff Alexander:

    Re #26 – The label I prefer is “denier” as in Holocaust denial. It indicates someone who deliberately misinterprets or ignores the evidence.

  32. CapitalistImperialistPig:

    William of the many names: “They need a label – what would you propose? – William]”

    I lean toward “minions of Exxons evil empire,” but that doesn’t roll quite trippingly off the tongue. Maybe “Minions of Exxon’s Oligarchy of the World” or MEOW? ;) There’s got to be a Syriana catspaw joke in here somewhere.

  33. Michael Tobis:

    Re #13, I agree in substance with some of the numbered points and not others. But I am struck by this:

    7) The glaciers are disappearing, so what? It takes 3000 years to melt Greenland

    I find this attitude deeply disconcerting. Whether it is 3 KA or more or less is not the issue. The question raised here is whether we are behaving responsibly in committing future generations to such enormous changes.

    Economists have an argument that things further into the future should be discounted, and while this may be useful in managing private investments it is not obviously sound as a strategy for public policy. Why should our interests in wealth and comfort outweigh those of our descendants for a stable environment?

    Economic theories are abstractions from social constructs, unlike physical facts. I am confident that if the ice caps begin to collapse in earnest, economic theory will shift around to assert that we should not have put our descendants at risk in the way we are now doing.

    One reason anthropogenic global change is interesting and challenging as a policy question is because it raises the issue of our responsibility to future generations. Most of the predictive efforts of climate science are being directed out to about a century, but the effects of our current behavior are likely to be felt for several centuries and perhaps millenia thereafter.

    This is why I find the “so what” in Hans’s posting so peculiar. It appears to be based on moral presumptions that at least ought to be made explicit and examined.

  34. Hans Erren:

    Michael, the the quote “the glaciers are disappearing, so what” is a translation of the title of an interview by Vrij Nederland with IPCC lead author Hans Oerlemans.

    “De discussie over klimaatverandering begint hysterische trekjes te vertonen,” zegt Hans Oerlemans
    (‘The discussion about climate change is starting to show hysterical symptoms’ says Hans Oerlemans)

    Is a melting glacier bad? Look at Toronto and Amsterdam, both located on places where there used to be glaciers.

    [Response: In and of itself, a glacier melting is not ‘bad’. Significant numbers of them melting are a clear sign of a warming world, and projections of the ice sheets melting have big implications for sea level rise. I would argue therefore that the implication of melting glaciers is more likely to be bad than good. – gavin]

    [Response: A little postscript: Glaciers reappearing where Amsterdam is now, or Greenland melting and Amsterdam disappearing under the sea, would actually be equally bad. We’ve had both situations in the past – “Amsterdam” under ice about 20,000 years ago at the last glacial maximum, and “Amsterdam” under water in the Pliocene, 3 million years ago, when CO2 and sea level were higher than today. None of these past climate states were ‘bad’. But the difference is: we now have Amsterdam and many other coastal cities in the world, and losing these through our own fault would be stupid. -Stefan]

  35. Jenkins:

    As long as scientists are trying to understand the mechanisms of climate change they are functioning as disinterested assayers of knowledge. But any kind of evaluative judgment about human intervention in natural processes is unscientific and is only ideological opinion. What does Global Warming mean? It means that there will probably be more thunderstorms of somewhat greater severity, probably more hurricanes of somewhat greater severity, alright coastal cities will have to move further inland and use stronger building materials in their architecture, more dykes will have to be built. It means that it might be warm in December and cold in July, that’s nothing to worry about too much. What else? Some flora and fauna will become extinct or they will adapt to the changing environment, Deep Ecologists will not like this but sane individuals will not be very concerned about it nor should they. It was ordained by the Judeo Christian God that Humans should have Dominion over the Earth. Science and technology are methods for expanding the Dominion of Human Empire, and all matter in the universe is only there for the exploitation by humans for their own selfish benefit, eventually all matter and energy in the universe will be harnessed to serve the interests of human beings. And humans are the only important life on the planet Earth possessing High Intelligence and self consciousness as the Brutes do not. From that objective outlook Global Warming is not something to be dismayed about but proof of humanities power and greatness.

    [Response: And now back to our regularly scheduled progams…. – gavin]

  36. Pat Neuman:

    In “Our elves, our selves”, Kay Harvey, St. Paul Pioneer Press, said:

    “Just when things are looking bleak, elves come to the rescue.

    “When the old shoemaker became too poor to buy more leather, elves sneaked in at night to stitch such fine shoes buyers lined up at his door. And when Santa could no longer grant all children’s Christmas wishes, elves took over and ran his workshop all year long”.

    Donna Casella, a professor of film, fantasy and pop culture at Minnesota State University (Mankato) said: “The real world is messy, Crime often pays, and some people die for no reason. In the alternative reality of elves, things can be fixed.” …

    “Our collective consciousness yearns for things more basic, things close to nature and the idea that whatever dies come back again,” Casella says. “It’s very comforting.”

    Lise Lunge-Larsen, a student of folklore who lives in Duluth and has written children’s books exploring the fairy kingdom, said:
    “People are attracted to mystery, the things that are not always explicable,” …

    “There has always been this sense the universe was inhabited by forces you could not see but you knew were there.”

    Above taken from: “Our elves, our selves”, by Kay Harvey (Dec. 16, 2005).

    If it’s true that “People are attracted to mystery,” then why aren’t more people interested in the mystery of climate change on Earth?

    I think most people know that global warming is serious, happening and primarily man-made. Thus there isn’t much of a mystery about it anymore. Furthermore, “In the alternative reality of elves, things can be fixed”, but in the reality of global warming, people know things won’t be fixed. Thus they don’t want to think about it, not interested.

    At first it was unclear to me what Hans meant (in 29) by saying “I have seen some good work by you against climate alarmism on this site”. After reading “Our elves, our selves”, it seems clearer to me now.

  37. Lynn Vincentnathan:

    RE #25, that CO2 is not a pollutant. Tell that to the disintegrating fish in the acidifying (from CO2) ocean. I don’t know if it actually causes fish to disintegrate, but up until last year when the ocean acidification evidence came out, I would have agreed that CO2, which plants need, was not a pollutant in the same way SO2 & N0x (+ sulfuric & nitric acids) and other pollutants are. Now I think, not only does excess CO2 warm the earth, creating (net) havoc, but also does other harms not directly related to GW. Yep, in my mind it is a regular pollutant (in excess).

  38. Vaughan:

    Okay, finally something this ecologist can comment on semi-intelligently. Environmentally speaking, the definition of a pollutant is “a resource out of place”. CO2 is lethal if it is in too high a concentration in your bloodstream. In the right concentration in the air, it is food for plants. Nitrogen is necessary for plant growth–but too much in a body of water casues eutrophication.

    Transfer of millions of tons of Carbon from the lithosphere to the atmosphere in a few generations–yeah, I’d call that pollution.

  39. Hans Erren:

    re 34:

    projections of the ice sheets melting have big implications for sea level rise.

    Which is exactly the fine line of alarmism. What’s the likelihood of the compound ifs?

  40. Terry:

    Having observed these discussions for quite a while now, I offer my two cents as to two important factors in the debate.

    1) A little snark can easily render the discussion unhelpful. There is an anti-Rasmus thread over at Climate Audit that is abnormally snarky and which I find quite off-putting. It is hard to resist the snark tempation, but in the end, posts are much more persuasive without the snark. Snark just makes it seem like you are cheering your team over theirs — that gets old real fast.

    2) Ignoring legitimate counter opinions is very destructive to credibility. When a reader finally hears the other side of the debate (usually somewhere else), he feels betrayed and much less inclined to believe future assertions. A good example of this was the recent post(s) here on the relation between hurricanes and AGW which elided Landsea and the earlier hurricane activity data.

    [Response: Agreed. There appears to be something inherent in the blogsphere that encourages that kind of thing, and we should be more vigilant at controlling it. Apologies. With respect to the Landsea criticism of the Emanuel paper, that has just come out as a Nature brief communications and we will likely post something on that soon. -gavin]

  41. Michael Jankowski:

    ***Yep, in my mind it is a regular pollutant (in excess).***
    If you want to define a “regular pollutant” as such, you can make a case for practically every physical to be a pollutant (Paracelsus: “The dose makes the poison”).

    A fun site to visit along the same lines

  42. Eli Rabett:

    If one wished to discuss the moral implications of climate change you would have to start by deciding the responsibility of the present to the future, and the gratitude that the present owes to the past. To frame this in religious terms you have to decide whether G_d gave dominion over the earth to mankind as a caretaker in G_d’s stead or to do with as wished.

    As you may guess, I detest heedlessness that lives only in the present for itself. Worse, I find it dangerous.

  43. Steve Bloom:

    Re #40 (T): RP Jr. has kindly posted the entire Nature exchange at . Don’t anyone tell Nature about this, as they’d probably have his guts for garters. :) I await with eagerness the new RC post on all of this.

    BTW, am I misremembering or has Emanuel said here for the first time that there’s now a clear connection between global warming and hurricane activity (albeit not yet detectable in the North Atlantic basin when taken on its own)? I don’t recall that he went quite that far before. Previously he seems to have used words like “probably” and “suggests”; now it’s: “I maintain that current levels of tropical storminess are unprecedented in the historical record and that a global-warming signal is now emerging in records of hurricane activity.”

  44. Michael Jankowski:

    ***Previously he seems to have used words like “probably” and “suggests”; now it’s: “I maintain that current levels of tropical storminess are unprecedented in the historical record and that a global-warming signal is now emerging in records of hurricane activity.”***
    Maybe that’s a difference between a paper and a communication response. In the former, you need to have evidence to support any claim you make. In the latter, you can speak with opinion.

  45. PHEaston:

    Bertrand Russell’s advice clearly applies to those who feel unqualified to make their own judgement. A genuine scientist, of whatever discipline, will be capable of assessing both sides of the argument and making his/her own judgement. The apparent aim of the ariticle to use Russell to argue that no-one should question the ‘consensus’ seems a little surprising for a scientific website. In any case, IPCC does not represent a simple consensus, as illustrated by the well-known resignation of Dr Landsea.

  46. Terry:

    Re: #40 and #43.

    I don’t understand.

    Landsea’s conclusions on the relationship between AGW and hurricanes have been well known for many years. Yet, they weren’t mentioned in the recent RC posts on the topic. Shouldn’t a website that seeks to reflect consensus science have at least mentioned Landsea? If only to acknowledge the existence of his conclusions so as to dismiss them?

    [Response: Re-reading the relevant post and the associated comments, I note that we linked to the NOAA NHC summary which claims that everything is a natural long term cycle, and that Landsea comment’s and paper’s made numerous appearances in the discussion. The topic is still very much under discussion. – gavin]

  47. Pat Neuman:

    re 46.

    The Response by gavin says: “I note that we linked to the NOAA NHC summary which claims that everything is a natural long term cycle”, …

    I’m not sure about that. Anyway, what might having NHC under DOC mean for NHC scientists doing R and D, predictions and post event summaries on hurricanes? Taking a view that frequency and strength of hurricanes are influenced by GHG emissions and global warming may not seem to be in the best short term interest or mission of the DOC. What kind of changes might there be in all this if NHC and National Weather Service were in a different department, like the Department of Defense?

    Link to nhc:

  48. Tony Noerpel:

    There seems to be two discussions regards AGW and its related problem, peak oil. The discussion that interests readers and contributors to is among very knowledgeable people with very specialized knowledge. But the far more important discussion takes place in the mass media among all people. While, hopefully, the former frames the latter, it is the latter which determines actual policy. Evolution has won the former debate but is fighting tooth and nails in the latter. Senator Inhofe’s star expert witness at his recent global warming hearings, Michael Crichton, was not even a scientist. Most Americans, whom I talk to, sincerely believe that AGW is a controversial theory with voluminous science on both sides. I’ve used Oreskes paper to show that this is not the case, thus my query regards how valid an assumption that is. Realistically, most people are not going to attend AGU meetings, nor would they understand the scientific jargon and acronyms enough to appreciate the scientific opinion. Unlike other problems, such as Y2K, in order to tackle peak oil requires immediate alternative solutions. In absence of AGW and other environmental degradation, one might assume that nuclear and the oxymoronic “clean coal”, are solutions. Unfortunately, if the majority can agree that AGW and peak oil are acute problems which need to be addressed, then conservation and “life style” sacrifice are going to have to be the largest contributors to the solution space. I believe that Japan (4200 kgoe/p/y) and Europe (3600 kgoe/p/y) demonstrate that Americans (8000 kgoe/p/y) can cut energy consumption in half without sacrificing Quality of life (life expectancy and infant mortality, for example). By the same measures, Cuba, which has a lower infant mortality rate than the USA, demonstrates that energy consumption can be cut even further. However, life style cannot be maintained. In order to convince Americans that living in a desert, farming chemically, driving Hummers and heating 5,000 sq. ft. homes with cathedral ceilings is unsustainable, it needs to be “prove” that AGW and Peak oil really are real in the larger debate. Unfortunately, I think somebody has to be an alarmist and everybody else has to panic. :+)

  49. Pat Neuman:

    re 48. Tony wrote: “Most Americans, whom I talk to, sincerely believe that AGW is a controversial theory” …

    Tony, where do you think “Most Americans” you talk to get their information about global warming? For many years, managers and forecasters at NWS offices and State Climatologists have been telling people that global warming is too controversial and too far outside of the mission of responsiblility for them to comment. Some have been more direct, actually downplaying any global warming significance. It seems that most people end up getting their information from non official sources, but some have been also getting their information from official sources expressing a “skeptical” view, like that given by Senator Inhofe and his “star expert witness” Michael Crichton.

  50. Hank Roberts:

    Thanks for comment #40 and Gavin’s followup. Blogging may feel like a conversation among intimates in which snarkiness — based on a lot of shared background ideas — is easy to slip into.

    But blogging is a public conversation — and those with no way to decide who has the facts right form opinions based on demeanor.

    Back in the 1960s, I attended a college debate between two scientists — one working for the chemical industry, an old seasoned public speaker, very professional; the other a young academic with expertise in bird reproduction. The question was whether DDT could possibly hurt birds. The chemical industry pro “won” in terms of the naive audience’s response to his well crafted barbs and arch ploys, as he goaded the biologist into being snarky and angry, then deplored his behavior, tsk tsk…

    Those of us who’d actually read the published research knew the chemical industry speaker was selectively lying — but few in the audience had a clue — and before the web, there were no footnotes and links in public discussions.

    Now, that kind of PR distortion can be caught out — trolls don’t footnote; PR types eventually get caught if they do, or exposed if they don’t and their opponents are careful to footnote references.

    My wish — for the mentioned climateaudit writers who comment there after reading here, as well as for those writing here — footnote even the snarky, witty, insider jabs — remember those of us who aren’t insiders on the science do pay attention to how it’s presented, and value the effort made here in public to talk about it as it’s being researched.

    Hard argument is good.

    “For a successful technology, nature must take precedence over
    public relations, for nature cannot be fooled.” – Richard Feynman

  51. Pat Neuman:

    re 40. My wish is for writers here to be specific, not imply things or make insinuations which may cause others to make false assumptions about what they meant in their writings.

  52. Francis MASSEN:

    Re #11, #16 and “alarmism” in general:

    Please read these 3 comments:
    1. Richard Lindzen:
    2. Hans von Storch and Nico Stehr:
    3. Margaret Wente:

  53. Francis MASSEN:

    Re #48:
    As an European, I am happy to be on the low end of the energy consumption scale. Lifestyle apart, you cannot move through the wide open US spaces with the same amount of energy that brings you from Amsterdam to Barcelona.
    It is quite easier to gobble less energy if distances and environment allow this. I fully agree, that the most important global problem is future energy availability, and if solutions to ***abundant and cheap*** non fossil sources will be on their way, the AGW discussion will become quiescent. I do not think that alarmism (and its derived Kioto-style bureaucratic monsters) is a great help in finding these solutions, but that engineering and technology are.

  54. Michael Tobis:

    Re #52:

    The statements attributed to Lindzen postulate a core argument of the denial camp; that consciously or unconsciously funding pressures motivate scientists to overstate risks. This argument is often made but rarely supported. While there is no reason to suspect climate science as a community to be immune from unconscious bias or conscious dishonesty, it is far from clear that this pressure causes the scientific community to overstate risks which the political sector (indeed, which anyone with good intentions) certainly wishes were nonexistent.

    The exactly contrary bias is equally plausible. The funding agencies themselves and the political sector that supports them are consituted by fallible human beings every bit as much as are the scientists they support. In the event that they are investigating a realistic risk, scientists who deliver reassuring news and refrain from raising alarms may be rewarded in preference to others.

    As far as I know, no one has come up with a reasonable way of testing which of these pressures dominate and to what extent they overcome the genuine pursuit of truth that drives people into the sciences in the first place.

    Von Storch’s essay is rather more interesting. I think he is explicit in discussing the European political context. That in the English-speaking countries is dramatically different. Nevertheless, some of the points he makes are very much worth considering.

    One can be alarmed without attributing every unusual wather event to climate change; indeed there’s a certain logical fallacy in doing so in that climate is the statistics of weather events. A change in statistical properties of a set of events does not cause a member event! “Global warming” didn’t cause Katrina even if it turns out that anthropogenic forcing of climate makes severe tropical storms more likely.

    However, I disagree with von Storch about whether it is excessive to focus on the IPCC worst-case emissions scenario. This scenario is the one with the most cost of those usually considered, so avoiding it is quite reasably the focus of conversations between science and policy. Furthermore, as there are other sources of carbon in the geochemical system, and as its perturbed response to the global change contempolated is not well-understood, even more severe carbon scenarios are plausible; these, having even larger cost, should weigh considerably in rational risk/benefit considerations even if they are considered unlikely.

    Also von Storch follows in the common pattern of cutting off consideration of the consequences of anthropogenic climate forcing at the arbitrary year 2100. In most of the usually contemplated scenarions, the perturbation shows no sign of deceleration by that time. I find this to be dodging the question of our obligation to future generations rather than addressing it.

    Von Storch asks Climate change of man-made origin is an important subject. But is it truly the “most important problem on the planet,” as an American senator claims? Are world peace, or the conquest of poverty, not similarly daunting challenges?

    The answer to this is that of course peace and prosperity and freedom are the motivators of any political conversation. Clearly the achievement of these goals is dramatically easier in a stable physical environment than in an unstable one. The contrast of these questions against forced climate change is a false dichotomy. It is because we are concerned about poverty and war that we worry about climate change. If cliamte changes too fast the result will be poverty, exploitation and war.

    The question of anthropogenic climate change challenges many of the assumptions under which we operate. For the first time the world is committing its descendants to a significant deterioration in the stability of its physical environment on a time scale longer than normal political and economic processes can effectively operate, Communication of this fact and its implications to the public and to the policy sector has turned out to be dramatically more difficult than might have been anticipated. This situation is not independent of the geopolitical and global economic situation. We aren’t just talking about buying more umbrellas and fewer snow shovels, or saving a few interesting turtles. We do not exist separate from our environment, and no law of physics or chemistry prevents us from devastating it quote thoroughly as a global consequence of decisions taken locally in rational self-interest.

    Calling anthropogenic global change the most important issue of our time is not obviously in error.

  55. Hank Roberts:

    Dimethylsulfoniopropionate ((CH3)2S+CH2CH2COO�

    Anthropogenic effects won’t be understood unless we are different than any other form of life.

    We know what life on Earth does, given access to a previously limited resource.

    Boom and bust.

    What could we possible learn that would make us different?

    Lindtzen’s saying we don’t know cloud physics yet, but that we do know increased CO2 leads to more clouds —

    Lovelock predicted warming –> CO2 –> plankton -> clouds –> cooling — the mechanism was found fairly quickly. Plankton produce cloud nuclei, see Dimethylsulfoniopropionate.

    CO2 released in recent centuries equals or exceeds releases that happened as positive feedbacks after natural warming events.

    Whatever else is happening — human activity isn’t trivial, even though we don’t know for sure what human activity is contributing to the current situation.

    We had an amazingly close call and good luck that chlorine, rather than bromine, was the preferred basis for fluorocarbon chemistry in the research stage. Had a bromoflourocarbon rather than CFC-based industry developed, we’d have lost the ozone layer before the problem was understood and recovery would have taken far longer.

    Being prescient doesn’t mean being right — Lovelock said he didn’t imagine that CFCs could pose any hazard; today he says nuclear power is the only hope — but any scientist outside his or her known specialty is just another hopeful commentator.

    We need the research, if we have time to get it done and understoood before what we’re doing catches up to us in feedbacks.

  56. Coby:

    From the link in #52 Lindzen says:
    “Scientists make meaningless or ambiguous statements.
    Advocates and media translate statements into alarmist declarations.
    Politicians respond to alarm by feeding scientists more money.”

    Like Michael Tobis, I hear this very often but see little or no support for it. In fact, I am aware of anecdotal evidence that contradicts this. Think about the EPA and drug testing, do the scientist who find alarming side effects get the funding and accolades? What about the alarming discoveries about lung cancer a tobacco? It sure took a long time for that bit of common sense to penetrate public policy. Back to climate research, didn’t I read recently about cuts to NOAA or NASA for global data collection projects for CO2 emissions? Were the emissions findings not sufficiently dramatic leading the Bush administration to cut the purse strings?

    I followed a link on that page to an interview with Lindzen and he brought up the fallacious argument about the “precautionary principle” dictating that until we are very sure that CO2 effects climate we should not take action to curtail CO2 production. All I can say is this has been a very effective bit of spin and I hear it all the time. But the fact is, the people espousing this position have it 180o backwards! What we are doing right now is action that is altering the atmosphere. The precautionary principle says we should not take this action until we are sure it is safe. The onus is on pollution advocates to demonstrate that there is no danger. This bit of spin has succeded in making “full speed ahead” equivalent to wait and see.

  57. Coby:

    Just a further comment on Lindzen and the precautionary principle, which he states in an interview here:
    “The notion that if you’re ignorant of something and somebody comes up with a wrong answer, and you have to accept that because you don’t have another wrong answer to offer is like faith healing, it’s like quackery in medicine – if somebody says you should take jelly beans for cancer and you say that’s stupid, and he says, well can you suggest something else and you say, no, does that mean you have to go with jelly beans? ”

    To readjust his analogy to fit with reality: it is like you are in the habit of eating large quantities of jelly beans since a few years ago and now have cancer that began a few years ago. There is strong evidence that jelly beans cause cancer. It is not like “quackery in medicine” for your doctor to recommend cutting back on the jelly beans, it is common sense precaution. Especially when there are no other good explanations for your illness.

    And I will mention it again, we are running low on jelly bean production versus demand, there is a limited number of jelly beans available on the planet and there are many other good uses besides rotting our teeth. This means that even if it turns out jelly beans don’t cause cancer, our precautionary actions will have led to other benefits.

  58. Jo Calder:

    #57: it is common sense precaution. Especially when there are no other good explanations for your illness. Doesn’t this analogy confuse precaution with moderation? Cheers, — Jo

  59. Chris Vernon:

    Regarding Naomi Oreskes paper in Science has anyone come across this guy: Dr Benny Peiser, Liverpool John Moores University, UK

    I have been sceptical of anyone claiming a scientific consensus on the back of the Oreskes paper ever since reading the above link. The scientific consensus is often quoted (including by myself in something I wrote in the past) but no I’m no longer so confident.

    What’s the truth behind the Oreskes and Peiser debate?

    [Response: See Tim Lambert’s pieces (here and here) where he examines all of the claims and counterclaims and finds that Peiser’s argument is completely without merit. Note that Oreskes point is not that no skeptical papers were published, but that if there wasn’t a broad consensus, she would have found more of them in her search. – gavin]

  60. Hank Roberts:

    I read that series of exchanges, starting with Peiser’s CCNet attempt to slap down the research and Lambert’s and others’ critiques, as it happened and end up agreeing with Lambert — the results of such a search depend on understanding how to craft a Boolean search. That’s doable but not always easy, using Google — Peiser didn’t have that clear to start with, so there was some back and forth to get to where everyone was looking at the same thing.

    As with much else, it because a huge fuss over methodology, effort that could better have been put simply to re-asking the question in a way that all concerned agreed was better crafted to extract information. Like the ‘hockey stick’ thing, it sort of descended into ankle-biting perfectionism. If that’s not a horribly mixed metaphor.

    Peiser’s endlessly entertaining. His CCNet focused for a long while on earth-crossing objects and possible impact evidence going way back in time — looking for evidence on the ground to match stories from history and legend. I’d love to see a serious attempt to match up the ice core dust events with his collection. I do suspect he’s got a good point in that an old comet’s prior orbital tracks may be a braided area of tracks each full of small debris all along its length. Earth running through one of those, even without intercepting any single chunk big enough to make a flash-bang-hole-scar, could still sweep up a huge amount of dust and water and methane and whatever else a comet’s made of. Those could cause climate impacts.

    My hunch as just an interested reader is that he might take the climate scientists more seriously if they’d take his collection of suggestions for possible extraterrestrial-influenced dust events more seriously and look for them in the ice cores. (I presume that the ice core research isn’t throwing anything away and if there’s evidence there for forcings from extraterrestrial impact events im it will turn up eventually, but I don’t know if that’s so, or even what they’d look for.)

  61. Chris Vernon:

    Thanks Gavin, that Oreskes/Peiser discussion has gone a long way to restoring my confidence in the idea that the scientific consensus is with anthropogenic climate change. If only a similar consensus could be reached regarding peak oil – I spoke with Sir John Haughton a few months ago about IPCC assumptions regarding peak oil in the models and was disappointed to hear him pretty much dismissing the idea. I didn’t get the impression he really knew anything about peak oil, repeating the common arguments of higher prices making more reserves available and “vast amounts of oil in Canada” etc… I don’t believe an imminent peak in oil extraction is on his radar.

  62. Steve Bloom:

    Re #60 (HR): I could be wrong, but my suspicion is that a way easier method to look for comet dust would be by direct astronomical methods. I also suspect that astronomers have already looked and found nothing of note. That said, I do know that the ice cores contain obvious signatures from volcano dust, and one would think that any dust anomalies not explained by volcanos or other natural sources (post-glaciation loess, e.g.) would have turned up already. IMHO, Peiser is simply a contrarian who cannot be made happy by anything short of a whoesale overturning of the consensus.

  63. Steve Latham:

    Re: Comment #52.
    Others have responded to the first two links; I thought I would mention Margaret Wente of the Globe&Mail (Canada’s primary national paper). She wrote during the bombing of Baghdad in 2003 that contrary to all of the alarmist prognostications, regular Iraqis were not being harmed. I think that says something about her (and her objectivity), but I don’t want this to be just an ad hominem attack — here’s what the link provides:

    “We in newsland regard ourselves as hard-headed, skeptical objective folks. But show us a forlorn polar bear on a melting ice floe, and we check our brains at the door. Our environmental coverage regularly serves up the most hysterical, most credulous and most selective stories in all the news. The truth is, most of what passes as environmental reporting is little more than cheerleading for the Sierra Club and the World Wildlife Fund. It’s about as objective as the news reports you used to read in Pravda quoting party leaders on the glorious 14th party congress.
    The difference is, in Pravda, all the news was always good; on the environmental beat, all the news is always bad.”

    1. The first point to make is that the majority of news, in a losing battle, is likely to be bad. If you want to adhere to (or hold as an ideal) the SCUBA diver’s ethic of “Take only pictures, leave only bubbles,” then your chances of success aren’t great. Environmental reporting isn’t special in this regard — how much of the newspaper is about somebody getting frightened, hurt, or killed somewhere versus the frequency of those things not happening?

    2. An interesting problem is that “nature” can’t be “saved” in-perpetuity. This is asymmetrical with how attributes of nature can be destroyed. So when some ancient forest is about to be clear-cut or when some species is projected to become extinct in the near future, one can imagine the difficulty in finding editors who would think it worth printing a story describing how 5% of the forest will be preserved (with an option to log 10 years from now), or how some species won’t be wiped out by hunting within 10 generations but by land conversion within 15. With climate change the dominant perspective is that the effects are pretty much irreversible, too. I very much doubt that the press wouldn’t cover development of good way to sequester carbon….

    3. What’s the positive side that objective reporting would present when the news item is that polar bears seem to be starving/drowning due to melting sea ice?

    4. How many stories have been written on that woodpecker in Arkansas that didn’t go extinct (yet)? It’s a lie that only bad news is printed.

    I can’t really link this back to How to be a real sceptic. Maybe someone else can.

  64. Eli Rabett:

    It is interesting to look at the list of state climatologists in the US I’ll pick out a few who might be known to the readers of this list: Alabama Dr. John Christy, Colorado Dr. Roger A. Pielke, Sr., Virginia, Dr. Patrick J. Michaels

  65. Jim Glendenning:

    Lynn in #12 said, “Suppose the mainstream climate scientists are wrong & the contrarians right, and we act as if the scientists are right, then we have nothing to lose & something to gain in terms of reducing other environmental harms (acid rain, local pollution), resource depletion, and increasing national security (re oil wars & protection), and lots of money to save from energy/resource efficiency & conservation, and increasing from alternative energy.”

    I think he makes a good point. Working to reduce fossil fuel use, if done inteligently and without harming the economy could kill several birds with one stone: Make a finite resource last longer, provide better national security, protect the environment, and slow or stop AGW.

    In #48 Tony said, “There seems to be two discussions regards AGW and its related problem, peak oil. The discussion that interests readers and contributors to is among very knowledgeable people with very specialized knowledge. But the far more important discussion takes place in the mass media among all people. While, hopefully, the former frames the latter, it is the latter which determines actual policy.”

    Tony touches on the fact that the debate is about energy supplies and usage as much as it is about the science behind AGW. When environmentalist organizations quote AGW theories and say the world as we know it is coming to an end unless we do what they say, Joe Sixpac is not impressed. However, when the price of gas at the pump reaches $3/gal. it gets Joe’s attention. In fact gasoline prices are already affecting auto buyers choices. The hybrids are flying off the lots.

    When Joe Sixpac is told global temps may increase by 1 degree in the next hundred years, he has no idea why he should be worried. However, when someone convinces him that world oil production will soon reach its peak and begin declining with ever increasing prices for energy, that is something he can understand.

    Large reductions in the use of fossil fuels are only possible through command and control of the government. In a democracy the governed must consent to such changes. So it seems to me that if cuts in fossil fuel burning are going to be achieved, they wiil be achieved because the population is convinced that it will save them money and increase national security, not because it will affect AGW.

    If the world is going to continue to modernize and peak oil is near, then new clean sources of energy must be brought on line. Conservation through more efficient cars, light bulbs, appliances, etc can help. Solar, wind, and biomass can also help. But, until hydrogen or fuel cells are perfected we must turn to nuclear and hydro-electric to bridge the gap.

    As to the AGW skeptics. It seems to me there is a fairly strong case for CO2 and AGW. However, those of us who have looked at paleo-climates and the fact that it has been much warmer and colder here on Earth in the past when there were minimal human effects, makes us think there may be other factors at work. The scientists here at RC occasionally give a nod to other factors, but are absolutely convinced that those other factors are only background noise. That makes skeptics question whether you have open minds.

    Another problem is that the computer models of climate change that have been put forward may be perfect. However, they can’t be verified until fifty years or more have passed. Many people are opposed to taking draconian steps in energy usage without better proof. So they demand more information and continually find fault with the computer models.

    I, for one, think that this debate should be widened to include people from the natural resource industries, energy experts, the auto industry, government, and citizens all joining in because it really is about the future of this country and the world. I applaud you for having this discussion.

  66. Thomas Lee Elifritz:

    #65 – What debate might that be? There is precious little to debate anymore, except perhaps – “When are you going to change your lifestyle?”

  67. Steve Bloom:

    Re #64 (ER): While we’re talking state climatologists, three others who are public contrarians (i.e., beyond just being skeptics IMO), are David Legates (Delaware), James O’Brien (Florida) and George Taylor (Oregon). A belated thanks to LA (#25) for pointing out that John Christy is indeed a public skeptic (albeit not a contrarian as such and not very active of late).

    While I’m on the subject, the two folks Eli mentioned are not skeptics as such, although Pat Michaels is very happy to take money from the fossil fuel industry to promote the idea that any warming beyond the minimum IPCC scenario is balderdash. The other, Roger Pielke, Sr., is a little hard to encapsulate, but he does accept the consensus with the caveat that he thinks a larger proportion of the warming is due to anthropogenic changes than do most climate scientists, plus he wants the world to beat a path to his door in terms of how climate change is measured and described.

  68. Pat Neuman:

    re 64

    Another fairly well known State Climatologist is George H. Taylor, for Oregon.

    The State Climatologist website for Minnesota is at:

    The “Policy Statement on Climate Variability and Change” by the American Association of State Climatologists AASC) is at:

    The policy statement referenced by the state climatology offices was approved by AASC in Nov 2001.

  69. Pat Neuman:

    re 64.

    The public continues to hear that climate change is a “highly complicated and politicized field of study” from AASC government professionals. That must change. What does the public need to hear instead?

    For comparison:

    “Careful measurements have confirmed that CO2 is increasing in the
    atmosphere and that human activities are the primary cause. CO2
    measurements have been taken directly from the atmosphere over the
    past few decades. CO2 trends for earlier times have been derived
    from measurements of CO2 trapped in air bubbles in glacial or polar
    ice. The 36% increase (in 2006) in atmospheric CO2 observed since
    pre-industrial times cannot be explained by natural causes. CO2
    concentrations have varied naturally throughout Earth’s history.
    However, CO2 concentrations are now higher than any seen in at least
    the past 650,000 years”.

    Note: As of October 1, 2005, the Climate Monitoring and Diagnostics
    Laboratory has merged into the Earth System Research Laboratory
    (ESRL) as part of its Global Monitoring Division (GMD). GMD’s mission is to observe and understand, through accurate, long-term records of atmospheric gases, aerosol particles, and solar radiation, the Earth’s atmospheric system controlling climate forcing, ozone depletion and baseline air quality, in order to develop products that will advance global and regional environmental information and services.

  70. Tony Noerpel:

    Echoing Chris #61, thanks Gavin et al. for the discussion on Oreskes results. It is interesting to point out that Judge John Jones’ recent ruling in favor of evolution over ID contains this statement. “A final indicator of how ID has failed to demonstrate scientific warrant is the complete absence of peer-reviewed publications supporting the theory. Expert testimony revealed that the peer review process is exquisitely important in the scientific process…” [as reported in the Washington Post, Sunday, Dec. 25]. I believe that there was a paper by Scott and Cole, 1985 which examined peer reviewed papers on evolution and creationism using similar methodology as Oreskes. Of course if we have to wait 20 more years for this argument to be successful as applied to AGW…

  71. PHEaston:

    Re Pat Neuman (69); Here you make the misleading, but unfortunately common mistake of ‘answering the wrong question’. There are very few, if any ‘skeptics’ who question whether humans have caused a significant increase in CO2 concentrations in the atmosphere. The relevant issue is whether this is causing, or is likely to cause, significant changes to the climate.

  72. PHEaston:

    To Chris Vernon (61): I suggest you look a little more closely at the Oreskes/Peiser debate referenced by Gavin. The first reference consists mostly of people “having a good laugh” at Peiser, despite the fact that he published all of the relevant abstracts and makes an amicable defence of his point of view within the online debate. Most of those criticising Peiser seem to – either naively or deliberately – misunderstand his point by getting into semantic arguments about which specific papers are “for” or “against”. It is very quickly clear from browsing the abstracts that, like much of the evidence in this debate, it can be interpreted very differently depending on your own personal bias. The main point that Peiser makes is that Oreskes arguments contained sufficient limitations and a lack of clear methodology, that it does not accurately demonstrate a proof of consensus.

    The second reference focuses on agreeing that Oreske’s work should be as closely scrutinised as Peiser’s. But, unfortunately, the contributors over-readily accept her response to a request for background information on her research, that she is “too busy”. Why be so keen to prove Peiser wrong, but relatively indifferent about proving Oreske right? I cannot help concluding that this may be because she came up with the ‘right answer’.

  73. Pat Neuman:

    re PHEaston (72); I wasn’t asked a question that I can see.

    Anyway, so what fraction of the 36% increase in CO2 do you think might be a result of “natural causes”?

  74. Lynn Vincentnathan:

    RE #72, as mentioned, at this beginning stage in our AGW experiment, we do have to rely more on physics and good theories to answer questions. The final results of the experiment (which might turn out to be much warming and 50% or more of life destroyed??) may not be in for hundreds or thousands of years.

    I think it is well accepted that GHGs, such as CO2, have helped to warm the earth — is it 32 degrees C (??) — beyond what it would be without GHGs, allowing life as we know it to exist — the natural greenhouse effect. So, in order to make a counterclaim that A-GHGs do not further warm the earth beyond this natural level, we would have to have some really good theory or knowledge that atmospheric CO2 beyond, say, 400 ppb (or is it ppm) greatly loses its ability to warm the earth — e.g., the effect decreases arithmetically, geometrically, or exponentially, or by some other function.

    Is there any such theory or knowledge that would indicate this?

    Even if there were, we’d still have to consider that some effect (sensitivity) remains, and that the warming might lead to further (natural) releases of CO2 & CH4, as evidence increasingly is showing us.

  75. Barton Paul Levenson:

    Re #28 and “But of course no scientific theory can be proven in the same way that bible doctrine is allegedly proven. To prove a bible argument one refers to the text itself, proving only consistency within it’s own text, totally independent of any real world.” I thought comments on religion were going to be removed, gavin? I mean, that’s what you said about my post #17 above. You are applying the standard consistently, aren’t you?

    [Response: I’m trying to. Please (to all) no more digressions into theology! – gavin]

  76. Kenneth Blumenfeld:

    Re: # 49, 64, 67, 68 and other state climatologist-related remarks:

    I just want to clarify a few things, having spent some time at the Minnesota State Climatology Office (SCO).

    First of all, State Climatologists (SCs) are by no means a unified bunch; they have annual meetings, disagreements, polarized views and the like.

    Second, the responsibilities of each SC vary considerably. Some folks hold an office in a related academic department and occasionally field questions from the public; some conduct research; some do quite nearly nothing; for some it is a full-time job, for some it is part of a rotating appointment.

    In Minnesota, our SCO engages almost exclusively in improving and maintaining local climate data networks…something that we applied climatologists greatly appreciate. They do not conduct formal research, they do not publish, and they are thus not (expected to be) up-to-date on climate science literature. I am not sure they are actually qualified to speak on global warming, despite each holding degrees in meteorology.

    I don’t think our State Climatologist would want me characterizing his views, but I’ll say that he walks to work, hikes a lot, wears flannel, hunts mushrooms and does other rather crunchy things. What side of the debate would you put him on now? My point is only that the position of State Climatologist does not imply subscription to a particular set of views within the climate change debate.

    I otherwise think this thread is very useful.

  77. Michael Tobis:

    While I don’t always agree with Lynn V’s points, I’d like to commend posting #74 as capturing the situation both concisely and precisely. While I usually agree with Coby, I think Lynn’s is a much better answer to the jellybean challenge than his #57.

    The skeptics’ label is really going the wrong way. We know that greenhouse gases have a major effect on climate, and we know that humans are causing a major effect on greenhouse gas concentrations. I am skeptical that an argument may be constructed wherein unrestrained emissions of CO2 constitutes a reasonable risk.

    Anthropogenic CO2 is a perturbation to the global environment with known effects on the radiative properties of the atmosphere. Several streams of evidence are roughly agreed on the magnitude of the perturbation. There appears to be a large response with several delays built in, one essentially immediate, another on the order of decades (adjustment of the upper ocean) and others much longer (adjustment of the deep ocean and the ice caps).

    I really doubt that (I am really skeptical that) pushing this system any harder than we absolutely must is a good idea. I don’t want to see shoulder-shrugging, suspicion-mongering, and tiresome sniping at serious investigators; that simply doesn’t matter. I want to see an absolutely bullet-proof theory that explains why the risk is small enough to justify business as usual.

    Such a theory is not being offered, and that ain’t jellybeans, folks.

  78. Pat Neuman:

    There is a critical need for the public to be educated about climate change. For professional climatologists to be working exclusively on improving and maintaining local climate data networks, and not helping the public become educated about climate change, is not serving in the best public interest.

    [Response: You should probably be aware that profession of climatology as classically defined is much closer to what the state climatologists are doing than it is to what the RealClimate scientists do. It’s not therefore their fault that the nature of the science (and the work that climate scientists do) has shifted underneath them so to speak. – gavin]

  79. Thomas Lee Elifritz:

    #77 – But clear solutions to the carbon problem are being offered. The science is very strict. Are you changing your lifestyle? Somehow, I doubt it. Those who are clamoring for change the loudest, are often the last to implement it.

  80. Pat Neuman:

    Saying the nature of the science shifted underneath them is not a sufficient excuse for having ignored climate change and global warming. As a hydrologist, it was clear to me nearly six years ago that climate change was already in progress within the Upper Midwest. I did my best to let people know about that, at personal and professional expense. How can anyone not be concerned enough about global warming to do what they can in trying to help?

  81. Eli Rabett:

    Let me point out that all I said was: “It is interesting to look at the list of state climatologists in the US. I’ll pick out a few who might be known to the readers of this list:” and I provided the list. Having stirred the pot a bit, I think others have tossed some tasty morsels into it, for which I thank them.

    It is most interesting to contrast the official statement of the State Climatologists with the AGU statement on anthropic climate changes. It is also important to note that State Climatologist is an official position and carries with it the appearance of speaking officially. This has been used by Pat Michaels, for example, as a certification of expertise. It is, in my opinion, wrong to claim that they have no interest in speaking on global climate issues, although particular members may not.

  82. Michael Tobis:

    Re #79; I agree that some solutions are evident or emerging, though not without cost of their own, most notably nuclear power. What concerns me is that they show few signs of being implemented.

    I can’t see any basis or justification for Thomas’ jumping to (in my opinion incorrect) conclusions about my own behavior. It’s irelevant and a red herring.

    (This problem can only be slightly ameliorated, not solved, at the retail level. Most emissions are from industrial sources. I have never so much as touched a piece of coal, so I can’t easily cut back on my share of the demand for the stuff.)

    To reiterate my point and avoid getting derailed, since we have at the very least a plausible argument for a severe risk, the burden of proof falls on the business-as-usual folks to refute it. They don’t have anything resembling a coherent theory.

    Most of the public conversation on this topic is totally upside-down. If I am storing oily rags next to your house, I don’t have the right to demand that you predict with certainty and precision when your house will be immolated before I consider, maybe, reducing the rate at which I add more rags to the pile!


  83. Thomas Lee Elifritz:

    Hey Michael – you are burning oil *IN* my house, as am I. I have a perfect right to complain about your burning, just as I have a choice to reduce my own burning. I have monocrystalline solar panels. I have solar hot water heaters. I have wind generators. I am collecting and storing insulation, rather than say, burning the raw materials for making insulation. The whole skepticism thing is moot. It’s over. Get used to it. So, tell us, not just Michael, all of you, when are you going to start changing your lifestyles dramtically. What are you going to do about the carbon problem. Remember, I know your carbon footprint. I can even see you clearly from orbit. You have no secrets anymore. I’m watching you.

  84. wayne davidson:

    #78, Pat, opinions, I hear them all the time, from the pros but not as much as from ordinary folks, they know about GW, they don’t need me to tell them that the climate is changing warmer, they run into trouble in finding some expert willing to explain it though, they come up with their own theories, best way they can, but rarely get educated on the correct science, there seems to be a loose structure, a quality in freedom of education, a media weakness easily exploited though ….. Who do you call about GW? Who do you rely on explaining it correctly? Your fellow Minnessotan State climatologist wont say anything, Lucky if you go to RC website and can understand what we are writing about, but it often never gets to that point because every thing is confused….

    As a lay person, there are huge reasons to be skeptical about what we are hearing, broadcasted daily, we have a bigger problem than a handful of contrarians getting 50% of the medias time, the entire met structiure is unable to present the situation well, even the best presenters go along their merry way leaving out temperature anomalies for someone else to report. It gets worse, especially when they try to explain it: like the latest lame sound bites from TV met specialists, especially for this yet to be very cold winter. Flash back to September: “Cold winter is coming” yes it was….. err not so far, just read about a new excuse: La-Nina, of course it isn’t raging to new SST coldness, but clever , especially totally disconcerting distraction isn’t it? Could it be that we understand seasonal forecasts in simpler terms? Like the theory of persistence ? For example:

    Very hot Global summer + fall = not so cold a coming winter (if there are no extraneous inputs, volcanoes etc…).

    Contrarians have a field day because we fail to redress basic media diatribe:

    one: Some Climate forecasts are very good, they seldom get correct attention from the medias. Well they must reach a bigger audience more often.

    two: Clear distinctions must be made when a seasonal forecast are transmitted, I seldom hear
    the reasoning for them in the first place, it appears from a GCM and no questions are asked. These same seasonal forecasts do have probability of success attached to them, if one reads carefully, and they are simply not repeated, no fault to the forecasting agency, but I doubt the intentions of those who simply fail to state those probabilities, year after year. It serves mostly the purpose of contrarians, how delighted they may be when another seasonal forecast flunks again.

    For this I am skeptical that we can clear the majority of minds, and make way to a better solution, unless a stronger voice/authority can make it through this morass, we have a lot of work ahead, and foremost we must eliminate contrarian fuel for their raging virtual fire.

  85. PHEaston:

    Re Pat Neuman (73). Probably almost none of the 36% increase in CO2 is from natural causes. What I meant by “answering the wrong question” was that you appear to present a certainty regarding the cause of CO2 increases as certain evidence for AGW – not in response to a specific question, but as an answer to the general GW debate. Remember that despite the apparently big numbers when you consider CO2 in isolation, Man’s emissions remain < 0.5% of the GW effect. Despite the conviction of many, there is not a consensus that this represents a signficant and terrible threat.

    It is a very big mistake by many contributors to this site to assume that anyone who challenges their view does not care about the environment or humanity. Acting on AGW theory is not without risk. There are financial costs; a potential hindrance to human development that has dramatically improved our quality of life, life-expectancy, etc; and a risk of diverting our attention away from dealing with issues that we know – without debate – are killing millions every year: lack of clean drinking water, malnutrition, malaria, Aids, etc. As a hydrogeologist (similar to Pat Neuman’s hydrology), I am very much in favour of protecting our natural environment. The most important thing, as scientists, is that we are able to maintain an honest and sensible debate, without it being clouded by poor science, poor logic and politics.

  86. Tony Noerpel:

    Question: I understand that John Christy measured atmospheric temperature using weather balloons. He compared his recent results with historic values. The problem was that historical values were not accurate to the precision required because they were not at the time intended for that purpose. Christy determined how to calibrate the older data. His initial results did not show the atmospheric warming that the AGW model predicts. In 2004, some researchers discovered a mistake in Christy’s calibration. They argued about it for a year and finally determined that Christy was wrong. Is this true and has it been addressed already on realclimate? Thanks.

  87. Kenneth Blumenfeld:

    Re: #78 (including Gavin’s response), #80
    “There is a critical need for the public to be educated about climate change.” Agreed, which is why we should urge the real experts (e.g., those on this site) to increase their visibility in the public sphere…so the public can have the information from the source(s), rather tha from lay distillations.

    “For professional climatologists to be working exclusively on improving and maintaining local climate data networks, and not helping the public become educated about climate change, is not serving in the best public interest.” I disagree. Without the data and the networks, many research climatologists or, “climate scientists,” would be out of a job. And keeping these networks going is a full-time job.

    I am all for the creation of state-level appointments that deal more explicitly with the ramifications of climatic change to state resources and commerce. I wish we had someone who did that right now (maybe some states do?). Something like a climate change outreach person within the SCO. The MN State Climatology Office currently does not have that capacity, but maybe once budgets fall on happier times it could be on the table.

    As far as “the nature of the science shifting beneath their feet,” I would just remind you that (at least for the MN State Climatologists) we are talking about the suppliers of the data versus the direct users (i.e., those who do research). In that sense, any shift in research foci would not be relevant to the data suppliers, unless somehow the data had become inadequate or inappropriate for the intended analyses.

    Re: #81:

    I agree with you. PM may wrongly use hit title as a certification of expertise, but that does not mean others should, especially if they have not formed their own opinions. For his part, I will say that Michaels does research on global climate issues (regardless of what we may say about that research), whereas most state climatologists do not.

  88. Pat Neuman:

    re: 85 PHEaston wrote: > Probably almost none of the 36% increase in CO2 is from natural causes.

    Some contrarians have claimed that small increases in solar radiation could have enhanced global climate warming by significantly larger amounts than by the amount of solar radiation alone, in claiming that the small increases in climate warming by solar radiation would trigger increases in natural emissions of CO2 from plants (more food from radiation and longer growing seasons). Your answer implies that you disagree with the contrarians on that claim.

  89. Pat Neuman:

    re 87.

    Framing of Climate Science (RC article, Nov 17, 2005) includes a discussion of the way in which climate science is “framed” …

    I think the Policy Statement on Climate Variability and Change by the American Association of State Climatologists* “framed” climate science to involve more uncertainty than the research, modeling and climate data studies warranted.

    In placing undue emphasis on uncertainty, AASC downplayed the efforts of hundreds of scientists by reducing or eliminating public expectations that global warming could become catastrophic.

    * The AASC Policy statement shows: …

    2. Climate prediction is complex with many uncertainties – The AASC recognizes climate prediction is an extremely difficult undertaking. For time scales of a decade or more, understanding the empirical accuracy of such predictions – called verification – is simply impossible, since we have to wait a decade or longer to assess the accuracy of the forecasts.

    * The AASC is the professional organization of State Climatologists of the United States. Each State Climatologist is appointed in his/her respective state to provide expertise on issues associated with climate. … (AASC, 2001)

  90. J. Sperry:

    Re #86 (John Christy’s measurements): It looks like these posts from Aug 11 and
    Nov 18 discuss the topic.

  91. Barton Paul Levenson:

    The problem with the Sun being the cause is that we pretty much know all the Sun’s cycles on a human time scale. Global warming doesn’t seem to be a cycle, it seems to be a one-period event. If the Sun is really causing a 1 Kelvin increase in our temperature per century, and it’s not cyclical but linear or even exponential, humanity is screwed and we’re all gonna die.

    Just thought I’d mention that.

  92. Lynn Vincentnathan:

    RE #54, and GW “didn’t cause Katrina” because GW is only about overall statistics & not individual events.

    I might be wrong, but I don’t think scientists are ruling out GW’s possible role in enhancing Katrina. While they cannot attribute Katrina to GW (or even to the increased average warming of the ocean from GW), neither can they say GW did not enhance Katrina’s intensity. Correct me if I’m wrong.

    Maybe a way to look at it is that there is (1) GW, the statistics scientists gather and analyze, and (2) GW, the reality (of which no one has complete grasp, leaving room for skeptics to doubt that GW is real & contrarians to cause a big fuss over). GW1 tells us that on average the world is warming. GW2 (reality) reveals an uneven pattern of warming — some places are getting cooler, but most places are getting warmer, some a lot warmer. The SST that helped spawn Katrina was 6+ degrees F above normal; it could be a fluke normal random fluctuation (due to a host of natural causes), or…maybe normal fluctuations, plus the shallowness of the Gulf of Mexico coupled with GW, causing some greater SST increase. However, the best we can do is statistics (coupled with theory), so scientists cannot (yet) attribute single events to GW.

    Another way to look at it is, culture is a way of constructing reality. I assure my students that I, for one, believe there is a real reality. Let’s call it R. However, we cannot perceive it directly, but only through our sociocultural constructions of it, r1, r2,….rn. Science is one of those ways of constructing reality; though it is powerful (& “skilled”), it is not the real reality. And it has developed in time hopefully to help us understand and avert the ill effects of AGW (the reality); I hope not simply to in excruciating detail those effects as we continue to render the earth less and less inhabitable for humans & other species. AGW skeptics and denialists have different constructions of AGW (as false, or not so bad), as do environmentalists, who may be skeptical of science, that it is unable to tell us (yet) the more gruesome story that is beginning to unfolding & may soon become irreversible for a long time.

    Personally, I think Katrina may have been enhanced by GW to some extent or the other, and my impression is that idea is no more right or wrong than that of any one else. Scientists just can’t prove it one way or the other.

  93. PHEaston:

    Re Pat Neuman (88)
    1. My full response (85) to your earlier comment is not displayed.
    2. What do you mean by ‘contrarians’? It sounds like a good description for those who are contrary to open scientific debate.
    3. I am not familiar with the arguments you refer to. Perhaps I should look into them.
    4. The principal issue is not: what causes CO2 increases; it is: what is the impact of CO2 increases.

    [Response: Re: 1. You used a < symbol which was interpreted as html. Use “& l t ;” instead. Fixed now. – gavin]

  94. PHEaston:

    Gavin: Re your response to 93. Not expecting you to print this – but thanks for the corrections and your willingness to allow some differences in viewpoint! If you don’t, then you have no debate. I realise that some text gets corrupted.



  95. Pat Neuman:

    By contrarians I meant the people who have views contrary to GHG emissions being the main cause of 20th-21st century global warming.

    From a new book (Thin Ice by Mark Bowden, 2005), it’s clear to me that increasing atmospheric CO2 has been driving global warming.

  96. Kenneth Blumenfeld:

    Re: 89:

    I agree. The language of the AASC draft makes the climate change debate seem more up-in-the-air than it really is. I note that it was drafted in 2001 and is overdue for an update.

    I personally wish that the AASC would drop any statement until the body of state climatologists has actually reviewed the relevant literature to reach their consensus. Again, these are for the most part, local climate experts, and maybe nature-of-the-data experts, but not global climate experts…with some exceptions of course.

    I feel the same way about NWS meteorologists working at forecast offices, television meteorologists etc. With some very rare exceptions, these are not people who have expertise about global climate change. The public may assume they are, but that, in my opinion, does not grant them any meaningful authority on the topic (though it is an authority they often exploit, nevertheless). The experts are the contributors to this site (among others), and these are the people who the public needs to be hearing from.

    The vast majority of climatologists and meteorologists do not understand the nuances of the climate change debate…they may only understand the barest elements–the shape of the hockey stick, a crackpot myth about it, but not the substantive details. I would actually venture to guess that many of the regular visitors to this site who are not trained in the atmospheric sciences have more knowledge about the state of climate change science than most operational and research meteorologists and climatologists. Changing that may seem useful, but it would require changing the atmospheric sciences to place global change as the centerpiece of the discipline…which it is not at present.

  97. Pat Neuman:

    No single person, agency or group in the U.S. is being held accountable for educating the public on what’s really happening to climate, and what needs to be done about global warming.

  98. Hank Roberts:

    “No single person, agency or group in the U.S. is being held accountable for educating the public” period.

  99. Pat Neuman:

    Re: 98.

    As a private citizen self-only, I was thinking along these lines for helping to inform the general public about global warming, not necessarily the same agency, but who else?

    The NOAA and NWS outreach program for educators

    … NWS provides awareness and preparedness materials to the education community to help inform the general public how to minimize their risk against severe weather events in their community. NWS material for the education community includes internet web sites, prototype interactive programs, publications and posters. The NWS has an outreach person in each local field office to work with local communities and educators to provide useful products and services. The NWS has recently produced a new web site for high school teachers and students. A middle school project, â??Xtreme Weatherâ?? is ready for testing in middle schools. A newly revised of the popular weather book, â??Owlie Skywarnâ?? has been printed and is suitable for elementary students. Collaborating with organizations such as the American Red Cross, The Weather Channel, the American Meteorological Society, the Environmental Protection Agency (EPA) and Department of Homeland Security allows the NWS to broaden its reach into local schools, communities and the general public.

  100. wayne davidson:

    I am more for immediate explanations, transmitted on a regular basis not as always with the occasional TV special, I believe that a climate segment should tag along with regular weather broadcasts, not in 5 seconds before a commercial break, but as a clear a way as explaining Doppler radar images. I think that most TV met specialists have a lot of talent, they can translate science journals just as much as interpret a weather forecast from GCM maps into simple every day lay words.. There is an insatiable appetite to learn about climate especially when extreme weather is happening, at that moment, the audience is starving for information. The biggest thing to do is to keep the public more informed than with a 3 day forecast, It would be a start fosterng a smaller audience for exaggerating skeptics, shedding the limelight to more complex issues does nothing but challenge the viewers to reason.

  101. Paul Dwiggins:

    Re #91, “The problem with the Sun being the cause is that we pretty much know all the Sun’s cycles on a human time scale.” How do you know this? This assertion appears to be contradicted in The IPCC report “Climate Change 2001: Working Group I: The Scientific Basis”. Section “Reconstructions of past variations of total solar irradiance” states “As direct measurements of TSI are only available over the past two decades it is necessary to use other proxy measures of solar output to deduce variations at earlier dates…However, direct solar proxies other than the sunspot number cover too short a period to reliably detect such a trend. Thus, it is not clear which proxy, if any, can be satisfactorily used to indicate past values of TSI.”
    Section “Natural Climate Forcing” states: “The estimation of earlier solar irradiance fluctuations, although based on physical mechanisms, is indirect. Hence our confidence in the range of solar radiation on century time-scales is low, and confidence in the details of the time-history is even lower.”

  102. Pat Neuman:

    re 100.

    True, regular weather broadcaster and educators could explain global warming to the public, then pass along the latest official global warming predictions and perhaps what the consequences could be. But, even if their advertisers allowed that to happen, the media has not been given basic information on global warming from official sources, not that I know of.

    I’d like to see comments to RC from media, and local and state gov employees and others about any advice in dealing with global warming which they may have received from official contacts in the fed gov agencies. Did they formally or informally ask for fed agency advise in dealing with the public on global warming? Any documentation on what was said?

  103. Eli Rabett:

    Continuing one of the parallel discussions that have broken out here, one can only evaluate the postings of Roger Pielke Sr. (and to a large extent Jr.) if you have an appreciation of the scientific “culture” of the State Meteorologists. With their intense local focus, they are often somewhere between uncaring and hostile to global climate effects, but as others have pointed out they are key nexus points for data gathering and dissemination (e.g. precipitation forcasts). Given the public prominence (the INTERNET is public you know) of these two, Michaels, Christy and others, I think this is something that has to be brought out.

    On the other hand, the “global climate community” (for example, GISS, Hadley Centre, etc.) has to work harder at showing how its work is relevant to the sub 1000 sq km scale that the State Meteorologist work at and making it clear how the data gathered at those scales are needed for global scale research. If you ask me, a lot of the pushback from Roger Pielke Sr. is a cry for attention to things he thinks important.

    I anticipate that all sides will shout at me that they are doing this, but, again obviously, at the sub 1000 sq km scale it ain’t working guys.

  104. Eli Rabett:

    Mea culpa, should have been State Climatologists in 103. I know, weather is not climate.

  105. joel Hammer:

    A big job of the “educators” would be to debunk the alarmists for global warming. The pro-global warming people never seem to attempt to debunk the crazies who argue in favor of global warming. Don’t they understand that crackpots are easy to debunk and then the whole idea of global warming looks suspect?

    For example, the NY Times ran articles this summer on Alaska melting and all. It was all blamed on global warming driven by CO2. No responsible person in the climatology community came forward to debunk global warming as a cause of this. Why not? Now, when I visit a site such as this:

    I am quite willing to believe the worst about global warming protagonists. Afterall, if global warming were real, they wouldn’t have the need to exaggerate, would they?

    [Response: We didn’t deal with that story specifically, but we have criticised unsupportable over-reactions, for instance, on Global Dimming or the hurricanes issue. We will continue to do so as things come up, however, in the same way that we can’t critique every occurence of a ‘contrarian’ argument, we can’t critique every piece where someone confuses climate change with weather. -gavin]

  106. Pat Neuman:

    re 105.

    I think the piece by the Alaska Climate Research Center that joel hammer referenced should be critiqued. The article is titled Temperature Change in Alaska: 1949 – 2004. Here is my quicky review (in parenthesis).

    The period 1949 to 1975 was substantially colder than the period from 1977 to 2004, (True)

    … however since 1977 little additional warming has occurred in Alaska with the exception of Barrow and a few other locations. (False)

    In 1976, a stepwise shift appears in the temperature data, which corresponds to a phase shift of the Pacific Decadal Oscillation from a negative phase to a positive phase. (Misleading, A shift to a sharper increase in global temperatures also occurred in mid-late 1970s).

    Synoptic conditions with the positive phase tend to consist of increased southerly flow and warm air advection into Alaska during the winter, resulting in positive temperature anomalies. (Misleading, larger increases in winter temperatures are a symptom of greenhouse global warming).

    Overall critique (Misleading).

  107. Pat Neuman:

    Friday, December 30, 2005 on PBS
    (Check local listings at

    This week on NOW:

    * Global meltdown. NOW goes inside the battle over global warming.
    What has scientists alarmed and why isn’t Washington listening? Find

  108. Jim Glendenning:

    “Scientists are not disinterested truth seekers,” according to David Goodstein, vice provost of Caltech and an expert on research ethics. “They are more like players in an intense, winner-take-all competition for scientific prestige and the resources that follow from that prestige.”…

    I wonder if any of you climate scientists would like to refute Mr. Goodstein’s assertions. In my opinion, as long as people see scientists as less than open-minded then they are less likely to accept scientific assertions about the approach of the end of the world.

    Also, the real argument is not so much about the science of AGW. (Although there are plenty of different ideas competing for attention.)
    The real argument is, that if GW is really due to fossil fuel burning, what can be done about it short of sending the modern world into a depression with a return to the living standards of the 1930s. That is why I believe the only way this or any other developed country can be convinced to start cutting back on fossil fuel usage is if it becomes clear that it will be to the country’s advantage both fiscally and for national security.

    It is all well and good to tell people that in a 100 years things are going to be very bad here. Most people are much more worried about paying the rent/mortgage, the utility bill, fueling up their car, and other such issues than they are about what will happen climatically in 100 years. It’s just human nature.

    But if you can convince them that energy conservation and new clean energy technologies will put money in their pockets and make them more secure, most reasonable people will listen.

  109. Pat Neuman:

    re 106.

    The article by the Alaska Climate Research Center (105.)
    says: … however since 1977 little additional warming has occurred in Alaska with the exception of Barrow and a few other locations.

    That is false. The difference in annual temperature from 1949, 1950s compared to 2004 was greater than 4.2 Deg. F for 9 of 18 stations, as shown in Table 1.

    Table 1. Temperature comparison for stations in Alaska

  110. Pat Neuman:

    re 108.

    On Truth, Fact, Values, Climate Change, and Doughnuts — A Guest Commentary

    December 29, 2005 – By Peter H. Gleick, the Pacific Institute


    Another fundamental difference between supporters of real science and pseudo-science is that real scientists are willing to change their minds in the face of sufficient and compelling contradictory evidence. Changing their minds is something supporters of creationism and intelligent design, or skeptics of climate change, seem unable, or unwilling, to do.

  111. James Annan:

    “Scientists are not disinterested truth seekers,” according to David Goodstein, vice provost of Caltech and an expert on research ethics. “They are more like players in an intense, winner-take-all competition for scientific prestige and the resources that follow from that prestige.”…

    I wonder if any of you climate scientists would like to refute Mr. Goodstein’s assertions.

    Actually, I’d like to reinforce it. But remember that “an intense, winner-takes-all competition” means that we are always looking for ways to make our mark by overturning (or at least modifying) the established status quo. When someone gets something wrong, there are usually plenty of others ready to correct them, and even the most sceptical would have to accept that this procedure has been stunningly successful in uncovering the truth across a vast range of fields in recent decades and centuries even though the individuals themselves are merely human with all the flaws that this entails. You are welcome to suggest any further improvements, of course…

    Climate research does not consist of men in smoke-filled rooms all conspiring to decide what “the consensus” will be (I don’t know, but strongly suspect, that the IPCC process sees its share of forthright discussion). But one can go too far in the opposite direction – anyone whose sole contribution is to criticise and denigrate, without making any positive contribution at all, is unlikely to be highly regarded and will find few are prepared to collaborate or help them. IMO it’s best treated as a friendly competition – we are all trying to uncover aspects of the truth, and are all trying to get ahead of each other. More like golf than boxing, perhaps.

  112. Kenneth Blumenfeld:

    Re: 106:

    I think it is fair to say “… however since 1977 little additional warming has occurred in Alaska with the exception of Barrow and a few other locations.” If you look at the map with the individual values (or at the table) for the full period you see significant warming at every station:

    If you then look at the later period, you see the significant warming is limited to a few stations:

    The Pacific Decadal Oscillation did indeed shift phases in the summer of 1976, which can be seen here:

    Here is a nice graphical display of what the PDO is (believed to be):

    I should also mention that the suggestion of a PDO signature in the temperature record does not in any way refute the possibility of a simultaneous global warming signature. They are different things.

    Since we both (Pat and I) live in Minnesota, let me provide a local example of “synoptic” explanations in non-competition with global warming explanations.

    After the winter of 1985-86, our winters in most of MN (and the Upper Midwest) became comparably tame. We began setting more warm-type records (daytime highs, and record warm “lows”). The benign winters continued into the mid 1990s. Then, it seemed the ante was upped; beginning with the winter of 1997-98, we have not merely broken records, we have shattered them. This continues. We have gotten used to bare ground in December. Our potential severe weather season has expanded on both the early and the late ends, our extreme precipitation and flash flooding season has expanded also. In my opinion, this is our very own, personalized global warming signal. No local experts have found a remotely compelling counter-argument. That is the large-scale explanation. On the synoptic scale, the Polar jet has spent more time to our north, we have had more days with warm air advection (i.e., southerly winds), and we have had fewer “strong” mid-latitude cyclones passing to our south…to name just a few “failed” mechanisms. One explanation (e.g., global warming) does not negate the other (e.g., synoptic conditions). And this whole long-winded bit was just to say that the folks at the Alaska Climate Research Center are not saying (or denying) what it appears you think they are.

  113. Sam:

    I am wondering if there has been any response to this piece skepticism by C. R. deFreitas of the Aukland NZ School of Geography and Environmental SCinece.

    Granted even though it is published by The Bulletin of Canadian Petroleum Geology, I am not qualified to judge it.


    [Response: Seems to be pretty poor stuff. From near the start: Contrary to the IPCC predictions, global temperature has not risen appreciably in the last 20 years. Most surface temperature data free from the influence of surrounding buildings and roads show no warming. Data from satellites support this. This is all wrong: T *has* increased (not sure why he says “predictions”); rural trends are similar to urban ones (here); satellites support the sfc record (here) and the models – William]

  114. Pat Neuman:

    re 112. Kenneth, you wrote: If you then look at the later period, you see the significant warming is limited to a few stations:

    I disagree with the Alaska Climate Research Center saying that … since 1977 little additional warming has
    occurred in Alaska with the exception of Barrow and a few other locations. That is false, according to the data that I found at the Western Regional Climate Center, at

    I added a table with annual temperature data at Alaska stations for 1977 and 2004, and differences to my: “A critique: Temperature Change in Alaska: 1949 – 2004 (updated)”, at:

    Please take a look at my critique which I updated this morning. Any additional comments that you may have would be appreciated.

  115. J. Sperry:

    Re 110 (and P. Gleick’s Dec. 29 article on ENN):

    This article repeats the fallacy that one must be an expert with an alternative theory before one points out another’s errors:

    “The proper response is to insist that the skeptics produce a reviewable, replicable scientific theory that can provide a plausible explanation for the mass of the evidence on climate change without invoking human interference. No climate skeptic has ever been able to produce such a theory”.

    The article also laments about those who “are locked into a certain way of seeing things, a world view that clouds their vision when presented with evidence that contradicts their beliefs and leads them to twist their interpretations and manipulate facts”. This sounds like some on either side of the debate to me.

    [Response: Not so sure about your point here. It is true that a criticism can be made of a piece of science (as described above), without having a better explanation at hand. However, it is also fair to point out (as Gleick does) that in fact there isn’t a ‘skeptic’ theory that provides a better explanation. -gavin]

  116. G. R. L. Cowan:

    Michael Tobis in comment 54 opines that “no one has come up with a reasonable way of testing which of these pressures dominate” — the pressure to overstate risks and the pressure to downplay them.

    But in the case of AGW risk, the question, “Who funds the funders” seems illuminating to me because the answer, to a very significant extent, is “fossil fuel consumers”. Because of large special tax revenues these consumers provide, funding agencies and the political sector that supports them have an interest in not hearing bad news about the effects of fossil fuel use.

    — Graham Cowan, former hydrogen fan
    boron as energy carrier: real-car range, nuclear cachet

  117. PHEaston:

    Re: Sam (113). I have learned one very interesting thing from your referenced paper. In Chapter 1 of the IPCC TAR, the following statement is made:
    “The fact that the global mean temperature has increased since the late 19th Century and that other trends have been observed does not necessarily mean that an anthropogenic effect on the climate system has been identified. Climate has always varied on all time-scales, so the observed change may be natural.”
    I have double checked this, and it is correct (Section 1.3.2, p.97). I do not repeat this to say whether I concur with it or not, but rather to highlight that the IPCC – often quoted in these pages as representing THE ‘scientific consensus’ – clearly does not in itself represent a concensus.

  118. McCall:

    Correction to link in #107

    Will be showing periodically over the next days

  119. Coby:

    re 117:

    The statement you quote from the IPCC is hardly controversial, rather it seems quite obvious. It does not therefore follow that the report “clearly does not in itself represent a concensus”. seems down at the moment so I can’t check the context of this remark, nevertheless, acknowledging that an observed change may be natural does not preclude assessing more evidence and concluding that it isn’t.

  120. Brian Jackson:

    Re: PHEaston (117)

    The quoted sentences can be found under the title “Detection and Attribution” here. The quote is indeed correct as far as it goes. However, the next sentence says:

    A more detailed analysis is required to provide evidence of a human impact.

    before a discussion of how a human influence can be detected. A little later it concludes:

    In this way the SAR found that “there is evidence of an emerging pattern of climate response to forcing by greenhouse gases and sulphate aerosols in the observed climate record”. Since the SAR new results have become available which tend to support this conclusion.

    So the quoted passage is simply saying that, just because the climate is changing doesn’t necessarily mean that it is due to human activities, which is trivially correct. It isn’t saying that climate change isn’t due to human activities, and so isn’t in disagreement with the IPCC consensus.

  121. PHEaston:

    Re: 120. I agree with your clarification. I bet that had one or two people sweating!

  122. joel Hammer:

    It is interesting to see that, just like the global warming skeptics, no data will convince the true believers (eg. The Alaska Climate center data). Every piece of data that contradicts global warming must be shown to be false or irrelevent or misconstrued by the people who understand the data best. For example, in a stunning display of political correctness, the cooling of Antarctica was declared irrelevent to global warming by the author of the study which documented this cooling. Unboubtedly he had expected to find Antartica cooling. I suppose this observation will be ignored or explained away as having nothing to do with global climate change.

    The fact that Alaska is not heating up and that Antarctica is cooling does not of course disprove global warming, but to ignore these findings is just bad science. A true scientist would recognize that anomalies (ie. Deviations from the expected) are NOT the enemy. They are opportunities to extend your understanding. Who knows. Maybe there are really important things we don’t understand about climate.

    Verily, there is little to choose between the antagonists in this debate.

    [Response: – William]

  123. Pat Neuman:

    re 122


    The article (2005) by the Alaska Climate Research Center (ACRC) states:
    … since 1977 little additional warming has occurred in Alaska with the exception of Barrow and a few other locations. …

    The ACRC statement above is false.

    I proved that the ACRC statement above is false in Table 1a. of my 30 Dec 30 2005 post to ClimateArchiveDiscussion, Subject: ‘A critique: Temperature Change in Alaska: 1949 – 2004 (updated)’, at:

    Table 1a was based on data from the Western Regional Climate Center (WRCC), which is located in Reno, NV. The WRCC supports a three-partner National Climate Services Program – the partners include: National Climatic Data Center (NCDC), Regional Climate Centers (RCC’s), and State Climate Offices. see:

  124. Brooks Hurd:

    Re: 107
    Pat, I watched the NOW program on PBS. The message that I got from that program was that all people who do not agree with the premise that AGW is responsible for climate change are funded by the oil industry. The reporter made this point over and over throughout the show even though only he and one of the people interviewed made this case.

    I was very interested to see Richard Alley showing off his ice cores in his freezer lab.

  125. Brooks Hurd:

    Reading through this thread, I was struck by the absence of discussion about the recent Hwang controversy (debacle?) Here is clearly a situation where a good dose of skepticism would have served the interest of science and Science.

  126. Pat Neuman:

    Re 124


    I haven’t seen the PBS NOW program, but I plan to watch it soon. I read a transcript of it yesterday. One can view some ice cores in a freezer lab at the linked to article, below.,1299,DRMN_15_4310949,00.html

    Might need to put the link together to get there?

    Earth’s uneasy breathing measured on Niwot Ridge
    Gases collected at 11,500 feet reveal nature’s responses to warming world By Jim Erickson, Rocky Mountain News
    December 13, 2005

  127. Eli Rabett:

    #117, 120 and 121. In 117 PHEaston artfully snips out a fragment from the IPCC TAR, creating an impression that is not supported (indeed essentially contradicted) by the complete piece from which it is taken. When Brent Jackson calls him on this in 120, Easton artfully tells us in 121 that he was just funnin’.

    Pat Neuman said in 51, “My wish is for writers here to be specific, not imply things or make insinuations which may cause others to make false assumptions about what they meant in their writings.” PH just told him not to bother.

    So the issue becomes should anyone offer any respect or credibility to Easton and his crew. I think not.

  128. Brooks Hurd:

    Re: 126
    Thanks Pat. The RMN article showed storage of ice cares, but not handling of the cores. The video of Alley in his lab showed Alley handling his ice cores.

  129. Hank Roberts:


    Richard Feynman told a national science teachers convention in 1966:

    “We have many studies in teaching, for example, in which people make observations, make lists, do statistics, and so on, but these do not thereby become established science, established knowledge. They are merely an imitative form of science … The results of this pseudoscientific imitation is to produce experts …. Learn from science that you must doubt the experts. As a matter of fact, I can also define science another way: Science is the belief in the ignorance of experts.”
    (The Physics Teacher, 7 September, 1969, 313-320)

  130. Coby:

    Re #129

    This is a nice quote and good advice, but it is for scientists in the expert’s field or others seriously studying a topic. If you are a climate scientist then absolutely you should not just believe everything you read in the journals of climate research, but if you are not knowledgable in the field and can not understand all the technical details that support an expert’s conclusion then you need to have a little trust, especially when all the experts agree. Absent some trust somewhere you will spend your life reinventing wheels.

    This gets to the central point of this RC article and what it means to be an intelligent skeptic. A true skeptic in the sense that Richard Feynman is advocating above will doubt the experts and search out the areas of ignorance BUT they will come up with the answers and corrections (or confirmations!) themselves and that is the spirit of science. The “septic” on the other hand uses sentiments like Richard Feynman’s above only as something to hide behind while offering no clarity, no conflicting evidence, no logic: just FUD.

    Unfortunately it is trivial to learn just enough to raise plausible sounding objections thus forcing uninformed onlookers to feel it is too complicated for them to decide for themselves. Once this is acheived the onlooker you are trying to manipulate is much more vulnerable to emotional or other irrational influences and a once severly one-sided scientific debate is now an even playing field.

  131. Dano:

    Unfortunately it is trivial to learn just enough to raise plausible sounding objections thus forcing uninformed onlookers to feel it is too complicated for them to decide for themselves. Once this is acheived the onlooker you are trying to manipulate is much more vulnerable to emotional or other irrational influences and a once severly one-sided scientific debate is now an even playing field. [link added]

    Well said sir. I hope you don’t mind me using it, Coby, unless you have an intellectual property copyright, or have inserted spyware into it :o) . If I could add just one thing: a phrase seen often used by contra/denialists, rather than ‘plausible-sounding objections’, is ‘serious questions’.

    Kenneth Blumenfeld’s students would do well to mark your phrase when scanning or Googling. In addition, the appeals to emotion is another clue.



  132. Coby:

    Thanks, Dano :) Feel free to use it, I believe I gave up any copyright claims by tacitly accepting (11) of RC’s Comment Policy anyway, though I make no guarantees about embedded spyware!

    Of course this tactic is greatly facilitated by the “sound bite” nature of news reporting in general and the media’s infatuation with the false objectivity of balance. That link is to an RC post, of course concerned with GW issues, but it is an affliction that crosses many journalistic domains.

    I do have a sense that the septics have lost a lot of ground this last year, having fewer and fewer plausible objections as the research seems to pour in. The issue has been cleverly hijacked though and it will be some time before the claims that the news is getting more dire because the “GW advocates” are getting more desperate will lose all credibility in a society so nicely conditioned to distrust all those “UN funded liberal scientists”

  133. Brooks Hurd:


    if you are not knowledgable in the field and can not understand all the technical details that support an expert’s conclusion then you need to have a little trust, especially when all the experts agree.

    Two points:

    1. Saying that all experts agree is hyperbole. I know of no subject upon which all the experts are in agreement.

    2. Saying that something is true because experts agree is a logical fallacy. Whether it is an appeal to authority or an appeal to popularity, it is a nevertheless a logical fallacy.

    Believing something because the vast majority of data supports that belief is rational behavoir.

  134. Coby:

    Re #133:

    Saying that all experts agree is hyperbole. I know of no subject upon which all the experts are in agreement

    I think this is itself a bit of a hyberbole. Depending on how specific or general the question is there are surely many things where all the experts are in agreement. Astronomers and the distance to the sun. Geologists and the approxiamate age of the earth. Cardiologists and the function of the heart…You get my meaning.

    For climate science and global warming, I grant you it is a hyberbole to say “all experts agree” absent a specific general topic. I would not hesitate to say that all experts agree the temperature is rising and has risen over the last century. After that we are talking about degrees of majority I suppose, each issue with its own consensus or controversy. My personal impression is that it is a fair statement that the large majority of climate experts agree that anthropogenic GHG forcing is the primary driver of the 20th century warming trend and this trend will very likely continue through the 21st century.

    Saying that something is true because experts agree is a logical fallacy

    I agree. But I did not say that. I said that faced with a consensus of scientific opinion and absent personal expertise one should have a little trust. I also said that absent some trust somewhere you will spend your life reinventing wheels but I should have said you will more likely spend your life walking.

    Yes, any group of experts could be wrong. But to people who are so quick and persistent to point that out only because they do not like the implications I say “put up or shut up”. It is not enough to say “we used to believe in ether” or “we don’t know everything” or “the models have flaws”, if there is a serious doubt investigate it, if there is an alternate theory present it, if there is a better model run it.

    I have looked at as much of the science as I have time and stomach for and I continue to follow it. It looks solid to me. I have also entertained quite a few contrarian arguments and 99% of them are obviously, seriously flawed. The 1% I keep in mind, but a one in a hundred chance that we are not in grave danger is no justification for “staying the course”

    Believing something because the vast majority of data supports that belief is rational behavoir.

    Agreed. Start here:

  135. Francois Ouellette:

    I’d like to come back to the core issue. I find your interpretation of Bertrand Russell utterly dishonest. When you say “If we relax the above-mentioned constraint requiring ‘all experts’ to agree (something never achieved in practice) to ‘the overwhelming majority of experts’ “, you distort what he said. Russell did not say anything about “relaxing” his statement, otherwise he would have said so. I understand that it is convenient for your own point of view, but you shouldn’t use a Bertrand Russell quote to support it if it doesn’t. The rest of your argument goes along similar lines.

    About Galileo: he was not an “an obscure scientist persecuted by an entrenched mainstream”. If you’re going to use him as an example, you should read a bit more about him. Galileo was NOT persecuted by the mainstream scientific establishment of his time. Galileo was a star all over Europe, exactly because he dared challenge the “consensus” about Aristotle, and by doing so opening the eyes of everyone.

    Galileo could have accepted what “an overwhelming majority” of experts were saying about falling bodies. If he had, we would have had to wait for another “sceptic” to learn that “the overwhelming majority” were wrong.

    Galileo was persecuted by the CHURCH, for very political reasons, because his thinking was seen as DANGEROUS, not scientifically, but socially. Also, he did not DEFY the establishment. He published what he thought was right, and when he did publish his “Dialogue on two world systems”, he thought he had the church approval. The Pope actually betrayed him, and let the extremists around him condemn Galileo.

    My own version of scepticism is that it is the best way to make good science. I am myself a scientist with 25 years of practice. Whenever I read a paper, I read it with a highly skeptical eye. Whenever I make an experiment, and the results almost agree with the theory, I use the “almost” to dig further. Sometimes there is a lot in the “almost”. Sometimes the entire theory falls apart, or you find some unexpected effect that has important implications. So when I see results on climate that “mostly” agree that GHG cause GW, I say we have to look at why they only “mostly” agree, and not “totally”. Are we missing something important (to quote Rumsfeld, things that “we don’t know that we don’t know”), are we being misled by appearances, were we biased in the first place? The same with consensus. If an “overwhelming majority” agree, but there is a single voice out there saying something different, I will listen closely to THAT voice (listen, not necessarily believe). It seems to me that the “consensus” argument is very dangerous in that regard.

    And yes, I agree with Feynman. Remember he led the enquiry on the first space shuttle disaster. What he found was that it’s the refusal to listen at contrarian points of view within NASA that was the main cause of the accident. There is a good lesson there.

  136. Maurizio:

    Skepticism has nothing to do with what the experts, lots of them, or few of them, or all of them, agree or disagree about in a particular field.

    Otherwise we fall back in arguing on the basis of authority, and if that were true, we would still be quoting Aristoteles like at the times of Galileo. Does anybody remember the troubles Nobel-prize-winnder Chandrasekhar had to go through before denting the “consensus” represented by Eddington (no less) at the beginning of the XX century?

    Skepticism is about asking for evidence. And as wisely suggested by Carl Sagan, extraordinary claims (like, “Humans are changing the planet’s climate”) do need extraordinary evidence

  137. Hank Roberts:

    Well, no. Feynmann showed that NASA managers had ignored actual failures happening repeatedly, and that they were ignoring the straightforward risk calculations done by the engineers.

    Would a one percent risk of abrupt climate change be too much? I think any scientist will say it’s too much. Any politician or public relations mouth will say it’s insignificant risk.

    NASA was lucky until they had to launch a schoolteacher — for a political window of opportunity — the first ever launch below freezing temperatures.

    They went one step further outside the design envelope, into unknown risk levels.


    Feynman’s personal appendix, here, is very brief and very clear:

    Take a spacecraft — this planet — far outside its past performance envelope. Climate scientists are trying to understand the risks. The politicians and business PR people are obfuscating and denying any possible risk could exist so they can go on pushing outside the envelope.

    Feynman said the engineering showed Shuttle risk was perhaps one percent — one failure in 100 flights, but

    “Official management … claims to believe the probability of failure is a thousand times less…. demonstrating an almost incredible lack of communication between themselves and their working engineers.

    “Let us make recommendations to ensure that NASA officials deal in a world of reality in understanding technological weaknesses and imperfections …. They must live in reality ….

    “For a successful technology, reality must take precedence over public relations, for nature cannot be fooled.”

    This is why the denial is so strong — because a one percent risk of losing the climate that made humans civilized is too much, and we’ve already taken the risk and are waiting on the outcome.

  138. Francois Ouellette:

    Since Feynman has lurked into this thread, here is a link to his commments on the space shuttle disaster :

    And here is another quote from the same speech as above on “What is science”:

    “When someone says, “Science teaches such and such,” he is using the word incorrectly. Science doesn’t teach anything; experience teaches it. If they say to you, “Science has shown such and such,” you might ask, “How does science show it? How did the scientists find out? How? What? Where?” It should not be “science has shown” but “this experiment, this effect, has shown.” And you have as much right as anyone else, upon hearing about the experiments–but be patient and listen to all the evidence–to judge whether a sensible conclusion has been arrived at. (…) I think we live in an unscientific age in which almost all the buffeting of communications and television–words, books, and so on–are unscientific. As a result, there is a considerable amount of intellectual tyranny in the name of science.”

  139. Pat Neuman:

    My Summary below is posted here to encourage additional people to post their comments to my questions at RC’s subject: Naturally trendy.


    Comment 84. response in RC Naturally trendy reads: But statistics is only so much, and there is, as you say, inappropriate ways and appropriate ways to apply statistics. … rasmus]

    Comment 91. in Naturally trendy reads: Do you think the procedure explained in 86. is an appropriate way to apply statistics … ?

    Comment 93. in Naturally trendy reads: I do, because it integrates historical data with current conditions. I believe large short-term hydrologic events do make it into the probabilistic outlooks also. It’s not perfect, but I do think it is a reasonable product.

    Comment in 94. in Naturally trendy reads: Although I understand that things can’t be perfect, I believe that professional hydrologists should try to adjust for inadequacies in modeling procedures and forecasts, which currently do not take account of the large amount of evidence showing that hydrologic climate warming has been happening in the Upper Midwest. …

    Please go to RC’s Naturally trendy to post your comments. Naturally trendy is at:

  140. Coby:

    Re #136

    Skepticism is about asking for evidence. And as wisely suggested by Carl Sagan, extraordinary claims (like, “Humans are changing the planet’s climate”) do need extraordinary evidence

    I think this is a very reasonable sentiment. Do you not find this extrordinary?:

    And this:

    Taken together with this:

    Makes an extraordinary case. Not the whole story by far, but it is the extraordinary evidence demanded and leads to all the rest of the data and research that confirms many times over that something extraordinary is happening.

    Now lets turn this same standard on those who remain unconvinced. Given the uncontroversial and well established physical principles of Greenhouse Theory, I believe it becomes an extraordinary claim to say that a 30% increase in CO2, the major persistent GHG, (please recall that H2O acts as a feedback and not as a primary forcing of temperatures), that an unprecedented in 650Kyr plus level of this important gas will not alter the climate. Where is the extraordinary evidence for this claim?

    I think it is also an extraordinary claim to say that every major scientific institution dealing with climate, ocean or atmosphere is wrong, not impossible, but extraordinary. Michelson and Morley were certainly making a similar claim that all of their colleagues were wrong and there is no ether but they had extraordinary evidence! Where is the sceptic’s extraordinary evidence?

    By all means, be sceptical, don’t take a stranger’s word for anything. But apply the same standard to all sides. Don’t give a free pass to authority figures, but don’t give one to that lone voice of doubt either, no matter how much romantic-underdog appeal that has.

  141. Francois Ouellette:

    RE #137

    Feynman’s findings can be interpreted in a number of ways! My point is that management did not see the evidence for a large risk of failure because it went against their belief. They collectively convinced themselves that the shuttle was safe, so no evidence would have convinced them otherwise because they did not look at it. I see much of that attitude in the climate debate, on both sides of the issue.

    My point is: it’s good to be a sceptic. Being a sceptic is the essence of being a scientist. Sceptic means: you don’t believe. Personnally, I have decided not to accept the argument that because there is a “consensus”, I should believe. This blog and others are useful to indicate which issues are contentious, but from there I usually try to go to the source and make up my own mind. I cannot even tell you at this point what my opinion is! It IS a very complex issue. There are a lot of data, and no, they don’t all point in the same direction. Just looking at a couple of graphs on Wikipedia is not enough! I’d say reading the whole of the IPCC TAR (not the summary) is a good start. There’s a lot of interesting stuff in there.

    As for the contrarians, I don’t necessarily BELIEVE them, but at least I LISTEN to them. They also have a lot of interesting things to say.

  142. Hank Roberts:

    > much of that attitude in the climate debate, on both sides

    When people see “both sides” and “debate” I think they’re not watching the science — they’re watching the audience. It’s misdirected attention. Capturing that attention is politics and public relations work.

    We’ve already given the climate a big input burning fossil fuels, among other natural inputs that we don’t know well — now, we’re like a bowler who’s already let go of the ball — leaning and twisting, in unconscious contortions that can’t influence the score that’ll come up when the rolling ball finally hits the pins.

    The audience has “sides” — nature doesn’t. Nor do the scientists who’re trying to pull out an understanding of what nature’s been doing and what people are contributing to what nature will be doing next.

    Maybe somewhere there is a fraud who’s faking scientific results — we saw the recent stem cell debacle. The real journals have to manage peer review, for the endeavor of science to work.

    There are plenty of pretend “science” sources out there — not reviewed, full of cherry picked “facts” used for public relations, picking anything to push their agenda. There, you’ll find “sides” clearly enough.

    If there’s been any miracle involved in civilization, I’d say the development of science has been that miracle. It didn’t happen over and over — for what, close to a hundred thousand years, through many different cultures from many different precursors, most cultures never got to the level of doing science. They’re forgotten. Ours did, somehow, and those who do science are the culture we all belong to, if only as audience members.

    Keeping science working is not (except for a few USA school boards) a debatable question on which people take sides, in the civilized world, I think. I think there’s the culture that values science _whatever_the_results_ and we’re it.

    We learn, or we don’t, to learn how nature works. Hard argument works in science — challenge, test, retest.

    In this climate area there’s also a lot of money at risk, and a consequent huge fog of audience contention, sides, debates, flat out blatant lying (google “always been an ozone hole” for examples, or any other claim you care to test for repetition without research basis).

    It’s not the scientists you’re watching when you see sides and debate outside the journals happening, it’s the audience you’re watching, and the public relations mouths yapping you’re hearing.

    What worries me most is that there are still a lot of people who’d just as soon do away with science to avoid the awkward and inconvenient facts it keeps turning up.

  143. Maurizio:

    Re #140


    First of all thanks for recognizing that the whole “Follow what the scientists say” is a misleading route as far as reasoned skepticism is involved.

    Let’s concentrate on the evidence then. And there comes another logical fallacy.

    I cannot demonstrate, nor anybody can, what something does NOT do.

    There are no known, and no unknown ways to show that “a 30% increase in CO2, […] that an unprecedented in 650Kyr plus level of this important gas will not alter the climate”

    The ball remains strictly on the side of people interpreting the current data as evidence of a climate extraordinarily warming and because of human activity.

    And all the more so as climate scientists were busy predicting a coming Ice Age just 30 years ago or so.

    [Response: This is wrong, as we’ve pointed out before: see #144 below – William]


    With respect to the “extraordinary” warming of the planet, it’d be nice to be presented with incontrovertible effects: for example, a change in the monsoon patterns, a remarkable contraction of the dry areas in the Sahara, sustained hurricane seasons in the South Atlantic, etc. AFAIK so it’s always been a case instead of shrinking glaciers and potentially changing oceanic currents.

    There may soon be no snowcap on top of Mount Kilimanjaro. But then, there was none 12,000 years ago either.

    [Response: Source?]

    Another example: is the Northwest Passage definitely usable by non-ice-breaking ships during the Northern Winter? And what is there to tell us when was the last time it had been so?


    Regarding the effect of human activity, given the fact that we cannot control at the moment the energies required for Planetary Engineering, the claim that we are changing the climate do remain extraordinary indeed.

    [Response: No, not really. Just about everyone – even skeptics like Pat Michaels – accept that we are changing (warming) the climate. Michaels disputes the likely future warming; not that there is current warming. You are way out on a limb. – William]

    What kind of “extraordinary evidence” would be required for that?

    Surely not just computational models or simple long-term statistical correlations.

    Both techniques deal with way too much uncertainties to be meaningful as “extraordinary evidence”. As reported on The Economist (recently converted to the Human-Made-Global-Warming cause):

    “the most important uncertainty, though, is that caused by a lack of enough good-quality, long-term, internally consistent data. Even the industrialised parts of the world, Europe and North America and their adjacent seas, have been studied properly for only a century and a half. Too much climate science relies on drawing conclusions from patchy information”

    [Response: The Economist isn’t a good source for climate science. See here for my take on that particular article – William]


    What kind of “extraordinary evidence” would be required then for a reasonably skeptical person to be convinced that humans are significantly changing the planet’s climate with carbon dioxide emissions?

    I simply do not have an answer for that at the moment. Suggestions welcome, of course.

    [Response: Errrm, well at least thats honest I suppose: you’re basically saying that nothing will convince you. The fact that the temperature is going up, as agreed by sfc, upper air and oceans; that models can reproduce the trend; and that this is unsual in the record we have is obviously not enough for you – William]

    And so IMNSHO the “science of climate change” remains an interesting, debatable hypothesis, more akin in Physics to superstring theory (a long way from being demonstrated) than to Einstein’s relativity (overwhelmingly shown a robust theory)

    Main consequence is of course that it all becomes a matter of debate, of policy, of politics. People (and scientists) must choose to believe (or not) in human-made-global-warming.

    I am all for free speech and free thinking, so go ahead, and campaign to sequestrate CO2 and reduce the use of coal as fuel

    But please don’t dress it up (yet) as “hard science”

  144. Hank Roberts:

    > predicting an ice age

    Bzzzt! Bogus. Bo-o-o-gus. Google is your friend here.

    Google for that claim. First three hits: two PR-politics sites and, ta-da, RealClimate.
    Look carefully for the difference between PR-politics and science, read footnotes:

    Science Has Spoken: Global Warming Is a Myth

    “… gradual planetary cooling, not warming, is next in the natural cycles driven by the sun. And records reveal cooling to be a far greater threat.” [yes, TODAY they say an ice age is coming]

    RealClimate » The global cooling myth …
    Every now and again, the myth that “we shouldn’t believe global warming predictions
    now, because in the 1970’s they were predicting an ice age and/or …

  145. Dano:


    This argument, IMO, isn’t quite right.

    It is quite testable (sciency stuff) to expect that increasing CO2 in the atmosphere should warm the planet (sure, there will be cooling in places).

    Why? Physical principles realized over a century ago by some Swedish chemist guy allow us to make this hypothesis. The evidence backs the hypothesis. In fact, there is sufficient evidence to call it a theory, which arguably makes it a hard science (physics – a hard science (it was really hard for me) – is the basic underpinning of meteorology, e.g.).

    Additionally, physical principles do not state that increasing CO2 will, say, cool the planet. This would violate physics. So, in this context, it would still be easily testable to expect that increasing CO2 in the atmosphere should decrease the planet’s temperature [please, no replies about meaninglessness of avg T]. Simple enough: where is the skeptic model that displays results confirming this hypothesis? Nowhere. Not one.

    There is no debate about competing scientific theories. There is no debate about differing results of modeling runs. There is no debate about evidence stating the planet is cooling in the elevated CO2 regime [higher than at any time in the past ~650K yr]. There is no debate about differing atmospheric CO2 measurements.

    Of course, the devil is in the details and the debate is about how much of the current warming is caused by man, and how much is part of a natural cycle. Period. The problem is that little bit about CO2 in the atmosphere, and that negates the tout that it’s all natural cycle. Why? Well, where is the skeptic model/result/evidence/film/.ppt/rune cast result/astrological chart that shows the elevated CO2 has played no part in the rise? Nowhere. Not one. So, we’re back to the details and amount of attribution [the skeptics/denialists/contrascientists want zero attribution], and the debate is about teasing out all the confusing signals from the biosphere, and the universal issue about having enough data.

    The biosphere will react when the planet warms. And the increased plant growth in temperate latitudes may serve to sequester CO2. The ocean may absorb some heat (evidence shows it has). Tundra will melt, releasing CH4 (evidence shows it has). Etc.

    There is plenty of stuff for quibblers to use to proudly state it all becomes a matter of debate, but to my mind this is a consequence of Google returning information, not wisdom.



  146. Coby:

    First of all thanks for recognizing that the whole “Follow what the scientists say” is a misleading route as far as reasoned skepticism is involved.

    No worries. Now at the risk of turning agreement back into disagreement, I really want to emphasis that I think that the kind of scepticism that you and I do agree is a good thing is not appropriate for anyone who does not study the issue. People who do not know the basics of climate theory and where the state of current research is and what has already been thought of and why it has been ruled out, and yet still insist that the case as a whole is unconvincing are not being sceptical, they are being denialists.

    [about sceptics showing CO2 does not raise temps.]

    Let’s concentrate on the evidence then. And there comes another logical fallacy.

    I cannot demonstrate, nor anybody can, what something does NOT do.

    I understand where this comes from, but you have taken it out of its strict logical context and slightly twisted it as well. You can’t prove a NOT(X) etc. But clearly I can demonstrate that action X does not have effect Y. I can drop a rubber ball on a piece of cement repeatedly and thereby demonstrate that this action does NOT shatter the concrete. You should be able to show through laws of physics and also via lab experiments that increasing CO2 in an atmospheric mix of gasses does not cause greater absorbtion of infrared radiation. It has certainly been demonstrated that it does.

    Of course the geophysical reality is much more complicated. That’s why we must look at history through the grubby lenses of proxy data and run models and observe everything we can think of.
    [Now before you list a “third” logical fallacy of mine, I would like to say for the record that you have not got me one one yet]

    What kind of “extraordinary evidence” would be required for that?

    Surely not just computational models or simple long-term statistical correlations.

    I don’t have much to add to the rest of your comments that I haven’t already said or others have already pointed out except that you are quite simply setting a standard that can in fact never be met. What else is there besides models, radiative physics, statistical correlations and observations of strange changes? (I am kind of intrigued that you are not impressed by melting ice, rising sea levels, rising temperatures, slowing ocean currents, warming ocean waters, all kinds of changes in flora and fauna but you mention “a change in the monsoon patterns” and “a remarkable contraction of the dry areas in the Sahara” as something “incontravertible”!)

    Ignoring that inconsistency, I think the kind of proof you are otherwise demanding requires multiple copies of our planet and some rather large timemachines – it ain’t ever gonna happen.

    So your answer is damn the torpedos, full speed ahead? That’s one hell of a gamble with something unique, priceless and not yours.

  147. Hank Roberts:

    Here are a couple of examples, I think, of people being good skeptics.

    Many will recall last year the sudden spread of the assertion that 90 percent of the world’s glaciers are actually growing.
    One person checked, it’s bogus (although “90%” is still being repeated as a fact).

    Skepticism at work, good examples:

    George Monbiot » Junk Science
    By George Monbiot. Published in the Guardian 10th May 2005 …
    [Claim of growth of] 555 of all the 625 glaciers under observation by the World Glacier Monitoring Service … So last week I telephoned the World Glacier Monitoring Service and read out Bellamyâ��s letter.

    Effect Measure: Bad typing and bad science
    Bellamy’s cited source for the glacier “facts” was the World Glacier Monitoring
    Service. Monbiot phoned the Service …

  148. joel Hammer:

    As a skeptic, I would like to know:
    1. What is the lag time between an increase in CO2 in the atmopshere and a rise in global temperature?
    2. If “we” (You better count the several billion people in Asia here, not just a few hundred million people in North America) stabilized the amount of CO2 in the atmosphere today, how much more warming would the Earth experience?
    3. Since the North Pole and Greenland are melting right now, according to the meanstream opinion, how will limiting future increases in CO2 emissions prevent climate catastrophe? We already have severe climate change (drought, flood, hurricane, unnaturally warm weather, permafrost melting, etc.), according to mainstream opinion.
    4. Is there any scenario wherein atmospheric CO2 will be reduced in the next 50 years? If we accept the fact that our current warming trend, with melting of the arctic and Greenland leading to massive floods, is due to the current level of CO2, why bother with modest attempts at CO2 emission reduction?

    It is obvious that the Kyoto proponents don’t believe that we are experiencing severe climate change due to the current level of CO2. If they did, their support of such modest reductions embodied in the Kyoto treaty just wouldn’t make any sense. So, if they are skeptics, can you blame me?

  149. Coby:

    1. What is the lag time between an increase in CO2 in the atmopshere and a rise in global temperature?

    Hopefully you will get a more qualified respondent, but my understanding is that there are in fact still several decades of warming “in the pipeline” so to speak. This is due mostly to the time it takes the ocean temperature to rise and a new equilibrium to establish after the imposition of an energy imbalance.

    2. If ..[we].. stabilized the amount of CO2 in the atmosphere today, how much more warming would the Earth experience?

    I think I have read that another 1oC or so is pretty inevitable.

    3. Since the North Pole and Greenland are melting right now, according to the meanstream opinion, how will limiting future increases in CO2 emissions prevent climate catastrophe? stopping the melting..? Why is that hard to understand?

    4. Is there any scenario wherein atmospheric CO2 will be reduced in the next 50 years? If we accept the fact that our current warming trend, with melting of the arctic and Greenland leading to massive floods, is due to the current level of CO2, why bother with modest attempts at CO2 emission reduction?

    Obviously we want to slow and eventually stop the changes that cause these negative consequences. All these rhetorical questions seem to suggest there is only “good” and “bad” and no degrees in between. The point of action now is to stop a bad situation from getting worse. What is the point of this “my hand already hurts why should I remove it from the stove” reasoning?

    Your question about scenarios seems to indicate you don’t understand what a scenario is. It is simply an imagined future trend of GHG emissions, so yes of course there is such a scenario where CO2 is reduced in the coming decades: the world stops all fossil fuel burning emissions within one or two decades. Such a scenario was not presented in the IPCC report because it clearly is extremely unlikely.

    It is obvious that the Kyoto proponents don’t believe that we are experiencing severe climate change due to the current level of CO2. If they did, their support of such modest reductions embodied in the Kyoto treaty just wouldn’t make any sense. So, if they are skeptics, can you blame me?

    Kyoto is a political issue. The discussion of scepticism on this blog is about the science.

    It is absolutely pointless to discuss Kyoto or any mitigation action proposals with someone who has not yet acknowledged that climate change is real and human caused and action of some kind is necessary. When someone raises the spectre of Kyoto’s shortcomings in a discussion of climate science it can only serve to obfuscate any serious discussion.

  150. Pat Neuman:

    re 148, 149

    I recommend:

    Hansen, J. 2005. Is There Still Time to Avoid “Dangerous Anthropogenic Interference” with Global Climate? A Tribute to Charles David Keeling (5.5 MB PDF). Presentation given Dec. 6, 2005, at the American Geophysical Union, San Francisco. 50 p

    Also see:

  151. Pat Neuman:

    Until Christy has “done the homework”, those allowing his statements to be published are doing an unfortunate disservice to the public and world environment for the future.

    According the NewsTrack link below, John Christy, director of UAH’s Earth System Science Center, said: “It just doesn’t look like global warming is very global,” … “The carbon dioxide from fossil fuels is distributed pretty evenly around the globe and not concentrated in the Arctic, so it doesn’t look like we can blame greenhouse gases for the overwhelming bulk of the Northern Hemisphere warming over the past 27 years” he said. “The most likely suspect for that is a natural climate change or cycle that we didn’t expect or just don’t understand.”

  152. Maurizio:

    Re: The original text (William’s?), Dano’s
    145 and Coby’s #146

    This is a posting about methods more than materials

    You do have me worried guys as it appears there are huge misunderstandinds about the basic tenets of the scientific method (including skepticism).

    Is nobody familiar with the Skeptic Society (

    Let’s examine what you’ve been suggesting (as method of skepticism), and why it is so wrong

    (a) Is it logical, wise, appropriate (and scientific) to rely on what the scientists say, and forego skepticism of what the scientists say, as suggested in the original text of “How to be a real skeptic”?

    No. That would be like “leave science to the scientists”, not much different from “leave astrology to the astrologers” (i.e. the rest of us suckers will just have to gobble up whatever the astrologers say).

    And plenty of people (including scientists) pretend to do scientific work that isn’t (Gould’s The Mismeasure of Man is as good a collection of that as any)

    (b) Is it logical, wise, appropriate (and scientific) to “put up or shut up” and sheepishly follow the latest scientific fashion unless one has some alternative explanation, as suggested by Dano at #146?

    Again, no. For example, I do not have an alternative explanation for Feng Shui: why should that prevent me from being skeptical about having to move about the furniture according to imperscrutable “energy fields”?

    And in hindsight, the fact that there was no alternative theory in the mid-XIX-century did not make the existence of an all-pervasive celestial ether any more plausible

    (c) Is it logical, wise, appropriate (and scientific) to “put up or shut up” and sheepishly follow the latest scientific fashion unless one has “studied the issue”, as suggested by Coby at #147?

    By all means, another resounding “no”. I have not studied Homeopathy in great details, and am not following the “state of current research”. Does that mean I have to believe that my health would improve by ingesting chemical solutions so diluted that (at best!) a handful of the original molecules would be present?


    In general, why do you people have so much trouble with skepticism “per se”? How can anybody do anything properly scientific without a skeptical frame of mind? And is it really necessary to be so (hyper-)defensive about human-induced global warming?

    Any and all scientific theories and models must be able to pass some sort of a threshold before being “accepted”.

    I did mention superstrings in physics as a good example of what is not (as yet) a strong scientific theory. It explains lots of physical phenomena but has not been “demonstrated” but with circumstantial evidence.

    In other words, would any supporter of string theory feel offended if I were to say I am skeptical of their models being the underlying basis of reality? Of course not (I hope so!). All people involved are aware of the current limitations and the search for evidence one way or another is not a bit less enticing for that

    There is a debate about string theory. That doesn’t mean they’re rubbish


    I have gone into great detail about global warming, and about its human-induced part. I have described both as “extraordinary claims” and described what “extraordinary evidence” would convince me of the former.

    I have even admitted that (as yet) I do not know what “extraordinary evidence” would convince me of the latter (and no, that does NOT mean that “nothing will convince me”; last time I have checked, it was up to the researcher to find a convincing way to demonstrate their findings)

    It would be interesting to know what convinced you of the “reality” of human-induced global warming

    [Response: You appear to have completely misunderstood the point of the post. The point was to demonstrate that nobody has any problem with scepticism ‘per se’ – what there is a problem with is simple contrarianism disguised as ‘scepticism’. Nobody is asking you to trustingly believe anything just because we say so. The scientific consensus on this issue has arisen because of an increasing body of evidence (the clear signs of global warming (oceans, land, ice), the radiative properties of the undoubtedly anthropogenic changes in atmospheric composition, the match of numerous diagnostics between model results and observations – only if anthropogenic effects are included). There are continuing uncertainties in many aspects of the science (related to aerosols, or the exact value of the climate sensitivity etc.), but they do not negate the likelihood of continued warming if GHG levels continue to rise. I agree that this might seem an ‘extraordinary claim’ – but there are clear physical principles to support this, including experimental data, observations and modelling – something clearly not true for homeopathy or Feng Shui. The test of any scientific theory is its ability to make predictions – model projections made in 1988 did a good job of matching the subsequent temperature evolution, models predicted the cooling to be expected due to Mount Pinatubo, they have correctly hindcast the cooling of the stratosphere, the warming of the oceans, and the temperature evolution of the 20th century. I would indeed find this (and much more evidence that we could get into) pretty extraordinary if it was in fact not a good approximation to what is happening in the real world. There is never absolutely proof in Earth science, but the balance of evidence is certainly heavily weighted to the reality of human induced global warming. – gavin]

  153. Maurizio:

    And now a posting more about the details of the topic at hand

    Re: William’s response to #143, Hank’s 144, Dano’s
    145 and Coby’s #146

    1. About past predictions of coming ice ages

    First of all, the fact that scientists in a particular field were “wrong” in the past does not mean they’ll always be wrong. It just means their next set of statements must be quite accurate to recover credibility

    [Response: Coby has answered many of your points below. I’ll repeat on this one, since its my speciality: your “fact” isn’t a fact: its wrong. You are the victim of septic propaganda and inaccurate press reports. Fortunately the truth is available: see – William]

    Second, the problem here is that the contemporary climatologists of the IPCC are pushing for policy changes in society. In that respect, the fact that (rightly or wrongly) society was misinformed in the 1970’s is important indeed. Policies are based on consensus, after all

    [Response: You’re wrong here too. The scientists and the IPCC stick fairly strongly to science. RC, for example, does its best to avoid policy – William]

    2. Kilimanjaro’s 12,000-year-old snows


    etc etc

    Unless of course it’s another case of the lay press overtaking what the scientific journals are saying?

    [Response: Not convincing. The first just says its a 12kyr core. That doesnt mean that there was no snow there 12kyr ago – just that the usable record doesn’t go further. The second is more specific, but I wouldn’t trust it not to be garbled. It was cold 12kyr ago – – William]

    3. About The Economist’s view that climatology is based “on drawing conclusions from patchy information”

    William: It’s hard to comment to statements like “The Economist isn’t a good source for climate science”. Sounds elitist at best. Your blog appears to indicate that you’re stuck in the right-left-wing categories of present-day USA. You also assume that the authors on The Economist are “economist-types”: that is akin to suggest that their rubbish collectors have a PhD in economic liberalism, just because they work at the magazine

    That said, you are right in noting that if the folks at The Economist can’t be convinced, there are huge troubles ahead for the “let’s stop producing CO2” people

    4. About global warming vs. human-induced global warming

    Is it really that difficult to distinguish those 2? I did indeed describe what would convince me that extraordinary global warming is going on at the moment: something more tangible than “the temperature is going up”. Something like an incontrovertible change brought upon us by that increasing temperature. Why e.g. have the monsoons not shifted? Is that not a valid question to ask?

    Do I really have to explain why that is different than measures of shrinking glaciers, and (patchy) measures of ocean currents?

    5. About “So your answer is damn the torpedos, full speed ahead?”

    Uh? didn’t I write “I am all for free speech and free thinking, so go ahead, and campaign to sequestrate CO2 and reduce the use of coal as fuel. But please don’t dress it up (yet) as ‘hard science'” ??

  154. Coby:

    Maurizio, you are right that a good sceptic is unafraid to ask the questions. But they need to listen to the answers and you have obviously not listened to the very clear evidence William showed you or you would not continue to think that a large consensus of the climate science community was urging action to avoid an ice age in the ’70’s.

    Statements like “The Economist isn’t a good source for climate science” sounds like common sense to me, hardly elitist. Real Climate is not a good source for economics either. No put downs there!

    Is it logical, wise, appropriate (and scientific) to “put up or shut up” and sheepishly follow the latest scientific fashion unless one has “studied the issue”?

    I don’t know if you are very young and overly proud or what, but, with a small substitution: yes absolutely, it is logical, wise and appropriate to heed the advice of experts unless one has studied the issue.

    5. About “So your answer is damn the torpedos, full speed ahead?”

    Uh? didn’t I write “I am all for free speech and free thinking, so go ahead, and campaign to sequestrate CO2 and reduce the use of coal as fuel. But please don’t dress it up (yet) as ‘hard science'” ??

    Yes, but I took that (perhaps incorrectly) as “you have fun advocating, I’m gonna wait this one out”. Which in the domain of climate change mitigation means “full speed ahead”. And I reiterate, the longer you are insisting on some undefined incontravertible evidence before ceasing actions that by all evidence will drastically alter our climate, the worse odds we have in this irresponsible gamble where future generation’s ability to thrive is at stake.

    The rest is going around in circles except for your offer to explain the high stock you would put in a change in the monsoons. Why is that so much more convincing than:

    – glaciers all around the globe melting
    – arctic sea ice declining:
    – ancient permafrost melting
    – coral reefs bleaching and dying
    – hurricane intensity increasing

    and many other anecdotal and regional reports of climate change that are out there. What is special about the Sahara desert and the monsoons?

  155. Dano:

    Maurizio wrote (current 152):

    In general, why do you people have so much trouble with skepticism “per se”? How can anybody do anything properly scientific without a skeptical frame of mind?

    First, “you people” isn’t a good start. Second, no one here has a problem with skepticism (as Gavin said).

    What _I_ said wrt your second sentence I italicized was that you people – the septics – (note the spelling) have no properly scientific anything. Nothing. Nada. You people can’t argue your scientific position because there is none; just saying something over and over doesn’t make it so.

    There is nothing that shows today is part of a natural cycle and thus nothing to worry about – no attribution here, therefore no tobacco-like lawsuits, move along now – and I challenge you people to take your properly scientific skepticism, develop a testable hypothesis, collect some data, analyze it, write it up, and let us know what you found. When there are some results out there, then a model can be built based on physical principles and the data you and others collect can be fed into it and the model to try to get an idea of what is happening.

    As the CO2 levels in the atmosphere are unprecedented in likely the last ~650 K yr, I’m sure a lot of folks will be very interested in your results. I’m sure there is a lot of funding out there for research to show this is just a natural cycle. If you need some help writing up the grant request, let me know.



  156. Hank Roberts:

    Applauding Gavin’s response, at the bottom of 152, beginning
    > [Response: …

  157. Maurizio:

    I clearly posted a comment about the METHOD of skepticism and Gavin replied about the MATERIALS of human-induced global warming. And just read Dano’s contribution (written, perhaps, without reading my comment in full) to understand what I mean when I say that some people DO have problems with ANY skepticism

    May I assume then that all my points about skepticism, the Skeptic Society, etc are still unanswered?

    Not to mention the fact that I tried to move the “70’s Ice Age” debate from the incorrect reporting about Climate Scientists at the time to the obvious consequences at a social level for the huge misunderstandings propagated by Newsweek, lots of popular scientific press, National Geographic, (and may I dare say, very little wisdom in some scientific articles’ titles).

    Let’s try again


    Is anybody willing to take up my “monsoon” challenge?

    What’s so wrong in asking for incontrovertible evidence to global warming?

    Everything else we do have (“glaciers all around the globe melting; arctic sea ice declining; ancient permafrost melting; coral reefs bleaching and dying; hurricane intensity increasing”) MAY be interpreted as evidence of (unprecedented/unnatural/runaway) global warming, and is COMPATIBLE with the idea that the world is getting extraordinarily warmer…but is there really any serious scientist out there that says “unprecedented/unnatural/runaway/extraordinary global warming” is the only way to interpret those data?

    For example: how does our current CO2 level compare to, say, catastrophic events in the past? What was the CO2 level, and the yearly increase in the atmosphere, when supervolcanoes were making the Deccan Traps? Is there evidence for coral bleaching at the time?

    It would be all very different if we were to witness a clear, unprecedented change in any weather pattern

    (The people at The Day After Tomorrow clearly understood that point…they didn’t depict a little less ice here, a little more sea there, with a dead coral in-between: they could only justify the disaster with continent-size temperate-area “hurricanes”)

    And by the way…I thought the South Atlantic hurricane were that “clear, unprecedented change” (how’s that for being skeptical but not asking for the impossible?), but unless there is a couple of sustained seasons, my jury will still be out.


    Likewise, the models appear to indicate that there is a strong human-induced change in the climate. Obviously I am not contesting that

    But no model, and no statistical correlation, can be enough to justify the acceptance of what remains an extraordinary claim (extraordinary, as already indicated, because we do not control the energies for planetary engineering)

    It would be nice/interesting/precious/indispensable to have something else too, where to base one’s conclusions upon. Is there?


    It’s rather unfortunate that Global Warming is usually presented just as an increase in temperature. If something extraordinary is happening, more than one extraordinary consequence SHOULD be out there for all to see

  158. Pat Neuman:

    re 157 Minneapolis is currently experiencing an unprecedented warm weather pattern, as are many other locations throughout the Upper Midwest. Meteorologists on TV stations are asking what the heck is going on. Meteorologist in the federal government continue their silence, claiming that climate change is much too complicated and controversial for their involvement in attempts to help the public understand what’s happening. Climatologists funded by state agencies continue to be silent about this deadly subject, leaving the subject entirely to experts in climate change, who ever or where ever they might be. Climate change continues to be a joking matter in Minnesota.

  159. Hank Roberts:

    > asking for incontrovertible evidence ….
    You need a source you trust beyond doubt, to get that, don’t you?

    > how does our current CO2 level compare ….

    You can look this up — and decide whether you trust the answers you find, after reading carefully. But for example —

    I tried Google just now using your words and found this almost immediately:

    From which I’ll pull a bit, but urge you to go to the source and read:

    “The global warming of 55 million years ago, known as the Paleocene/Eocene Thermal Maximum (PETM), emerged in less than 5,000 years, an instantaneous blip on geological time scales (the researchers indicate that 5,000 years can be considered an upper limit and they believe the warming could have unfolded much more quickly than geological records can show them).

    “In the paper, the authors note that modern carbon dioxide input from fossil fuel sources to the earth’s surface is approaching the same levels estimated for the PETM period, which raises concerns about future climate and changes in ocean circulation. Thus they say the Paleocene/Eocene example suggests that human-produced changes may have lasting effects not only in global climate, but in deep ocean circulation as well.

    …. “The case described in this paper may be one of our best examples of global warming triggered by the massive release of greenhouse gases and therefore it gives us a perspective on what the long-term impact is likely to be of today’s greenhouse warming that humans are causing.”

    But don’t trust me or simple summaries. Look this up and consider the sources.

  160. Tom Fiddaman:

    Re 148

    It is obvious that the Kyoto proponents don’t believe that we are experiencing severe climate change due to the current level of CO2. If they did, their support of such modest reductions embodied in the Kyoto treaty just wouldn’t make any sense. So, if they are skeptics, can you blame me?

    This doesn’t follow at all. Kyoto is a compromise, not a mandate imposed by GW believers. That it exists at all is due to the strong urgency felt by some, in the face of US resistance. It’s watered down by the need to bribe incumbents to participate, not by nonbelief. And in any case no one expects to be experiencing severe climate change yet – it’s about the future.

  161. Dano:

    RE current 157:

    What’s so wrong in asking for incontrovertible evidence to global warming?

    There’s nothing wrong in asking for it. This is planet earth, however, and verrrrry few things are incontrovertable. It’s just not how things work. Science is about likelihoods, not incontrovertable facts. For example, you may ask for incontrovertable evidence that the planet is 4.5 BYO. We don’t have it. But we operate on the likelihood this is true. Oil drillers don’t ask for incontrovertable evidence before drilling – they take the info from their geos and form likelihoods and work from that.

    It would be all very different if we were to witness a clear, unprecedented change in any weather pattern

    There’s nothing wrong in wishing to witness it. This is planet earth, however, and verrrrry few things are clear and unprecedented.

    t’s rather unfortunate that Global Warming is usually presented just as an increase in temperature.

    Correct, except that it isn’t. A simple Lexis-Nexis search should disavow you of that assumption. Maybe that was true 5 years ago, but not today. Check it out.



  162. Hank Roberts:

    One big question is the “sensitivity” — how much temperature change happens with a given change of greenhouse gases.

    I _think_ I can paste in Google Scholar links and they’ll work for others. I’ll try here.

    Here’s one cite for an estimate of sensitivity — it’s the range of uncertainty that’s worrisome, because even the low end is not much below 2 degrees, if I”m reading it correctly — (PDF, or view as HTML):

    Here are the search results for the 48 papers that reference the one above — simply reading the titles and brief Google search output will give a fair feel for this.

    But I defer to the climate scientists to comment on the science. I’m just pointing to how to look for information that may at least help us nonscientists ask intelligent and informed questions, by reading up a bit first. I’m reading these …

  163. Hank Roberts:

    P.S. — the above is an example of how I look for info before asking questions. If you want to discuss the _content_ of the example, there’s an active thread for climate sensitivity here:

  164. Pat Neuman:

    Author of 157 said: “It would be all very different if we were to witness a clear, unprecedented change in any weather pattern”. I replied (158) that Minneapolis and the rest of the Upper Midwest is currently having an unprecedented warm weather pattern.

    Annual Temperaturess at Minneapolis (1820-2005, 126 years of record.

    1. With 2005 annual temperature, a new highest ten year average temperature (46.6 F, 1996-2005) has beaten the old high ten year average (46.4 F, 1930-1939) by 0.2 F. See:

    2. 2005 was the eighth year in a row with above average annual temperatures, the longest warm streak in 126 yrs of record. Previous high number of consecutive above normal annual temperatures was seven set in 2004, …

    3. January of 2006 may be starting off with the warmest temperature pattern of record for this early in the year. What are the meteorologists and state climatologists saying about this. Nothing that might be getting on TV or radio to the public. Most people in Minnesota this string with no end of mild winters. Pay back time will be progressively hotter and more humid summers for years, decades, centuries … ahead.

    4. Snowmelt runoff studies show strong trends for earlier spring snowmelt runoff in the Upper Midwest.

    The weather/climate pattern going on now here can be called rapid hydrologic climate change in the Upper Midwest.

  165. Pat Neuman:

    re 164

    Correction, should be 186 years of temperature record at Minneapolis.

  166. joel Hammer:

    It is easy being a skeptic because so much nonsense is published about global warming. The real scientists don’t debunk the junk, so the skeptics do and convince people like me that there is great exaggeration about the effects of changing CO2 from 280 ppm to 360 ppm. Anybody care to remember the great drought in the Sahel, which was taken by many as due to human induced global warming? Or, shall we just move on?

    Same old pattern. Alarmists look at the short term and declare disaster a’coming. More sober people take the long view and say this has all happened before.

    Time goes by and the problem just fades away but the alarmists find something else to worry about.

  167. Hank Roberts:

    We have to remember — weather is not climate, and vice versa.

  168. joel Hammer:

    My favorite professor in school, who was a real skeptic and was proved right in some very important ways years down the road, when he was told he was going against expert opinion, snorted and said:

    “Experts? Those are the guys who tell you we used to make mistakes, but, we don’t make mistakes anymore.”

    Guys, listen to yourselves.

  169. Dano:

    Although weather data eventually become climate data, Hank.



  170. Lloyd Flack:

    It is much easier to have incontrovertible evidence of trends and states than it is to have incontrovertible evidence of causal connections. To get the latter one generally does experiments where one can control the conditions. If all the conditions except one are the same in two cases and the outcomes are significantly different then one can reliably infer that the changed condition caused a change in the outcome. We can’t do such an experiment on climate change so we have to take other approaches.

    We have to answer three questions. Has there been global warming over the industrialised period? Have greenhouse gases increased over this period? If there has been global warming and greenhouse gases have increased has the increase in greenhouse gases cased the warming?

    The warming trend is small by comparison with the noise in the data. Nevertheless we can reliably say that the World has been warming. We can extract the signal from the data. Furthermore it has shown up in too many data series at too many places – surface temperatures, Tropospheric temperatures, oceanic temperatures, glacier retreat. Since the Tropospheric data was reexamined and the ocean temperature trend analyses were made the case for global warming became incontrovertible.

    The glacial cores provide incontrovertible evidence of anthropogenic increases in greenhouse gases.

    The problem is with getting incontrovertible evidence that the greenhouse gas increases have caused a large proportion of the temperature increases.

    Physics tells us that if we increase greenhouse gases we will warm the planet. The question is by how much? Will feedbacks increase or decrease the warming? For anthropogenic global warming to be negligible we need to have negative feedbacks nearly as great as the warming effect itself. How do we find out whether we have positive or negative feedbacks and how big are they?

    I do not think that we can conclude just by looking at the temperature data that the temperature increase over recent decades does not have a natural cause.

    All we can do is create mathematical models incorporating the major forcing variables. They have to be compatible with what we know of the physical processes involved and with the historical record. While these models have many adjustable parameters most of them seem to give similar results. Rather like the way you can often fit various regression models with different parameters which end up giving almost the same predicted values. I suppose it’s a bit like creating models of processes in stars.

    The fact that multiple models give similar predictions and fit the historical data reasonably well suggests to me that the predictions are likely to be reliable ones.

    No one has created a model using known physical process and structures that does not show a high sensitivity to CO2 concentrations. Of course something could be going on that we don’t know about that would reduce the effect of increasing CO2. But we have no reason to believe that such a process exists and so by Occham’s Razor we reject such speculations.

    So the preponderance of evidence is that a major part and probably most of recent global warming is due to anthropogenic increass in greenhouse gases. Yes, it is concievable that we have missed a major feedback process that would eliminate most of the effect of increasing CO2. But there is no reason to believe that we have. It is up to greenhouse skeptics to come up with concrete possibilities rather than make hand waving claims about unspecified natural cycles. What are these cycles and what is the evidence for them? The existing models are compatible with the data and do not need any unknown processes with major effects

  171. Pat Neuman:

    re 164 165

    11 Jan. 2006
    History and Climate Change at Minneapolis, MN, and Wisconsin

    You may view the article above, which shows 1820-2005 annual temperatures at Minneapolis, by going to the public Madison Independent Media Center website, at:

  172. Coby:

    #170 – Lloyd Flack

    Very nicely written!

    Of course something could be going on that we don’t know about that would reduce the effect of increasing CO2. But we have no reason to believe that such a process exists and so by Occham’s Razor we reject such speculations.

    (You mentioned what I am about to, but I wanted to pull it together with the above quote)

    Not only does one need some unknown process whereby CO2 is prevented from warming the atmosphere, but sceptics of AGW need another unknown process that is then driving an alledgedly natural warming that we do in fact observe. I think the need for one major, but completely undetected, factor would put the ball well into the sceptics court to come up with a theory. But having two such unknowns makes it very difficult to even take the notion very seriously.

    (Considering the unique case of climate science and economic implications, it behooves us as global community to check it out anyway. But I think we have.)

    CO2 *should* warm the atmosphere. CO2 is going up, the temperature is going up. This simple reality is why I consider the onus for extraordinary evidence to be much more on the denialist’s side of the debate. Besides, there really is alot of extraordinary evidence already soundly behind AGW theories.

  173. Maurizio:

    Pat (158, 164): A series of slightly-warmer winters can not be counted as extraordinary evidence of a change in weather patterns. What happened between 1930 and 1939, and what happened in 1940 to break the series of highs? And we are talking .2F, surely that’s not enough to make flowers appear in January where 20 feet of snow was the norm?

    Hank (159): That study is quite re-assuring, actually, as plants and animals thrived after the PETM. Also, Wikipedia in its infinite wisdom appears to suggest the culprit was massive methane release, not CO2.

    Somebody should advocate the prohibition of using beans as foodstuff! (joke)

    Dano (161): Is it really that much to ask for the ONE weather pattern that has changed due to “global warming”?

    Joel (166): I agree wholeheartedly. If only the Climate Science community would learn to differentiate itself from the “alarmists” and scaremongerers!

    If Human-induced Global Warming is found out to be a mistake like Phrenology (only, more honest), the impact on Climate Science and science as a whole would be very hard to recover from

    Lloyd (170): I could get along with the statement that “the preponderance of evidence is that a major part and probably most of recent global warming is due to anthropogenic increass in greenhouse gases“.

    Still, there must be a plethora of consequences for that: the fact that my “monsoon challenge” remains unchallenged may indicate that we are indeed “missing a major (not necessarily feedback) process that would eliminate most of the effect of increasing CO2

    Look for example at the news that forests may be releasing much more methane than anticipated. Perhaps we are living in a world where the amount of atmospheric CO2 is irrelevant to climate change, in the presence of certain levels of other greenhouse gases (and ice-house atmospheric components)

    Coby (172): We are still back to square one about the methods of skepticism. A Skeptic does not need to come up with alternative scientific models and/or theories.

    The “job” of the skeptic (and everybody should be a skeptic at heart, at least in the scientific community) is to point out flaws in reasoning, absence of or poor evidence supporting a theory, and in general to challenge a theory or model by asking for its consequences to be clear for all to see.

    I may be wrong, but I don’t think Einstein was incensed by the fact that Relativity had to “pass” the 1919 eclipse test by Eddington, and quite a few more eclipse tests before really being accepted

  174. Pat Neuman:

    re 173 said – And we are talking .2F, surely that’s not enough to make flowers appear in January where 20 feet of snow was the norm?

    The part that’s significant is that for all ten year averages of annual temperatures 1820 – 2005, 186 years of record, the 1996-2005 average was the highest. Although only by 0.2 F, a 10 year moving average trend appearing as it does over the last 30 years, is unlikely to fluctuate of decrease. Instead, other observed changes in the worlds ice, warming oceans and soils, mean there will likely be an acceleration in the 10 year moving average warming trend, indefinitely, which also means doom to many species.

  175. Hank Roberts:

    > 173
    If you find the PETM event reassuring, I find that utterly astonishing.
    Excuse me, but that’s inadequate. It sounds like someone’s feeding you misinformation and you aren’t checking it. Where did you find this so-called reassurance?

    Wiping out the existing biota and leaving a wasteland in which new species can find opportunities did work for us mammals, assuming you are reassured by evolution.

    But it wiped much of the surface of the land off (“weathering”) and washed it into the ocean. That’s why there was such an opportunity. The old regime was washed away and ended up in the ocean sediments, where it was found in ocean drilling.

    Who are you quoting? I’d like to know where you get the reassurance.

    Here’s one description I recommend as a start. Note the warming in that event — it’s not a lot more than we’re looking at currently as possible.


    “In terms of the rate and degree of warming, the PETM is unprecedented in Earth history. Isotope records suggest that at 55 Ma the deep-sea and high-latitude oceans warmed by 4° and 8°C, respectively, in a period of <10 k.y. (Fig. F8). This period of extreme warmth, which lasted <150 k.y., triggered profound changes in global precipitation and continental weathering patterns (e.g., Gibson et al., 1993; Kaiho et al., 1996; Robert and Kennett, 1994). The PETM also affected biota on a global scale, triggering both rapid turnover of benthic and planktonic organisms in the ocean (Kelly et al., 1996; Thomas and Shackleton, 1996; Thomas and Ward, 1990) and a sudden radiation of mammals on land (Clyde and Gingerich, 1998; Koch et al., 1992; Rea et al., 1990).”

  176. Maurizio:

    Re: 175

    An “unprecedented warming in Earth history” ends up with species thriving in the new environment.

    If you don’t find that reassuring, I find that “utterly astonishing”.

    For me it’s just more evidence that whatever we humans will punch or pull on the environment, the natural world will simply adapt and thrive

    And that’s truly reassuring

  177. Coby:

    For me it’s just more evidence that whatever we humans will punch or pull on the environment, the natural world will simply adapt and thrive

    This is very true. Likewise, whatever toxic waste we dump into rivers and groundwater supplies, it will eventually dissipate, breakdown, dilute what have you. We can also make as big a pile of nuclear waste as we want and eventually it will be safe to walk on it again.

    But unless one is a true sociopath, how is it possible to think that that makes creating those messes ok, and the generations of people suffering through them, waiting until that blessed day comes when nature finally finishes cleaning up, just don’t even rate a second thought?

    This is an utterly self-serving position to take.

  178. Dano:

    Re 175:

    For me it’s just more evidence that whatever we humans will punch or pull on the environment, the natural world will simply adapt and thrive…And that’s truly reassuring

    Your conclusion is based on the premise that ‘thrive’ is true. And that’s truly not reassuring.

    At the very least you should name a time scale, as ‘good’ on a geologic time scale is far different than on a human societal time scale [scale is fundamental in ecology].

    (and re 173: your modifiers in were clear and unprecedented, thus my response. Note the difference in wording between bolded 157 and 173, a clue.)



  179. Dano:

    Coby and I have not collaborated in the making of our comments. But his point about scale is perspicacious and well done.


  180. Hank Roberts:

    Maybe we agree. I find this reassuring, on a geological time scale –and cautionary, on the human time scale:

    “…’What did you do about the dinosaurs?’ he demanded. ‘Did they annoy you? How did you fix them?’ …”

  181. Kenneth Blumenfeld:

    Someone said it before, and I’m too lazy to figure out who, since I just read the last 45 posts, but I don’t think Maurizio can be satisfied. Extraordinary evidence? “The Day After Tomorrow?” If you need Hollywood action to convince you, then I guess yes, you will definitely enjoy the coming decades.

    As for a not-so-extraordinary process: the conditions Pat described have been due to an increase in split jet streams over the upper midwest (among other synoptic/dynamic explanations). If indeed that is because of global warming, then there is one weather pattern for you. For excitement, Minnesota experienced its latest 100-year rainfall on record this year, after setting dewpoint and maximum low temperature records also. You would have had to go up to the rural St. Croix river valley to see the worst of it, but if you just imagined a city of 300,000 there instead, then maybe you can have some of the carnage you are after.

    (I know, you can’t pin a single event on global warming. But you can observe that late-and-early-season extreme rainfall events are happening more frequently. I do wonder what that’s all about.)

  182. Maurizio:

    Coby (177): It is the second time you try a straw-man argument on me. I don’t think we should mess about the planet “because it’ll be alright in the end”. And I never wrote anything of the sort. I am just glad that there is no indication that our actions can sterilise the planet

    Dano (178): Please don’t try to second-guess me, it’s a waste of time. It is true, I have not repeated “clear and unprecedented” in 173. I don’t see why I should necessarily have done so: a few lines above in 173 I asked Pat about extraordinary evidence, for the umpteenth time. If that’ll make you happier, let me rephrase my question to you: Is it really that much to ask for the ONE weather pattern that has changed clearly and without precedent due to “global warming”?

    Hank (180): haven’t read that story yet but thanks for understanding my point

    Kenneth (181): You haven’t read the messages. Here’s how I can be “satisfied” that there is a dangerous “global warming” going on at the moment: find me a weather pattern that has changed clearly and without precedent.

    Examples are: monsoons shifting (north, east, west, south, you decide); repeated rainfalls in dry deserts; jet streams disappearing from one area and/or appearing in another; sustained hurricane seasons in areas previously seldom touched, like the South Atlantic; january flowering in northern Siberia; year-long ice-free opening of the Northwest Passage, with little or minimal iceberg and sea-ice threat. Etc etc

    It’s really only a matter of imagination. My reference to Hollywood was simply that even the director and writers of TDAT understood that either something clear and unprecedented happens to the weather, or “global warming” will always remain a matter of debate and belief

    I am skeptical of global warming, but I am even MORE skeptical that global warming somehow would not be able to clearly CHANGE a single weather pattern

    I do have a problem with my skepticism, and that is that (as yet) I cannot find how to tell between human-induced and “natural” global warming. But as I wrote twice already, I am open to suggestions, as long as they go beyond the “it can’t be a coincidence”

    [Response: What you’re using here is argument from personal ignorance. Which is unconvincing. If you want a specific non-temperature attribution paper, then you can have Gillett et al, Detection Of Human Influence On Sea – Level Pressure. NATURE 422 (6929): 292-294 MAR 20 2003. If you’re interested in detection and attribution in general, then the IPCC report is probably the best place for a general info and refs to the literature: chapter 12 – William]

  183. Dano:

    Re 182:

    You did it again. Science is probabilistic. You seem to be asking for incontrovertable proof, and folk are responding to you like you are. Your phraseology is one that quibblers use to pooh-pooh away evidence. You see this tactic all the time, in public health, in agriculture, in AGW. Note: I’m not saying you are purposefully doing this.

    So, when I say in response you your ‘weather pattern’ question: earlier spring in US Northeast, quibblers say: blablabla not clear evidence yadayada. That’s the game, and why folks are replying to your posts in this way.

    There. Earlier springs/shorter winters in the US Northeast [1., 2., 3., 4., 5.].



  184. Hank Roberts:

    A Conversation with Kerry Emanuel
    With Findings on Storms, Centrist Recasts Warming Debate

    “I predicted years ago that if you warmed the tropical oceans by a degree Centigrade, you should see something on the order of a 5 percent increase in the wind speed during hurricanes. We’ve seen a larger increase, more like 10 percent, for an ocean temperature increase of only one-half degree Centigrade.

  185. Lloyd Flack:

    Re 173 Maurizio

    I’m slightly confused. Are you looking for unequivocal incontrovertible proof of the warming trend itself or proof of its being caused by human activity.

    You seem to be looking for a simple dramatic demonstration of the effect of global warming that you can use as a proof of its reality. I think the problem is that most climate scientists don’t see things such as you are looking for as proof of global warming trends at all. They see them as illustrations of the effects of global warming but dramatic events tend to be rare events and are not good evidence of trends. To connect, say cyclones in the South Atlantic, with global warming we need explanations connecting the two events. One might conceivably be able to come up with alternative explanations of the events that you are looking for. Yes I think that climate scientists can come up with dramatic changes that are a result of global warming. Attributing them to global warming is more difficult.

    The evidence for trends in global average temperatures comes from thousands of temperature measurements taken at many locations around the world. This is very noisy data and one has to do a lot of work to extract the signal from it. But now we have very strong evidence of increasing trends in surface temperatures, in Tropospheric temperatures and in ocean temperatures. These are incontrovertible proof of global warming. They are the best available kind of proof since they are direct measurements of the temperature itself. Unfortunately they aren’t simple or dramatic or easy to interpret. This is the nature of the beast. They are measurements of trends where there is great natural variability both from region to region or from year to year. But they are actually better proof of global warming than the things that you are asking for.

    If you are looking for proof that anthropogenic increases in atmospheric CO2 have driven global warming then the incontrovertible proof that you want is not possible. This is because we cannot do experiments. We only have data from observations on conditions that we cannot control. All we can do is create the simplest explanations that we can which are compatible with what we know of the physical processes involved and with the observed data. We then make predictions from these models and look for observations that can be used to test these predictions. The current models while hardly simple are compatible with the physics and the observations and take account of all the likely forcing variables. There is no need to introduce unknown processes to explain the observations. Greenhouse skeptics now have to come up with detailed alternative models to be credible. No such models have been created.

    The temperature record was not unequivocal until August last year with the reinterpretation of the Tropospheric temperature data. I did not have a lot of confidence in the climate models until they took natural forcing variables such as Solar variation and volcanism into account.

    Unfortunately global warming is a messy problem. The proofs of global warming are similarly messy. I have to agree with Dano (161) on this one.

  186. Maurizio:

    William (183): Thank you for those links. I don’t think a question like “How can I distinguish human-made from natural global warming” is really a way to argue using one’s “ignorance”

    Dano (182): I am sorry that you don’t want to read my messages in full. Far from pooh-poohing any evidence, I have even written that “I could get along with the statement that the preponderance of evidence is that a major part and probably most of recent global warming is due to anthropogenic increass in greenhouse gases“.

    If you and all others agree that there is NO incontrovertible evidence (as yet) for Human-made Global Warming, well, what’s wrong with me saying “I am all for free speech and free thinking, so go ahead, and campaign to sequestrate CO2 and reduce the use of coal as fuel. But please don’t dress it up (yet) as ‘hard science’” ???

  187. Dano:

    Re 186:

    If you and all others agree that there is NO incontrovertible evidence (as yet) for Human-made Global Warming, well, what’s wrong with me saying…

    If you want to believe that hard science – which is probabilistic – can make your world incontrovertable, then there’s nothing I can do for you. Sadly, I am unable to reduce my argument to monosyllaby as an aid to clarity and understanding – I simply lack those skills. You may want to read Lloyd’s 4th para in 185 a few times, as it succinctly bounds the issue. William, though, hits upon the ‘economy of phrase’ prize in the first sentence of his response to you in 182; it is the heart of the matter and the reason why I will now wish you well, Maurizio, in your quest for knowledge.



  188. Coby:

    Maurizio, I think you would be hard pressed to find any scientist who would say that there is incontrovertible evidence for Antropogenic Global Warming. But the fact that you are still stuck on this only means you have not yet understood that there can never be incontrovertible evidence. If statistical correlations, sophisticated models and internally consistent theories that explain all of the available evidence is not enough for you, then you will, by your own choice of metrics, you will never be convinced. It does not matter how hot it gets, or how many weather patterns change, the proof you seem to ask for does not and can not exist in earth sciences.

    Thus, a person holding out for such proof is not a sceptic in any respectable sense, this is just denialism.

    I asked you before what was special about monsoons and the sahara dessert such that a change there is incontrovertible yet the rapid retreat of glaciers world-wide is not, and I do not recall seeing you address this. The sahara has not always been a dessert, so if it is one day again not a dessert, how will you know that is the result of AGW?

    I know you took exception to this comment before, though I am not satisfied you were right to, but I repeat: faced with the dangers that the best science warns of, based on very voluminous and consistent evidence, it is utterly unacceptable to say “prove it” and tacitly or explicitly endorse a “damn the torpedos, full speed ahead” social policy.

    That’s one hell of a gamble with something unique, priceless and not ours to damage.

  189. joel Hammer:

    I notice that people have “moved on” or away from the great human induced drought in the Sahel.

    This simply proves my point. If something is inconvenient, in this climate debate people just ignore it. Going back to my favorite professor, a great quote from him was:
    “Facts are always friendly.”
    Not in this debate.

    A quote from Mark Twain:

    There is something fascinating about science.
    One gets such wholesale returns of conjecture
    out of such a trifling investment of fact.

    And to think, he noticed this before the advent of computer models.

  190. Hank Roberts:

    Joel, in your Sahel posting, for me, the latter two links required a login, that you didn’t provide; the first led only to an abstract — membership needed to read the actual article. Hard to comment given only that much.

    Did you mean to illustrate aspects of skepticism? You didn’t say what you thought the links stood for.

    I’m skeptical (wry grin) that people’s lack of response to your Sahel posting in this thread supports your conclusion that people won’t discuss “inconvenient facts” about climate.

    The Sahel drought’s been discussed for decades. I recall it being discussed in geology classes I took back before continental drift was accepted — that was in the late 1960s. Explanations have changed quite a few times since then!

  191. Maurizio:

    Coby (188): You still seem to think I am on mission to turn the planet into wasteland. I am not.

    This thread is about “how to be skeptical”.

    I have simply explained why and how I can be skeptical within a scientific framework.

    Ironically, it’s now you saying there is “no incontrovertible evidence” for Human-induced Global Warming: I’d just content myself with the list posted @ 182

    Going back to what’s special with a shifting monsoon, etc, it’s that for the FIRST TIME we would witness a CHANGE in a weather pattern THAT IS NOT JUST a change in intensity (a change in intensity being ipso facto hard to de-couple from a freak phenomenon or some long temporal cycle)

    Perhaps there is scientific literature about why no weather patter has been changing so far. Or perhaps there are peer-reviewed articles about which weather patterns have been changing already.

    My esteemed colleagues of thread are very welcome to point me in the right direction!

    Can we all agree that if global warming continues as predicted, there WILL be changes to weather patterns?

    And by the way: if you want an example of scientifically incontrovertible proof, read about Einstein’s theories and Eddington’s (and later) observations of shifted star positions during solar eclypse

    After all, in brain science people publish scientific articles after scanning a handful of people, but in social science nobody can pass the reviewers without a robust sampling of the general population

    And therein may lie the difference between what is, and what is not (as yet) “hard science”

  192. Maurizio:

    Lloyd (185): Somehow we agree on the reasoning, but not on the conclusion.

    For me it’s a matter of “messy data” getting demonstrated by something you define “dramatic”. I agree that the reconciliation of the Tropospheric temperature measurement sets is “a step in the right direction”. For you it was enough…my jury is still out!

    (thank you Dano for pointing me to that comment, I had missed it earlier)

  193. Dano:

    RE 189:

    joel, perhaps your argument lacks cogency.

    For example: what are you inferring? Your words are arranged and expressed such that it appears you want to say because someone was wrong once everyone is always wrong. That is what I get from your words, and why I ignored your comment. Perhaps you can restate your argument for clarity.

    Perhaps you wish to say that tree rings as proxy data are not OK as evidence, even as used in a paper way back in 1978, presumably before CO2 fert issues in the record. Perhaps you wish to state the NVDI record is too short to use for evidence, hence more study is needed. Or perhaps you are pointing out that human activities on marginal lands lead to desertification, which exacerbates natural cycles. Or that CO2 doesn’t cause desertification [and this, somehow, relates to some other unstated assertion].

    You may be saying all of the above, or none, or some. No one knows. You want to dismiss this comment thread as ignoring “inconvenient facts” when in all likelihood your “facts” weren’t compelling due to lack of clarity. Here is an opportunity to clarify them to assuage your concerns.



  194. Pat Neuman:

    re 191 … “Can we all agree that if global warming continues as predicted, there WILL be changes to weather patterns?” …

    Weather patterns have already changed.
    See figures and tables at:

  195. Maurizio:

    Pat (191): Most of your links are way too generic to be used. And nobody will seriously argue that a change in snow melting in one area can be considered an incontrovertible proof of anything?

  196. Lloyd Flack:

    re 192

    Showing that there has been a temperature trend and proving that it is due to human activity are separate problems.

    The reconciliation of the Tropospheric temperature data was the final proof that the temperature is increasing. It says nothing about the cause of the increase.

    The best evidence of a temperature increase is the temperature measurements, not climate pattern changes which are consequences of the temperature increase. True one has to do a lot of work to combine them into meaningful global averages. I’m quite happy with proofs which depend on lots of pieces of data none of which are conclusive by themselves but which it strains credibility to disbelieve in total. Hey, I’m a statistician. It’s what I do.

    If you want the qualitative changes in weather patterns then other commenters on this blog would know better than me what they might be. But they are not proof of temperature trends. The measurements are.

    Where I believe you cannot have inconrovertible proof is in the attribution of temperature trends to human activity. Or rather the attribiution of a major part of the trend. The physics of the situation tells us that increasing greenhouse gases will raise global temperatures. The question is how much.

  197. Hank Roberts:

  198. Pat Neuman:

    In 191. Maurizio wrote: “Can we all agree that if global warming continues as predicted, there WILL be changes to weather patterns?” …

    In 194. I replied that … Weather patterns have already changed.
    See figures and tables at: …

    In 195. Maurizio wrote: “Most of your links are way too generic to be used. And nobody will seriously argue that a change in snow melting in one area can be considered an incontrovertible proof of anything”?

    A change in the timing of snowmelt by 4-5 weeks earlier, as shown by a 10 year moving average trend on streamflow runoff, means there has already been “a change in weather patterns”. Winters are warmer recently than decades ago. The polar jet rarely makes an appearance anymore. When the Arctic air does arrive, it’s not as severe or long lasting as years ago (based on 186 years of record at Minneapolis, 100 years of streamflow runoff, and 110 years of temperature measurements at NOAA NWS climate stations in eight Upper Midwest states (sd nd mn wi mi ia il in).

    Links at 194.

  199. Dano:

    110 years of temperature measurements at NOAA NWS climate stations in eight Upper Midwest states…

    More ice-free days on the Great Lakes [leading to lower levels due to increased evap.], earlier snowmelt and later ice-up in the NE…



  200. Jo Calder:

    Re 197:

  201. Hank Roberts:

    > 197, 200:

    ” … global warming can lead to lots of strange local climate change. At several research stations in the study, scientists have found that the maximum daytime temperature has actually gone down. At night, on the other hand, the minimum temperature has been going up. Clouds may be causing this pattern ….. as nights get warmer, the mid-elevation forests are becoming the perfect breeding ground for the fungus. And harlequin frogs there have paid the price.

    …. pseudo-skeptics try to claim that we can’t learn anything about extinctions or how they might be accelerated by future climate change …. The equation is far from simple. … as far as I know, no one predicted that it would be nighttime warming and daytime cooling that would make the fungus so deadly. …. “

  202. Barton Paul Levenson:

    Re Maurizio’s whole thread — it seems to me like he’s been handed EXACTLY the evidence he asked for, and dismissed all of it. I’ve run into this type repeatedly on AOL message boards and in chat rooms. Arguing with this guy is pointless. There’s nothing you can say that will convince him. It’s very much like beating your head against a wall, and our best response to it would be “it feels so good when I stop.”

  203. Pat Neuman:

    High humidity decreases rates of temperature decline overnight and rates of temperature rise in the day. The dust bowl of the Great Plains (early 1930s) had low humidity and high daytime temperatures (above 100 F).

  204. Maurizio:

    Barton Paul (202): I have even provided a list of what would convince me. Can’t imagine how I can be more honest than that

  205. Maurizio:

    About the trouble of working just with “trends”: look at the USGS earthquake statistics at

    Here’s the total number of quakes from 1990 to 2005

    1990 16590
    1991 16484
    1992 19524
    1993 21476
    1994 19371
    1995 21007
    1996 19938
    1997 19872
    1998 21688
    1999 20832
    2000 22256
    2001 23534
    2002 27454
    2003 31419
    2004 31194
    2005 29867

    There is a clear upward trend that would make any IPCC committee salivate twice over…is there perhaps an upcoming Nature paper linking earthquake activity and man-made greenhouse gases???

  206. Maurizio:

    Dano, Coby and Lloyd (several comments): How should I reconcile your statements about there being no incontrovertible proof for global warming of the dramatic kind I have been waiting for, with the gloomy forecasts recently published by James Lovelock (not to mention the End-of-the-World-is-Nigh from one of the recent Fortune magazines)?

    If “Before this century is over, billions of us will die” (Dr. Lovelock’s text, not mine), is that going to happen all of a sudden, will it all be a matter of weather extremes (remarkably, without a single weather pattern moving anywhere) or will we be graced with a few “incontrovertible proofs” that global warming is indeed going to kill us all?

    Methinks there is a lot in common with all these disaster articles, and the dire predictions years ago about the impending population disasters that never were

  207. Hank Roberts:

    > earthquakes
    Bogus. Careless or wilful misrepresentation, see footnote on linked page.

    > As more and more seismographs are installed in the world,
    > more earthquakes can be and have been located. However,
    > the number of large earthquakes (magnitude 6.0 and greater)
    > have stayed relatively constant.

  208. Coby:

    Dano, Coby and Lloyd (several comments): How should I reconcile your statements about there being no incontrovertible proof for global warming of the dramatic kind I have been waiting for, with the gloomy forecasts recently published by James Lovelock (not to mention the End-of-the-World-is-Nigh from one of the recent Fortune magazines)?

    I think, Maurizio, you are falling into a very common trap, so I will not be too harsh on the lack of logic in the question you ask above. The trap is to view this issues as “us versus them”, two poles, chose your side etc. This is shallow to the point of being doomed to fail in providing any insight whatsoever. I don’t think you mean it.

    But here’s the answer:

    First, what is there to reconcile? I am not James Lovelock, he is not me. He has his own opinions, anyone who makes the minimal effort to understand this issue will have their own.

    Second, he is telling you what he thinks will happen, I don’t think you will catch him ever saying or thinking that their is incontrovertible proof it will be so.

    Third, he is talking about what the future holds, not what we are reading in the newspapers of journals today, which is where you are looking.

    Because of the nonsensical nature of your question, I think you are just being inflammatory. You are also now exhibiting all the hallmarks af a septic, not a skeptic, making obvious errors in logic, unsupportable assumptions about what others believe etc, not to mention the mocking tone you adopted in comment #205. We can do better than that, even in the face of disagreement.

    As for incontravertible proof, it is true you presented a list of what you would accept. But you did not at all address my questions to you about why those things are proof but everything else we see happening isn’t.

    I’ll be frank with you, I don’t believe you that any of those things would be any more convincing to you. As I said before, the Sahara was not always a desert, if it turns green now how will you prove that is due to global warming? What do you know about the history of monsoons before the emergence of record keeping in asia? They may not have always been there.

    If you ask me, the day these drastic changes do come will be far too late to do anything about it. And there will still be people denying that it was our fault.

    You have never been very clear about what it is you want proof for. Are you sceptical that the temperature is rising? Changing weather is hardly needed to prove that, just look at the temperature records. Do you need proof that it is because of anthropogenic influence? I repeat what I said above (and you never addressed) there is quite simply no proof possible. There can only ever be statistical correlations, sophisticated model output and internally consistent theories that explain all of the available evidence. You need multiple planets to run experiments on for anything better. Are you sceptical that a rise in temperature will be bad? That is the only place where intelligent scepticism still has an excuse, though again the balance of evidence says we need to worry about it.

    I worry when discussing with people who do not make it clear what they do except and what they still doubt. Maybe if you cleared that up some useful discussion could still ensue.

  209. Pat Neuman:

    re 205 Maurizio wrote … About the trouble of working just with “trends”…

    Trends by themselves are insufficient. Understanding the trends is required.

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