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My footnote about global warming

At the beginning of my article, How to think scientifically about scientists’ proposals for fixing science, which we discussed yesterday, I wrote:

Science is in crisis. Any doubt about this status has surely been been dispelled by the loud assurances to the contrary by various authority figures who are deeply invested in the current system . . . When leaders go to that much trouble to insist there is no problem, it’s only natural for outsiders to worry.

And at that point came a footnote, which I want to share with you here:

At this point a savvy critic might point to global-warming denialism and HIV/AIDS denialism as examples where the scientific consensus is to be trusted and where the dissidents are the crazies and the hacks. Without commenting on the specifics of these fields, I will just point out that the research leaders in those areas are not declaring a lack of crisis—far from it!—nor are they shilling for their “patterns of discovery.” Rather, the leaders in these fields have been raising the alarm for decades and have been actively pointing out inconsistencies in their theories and gaps in their understanding. Thus, I do not think that my recommendation to watch out when the experts tell you to calm down, implies blanket support for dissidents in all areas of science. One’s attitude toward dissidents should depend a bit on the openness to inquiry of the establishments from which they are dissenting.

72 Comments

  1. a reader says:

    I’m definitely not a AIDS or climate denier…but I’m not sure your logic holds. In particular, the leaders in those fields (sadly) are loudly declaring a lack of a crisis *in their methods*…but mainly because they are being required to discuss such counter evidence as “well I just got this snowball from outside, so I think its safe to conclude that global warming is a hoax”.

    Statistic’s closest equivalent is loudly claiming that machine learning methods don’t work. I don’t think one size fits all, but there’s a surprising amount of statisticians who appear in denial about just how many problems fit that one size.

  2. RbTM says:

    ==> “One’s attitude toward dissidents should depend a bit on the openness to inquiry of the establishments from which they are dissenting.”

    ____

    … well, a rather vague statement — intentionally so IMO.
    Seems a belated and oblique recognition of the outrageous large-scale suppression of legitimate scientific objections to AGW Theory (especially) by governments, academia, and establishment media, over several decades.

    why should your subjective “attitude” toward the person of a dissenter… at all influence the objective accuracy/truth of the specific dissent presented ?

    …and just how does one gauge “the openness to inquiry of the establishments” ?

    Consensus has no place in science as a benchmark of truth. Majority Rule is not science.

  3. Carlos Ungil says:

    Maybe their “openness to inquiry” has improved in the last years, but the global-warming establishment has produced gems like

    “We have 25 or so years invested in the work. Why should I make the data available to you, when your aim is to try and find something wrong with it.”

    and

    “If they ever hear there is a Freedom of Information Act now in the UK, I think I’ll delete the file rather than send to anyone…”

    • Adede says:

      Those sound like exasperated reactions to many bad-faith requests for “dialogue”.

      • Phil says:

        Yeah, it’s worth noting that that quote, although accurate, is misleading. The scientist who was being asked for the data did not have permission to distribute them; he pointed his correspondent to the source of the original data; he pointed out that gridded (as opposed to raw, location -coded data) were available on a particular website; and he even followed up to try to help his correspondent engage with the organization that did have the data. It’s true that he said that even if he did have permission to share the data he wouldn’t send them to his correspondent — and then he gave the quote above — but given the context this was clearly not an attempt to suppress the raw data, he was just being petty about not wanting to make things easy for his correspondent. It’s bad, but it’s not _that_ bad.

        To be fair, the way many of the global warming “skeptics” have behaved would frustrate any scientist. Still, one should always share data when one has permission to do so.

  4. Peter Dorman says:

    A lot of energy is being put into coming up with a set of criteria that allows us to distinguish between “virtuous”—honest, truth-seeking—skepticism toward science and dishonest or at best ignorant attacks like climate denial. Most of us probably agree the mainstream political position, that 97% of climate researchers agree that anthropogenic climate change is a problem, is not a good road to go down, since it is sometimes true that scientific fields will congeal around a consensus that is vulnerable to criticism. That has happened noticeably in my own field of economics (which may or may not be a science).

    So I see you trying out another approach: a skeptical posture is warranted only if the grandees of a given field have behaved in less than open, criticism-seeking manner. Skepticism functions as a countervailing force, justified by the shortcomings it tries to expose. I see the value in this: the less open I am to critique the less you should trust me. I don’t think it’s the whole story, however, since it’s possible for a disingenuous line of criticism to be launched against a somewhat close-minded community of practitioners, just as it’s also possible for a self-critical community to be vulnerable on account of having collectively overlooked something important.

    I would rather try to distinguish honest from dishonest skepticism, always welcoming the first and rejecting the second, no matter the virtues and sins of the field being critiqued. An honest skepticism is based on more than a generic call to doubt; it needs to have reasons. What makes climate science relatively invulnerable to casual criticisms by outsiders is that, since it draws on largely corroborative evidence from a wide range of data sources and techniques, plausible counterarguments have to be pretty sophisticated. Anyone who has more than a passing familiarity with the literature knows you can’t just point to possible measurement error in a single study and claim the whole field has been called into question. It also helps that, as Arrhenius figured out, the theoretical premises of chemistry and physics virtually require that widespread fossil fuel burning should have this effect; to disbelieve you would need a powerful argument why the current situation constitutes an exception.

    To me it is this cumulative character of the research literature and not percentages of agreement among practitioners that justifies the term climate “denial” rather than “skepticism”: the arguments of the Heartland Institute et al. are not serious. To go back to the search for a general rule, to me there is no avoiding the need to assess the quality of argument—the bar that has to be cleared in a given field for outsiders to pose meaningful criticism of it and the extent this bar is cleared, or even trying to be cleared, by critics.

  5. Peter says:

    My (limited) experience with climate researchers has not been consistent with your footnote. Climate change researchers have tried incredibly hard to avoid data-sharing and consciously try to sweep dissent under the rug. The scientific standards in the subfield are embarrassing. I’m speaking as a far leftist who strongly believes in anthropogenic climate change. There’s an important distinction to be made between (1) being right about the facts and (2) being sound in your methods. Being right and doing good science are orthogonal.

    • Phil says:

      Peter, can you give some examples? I hope there’s something more than “but the Hockey Stick, although pretty much accurate, wasn’t calculated correctly. And Phil Jones said 14 years ago that he wouldn’t have shared someone else’s data even if he had permission to do so.”

      It’s not my field but from online searches I have found lots of data to be readily available. For example https://www.nodc.noaa.gov/OC5/WOD/pr_wod.html and https://www.nodc.noaa.gov/General/sealevel.html and https://www.ncdc.noaa.gov/cdo-web/datasets

      No doubt there are some bad researchers in any field (in all the ways a researcher can be bad) but I do not think climate science has a special problem.

      • I think Climate Science has a special political problem, and this political problem damages its actual scientific action. Any normal level of scientific skepticism, like saying “We really don’t have a good idea of the proper size of coefficient q, it could easily be anywhere from 1e-3 to 30” would be seen as politically extremely vulnerable, and so that kind of normal scientific discussion doesn’t happen anymore in public.

        So, anyway, there are other areas where similar things occur, like Economic policy models or environmental impact assessment of pipelines or solar arrays or plastic in the oceans… anyway politics is usually not helping science be more sciencey

      • Terry says:

        Are you at all concerned about Michael Mann’s research and behavior?

        • Phil says:

          Terry, it was certainly wrong for Mann to distribute unpublished manuscripts without the knowledge and consent of their authors, but I consider that to be a venial sin…actually among the most minor of venial sins.

          It’s hard for me to believe that’s the behavior you are asking about, but what else is there? The ‘hockey stick’ calculation was wrong but gave the right answer. I’ve made errors myself that I have failed to catch because my model fit the data so I assumed it was behaving correctly, so I’m hardly one to throw stones there. I am not concerned that a scientist makes a mistake every now and then.

          Checking Mann’s Wikipedia page, I am reminded of the ‘climategate’ controversy. I’m tempted to draw a parallel with ‘but her emails!’ but it doesn’t really work here because Hillary Clinton really did do something wrong, but Mann did not. It’s more like “Benghazi! Benghazi!”: wild claims from partisans, investigated in depth, with allegations found to be false.

          In short, based on what I’ve seen about Mann, I am not concerned about his research and behavior and I find the question a bit odd. Should I be concerned? What do you know that I’m not seeing, Terry?

          • Terry says:

            My intent was not to argue.

            My intent was just calibration. You seem very knowledgeable, and I have found your posts very informative, but I have little ability to check them. Mann and the hockey stick is the only area of climate science I have read about in depth and have some ability to have an informed opinion on. I wanted to use that as a benchmark to evaluate your other posts.

            FWIW, this video by Dr. Muller is a rough approximation of the opinion I have formed. https://www.youtube.com/watch?v=8BQpciw8suk. Note that this does not mean that warming is not real, a point which Muller makes in other videos. I don’t consider this a sport where the focus is on who ultimately wins. Rather, my interest is the more general topic of how much we can trust academic research.

            Again, my intention is not to argue. Honestly. I’m just trying to work things through in my own mind.

            • Phil says:

              Terry,
              Like you, I only know what I read in the papers. I saw a bunch of stuff about ‘Climategate’ and the hockey stick and all that. I paid some attention, I read what had happened with the hockey stick, and when there were formal inquiries into Climategate I read the reports. This was all quite a while ago now and I had forgotten about ‘climategate’ altogether until I read the Wikipedia article. Basically I saw a few mistakes and bad choices, but mistakes and bad choices get made in research all the time and I didn’t see anything that really bothered me. Still don’t. But there may be stuff under the carpet that I have never seen or heard about.

              Muller…I only watched a minute or so of the video you posted, but I did see Muller speak at Lawrence Berkeley National Laboratory (where I worked at the time) some years ago. Ah, here’s a comment I wrote about it (responding to a post about Charlie Sheen): http://statmodeling.stat.columbia.edu/2011/04/11/the_difference_7/#comment-58699
              It looks like your video is from before I saw him speak. I think Muller saw some mistakes and poor judgment by Mann et al and was convinced that these weren’t mistakes, they were deliberate attempts to exaggerate global warming. At the time he made the video you referred to, Muller had gotten funding (much of it from the Koch brothers, by the way) to do his own analysis. I’m sure the Kochs expectected (and I think Muller expected) that he would find that global warming had been exaggerated or fabricated. To Muller’s credit, he did the analysis (or, rather, hired grad students and postdocs to do the analysis under his direction) and, when he found the same results the Mann et al had gotten, he said so. To his discredit, he didn’t change his schtick at all: in the talk I saw, he talked about how these other climate scientists had done all these terrible things to exaggerate global warming…but then he said he had done his own _proper_ analysis and gotten the same answer they did. Uh, OK, doesn’t that mean the other climate scientists were NOT exaggerating global warming? Or does he think they were trying to exaggerate it, but failing? The fact that the other climate scientists, whatever their flaws, had gotten the right answer didn’t seem to make any impression on him at all.
              (Ah, a search turned up some additional discussion, this time on a climate-related post on this blog: http://statmodeling.stat.columbia.edu/2011/10/31/skepticism-about-global-warming-skepticism-skepticism/ )

              My conclusion is that most people in the business, or at least most people in these ‘controversies’, are trying their best to get the right answer. Some of them make mistakes, and some of them probably do make choices (via ‘garden of forking paths’ or p-hacking or even just plain fraud) that lead to wrong answers: that’s true in other fields and I don’t see why climate science should be immune. But on the whole I don’t think the field of climate science has a problem with systematic fraudulent behavior.

              • Terry says:

                Thanks for the thoughtful response.

                I watched the debate unfold from about 2000-2012. I was not impressed by Mann’s conduct.

                Mann’s “hockey stick” isn’t about measuring global warming in the recent past, so I don’t think it is correct to say that he got the same result. Mann’s work was primarily about estimating past temperatures using temperature proxies (i.e., before thermometer data is available) to see if the current upswing is unusual by historical standards. The hockey stick’s claim to fame is its estimate of flat temperatures before the 20th century so that current temperatures are the hottest in the past few thousand years. Prior to 2000, the consensus was that temperatures fluctuated substantially due to natural factors and that temperatures were high a few hundred years ago and high again back in Roman times (IIRC).

                Muller has focused on the temperature record which had also been called into question. But that is a different issue. As you note, his results are similar to the previous results.

              • Phil says:

                Terry,
                You probably followed the Hockey Stick and Climategate stuff more closely than I did at the time. With regard to the Hockey Stick in particular, the main message I got is that the statistical method used was wrong — beyond the ‘all models are wrong, some models are useful’ kind of wrong — but that for this particular dataset it didn’t matter, you get the same answer when you do it right. That is very clear evidence of an innocent mistake: if you know you can get the answer you ‘want’ by using the correct method, you would never do it wrong. So, OK, Mann et al. made an innocent mistake in their analysis, but fortunately it didn’t affect the result. Indeed, if the mistake had been such that the model fit the data very poorly they would have caught the mistake, so perhaps it’s inevitable that it didn’t affect the result very much.
                So, innocent mistake in the model used, but one that hardly changes the answers…the fact that this became a ‘controversy’ seems ridiculous to me. The ‘skeptic’ community was all over it as proof of…well, of what, exactly? Somehow they, or at least some of them, tried to turn this into evidence that Mann was cooking the books. I didn’t get it then and I don’t get it now.
                I don’t have much to say about how Mann handled it; as I said, you probably followed it more closely than I did. I certainly was disgusted by the behavior of some of the people who went after him.

  6. Matt Skaggs says:

    Peter Dorman wrote:

    “there is no avoiding the need to assess the quality of argument”

    I spent my career doing exactly this on causation arguments. Intrigued by global warming, I spent considerable time on climate science, which is much more accessible to outsiders than the experts want you to believe (the stats are the most confusing part for me!). When I got everything mapped out using cause trees, the conclusion I came to is that the theory of anthropogenic global warming is structurally very weak. It is based almost entirely on unvalidated models, with no real hope for input/output experiments (known here as “treatments” I think). There are no direct measurements of the most basic aspect of the theory, which is that the CO2 pause is moving outward. There are multiple nonlinearities and feedbacks that remain poorly understood. There is a very weak historical record – and not even a real clear concept -of what “normal” looks like. The list goes on.

    So I will just tell you, because I am now amply qualified to say it, that the “cumulative character of the research literature” does NOT support calling global warming skeptics “deniers.” Which is not the same thing as saying that there is no dishonest skepticism on this topic.

    The grandees of climate science tolerate no dissent. The IPCC was formed specifically to steamroll over dissent! Andrew wrote that “…[climate scientists] have been actively pointing out inconsistencies in their theories and gaps in their understanding.” You can find examples of that from 10+ years ago, but nothing like that from the IPCC since. So I guess the point of this rant is that global warming actually does fit neatly into Andrew’s model of stated confidence being inversely related to the strength of the argument.

    • Chris Wilson says:

      Go back and study Arrhenius some more. The basic science underlying anthropogenic warming is well known, old and has a robust basis in physical science. I’m sorry you must have wasted so much time with those causal trees!

      • Terry says:

        Do you recall the 1930s paper that projected future temperature increases for a given CO2 increase?

        • Chris Wilson says:

          Arrhenius published “On the Influence of Carbonic Acid in the Air Upon the Temperature of the Ground” in 1896! In that paper, he estimated a 5-6C warming from a doubling of CO2. After more refinements, and a better understanding of relevant feedbacks, the estimated range has been 1.5-4.5 since the 1970’s. So Arrhenius was high, but the basic point – the physics of greenhouse gases reliably predict increase global average temperatures with increased GHG concentrations – is not up for debate, and the approximate range has been known for around 100 years.

    • Phil says:

      Matt,
      You’re right that there are multiple nonlinearities and feedbacks that remain poorly understood. Everything else you say about the theory of anthropogenic global warming is, I think, false. For instance, you say the theory is based ‘almost entirely on unvalidated models.’ The earth-atmosphere system is complicated but some aspects of it lend themselves to relatively simple predictions that are subject to experimental test. Here’s an example: https://www.csmonitor.com/Environment/Bright-Green/2009/1110/why-is-earths-upper-atmosphere-cooling
      There are many more.

    • Peter Dorman says:

      We are off on a tangent, but it’s important to not let it go.

      “climate science, which is much more accessible to outsiders than the experts want you to believe”

      I don’t know what experts are being referred to; can you provide citations? Speaking for myself, I have been able to read and generally understand most of the primary literature I’ve taken the time to work through, and I’m an outsider (an economist), so I can vouch for the accessibility of this field. But I also never felt like anyone was trying to discourage me, either explicitly or by use of exclusionary jargon or methods.

      “cause trees”

      You mean causal trees, yes? I understand the value of this approach in engineering situations with a hierarchy of nested systems, but do the global carbon cycle and climate system yield themselves to this type of piecewise analysis? Or are you just applying the method you’d use to explain a plane crash on climate impacts because that’s what you’re familiar with? (Do you understand the difference between the design of a plane, with its distinct subsystems with separable effects, and the mutual feedback structure of climate systems?) (I once had a long, fascinating conversation with a Boeing fault engineer about whether and how subsystem fault models could be interactive. He thought yes, but his organization said no.)

      “the theory of anthropogenic global warming is structurally very weak”

      What does “structurally” mean here? It comes across as a handwaving term; if you mean something more precise than “I don’t like it” you should say what the structural flaw is. And what do you mean by “theory”? The chemistry of the greenhouse effect? The biogeochemical carbon balance? What part of the theoretical framework are you doubting?

      “based almost entirely on unvalidated models”

      By “validated” do you mean corroborated? Or something else? What else? If you look through the latest pub on global carbon balances, for instance, you’ll see a fair amount of cross-validation exercises. There’s also a lot of uncertainty, but within a range we should be very concerned about. (See https://www.earth-syst-sci-data.net/10/2141/2018/)

      “no real hope for input/output experiments”

      This is bizarre. Climate change is a planetary phenomenon and we have only one planet, so sorry, no control. It’s all one big treatment. Are you saying there is no basis for scientific knowledge without classical experiments? Incidentally, there are immense experimental literatures on components of climate science. Think of all the people doing test plots to determine the impact of CO2 enrichment on plant growth under different environmental constraints.

      “There are no direct measurements of the most basic aspect of the theory, which is that the CO2 pause is moving outward”

      Why do I feel I’m debating with a bot?

      “There are multiple nonlinearities and feedbacks that remain poorly understood.”

      Yes. This is one reason why climate models produce a significant range of results. You shouldn’t take any specific model as gospel; it’s the ensemble, which explore different assumptions, that matters.

      “There is a very weak historical record”

      Paleoclimatology has made giant strides in the past couple decades or so. I am blown away by the care and imagination that have gone into proxy measurements of the Paleocene-Eocene Thermal Maximum, to take one example—the example I highlight in my book. It’s such a brief period by geological standards, and you’d think backcasting was a hopeless dream, but people have found a variety of proxies for atmospheric carbon concentrations and terrestrial temperature anomalies, and there’s a broad overlap across them. Of course, the corroborative evidence for more recent periods, like the succession of ice ages and interglacials, is much more robust.

      “The IPCC was formed specifically to steamroll over dissent!”

      Did you find that in the founding documents? Reports from the relevant meetings of UNEP and WMO? It would be interesting to read where the key individuals said this.

      My general take is that climate scientists, with a few exceptions, have been reluctant to express the full range of their results, truncating the more alarming possibilities in order to avoid being accused of going beyond what they can say with confidence. We’ve seen that in the IPCC decision, now reversed if I understand correctly, to base projections of sea-level rise solely on thermal expansion and not speculate on possible loss of terrestrial ice mass. I think that’s unfortunate. At the same time, the specialist research literature, the stuff you find in the journals, is honest about gaps and inconsistencies. Back to the PETM, for instance, there is a vigorous debate over the role of marine methane releases in amplifying whatever initial trigger set it off. (Quite possibly an increase in vulcanism associated with the separation of plates in the North Atlantic.) This has important implications for the current situation, and researchers have scoured available proxy evidence to resolve it, even debating the chemical stability of marine methane. It’s quite fascinating for those who delve.

      I realize this is a long digression to dispute a diatribe with little prima facie credibility, but we all have to do our part. The audience for this blog is not just those who follow it but all the people who might stumble on it doing a Google keyword search or through aggregators or whatever.

      • gdanning says:

        +1 for the last paragraph, particularly “we all have to do our part.” That is a big reason that I still use Facebook – we all have a responsibility to push back, in a clear and reasonable way (as in Peter’s post) against dubious claims, be they about global warming, or economics, or politics, or what have you (and, of course, whether they be from the left or the right).

      • Radford Neal says:

        > > There are no direct measurements of the most basic aspect of the theory, which is
        > > that the CO2 pause is moving outward”
        >
        > Why do I feel I’m debating with a bot?

        You feel that way because you’re not reading carefully. Exhibiting bot-like behaviour
        yourself, you apparently associated “pause” with claims of a recent pause in global
        warming, and then associated such claims with “deniers”, who you seem to think are “bots”.
        Every link in this chain is dubious, but it actually goes astray at the very beginning.

        Read the sentence again. Does it make sense if “pause” refers to a pause in global
        warming? No. It only makes susense if “pause” is used in the sense of “tropopause”
        or “heliopause”. It must be a reference to the height at which the atmosphere
        ceases to be opaque to infrared radiation due to gasses such as CO2.

        It is indeed an absolutely central claim of the global warming theory that this height
        increases when more CO2 is added to the atmosphere. The only reason to expect higher
        surface temperatures is that they would be needed to produce the same temperature as
        before at this “pause”, as necessary for energy balance, when this “pause” is now higher
        (since temperature goes down with height).

        • Peter Dorman says:

          If the comment had referred to tropopause rather than “CO2 pause” it would have been clearer. I haven’t looked into troposphere heating, but I would be surprised if it hadn’t occurred. How responsive the tropopause height should be (at various locations) to this trend is outside my knowledge: what are the relative roles of troposphere expansion versus steeper heat gradients in incorporating warming? Others who work in this area can fill me in.

          What doesn’t make sense about your attempt to rehabilitate the comment is the following sequence:

          1. “It is indeed an absolutely central claim of the global warming theory that this height increases when more CO2 is added to the atmosphere.” (RN)

          2. “There are no direct measurements of the most basic aspect of the theory, which is that the CO2 pause is moving outward” (MS)

          3. Therefore skepticism of global warming theory is warranted. (paraphrase of MS)

          Global warming, insofar as it is occurring, can be expected to have a large number of impacts on marine, terrestrial and atmospheric (and tropospheric) systems. Some of these impacts are logically necessary, others probable but also capable of being offset by other factors. It is reasonable to check to see if the necessary impacts are actually occurring, and if it can be shown that some are not, that would be grounds for skepticism. Science feeds on anomalies. But claiming that one such impact lacks direct measurement does not do this. If there are 40 such impacts, and 39 are demonstrably verified, the inability to assess the 40th due to measurement issues is immaterial.

          Remember that all of this is in the context of a set of biogeochemical phenomena that are logical implications of the basic principles of physical science and that have a wealth of corroborating evidence generated across a range of evidence and model types. Why should I care if one implication of the theory resists direct measurement? (And the nonexistence of direct measurement is itself not consequential if a range of independent proxy measures yields sufficient overlap. That was the story of the PETM, which, like all matters of paleoclimatology, is not susceptible to direct measurement: humans weren’t around back then to take temperature and CO2 readings. Instead we have to make inferences from isotope ratios.)

          Sorry about the bot remark, but the CO2 pause line was cryptic, and even giving it the most generous interpretation doesn’t turn it into a meaningful argument.

          • Peter Dorman says:

            ps: The first reference that comes up in a simple Google search is this: https://journals.ametsoc.org/doi/10.1175/JCLI-D-16-0457.1

            It appears the troposphere is behaving itself, at least if you accept modeling, in the absence of “direct”, evidence.

          • Radford Neal says:

            > Global warming, insofar as it is occurring, can be expected to have a large number of impacts on
            > marine, terrestrial and atmospheric (and tropospheric) systems. Some of these impacts are logically
            > necessary, others probable but also capable of being offset by other factors.

            This isn’t just one of numerous possible impacts. It’s directly on the causal chain from increased CO2
            to increased surface temperatures. If it isn’t happening, the whole theory falls apart.

            Now, that doesn’t mean that scientific progress in the area _requires_ that a direct measurement be
            made. If for some reason that’s very difficult, one could rely on other evidence. But it’s certainly a
            weak point.

  7. Terry says:

    The footnote seems to be painting with too broad a brush. I don’t see how you can certify an entire field as “open to inquiry” or dismiss all the dissidents in that field.

    In climate science, as in almost all scientific fields, there are some suspect characters. For instance, one prominent climate scientist filed a lawsuit against a journalist who had questioned his integrity, and in the complaint, he (the scientist) made the false claim that he was a Nobel laureate. I don’t see why we shouldn’t call out bad behavior in climate science as much as we deplore it anywhere else.

    True, climate science has more cranks than most other fields because it is politicized. Goofy statements by politicians, cranks, and activists about climate science deserve derision. And there are many such goofy statements. On both sides.

    I have followed the debate for many years, and I see two results on which there seems to be a consensus: (1) human emissions of carbon dioxide are warming the planet, and (2) the proposed climate accords such as the Paris and Kyoto accords will have virtually no effect on future temperatures.

  8. Z says:

    It could be that climate science is in “crisis” the same way that psychology is in crisis without it being the case that skepticism of human caused global warming is justified. The fact of human caused global warming has been established from a confluence of many streams of evidence and theory. That being so, climate scientists could still overreact to each new simulation study indicating a slightly different warming threshold beyond which flooding will reach a certain level as if it establishes new fact. (I hope they don’t actually do this.) This would be bad PR for climate scientists and not help their credibility with the public, but it should not influence our level of belief in the well established phenomenon of global warming in general. After all, we don’t respond to the psychology community’s credulousness about marginal results such as air rage or power pose by doubting well established results, e.g. and thinking “maybe serotonin plays no role in depression”.

    • Martha (Smith) says:

      In general, I give more credibility to climate research than to psychology research precisely because scientists from many branches of science are involved in it — so that there is likely to be “outside skepticism” from scientists in fields other than those involved in a particular line of research.

      In contrast, the research community in psychology has been more insular ( although in recent years, a fair number of psychology researchers have indeed been listening to criticism from outside the field).

  9. Jonathan (another one) says:

    The influence of politics and the personal priors of recipients of scientific results are the difference here. If there were no potentially actionable and costly implications of climate science research, it would be uncontroversial, or no more controversial than, say, asteroids killing dinosaurs to pick another piece of climate research.

    Do shark attacks affect election results? Ha, ha, good one, bad stats, whatevs. Do planted stories in Facebook affect elections? Same phenomenon, with lines drawn in the sand before anyone even tries to do the research.

  10. Matt Skaggs says:

    I did hijack the thread I suppose, but I am not a bot. The cause tree approach I use is from engineering. It is a rigorous and comprehensive approach that involves far more than tree logic. The theory of AGW is structurally a control volume problem, which means that everything “inside” can be treated as a black box over a sufficient time interval, and the overall performance can be judged by changes to the input and output. You could just as well consider it a control mass problem. The causal tree in this case just controls for all the possible changes to the inputs and outputs. Unfortunately “capacitance” is an issue as well since the control volume could be storing heat over the relatively short modern warming.

    The climate clearly exhibits characteristics of a stable system. By that I mean that mechanisms must exist to regulate temperature through feedbacks that reduce the magnitude of input or output excursions. This is trivially true and not a subject of debate. If it were not true, diurnal temperature swings would eventually lead to excursions in which the oceans would freeze or boil. How does that stability work? We really have a very poor understanding of it.

    So here is the first major problem with AGW: you cannot really understand how a perturbation to an output – in this case a reduction in solar energy radiation – will affect a system unless you have a good grasp of how the system stability is/was being maintained. To flesh this out, consider a slight reduction in global water vapor, which could easily wipe out any increases from CO2. Can we rule out a water vapor cycle that feedbacks from CO2 increases to maintain stability? We absolutely cannot.

    Re: Arrhenius. His basic findings are undisputed of course. But Arrhenius could only guess at the mechanisms that maintain system stability in the climate. Without that knowledge, he was only guessing about how his physical mechanism would affect global temperature.

    There has been some progress on paleotemperature, but not enough to elucidate the stability mechanisms. A new paper just came out that conflicts with the anthropogenic black carbon theory of why the Little Ice Age ended. Now we are back to the proverbial square 1 on that. The evidence suggests it was an internal variability event of similar magnitude to the modern warming but one we do not understand. The best evidence indicates that the medieval warming was just as big as the modern warming, and the Minoan warming was even bigger, yet we really have no clue what caused those excursions. That is what I mean by having an insufficient historical record. We don’t understand climate stability, so how can we understand what will perturb it?

    Sorry that my use of the term “CO2 pause” was confusing. The whole CO2-warming connection is really complicated! Did you know that? CO2 has sharp absorption bands in the mid-infrared. This is the mechanism known as the “greenhouse affect” although the term is misleading. However, the absorption bands are saturated way up in the atmosphere, meaning that incoming solar energy never gets anywhere near most of the CO2. Adding more CO2 has zero DIRECT affect on warming. What this means is that the basic meme of “Arrhenius figured it out and nobody has disputed it” really isn’t right at all. There are a string of assumptions between “CO2 absorbs heat” and “the planet warms,” and some of those assumptions have proven maddeningly difficult to verify.

    I am going to leave off here, but other challenges to my first post above are addressed in my essay that was published at the blog Climate Etc.

    https://judithcurry.com/2014/10/23/root-cause-analysis-of-the-modern-warming/

    FWIW, while my essay was published at a “denier” blog, I am a socialist and I am appalled that humanity is making a one-way run through our stockpile of fossil fuels. The argument for renewable energy barely overlaps with AGW. But I don’t want to hijack the thread again with a new topic!

    • Terry says:

      The theory of AGW is structurally a control volume problem, which means that everything “inside” can be treated as a black box over a sufficient time interval, and the overall performance can be judged by changes to the input and output.

      Does this mean that we can use the historical temperature increase associated with the historical increase in CO2 can be used to estimate the relationship?

      That sounds pretty straightforward, but I have never seen that estimate in the literature. Do you happen to know what that approach predicts for a doubling in CO2? Robert Muller says a historical model using just CO2 and aerosols (IIRC) fits the historical data quite well. Do you know what estimate the Muller model produces?

      • Matt Skaggs says:

        Terry asked:

        “Does this mean that we can use the historical temperature increase associated with the historical increase in CO2 can be used to estimate the relationship?”

        Yes. This is known as an “observationally constrained estimate of ECS,” where ECS is Equilibrium Climate Sensitivity. There is only one researcher focusing directly on this as far as I know, Nic Lewis. Nic’s work comes up with different numbers than the ones you typically see.

        Chris Wilson wrote:
        “Do you honestly think that the scores of physicists, biogeochemists, and climatologists who work on this have simply overlooked basic physics?”

        The person you are attacking seems to be made of straw. Try this:

        http://www.realclimate.org/index.php/archives/2007/06/a-saturated-gassy-argument-part-ii

        This is from the website where the grandees live. I guess my statement of zero effect was not quite right due to a phenomenon known as pressure broadening. With a 4X increase in CO2, you could get a 1% effect. But that is not where AGW comes from.

        • Chris Wilson says:

          I’m sorry Matt, I just don’t think you understand the basic claims of AGW, or the essentially ironclad physics of how the greenhouse effect works. That link is talking about absorption of IR emitted from earths surface, and it’s not clear to me what part of that discussion you are disagreeing with. The key you keep missing is that it is dissipation of heat energy back into space that matters, and does not saturate the way you indirectly imply.

    • Dalton says:

      “However, the absorption bands are saturated way up in the atmosphere, meaning that incoming solar energy never gets anywhere near most of the CO2.”

      Global warming is not (primarily) caused by absorption of incoming solar energy. The problem is outgoing terrestrial radiation. The Earth too is a black body. Radiative cooling by outgoing longwave radiation is the primary way the Earth System loses energy. CO2 is a blanket on that black body which we happen to inhabit.

      The science of global warming is settled. It is not “maddeningly difficult to verify.” I will say this about global warming. “Saving the Earth” is bullshit. The Earth will be fine. It’s civilization you have to worry about. As long as you can get over the misery and suffering of your children and their children until your descendants die out, then there is absolutely nothing “wrong” with global warming. There will be winners and losers and some species and even individual humans (at least in the short term) will do very well. The poor, however, are fucked.

      • Andrew says:

        Dalton:

        Or, as Richard Tol charmingly puts it, “climate change would appear to be an important issue primarily for those who are concerned about the distant future, faraway lands, and remote probabilities.”

        • Chris Wilson says:

          + 1 to both of you. Andrew, I posted this under your original blog about Tol’s paper, but I figure it’s worth moving up to this discussion. Here is a recent paper by Tol. Same meta-analytical claims about 21st century benefits of global warming, and includes this sentence,
          “Moreover, the 11 estimates for warming of 2.5°C indicate that researchers disagree on the sign of the net impact: 3 estimates are positive and 8 are negative. Thus it is unclear whether climate change will lead to a net welfare gain or loss.”

          https://academic.oup.com/reep/article/12/1/4/4804315#110883819

        • yyw says:

          Or as the French protesters of the carbon tax put it, “the president, the government, they talk about the end of the world and we are talking about the end of the month.”

          Either way, the poor are fucked. Civilization will be fine though. We are already equipped to survive the warming as predicted by IPCC models even if we keep polluting, not to mention the scientific advances for controlling climate and for mitigating effects of climate sure to come in the next few decades.

  11. Chris Wilson says:

    “However, the absorption bands are saturated way up in the atmosphere, meaning that incoming solar energy never gets anywhere near most of the CO2. Adding more CO2 has zero DIRECT affect on warming.”
    No no no. The “greenhouse effect” is about GHG absorbing energy re-radiated from earth surface, and then, crucially, *regulating how much gets dissipated back into space*. This rate of dissipation is proportional to concentration of GHG, so your claim about zero direct effect does not follow. In particular, your implication of *greenhouse effect* saturation is simply incorrect.

    Do you honestly think that the scores of physicists, biogeochemists, and climatologists who work on this have simply overlooked basic physics?

  12. Anoneuoid says:

    I remember asking around a few years ago whether any mainstream climate researchers were simulating the climatic results of a possible substantial decrease in global temperature (for whatever reason; asteroid impacts, volcanoes, solar minimum -> more clouds, nuclear winter, just unexplained cycling, take your pick). AFAICT, the answer is no.

    The existence of such a blind spot should make us very concerned about this field.

    • Phil says:

      Anon,
      Global temperature is an output of the climate models, not an input. In principle one could run multiple simulations — “I want to turn down the temperature 4 degrees C, find me different ways to do that, if I allow you to change the this set of parameter values” — but “simulating the …results of a …decrease in global temperature” can’t be done directly.
      However, researchers are looking into ways that the temperature can decrease. For instance, Oxford University has a geoengineering program that looks at using stratospheric aerosols and other methods to decrease global temperature: http://www.geoengineering.ox.ac.uk/what-is-geoengineering/what-is-geoengineering/
      That is just one example. Here is a Scientific American article about this issue: https://www.scientificamerican.com/article/geoengineering-and-climate-change/

      • Anoneuoid says:

        Yes, of course. Basically all the examples I gave would be investigating the effects of a sudden, drastic increase in albedo. Do you have a link to someone using the same climate models to investigate one of these scenarios?

        These people who want to do “geoengineering” and start blocking sunlight or filling the ocean with green goop are scary as hell to most people, btw. I suspect you will get major pushback from across the world if such a project is undertaken because it looks exactly like what a doomsday cult would try to do.

        • I highly recommend Oliver Morton’s “The Planet Remade,” an excellent popular science book about geoengineering (link; my short review, and an excellent popular science book period. One of its major arguments is that one should do small-scale geoengineering soon, to prevent wild and risky geoengineering later. There are also fascinating sections on climate model projections of various geoengineering scenarios.

          • Anoneuoid says:

            I’ve met someone who was (or maybe they knew someone that was) working on geoengineering (had to do with cloud seeding), and was told the research involved heavy use of NHST. So I have little hope for it working out as they plan one way or the other. This isn’t like psychology where no one cares anyway, or medicine where there are millions more potential subjects being created every day.

            From your link:

            It’s a contentious topic for obvious reasons — experiments sometimes go wrong, and experimenting with the planet could have terrible unintended consequences. On the other hand, our present large-scale dumping of carbon dioxide into the atmosphere, from the historical value of about 280 parts per million to the present value of over 400 ppm, also counts as a giant experiment

            I think the two situations are totally different. In the CO2 release case it is happening as a side effect of something that makes human life acutely more pleasant. There may be some chronic bad side effects. The geoengineering being suggested to counteract this isn’t something people would just do on their own, it is more like accepting an untested medical treatment developed completely from theory.

            I am, of course, in favor of measuring what is going on (actually would prefer much better than is currently being done) and for people to continue developing and testing models of various future scenarios.

        • Phil says:

          Anon,
          you ask “Do you have a link to someone using the same climate models to investigate one of these scenarios?”, I just gave you a link! Well, I don’t know for sure that that group at Oxford uses the same climate models that are used for other purposes, but I certainly expect that they do. If you go to Google Scholar and search for ‘geoengineering albedo climate change’ or similar, you will find many papers, some of which use the same climate models that are used for other purposes.

          I certainly hope these geoengineering ‘solutions’ scare other people. They certainly scare me. I was initially very unhappy with even pursuing them, but I think I have bought into the idea that they are worth looking at. The amount of future climate change that is already built into the system is enough to have extremely bad effects, and it doesn’t look like we are going to be substantially reducing greenhouse gas emissions anytime soon, much less getting them low enough to stop the atmospheric concentrations to decrease. We are like heavy smokers, already diagnosed with heart disease and lung cancer, ratcheting up the number of cigarettes per day while deciding that we had better increase our research into heart disease and lung cancer treatments. Conditional on the fact that we are going to continue smoking, perhaps that is a rational decision.

          • Anoneuoid says:

            If you go to Google Scholar and search for ‘geoengineering albedo climate change’ or similar, you will find many papers, some of which use the same climate models that are used for other purposes.

            […]

            The amount of future climate change that is already built into the system is enough to have extremely bad effects

            I am sorry if this sounds too “aggressive”, but to me it sounds like you are totally bought into this catastrophic climate change due to CO2 scenario. However, you are not willing to find a direct link for us regarding what I asked (keep in mind that even if you cannot convince me, the audience of blog readers is far larger).

            Also, it sounds like the only time you expect the models have been used to study cooling is in the case of a (relatively controlled) “geoengineering” context rather than sudden and (supposedly) unexpected event.

            Seems like a niche to be filled if you are in this field, why is no one doing it? What is the collective odds of at least one of volcanic eruption/asteroid impact/solar minimum/nuclear war occurring over the next century. Is it negligible according to current models?

            We are like heavy smokers, already diagnosed with heart disease and lung cancer, ratcheting up the number of cigarettes per day while deciding that we had better increase our research into heart disease and lung cancer treatments.

            This is an interesting analogy because it took cancer researchers at least half a century to reproducibly cause experimental cancer using tobacco smoke (it isn’t hard using other substances like radioactive dust), and in the end they found out that simulating “quitting smoking” was required to make it common enough to detect:

            Strain A mice were exposed first to a comparatively high concentration of ETS, generated from the sidestream (89%) and mainstream (11%) smoke from burning Kentucky 1R4F cigarettes, as described before in detail [9]. After a 5-month exposure, the animals were allowed to recover in air for another 4 months before evaluation of the lung tumor response. The same protocol was eventually adopted by three other laboratories [10–12].
            […]
            The flat dose-response suggests that tobacco smoke is a comparatively weak carcinogen. A previous study in which a dose-response was conducted in one single experiment came to the same conclusion [13]. It may to some extent explain why most inhalation studies done with tobacco smoke in mice failed to give a positive tumor response [14, 15]. The fact that ‘‘only’’ 10% to 25% of all smokers develop lung cancer [16] might also be construed to indicate that tobacco smoke is not a very potent carcinogen in man.

            https://www.ncbi.nlm.nih.gov/pubmed/15765916

            In spite of the dominant role of cigarette smoke (CS) in the epidemiology of lung tumors, tumors at other sites, and other chronic degenerative diseases [1, 2], it is very difficult to reproduce the noxious effects of this complex mixture in animal models.
            […]
            During the last decade, we developed a novel murine model that convincingly reproduces the carcinogenicity of MCS [6] and its modulation under conditions mimicking interventions either in current smokers and/or ex-smokers.
            […]
            Our model involves exposure of mice for 4 months, starting at birth, followed by a period of 3-4 months in filtered air in order to give enough time for the growth of histopathological lesions.

            https://www.ncbi.nlm.nih.gov/pubmed/29370344

            • If a supervolcano eruption, major asteroid impact, or nuclear war occurs, the last thing we’ll care about is CO2 in the atmosphere. In my opinion we can already say “that would be catastrophic and either wipe out the human race or set us back to the Pleistocene” any research we do about it would likely be wiped out when it occurred, and so it doesn’t even help us deal with the possible eventuality. The utility of this research is basically nil because knowing the answer doesn’t help us take any action that could improve things that we aren’t already taking (like… don’t start nuclear wars)

              Now, solar minimums, more minor volcanism, geoengineering, and things like major methane releases from frozen ground etc (ie. moderately extreme events in either cooling or warming direction) are of course something to be studied, and *are* being studied.

              • Anoneuoid says:

                If a supervolcano eruption, major asteroid impact, or nuclear war occurs, the last thing we’ll care about is CO2 in the atmosphere.

                Ok, but the climate models can handle changing something besides CO2 right?

                Now, solar minimums, more minor volcanism, geoengineering, and things like major methane releases from frozen ground etc (ie. moderately extreme events in either cooling or warming direction) are of course something to be studied, and *are* being studied.

                Yes, like what happens if albedo is suddenly increased 5%, 10%, 25%, etc. Where will be the best place to grow food? How many months/years of supplies do we need to put in the underground bunkers. Whatever, it will be a slowly developing disaster.

                I am sure the militaries of the world have something like this for at least the nuclear winter case, but do they use the results of modern GCM’s run on supercomputers?

              • Anoneuoid says:

                I would like to see GCM’s applied to a scenario like this:

                The Late Antique Little Ice Age was a long-lasting Northern Hemisphere cooling period in the 6th and 7th century AD, during the period known as late antiquity. Its existence was proposed as a theory in 2015, and subsequently confirmed as the interval from 536 to about 660 AD.[1] This period followed three immense volcanic eruptions in 536, 540 and 547. One of the suspected volcanic sites for those events is the Rabaul caldera, in the western Pacific, which erupted around 540. The extreme weather events of 535–536 were the early phenomena of the century-long global temperature decline.

                https://en.wikipedia.org/wiki/Late_Antique_Little_Ice_Age

              • If you really care about such things I’m sure googling “late antiquity little ice age gcm” would produce something of interest… let us know.

              • Anoneuoid says:

                If you really care about such things I’m sure googling “late antiquity little ice age gcm” would produce something of interest… let us know.

                Ha: https://i.ibb.co/WKm78rG/liagcm.png

                I mean, there was apparently one of these “little ice ages” around 550 AD, then another that started around 1300 AD [1], so if its due to some cyclical phenomenon we expect another one about 1300 + 750 = 2050 AD…

                https://en.wikipedia.org/wiki/Little_Ice_Age

              • Remove the quotes! Ok done here. I take your point that you are skeptical that truly useful research is going on. I fear you could be right but I do think the basic physics is correct. Lots of academics waste time and resources or chase the latest fads that get funded… Doesn’t mean co2 is benign.

            • >The fact that ‘‘only’’ 10% to 25% of all smokers develop lung >cancer [16] might also be construed to indicate that tobacco >smoke is not a very potent carcinogen in man.

              Sure, it’s nothing like breathing in powdered radioactive substances. People get cancer from cigarettes after 20-50 years of smoking in which they actually inhale the smoke directly on a daily basis! We knew it was a long exposure issue from the start. It didn’t require trying to get a tiny animal whose whole natural lifespan is like 3-5 years to produce a cancer from inhaling secondhand cigarette smoke to tell us that.

              • Anoneuoid says:

                Well, as an aside, I question the use of rodent models regarding anything beyond initial toxicity studies.

                Since any results people don’t like are so easily dismissed then why are we doing it in the first place? It was interesting to learn it is actually easier to increase cancer rates in rodents using exposure to cell phone frequencies than tobacco smoke: https://ntp.niehs.nih.gov/results/areas/cellphones/index.html

                People’s response to the results they don’t like is the same. “Rats/mice are diffenrent than humans”, “the particulars of the exposure are different”, etc. All valid responses, which begs question of why do it to begin with. I’ve seen rats with nearly half their brain missing act normal…

                But the key point was that it turned out to see lung cancer in rodents you needed to allow the tissue to heal. Presumably, during the healing there are many more cell divisions and a general proliferative milieu which is conducive to tumorigenesis.

                Could it be that there are likewise feedbacks in the climate that would respond “poorly” to a sudden reduction in CO2 emissions?

              • “why are we doing it in the first place?”

                The fact that it’s hard to make mice get lung cancer from cigarettes basically confirms the prior, whereas if it turned out to be *easy* then we could potentially look for “what the heck lets human apes smoke for so long without cancer?” which would be an interesting area of research. But once you confirm that mice too require a long-term exposure, it’s probably time to shut down that research. Really the interesting result would have been the counterintuitive one: humans can smoke for 50 years, but mice for only 3 months.

                >Could it be that there are likewise feedbacks in the climate that would respond “poorly” to a sudden reduction in CO2 emissions?

                sure, but if you can calibrate a model to reproduce in some sense what has happened since say 1700 then you can plug in sudden CO2 emissions reductions into it and see what happens. You can’t really do that in the real world more than once ;-)

                I’m not a big fan of the Global Circulation Model (GCM) industry. I think it has its place, but it’s place is to try to investigate things like what you’re talking about: how do the feedbacks work at a general level? Trying to predict the actual future accurately from them is a joke, and the uncertainty involved is so large that it’s been suppressed in the public face of this research. It’s no good to say things like “temperatures could do anything from say falling 8 C to rising 24 C over the next 200 years with the 50% probability interval including -2 to +7” but that could maybe be the level of uncertainty that comes out of these models (though just quantifying that is more computing time than we can really afford), and then we have major political struggles surrounding an imaginary goal of maybe holding temperature change to less than +2C by cutting emissions down to zero or whatever. At the same time, China makes brand new coal powerplants like crazy:

                https://www.theepochtimes.com/china-building-new-coal-plants-equal-to-entire-us-capacity_2679901.html

            • Phil says:

              Anon,
              Evidently you are too lazy to go to Google Scholar and do a search, even when I give you the search terms. If you don’t care enough to do that, I don’t see why I should go to the trouble on your behalf. And now I simply refuse to be goaded into it, even though I have several links sitting before me. You don’t sound ‘aggressive’, you just sound like a bit of a jerk.

              I don’t follow your reasoning regarding asteroid impacts etc. I think you’re saying an asteroid impact is so likely that we should be studying the details of that too? First, although a major asteroid impact is indeed very likely to happen someday, the odds of it happening in the next few hundred years are extremely small. Second, there’s nothing we can do about it anyway.

              And yes, I am ‘totally bought into this catastrophic climate change due to CO2 scenario.’ Of course I think there’s a chance that the researchers have it wrong, but I think that chance is very very small. Things are going to get very bad.

              • Chris Wilson says:

                I’m with you Phil. Plus, from a risk management point of view, the point is that the downside is basically unbounded negative infinity (i.e. human extinction) (before Daniel Lakeland jumps in, yes for a real utility function we will need to just make this a very big negative number :)), whereas any possible upside is VERY bounded, and probably we are already seeing whatever “benefits” there may be.
                In this context, uncertainty per se, especially surrounding the poorly constrained feedbacks, leads us to a much greater negative expected utility than propagating point estimates might suggest (due to Jensen’s inequality).

              • Anoneuoid says:

                Evidently you are too lazy to go to Google Scholar and do a search, even when I give you the search terms.

                Not lazy. I just have too much experience of wasted time going to links/references and not finding what was claimed. My ideal format is seen in this post: http://statmodeling.stat.columbia.edu/2018/12/08/footnote-global-warming/#comment-926112. You can see I even quote the parts I find most relevant to my claims to waste as little of your time as possible.

                I don’t follow your reasoning regarding asteroid impacts etc. I think you’re saying an asteroid impact is so likely that we should be studying the details of that too? First, although a major asteroid impact is indeed very likely to happen someday, the odds of it happening in the next few hundred years are extremely small. Second, there’s nothing we can do about it anyway.

                The asteroid impact was one example of something that (supposedly) could lead to increased albedo (it would lead to dust up in the air blocking sunlight). Perhaps the chances of a relevant impact in the next couple hundred years are small, but what about in addition to the other possible albedo-increasing phenomenon I mentioned? It is disturbing to me that no one seems to be studying this stuff, they are all focused on increasing temperatures.

                It is like the stock market. When everyone thinks something is going to happen, then the opposite they didn’t plan for happens…

              • Phil says:

                Anon,
                I see your point about the references: given that there is a chance I’m wrong about the references I mentioned, you don’t want to waste your time. Why not try to make me waste my time instead? Perhaps twenty seconds of your time to write a few sentences to get me to do the search will lead to getting the reference you want. Worst case is I blow you off, in which case you’ve wasted twenty seconds. Whereas, if you do what I suggest, you might waste forty seconds or even more! You can invest twenty of your seconds to try to get me to invest forty of my seconds, and that must be better (for you) than investing forty seconds of your own! OK, fair enough, your time is obviously far more valuable than mine so it makes sense to get me to do the legwork, if we call a quick internet search ‘legwork.’ Here https://www.pnas.org/content/104/24/9949.short is one of many similar references you could have found in under forty seconds on Google Scholar. I was wrong, I did let you goad me into posting one.

                Researchers are studying the effects of increased albedo and other things that could cause the temperature to decrease instead of increase. It is clearly not _very_ disturbing to you that ‘no one seems to be studying this stuff’: it is very easy to learn that people _are_ studying this stuff, so if you don’t even care enough to check, how disturbed can you be? But even if people weren’t studying this stuff, I’m not sure how much that should disturb you: increasing temperatures are happening now, for reasons that are well understood, and the things that would turn that around would either be rare or deliberate. Your stock market analogy doesn’t really work: it is widely recognized that at any time the stock market is fairly likelty to go either up or down, but it is not widely recognized (and not true) that at any moment the earth is likely to suffer a catastrophic collision with an asteroid, or the start of a long series of eruptions of a supervolcano. But anyway, people are studying at least some of the ways temperatures can be made to decrease. Rest easy.

              • Anoneuoid says:

                Why not try to make me waste my time instead?

                If I want someone to bother with some claim I am making, I do not consider grabbing the references to be a waste of time. So perhaps we just misunderstand each other’s purpose.

                Here https://www.pnas.org/content/104/24/9949.short is one of many similar references you could have found in under forty seconds on Google Scholar. I was wrong, I did let you goad me into posting one.

                It sounds like this is just a random paper you found and haven’t read?

                All they do simulate the sun dimming exactly enough (by 1.6%) to cancel their simulated effect of atmospheric CO2 being doubled. Then: “Global temperatures in the model responded to this geoengineered forcing by returning to preindustrial conditions.”

                This isn’t anything like what would happen in a super volcano, impact, etc scenario.

  13. Anoneuoid says:

    Daniel Lakeland wrote:

    The fact that it’s hard to make mice get lung cancer from cigarettes basically confirms the prior

    This was not at all expected at the time. The previous experience was using radioactive dust, where it was easy to devise an exposure to get 100% of mice developing lung cancer. Based on epidemiological data, tobacco had recently become a big public health issue causing lung cancer left and right. Why would they expect it to be any different than the radioactive dust?

    I also bet if you ask the average person today what they would expect (“would it be easy or hard to cause lung cancer in mice by exposing them to tobacco smoke?”), the majority would guess “easy”.

    once you confirm that mice too require a long-term exposure, it’s probably time to shut down that research

    It isn’t the long exposure that is interesting from the rodent results. It is that you need to start the exposure within hours of birth, expose the mice basically until adulthood, and then stop the exposure for just as long. And even then, it only works for special strains of mice (that either have exceptionally high or low background rates of lung tumors, I forget which).

    • > I also bet if you ask the average person today what they would expect (“would it be easy or hard to cause lung cancer in mice by exposing them to tobacco smoke?”), the majority would guess “easy”.

      If you reworded the question as “given that humans often smoke daily for decades before developing lung cancer would it be easy or hard to cause lung cancer in a mouse given that their entire lifespan is only on average 3 years by exposing them to ambient tobacco smoke?” what would people say?

      how you ask the question matters here.

      • Anoneuoid says:

        You keep ignoring that they have to stop the exposure to get it to work, so your explanation cannot account for what is happening.

        Eg, mice exposed for 8 months apparently do not have lung cancer more often than usual. It only happens if you expose for 4 months, then stop for 4 months to let the tumors grow (or for carcinogenesis to occur, or whatever is going on). Take those numbers as a guesstimate, it is something like that.

        You could also make it seem more likely they would form tumors because the ratio of toxin/tissue is so much higher, or mention there may be higher baseline somatic mutation rates in mice vs men.

  14. Anoneuoid says:

    Daniel Lakeland wrote:

    Remove the quotes! Ok done here. I take your point that you are skeptical that truly useful research is going on. I fear you could be right but I do think the basic physics is correct. Lots of academics waste time and resources or chase the latest fads that get funded… Doesn’t mean co2 is benign.

    I did do the real search. There is no study like that. In particular this “little ice age” has only been studied for like 2 years so it isnt surprising: https://www.nature.com/articles/ngeo2652#affil-auth

    But in general, I still have never seen a GCM study of what may happen climatewise if something like that scenario occurs today. I didn’t search too hard this time but a couple years ago I did put in much more effort.

    Regarding the “basic physics” being correct, that is a necessary but not sufficient requirement for a successful model.

    I can have a great basic physics quantitative model of “higher concentration of salt -> increased osmosis -> higher pressure”, but that doesnt mean I can conclude a high salt diet leads to higher blood pressure (in fact it looks like more salt in the diet is negatively correlated with chronic blood pressure: https://www.fasebj.org/doi/abs/10.1096/fasebj.31.1_supplement.446.6).

    The point is that once you start dealing with feedbacks, etc it is quite easy for the exact opposite of what would be naively expected from “basic physics” to occur. The only thing to do is to come up with a simulation to see how it all works out. Of course, it is possible we can’t constrain the parameters enough. In that case we can’t do better than conclude pretty much “anything can happen” like you say with the GCMs.

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