Uncertainty monster visits MIT

by Judith Curry

This Thursday, I will be visiting the Department of Earth, Atmospheric, and Planetary Sciences (EAPS) at MIT, giving the Victor Starr Lecture.

Some background on Victor Starr and the Lectureship is [here].

Prof. Victor P. Starr was at MIT from 1937-1972, and from 1947 as a faculty member. He had extremely broad interests in the general areas of atmosphere, ocean and planets. Prof. Starr is perhaps best known for his pioneering work in understanding from observations the physics that actually sustains the atmospheric general circulation. He is reputed to have supervised more PhD theses in meteorology than anyone else in the history of MIT. Upon Starr’s death in 1974, the Department established the Victor P. Starr Lectureship. 

The Victor Starr Lecture has been given annually since 1978.  Previous lectures are listed [here].

Here is the title and abstract for my lecture:

Climate Science and the Uncertainty Monster

How to understand and reason about uncertainty in climate science is a topic that is receiving increasing attention in both the scientific and philosophical literature. This talk provides a perspective on exploring ways to understand, assess and reason about uncertainty in climate science, including application to the Intergovernmental Panel on Climate Change (IPCC) assessment reports. Uncertainty associated with climate science and the science-policy interface presents unique challenges owing to complexity of the climate system itself, the potential for adverse socioeconomic impacts of climate change, and politicization of proposed policies to reduce societal vulnerability to climate change. The challenges to handling uncertainty at the science-policy interface are framed using the ‘monster’ metaphor, whereby attempts to tame the monster are described. Uncertainty of climate models is interpreted in the context of model inadequacy, uncertainty in model parameter values, and initial condition uncertainty. The challenges of building confidence in climate models are described. The treatment of uncertainty in the IPCC assessment reports is examined, including the IPCC 4th Assessment Report conclusion regarding the attribution of climate change in the latter half of the 20th century. Ideas for monster taming strategies are discussed for institutions, individual scientists, and communities.

This talk is a revised and expanded version of the talk I presented at the American Chemical Society meeting a few weeks ago.  I received some good comments from the Denizens, and in light of these I have modified my talk to introduce the uncertainty monster earlier, clarify some of the explanations, and provide more personal perspective. I’ve also changed the talk to provide more academic/technical content, given the audience.

The current draft of my talk can be found [hereuncertainty monster mit].  I would certainly appreciate any comments or suggestions.

I’m very much looking forward to my visit.  It will be interesting to see how this audience reacts to my lecture.

409 responses to “Uncertainty monster visits MIT

  1. Where the Wild Things Are.
    ==============

  2. Page 23 and 42 are the same.

  3. Did my monsters not quite make the cut?

  4. Lots of luck with your talk at MIT.

    Will Prof. Lindzen be in the audience?

    It would be interesting to hear his comments.

    • Actually, Lindzen participated in the same ACS session that I did. I will also be at the same meeting as Lindzen at the end of October (more on that soon), so Lindzen will definitely be getting a heavy does of this (assuming he attends my seminar at MIT)

  5. Thank you, thank you, Professor Curry, for taking the Uncertainty Monster to MIT. I wish you well in conveying the message.

    Forty years (1971-2001) of uncertainty in the output of computer models – with freedom to select the output that would lead to a grant renewal – have trapped world leaders, their scientific advisors and thousands of followers — like rats on a sinking ship — with totally false claims of human control over Earth’s climate.

    Meanwhile, new studies are routinely revealing

    a.) The violently unstable nature of Earth’s heat source
    http://www.physorg.com/news/2011-09-sunspot-big-bad.html

    b.) The impact of solar activity (the solar cycle), solar flares and eruptions on the climate of other planets
    http://www.physorg.com/news/2011-09-venus-weather.html

    With kind regards,
    Oliver K. Manuel

    • This sad state of affairs became public in late Nov 2009 when e-mails exposed Big Brother’s toe. The owner was confirmed by leaders of the scientific community, whitewashing the nail and trying to remove stains from its previously sparkling Nobel Prize.

    • The Venus study is interesting. The models of Venus are not so beyond doubt either:

      “In addition to all these changes, we saw warmer temperatures than those predicted for this altitude by the leading accepted model, the Venus International Reference Atmosphere model,” said Kostiuk. “This tells us that we have lots of work to do updating our upper atmospheric circulation model for Venus.”

      my bold

  6. I loved the cartoons. The one with the skeptical princess not wanting to kiss the frog made me laugh out loud. Is there any way the public can hear the lecture itself? I’d love to do so if possible. Will it be taped? I’d especially like to hear any Q+A…

  7. If there is more than 20 people in the crowd why don’t you ask the crowd how many are Republican’s vs. Democrat’s, just for fun.

    Then ask yourself why in a fairly evenly divided political culture it stacks up this way in climate studies?

  8. cwom14 – excellent suggestion.
    I think Mike Hulme’s book (why we disagree about climate change) goes some way to explain the relationship, but getting us to think about how this link/divide works for us is a really telling experiment.

    • Dr. Curry has some “denial” on the topic. I don’t intend to use that word in the usual smearing Godwin Law kind of way found so often on this and many other forums.

  9. Hope to be able to attend; I am due, yea, overdue, for a “mental health” day. Glad your experience with the ACS meeting presentation helped to tune this presentation.

  10. Dr. Curry

    Best wishes and good luck with your presentation. Have fun wrangling them monsters into the corral at MIT.

  11. It looks very interesting and seems to be more explicitly skeptical than previous versions (I don’t recall the previous version including the statements that solar variability does not explain the early 20th century rise and aerosols do not explain the mid century pause). Or is it just that more is written down rather than spoken in this version?

    The remark about IPCC appendix 9.C not existing is interesting. The index at the start of ch 9 says that appendices 9.B-D are available on-line, but this does not seem to be the case. Is this an error that should be reported to the IPCC through its new protocol for error handling?

  12. Chart 30
    Modeling groups selected their preferred forcing data sets using inverse modeling, whereby the magnitude of uncertain parameters is varied in order to provide a best fit to the observational record.􀁺

    This is Curve Fitting and not Modeling.

    Chart 50 “Getting climate science back on track” is an Excellent Chart!

    A major uncertainty monster has not been addressed.

    I want to go back to the major ice age and warming periods and debate the basic theory. Consensus Climate Theory builds ice during the long cold period and then melts it rapidly while warming the earth rapidly. Consensus Climate Theory and Models must show how to get the huge amount of energy that would be required to melt miles thick ice sheets and warm earth this quickly. Ice Volume is calculated as an inverse function of temperature. You cannot build ice sheets at the same temperature that you melt ice sheets and simultaneously warm the earth with small changes in energy due to a little change in CO2, small changes in energy from the sun and small orbit changes. This defies the laws of physics. The uncertainty in this melting and warming is 100%. The basic Theory is flawed. In order to reduce the uncertainty in the future forecasts, we must reduce the uncertainty in understanding the past.

  13. I’m not sure if you’re interested in typo notifications, please ignore this if you’re not, further, I would prefer you not publish this in the comments but I believe that on slide five, bullet 2, the verb “lies” should be “lie” to agree with the subject “both”

    BTW, I’ve become a fan of your reasoned approach to this very important and difficult subject, thanks.

  14. “It is possible that it will be taped, if so I will try to make it publicly available.”

    It would be great if so. A lecture by a credible and respected scientist on climate uncertainty, especially in such a venue, is an important event. The more people who see it the better. And congrats on what I’m assuming is a great honor.

  15. I have an idea for a shorter abstract:

    Weather ‘tis certain or uncertain–that is the question: Whether ‘tis nobler in mind to suffer climate or blame others for ‘the slings and arrows of outrageous’ climate change ‘that flesh is heir to’ ‘tis the calculus of the weak not the strong. To plan and prepare–not as cowards but as travelers—for uncertainty and ‘the heart-ache, and the thousand natural shocks’ that climate brings doth make ‘us rather bear those ills we have.’

  16. Dr. Curry,
    A rhetorical question that I often think about: is AGW a hypothesis or a theory? I tend to set the bar high for theories. They must make nontrivial, refutable predictions about unknown outcomes, and the prediction must be shown to be correct by later experimentation or mathematical proof. My dictionary offers the following: “a theory is a more or less verified or established accounting for known facts or phenomena….a hypothesis is a conjecture put forth as a possible explanation of certain phenomena or relations, and serves as a basis for argument or experimentation by which to reach the truth.”

    • Matt, in reality scientists use the term “theory” in several different ways, one of which is synonymous with hypothesis. In fact the synonymous one is the ordinary language use of the term theory. Your dictionary version is as in “atomic theory,” which refers to more or less settled (verified, established, etc.) science. In that sense the question whether AGW is hypothesis or theory is precisely what the climate debate is all about, so there is no settled answer.

      • One other distinction between the terms: theory is often used to denote a collection of hypotheses

      • Do you have an example of that use? I am not saying you are wrong but I can’t think of a case.

      • from a quick look at the wikipedia http://en.wikipedia.org/wiki/Scientific_theory

        A scientific theory comprises a collection of concepts, including abstractions of observable phenomena expressed as quantifiable properties, together with rules (called scientific laws) that express relationships between observations of such concepts. A scientific theory is constructed to conform to available empirical data about such observations, and is put forth as a principle or body of principles for explaining a class of phenomena.

        there seems to be no agreement on what constitutes a theory

      • “In quantitative studies, one uses theory deductively and places it toward the beginning of the plan for a study. The objective is to test or verify theory. One thus begins the study advancing a theory, collects data to test it, and reflects on whether the theory was confirmed or disconfirmed by the results in the study. The theory becomes a framework for the entire study, an organizing model for the research questions or hypotheses for the data collection procedure” (Creswell, 1994, pp. 87-88).”

        http://des.emory.edu/mfp/proposal.html

      • What constitutes a theory in science is one of the principle questions in philosophy of science. (The theory of theories if you like, which was my specialty.) For example, this Wikipedia version does not include what are called theoretical (or unobservable) entities like bosons. Nor do we observe concepts, as it seems to say. We observe real things.

        Then, even broader than the scientific theory we find the scientific paradigm, first described by Kuhn 50 years ago, which includes rules of practice, central examples, how explanations are formulated, anomalies ignored, etc. In many ways AGW is a proposed paradigm, not just a proposed theory.

      • I like your argument re paradigm, it fits the climate change argument quite well

      • string theory is not proven and so is hypothetical, no?

      • The way that AGW issues dominate the research agenda is very paradigm like. The questions are framed within AGW.

      • David..
        “we observe real things?”

        ya, that’s the theory.

      • I belive the use of “paradigm” is technically valid, but I believe the phrase “paradigm shift” suffers from a huge selection bias. We tend to remember only the good, successful paradigm shifts. I do not think of poor, refuted theories and hypotheses as failed paradigm shifts. Do you?

        The concept of “AGW as a paradigm” It is not central to Judith’s talk. Uncertainty is. Perhaps the true paradigm shift is that there is a “really big Uncertainty Monster” that must not be ignored.

      • Me, I prefer the light is observable theory in preference to the bosons are unobsevable theory, a mistake which is commonplace when philosophers discuss physics.

      • With respect to the ‘global warming’ conjecture that man controls the weather and therefore the climate–i.e., is causing the globe to warm (and/or is causing calamitous ‘climage change’), I think it is more meaningful to say that the null hypothesis of AGW theory has never been rejected. Additionally, many believe AGW theory is nothing more than an the ‘official’ view of government science authoritarians–like the EPA–that has already been falsified by reality because human CO2 has gone up whereas global temperatures have gone down. Interestingly and even the IPCC has admitted temperatures have plateaued.

        :

    • Pedantic point: AGW isn’t necessarily only CO2 or only greenhouse gases; land use issues for example may cause localized AGW (aka UHI). So it’s important to actually spell out which anthropogenic driver(s), before you can even talk about it.

  17. Judy – Good luck with your talk. It is thoughtful, well-informed, and provocative, sprinkled with some nice humor.

    I will register my disagreement here with two points you make. First, I believe that the AR4 statement attributing most warming between 1950 and 2007 to anthropogenic greenhouse gas emissions as “very likely” is justified by the evidence, including evidence cited in at least two or three posts and threads in this blog. The IPCC was very careful in its choice of interval. If they had made the same statement for 1970-2007, they would have been wrong. If they had made it for 1910-2007, they would have been wrong, but 1950-2007 entails a correct attribution (with a 10% chance of being wrong) simply because no other net forcings were strong enough to compete, even with solar and black carbon uncertainties, and the internal natural variations, while displaying amplitudes within the interval, tended toward very little net effect over the entire interval. A 100% attribution would have been inappropriate, but I think there is ample reason based on the evidence alone why most climate scientists agree with “very likely”, with no need to invoke non-scientific influences.

    My second disagreement relates to aerosols, which I believe can fully account for mid-century cooling, as demonstrated by the work of Martin Wild and others. That is not to say that other factors were not also operating, but the evidence on global dimming and brightening obviates a need to depend on such other factors. The hemispheric anomalies are consistent. The NH showed a flat to slightly declining trend. On the other hand, the SH, after a 1945-1950 abrupt dip that was most probably attributable to internal climate fluctuations, showed a mid-century warming trend. One can speculate about the cause(s) of the dip, which was present in both hemispheres but larger in the SH (which has more ocean subject to ocean oscillations), but I believe it would be an overstatement to claim the observed data to be inconsistent with an aerosol explanation for most of the mid-century temperature trend.

    I’ll look forward to hearing about the feedback you experience from your talk. I’m confident it will be positive.

    • Fred Moolten

      You argue:

      I believe that the AR4 statement attributing most warming between 1950 and 2007 to anthropogenic greenhouse gas emissions as “very likely” is justified by the evidence…simply because no other net forcings were strong enough to compete

      If you think about this a bit, Fred, I believe you will recognize that it is an “argument from ignorance” (i.e. “we can only explain it if we assume…”).

      Max

      • Fred

        A second point.

        Did IPCC “cherry pick” the period 1950-2005 because it showed warming, which the models could purportedly only explain by including anthropogenic forcing?

        In AR4 IPCC “redefined” the 20th century to cover the period 1906 to 2005.

        It picked the last 55 years of this period for its statement.

        However, it failed to mention that the first 45 years of the period (1906 to 1950) showed a period of statistically indistinguishable warming: a decadal warming rate of 0.104 versus 0.108°C, for which the IPCC models have no exlanation.

        So the logic goes.

        – Our models cannot explain the early 20th century warming

        – We know that late 20th century warming was largely caused by anthropogenic forcing

        – How do we know this?

        – Because our models cannot explain it any other way.

        (Argumentum ad ignorantiam)

        Max

      • PS This was all pretty well pointed out in Judith’s earlier thread on the mid-century cooling.

        If one looks at AR4 FAQ 8.1, Figure 1, one sees that the simulations produced by 14 different climate models were good in simulating the 1975-2005 warming, but did not simulate well either the 1910-1944 warming nor the 1945-1975 cooling.
        http://www.ipcc.ch/publications_and_data/ar4/wg1/en/faq-8-1.html

        A “batting average” of 0.333 may be acceptable in baseball, but doesn’t sound too convincing to me for climate model simulations.

        Max

      • Max- the observational data justifying the AR4 attribution have been discussed in several previous threads. If you visit them, I think you’ll see why there is the general agreement within climate science as cited by Judith that ghg forcing (based on known values) very likely accounts for most of the 1950-2007 warming, and why the other observed forcings plus natural fluctuations do not. This has now become somewhat repetitive, which is why I recommend going back to the earlier discussions. The only important assumptions are that the data are reasonably accurate and that no completely unsuspected and unmeasured phenomenon accounted for significant warming. Something like that can never be completely excluded, which is why “very likely” is a reasonable conclusion but “100 percent certain” would not be.

      • Fred Moolten

        I have “gone back to the earlier discussion” and found exactly what I pointed out earlier.

        The hand-picked period cited by IPCC may well match GCM simulations, but the other two periods within the 20th century clearly do not.

        The argument “our models can only explain it if we assume…” is not a convincing argument for one of the three periods, and even less so if the “models cannot explain” the other two periods.

        This reasoning (among other things) is why our host has problems accepting the IPCC “most warming is very likely due to…” claim as it is written.

        A more correct and honest sentence would have been:

        While there are still great uncertainties regarding the natural or anthropogenic causes of the multi-decadal warming and cooling cycles observed over the late 19th and 20th centuries, simulations from several climate models seem to suggest that the late 20th century warming cycle may well be attributed to a large extent to increases in anthropogenic greenhouse gases.

        .

        This would have been more accurate, but it would not have sounded nearly as “scary” – would it?

        Max

      • It’s much less model dependent than you assume, Max, because the forcings are competing with each other. Their roles are therefore defined by their relative rather than absolute strength. When this principle is combined with the small net effect over the entire interval of known natural variations, the predominance of the GHG effect seems clear, with the usual qualifications about the accuracy of data and the possibility of unknown variables. I’ve always thought that this has been one of the least challengeable of IPCC conclusions. It’s quite solid, and there are other IPCC inferences that I see as more doubtful.

      • Fred Moolten

        When this principle is combined with the small net effect over the entire interval of known natural variations, the predominance of the GHG effect seems clear

        Operative word here is known.

        And to known we can add and acknowledged by IPCC.

        See my post at bottom of thread regarding a natural forcing that is now known but not acknowledged by IPCC.

        Max

      • Fred Moolten wrote: The only important assumptions are that the data are reasonably accurate and that no completely unsuspected and unmeasured phenomenon accounted for significant warming.

        And in particular, that the mechanism(s) that produced the 1910-1940 warming and the end of the little ice age is (are) not in operation.

        Or, if the natural process is something cyclical plus something monotonic operating ever since LIA, then ghg is a “very unlikely” forcing for the “1950-2007″ warming. Your phrase “completely unsuspected and unmeasured phenomenon” is quite misleading, as it is widely suspected and partially measured.

      • MattStat – I intended my response to be here, but I think I forgot to click on reply and so it ended up down here. Basically, my point is that we know with high confidence what was and was not operating between 1950 and 2007.

      • “Basically, my point is that we know with high confidence what was and was not operating between 1950 and 2007.”

        People may well be confident they are correct, but as science shows time and time again, they rarely are. The climate has been generally warming for 300 years. There are many theories but no proofs why that is the case.

        During the 300 years of warming, human society has enjoyed the greatest increase in prosperity and longevity every recorded in history. Again there are many theories why this is the case, but no proofs.

        The notion that we can be “confident” one theory is correct as another is not is not scientific. At one time science was confident the earth was the center of the universe. The idea that Africa and South America had once been joined was considered preposterous. That the irregularity in the earths orbits was not sufficient to cause ice ages. Why the 100k year cycle is dominant, etc. etc. etc.

      • the value in science is how well it can predict. Nothing more. Philosophy deals in explanations. Science is prediction. If your theory can’t predict it isn’t science. The accuracy of the prediction gives the value of the theory. Until the prediction has been validated NO CONFIDENCE can be assigned to the theory. Since 1998 CO2 levels have been accelerating while temperature has not. Contrary to the predictions, which in any other field would argue strongly against the theory being of any value.

      • You can choose data to make a curve fit match.
        Matching data does not prove that a curve fit is a valid model.

      • This is a gross mischaracterization of how scientists operate. I may have a system that is 99% certain to be correctly modeled as an RC circuit, but I may have no way of measuring R or C separately (or their thermodynamic counterparts if RC is just an analogy in this case), other than to observe its behavior.

        In such a situation the best simultaneous estimate of R and C is obtained by performing a least-squares fit of an exponential of the form exp(at+b) to the observed flow of current into the system. The values of a and b for that fit then provide a simultaneous estimate of R and C.

        This sort of situation arises all the time in science, sometimes with one parameter, sometimes two, or three, or more.

        In the case of heat flow from the atmosphere into the ground, we may wish to estimate simultaneously the heat capacity C of the ground underfoot, as a lumped quantity, and simultaneously the thermal conductivity of that ground, also lumped. One way to do this is to artificially increase the temperature at the surface by a calibrated amount, and monitor the resulting heat flux through say the top meter, for a period of a month say. An exponentially decaying rate of flow should result, and we can then read useful information from this flow, thinking of the ground below as a form of transmission line for heat instead of electricity. We can repeat this sort of measurement at different terrains and in this way start to build up a useful picture of thermal conductance and heat capacity.

  18. Very good. I didn’t notice anything specific about appropriate attribution to weather events.

    & I found a collection of quotes about the problem with statistical significance and null hypothesis that someone might find interesting. http://warnercnr.colostate.edu/~anderson/nester.html

  19. Good Luck Dr. Curry.

    I would wish that you would point out at the start of the lecture something that always seems to get left out. Perhaps it would be better at the end. It is about policy though. It is the fact that we are all literally in this together. Several of your slides show what team work is there and what team work is missing. Whether one likes or dislikes a person, think of your worst character, or heretic of choice, all but the smaller number of humans, will have input, directly or indirectly in this issue. To me one of the Achilles heels of these discussions, is that we say we recognize this fundamental fact, yet the arguments made often seek to destroy the fabric of that understanding. In fact, I think this is where those who wish to communicate better are misjudging the atmosphere of the discussions. The focus should be on making the discussion more inclusive, not more and louder. You do this well in slide 24 in your inclusion, as well as your heretic picture, which gave me as big a laugh as the princess and the frog. Your slides illustrate this inclusiveness well. Perhaps a bold statement of “We have to be inclusive of different points of view if climate science is to be successful outside of academia, lest we misunderstand the actual arguments being made in public.” is warranted.

    • It is the fact that we are all literally in this together.

      No we’re not. As estimated from the previous thread about personality types, 97% of the commenters on this blog are skeptical that there’s any serious threat from AGW. Those who do see a threat are in the position of believing they’re on a sinking ship while everyone on deck around them is calling them stupid for believing any such thing.

      We are most definitely not all “in this” together. The 97% don’t see any “this” to be in, there is no problem according to them.

      • Vaughan

        You raise a key point and I am interested in your perspective. What information do you rely upon to evaluate the overall long term impact of a slightly warmer world ?

      • What information do you rely upon to evaluate the overall long term impact of a slightly warmer world ?

        Since that’s not what I do, I guess I can safely say “none.”

        What I do is estimate the present and future impact of human population on, primarily, global temperature and ocean carbonate levels, though other impacts are also of interest to me.

        The information I use for that is the most reliable modern data to hand, in combination with our understanding of the relevant physical and chemical mechanisms, analyzed with statistical and other mathematical tools, and pieced together with the tools and insights of logic.

        Note that I’m not claiming the data is 100% reliable. The climate skeptic’s excuse that we should ignore global warming on the ground that the data may be unreliable is illogical. Data is never completely reliable, but from an evolutionary standpoint those species that ignore the data they do have aren’t in a good position to compete with those that pay attention to it.

        I ignore paleoclimate data because its time constants are too different from modern warming to calibrate us as well as modern data can. CO2 is currently increasing at 240 ppmv per century, a rate that itself is increasing, and there is no evidence of or reason to suspect such a rate at any previous time in the last 100 million years if not the whole lifetime of the planet. Paleoclimate currently offers no examples of what such a rate can do to the planet.

        I ignore complex models of ocean-atmosphere circulation because they constitute uncalibrated dead reckoning, navigation in the dark, which is even worse than paleoclimate. The latter at least offers the opportunity to compensate for its time constants, and I would therefore be extremely interested in ongoing research along those lines if there is any, though I would still attach less significance to it than modern data.

        Sorry to have answered a slight different question about the information I rely on than the one you asked, but it’s the best I can offer when the question of what I do is being begged.

      • @Vaughan Pratt | October 2, 2011 at 1:05 pm

        CO2 is currently increasing at 240 ppmv per century, a rate that itself is increasing, and there is no evidence of or reason to suspect such a rate at any previous time in the last 100 million years if not the whole lifetime of the planet. Paleoclimate currently offers no examples of what such a rate can do to the planet.

        Actually, IIRC, some form of major change to the carbon situation is one of the hypotheses for explaining the end-Permian extinction. The scenario that immediately came to my mind on first reading of this was the opening of a very large coal deposit to rapid erosion. My understanding of evolutionary ecology (such as it is) strongly suggests that fast-evolving clades would have quickly adapted to using this new source of energy in place of (or along with) sunlight.

        This is not to say that I totally subscribe to the need for some “explanation” for extinction events such as the end-Permian. IMO internal variation could well have been responsible. But so could a massive deposit of fossil carbon into the system.

      • Dr. Pratt,

        I some how got involved with a discussion on how Monckton may have estimated climate sensitivity from the old K&T cartoon over at Lucia’s.

        Since I dropped out of the “real” world to fish, my partial differential equations skills are a little rusty. I gave her an abstract physical justification, but would like a little back-up from someone who is not brain dead, http://rankexploits.com/musings/2011/monckton-neither-0-15-wk-m2-nor-0-18-wk-m2-are-the-kt-implicit-planck-parameter/#comment-82829

        It is pretty simple really, latent, sensible and radiative fluxes are dependent on different variables that change with density, temperature differential and emissivity (those are the more significant relationships, there are a few more of course). These would justify using a proportional estimate of temperature change to an impulse perturbation of emissivity to estimate transient sensitivity at the surface and atmosphere with not feedback.

      • Dallas – while you await a response from Vaughan Pratt, I thought I’d offer a couple of thoughts. Convective mixing tends to ensure the maintenance in the troposphere of an adiabatic (isentropic) lapse rate governed by the hydrostatic equation. If we differentiate the SB equation, we find that a 3.7 W/m^2 imbalance at the tropopause translates into a 1 C warming at a radiating temperature of 255 K. The lapse rate then translates this to 1 C at other altitudes including the surface. (The models, by incorporating heterogeneities in their estimates, yield a value of 1.2 C, which is slightly but not dramatically higher). This is a no-feedback sensitivity value, and would be amplified by positive feedbacks not incorporated into the original calculations. There is also a tendency under some conditions for near surface air to warm disproportionately compared with higher altitudes, but convection ensures the restoration of an adiabat. Similarly, there are circumstances where disproportionately less warming is observed, but there is no evidence for this as a general tendency. Note though that while the physics of the lapse rate dictate the same temperature change independent of altitude, they do NOT dictate the same flux imbalances. In fact, the KT energy budget explains why the flux imbalances will differ, with back radiation playing an important role. A 1 C temperature rise at the surface corresponds to about a 6 W/m^2 surface flux imbalance, not 3.7. In fact, given the KT structure, a 3.7 imbalance at the tropopause is incompatible with a 3.7 imbalance at the surface.

        One convenient way to think of this is to see temperature changes as responses to imbalances between planetary incoming and outgoing energy (typically measured at the tropopause) with the surface “dragged along” in response to the incoming/outgoing imbalance.

      • The Certainty Monster.
        =========

      • Hey Fred,

        Yeah, I come up with about 0.8 with the Monchton estimate, not far off really, given that he was using the old K&T. The question is the validity of the estimate. To me it is just as accurate as assuming an emissivity and using S-B as long as the range is limited. It is basically an interpolation. Anyway, that appears to be how Monchton got his numbers, which should be a little low because averaging cyclic day latent/thermal values with more constant radiative values would bias it low.

        The funny thing is Lucia thinks that 288K has to be used but the change from 255K to 288K is the interpolation range.

      • @Dallas I gave her an abstract physical justification, but would like a little back-up from someone who is not brain dead, http://rankexploits.com/musings/2011/monckton-neither-0-15-wk-m2-nor-0-18-wk-m2-are-the-kt-implicit-planck-parameter/#comment-82829

        Rotten timing, you caught me when I was feeling brain dead. ;)

        Meanwhile if I understand the discussion between you and Fred, you’ve decided that Monckton’s math is not as wildly wrong as Lucia was claiming. While I didn’t have the energy this morning to wade through the whole thread preceding your comment, I did at least take in the first half dozen lines where Lucia objected stridently to Monckton’s perfectly fine formula dT/dF = T/4F. I used the same formula in my response to PMH commenting on my mid-August post to Climate Etc. on DLR, in its reciprocal form dF/dT = 4F/T.

        Lucia’s dismissive reaction to this formula was reminiscent of David N’s more polite reaction to my use of it, viz. “I also have a problem with this part of Pratt’s comment”. To which Chris Colose responded “Yes” which I took to mean he too had a problem with the formula. While it wasn’t my intent, it seems like a great formula to embarrass the unwary with, which makes one wonder whether Monckton had this in mind.

        A fair amount of discussion of my use of the formula followed, with some of the confusion resulting from my lack of clarity in my intended denotation of flux F and temperature T, easily cleared up however once it became clear that was part of the problem. Also Arthur Smith wanted to know what dF/dT had to do with rates of change, the answer being that it provides the conversion factor for converting the rate dT/dt to the rate dF/dt (where T is temperature and t is time), namely dF/dt = dF/dT * dT/dt. I think eventually most realized that dF/dT = 4F/T was perfectly fine in theory.

        In practice 4F/T is also a convenient form for dF/dT since (a) it’s linear in each of F and T instead of being cubic in T, and (for me at least) therefore a better source of insight, and (b) neatly sidesteps the Stefan-Boltzmann constant σ. It also provides a nice example of a separable differential equation, having the form dF/F = 4dT/T after separation of variables. Integrating both sides, one gets ln(F) = 4 ln(T) + C where C is the constant of integration. Exponentiating both sides we come full circle to recover the Stefan-Boltzmann formula F = σT^4 where σ = exp(C) = 5.67E-8. This technique when applicable is worth bearing in mind when you’re given a relationship in differential form and want it in a more explicit form, aka a solution to the given differential equation.

        Sometimes 15 error reports from the compiler all disappear when a single missing parenthesis is supplied, making it easier to fix the first error reported by the compiler and resubmit the program than to spend time diagnosing the other 14 errors. I felt that way about everything in the thread preceding your question to Lucia, and didn’t want to spend time figuring out the context of your question as long as it contained bugs right from the get-go. It also gave me little confidence that Lucia’s sarcasm was any more justified for your comment than it had been for Monckton’s use of dT/dF = T/4F.

        What dT/dF has to do with climate sensitivity is a much more delicate issue that would more than double the length of this comment while quadrupling the hot water it would get me into. ;)

      • ::grin:: Sometimes I think you’re alright.
        ===========

      • Vaughan – There’s nothing wrong with T/4F as long as you put in the correct values for T (255 K) and F(239 W/m^2). Monckton tried to pull a fast one by glossing over the fact that he was substituting his own concoction of surface heat fluxes for F and surface temperature for T, while pretending he was recalculating a Planck parameter used to define the relationship between a flux imbalance at the tropopause and a change in radiating temperature (in the absence of feedbacks). He can use any values he wants, but it’s a different parameter, and if used the way he chose, wouldn’t change climate sensitivity estimates despite his false claim to the contrary.

      • It occurs to me that if one writes the above differential equation as
        dF/4F = dT/T
        then its integration as
        ln(F)/4 = ln(T) + C
        ends up with the constant of integration C being −4.1714 in the case of the Stefan-Boltzmann solution to the above equation. This is a more reasonably sized number than σ = 0.0000000567 = exp(-4*4.1714).

        The other way to get a reasonably sized Stefan-Boltzmann constant is to work with temperature units of HK = 100 K, for example taking the melting point of ice to be 2.7315 HK, while still sticking with W/m2 for flux density. The constant is then simply 5.67.

      • Vaughan, “The other way to get a reasonably sized Stefan-Boltzmann constant is to work with temperature units of HK = 100 K, for example taking the melting point of ice to be 2.7315 HK, while still sticking with W/m2 for flux density. The constant is then simply 5.67.”

        Now you tell me after I finally got my spread sheet to do kinda what I wanted :)

        I may be misinterpreting the value of the practical use, but kinda looks like some kick butt regional warming instead of global.

      • Monckton tried to pull a fast one by glossing over the fact that he was substituting his own concoction of surface heat fluxes for F and surface temperature for T

        Thanks, Fred, glad you had the energy to track this down. Yet another candidate for John Cook’s large collection of skeptic arguments. (I also believe he’s missing Harry Huffman’s very slick proof that Venus has no greenhouse effect which depends on neglecting the difference in albedo between Earth and Venus, 0.3 vs. 0.7.)

        Had Monckton’s argument been sound, one might have wondered if he were undergoing a midlife crisis, of the sort those more focused on climate than climax turn to instead of a mistress.

      • Vaughan, Do you really accept Earth’s albedo as a single constant/average?

      • Vaughan, “What dT/dF has to do with climate sensitivity is a much more delicate issue that would more than double the length of this comment while quadrupling the hot water it would get me into.”

        Thanks for the response. I didn’t get into the derivation, just what kind of estimates it would provide, it seemed quite reasonable, but not particularly appropriate for global average fluxes off of a cartoon. I am letting it lay for a while, but it was interesting enough to spend some more time on.

      • Dallas will catch a big one next time he goes fishing, and throw it back.

        To be caught another day.
        ===========

      • We are on the same ship (Earth), but that leaves to issues open for disagreement:

        – What’s going to happen to the Earth?

        – What means “sinking” in the case of Earth?

        Few people expect a full catastrophe comparable to sinking of the ship, while many more take seriously the risk of major damage to the living conditions. Major damage to the living conditions differs essentially from the total catastrophe as it makes sense to compare even major damage to other serious problems of humankind.

      • Pekka

        I agree that many believe there will be serious damage as a result of humans releasing CO2, and that they wish actions to be taken now in order to prevent these potential harms from happening.

        Where I am mystified is in the leap to the conclusions that the warmer world is necessarily worse for humanity overall over the long term or in the economic justification of many proposed actions.

        Added to this basic confusion is a more specific confusion of some of these same people expecting taxpayers of individual nations to support taking steps that may actually harm their country in order to maybe, potentially serve the greater good long term.

      • Added to this basic confusion is a more specific confusion of some of these same people expecting taxpayers of individual nations to support taking steps that may actually harm their country in order to maybe, potentially serve the greater good long term.

        The first hypothesis that leaps (and has since 1998) to my (possibly paranoid) mind is that the need for enforcing such international cooperation would almost certainly further any internationalist agenda.

  20. Fred,

    How do you know that the warming from 1950 -2007 was not due to heat sneaking out of the deep oceans that had been secreted there during the mid-century cooling period?

    Why would IPCC have been wrong, if they had stated that the warming from 1970-2007 was “very likely” due to anthropogenic CO2 emissions?

    Aren’t you just saying that the IPCC is cherry-picking, when they zero in on 1950-2007?

    • Don – I think that if the IPCC had chosen to address only 1950-2007, that would have been cherry picking, as you suggest. However, they have analyzed multiple intervals, and I see them as having chosen 1950-2007 as one interval where their attribution was justified in contrast to other intervals where they could not have made the same claim.

      Regarding the oceans, in an unrealistically hypothetical scenario where some climate influence abruptly forces surface temperature down well below previous levels and then subsides, heat stored in the oceans could then cause the temperature to rise again toward the previous levels. However, mid-century temperatures were flat but not extremely cold compared with earlier, and the warming after 1950 (mostly after 1976) raised temperatures beyond pre-1950 levels in the century as well as the previous century, and so the oceans could not have been warm enough to do that – they would have had to have been much hotter than the surface, for which there is neither evidence nor mechanism.

      • Sorry I forgot to answer your question about 1970-2007. The warming then was accelerated above the drive from GHG forcing because it included a recovery from the earlier aerosol effects. In other words, 1950-1976 spuriously understated GHG effects and 1976-2007 exaggerated them. These two conflicting effects nullify each other over the entire interval, which started without the excess aerosols and ended without them..

      • the nullifying effect seems to be larger in the SH, which to me tends to nullify that particular argument

      • I disagree. For most of the mid-century, the SH shows a slight warming trend while the NH shows a flat or slightly cooling trend. This follows a brief interval immediately after 1945 when temperature registered an abrupt dip. However, the dip is unlikely to be aerosol related, particularly given its short duration and coincidence with internal ocean mode fluctuations, and its greater magnitude in the SH may reflect the larger ocean extent there. Other than that, the SH mid-century shows warming compared with the NH flatness, which I see as consistent with the observational data showing a reduced transmission of solar irradiance to the surface from mid-century until the late 1970s, and a brightening thereafter into the 1990s. The recovery from the dimming is also less marked (less of a trend change) in the SH.

      • Fred,

        My first question was semi-facetious. I know that there was no heat hiding in the ocean depths, just as there is none hiding there now. But certain advocates will pull that story out of their behinds to explain the “missing heat”. And those same characters claim that CO2 is the only explanation for the warming from 1950-2007, because they can’t think of anything else. Their imaginations fail them, when it suits their purpose.

      • I know that there was no heat hiding in the ocean depths, just as there is none hiding there now.

        While I try to stay informed about these things, clearly you’re doing a better job than me. Please plug me into your sources!

        My understanding is that, after reflection, Earth receives around 3.7 x 10^24 joules per year from the Sun, while the heat capacity of the oceans is about 5.5 x 10^24 joules per degree of warming. Over 99% of the heat warming the Earth is radiated back to space, leaving only enough to raise the oceans’ temperature by something like one twentieth of a degree per decade.

        Since the observed warming of the surface has been well over three times this much over the past half century, it follows that the ocean has abundant capacity to “hide the heat” as you put it. Given this, how are you able to tell that it isn’t hiding any heat? You are miles ahead of me here.

        And those same characters claim that CO2 is the only explanation for the warming from 1950-2007, because they can’t think of anything else. Their imaginations fail them, when it suits their purpose

        What is this “something else” that you’ve been able to imagine as the explanation that you claim they couldn’t?

        You apparently have a more active imagination than either the professional climate scientists or us amateurs on the sidelines trying to figure out which side of the climate debate is making more sense. Currently you’re well ahead on imagination points, add some science and you’ve got it nailed!

  21. Will this be open to the public? I might get out my old pocket protector and slide rule and sneak in.

    • As far as I know, it is open to the public. if you do make it, pls be sure to say hi and introduce yourself

    • Ah, memories. You prompted me to look at my 12″ Post Versalog hemmi bamboo slide rule just now; the slide still slides.

      That was back in the days before Archimedes had a Principle. :)

      • Having to keep track of the decimals, I did the maths in my head along with the bamboo and ivory rule, catching reasoning errors along the way. Everyone else just put down the output of their calculators, so it was easy to score top.

        Hmmm. I may not have to look very hard to find the metaphor in there.
        ================

      • That was back in the days before Archimedes had a Principle.

        And after Archimedes came principle inflation. Eventually it got to the point where Groucho Marx could say “Those are my principles. If you don’t like them… well, I have others.”

  22. Dr. Curry,
    Best wishes on your visit. I hope it is constructive and effective.

  23. See you tomorrow (MIT was my safety school)

    • MIT was my safety school

      Applying from Australia, MIT was my second choice for grad school. I didn’t make it (nor to Harvard, my first choice), and had to settle later on for a tenure track slot there. I was one of several MIT faculty back then whom they’d turned down for grad school. Go figure.

  24. Dr. Curry,

    I cannot stress too strongly my opinion that you would benefit greatly from reading the books Wisdom of Crowds and Future Babble. As one of your slides implies, the strong effort to try to achieve a consensus actually works against the likelihood that the consensus will be accurate. In this case, it was more like a steamroller. And as Tetlock’s research (the subject of Future Babble) and the lessons of history demonstrate, expert predictions are no better than a chimp throwing darts. Everything psychology has to teach us (see e.g. cognitive dissonance) screams at us to view the scientific “consensus” with a large mountain of salt.

    Even if one knew nothing at all about the problems with the science (which are legion), history and social psychology would tell us to be skeptical.

    • thx, will check these out

    • I cannot stress too strongly my opinion that you would benefit greatly from reading the books Wisdom of Crowds

      I cannot stress too strongly my opinion that you would benefit greatly from reading the book Extraordinary Popular Delusions & the Madness of Crowds by Charles Mackay. This terrific compendium of examples, first written in 1841, has been greatly expanded in the intervening 170 years with an ongoing harrowing series of yet more examples of crowd madness.

      Those who trust crowd logic are themselves mad. Those who don’t stand a good chance of making a bundle if they play their cards right.

      I estimate that fully 97% of the crowd posting to this blog are mad. ;)

  25. Twice in your slide presentation you state.
    “97% of climate experts agree with this statement (Anderegg et al. 2010)”

    Per my understanding this really should be
    97% of climate experts ‘most actively publishing in the field’ agree with this
    statement (Anderegg et al. 2010)

    Since the actual numbers are 903 who accept AGW, and 472 who reject it. That gives us a percentage of researchers who believe in ACC of about 66%.
    See – http://climatequotes.com/2011/03/27/is-it-97-or-66-of-climate-scientists-who-believe-in-agw/

    The author questioned Anderegg about this and he was nice enough to reply. He acknowledges that his paper doesn’t look at all climate scientists, only at the most active publishers. However, he wants to make clear that the 1,372 number is not representative of the total number of scientists (and so the 66% number isn’t correct). Here is part of his response:

    • Judith
      Compliments on improved/tighter technical summary.

      Re: Page 42/51
      1) Re: “97% of scientists agree with this statement”
      Recommend adding the source numbers to give the context:
      (75 thought humans contributed to global warming since the pre-
      1800s, out of 77 selected from 3,146 earth scientists surveyed.)

      or “from 10,257 earth scientists surveyed”
      or “”experts” vs 82% of all 3,146 earth scientists surveyed.)”

      See the original summary paper:
      Examining the Scientific Consensus on Climate Change Peter T . Doran and Maggie Kendall Zimmerman, EOS V. 90 N. 3 20 JAN. 2009.

      An invitation to participate in the survey was sent to 10,257 Earth scientists. . . .With 3146 individuals completing the survey . . .
      two primary questions . . .
      1. When compared with pre-1800s levels, do you think that mean global temperatures have generally risen, fallen, or remained relatively constant?
      2. Do you think human activity is a significant contributing factor in changing mean global temperatures? . . .
      overall, 90% of participants answered “risen” to question 1 and 82% answered yes to question 2. . . .
      In our survey, the most specialized and knowledgeable respondents (with regard to climate change) are those who listed climate science as their area of expertise and who also have published more than 50% of their recent peer-reviewed papers on the subject of climate change (79 individuals in total). Of these specialists, 96.2% (76 of 79) answered “risen” to question 1 and 97.4% (75 of 77) answered yes to question 2.

      For commentary see:
      Lawrence Solomon: 97% cooked stats Financial Post

      2) Re: “Key finding”
      Change to “Key position” or “Key summary”
      (That “very likely” executive summary statement does not reflect the technical “findings” of most report sections, which blandly state much higher uncertainties.)

      • Judith
        Similar results from the paper you actually cited:
        Expert credibility in climate change William R. L. Anderegg et al. PNAS
        http://www.pnas.org/cgi/doi/10.1073/pnas.1003187107

        the primary conclusions of the Intergovernmental Panel on Climate Change (IPCC): anthropogenic greenhouse gases have been responsible for “most” of the unequivocal” warming of the Earth’s average global temperature over the second half of the 20th century (1–3). . . .
        a broad assessment of the relative credibility of researchers convinced by the evidence (CE) of ACC and those unconvinced by the evidence (UE) of ACC. . . .
        The UE group comprises only 2% of the top 50 climate researchers as ranked by expertise (number of climate publications), 3% of researchers of the top 100, and 2.5% of the top 200,

        So recommend adding:
        (97 of 100 most published of 1,372 climate researchers surveyed)

      • David, this was an excellent summary post and links. Spin polls happen on all sides all the time for media distribution for connected allies. It’s human nature but what is appauling is the willful support it finds among the better informed participants, in this case many of the hardcore consensus advocates inside the science community. The 97% fiction might exist in certain blogs but the idea that it finds traction among actual consensus players is pathetic.

        There is also the issue of word distruction (significant) and muddling warming with causation related. I don’t think Dr. Curry has a good record on this particular topic of false consensus agreements and the spin that is applied. Should we assume she didn’t know the contortion of the 97%-98% quote she had in her slides?

        Why does she get a free pass on this topic?

      • cwon14
        Re:”Should we assume she didn’t know the contortion of the 97%-98% quote”
        No, I would not assume that. I think it was put in as an example of the:

        Scientific perils of overconfidence and
        uncertainty hiding/simplification

        I find the 97%-98% to be an example of the bias generated by funding feedback – those who publish the most – who raise the most alarms – persuade the politicians to give them the most funds. – Bad news sells.

        See Richard Courtney on the Global Warming: How it all began where Prime Minister Thatcher began the global warming bandwagon as a tool against the coal unions and to promote nuclear power.

    • Since the actual numbers are 903 who accept AGW, and 472 who reject it. That gives us a percentage of researchers who believe in ACC of about 66%.

      This is completely bogus. In “Supporting Information,” Anderegg et al say “We define UE [Unconvinced by the Evidence] researchers as those who have signed reputable statements strongly dissenting from the views of the IPCC.”

      By this definition anyone and their dog signing any dissenting statement that Anderegg et al judge to be “reputable” becomes a “UE researcher.”

      This would be ok if everyone signing such statements were in fact “researchers” in any reasonable sense of the term understood by scientists. However no evidence has been offered that even a majority of these signers have ever written a peer-reviewed scientific paper in their life!

      And what of Anderegg et al’s definition of “reputable” when the lists are supplied by self-declared enemies of AGW theory such as the Heartland Institute, Fred Singer, etc.?

      Anderegg et al are using a completely bogus definition of “researcher.” This is blatant dishonesty.

      • Vaughan Pratt
        Fred SInger knows far more about weather, satellites, environment and policy than most “climate scientists”. See:

        Singer was named as the first director of meteorological satellite services for the National Weather Satellite Center, now part of the National Oceanic and Atmospheric Administration, and directed a program for using satellites to forecast the weather.[15] . . .
        he became the first dean of the School of Environmental and Planetary Sciences at the University of Miami in 1964. . .
        When the U.S. Environmental Protection Agency was created on 1970, he became its deputy assistant administrator of policy.

        When Singer and other scientists report serious scientific fallacies in “catastrophic anthropogenic global warming”, I think it prudent that serious attention be given to those objections.

        I find Singer’s credential’s and expertise far more impressive than Mann’s “hockey stick”.

        I have no objection to “climate has been warming since pre-1800″,
        nor to there is “significant anthropogenic warming”.
        (NOTE “significant” = measurable).

        However, to jump to “very likely (>90%) that “most” of “global warming” is anthropogenic is unscientific and “not proven”.

        I find quoting Anderegg’s “97% to 98% of climate experts” to be far more eggregious and misleading than Anderegg’s UE which he explicitly explains. The “experts” are the most published which has the underlying funding and gatekeeping bias.

        Judith Curry’s focus on uncertainty is far more important. e.g. she is showing that the reported uncertainty in the next AR5 may actually be substantially higher than in AR4. See especially slide 39 of 51.

        Are you fighting to restore the integrity of “climate science” or for other reasons? If so, “test all things”, “kick the tires”.
        e.g. why does solar cooling cause the earth to warm? see
        Note Solar Influences on Climate Joanna Haigh –
        An influence of solar spectral variations on radiative forcing of climate
        Joanna D. Haigh1, Ann R. Winning1, Ralf Toumi1 & Jerald W. Harder, Nature Vol 467, 7 Oct. 2010 pp 696-699
        See especially Table 1

        When surprises like that pop up, we are no where close to 90%.

      • Fred Singer knows far more about weather, satellites, environment and policy than most “climate scientists”

        Not the sort of support one would expect to see coming from an alarmist. ;)

        Alarmists have this bee in their bonnet that CO2 is harmful and hence readily fall victim to confirmation bias, judging these inferior climate scientists you speak of to speak with authority and Fred Singer not because Singer’s views don’t agree with theirs.

        You see their judgment as mistaken. But this works both ways.

        The “experts” are the most published which has the underlying funding and gatekeeping bias.

        Some fear the military-industrial complex, some the government complex, some the science complex. I fear the conspiracy-theory complex.

      • So you don’t think Big Oil is conspiring against the cAGW believers?

      • The weak conspire to increase their strength. The idea that Big Oil needs to conspire is laughable.

  26. Judith: On the slide “IPCC characterization of Uncertainty”, I’d like to suggest you consider putting the traditional scientific standard of “statistically significant” (95% probability)* somewhere on the slide and be forced to discuss the reasons why alternative standards should be used in what is supposed to be a scientific report. Why is it important for scientists to warn governments of things that are merely “likely”? Is this being misused? I’d find your views on this subject very interesting.

    *Or you could include a number of scientific standards: 5 sigma for new particles in physics, two independent clinical trials showing efficacy with >95% confidence for FDA approval of new drugs to treat non-life-threatening conditions.

    (Thank you for providing a forum where such questions can be asked.)

    • Strongly support this. The IPCC’s “Very likely” (90% probability) would not be acceptable in economic research, so we should we base massive changes to economic policy on it?.

      • oops – “… so why should we base …”

      • Who or what gives climate scientists the right to advise governments using non-traditional standards and terminology such as “likely”, when other scientists hold themselves to higher standards? Readers of IPCC reports certainly don’t need a PhD to get a better understanding the meaning of “likely” when it is replaced with “at least 2/3 chance”. Does this situation have anything to do with the fact that one of the authors of these standards has advocated telling the public scary stories about climate change?

      • In statistics, the most likely value is the mode.

      • Heh, unless the mode’s been cynically manipulated with bayesian prior nonsense. Note the mode of 1K sensitivity settling around observations.
        ===========

      • Strongly support this. The IPCC’s “Very likely” (90% probability) would not be acceptable in economic research, so we should we base massive changes to economic policy on it?.

        I’m not an economist, so if you are then I defer to your judgment on this.

        If you’re not then what’s your basis for claiming that “very likely” is unacceptable? As an amateur economist myself it doesn’t sound like sound economics to me.

      • In economics, an r2 of 99% is regarded as fairly compelling, 95% is regarded as supporting the tested relationship, less than that would not be considered significant. A research paper would not argue a case on the basis of an r2 of .90.

      • Sounds like we’re in excellent agreement numerically, those r2 numbers are pretty much the thresholds I tend to judge things by. This is why I prefer my r2 = 99.5% cyclic model of global temperature to Girma’s r2 = 84.5% linear model.

        But r2 measures goodness of fit of a model to data as the proportion of variance explained, whereas probability measures something different, such as fraction of a sample space, or relative frequency, or the product of a prior with likelihood, Are you claiming that the IPCC’s “very likely” must have been based on a fit of r2 significantly less than 99%?

        I could well imagine not wanting to claim anything stronger than “very likely” on the basis of a 99% r2 fit I’d obtained. It can easily happen that two researchers have completely different explanations of the same data, both with r2 = 99%, yet totally incompatible in the sense that the two explanations make wildly different projections of future data. You can’t infer that both are very likely, at least one of them has to have a probability at best 50%, otherwise the probabilities sum to more than 1.

        Just trying to understand how economists view these sorts of things.

        Come to think of it, it would be interesting to know whether economists believe they make more reliable predictions than climate scientists, and vice versa; do climate scientists believe they make more reliable predictions than economists?

      • At a very early phase of the net one Finnish economist put on-line a collection of economist jokes now available here . One of them reads

        Q:Why did God create economists ?
        A:In order to make weather forecasters look good.

        A high value of r2 tells that the fit explains a very large fraction of the variation, but that’s only one guideline in deciding, whether the explanation has strong support. A low r2 may be enough, when there’s sufficient other knowledge to tell that the unexplained part does not invalidate the conclusion. That may happen, when the strength of random noise is large and known to be white noise. That’s of course not true for the global average surface temperature time series, but even so one shouldn’t put too much value to a single number like r2, when anything else is being asked than the share of total variability that’s explained.

        As an example a trend is not at all the same thing as total variability, when short term variability is strong. If there are strong reasons to believe that all noise is short term and everything longer term is linear, a low r2 may allow for strong evidence for the trend to exist. The real question on temperature time series is the strength of the arguments that unknown long term variability is weak.

      • A low r2 may be enough, when there’s sufficient other knowledge to tell that the unexplained part does not invalidate the conclusion. That may happen, when the strength of random noise is large and known to be white noise.

        Granted, but merely justifying a low r2 on such grounds opens the door to fallacious reasoning.

        To avoid that pitfall one should explicitly separate the noise from the signal, give the method by which the separation was performed, exhibit both, argue why neglecting the noise is unlikely to invalidate the conclusion, and give a high r2 model for the signal.

      • That may happen, when the strength of random noise is large and known to be white noise.

        “Assumed” might be preferable to “known” in such contexts. Quantum mechanics is the only physical theory based on pure probability. Elsewhere, one man’s noise is another’s signal. Signals such as short-term climate are better understood as irrelevant than as pure noise, in the sense that short-term climate is irrelevant to long-term climate.

      • Signals such as short-term climate are better understood as irrelevant than as pure noise, in the sense that short-term climate is irrelevant to long-term climate.

        I agree but the way the skeptics cast it, the excursions in short-term climate observation have some effect on inferring the mean values, which then influences the long-term trends.
        I don’t see this myself and can’t imagine it permanently suppressing the long-term trend.

      • I agree but the way the skeptics cast it, the excursions in short-term climate observation have some effect on inferring the mean values, which then influences the long-term trends.

        And why not? It’s one of the few things skeptics have to go on that makes any logical sense. You have to cut them some slack.

        Not that I’ve ever seen an actual example of such a thing…

    • Why is it important for scientists to warn governments of things that are merely “likely”?

      Why is it important for the passenger to warn the driver that it is merely “likely” that they’re about to drive off the edge of the cliff?

      • Why should the driver listen to a passenger urging him to swing left and over the economic cliff rather than swing right to a warmer and more prosperous destination?
        =========

      • Well said, Kim. If we apply the precautionary principle according to the alarmists, we’re stupid for not buying as many lottery tickets as our paychecks will permit. After all, we might win, right?

      • swing right to a warmer and more prosperous destination?

        “Swing right, sweet chariot.” This could be the winning entry for next year’s Republican chant. Four-part harmony would be a pleasant change from the “drill, baby, drill” chant.

      • Marching through the vineyards of the purple grapes of wrath.
        ================

  27. Judith: On the slide entitled “NCAR climate model simulations for the IPCC”, you have lines at the bottom for AR4 and AR5. A third line could be added: “Missing: Model parameters tuned to pre-industrial, with uncertainty in forcings. The red band of uncertainty in the AR4 line is presumably only due to chaotic nature of climate simulations, not forcing uncertainty.

    In light of Stainforth’s work, fourth line could also be added for forcing uncertainty and parameter uncertainty. This would illustrate the full scope of the uncertainty monster.

  28. Dr Curry

    You might want to check out Ross McKitrick’ website. He gave a talk today to the Third Age Learning Society. The last slide has a very familiar figure on it!
    At quick glance some of his slides have a somewhat different emphasis to yours!

    Good luck with the talk!

  29. The second last slide: “ENJOY UNCERTAINTY”.
    Great summation of what is at issue and how to proceed.
    Enjoy the process. Have fun.

  30. Judith

    Just read through the presentation. Good luck. Sounds interesting. Look forward to your report as to how it was received.

    tonyb

  31. Judith,
    In this context, I find the the use of the term — merchants of doubt — objectionable (slide 3) unless enclosed in quotation marks. The label is used as a flail to inflict damage on those who raise and publicize doubts about things that are, by their nature, questionable and to make those raising questions appear to be part of a group that is profiting from the uncertainty. To me it is akin to calling the autocratically inclined ‘Nazis’

    Perhaps you could temper the term with a ‘so-called merchants of doubt’ or something.

    I believe the term refers to a mythical bug-a-bear, called up to defend the indefensible.

    • I find the the use of the term — merchants of doubt — objectionable (slide 3) unless enclosed in quotation marks.

      This is a fair point. Doubters should always be allowed the benefit of the doubt until their doubts have been shown unreasonable.

      This principle was exploited by IBM to the point of abuse in the early 1970s when they ran into stiff competition from their former employee Gene Amdahl whose innovations they had previously rejected, forcing him to form his own company in order to realize them. Even before Amdahl left IBM, the company doubted the ultimate efficacy of Amdahl’s ideas, and felt perfectly justified in conveying those doubts to their customers so they wouldn’t jump ship, to the extent of seeing no problem making a slogan out of FUD for Fear, Uncertainty, and Doubt.

      In this way they unwittingly became early “merchants of doubt,” and would themselves have insisted on enclosing the phrase in quotation marks had they been offered the opportunity by the outside world, who preferred instead to mock them for their unwavering belief in the correctness of their perception of the inferiority of Amdahl’s computers.

  32. Other than that, I think your presentation is marvelous and important. Break a leg!

  33. A very insightful presentation but why no mention of the IAC Review which was pivotal in drawing attention to the IPCC’s poor handling of uncertainty?

  34. Incidentally, one of your slides shows that the computer model used for AR5 performs worse (compared to observations) than its predecessor. That’s progress I guess.

  35. Judith, nice job. It is clear and understandable. I like the flow.
    If the audience lights the “torch” we will arrange a Florida summer rainstorm to quench the fire.

  36. Looks good to me.

    I mean, it looks really good.

    The range of estimates for climate sensitivity is 2K – 4.5K, or about 1% +/- 0.5% of the global mean temperature.

    BUT

    most estimates are based on simplified climate models (“applied mathematics”, equilibrium in a system obviously not equilibrated [night-time and daytime temps not the same, pole and equator temps not the same]), where the error of the approximation (or inherent inaccuracy) has never been shown to be less than 3%. So the whole range of nearly agreed-upon climate sensitivities is less than the approximation error of the models. That’s before accounting for estimation random variability in the parameters.

    The uncertainty about clouds (another example of non-equilibrium) alone swamps the range of climate sensitivity estimates, and makes even the sign of the sensitivity unknown.

    Best policy options? Investments that pay off even if CO2-induced global warming should turn out to be negligible, such as flood control and irrigation projects (Eastern Australia, Indus Valley, California Central Valley). I think those were covered in one of your bullets, but some specific examples may help.

    I liked your highlighting of skeptics who are highly technically trained and who demand more accountability in the process and accountability of the scientists participating in the policy formulations.

    • BUT

      What is your basis for the claims that follow? Do you have expertise in climate modelling? Would you like to share a publication list?

      I really liked that “six questions to assess expertise” thing, but wanna be experts seem not to be inclined to enter into a dialogue about their credentials.

      Best policy options? Investments that pay off even if CO2-induced global warming should turn out to be negligible,

      Hardly. If there is, say, a loaded gun pointed at you, with a fifty-fifty chance that the person aiming it at you will hit you with there first volley, it does not therefore follow that the best option is the one that will “pay off” if the gun turns out not to be loaded.

      The best policy options are those that minimize harm if global warming turns out to be more severe than we expect.

      • Robert,
        Thanks as always for the amazing view of the believer mentality.
        You know nothing about guns, risk, or, frankly reality.
        IOW, you are the Baghdad Bob of cliamte.

      • “….wanna be experts seem not to be inclined to enter into a dialogue about their credentials.”

        Ha…Sound familiar Robert?… You couldn’t have described yourself any better.

        Like shooting fish in a barrel.

      • Robert: What is your basis for the claims that follow? Do you have expertise in climate modelling? Would you like to share a publication list?

        Nearly all of the publications that derive mathematical expressions include a description of assumptions. The derivation of the Clausius-Clapeyron equation assumes that the atmosphere is horizontally well-mixed, and input is steady-state; the result is a thermodynamic limit. But the diurnal cycle provides oscillating input, and the cloud formations are evidence against the well-mixed assumption.

        A good recent text book is “Principles of Planetary Climate” by Raymond T. Pierrehumbert. If you buy the book you can download lots of software that is helpful for doing the problems. You do not have to have expertise in climate modeling to appreciate that (a) all the derivations are based on simplifying assumptions and (b) most of the results have errors in the range of 3% – 10%. These error sizes are small compared to the error sizes that are permitted in laboratory tests for blood constituents, so I am not criticizing the scientists, but they are large compared to the quantities necessary for planning.

        If you think that AGW is analogous to a loaded pistol, then I think you are missing the point of the Uncertainty Monster altogether.

    • Harold H Doiron

      MattStat,

      Excellent points!! Let me add some supporting and “pet peeve” comments.

      With regard to your last paragraph above, I think I am one of those “highly technically trained” “skeptics” from the Mechanical Engineering field demanding more accountability. I appreciate the fact that Dr. Curry has the wisdom and courage to think that our group of critics might have something to offer to the fledgling field of predictive climate science.

      I also think my experience and wisdom from 48 years of practice where results of my modeling of complex dynamic phenomena such as the toppling dynamics of the Apollo Lunar Module, Skylab spacecraft docking dynamics, and stability analysis of Space Shuttle rocket engine thrust oscillations resulting from Shuttle structural vibrations exciting pressure and flow oscillations in liquid propellant feedlines, that had life or death consequences for astronauts, earns me the right to be called a “Climate Change Realist” rather than “skeptic”.

      Based on what we confidently know about root cause of the earth’s very stable global average temperature variations of the last 10,000 years, including even smaller temperature variations of the last 200 years, is it “realistic” or “skeptical” to believe that those who propose to limit CO2 emissions to control the global average temperature of the earth for the future, don’t have much of a chance of being proved correct for the long term? I think I have something to offer the general fields of science regarding modeling, observing and detecting the stability characteristics of complex dynamic systems.

      Let’s try to put a quantitative number on certainty of expected outcomes even if we could limit CO2 emissions from all countries. I suggest that long term available empirical data regarding cause/effect relationships of CO2 concentrations in the atmosphere and global average temperatures, as well as doubts about unvalidated computer model predictions, gives CO2 control much less than a 10% chance of achieving the desired result. So why would we spend $trillions NOW to try to limit global CO2 emissions, even when other rapidly growing industrialized countries like China and India have made it clear they have no intention of doing so. Is this a proposed solution that has a good chance of working? Please, AGW consensus climate change scientists, tell my why this solution is what you advise to our public policy leaders.

      Based on the flimsy basis for your recommendation with potentially severe adverse consequences, you would be booed off the stage in the NASA critical decision-making processes that I have endured, when trying to convince decision makers on the basis of my complex models (that were validated by experiments), what we need to do for safety of our astronauts.

      Who is being realistic here? From a practical point of view (also known as an engineering point of view), wouldn’t available resources be better spent trying to adapt to an uncertain, but potential earth warming problem, rather than putting all of our eggs in the basket of trying to control CO2 emissions? Given that feeding the planet’s growing population is a more pressing, urgent problem, wouldn’t more CO2 in the atmosphere providing higher crop yields (with high and quantifiable certainty previously validated by experiments) be a factor in deciding what to do about global warming concerns?

      What about the warming trends of the last decade? Has warming maxed out and perhaps we might be entering another cooling phase as has happened time and time again in the earth’s recent 10,000 years of very stable climate variations? Do climate change model predictions from a decade ago, give us any confidence that we should believe their predictions NOW for the next 50 or 100 years into the future? Where is the empirical evidence that these models can accurately predict anything of significance that justifies drastic changes in public policy? Why are climate change theories exempt from long established scientific methods requiring empirical verification on the same time scales as their predictions? Why shouldn’t highly trained technical experts from other fields be treated with more respect for insisting that climate scientists follow all the broadly accepted rules of the scientific method, self-imposed by good science in other technical fields of study?

      I would prefer to be called a “Climate Change Realist”. When Climate Change scientists have earned their spurs by accurately predicting climate change trends for the next several decades, they can begin to earn the right to call me a “skeptic”. Their track record from the last 50 years is dismal, so why should they be the “realists” and me, the “skeptic”. What notable achievement gives them the upper hand on credibility?

      Kudos, Dr. Curry for trying to convince your colleagues that climate scientists need to get more realistic and pay more attention to the Uncertainty Monster that we in other fields give great respect, especially when public safety and well being are concerned. I hope you are prepared to answer these questions from some crusty old scientists and engineers from other fields at MIT.

      • Harold H. Doiron: Do climate change model predictions from a decade ago, give us any confidence that we should believe their predictions NOW for the next 50 or 100 years into the future?

        I wrote an answer to that below, before I read your post.

      • So why would we spend $trillions NOW to try to limit global CO2 emissions, even when other rapidly growing industrialized countries like China and India have made it clear they have no intention of doing so?

        Harold, you could have saved valuable time simply by saying Argument 40 at sceptical science. You’ve added nothing new to well-known arguments of climate skeptics.

        Maybe those arguments are right, maybe they’re wrong, but repeating them ad nauseam isn’t going to make them any more right or wrong. It’s boring listening to them over and over. Just use the number 40 next time.

      • As the foremost problem in climatology is the inability to reduce the range of uncertainty in climate sensitivity over the last 3-4 decades.The research in both the fast and slow modes ( metrological and climate) seem to have reached the constraints and limits of the underlying hypothesis ie the irreducibility limit.

        Hence it is legitimate to pose the problem, is the inability to reduce uncertainty in sensitivity evidence of the certainty of irreducibility?.

        Now one could say examine the arguments detailed at SS ,and formulate legitimate problems in say solar, or internal variability such as enso by random dynamical theory, and random attractors etc ie limit cycles.This approach would reduce the uncertainty to binary problems ie what is predictable and what is not.

        Then again as time is valuable as you suggest, and If one takes the conservative view on the solution of this problem,then the answer is simple and well proven ie there is no solution.

        http://www.scholarpedia.org/article/Matiyasevich_theorem

  37. Will it be webcast?
    Or a video posted?

  38. MattStat – We have a good idea what was and was not operating from 1950-2007, so we don’t have to guess the relationship to previous eras. We have information on CO2, methane, black carbon, solar changes, and natural fluctuations for the interval, and in combination these lead to the conclusion that most warming was due to the ghgs. Based on the quantitations I’ve seen, “most” in this case probably exceeds 50 percent by a safe margin.

    As to the 1910-1940 interval, there is good evidence that the warming represented a combination of solar and GHG forcing, with possibly a contribution from changes in volcanic activity. The net effect of natural fluctuations may also have been greater based on the AMO and PDO data, but whether this was a significant contributor is hard to determine

    There are some common factors, and some dissimilar ones between the two intervals, but 1950-2007 can be judged on the basis of what was then happening. The conclusion is quite robust, but must always be qualified by the possibility of something unknown. That is why it’s not 100 percent certain, but instead “very likely”. I think it’s somewhat disappointing that this interval is used to illustrate the notion that the strength of scientific consensus exceeds the strength of the evidence. In this case, the evidence is quite strong, but there are other conclusions drawn by the IPCC or other groups where the uncertainty is greater, and which would illustrate more convincingly the need to avoid overconfidence.

    • Fred Moolton: The conclusion is quite robust, but must always be qualified by the possibility of something unknown.

      I objected to your exact wording: completely unsuspected and unmeasured phenomenon, to refer to stuff that is widely suspected and partially measured. For example, it is widely (not universally) suspected that the effects of clouds will be to cool the atmosphere, and the effects of clouds are partially measured (with some results supporting the idea of cooling.) Equally, it is widely (not universally) suspected that the natural background process contains a linear component and a cyclical component, and that these are partially measured by the climate record from 1850 through about 1950.

      I think that you are way overconfident, and that the conclusion your refer to is not robust because of model inaccuracies and parameter imprecision.

      Consider Clausius-Clapayron again: you can witness its inadequacy by watching the clouds accumulate nearly every sunny day in Central Missouri, Taiwan, The Philippines and many other locations. It’s probably only off by a few % at each level for most of the ground, but by much more in the column containing an afternoon thunder cloud, and even more in the following rain. Is this enough inaccuracy to call into question the IPCC confidence in the interval 2K – 4.5K for the climate sensitivity, given today’s climate? Sure. Any derivation assuming C-C is “written in water”, so to speak.

      • MattStat and Fred Moolten

        Here is another reason why the 2007 IPCC AR4 WG1 SPM claim was suspect at the time and can now be seriously questioned, i.e.

        Most of the observed increase in global average temperatures since the mid-20th century is very likely due to the observed increase in anthropogenic greenhouse gas concentrations.

        http://www.sciencebits.com/CLOUDresults

        The new results just published in nature by Kirkby and company are the results of the CLOUD experiment. This experiment mimics the conditions found in the atmosphere (i.e., air, water vapor, and trace gasses, such as sulfuric acid and ammonia). It is a repeat of the Danish SKY experiment carried out by Henrik Svensmark and his colleagues, and it produces the same results—namely, they show that an increase in the rate of atmospheric ionization increases the formation rate of condensation nuclei. The only difference is that the CLOUD experiment with its considerably higher budget, has a better control on the different setup parameters. Moreover, those parameters can be measured over a wider range. This allows the CLOUD experiment to more vividly see the effect.

        The results unequivocally demonstrate that atmospheric ionization can very easily affect the formation of condensation nuclei (CNs). Since many regions of earth are devoid of natural sources for [cloud condensation nuclei] CCNs (e.g., dust), the CCNs have to grow from the smaller CNs, hence, the CCN density will naturally be affected by the ionization, and therefore, the cosmic ray flux. This implies that ion induced nucleation is the most natural explanation linking between observed cosmic ray flux variations and climate. It has both empirical and beautify experimental results to support it.

        Second, given that the cosmic ray flux climate link can naturally be explained, the often heard “no proven mechanism and therefore it should be dismissed” argument should be tucked safely away. In fact, given the laboratory evidence, it should have been considered strange if there were no empirical CRF/climate links!

        Last, given that the CRF/climate link is alive and kicking, it naturally explains the large solar/climate links. As a consequence, anyone trying to understand past (and future) climate change must consider the whole effect that the sun has on climate, not just the relatively small variations in the total irradiance (which is the only solar influence most modelers consider). This in turn implies (and I will write about it in the near future), that some of the 20th century warming should be attributed to the sun, and that the climate sensitivity is on the low side (around 1 deg increase per CO2 doubling).

        Max

      • The effect is probably real but almost certainly trivial. After looking at the specific data, I think we can say with high but not absolute confidence that most warming between 1950 and 2007 was caused by anthropogenic GHGs. However, what I think or you think is less relevant than what Dr. Curry’s audience will think. If they include climate scientists – a group she might particularly want to persuade – we already know they are likely to agree with the AR4 attribution for 1950-2007 because they see the evidence as strong. If she wishes to convince listeners that overconfidence is a danger, using this example will probably prove counterproductive for this particular group, who are likely to think “well, if that’s the best example of overconfidence available, there’s nothing to worry about”. There are other examples that I believe would make the point in favor of her perspective rather than in opposition to it.

      • Maybe, but needs much more evidence. There’s a good essay over at Real Climate right now.

    • Something is wrong here. Aerosol forcings are significant and have an error bar of 100%. Cloud feedbacks likewise in dispute. If the modela are wrong on these things, then you can’t use the “we included everthing else but agg”. The NCAR model results in Judith’s material shows that these unknowns can have a big impact on the models. Inany case, the numerical methods used in models are the best ones from the 1960’s (such as explicit time marching) and the modelers cannot point me to any sensitivity studies with to the parameters. Not a situation that inspires confidence in the models. Further, the math basis idls weak. It goes as follows: We integrate in time a system that is chaotic at a high level in time and then claim that the long term patterns and averages mean sonething. The evidence fot this is based purely on running the models. In any case, i would not assign a 90% probability to anything based on the models.

      • “Aerosol forcings are significant and have an error bar of 100%. Cloud feedbacks likewise in dispute”.

        David – Despite their uncertaintiies, neither aerosol forcings of the type you refer to, nor cloud feedbacks have much impact on the validity of the assertion that most 1950-2007 warming was due to anthropogenic greenhouse gases. That assertion is well supported by evidence that is more relevant, as suggested in earlier comments.

        Much data reported by Martin Wild and others indicate that the interval was characterized by an increase followed by a smaller decline in cooling aerosols, with a net slight cooling effect at the end. Because the aerosols didn’t warm, the magnitude of their effect is irrelevant to any apportionment of warming, which must be divided up among causes of warming. (The above refers to sulfate and other industrial cooling aerosols. Some aerosols contain black carbon, which Ramanathan and others have shown to have warming effects, but with a forcing level much below that of GHGs when averaged globally).

        A similar principle applies to cloud feedback. This is relevant to climate sensitivity estimates, which tell us the extent to which forcings are amplified or diminished. However, the apportionment of most warming to ghgs as opposed to other forcings is unaffected (or minimally affected) by climate sensitivity values that appear to apply to all competing long term forcings, and would therefore not change the proportions. Elsewhere, I’ve commented on the curves showing that the known sources of unforced variability account for very small net effects over the 1950-2007 interval, although it would be more significant for other intervals.

        All the above reinforces a point I tried to make in responding to your comments in the subsequent thread about problems with numerical solutions in GCMs. You had an informative exchange with Gavin at RC, and I suggested that we would all do better if you continued to engage with him or other GCM modelers rather than simply post criticisms here, where modelers are unlikely to respond. I was not convinced by your reasons for rejecting that suggestion, and I believe you should reconsider. I don’t know whether your criticisms are particularly important nor whether you are right in suggesting that the modelers have neglected them. However, you have expertise in fluid dynamics and relevant mathematics from which they and we might learn something if further dialog occurs. Similarly, you would be able to learn from them about the significance of your concerns as they apply to actual climate change. I state this based on your above comment, which indicates that climate change is an area where you are much less well informed than in your own area of expertise.

      • Fred,
        I beg to differ on the aerosols. The IPCC shows the range to be large for the forcing as Judith points out. Just measuring them is not enough, we need to know the effect of clouds, etc.

        You refer to the “known sources of unforced variability” being very small. How do we know clouds are “unforced.” How do we account for the midevel warm period or the little ice age?

        On the models, I wish I had the energy to do another RC conversation. Some of my comments on that site have been moderated out without explanation and that does not give me confidence. Basically, criticism of the team, not matter how civil, is not permitted on RC and that tells me I may well get dogma there instead of science. I have enough trouble overturning clearly wrong doctrine in my own field which is less political.

      • David – I believe you’re making my point for me. If you look at the actual data for the relevant interval (1950-2007), the magnitude of aerosol forcing turns out to be irrelevant (including indirect effects on clouds). The reason is that during this interval, aerosols were not a warming influence but a slight cooling influence This is based on observational data, although given the uncertainties, one could argue the influence might have been greater than slight. Since they didn’t warm, they don’t affect the apportionment of warming among greenhouse gases, solar forcing, and black carbon, where the greenhouse gases appear clearly to exert the dominant forcing..

        We have reasonably good cloud data indicating that clouds are very responsive to climate forcings, but neither any data nor any physical mechanism consistent with the laws of thermodynamics applied to climate to suggest that they can independently exert long term forcings themselves. I suppose that remote possibility could be considered one reason why the IPCC attribution statement used the term “very likely” rather than “absolutely certain” in assigning most warming to the greenhouse gases, but that is about the best one can say for a hypothetical phenomenon with no empirical or theoretical support.

        I don’t see the relevance of the MWP or Little Ice Age. Why did you bring them up? Do you think that climate science is unaware that climate change can involve natural phenomena? We have data suggestive of mechanisms involving solar changes, volcanism, and regional alterations in atmospheric and ocean circulation patterns, particularly affecting the North Atlantic region, but so what? What does this tell us about why the climate warmed between 1950 and 2007? The fact that you introduce this irrelevancy tells me that you have some misconceptions about factors determining global temperature anomalies, which are known to reflect a variety of anthropogenic and natural processes – the question is which processes were operating during an interval of interest. This is why I think it would be a mutual learning experience for you to discuss numerical errors with the modelers and for them (and perhaps some of the rest of us) to discuss climate dynamics with you, including observational data during 1950-2007.

        Finally, I looked at the Paul Williams article on time-stepping. It’s very interesting, How much of a difference would be made by his suggested improvements is something I’m unqualified to judge. However, the modelers may already know about this and have some ideas, and if they don’t, that’s another reason for you to engage with them, to your mutual benefit.

      • Also remember that in addition to RC, I recommended that you visit Isaac Held’s blog, where I don’t think you’ll find the same degree of polemicism.

    • As to the 1910-1940 interval, there is good evidence that the warming represented a combination of solar and GHG forcing, with possibly a contribution from changes in volcanic activity.

      The old wives tale that the moon is made of moon rocks is refuted by good evidence that it is made of green cheese. Not that I actually have this “good evidence,” how about you? And are we working with the same standards of “good”?

    • As to the 1910-1940 interval, there is good evidence that the warming represented a combination of solar and GHG forcing, with possibly a contribution from changes in volcanic activity. The net effect of natural fluctuations may also have been greater based on the AMO and PDO data, but whether this was a significant contributor is hard to determine.

      I may be able to answer that. I would break down the rise from 1910 to 1940 as follows.

      Solar forcing 0%
      GHG forcing 30%
      Volcanic activity 0%
      AMO+PDO 70%

      I may be off slightly with the solar forcing, but not too much.

      • AMO+PDO 70%

        Ghosts in the machine, eg M. Vincze and I. M. J´anosi 2011

        In this work we critically compare the consequences of two assumptions on the physical nature of the AMO index signal. First, we show that the widely used approach based on red noise statistics cannot fully reproduce the empirical correlation properties of the record. Second, we consider a process of long range power-law correlations and demonstrate its better fit to the AMO signal. We show that in the latter case, the multidecadal oscillatory mode of
        the smoothed AMO index with an assigned period length of 50–70 years can be a simple statistical artifact, a consequence of limited record length. In this respect, a better term to describe the observed fluctuations of a smooth power-law spectrum is Atlantic Multidecadal Variability (AMV).

        http://www.nonlin-processes-geophys.net/18/469/2011/

        As the authors state the title is based on the work of Godfrey 2002 and it is indeed a remarkable paper eg.

        It is a recognized characteristic of human psychology that people will find patterns in the world around them, whether or not those patterns
        result from coherent underlying causes. “The tendency to impute order to ambiguous stimuli is simply built into the cognitive machinery we use to apprehend the world. It may have been bred into us through evolution because of its general adaptiveness . . .” (Gilovich 1993,Ch. 2). While this powerful human capacity to find order in nature has served and continues to
        serve us extremely well, it also sometimes leads us to falsely impute meaning to chance events. Gilovich nicely illustrates this problem using the
        statistics of consecutive hit or missed shots in basketball (the “hot hand”), where statistical independence can reasonably be assumed. When
        dealing with the non-independent statistics of the atmosphere, the problem of “detecting” spurious patterns is amplified by the statistical relatedness
        of data that are nearby in time or space or both (see Livezey and Chen (1983), for a good example), and here our instinctive tendency to read
        too much into apparent patterns must be guarded against especially strongly. In the case of the January thaw, what superficially appear to be coherent singularities in the observed data can be adequately explained as products of time dependence, spatial dependence, and chance weather occurrences.

        ….This is the same conclusion reached long ago by Marvin (1919), who
        wrote that “each striking feature on a long record is, therefore, no evidence of the persistent recurrence of peculiar irregularities, but is simply the
        residual scar or imprint of some unusual event, or a few which have been fortuitously combined at about the time in question.”

      • interesting paper, thanks for the link

      • Gilovich nicely illustrates this problem using the
        statistics of consecutive hit or missed shots in basketball (the “hot hand”), where statistical independence can reasonably be assumed.

        As a sports fan, this is a topic of interest to me. It is fascinating how in baseball, in particular, so many assumptions are made about players or teams being hot or cold “right now,” – when more than likely, the most recent performance is not predictive of what will happen next, certainly as compared to season stats or lifetime stats. If you watch one of the playoff games, you will hear this type pattern-finding in the sportscasting constantly.

        That said, the studies of basketball players being more likely to make a shot if they are “in the zone,” are not all that well controlled for potentially influential variables – such as game conditions.

        Also – I’m not sure how this applies to climate science per se, but statisticians will tell you that in aggregate, for example, there is no validity to the notion that players hit any better or worse in “high leverage” situations, such as with runners in scoring position – but, there are individual players who defy the results of aggregated statistics. For example, Ryan Howard has hit better with runners in scoring position throughout his career than in other conditions; the reason being that defense shift their positioning when defending him depending on whether runners are on base or not. The point there is that it’s all about how analysis is always dependent on the assumed conditions, and assumed conditions (almost) always are influence by confirmation bias and motivated reasoning.

      • Shezz, Dr. Pratt you are way off! Solar forcing was at least 5% :) I would change the GHG to anthropogenic forcing, I still think that land use and black carbon played larger roles.

      • Dallas – I assume “at least 5%” is intended humorously, but since I have no sense of humor, I can’t be sure. Early twentieth century warming appears to have experienced a major contribution from solar forcing. Volcanic changes should probably not be assigned a value of zero, either. I don’t have the data at hand, but I’ve seen reports that reduced volcanism contributed to the warming as well during that era.

      • Fred, you have to have a sense of humor, you’re a Libra :) A paper by Moberg I think, had a good bit of information on 1910-1940. It had a positive forcing for aerosols for roughly 1935 to 1938, so volcanic was very low and evidently black carbon fairly high. It also used the older TSI reconstructions, well after newer paper by the same authors had be published as we have discussed before. The paper you linked looks interesting, I only skimmed it, but noticed uncertainty in mechanisms which is a large issue and the nonuniform impacts which have been one of my largest concerns with the whole disappearing MWP issue. I will try to read it later.

      • Solar forcing was at least 5%

        Thanks, Dallas. I’m not sure what I was thinking when I put 0% there. I should have a shot at estimating it.

        Volcanic changes should probably not be assigned a value of zero, either. I don’t have the data at hand, but I’ve seen reports that reduced volcanism contributed to the warming as well during that era.

        That would be for the period 1930-1940, and I agree I was too fast in assigning that period 0%. On the basis of my modeling it looks like 10% would be a fair assignment for reduced volcanism during 1930-1940.

        For 1910-1930 we have the following six major volcanoes, which between them would appear to indicate 0% as a fair estimate of the contribution of reduced volcanism.. (Decimals in the year estimate the month of the year.)

        Taal, 1911.5
        Mt Katmai, 1912.4
        Kelut, 1919.5
        Santa Maria, 1922.15
        Etna, 1928.85
        Vesuvius, 1929.4

        In this respect, a better term to describe the observed fluctuations of a smooth power-law spectrum is Atlantic Multidecadal Variability (AMV).

        Fine by me. I didn’t make up the name AMO, I just use what I’m handed.

        Here’s my revised version.

        Solar forcing 5% (Dallas, pending refinement)
        Anthropogenic forcing 27% (Good catch, that’s what I meant)
        Volcanic activity 3% (3x dilution of 10%)
        AMV 65% (or whatever you want to call those fluctuations)

      • “Volcanic activity” should be “reduced volcanism”

      • Dr. Pratt,

        Thanks for the simplified F/T equation, but now I am in the running for the new Oliver Manuel award :)

  39. Hi Judith
    Looks like a formatting error in the first bullet point of the last page.

  40. Alexander Harvey

    Judith,

    It troubles me that some parts of your presentation are either necessary or untested. Here but mostly elsewhere in other written argument you have given your inference, from what is known, to the likely IPCC AR4 WGI Ch 9 decision process. Your view on how they may have come to a specific judgement onthe attribution.

    Is their process reallly that opaque? It may not be well documented but is it not possible to contact a few key players and ask? Surely somebody must know.

    Perhaps M Goldstein’s (earlier comment, other thread) sharpest point addressed transparency. Given transparency as to method, it would be quite acceptable (but not very useful) if it was but no more than the rolling of a die.

    Without transparency there is no access to traceability. If we can each infer what we like as to the method used, we can make our own assessment as to which data (including solicitted opinion) the judgement relies on.

    You can say the judgement relies over heavily on the modelling, I could disagree. This is an issue that is hopefully decidable. If I knew for certain, absolutely categorically, as to the method, I would know precisely what I have inferred that is not so, and so you would too.

    So I must ask you, is it valid for me to suggest that? Is the process so opaque that we could fairly infer quite different characterisations to it?

    I should like to be wrong, can you assure me that you know what their method truly is, or if not, ask them.

    I think this is crucial. If I knew for certain the method used I could attempt to attribute some weighting scheme and answer such questions as:

    What data/information has been totally ignored (zero weighted)?
    What data/information has be over utilised (counted more than once)?

    Both of these questions are argued over, both here and elsewhere, given transparency they would be decidable as opposed to debatable.

    Perhaps If I have got this all horribly wrong, but if not, the publication of the method, in sufficient detail that the key judgments can be reproduced would seem to be a necessary step on the road. I simply do not care if it was a show of hands provided the vote was recorded and the method of solicitation of, and weighting scheme given to, such expert opinion is available for scrutiny. I think that this was much of M Goldstein’s point. Those involved might hate it, but they might just have to get over that.

    Alex

    • My understanding of the process is that it is “negotiated” among the people in the room.

      • I was once involved (around 1968) in government-industry negotiations where import penetration of the UK car market was an important factor in determining policy. Both sides, with no particular rationale, foresaw the import share rising from about 12% to about 14% over a few years. I argued that there were indications that there would be a much more rapid rise. The figure was amended to 14.5%. In the event, import share rose to 45-50% within a few years. I think we need details of the “negotiations”.

      • One question that’s been tossed around lately in climate circles is how reliable is past performance as an indicator of future skill. There it’s applied to climate models, but it could equally well be applied to ostensibly clairvoyant young economists. Without meaning to ask about your own success there, what’s been your experience in general of whether the better economic forecasters stay that way in the long run?

        Warren Buffet comes to mind, though his M.S. in Economics from Columbia might be the extent to which he can call himself an economist.

  41. Alexander Harvey

    Judith,

    I have read through your presentation and I do appreciate it.

    I have something that I wish to communicate that may have a resonance with you. I haven’t sorted it out in my own mind so I will attempt a metaphor, something more meaningful than true. I am not going to show you anything that you don’t know but by metaphor illustrate a recurring theme.

    The Information Cake.

    All the information that went into a judgment and how it was apportioned, whether any is left on the plate or worst if any was multiply allocated.

    This bears directly on your slide CCSM3 vs CCSM4. In CCSM3 part of the cake is eaten twice (20th C data) and part left on the plate (pre-industrial), in the latter CCSM4, more of the cake is eaten but just once. The double consumption is the circular reasoning you highlight. I may differ in that I feel that this counld be quantified and the uncertainty modified accordingly.

    My second illustration may be at the heart of where we may disagree. I need to get one point out of the way first. You highlight the usge of the word most and how this renders the judgement less informative. I will tighten this by saying >50% which is more precise.

    I think you may be suggesting that they have left a lot of the cake on the plate, and failed to fully utilise it to characterise the natural variability and then overworked the remaining data and produced a statement with a good amount of information content that is not particularly robust, as in open to challenge.

    I might say that they have used up much or most of the information in the formation of the question, in designing in robustness, the particular choice of interval, “since the mid 20th century”, and the use of “most” (>50%) as opposed to all other choices >50% etc. But I can’t have it both ways, there is only so much cake, so I would suggest that it is likely robust, but is almost devoid of information. The information has gone into the robustness not the judgment itself.

    You might say that they cannot justify the information content that the statement is not robust to legitimate challenge, and that is fair.

    I might say they can fully justify the statement as it has very little redundane information content to justify. That it is not much open to challenge because it doesn’t actually have much usable content to challenge.

    I think the same statements are equivalent in terms of the utility of the judgement. I will try and say why I think this is true.

    Given that they chose how to formulate the question (and in so doing used up most of the information cake) what is the likelihood of the judgment not being robust?

    Hopefully very small.

    Given the information available, they could construct the set of all possible judgements periods, strengths (likely, very likely etc,) for the attribution and all the variants on tem “most”, and pick a question that trades off robustness, certainty (“very likely” etc.) and strength (“>xx%”). That is fine but not without consequence. There is only so much information cake and I would suggest that most all of it as eaten to ensure robustness given the stated certainty and strength leaving nothing left over for further interpretation, for its utility. The judgement is robust, and moderately strong relatively certain but otherwise content free. By that I mean that there is no redundant information that can be used up in the application of the judgement to policy or anything else.

    Our views on the division of the cake may differ that is not germane. My point is that the cake is finite and if you use some for the stated certainty of the judgement and some for ensuring the robustness of that degree of certainty and some for its strength, this diminishes the amount of further work that the judgment can perform. If one wishes to apply it to policy it must have some cake left over for that purpose. We may both agree that there is little left for policy on the plate but do so for different reasons, that matters less than how much of the cake is left over for policy. We could trade off robustness, strength, and certainty but if we fail to have any cake left over then we have a judgement that might be fair but futile.

    You may say that the judgement is outrageous and not fit for policy, I might say that it is a constructed truism, having zero utility by design.

    What we might agree is that a statement weaker in strength (than “most”), less certain (than “very likely”) or less tied to specific dates (less picked) would have eaten up less of the cake leaving more (some?) left over for its utility.

    Alex

    • Verrrrrry interesting. The intended utility is in the context of the precautionary principle, trying to come up with a confident statement that would trigger the precautionary principle. I will definitely ponder this.

      • Is there only one “precautionary principle?

        First do no harm?

        Look before you leap?

        Don’t put all your eggs in one basket?

        Don’t count your chickens before they hatch?

        Everything that can go wrong will go wrong?

      • “First do no harm.”

        That’s the principle.

      • Good point. If your driver were about to drive off the right edge of the road and fall into the valley below, you might harm his pride by pushing the steering wheel to the left.

      • Vaughan,

        Your point is no good. Pride is harm.

      • Vaughan,
        We are so far over the left lane and into the left shoulder it is not that right wing cliff you think you see that is the problem. It is the bridge abutment that is going to kill us, but you are so stuck on the left lane you are not even bothering to look.

      • (With apologies to Jim Croce)

        You don’t tug on Superman’s cape
        You don’t spit into the wind
        You don’t pull the mask off the old Lone Ranger
        And you don’t mess around with Slim…

        Yeah, Big Oil got its hat
        Find out where it’s at
        And not hustling people strange to you
        Even if you do got gubmint subsidies to make more CO2

      • Bart R,
        You should deeply profoundly apologize to Jim’s ghost.
        and the bs about subsidy to make more CO2 is typical of someone who desperately wants to avoid the political and financial scam of solar and wind energy.
        Good luck with that and do keep your day job.

      • With language like that you sound pretty desperate yourself, hunter. ;)

    • Alex

      Current cake:
      Most: >50%
      Very likely: >90%
      since the mid-20th century = 1951-2005

      New cake:
      A whole bunch: >?
      Perhaps: >?
      For a fairly long time now = ?

      A whole bunch of the observed increase in global warming for a fairly long time now is perhaps due to the observed increase in anthropogenic greenhouse gas concentrations.

      I like it!

      Max

      • PS

        Add legal disclaimer:

        “at least that’s what our models suggest; but then again our models couldn’t figure out what caused the warming in the early part of this century, so maybe they’ve got this wrong, as well.”

  42. H’mm

    51 slides – many with quite complex verbal statements in them. And given to a perhaps ‘hostile’ audience.

    3 hours minumum? With at least one pitstop. Any less than that and you will be rushing over the argument. If you have less time (and I guess you do), you need to prune out the content. Better to make the three most telling points well than skimp on all of ten good ones

    There are no brownie points for quantity over quality (despite what the Climate Scientists might try to make you believe)

    Please rehearse this in as near as the actual conditions as you can simulate …and get an uncommitted (or role-playing uncommitted) audience to watch it. And time it. You always have less time than you think.

    Good luck!

    • 3 hours minumum?

      I had a similar thought. I think it will come in under 1 hour, but there won’t be much time for thinking or for extemporaneous exposition.

      • No more than 20 slide per hour or you will be gabbling and lose half the audience is a good rule of thumb for professional presenters. And 10 per hour is likely a good target.

        Professional presenters start by an understanding of what the audeince probably knows and try to build an argument from there. Academics in general seem to take the opposite view…’sod the audience, I just want to show off how much I know’, which might be good for their egos, but does little for increased understanding.

        Judith is probably less guilty than many but she should keep in mind that she is trying to win hearts and minds by seduction, not by steam rollering. Quality beats quantity.

      • No more than 20 slide per hour or you will be gabbling and lose half the audience is a good rule of thumb for professional presenters. And 10 per hour is likely a good target.

        Agreed, roughly speaking. I generally try to organize my slides to contain roughly 2 minutes of material per slide, which for a 60-minute talk comes to 30 slides. In June I talked at ANU in Canberra on “The Logic of Global Warming: A Bitter Pill” and had exactly 30 slides which took exactly one hour. The bulk of the audience hung around for another hour, evidence that there’s a lot of interest in this topic currently, at least in the Australian counterpart of Washington DC. (I gave several talks in Sydney that month, but on various other topics since no one in Sydney had expressed any interest in my global warming talk.)

  43. Judith,

    Cannot get more uncertain than when the current models try to project into the deep past.
    Certainly would be VERY interesting to see what the models would say the climate was 4.5 billion years ago.
    This could possible be a good comedy moment of how solid equations can give fantastically wild predictions without having to be constantly adjusted.

    • I am most interested in seeing the models deal with the transitions from warming to cooling and from cooling to warming during the last major ice ages and warming periods. In particular, I want to see how they get enough energy to melt miles thick ice sheets quickly while warming the earth at the same time, going backwards on a similar temperature profile that they went forward through when they were building ice sheets.

    • Certainly would be VERY interesting to see what the models would say the climate was 4.5 billion years ago.

      It certainly would be. If we found an accurate one we could then extrapolate it forwards so as to come up with a policy applicable in 4.5 billion years time. I know some people in our philosophy department who would find that very interesting.

  44. Dear Dr Curry
    Thank you for this post and for what its worth you presentation is excellant. Also you willingness to request and accept criticism of your work is even better.
    Good luck.
    In the valley of the blind the one eyed woman is Queen :-)

  45. Since 2000, the actual course of the global annual mean temperature has diverged from the predictions made for it. There are at least 3 attitudes towards this divergence:

    1. The divergence is entirely random variation in the climate system. If that is true, then the amount of random variation in the climate system is so great that none of the parameter estimates can be precise enough to make a precise forecast for 2050.

    2. The divergence is entirely due to inaccuracies in the models. If that is true, then the inaccuracies of the model are so great that predictions for 2050 are not credible.

    3. Some of the divergence is due to random variation in the climate system, and some is due to inaccuracies in the model: 50:50, 90:10, or 10:90, or whatever you think appropriate. If that is true, then the divergence of the actual climate from the climate forecasts shows that the models are sufficiently inaccurate and the climate has enough random variability that the model forecasts for 2050 can not be considered accurate.

    No matter how you cut it, the divergences of the climate since 2000 from the forecasts made for it as of 2000 provide reason to doubt the adequacy of the models for planning for 2050.

    • You missed one Matt:

      4. da missing heat… be in da deep ocean

      • Maybe. We’ll have time to address that in more detail some other time.

      • 4. da missing heat…be in da deep ocean (mebbe) but caint fin’ it deah, an eff it is deah, it nevah come back out ennyhow, so it’s gawn (might jes as well nevah be no missing heat in da fust place).

      • “4. da missing heat…be in da deep ocean (mebbe) but caint fin’ it deah, an eff it is deah, it nevah come back out ennyhow, so it’s gawn (might jes as well nevah be no missing heat in da fust place).”

        tru dat…fashizzle

    • 3. Some of the divergence is due to random variation in the climate system, and some is due to inaccuracies in the model: 50:50, 90:10, or 10:90, or whatever you think appropriate. If that is true, then the divergence of the actual climate from the climate forecasts shows that the models are sufficiently inaccurate and the climate has enough random variability that the model forecasts for 2050 can not be considered accurate.

      If you base a projection for 40 years into the future on what happened in the past 5 years, you will almost certainly come up with rubbish. There is no shortage of 5-year periods between 1970 and now which would have forecast a decline in temperature long before now, but which did not come to pass.

      The 7-year period from 1980 to 1987, right in the middle of the steep rise over the last third of the 20th century, showed what looked at the time like a very significant 0.19 °C/decade decline. As it turned out there was nothing significant about it whatsoever, the temperature continued to climb at a high rate.

      A minimum historical window for a 40-year projection would surely be 15 years, if not much more. But if you look at every 15-year window since 1970, you will see nothing but steady rises with the exception of the occasional 1-3 months showing a barely detectable decline. The rate of such brief declines has been slowing, and the most recent one was a decade ago.

      Basing a projection 40 years in the future on a 15-year window, it would appear we’re in for a hot time. Extend the basis for the projection to a 20-year window and all doubt disappears completely. As does a 40-year window, in spades.

      • Basing a projection 40 years in the future on a 15-year window, it would appear we’re in for a hot time.

        NO!

        You stop to calculate climate trends after a shift in climate.
        http://bit.ly/emAwAu

        From the above data, here are the approximate years for shift in climate: [1880s, 1910s, 1940s, 1970s, 2000s]

        You calculate climate trends between successive climate shifts.

        Here is the start of the cooling trend since the shift in the 2000s:
        http://bit.ly/pMHO76

        Based on previous patterns, this cooling trend will continue until the 2030s.

        Here is the pattern from 1880s to 2000s: http://bit.ly/ocY95R

      • Vaughan Pratt
        Girma shows the very substantial natural cycles on a long term trend as do other researchers.

        If you carefully study Curry’s presentation slides 30, 35, 37, 38, 39, you will see that the uncertainties are far higher than commonly presented. Furthermore, the downward trends are not explicable by current models.

        See WUWT Plants gobbling up CO2 – 45% more than thought
        What confidence does that engender to find our basic understanding of the carbon cycle is so far off?

        See:
        See “Nigel Fox of the UK National Physics Laboratory observes that cloud uncertainties alone are ~ Feedback Factor Uncertainty (2 sigma) 0.24 out of 0.26 total uncertainties (~93%) in IPCC’s models. From Roe & Baker 2007. See bottom right of slide 13 of 55 in his presentation:

        Accurate radiometry from space: An essential tool for climate studies Dr Nigel Fox2 5 Jan 2011
        http://www.bipm.org/utils/common/pdf/RoySoc/Nigel_Fox.pdf
        (Video Seeking the TRUTHS about climate change)
        Note cloud radiative forcing (CRF) uncertainty in Nigel’s slide 14/55
        i.e. IF improve uncertainty 10x, then
        Testing 50% cloud feedback – need 20 years.
        Testing 100% cloud feedback – still need 12 years for proposed TRUTHS vs 40 years for MODIS.
        From Wielicki et al 2010.
        That indicates a very large uncertainty in clouds.

        Note Solar Influences on Climate Joanna Haigh –
        An influence of solar spectral variations on radiative forcing of climate
        Joanna D. Haigh1, Ann R. Winning1, Ralf Toumi1 & Jerald W. Harder, Nature Vol 467, 7 Oct. 2010 pp 696-699
        See especially Table 1
        Cited by Fox in Slide 17.
        That paper shows solar cooling results in earth warming!
        i.e. from 2004-2007 TSI Down UV Down BUT VIS was UP!.
        Ozone > 48 km down BUT ozone 90% confidence. Note too that the total uncertainties have not changed much over the last 40 years.

      • Girma shows the very substantial natural cycles on a long term trend as do other researchers..

        David, we would appear to have very different criteria for “researcher” and “show.”

        (i) In what sense is Girma a “researcher”? And are you judging the others as researchers by the same criteria?

        (ii) Girma is modeling temperature as a steady climb of 0.6 °C/century. How does that constitute “showing a cycle”? What is its period?

        (iii) How are you able to tell that this climb is of natural origin? You simply declare it to be, without further explanation.

        (iv) If this climb is natural, why is it appearing just now? Clearly it hasn’t been going on for the past thousand years or the temperature would have risen 6 °C over that period. Temperature reconstructions going back half a millennium such as that of Gray et al, A tree-ring based reconstruction of the Atlantic Multidecadal Oscillation since 1567 A.D. show no such steady rise, instead showing strong cyclic behavior with a period that seems to fluctuate between 60 and 80 years. If Girma were to model the data as a cycle instead of a straight line, the model would be in much better agreement with reconstructions of this kind.

        (v) Modeling climate as a linear rise fails to explain 29% of the variance in the selected temperature record, that is, r^2 = 0.71 (so Pearson’s r = sqrt(.71) = 0.84, essentially the number Girma quotes). One can account for 6% of that as short-term variance, say events of duration less than 15 years, that no one currently knows how to model accurately, but this still leaves 23% of long-term climate variance unexplained (variances between independent variables combine additively). If one is willing to settle for a model that leaves this much unexplained, one can come up with a wide range of other models that achieve just as good a fit or better.

        (vi) As an example of a model that is both better motivated and a better fit, take two cycles typical of the kind observed over the past half millennium, of respective periods 55 and 81 years and respective amplitudes 0.05 °C and 0.055 °C, and superimpose on them the expected warming from the increase in CO2 observed at the Mauna Loa observatory assuming a climate sensitivity of 3 °C/doubling, a 25-year delay between increasing CO2 and its impact on surface temperature, and a 280 ppmv preindustrial CO2 level.

        Whereas Girma’s model leaves 23% of long-term climate unexplained, this model explains all but 0.5%. It is also a better match to the past half millennium, in that it consists of cycles of a kind and period already observed instead of a straight line that appears nowhere in the last half millennium. And it is in good agreement with the well-understood physics of IR absorption by greenhouse gases, which Girma’s model ignores completely.

      • One can account for 6% of that as short-term variance, say events of duration less than 15 years, that no one currently knows how to model accurately, but this still leaves 23% of long-term climate variance unexplained (variances between independent variables combine additively).

        Correction, replace 29% = 6%+23% by 29% = 13.5%+15.5%. (I forgot to truncate the full 161 years of the HADCRUT data to the 131 years Girma was using. I’d been a bit puzzled how the short-term component could be so small, this explains it – the short-term part was 13.5%, not 6%, when the truncation is performed.)

        That is, Girma is leaving only 15.5% of long-term climate variance unexplained, not the 23% I had calculated. But that’s still nowhere near as good as leaving only 0.5% of the variance unexplained.

  46. Judith, I like your presentation.

    My favorite issue, the CO2. I think this is hot off the press:

    Productivity of land plants may be greater than previously thought
    Researchers recommend the reworking of global carbon models in Nature
    http://www.eurekalert.org/pub_releases/2011-09/haog-pol092911.php

    • This story is also being discussed on PhysOrg.com:
      http://www.physorg.com/news/2011-09-global-carbon-benchmark.html

      Big Brother is embarrassed: Climate e-mails exposed his toe!

      The owner identified himself by:
      a.) Trying to whitewash its ugly nail, and
      b.) Trying to remove stains on its Noble Prize!

      Now it is time to abandon blind, lock-step, consensus belief in:

      1. The 1967 Bilderberg dogma that Earth’s heat source is a ball of hydrogen, in equilibrium, generating constant heat by H-fusion.

      2. Auto-centric dogma that humans cause global climate change.

      These falsehoods blocked progress for four decades (1971-2011):
      http://dl.dropbox.com/u/10640850/20110722_Climategate_Roots.pdf

      With kind regards,
      Oliver K. Manuel
      http://myprofile.cos.com/manuelo09

    • Edim

      The link to the Welp et al. study on increased photosynthesis during warm El Niño years is very interesting.

      Higher productivity of land plants is being suggested, particularly during warmer El Niño years. This is postulated to be around 30-45 GtC/year higher than previously estimated. This suggested increase is more than four times as much CO2 as is emitted annually by humans!

      the oxygen atoms in carbon dioxide were converted faster than expected during the El Niño years

      I had noticed that the amount of CO2 emitted by humans bore no year-to-year correlation with the increase in atmospheric concentration (ranging from 17% to 88% on an annual basis, and averaging around 50% over the longer-term).

      However, there appears to be a correlation between the amount remaining in the atmosphere and the change in temperature from the preceding year.
      http://farm7.static.flickr.com/6088/6125488794_8ef0233067_b.jpg
      http://farm7.static.flickr.com/6080/6125478512_1eb60e073e_b.jpg

      This new study shows more CO2 conversion ”during warmer El Niño years” rather than more CO2 remaining in the atmosphere during those years, which intuitively is just the opposite of what I found, but maybe this has more to do with the one-year time lag (change from previous year) which I had built in.

      At any rate, it is interesting in that it shows that the global carbon balance estimates probably need revising. Even if it still does not answer definitively where the “missing CO2” is going, it appears that a significant portion may be going into increased land-based plant photosynthesis, rather than simply being absorbed by the oceans as has largely been assumed to date.

      Max

    • Hmmm…

      Freeman Dyson’s carbon-eating trees may be only a few gene-tweaks away.

      On a longer-term note, it might just be possible to create a virus that will GM an existing tree to make it consume and sequester large amounts of carbon. Perhaps as indigestible carbon nodules in its roots. Sounds science-fictiony today, but 20 years from now it might just be possible with the equivalent of a kid’s chemistry set.

      • Hmmm, a recipe for an anthropogenic iceball earth, if CO2 is as determinant of temperature as is thought.
        ================

      • Heh, we’ll be sacrificing virgins to get volcanos to erupt instead of vice versa.
        =============

      • I had that same thought about Dyson. But Kim, only if it gets out of control, like in a Michael Crichton novel! And we can always burn the carbon nodules to keep warm. Heh – maybe we shouldn’t shut down the coal-fired power plants yet. Keep building solar panels though; we need energy recipes for future chaos.

      • We have trouble enough controlling natural viruses, let alone artificial ones. But I’m amused at the thought of burning the nodules when it gets cold. What druid told you burning these black rocks would change the weather?
        ===========

      • Heh, we’ll be sacrificing virgins to get volcanos to erupt instead of vice versa.

        Huh? What culture sacrifices volcanoes to get virgins to erupt?

      • Bob Shaw was way ahead of you:
        http://en.wikipedia.org/wiki/Land_and_Overland
        “But the review; yes, the book deals with a strange planet, “Land”, whirling around another planet, “Overland” in such a close orbit that the two share atmospheres. The problem facing Land is that their run-away destruction of the environment (namely, the brakka trees, which they over-harvest to get at their power crystals), an act which has turned nature against them. Suddenly plagues and worse are sweeping humankind (well, Landkind) and they must escape their doomed planet. And they have nowhere to go but… up.”
        http://www.robertraymond.com/index.php/on-the-nightstand/133-the-ragged-astronauts-review

    • I think this is important. Link to abstract (article behind paywall – I thought Nature was free?): http://www.nature.com/nature/journal/v477/n7366/full/nature10421.html

      JC – perhaps a quick post?

      If land-based ecosystems do in fact cycle CO2 much more rapidly than thought before, it should provide some fodder for good debate. from an “uncertainty” standpoint – what happens to the CO2, is it immediately respired as suggested in the physorg blurb – (to quickly dampen any enthusiasm for an AGW fix or relief valve)? What are the study’s strengths and weaknesses?

  47. So, …,

    How did it go?

  48. Still hoping to be able to hear the lecture via tape!

  49. Joachim Seifert

    Dear Judith,
    page 28: Sources of Uncertainty: External forcing: “Solar and Aerosol”…..

    What if a major input parameter is missing in all models? Ever thought
    of this? A missing input parameter will necessarily lead to false 21. Cty. climate forecasts (TAR 2001 – SRES scenarios), because its effect does not
    show and then speculations (see reply of “MattStat” etc.) about
    divergences will come up…..

    Missing in external forcings are the pecularities of the Earth’s orbit,
    “orbital forcing on a less than a millenium scale”, which are erroneously
    rejected in AR4-wg1-Chapter 9, 6 and 9, declaring the Earth’s
    orbit as only a “boundary condition” and climate-“invariant”….. But,
    the Earth’s orbit is not an “aeroplane’s flight” around Sun, but contains
    “Librations”, see Wikipedia with an animated picture for the Moon – the
    Earth does an identical libration movement – missing in all models…..

    Therefore, no surprise, models MUST be wrong, only an model
    input considering the Earth’s orbital libration will produce a highly accurate forecast…… Obviously, this cannot be an AGW-forecast and can not
    be found in “peer (pal) reviewed literature”…….

    Yours JSei.

  50. Don’t know if this has been posted here. Sorry it that is so.

    The Trouble With Experts

    The new CBC documentary examines why experts are so often wrong and why we keep trusting them. Doug Dirks speaks to filmmaker Josh Freed. The CBC documentary The Trouble with Experts airs on CBC Television this Thursday, September 29th at 9 pm.

    http://www.cbc.ca/homestretch/episode/2011/09/27/the-trouble-with-experts/

    • Skepticism is seeping slowly into the MSM. Is there a plumber in the house of cards? (Sorry Kim, just trying.)

    • Raving

      There’s a paradox described somewhere of the problem with barn cats is that you can’t rely on a single one of them, and more cats are always worse than fewer, except if your barn has no cats at all. Then you get all manner of vermin.

      Oh. Experts in this example are equated with cats, not vermin, in case metaphorical reasoning is a weakness for the reader.

      And no, I’m not suggesting that those skeptical of experts are vermin. Vermin would be a metaphor for ignorance, in this case.

      Oh, and I’m not suggesting that climate, nor science, are barns or barnlike structures built of wood.

      And straw, cattle, manure, milk and roosters play no role in this allegory.

      • It’s an interesting problem. Wife’s choice of viewing pleasure was Capitalism: A Love Story. She won. I got bored.

        You forgot the poultry. Non experts also get it wrong.

      • Roosters play no role in poultry?

        Raving, has no one yet had the talk with you?

  51. Good talk. You covered a lot of material. When you related to your personal experiences were the best parts. Your answers were excellent.

    You need work on your “pointer” skills.

  52. I enjoyed the slides — this is the first chance I’ve had to go over them.

    I have a couple of suggestions. One, at some point in your exploration of uncertainty, consider the different needs of different members of the discourse. What a scientists needs may be different (I would argue is clearly different) from what the public needs.

    To a scientist seeking to understand the world in which we live, uncertainty is ultimately going to be an enemy that will have to be confronted eventually — a true “monster.” But those that apply science may find different ways of coping with uncertainty which render it moot in a particular context.

    I don’t think anything you’re saying precludes this, but I think it is worth clearly laying out what some of these strategies are. Here are a couple uncertainty-neutering strategies:

    * Seek to identify points of uncertainty that do not affect the immediate course of action. This allows us to act confidently despite uncertainty, and safely defer resolution of the uncertainty, allowing us to investigate further. One example would be the finding, after a car accident, of free fluid (presumably blood) in the belly. The source of the bleeding is very uncertain. But regardless of whether the liver is lacerated or the splenic arty injured, exploratory surgery is the correct next step.

    Or suppose you are considering constructing a building using a given material, but there is great uncertainty about the cost. You determine, however, that the material is fragile and would not result in a sturdy structure. If the material is not suitable at all, the uncertainty related to the cost can be ignored.

    *Seek to identify uncertainties with consequences that imply a natural “hedge” in terms of the outcome of interest. For example, you may be unsure as not whether a given region is going to experience x amount of warming. Your primary concern in this agricultural region is crop yields. You are uncertain what will happen with the temperature, but if you can project with confidence that warming will cause yields to fall by X amount for one crop, but rise by X amount for another, you may be able to create a crop yield projection that is insensitive to the temperature rise.

    Can anyone think of other principles by which proposed actions can be made insensitive to uncertainties?

    • Robert:
      Suppose you are considering replacing one type of energy production with another, but you are uncertain as to the cost compared to other types of energy production. You determine that wind power is unreliable, and that you would need to build a Natural Gas plant as a backup for the wind farm. The wind farm is not a suitable replacement for a reliable energy source, and uncertainty related to cost can be ignored.

      Roy Weiler

      • One challenge with wind power in colder countries is that the wind i least when it is needed the most for heating – on clear very old days.

      • David:
        No matter how you cut it, wind power is not a replacement for anything other then people running on treadmills at random times. There was a time when I saw promise to this, but reality is a good dose of cold water.

        Roy Weiler

      • Roy
        Wind has long term statistical reliability i.e. “the roaring 40s”. See
        Global Wind Power Potential
        Its important NOT to rely on it for critical issues (using heat to keep alive) when it is least available (cold clear winter days.)

        It is important to ensure costs are effective!

        See The cost of wind, the price of wind, the value of wind

        i.e. DO NOT Use wind that is 900% of conventional power because it is politically correct!
        Now if you can provide wind at 10% of conventional power – then lots of areas open up! e.g. using it to generate fuel.

      • David

        Thanks for the link. :)

        As the polar jet stream is routinely tapped with the Great Circle Route for return flights from America to, for instance, Japan, there is zero uncertainty to the question you propose.

        There is a question, however the uncertainties appear fairly low, in the business development context.

        The uncertainty is in how much of the power of the Jet Stream can be economically tapped for electric power.

        In the Pacific Northwest, the power available is most certainly in excess of current and projected needs.. is the price point below that of coal? That’s a more interesting question to me.

      • David L. Hagen

        “the wind i least when it is needed the most “

        The Polar Jetstream dominates the sky above colder countries at the 7 km+ level, providing over 90% reliability, including for clear days regardless of their age.

        The challenge you mention is merely a technical problem of failure to build 7 km tall windmills. ;)

      • Or developing 7 km high kites
        Then climate “uncertainty” – what is the probability of being able to tap the jet stream>

      • If any of that were true, then that would indeed be an example of the first case I mentioned.

        My comment is about the analysis of uncertainty, not about alternate energy sources.

      • Robert:
        There is a lot of uncertainty in these “new” energy sources!!

        Honestly, it falls within the bounds of your scenarios. Lest you be one sided.

        Solar and Wind will not be able to replace other power sources in the foreseeable future. It is simply a waste of money.

        Roy Weiler

      • There is a lot of uncertainty in these “new” energy sources!!

        For wind it is well captured by the aleatory uncertainty of maximum entropy. The movement of air has some mean kinetic energy. If you apply a maximum entropy distribution of this energy and convert it to wind speeds you end up getting the Rayleigh distribution. As scientists, whatever we can understand we can try to take advantage of. Wind is stochastically predictable in that regard. I like to use the analogy of rain — farmers have learned to manage in spite of the unpredictability of rainfall.

      • “Honestly, it falls within the bounds of your scenarios. Lest you be one sided.”

        There is nothing one-sided about an analysis of uncertainty. I deliberately selected only one (of three), very abstract, example of climate impacts, to try and avoid the inevitable digression you are pursuing. Your problem is that you cannot follow a line of reasoning until you have decided how it affirms what you already believe. You can’t participate in a neutral discussion about uncertainty without trying to start an argument about wind power. I’m not interested in having that argument right now: I’m interested in a serious discussion about the issues of uncertainty raised by Dr. Curry in her talk.

      • WHT,
        You should spend more time with farmers and less in your echo chamber.

      • WHT,
        You should spend more time with farmers and less in your echo chamber.

        I used to do vacuum chambers and have modeling of wind chambers somewhere on my professional horizon. Like farmers, who I respect, I put in my hours. Take a look at this deep analysis I did of Ontario and Germany wind energy data statistics over the course of several years.
        Ontario: :http://mobjectivist.blogspot.com/2010/05/wind-energy-dispersion-analysis.html
        Germany : http://mobjectivist.blogspot.com/2010/06/wind-variability-in-germany.html
        This was all compiled into The Oil Conundrum

        MacArthur said it like this: There is no security on this earth, there is only opportunity.

    • Robert,

      Any action taken where the result would not be ‘regrettable’ would be insensitive to uncertainties.

      Examples pertinent to AGW… improving energy efficiency of consumer products or your home, planting more trees in urban areas, utilizing ‘green’ building technologies, etc…

      For those who are truly concerned about the environment, making conscientious decisions about the products they use, i.e products or habits that are low impact on the environment, are all non regrettable actions. It’ll make you ‘feel’ better too.

      • “Any action taken where the result would not be ‘regrettable’ would be insensitive to uncertainties.”

        True, assuming minimal opportunity costs. If we can do many things at once (and we certainly can as a society) than actions that yield a positive return can neglect uncertainties that affect only the magnitude of the benefit but not the sign.

      • A lot of people are pushing “no regrets” policies as a kind of “middle way”, but they really aren’t. As worthwhile as those policies may be in themselves we shouldn’t kid ourselves that by themselves they represent a strategy to combat AGW and reduce emissions – they simply won’t make a big enough difference. Ultimately we have to make a decision whether the risks from AGW, bearing in mind the uncertainties involved, are sufficient to warrant adopting aggressive strategies to reduce emissions and whether they outweigh the costs involved in doing so. And answering “yes” to that question does mean accepting that if the uncertainties are resolved overwhelming in the direction of less harm from AGW there may be “regrets”.

        I have no intention of arguing here about what is the correct course of action (although my sympathies will be pretty clear to regular readers) but we should at least be clear and honest about the choices we face. So by all means let’s pursue these “no regrets” policies, but at least admit that to argue for only these policies is to argue that we should not have a serious strategy to reduce emissions and combat AGW, it is not a compromise or “middle way”.

      • aa,
        Not one of the policies pushed by the AGW community has or will make any difference in controlling CO2 or impacting cliamte by way of controlling CO2.

    • I’m not sure your principles even make sense:

      “Or suppose you are considering constructing a building using a given material, but there is great uncertainty about the cost. You determine, however, that the material is fragile and would not result in a sturdy structure. If the material is not suitable at all, the uncertainty related to the cost can be ignored.”

      Unless you need the structure immediately in which case the uncertainty in cost and assurance that the building will not be sturdy are both moot.

      The problem with your principles Robert is that they either apply to no situation or when you apply them to situations it is clear the principle is faulty or fails to account for something.

      • “Unless you need the structure immediately in which case the uncertainty in cost and assurance that the building will not be sturdy are both moot.”

        You are assuming no other material is available, and the need is absolute. Neither of these conditions are specified or implied.

        “The problem with your principles Robert is that they either apply to no situation or when you apply them to situations it is clear the principle is faulty or fails to account for something.”

        Evidence for that? Please describe every possible application of these principles and prove that they are all faulty.

        Maybe you haven’t been exposed to thought experiments before. You seem a little unclear on the concept.

    • Can anyone think of other principles by which proposed actions can be made insensitive to uncertainties?

      Category:

      *Seek to identify uncertainties with consequences that imply a natural “hedge” in terms of the outcome of interest.”

      We are uncertain of the best long-term replacement for dwindling fossil fuel resources as an energy source: we know the natural (and insurmountable) limitations of wind and solar reliability and the (post-Fukushima) political fears regarding the safety of conventional nuclear fission, also with regard to the spent fuel problem.

      We can “hedge our bets” a) by trying to develop technologies for storing electrical energy from unreliable sources inexpensively and b) by working on the development of fast breeder fission reactors generating far less spent fuel plus nuclear fusion technology.

      Max

      • “Category”

        My question was about other principles, not applications of the principles I outlined. But thanks for your reply, although I disagree with many of the assertions you assume as true (dwindling? insurmountable?)

      • “dwindling” (as applied to global fossil fuel resources): these are limited (by definition). The World Energy Council has recently published a study summarizing both the “proven reserves” as well as the “inferred possible total resources in place”. The latter should last us at least 200 years, and would theoretically add around 670 ppmv CO2 to the atmosphere, bringing us to an absolute maximum of 1060 ppmv when they are all gone.

        “insurmountable” (as applied to the unreliable nature of wind and the fact that solar cells only produce power when the sun is shining): there is not much we can do about this problem, ergo it is “insurmountable”. As indicated we can resort to a substitute process of developing inexpensive methods of storing electrical power from the time nature decodes to provide it to the time that humans require it in order to get around this “insurmountable” problem.

        Hope this clears up the use of these two words for you.

        Max

    • “But regardless of whether the liver is lacerated or the splenic arty injured, exploratory surgery is the correct next step.” When I had multiple internal haemorrhages after being run down by a car while on a motorcycle, no exploratory surgery was undertaken. Perhaps because I wasn’t expected to live (except by myself), the doctors wouldn’t touch my shattered leg because they thought that to do so would be fatal; maybe also with exploratory surgery. So the “correct next step” is dependant on specific circumstances.

  53. Dear Judy,

    Thank you for a great talk, and an interesting introduction into the literature of uncertainty. I look forward to reading your paper as well! I did not review your presentation prior to attending, but I wonder if you might consider adding another hypothesis to the list on slide 43, “Why is there such strong belief among scientists in the IPCC attribution statement?” I am sure someone else has hypothesized this, but I wonder if belief in the statement affords the believer a sense of empowerment to make effective change. If one believes that anthropogenic greenhouse gases are responsible for the increase in the observed surface air temperatures, and those are in turn (allegedly) responsible for extreme weather events, then extreme weather events can be lessened by reducing the greenhouse gases – voila! – problem fixed. I think that the example of scientist exploring geo-engineering solutions as an alternate means to “control” the weather/climate system is indicative of some scientists needing to believe they have some control in what they perceive as a chaotic and complex system. This gives them comfort. This seems somewhat related to the “magical solutions” that Roger Pielke Jr. talks about.

    My own field – fine art – generally welcomes uncertainty and ambiguity. I have a couple other thoughts about your presentation if you’d like to hear them, but overall, a great presentation, and I am glad I schlepped across town in the driving rain to see you speak.

    All the best!
    matthew

    • matthew hincman

      You have presented an interesting hypothesis to explain confirmation bias.

      Which skips the step of proving that the result is biased.

      It may simply be that the scientists answering are giving an answer that is exactly what it appears to be on its face, the answer they conclude is correct by scientific reasoning.

      (Which is a terrible story, having no narrative value, so one understands why, with its lack of nuance and ambiguity, it would be of little value to fine art. Please enjoy the paradoxic irony that by applying your technique of interpretation to your technique of interpretation, I have become you.) ;)

      In the dénouement to my anticlimactic, indeed anti-literary, thesis, I suggest it more likely there were a mix of reasons, but the main one was scientists tend to value information, mathematical rigor and precise logic.

      • Bart, my recent post on the previous thread is pertinent here:

        The Economist had an interesting and highly pertinent piece recently on “When elites get it wrong.” An extract:

        Why do elites (people who almost by definition are well-informed and practised in important decision-making) get it wrong? A shallow, though correct and often neglected, answer is that judgement is a completely different mental faculty to intelligence or experience. Clever people can analyse an issue forensically but draw the wrong conclusion. Stupid people can do no analysis at all but still arrive at a sound judgement through sheer instinct.

        But we need a fuller answer than that, and a persuasive one is proffered by Stephan Shakespeare, the head of YouGov, a polling firm. As well as measuring opinion for a living, Mr Shakespeare is interested in the underlying science of opinion: how humans come to think what they think. Informed by scientific source material, and his own experiences as a pollster, he has begun to espouse what I will call (in anticipation that it gets turned into a Zeitgeist-y book before long) Shakespeare’s Law. This is the theory that humans basically don’t care about being right. We are hard-wired to hold opinions that align ourselves with a crowd (not always the majority crowd, though that is the strongest impulse). We are not hard-wired to form opinions through coldly objective and impersonal analysis. We do not feel much better for having been proven right about something. On the other hand, we receive a dopamine boost when we shift our opinion from a minority view to a majority view.

        If you accept Shakespeare’s Law, the flaws in elite thinking are easier to account for. The “crowd” that Mr Shakespeare speaks of does not necessarily denote the public as a whole, but the social network of a given person. The social network of a member of the elite consists of other members of the elite. Journalists, politicians, mandarins and businessmen tend to mix among themselves, not with Everyman. The social (or, more accurately, neurological and psychological) pressure to agree with one’s peers applies even to this tribe of hyper-educated people. They adopt opinions that align themselves with their peers, which in 1981 meant disdain for Mrs Thatcher and in 2001 support for the euro. Opinions that literally make them feel good. Rigorous analysis has little to do with it, even if they sincerely believe otherwise. This lack of rigour means that the opinions carry a strong risk of being wrong. Basic flaws and inconsistencies in their opinion go unexamined because, after all, being right is, whether they realise it or not, not their priority.

        Of course Shakespeare’s Law also applies to hoi polloi. Their views are just as moulded by an impulse to belong. But they don’t purport to be all-seeing elders, and they don’t have the levers of power at their finger tips.

        http://www.economist.com/blogs/blighty

      • Pretty self-evident, Faustino dear

        Seen most strongly in bureaucrats and politicians, where *winning* gains the most in-group plaudits, so they don’t much mind being wrong or looking stupid, but they HATE losing

      • Mmm, can’t recall when I was last called “dear.” But I agree that with bureaucrats winning the argument is very often more important than (a) being right or (b) serving the public interest.

      • On the topic of “getting it wrong” it is difficult to imagine a more elite authority to appeal to than an Economist op-ed piece.

        Where no prediction is possible due the nature of the system, many times experts, elites, professionals, ad so forth are persuaded to make predictions.

        The more experienced the elite, the more clearly they preface and footnote their ‘predictions’ with the very clear and specific limits on prediction. Meteorologists, for example, will state, “This five day forecast has no better likelihood than random chance of being accurate,” where applicable.

        And yet, educated, literate critics will read the prediction, ignore the parameters, and take this cherry-picked portion of the evidence and compare it to the outcome and announce the elites wrongness.

        Which proves some critics incapable of being trusted to handle evidence.

        The evidence suggests humans care a great deal about being right, simply based on the price humans pay in that endeavor.

        The evidence also suggests that at least some critics are willing to duplicitously manipulate reasoning for ulterior motives or due incompetence.

        One suggests incompetence the greater part of the problem.

        Some outcomes can’t be meaningfully forecast.

        Get over it.

      • Bart R,
        “Get over it”?
        You brush off the demonstrated problems with the AGW promoters and you blame the critics and actually think it is credible to tell even someone asking mild questions to “get over it”?
        No wonder you guys are losing.
        You don’t even get it.

      • Which skips the step of proving that the result is biased.

        Excellent point. Clearly at least one side of the climate debate is biased — each side is certain the other side is wrong, and therefore presumably biased. The question is, which side?

        As long as neither side can give better than handwaving arguments that “most” global warming since 1970 has been of human vs natural origin, we’ll only have the gut feelings of the two sides.

        I’d love to see a rigorous argument for a more precise estimate than one based on either “we haven’t seen much natural variation in the past four decades” or “we haven’t seen much variation attributable to humans in the past four decades.” That’s basically what both sides are claiming.

        If it turns out that 50% is human and 50% natural, then I’d say both sides were biased. As things stand both sides seem firmly convinced that the result must be at least an 80/20 split one way or the other and nowhere near 50/50. But mere conviction leads to confirmation bias, and is a far cry from a rigorous analysis showing that the 20% side cannot be any greater than that.

        If someone has better than a handwaving argument for such an upper bound on the 20% side of whatever they consider the split to be, a lot of people would be eager to see it. Or at least should be, otherwise the whole debate becomes indistinguishable from a religious disagreement.

      • Show me the CO2 effect.
        ========

      • Heh, Joshua, I love the little ironies you spout so innocently.

        Which of my many innocent ironies are you speaking to, kim?

        I know that it’s hard to select just one from among so many – but it appeared that you had a particular one in mind. Which one would that be?

      • Vaughan

        I suggest that if “sides” are required to be defined that the following is a fair summary:

        One “side” would be those that believe steps need to be taken to eliminate human caused CO2 emissions as quickly as possible in order to avoid a disastrous future.

        The other “side” is made up of those who are doubtful of their conclusion for a variety of reasons.

        Isn’t that as fair summary of the “sides” as any?

      • Rob –

        I think that is a fair summary of the positions of those on the extreme ends of the debate.

        There is an unquantified middle, however:

        Those who think that CO2 emissions are likely to contribute to natural variations that may take place, and that in light of that likelihood, or even in light of a lesser probability, it makes sense to fully investigate the costs and benefits of different types of mitigation.

        Those who think that CO2 emissions are not likely to contribute to natural variations that might take place, but in light of the possibility, and the potential impact of that possibility, it makes sense to fully investigate the costs and benefits of different types of mitigation.

        Those who are not convinced either way about the likelihood that CO2 emissions will contribute to natural variations that might take place, but in light of ancillary benefits that might result from CO2 emissions mitigation, it makes sense to fully investigate the costs and benefits of different types of mitigation.

        Perhaps there are other sides?

      • randomengineer

        Joshua

        There is an unquantified middle, however:

        Nice point, and interesting.

        I reckon most folks would be tickled to investigate strategies/costs/etc if only in the same thinking as chance favouring the prepared mind. If man is ruining the planet, it would be helpful to know how and what might be done. If man is not, then the money spent still advances understanding in many areas and is worth it overall.

        The disconnect comes only when a) we are told that it is certain that this is the case and act/pay now or else, or b) invocation of the worst possible ‘fraidy-cat variant of the precationay principle is used as the club to force us to act/pay now or else.

      • RE –

        No disagreement with you last post in the abstract (in other words, applying the principle to both sides of the debate). I would argue, however, that your observation necessarily applies to both sides of the debate, in contrast to your previous post that the hand-waiving (i.e., “alarmism”) exists solely on one side. Some participants, and not all, on both sides are claiming certainty, and some participants, although not all, on both sides are invoking worst-case scenario “fraidy-cat” variants as they fit with their political agendas.

      • Oh, blah, Joshua; it’s settled versus unsettled. The certainty is monstrously assymetric.
        ==========

      • The certainty is monstrously assymetric.

        Really? So, I should just dismiss all the post I read claiming that anthropogenic CO2 can’t change the climate?

        Ok.

        And I should just dismiss all the posts stating that the “globe is cooling,” that “warming has stopped,” etc.?

        Ok.

        And I should dismiss all the posts stating that ocean acidification isn’t happening?

        Ok.

        And I should dismiss all the posts stating that even if ocean acidfiication were happening, it wouldn’t be a problem?

        Ok.

        And I should just dismiss all the posts stating that increased CO2 emissions would be beneficial?

        Ok,

        And I should dismiss all the posts stating that climate scientists are “frauds” that have invented the theory of AGW so they can maintaing their funding?

        Ok.

        And I should just dismiss all the posts stating that climate scientists are only advocating for policies because they’re statists trying to destroy capitalism to advance their socialistic agendas?

        Ok.

        And I should just dismiss all the posts stating with certainty that climate “skepticism” is on the rise, and all the certainty of attributing that rise to “climategate.”

        Ok.

        The certainty that GCMs are unable to provide result useful for estimating future influences of anthropogenic CO2 emissions?

        The certainty that increased environmental CO2 isn’t attributable to anthropogenic emissions?

        The certainty that cosmic radiation has caused recent changes in climate?

        The certainty that feedback from clouds is negative?

        The certainty renewable energy is a dead end?

        The certainty that taxes on carbon will cause mass starvation?

        I could go on, but I should just dismiss all of that, and any other certainty I see among “skeptics,” and accept that the certainty is asymmetric – even though the IPCC has qualified AGW as 90% likely to explain more than 50% of recent warming.,

        Gotcha.

      • Your bias has blinded you. Hardly anyone is certain of any of that. Sure, there’s lots of opinion out there, and CAGW is one of them.
        =================

      • Hardly anyone is certain of any of that.

        Oh. Ok.

        So I should ignore what people actually say, and instead I should rely in your interpretation that what they actually believe is in contradiction to what they say?

        Because you’re certain about your interpretation, right?

        Take a wander around a coupla threads at Clmate Etc., or WUWT . Read again what people write and get back to me. We’ll talk.

      • randomengineer

        JOSHUA — I would argue, however, that your observation necessarily applies to both sides of the debate, in contrast to your previous post that the hand-waiving (i.e., “alarmism”) exists solely on one side.

        The handwaving of the “oh no it ain’t” side is immaterial in that the “I’m claiming it’s warming” side hasn’t proven its case. If the “pro” side proves the case the “anti” side doesn’t exist.

        e.g. I’m not going to tell you your cat really isn’t taking orders from aliens from uranus unless you claim that your cat is taking such orders. It wouldn’t occur naturally to anyone that it’s even possible your cat could do this. No claim? No anti-claim side.

        In my mind the “anti” side disappears in a puff of smoke when the “pro” claim is substantiated with a clear and unambiguous demonstration that paleoclimate is understood and can be modeled accurately. If you can take an arbitary set date from the past and show what happened this says that the probability of predicting the future with skill is high.

        Your post though speaks to the handwaving. A claim is a claim is a claim is handwaving until the claim can be proven beyond any notion of doubt, and the onus is on the claimant. In your mental model you’re looking at the notion that you reckon we have some understanding therefore the onus is on the “anti” side to prove otherwise. When someone profers doubt of the claim, the “pro” side zealots of course sieze the opportunity to cast doubt on the doubter (evil uneducated bible thumping republican screeds) and then make the additional claim that the doubter is anti-science.

        The zealotry is where the wheels come off. Many doubters are saying “wow, it’s really impressive, but it’s not quite proven.” It’s not handwaving to conclude that the case isn’t proven any more than it’s handwaving for someone to say why they think this. You’re imputing a form of symmetry that simply doesn’t exist.

        Summary — Claimant must prove the case, no different than how all of the western tradition of law works.

      • Sorry Kim but Joshua has you on that one.

        Over the course of the last 4 years I have noted a distinctive turn in skepticism. Skepticism used to be expressed in the form “it hasnt been proved” At its best, in McIntyre, it merely made the observation that the claims of the science were over stating the case of certainty. Early on Anthony also adopted this approach. The data havent been properly handled.

        But lately, I cannot put a date on it, you see more and more claims of positive knowledge from the skeptical side: scaffetta: cycles exist. Willis: the climate has a thermostat. and a whole raft similar claims, see Joshua’s list. On the whole the “science” produced by the skeptic side is pretty thin. I’ve asked many of the posters at WUWT for data and code. Note, I dont demand that they publish in peer review, just that they properly document what they do.. what has been the response to these requests
        Zip.. zero.. nada ( except Willis of course who shares my values in that regard) There is an asymetery of outrage at the lack of transparency.
        Skeptics were glad to join me when I asked AGW folks for code and data, but put the other foot on the their neck and .. crickets. The skeptics were fast to doubt every sentence and fact in a Mann paper. Rightly so. science advances through adversity. But none of them takes the same rigorous approach ( save McIntyre ) to a paper by spenser or lindzen. Those are accepted without question. The are not skeptical of their own. One minute they will slam the global temperature record as a pile of crap, and the next minute they will accept it if it promotes their favorite theory of the day.

      • What a waste. You willfully won’t see the point. Settled vs Unsettled. Settle down and think about it for a minute.
        =========

      • RE –

        It appears I didn’t make my point sufficiently clear.

        IMO, the “hand-waiving” on the “skeptical” side are not in the form of statements that question the certainty of AGW theory – any more than it comes in the form of the IPCC statement that AGW is 90% likely to explain more than 50% of recent warming.

        The “hand-waiving” from the “skeptical” sides comes in the form of post after post after post at “skeptical” websites attributing the theory of AGW to a socialist cabal that is milking a rigged funding scheme so as to promote their agenda to destroy capitalism without paying heed to the hundreds of millions that will starve as a result. Or the post after post after post that the final nail has been driven into the AGW coffin. Or the post after post after post saying that the globe has cooled, or that it’s obvious that the sun explains recent warming, or that increased CO2 is beneficial, etc., etc., etc.

        And of course, the “hand-waiving” that the “hand-waiving” is solely on one side or the other.

      • Right, moshe, let’s not have this outbreak of imagination.
        =================

      • Sorry Kim but Joshua has you on that one.

        lol! What else is new?

        How humiliating to be “had” by an IDJT?

      • How do you propose, moshe, that the certain conviction of certain innovators will become settled science without the cut and thrust of events? You should pursue the will-o-the-wisp to grasp what is there, but don’t forget the zombie stumbling at your heels, though, for it is certainly there.
        =========

      • Heh, Joshua, I love the little ironies you spout so innocently.
        ============

      • Once you grasp the real Will, you can slay the zombie. Keep searching, moshe.
        ===============

      • And there I was certain that I laid this into the proper nest.

        http://judithcurry.com/2011/09/28/uncertainty-monster-visits-mit/#comment-117156

      • Skeptics were glad to join me when I asked AGW folks for code and data, but put the other foot on the their neck and .. crickets.

        That is a prescient observation. I spent several years analyzing oil depletion and now about a year doing my variation of climate science. I wrote the common theme down in my book “The Oil Conundrum”. Read to the end of this excerpt:

        Moreover, generating a good quantitative approach provides needed ammunition to defend against cornucopian arguments. Optimists such as Michael Lynch and Peter Huber, who try to refute possibilities of energy shortages, regularly dispute the claims of oil analyst pessimists. Several of Lynch’s papers try to debunk pessimistic scenarios and in pure rhetoric he nearly succeeds. By one measure, he makes a good case by poking holes in the incomplete nature of the heuristic theories of analysts such as Laherrere and Campbell. But Lynch’s ideas have no better than a heuristic nature themselves. So it becomes a battle of heurism versus heurism or empirical data versus other empirical data. With a good formal counter-argument in
        place, Lynch and Huber would have to contend with justifying formal arguments of their own, and from what we know in regards to global warming arguments the critics have few theories of their own.

        So when I suggest that someone like McIntyre branch out in and organize some physics discussions, his acolytes come running to his defense: “he is retired, so can do what he wants”, “”it’s not your blog”, “you just want to silence his voice”, etc.
        Not exactly, I just want some of the skeptics to step up to the plate, and lift the the proverbial finger. As Mosher said, ..crickets.. AFAICT, Mosher can talk the talk, because he walks the walk.

      • randomengineer

        If someone has better than a handwaving argument for such an upper bound on the 20% side of whatever they consider the split to be, a lot of people would be eager to see it.

        It all depends on what you consider handwaving. To me the existence of the various holocene warm periods (e.g. roman optimum, MWP, etc.) are clear and unambiguous evidence of natural variation. This isn’t handwaving; it’s data.

        Handwaving instead is here: it’s the lack of being able to explain these periods in a convincing manner (i.e. set a model to conditions of 850 CE, let it cycle for 800 years, and it should show the MWP and the LIA happening) and paleoclimate arguments are believable.

        In other words, the handwaving is solely on the “alarm” side until such time as that side can prove that it can handle paleoclimate accurately. What exacerbates the feeling of excessive, over the top handwaving is the existence of hockey sticks that require the MWP to not exist.

        It’s all about paleoclimate. Prove that this is understood, and the arguments cease.

      • In other words, the handwaving is solely on the “alarm” side…

        lol!

      • Joshua,
        Thanks

      • ‘It all depends on what you consider handwaving. To me the existence of the various holocene warm periods (e.g. roman optimum, MWP, etc.) are clear and unambiguous evidence of natural variation. This isn’t handwaving; it’s data”

        seriously. I find none of the reconstructions particularly robust or relevant to the real question. Its amazing how people look at one set of data ; the temperature record and are very demanding about the documentation and proof, but when it comes to their pet theory.. ( the MWP is a theory ) they are very lax.

        Also when it comes to their explanations they are very undemanding. “natural variation” explains nothing. It is a label for data that wiggles.
        So yes the data has wiggles. When we see a volcano and the data wiggles down, we do not say “natural variation” we explain one in terms of the other. When we see temperatures going up claiming that “natural variation is the “cause”, explains nothing. It merely recapitulates the observation in other terms. natural variation explains nothing predicts nothing. Its is synonymous to saying ” we dont know”

      • I don’t think there is a valid argument for man-made impacts being more or less than 50/50. There is a fair argument that man-made CO2 is responsible for less than 50 percent.

      • @Dallas I don’t think there is a valid argument for man-made impacts being more or less than 50/50. There is a fair argument that man-made CO2 is responsible for less than 50 percent.

        Even though my position is based on a fair amount of data and analysis it ends up not being hugely different from yours. Assuming we’re talking about the temperature rise during the period since 1970, I would say based solely on the HITRAN tables and the CO2, temperature, and fuel records, and ignoring general circulation models (sorry, guys), that CO2’s contribution is in the 40-70% range.

        On the same basis I estimate the overall anthropogenic contribution at 80%, but with considerable uncertainty due to our continuing lack of understanding of how quickly surface temperature responds to the combination of radiative and aerosol forcing, and to the difficulty of estimating mid-19th-century CO2 – simply varying the estimate of that quantity between 275 and 285 ppmv can make a big difference to estimating the overall anthropogenic impact today.

        @randomengineer It’s all about paleoclimate. Prove that this is understood, and the arguments cease.

        Appeals to paleoclimate, which both sides of the debate like to make, don’t carry much weight because paleoclimate has no relevance to modern global warming. The modern rate of increase of CO2, which only half a century ago was quarter of a percent per year, has since jumped to half a percent with no sign of easing up. Had CO2 sustained that rate say 12,000 or 24,000 years ago even for just three centuries, starting from 300 ppmv, it would have shot up to over 1300 ppmv. There is no sign in the recent geological record of CO2 having climbed anywhere near that high, even over a thousand years let alone 300.

        The current rate of climb of CO2 is something this planet is very unlikely to have ever experienced before over any sustained period. Maybe over a decade, for example if some megavolcano had released an enormous quantity of CO2, but not over much longer periods than that.

        Conceivably a comet could have delivered a load of CO2 all at once. Ootsubo et al report seeing mixing ratios of close to 30% in some comets observed from space (terrestrial observation of cometary CO2 is beyond the current state of the art due to jamming of that signal by the CO2 in our own atmosphere). Such a comet having the same mass as Halley’s comet, around 200 gigatonnes, could deliver say 50 gigatonnes of CO2 or 14 GtC (gigatonnes of carbon). The atmosphere currently contains 3000 gigatonnes of CO2 or 830 GtC, so such a comet would add about 1.7% to atmospheric CO2, the amount humans are currently adding in three years. Hence it is very unlikely that Earth ever experienced a sudden big jump in CO2 due to a comet striking it. Over billions of years cometary CO2 could accumulate, but not at anywhere near the modern rate of 0.5% per year.

      • The current rate of climb of CO2 is something this planet is very unlikely to have ever experienced before over any sustained period.

        This is the part that should make the intellectually curious scratch their heads. The concept of time has a huge dynamic range, and the fact that humans can compress this so easily is spooky IMO. We have crude oil reserves that built up over millions of years and we can deplete these by half in 150 years. We have records of temperature change that span geologic time and now things are changing over dozens of years. The list of these fast man-made changes is endless.

      • We have crude oil reserves that built up over millions of years and we can deplete these by half in 150 years.

        Good point. One argument I haven’t seen skeptics make for why CO2 won’t go much higher is that if the first half only added 110 ppmv to the preindustrial 280 ppmv level, why should we expect the second half to add any more than another 110 ppmv? This would bring CO2 up to a tidy 500 ppmv.

        Currently CO2 is accumulating at 2.4 ppmv/year, which is 2.2% of the 110. If that 2.2% CAGR keeps up, the other half will be gone by my 99th birthday in 2043: 110\times 1.022^{32}=220.

      • why should we expect the second half to add any more than another 110 ppmv?

        Coal and all the lower grades of oil are the wild card in all of this. The processing energy required to process tar sands, for example, is pretty significant. Since natural gas is used to separate the oil from the sand, these lower grades act like carbon multipliers. It’s not only the final emissions that are important, but all the precursor processing that adds up.

        If we consider all the grades of coal from anthracite, to bituminous, to lowly lignite, with each lower grade more available, then we can start seeing more emissions than what we originally anticipated. I think this consideration is what drives the reduced emission policy more than anything else. Crude oil production will slow down, but all the other low-grade multipliers will take its place.

        A secondary consideration is that the classical oil production curve is symmetric, looking like a bell curve. This means at the peak, we have used up half the production. We are at a peak plateau now and so the halfway point is a convenient shorthand. However, the reality is that the production profile is actually asymmetric, with a heavy tail of production yet to come. It’s a quirk of the original heuristic modeling that Hubbert chose a symmetric logistic curve to describe the production profile, but the laws of diminishing returns only work that way under specific conditions. So we will likely have more than half left to go for oil, but spread over a longer time.

      • Vaughan, That sounds about right. I am thinking anthropogenic other than CO2 is about 30% to 50% of Anthro impact and Natural increase from the little ice age is 15 to 30%, since the Northern hemisphere is showing the most impact. So just let AGU guys know that a fisherman with too much time on his hands agrees with you :)

      • Bart,

        I introduced this particular hypotheses in relation to the eight others Judy posted in her presentation (slide 43). The question these hypotheses attempt to answer is: “Why do scientists believe in the IPCC attribution statement.” Regardless if the attribution statement is true or false (Most of the late 20th C. warming is very likely attributable to human influences – I am paraphrasing), it is Judy’s opinion that there is such a high degree of uncertainty in this statement – and the IPCC’s report- that one cannot attribute belief to the science itself, but rather to other factors. Her presentation is meant to challenge the assumption that “the answer they conclude is correct by scientific reasoning,” as the reasoning in the IPCC report doesn’t account for uncertainty. Thus the reason for her presentation, the eight hypotheses that she introduced, and the one I thought might also be plausible.

        Cheers,

        matthew

      • matthew

        Why do scientists believe?

        That’s a kinda loaded phrase, to many scientists. I’m puzzled by Dr. Curry’s preference for the word ‘belief’ over ‘agreement’.

        Try it as “Why do scientists agree?”

        See, right away less religious overtones, and disposes of a needless assumption that some belief in any way affects the agreement observed.

        And while Dr. Curry’s view of uncertainty might be considered, it appears you may have convolved it in forming your hypothetical due ambiguities.

        The 97% agreement with “Most of the observed increase in global average temperatures since the mid-20th century is very likely [>90%] due to the observed increase in anthropogenic greenhouse gas concentrations,” might not indicate strength of belief, but rather habit of expression.

        Specifically, do you see the word “believe” anywhere in the statement, or in the question about it? No. The statement says “observed” and the question says “agree”.

        That is, it is entirely habitual to discard expression of uncertainty, and it is not always entirely incorrect, when answering certain types of questions.

        As a simple technical question, with the graphs, data and reasoning widely available, the technically correct statement is that the observed increase in temperatures is due the observed increase in concentration, all other things held to be equal, discounting unknowns and needless assumptions. These last two conditions are generally accepted conventions, one is called “ceteris paribus” and the other, “Occam’s razor”.

        The answer says very little of belief or opinion, if what the question is testing is mere technical competency and unspoken conventions.

        One therefore can attribute nothing about belief based on the above test, except the belief in Dr. Curry’s good intentions.

        Dr. Curry’s intentions do not meet the standard of proof.

        So the task remains to you to demonstrate confirmation bias, which has a much steeper test than mere assertion, however many slides are used.

      • Der Bart,

        Good point about the use of “agree” vs. “belief”. We should be asking Dr. Curry about why she chose “belief” over “agree”, but I am not sure it would change Dr. Curry’s presentation much. I agree with your observation that much of the current climate debates are framed with religious overtones – from the use of the words “heretic”, to the more elaborate classifications such as:

        http://thethinkerblog.com/?p=2670

        etc., etc.

        In her talk, Judy confessed her own confirmation bias in regards to the attribution statement. This was her proof of at least one climate scientist who “believed” the attribution statement. In her slide 43, she indicates the reasons for her confirmation bias in red, even thought at the time (2006-2008) she had reservations about the lack of transparency about uncertainties in the findings.

        Judy’s talk included hypotheses about why scientists might believe in the statement, including why she believed and supported the statement. Her own reasons for agreeing with the statement had little to do with the science, but rather a host of other reasons. She hypothesizes that other scientists may also agree with the statement for reasons other than the science (she may be wrong). I am happy to put forth a hypotheses that could turn out wrong, and feel no compulsion to create certainty in this by demonstrating confirmation bias. Rather, if confirmation bias does (did, could possibly) exist in relation to agreement with the IPCC attribution statement, why might it be there. I don’t need to prove it to think about it, or think it is an interesting issue.

      • matthew

        “Der” Bart? While flattered, must admit confusion. There are so many Barts better suited to the title.

        Reasoning from the particular to the general always makes me uncomfortable.

        Implicit in the “Judy Confessional” logic is that Dr. Curry is typical of all scientists in all ways important to the question under consideration — a bold and unnecessary assumption.

        Examining one’s own bias is a good thing to do, of course.

        And of course, any one person may come to different conclusions about herself than others may.

        Such examination is informative and exemplary, but hardly evidentiary.

        MIT has changed much, I think, since.. the deep past. It expresses more courtesy these days, is nicer overall. I think it great that MIT has put so many of its courses online and made them freely available. That reflects a longstanding core value of the institution, one that increases MIT’s value.

        I think it great that MIT invites Dr. Curry, who has much of real value to say and can inspire a great deal of interesting and productive debate — far more and better than most who host climate blogs — not despite, but because of Dr. Curry’s differences from the consensus.

        It sounds, however, that MIT in growing more polite has become less interesting; it’s greater diffidence sounds like lesser willingness to challenge and investigate. This is unlike the MIT I expect, and not an improvement.

        I don’t need proof to think about interesting questions, but I do need a reason to think them interesting.

        Otherwise I would speculate about bias that isn’t there, wasting precious time, reaching meaningless conclusions due a priori logic.

      • Thank you Bart for such a thoughtful reply.

        You are welcome to your assumptions about MIT today, although, as you say, it may be a “bold and unnecessary assumption”.

        Speculation is by its very nature filled with uncertainty, and unless clairvoyant, one is bound to speculate incorrectly at one point or another. Science, culture, and the whole of human endeavor are bound up tightly with speculation in the face of a priori logic – some of which concludes with meaningless conclusions; some brings us extraordinary insight; and the bulk of which is probably insignificant either way – but which marks us as thinking, living beings.

        If you have ever been wrong, then in your own mind, you must certainly have been “wasting precious time”. But I would counter your time was well spent, and led you to other discoveries and new ways of seeing and thinking.

        cheers, matthew

    • You make an excellent question.
      When you see the pattern of IPCC claims being withdrawn, a tightly controlled small group in charge of the message, the reaction of that small group when faced with counter-claims, your point about empowerment makes a great deal of sense.

  54. Replying to WHT’s comment earlier in the thread where he writes: Wind is stochastically predictable in that regard. I like to use the analogy of rain — farmers have learned to manage in spite of the unpredictability of rainfall.

    This point and can be summed up in the value of wind powered water pumps versus wind generators of electrical power. It’s all a matter of storage.

  55. JC:

    “There is no question that the climate is warming; the issue is what is causing the warming.”

    “It is very difficult to separate natural variability from that caused by humans.”

    Thanks JC for that.

    However, the climate is warming only at a rate of 0.06 deg C per decade, not IPCC’s about 0.2 deg C per decade.

    Also a warming like the recent warming of about 0.16 deg C per decade for about 30-years did occur at the beginning of the last century. As a result, the recent warming is not unprecedented.

  56. Thought you might find this post interesting Dr. Curry.

    Ocean Acidification — a little bit less alkalinity could be a good thing
    excerpts:
    Yes, we should watch and monitor the oceans careful. No, there is no chance the Great Barrier Reef will be gone in the next 100 years: 1103 studies show that if the worlds oceans were slightly less basic then marine life as a whole will be slightly more likely to grow, survive, and be fertile.

    That doesn’t mean we should torch coal seams for the fun of it, but it does mean we can afford to hold off on the oceanic panic for a century or so while we figure out how to make solar and wind power work ( in the event that we might need them, and in the event that they might “work”).

    source: http://joannenova.com.au/2011/09/ocean-acidification-a-little-bit-less-alkalinity-could-be-a-good-thing/

    • John – Ocean acidification is somewhat off-topic for this thread, but probably deserves a thread of its own, and I’m hoping Dr. Curry will eventually be able to cajole an expert on this topic to do a guest post- perhaps Ken Caldeira. It’s been called “the other CO2 problem”, and while I agree with you that its threat to marine life is not severe at current ocean pH, the possibility of a doubling or near doubling of hydrogen ion concentration over the next century is a cause for some concern. The Great Barrier Reef will probably not disappear, but its calcification rate is already declining, and eventually that will become manifest in a loss of reef mass.

      There is considerable literature on this that deserves to be explored, but I can’t say the same for the claims made for “1103 studies” showing a benefit. I visited that list of studies a few months ago, and found the claim to be spurious. Some of the studies were very unconvincing, but more often, the studies themselves were reasonably credible, but their results were misrepresented by the site to reach conclusions unwarranted from the studies themselves. In any case, a few comments in this thread can’t do justice to the topic, and would be an invitation to cherry picking, and so I’ll hope the opportunity arises for a thorough discussion later.

      • Thanks,
        Great reply Fred! If there is a credible threat, it deserves to be fielded before Big Al convinces everyone its a fraud.

        Sorry for the off topic post.

      • Fred,
        You lost on OA from the start.
        You have never- never ever- bothered to respond to the studies showing it is not a problem except to relentlessly repeat your talking points.
        Your inability to engage on the topic beyond repeating the few talking points on OA really takes away from your other areas of more reasonable discussion. But hope blooms eternal, since you are evolving away from the alarmist stuff on CO2 in the atmosphere.
        So good luck. Take that first step.

      • A little OT but not too far. A healthy reef is pretty important in my current line of work. One of the larger causes of damage to it is sand, from some other location, here in the Keys. Saharan dust about ten years ago did a good bit of damage and Hurricane Wilma churned up a lot of Bay Side sediment along with the currents coming from an odd angle. No sign of CO2 bleaching yet. Interestingly, transplanted corals seem to do quite well.

  57. However, the climate is warming only at a rate of 0.06 deg C per decade, not IPCC’s about 0.2 deg C per decade.

    If you are willing to settle for a model of climate with an r^2 of 0.6 then you can find a wide range of such models that will prove anything you want. Girma and Arfur Bryant offer as their model of climate a straight line fit to the last 160 years of temperature. This gives an r^2 of 0.63 when short term events are included and 0.77 when everything shorter than 15 years is excluded.

    A literal hockey stick model defined as a trendline with a sharp bend at one point can do better. How to choose between the two? If you have a physical model of what’s causing the rise that says it should be a straight line, then that would be a reason to prefer the straight line despite its poorer fit. But if you had no basis for preferring a line with one slope over one with two, then one has little else to go on than the quality of fit. If those are similar then you have no basis for a decision.

    However if one model has an r^2 of 0.8 and another 0.99, one is inclined to favor the latter. For the period since 1850 neither a trendline nor a hockey stick in the above sense can achieve that.

    Moreover no model is likely to achieve that in the foreseeable future when short-term events are included, say any events of shorter duration than 15 years.

    Long-term climate modeling however holds out better prospects. A quantitative analysis of those prospects and associated uncertainties will be the subject of my presentation at the annual AGU meeting in December.

    • Vaughan,

      The periods 1910-1940 and 1970-2000 in the Hadcru 3 SH data set both have R^2 =0.6 and the period 1941 to 1969 had an R^2=0.07. So a cooling period having a low R^2 is not unprecedented in a warming world. I would think the pooh hits the fan when cooling has a high r^2 value.

      • The periods 1910-1940 and 1970-2000 in the Hadcru 3 SH data set both have R^2 =0.6

        You may be assuming that R^2 is only defined for linear fits, otherwise I’m not sure how to interpret your statement.

        In fact it is defined for any fit of a model M to data D, namely as
        R^2 = variance(M)/variance(D). There is no requirement that M be a straight line, otherwise modeling would be a relatively sterile art.

        Furthermore if M is a least-squares fit to D, then
        variance(D) = variance(M) + variance(D − M),
        whence variance(M)/variance(D) + variance(D − M)/variance(D) = 1. This relationship justifies speaking of variance(D − M)/variance(D) as the “unexplained variance” (relative to that of the data).

        All this remains true even if you take the data to be its own model, M = D. In practice one would only do this as a formal way of saying that the data is self-explanatory in some meaningful sense, or perhaps to say that you don’t have any model you take seriously, not even a trendline. For example when separating climate C into short term climate S and long term climate L, such that C = S + L, you might not be interested in modeling short term climate and hence take it as its own model, instead focusing on modeling just L in some way that explains L better than L explains itself.

        One must judge a model by its explanatory value as much as by its R^2 if not more, or you would always model data with itself because that gives an unbeatable R^2 = 1.

        Oddly enough the periods 1910-1940 and 1970-2000 contribute negligibly to the R^2 = 0.005 obtaining for my cycle-based model because those periods fit the AMO quite well.

    • A single straight line passes through all the global mean temperature (GMT) peaks, and the warming rate of this line (upper GMT boundary line) is 0.06 deg C per decade, which is equal to the global warming trend for the whole data as shown in the following graph.

      http://bit.ly/njBdvW

      As a result, the global warming rate is ONLY 0.06 deg C per decade.

      Permanent climate change is indicated if the upper GMT boundary line had been a curve with an increasing positive slope with increasing years, or the upper and lower GMT boundary lines had been diverging with increasing years. The data does not show ANY permanent climate change. It just shows a warming of 0.06 deg C per decade that existed before the mid- 20th century.

      • Correct.

        Additionally, the straight line trend is currently a lower value than it was from 1850 to any of the 1878, 1945 or 1998 peaks. If the cAGW theory was correct, the straight line trend from the start of ‘accurate measuring’ would have to increase.

      • Arfur

        Here is your statment above graphically:

        http://bit.ly/qGcD9M

        The upper GMT boundary line is a straight-line for 160 years. The GMT touches but not crosses this boundary line for long throughout the temperature record. However, the IPCC says there is further warming of 0.2 deg C per decade in the next two decades.

        Is that rational?

        How could something that has not happened in the last 160 years going to happen in the next twenty years?

      • Arfur Bryant

        Girma,

        I agree with you 100%. In the cAGW debate, if the starting premise is irrational, then we cannot expect any further supporting arguments to be rational either!

        The long term trend is appx 0.06 deg per decade.

        Regards,

    • Vaughan Pratt wrote: If you are willing to settle for a model of climate with an r^2 of 0.6 then you can find a wide range of such models that will prove anything you want.

      That is a smart way to put it.

      I have been writing that climate science mathematical models can have error rates as low as 3% and still not even get the sign of the “climate sensitivity” correct, even assuming that “climate sensitivity” is independent of temperature.

      I see that the AGU “fall” meeting is to be held in San Francisco in Dec. Next year’s Joint Statistical Meetings will be held in San Diego (July-Aug 2012). A quantitative analysis of incertainties in climate modeling might be welcomed there as well.

      • I have been writing that climate science mathematical models can have error rates as low as 3% and still not even get the sign of the “climate sensitivity” correct, even assuming that “climate sensitivity” is independent of temperature.

        I would say climate science is creeping very slowly towards a physically meaningful notion of climate sensitivity, without which climate modeling is a stab in the dark. I have my suggestions for how to speed up this process, hopefully by now others do too.

        It had never occurred to me to submit anything to a statistics meeting because all the statistics I’ve been doing is more trivial than the statistics I was taught in school half a century ago. However if there’s an applied section that is more interested in sound application of statistics to hot-button problems than in advances in statistics itself, I’d be up for that. I see February 1 is the deadline for contributed abstracts, and that Jarrett Barber is the contact for the section on Statistics and the Environment. Maybe I should bug him and/or Persi D. here for their thoughts.

  58. I would be interested in hearing from Dr. Curry how here presentation went, including questions and discussion. We disagree on the confidence deserved for the AR4 attribution of most global warming between 1950 and 2007 to anthropogenic ghgs – I see the “very likely” conclusion as justified while she sees more uncertainty in the interval – but her analysis of all the reasons beyond the evidence itself why such an attribution might be supported within climate science is insightful and should cause some introspection among scientists in the audience.

    On a separate note, some important scientific awards have just been announced, rewarding research that profoundly advances our understanding of the natural (and unnatural) world.

  59. Professor Curry,

    We’re all waiting in suspense, as Climategate is develops new leaks!

    Yesterday Quirin Schiermeier published WikiLeaks “news” in Nature magazine that UN’s “Clean Development Mechanism” (CDM) is but a fig leaf for wealth transfers from industrialized nations to poor developing nations:

    http://www.nature.com/news/2011/110928/full/477517a.html?WT.ec_id=NATURE-20110929

    http://www.powerlineblog.com/archives/2011/09/major-un-climate-program-“basically-a-farce”.php

    Thanks your help,
    Oliver K. Manuel
    Former NASA Principal
    Investigator for Apollo
    http://myprofile.cos.com/manuelo09

  60. The following was posted on Watts up with that unless they have chosen to ignore the real science that shows Why the greenhouse gas effect does not exist.
    If there are any real physicists especially ones with a background in quantum physics out there they know that when any gas absorbs radiation it does not cause the gas to “heat”. The work of Dr. Niels Bohr which resulted in his getting the Nobel Prize in physics in1922, knows that any claim of CO2 heating when it absorbs IR does not know what they are talking about.
    There is no question that CO2 and other IR absorbing gases (IRag) exist but there are many documented experiments that prove that they do not “heat” Anyone that claims that their experiment shows the heating of the gas by absorption is mistaking heating by conduction or convection for heating by absorption or because they are shining the heat lamp on the thermometer..
    The experiment shown in the Climate 101 fake video and the British heating of a gas in a bottle are example of “Confined space heating” aka The typical greenhouse effect- NOT THE Greenhouse Gas effect.

    • There is no question that CO2 and other IR absorbing gases (IRag) exist but there are many documented experiments that prove that they do not “heat”

      What is the concise agreement to explain the Venutian “atmosphere” and whey that gets so abnormally hot, way above the S-B law?

      • Ray Pierrehumbert has an excellent account at RealClimate, though true to form he digs deeply into the details so there’s a lot to wade through there. My shorter account below is based on Marov and Grinspoon’s extraordinarily comprehensive volume “The Planet Venus.”

        The short answer is that the greenhouse effect and lapse rate both determine the outcome. At the surface the temperature is around 740 K depending on latitude, and the emissivity is around 0.9, resulting in about 15 kW/m^2 of radiation being exchanged between the surface and the bottom of the atmosphere.

        The greenhouse effect confines essentially all of this radiation to the subcloud below 48 km, and the photons comprising the radiation are almost all trapped by the CO2 and form a radiation ocean in much the same way as water molecules form our oceans on Earth, but with much greater variation in mean free path due to some wavelengths being absorbed much more strongly than others. The pressure at the surface is on the order of 100 bars (Earth atmospheres), resulting in enough pressure-broadening that photons in the Venus troposphere have practically no chance of escaping to space.

        As on Earth the temperature drops off essentially linearly with altitude, and at essentially the same rate: theoretically 10-11 °C/km depending on temperature and pressure but in practice more like 8 °C/km. This rate holds for the first 60 km, including the first 12 km of cloud, for a net drop of 480 K at 60 km in round numbers, where the temperature is therefore around 740 – 480 = 260 K.

        The intensity of radiation at any given altitude follows the Stefan-Boltzmann law, falling off as the fourth power of temperature and hence of altitude. It drops from the intense 15000 W/m2 level at the surface to a freezingly cold 260 W/m2 at 260 K at 60 km. The next 8 km is more cloud then thinning out to haze, and the temperature drops another 100 K and the radiation falls below 50 W/m2. But most of this is trapped by the cloud and haze leaving very little to leak out to space. The stratosphere is warmer however, and at the top of the Venusian atmosphere 65 W/m2 of IR escapes to space.

        In short, almost all the radiation is trapped well below the subcloud on account of the greenhouse effect, with lapse rate and SB combining to govern the temperature and intensity of radiation at any given altitude.

        Around 10-20 W/m2 of direct sunlight creeps down to warm the surface and dimly illuminate it, just enough to maintain the radiation—the precise amount needed can be deduced from Ficke’s law for rate of diffusion, not that I’ve done the math. Without the sunlight the lapse rate would very gradually drop to zero as the warmer CO2 molecules slowly diffused up and the colder ones down, and the Venusian surface would eventually drop below freezing.

        Since Venus is considerably closer to the Sun than Earth, one would expect it to be above freezing, but Venus’s 0.7 albedo leaves only 30% of the insolation to keep it warm, in contrast to our 0.3 albedo which leaves 70% of warming sunlight for us. The upshot of this difference in albedo is that whereas our effective temperature is 254.3 K, Venus’s is a mere 184.2. Earth ends up radiating 3.6 times as much IR to space as Venus does.

      • The upshot of this difference in albedo is that whereas our effective temperature is 254.3 K, Venus’s is a mere 184.2.

        Yet you would burn up if you stood on Venus’s surface. I think this is what the commenter “cleanwater” is missing and does not understand, in that excessive CO2 can heat objects locally.

  61. Frankly, a broad and informed MIT audience would put Judith Curry in an awkward position regarding her gaps in knowledge, whether or not she acknowledges this. Accountability for her many errors and deficiencies (in understanding both science and policy issues) will not be suffered lightly by such an audience.

    Instead of continuing to raise intelligent questions about the IPCC process and uncertainty analysis, Judy has been dumbed down by her investment in the blogosphere, which she quite incorrectly perceives as a ‘key element’ in engagement with the public on climate change. If this thread and other threads are any indication, her self-described and narrowly neo-Conservative American audience shows an increase in fascist perspectives and comments.

    It’s quite disturbing. I don’t believe this was her end-of-career intention.

    At the same time — it was foreseeable, and she is accountable. It would be refreshing if she was held to a reasonable standard in terms of both current integrative understanding/ knowledge, and democracy issues.

    • “At the same time — it was foreseeable, and she is accountable. It would be refreshing if she was held to a reasonable standard in terms of both current integrative understanding/ knowledge, and democracy issues.”

      Yes, she should be silenced until reprogrammed.

      • Dallas,
        Ddi you get the part where this wackjob actually calls Curry a fascist?
        This is better than Air America. Martha is the answer to a really stupid, ignorant self-laothing question.

      • Hunter,
        Did you get the part where you don’t understand that “Curry’s audience” and “Curry” are not the same entity? Maybe you raise an interesting point; but I’d prefer to leave that open. ;-)

      • What would a fascist do with a dissident?

      • Perhaps we could bring back the stocks :>)

      • Big Red ‘D’ on the forehead.
        ===========

      • Judy should be silenced until she can use vapid phrases such as “current integrative (YUUUK) understanding/knowledge and democracy issues.

        You know what I loved about being in Lisbon with Judy and European Leftists? None of the real left spouted any of the nonsense I hear from the likes of Martha. I figure its because the real left had to actually face fascism. And they spot it in the american left.

      • Steven,
        So you decide the relevance of Europeans, Americans, and (all?) others who support democratic principles, for eveyrone. That is kind of interesting. How did you decide all this?

        Tell me, what exactly are your political beliefs? What is your view of social democracy as it relates to climate science/climate change action?

      • do you read. here is what I loved about Lisbon. none of the real left spouted any of the nonsense I hear from you. They were astounded to find out that the resistance to climate science was being led by the right. They thought it odd that the right would challenge authority and odder still that the left would defend it.

        These sentences have nothing whatsoever to do with me deciding anything about the relevance of anything. Nice try at changing the subject.

        My political beliefs are well known and weakly held. However, when it comes to climate change I have suggested policies that are diametrically opposed to my beliefs. Fancy that. Simply put, I am a pragmatist and would gladly toss any political belief I have out the window. If you want to understand my position read the book:

        https://secure.ametsoc.org/amsbookstore/viewProductInfo.cfm?productID=45

      • steven mosher
        re: “Judy should be silenced”
        Sounds like you seek to mimic Stalin, Mao, Pol Pot and their ilk in silencing everyone who does not agree with you. (There were “only” some 100 million killed by their own governments led by such tyrants in the 20th century.) Your statement is abhorrent.

        I encourage you to strongly uphold and defend the unalienable right to speak, especially of those you disagree with.

      • John Carpenter

        Really?….. Really??

      • being sarcastic david.. read the comment above.

      • steven
        There is a fine line between sarcasim and facisim.
        There is too much liberal facism around.
        Glad you enjoyed the time with Judith.

      • “she should be silenced until reprogrammed”
        Not at all. Her activity is part of the process of democracy (and reflection and criticism), on my view. However, your personal beliefs are concerning: why do you talk about this as a ‘silencing’ and ‘re-programming’ (of Judith Curry)? Are you at least aware, vaguely, that the world is bigger than this blog? Than you? Than me?

      • Sorry it was Fascist humor :)

      • What about the Rule of Law, Martha? Democracy isn’t the end all and be all. In fact, pure democracy was not implemented by the Founders of the US because it tends to run itself into the ground. Look at Europe.

    • Martha,
      Here it is, the triple witching hour- end of the week end of the month and end of the quarter, and like clockwork you show up to imply ignorance on the part of the MIT audience, Dr. Curry’s deficiencies and, in a massive dose of unintentional irony, tlaking about the dumbing down of others.
      Thank you, thank you, thank you , dear Martha for so dependably showing the true deliterious impacts of fanatical belief.
      Only you oculd possibly combine such wild examples of self-projection and vocabulary lacking wit. You are, in other words, the Janeane Garofalo of climate.
      http://www.foxbusiness.com/markets/2011/09/30/racist-rants-liberal/

    • Frankly, a ignorant audience would put Martha in an awkward position regarding her gaps in knowledge, whether or not she acknowledges this.

    • Instead of continuing to raise intelligent questions about the IPCC process and uncertainty analysis, Judy has been dumbed down by her investment in the blogosphere, which she quite incorrectly perceives as a ‘key element’ in engagement with the public on climate change.

      The blogosphere is probably no better or worse than anywhere else in trying to . make advancements in scientific understanding. People will talk past one another all the time, yet you try to extract whatever meager table-scraps of feedback that you can. Yet when it comes down to it, those table-scraps are better than nothing, and can occasionally reveal some innovative problem-solving approaches. YMMV but for just that, it may be worth it. It works for me because I have no other contact with work colleagues specifically talking about these issues.

    • Lol. Godwin’s Law.

  62. Martha wrote: Instead of continuing to raise intelligent questions about the IPCC process and uncertainty analysis, Judy has been dumbed down by her investment in the blogosphere, which she quite incorrectly perceives as a ‘key element’ in engagement with the public on climate change. If this thread and other threads are any indication, her self-described and narrowly neo-Conservative American audience shows an increase in fascist perspectives and comments.

    Hm.

    Some of the people who post here are quite knowledgeable on technical aspects of the AGW/Climate research and modeling. We don’t all leave our names, but some who do have faculty positions at prestigious universities, and regularly publish peer-reviewed papers. As to your use of the word “fascist”, the conservatives generally want less government control over everything; the “fascists” of yore arose out of labor movements, and their current representatives are “statists” (in Europe, including “greens”) and “liberals” (in the U.S.) who want more control.

    • Pregnancy termination (that other word may not get through the screen). Euthanasia. Homeland security. Marriage rights. Warrantless surveillance. Flag burning. Borders. Legalization of marijuana. The right to unionize. Access to voting. The right of American citizens to build a mosque. Broadcasting or other “morality” laws. Criminal sentencing.

      Seems to me that citizens of all stripes elect representatives that will enact policies that they favor. If a government enacts policies that a majority of citizens support, such as progressive taxation, then would that reflect citizen control or government control? Who is in control if politicians enact policies that only a minority of citizens – a minority that happens to be conservative – support? The government or the citizenry?

    • Hi Matt,

      “Some…” Yes, some… not most.

      For me, the interesting thing is that the majority of comments do not evidence either public engagement (awareness/action) or any expert opinion: at least, I don’t consider repetitive comments from a narrow support base of neo-Conservative participants (the majority of comment types over time) to be evidence of anything other than engagement with the political views of that narrow support base. I don’t consider it a dialogue with a diverse public, or a signficant number of other specialists. Posts that do not in any way accurately represent the views of other specialists, do not count as a ‘dialogue’.

      My use of the word ‘fascist’ to describe many of the comments is not a personal smear: I am using its political and historical meaning. However, I agree that Conservatives used to be anti-fascist (as well as anti-socialist).

      I think a question for any objective observer is why/how this blog gained signficance as part of the American Right blogosphere; and why there is an increase of fascist expression generall, in America (particularly by Conservatives, which as you suggest, makes little real sense). How all that has been applied to climate change denial or ‘skepticism’, is another layer of questioning. There’s alot of stuff e.g. increased poverty and unemployment, insecurity, changing global relations, celebrity-type media, that may be contributing to all this.

      Nice speaking with you. Take care.

      • As an avowed leftist, I take issue with your categorizing free thinking as fascist, and exclusive to the American Right (blogosphere). I think this blog’s significance can be tied to how it raises questions that others (in the MSM and climate science community) seem to think are unworthy of exploring.

  63. Quite a bit of upset about Martha’s use of “facist.”

    While I agree that it is uncalled for, somehow I don’t think it is the first time in these here Climate Etc., threads that the word has been bandied about. Or similar types of references to “statists” or eugenicists.

    I don’t recall similar outrage with the past occurrences.

    Geez, I suppose there might be something different about the context of Martha’s usage, but I just can’t quite put my finger on it.

    • I don’t doubt it is very hard for you to understand. It’s the irony of the authoritarian calling the anti-authoritarians “fascist”.

    • ‘Fasces’, a bundle of sticks to beat one with, and don’t you forget it.
      ============

    • Joshua, Now you have to admit Martha set herself up for that implies more rigorous standards for Judith’s blog behavior. :)

      • I’m not defending Martha’s rhetoric. I find it unfortunate at times.

        Just as I find unfortunate the accusations of fascism, and other over-the-top rhetoric we find from the other side of the climate debate in these here threads.

        What I am noting is the lack of “symmetry” in the denouncement of such rhetoric, particularly given the proportions in which it can be seen coming from the different sides of the debate.

      • Well, I can see that, but most of the others are no fun to pick on, some are really out there (not that Martha is not). :) Besides, Fascism is kinda fun, It started as a bipartisan effort to unite a country, in order to stimulate national pride, under an authoritarian leadership. Kinda slipped of course a touch. Fascists are bad, they just do bad things :)

      • er.. Aren’t bad, just do bad things. My key board is a Fascist.

    • I’d send her out for sensitivity training. I think my human rights have been violated

  64. Dr Curry,

    Why monster? An exaggeration like all AGW predictions?

  65. “Quite a bit of upset about Martha’s use of “facist.””

    What is a “facist”? Someone with a cist on their face?:)

  66. In Douglas Adams’ book “The Hitchhiker’s Guide to the Galaxy’ the Philosophers state
    “We demand rigidly defined areas of doubt and uncertainty.”
    To that we can now add
    “We demand that these rigidly defined areas of doubt and uncertainty be quantified.”
    That’s what 20 years in pharmacovigilance does to one’s brain!

    • “We demand that these rigidly defined areas of doubt and uncertainty be quantified.”
      That’s what 20 years in pharmacovigilance does to one’s brain!

      For aleatory uncertainty, no problem as it can often be quantified exactly.
      If the aleatory uncertainty quantified by the Fermi-Dirac statistics of the electrons and holes running through transistors ceased to exist, the computer that you are typing on would stop working. No wonder Jaynes called probability “The Logic of Science”.

  67. “Dr Curry,
    Why monster? An exaggeration like all AGW predictions?”

    Check out draft of her lecture above..

    • Have to agree – the “monster” tag has always seemed gratuitous, and a sub-Orwellian form of special pleading – “my catastrophe theory is not only more important than your catastrophe theory, it’s CATEGORICALLY more important”. Uncertainty is best seen as just that – uncertainty.

  68. I referred to a ‘narrowly neo-Conservative American audience’ that ‘shows an increase in fascist perspectives and comments’.

    I am not speaking rhetorically, I am actually describing fascist characteristics. It need not mean exactly what it meant in Nazi Germany or Latin American dictatorships, to be descriptive; still, I don’t use the term lightly. At all.

    What do I see, here? Well, I see an increase in what I see elsewhere on the Right: nationalism to the point of extreme jingoism, attitudes that human rights are only for some, and support for the most powerful people to frame issues and define agendas, etc., for all.

    I agree with whoever suggested irony, since it is incredibly ironic to me, and but more importantly frightening, to see such expressions among people who used to be anti-fascist and who think they are behaving as anti-authoritarians.

    Dissent from Right-wing ideas and intellectual and scientific critique of Judiith Curry’s perceptions is barely tolerated on this site.

    Overall, call all of this together, whatever you want. Contrary to several responses, I chose the word that I chose to describe it, very carefully; and with an understanding of what it means, and why it would be a controversial word on this site.

    • John Carpenter

      Martha,

      This use of the word ‘fascist’ is not controversial here, what is controversial is how you have re-defined what ‘fascist’ means and think everyone will merrily go along. The word ‘fascist’ is one of those terms that gets tossed out by intellectuals so often that it really has no useful meaning any more. When words like ‘fascist’ are continually re-defined and misused by users whose intentions are to exaggerate situations, they simply lose their meaning. It’s a boring term now. You may have pondered long and hard about using the term, but it was really unnecessary because the word has long lost any punch it once had… your misuse has simply driven another spike into it’s demise as a useful linguistic term.

      Thanks a lot

    • Martha

      As a person who is not Republican, right wing or generally conservative, I find your comments as highly prejudiced regarding people who comment here or who generally disagree with the conclusions of the IPCC. I guess you make them only to get attention.

      I fully accept the basic physics, disagree on the conclusions regarding the rate of warming, do not think we fully understand the impact of the oceans, the changes in the Sun’s impact and perhaps most importantly also do not believe that the climate models used to draw the conclusions written in the IPCC’s reports have produced sufficient results to warrant the conclusions written.

      Ok, as a poster here, who has pretty good technical background in physics and computer modeling, are you claiming I am exhibiting Nazi like behavior?

      Which of my conclusions do you believe are incorrect and why. I would like to learn by the exchange.

      Are you really sure of the rate of warming?

      Are the potential harms written about in AR4 something that you believe are really likely to happen? Have the models used to reach these conclusions demonstrated their accuracy based upon other accurate predictions so that you believe the predictions to be very likely to happen? Really??

      • Rob –

        I am regularly told at this blog that I am (paraphrasing) a “warmist” (although I don’t believe that I’ve ever stated what my precise belief re: AGW is), eco-zealot, who is is a cult follower of the religion of AGW, and whose main interest is in pursuing statists/socialist aims to destroy capitalism and impose neo-Luddite energy schemes with indifference to the starvation of millions that will result.

        Do you find such characterizations to be highly prejudiced? If not, why not?

      • Joshua
        I would reply regarding specific comments someone made to or about you, but not a broad generalization of the comments.

        If I were to broadly generalize comments regarding AGW, I find that those who believe that significant actions need to be immediately taken to reduce CO2 emissions to be unwilling to honestly and fully address the issues I have previously written about.

        What I generally read is that I:
        A) must accept their scientific conclusions regarding the likely rate of any warming and:
        B) should accept the outputs of the climate models that were the basis of their conclusions and that:
        C) I should necessarily accept their conclusions when they interrupt the results from these climate models and “conclude” a warmer world will result in a net overall harm to humanity, and that I:
        D) Must accept their conclusions that if my nation were to implement the action plans they have outlined that the world is likely to have a much better future and that their proposed actions are the correct for society.

        If I fail to accept the data used to form their conclusions, or the models, or the conclusions, I am subject to be called a “denier” or anti-science.

        IMO- the thought processes used by those strongly advocating the IPCC’s proposed action plans seem very similar to those with a strong belief in their religion. I am not saying that their belief is necessarily wrong. I am saying I have not been shown enough evidence to accept their conclusion.

      • Rob –

        I think that your description is entirely fair – with reference to some of the participants in the debate. Specifically, I think that there is a fairly common phenomenon where some unfairly characterize all “skepticism,” as “denial.”

        By the same token, I have often seen in these threads and others of “skeptical” websites a tendency among some to unfairly characterize all of those who are “convinced,” or even someone like myself who is not necessarily “convinced” but is not willing to categorically reject the notion that it is 90% likely that more than 50% of recent anomalous warming is due to anthropogenic CO2 emissions. The characterizations run quite a gamut – from socialist, to eco-zealot, to statist, to worshiper of a cult religions, etc.

        I would reply regarding specific comments someone made to or about you, but not a broad generalization of the comments.

        I respect your reluctance to speak more generally while being open to replying to specific comments – but I don’t really want to get into quoting specific comments; first, I’m not sure it’s worth the effort, and second, it would obscure my main point which is reference to a more general phenomenon.

        I would just ask that in the future, as you rightly object to unfair characterizations in the comments of someone like Martha, or perhaps someone like myself, you also look at the comments of hunter, or Wagathon, or Gary, or cwon, or Bruce, or Jim Owen, or mannacker, or randomengineer, or any other number of Climate Etc. commenters with a similar scrutiny with respect to unfair characterizations.

      • btw, Rob –

        I’d just like to point out this comment in case you would like to respond but missed it earlier. I’d be curious to read your response.

        http://judithcurry.com/2011/09/28/uncertainty-monster-visits-mit/#comment-117114

    • What do I see, here? Well, I see an increase in what I see elsewhere on the Right: nationalism to the point of extreme jingoism, attitudes that human rights are only for some, and support for the most powerful people to frame issues and define agendas, etc., for all.

      1. nationalism? no Martha, nationalism would be something like this.
      the USA should only use US science
      2. Human rights are only for some?
      No Martha, the people making videos about blowing their
      opponents up would be you. The people trying
      to deny the poor developing nations cheap coal would be
      you.
      3. Who frames the issues?

      The issue was framed when the IPCC was formed. Global
      action is required. That effectively cut the legs out from
      anybody who believes in local action first and building
      grass roots support. The current power structure is the
      one that broke FOIA laws. wrap your fascist head around that.
      The current power structure is the one that refuses to adopt
      powerful conflict of interest rules. the current power structure
      is the one that disinvites people to speak. The current power
      structure is the one that told Judith she should not have
      McIntyre come to speak. the current power structure has declared
      that the debate is over. When the debate is over, what does the power
      structure do to people who keep talking.. see the video I reference
      in point #2.

    • I never saw any of your posts before. The first I saw was at worst debatable. But now, fwiw, I think you are blathering nonsense.

  69. you see “nationalism” on this site?

    • that was in response to Martha.

    • What I see and what I have experienced on this site is a predominance of discussion that caters to reactionary nationalist attitudes, especially in relation to foreign policy on climate change.

      Your experience?

      • A variety of different perspectives have been written about here and have been accepted or generally rejected based on their ability to defend their position. Some of these ideas have had less merit than others but for you to write comparisons to the Nazi party is inappropriate.

        I have written here about individual nations to taking positions regarding acceptance of climate change policies in their own self interest. That is quite different that the position of the German Nazi party.

      • you dont get it. In Martha’s world if you talk about your nations interest that is being a nazi. Unless you live in a developing country or a country that will be under water, then its ok to talk about your interests. In Martha’s world if you talk about preparing for the coming troubles with better water management, better management of coastal development, moving quickly to nuclear, if you constrain your vision and practice to the things you can actually control, then you are a Nazi. You are only not a Nazi if you agree with Martha. You prove you are not a Nazi by agreeing that an impossible global treaty is the best course of action. You prove you are not a nazi by forgetting that decades of trying to get this treaty have resulted in utter failure.

      • You have to remember that according to Martha, ideology began with Karl Marx. With that as your starting point, everybody to the right of Fidel Castro is a reactionary, fascist, racist tool of the running dog capitalist conspiracy. You know, a skeptic.

      • I guess we have made very different observations of the same situation. It’s interesting how that can happen.

        “for you to write comparisons to the Nazi party is inappropriate”
        I didn’t. I agree that would be inappropriate – because it is politically and historically incorrect, and insensitive to millions of victims. But I think you know that a comment stating there are increasingly fascist characteristics in neo-Conservatism (and the American Right blogosphere) especially re. climate change science and foreign policy is one statement, and what you are attributing to me is another. Or do you?

        That’s all for now, Rob. Maybe we can try to discuss this again some other time.

      • Some comments are provocative, reactionary or critical but I find the cAGW believers more nationalist than the nonbelievers on this blog. Also the most extreme believers all seem to be from the US on this blog.

      • That’s interesting. Thanks.

      • What nationalism do you see from “cAGW believers” on this blog? Can you give some examples?

      • By jingo! I think we were just insulted!

  70. I don’t get why you folks keep engaging the woman. Want her to go away?
    Ignore her. I sure do.

  71. Judith, I’ve read your presentation, and have one comment.
    You write

    “Uncertainty should be expressed using the most precise means that can
    be justified, but unjustified more precise means should not be used.”

    Given the large number of hypothetical components used to build the over-arching hypothesis of CAGW, I would have liked to see something to the effect of:

    “As a principle, no conclusion may have less uncertainty than the most uncertain of the hypotheses used to form it.”

    Break a leg.

  72. Joshua writes in a comment above “…I don’t believe that I’ve ever stated what my precise belief re: AGW is.”

    This may be the most honest, revealing comment I have seen Joshua post here…ever.

    The single most prolific commenter on this blog (a blog dedicated to welcoming all perspectives, and debating any and all of the various scientific and political issues in one of the central public policy debates of our time) has never stated what his “precise belief” is regarding anthropogenic global warming. What a profile in courage.

    A nice confirmation that Joshua simply criticizes the positions others take, answers questions with questions, and complains about the bias of the gracious hostess of this blog (who virtually never responds in kind or censors his innumerable, repetitive comments).

    Talk about a disproportionate signal to noise ratio…not even Michael Mann could massage meaningful content from this “data stream.”

  73. Joachim Seifert

    Hi, Pekka, as you write, there is short term variability and long term variability……how significant are both variabilities, if one strong input parameter is missing in all models?
    This is the case in climate science….. totally missing is “libration forcing”
    (see wikipedia:’Libration’ – the Earth does the same in its orbit as the Moon)
    All models exclude parameters of the Earth’s orbit….., the IPCC keeps
    them “Invariant”…. and this is the smelling dog….!
    JSei.

    • Science is not done with random fitting with 100 parameters. Having everything in a statistical analysis gives totally useless results. To get anything useful, it’s necessary to make some estimation on, what might be important and what’s almost certainly insignificant. Then the latter variables must be left out. They can be introduced again, if the arguments that lead to their exclusion are shown to be lacking.

      Orbital issues are important on extremely long time scales, but belong to those that can safely be excluded from most analyses.

  74. Joachim Seifert

    Hi, Vaughan,
    as I just wrote to Pekka:
    How can climate models claim to have a good percentage of accuracy,
    while a crucial input parameter has been left out completely?
    Let’s say, 99 input parameters were used in all models, but the parameter number 100, which is highly significant, is not included. Result: The 99-model gives a 95% – probability (“very likely – according to IPCC) and we waste our time jiggling 10 or 20% of it down…., even JC, regrettably….
    The plain truth is, that 99-parameter-models have nothing more than
    0% accuracy…… unless you can pull some percentages out of your hat with
    screwed statistics…..
    JSei

    • The plain truth is, that 99-parameter-models have nothing more than
      0% accuracy.

      I’d say we’re in pretty good agreement there. But I’m not sure why you addressed me specifically. Had you formed the impression I held the opposite view?

  75. Joachim Seifert

    Response to Pekka:
    Too bad, I have hoped, you could go in-depth to my reply and avoid
    on-the-surface bla-bla…. Let’s then call ‘parameters’ with your preferred word ‘Variables’. How is it then when a major ‘variable’ is missing? And since
    variables differ in their hierarchy, when a major hierarchically bottom variable is missing?
    Second, your orbital response does not concern what I am talking about: “The Libration forcing of the orbit.”
    This is different to your point, which is based on AR4-wg1-chapters 2,6 and 9, and concerns only ‘long-term elliptical Milankovitch changes’ not found “on a less than millenium scale” – which is correct but which is not my point with the missing crucial variable……
    We should keep away from surface bla-bla. Please see the Wikipedia “Libration” definition, an animated picture is also shown for better imagination. Your elliptic Milankovitch response is completely off the track…..
    JSei.

    • Tell one reason, why the libration would be of any significance.

      I mentioned the very long time scales, because there are reasons to expect some significant effect on those. I haven’t seen any reason to expect anything of significance from libration.

  76. Judy’s presentation showed her own journey from agreeing with the IPCC attribution statement:

    “Most of the observed increase in global average temperatures since the mid-20th century is very likely [>90%] due to the observed increase in anthropogenic greenhouse gas concentrations.”

    to no longer being able to agree with it because of the uncertainties she felt clouded the ability to use such confidence levels as [>90%], and also the ambiguous qualifier “Most” (How much is “Most”? >50%? But less than 80%?). Please let me know if the value of “Most” has been hashed out and determined elsewhere.

    It seems to me, the following attribution statement might not be in conflict with the IPCC’s attribution statement above:

    “Much of the observed increase in global average temperatures since the mid-20th century is very likely [>90%] due to natural variability in the earth’s climate system.”

    If we hold these two (or similar) attribution statements together, do they not begin to illustrate the inherent uncertainties involved?

    • Matthew – “Most” is generally thought to mean more than half. Judy doesn’t believe that the evidence supports the AR4 claim that most warming in the 1950-2007 interval is >90% likely to be due to anthropogenic greenhouse gases. I disagree with her on that point, based on a careful examination of the evidence surrounding the relevant anthropogenic and natural factors as well as the accompanying uncertainties. That doesn’t mean I’m right, but I do take issue with her inference that my confidence in the attribution statement reflects psychological processes beyond an objective appraisal of the evidence based on some knowledge of the subject.

      I also find that because of the interval chosen, it is hard to justify a conclusion that “much” of the warming is due to natural variability of an unforced nature (i.e., internal climate fluctuations). With solar forcing included as a natural phenomenon, “much” might be justified, but I’m still not sure.

      According to her description, questions following her talk didn’t dwell on these technical issues, but focused more on the IPCC and other aspects of how climate science conducts itself. It’s appropriate to address those issues, but the technical questions still remain important if one is to judge whether the IPCC or other groups of scientists are drawing proper conclusions. I don’t think that’s always the case, but I do think they got this particular attribution right.

  77. Joachim Seifert

    Hi, Pekka,
    orbital libration forcing occurs on a less than 1 millenium time span.
    Leaving it unnoticed, hidden under the table:
    1. Allows “robbing” of RF from the orbit and “artificially increasing” the
    forcing values of atmospherical sources (emissions, CO2…), as the
    IPCC does…..
    2. The hierarchy of the energy flow from Sun to Earth has to be
    correct: First comes: Changes in energy output on the Sun, second:
    changes in orbital libration ( contributes significantly to changes in daily
    distances Earth – Sun), third comes Albedo (energy loss into space)
    and at the VERY LAST:
    and fourth, changes in atmospherical sources.
    This means: Atmospherical changes are at the end of the totem pool
    and are at best the remainder in total forcing, after accounting
    solar energy from the first to the third step.
    3. Putting energy accounting and forcing calculations into the
    troposphere (as the majority of climate papers) will lead to false climate
    prediction models, with
    false global temp increase predictions (see: false TAR and SRES since
    2001) whereas, from this very year on global temps GMT and OHC ocean
    heat content remain flat…..

    4. Only a calculation of orbital libration produced an exact 21 Cty
    temp. forcecast…..
    JSei