Uncertainty Monster paper in press

by Judith Curry

My paper “Climate Science and the Uncertainty Monster” is in press at the Bulletin of the American Meteorological Society.

Climate Science and the Uncertainty Monster

Judith A. Curry and Peter J. Webster

Abstract.  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 paper 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. An uncertainty lexicon is provided that describes the natures and levels of uncertainty and ways of representing and reasoning about uncertainty. Uncertainty of climate models is interpreted in the context of model inadequacy, uncertainty in model parameter values, and initial condition uncertainty. We examine the challenges of building confidence in climate models and in particular, the issue of confidence in simulations of the 21st century climate. 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.

The paper is online [here].

For those of you who have followed my previous uncertainty threads, there isn’t any new material here, but the significance is in its publication in a refereed journal so that it will reach the audience that we hope will be most influenced by this.

This paper is pretty much guaranteed to generate controversy.  We anticipated this at the time this was submitted, and requested that the editors NOT select any reviewers participating as lead authors in the AR4 or AR5.  Apparently our request was honored, and we received two very useful and constructive reviews on the paper.

Not suprisingly, a Comment on the paper has already been submitted, focused on Section 4 of the paper regarding attribution.  I’m providing the text of the reply to the Comment that we have submitted, preserving the anonymity of Comment.

Reply to XXX’s Comment on “Climate Science and the Uncertainty Monster”

Judith A. Curry and P.J. Webster

We would like to thank the authors of the Comment for their interest in our paper. The authors are correct that since the Third Assessment Report, the IPCC has placed a high priority on communicating uncertainty, and perhaps their methods have been effective in communicating with the public.  However, communicating uncertainty is a very different endeavor from actually characterizing and understanding uncertainty, an effort in which we feel the IPCC falls short, especially from the perspective of scientists outside the IPCC process (climate scientists as well as scientists from other technical fields).

Curry and Webster (2011) raise the issue of how the IPCC has actually undertaken to investigate and judge uncertainty.  XXX’s comments focus on section 4  Uncertainty in attribution of climate change of our paper (Curry and Webster, 2011), which addresses the IPCC AR4 conclusion regarding attribution:

“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.”

The text in the IPCC AR4 (chapter 9) referenced by XXX describes general issues and methodology for investigating uncertainty on the topic of attribution, including listing uncertainty locations. In preparing our original manuscript, we read these passages and the cited references numerous times.  Listing a large number of uncertainty locations, and then coming up with a “very likely” likelihood statement using expert judgment in the context of a consensus building approach, is at the heart of our concern regarding the IPCC’s treatment of uncertainty.

XXX’s statement “The remaining uncertainty in our estimates of internal climate variability is discussed as one of the reasons the overall assessment has larger uncertainty than individual studies.” Translating this uncertainty in internal climate variability (among the many other sources of uncertainty) into a “very likely” likelihood assessment is exactly what was not transparent in their assessment. 

We most definitely “do not appreciate the level of rigour with which physically plausible non-greenhouse gas explanations of the recent climate change are explored.”  Specifically with regards to solar forcing, a rigorous uncertainty assessment would have included a systematic exploration of individual model sensitivity to different solar forcing datasets and the associated range of uncertainty.  Further, some account for known unknowns associated with indirect solar effects should be included in any assessment of confidence or likelihood.  Chapter 2 in the AR4 WG1 report characterizes the uncertainty associated with aerosol direct forcing as medium to low, and the uncertainty associated with the aerosol indirect effect on cloud albedo is characterized as low.  This characterization of aerosol forcing does not even include most of the known aerosol indirect forcing mechanisms, which adds even greater uncertainty to the aerosol forcing. With regards to aerosol forcing, a rigorous uncertainty assessment would have included sensitivity simulations of individual models to a range of aerosol forcing (which is associated with low to medium confidence levels) and some account for the absence of known mechanisms of aerosol indirect forcing.

Our overall concerns about the IPCC AR4 attribution statement and uncertainty analysis are best illustrated in the context of the recent publication by Gent et al. (2011), showing simulations of the 20th century climate of the NCAR Community Climate System Model Version 4.  Figure 1 [the link downloads the file] compares the results of the CCSM3 (used in the AR4) with the CCSM4 simulations (for the AR5).  In spite of using a better model and better forcing data for the CCSM4 simulations, the CCSM4 simulations show that after 1970, the simulated surface temperature increases faster than the data, so that by 2005 the model anomaly is 0.4oC larger than the observed anomaly. By contrast, the CCSM3 simulations show very good agreement with the surface temperature data.  The critical difference is that the CCSM4 model was tuned for the pre-industrial period and used accepted best estimates of the forcing data, whereas the CCSM3 model was tuned to the 20th century observations and each modeling group was permitted to select their preferred forcing data sets.  The contrast between the CCSM3 and CCSM4 simulations illustrate the bootstrapped plausibility of climate model simulations that influenced the AR4 attribution assessment.

The heart of our argument is that the broader scientific and other technical communities (beyond the field of climate science) have higher expectations for understanding and characterizing uncertainty than has been portrayed thus far by the IPCC. We hope that the forthcoming IPCC AR5 will improve its exploration and characterization of uncertainty, with the actual communication of uncertainty to policy makers following from a detailed and transparent assessment of the uncertainties written for a technical audience.

While looking at the other early online papers, I spotted this one:

A weather and climate enterprise strategy for generating and communicating forecast uncertainty information

Paul A. Hirschberg, Elliot Abrams, Andrea Bleistein, William Bua, Luca Delle Monache, Thomas W. Dulong, John E. Gaynor, Bob Glahn, Thomas M. Hamill, James A. Hansen, Douglas C. Hilderbrand, Ross N. Hoffman, Betty Hearn Morrow, Brenda Philips, John Sokich, and Neil Stuart

Abstract.  The American Meteorological Society (AMS) Weather and Climate Enterprise Strategic Implementation Plan for Generating and Communicating Forecast Uncertainty (Plan) is summarized. The Plan (available on the AMS Web site at http://bit.ly/gbkcc1) is based on, and intended to provide a foundation for implementing, recent recommendations regarding forecast uncertainty by the National Research Council (NRC), AMS, and World Meteorological Organization. It defines a vision, strategic goals, roles and responsibilities, and an implementation roadmap to guide the weather and climate enterprise (Enterprise) toward routinely providing the nation with comprehensive, skillful, reliable, and useful information about the uncertainty of weather, water, and climate (hydrometeorological) forecasts. Examples are provided describing how hydrometeorological forecast uncertainty information can improve decisions and outcomes in various socioeconomic areas. The implementation roadmap defines objectives and tasks that the four sectors comprising the Enterprise (i.e., government, industry, academia, and nongovernmental organizations) should work on in partnership to meet four key, interrelated strategic goals: (1) Understand social and physical science aspects of forecast uncertainty; (2) Communicate forecast uncertainty information effectively and collaborate with users to assist them in their decision-making; (3) Generate forecast uncertainty data, products, services, and information; and (4) Enable research, development, and operations with necessary information technology and other infrastructure. The Plan endorses the NRC recommendation that the National Oceanic and Atmospheric Administration and in particular, the National Weather Service, should take the lead in motivating and organizing Enterprise resources and expertise in order to reach the Plan’s vision and goals, and shift the nation successfully to a greater understanding and use of forecast uncertainty in decision making.

Link to online paper [here].

JC comments.  The reaction to the uncertainty monster paper promises to be interesting.  The community on the weather side of the house (reflected by the Hirschberg et al. paper) seems to understand the issues.  Such efforts should help tame the weather and seasonal climate uncertainty monster.   As for the uncertainty monster surrounding the climate change issue, I can only hope this paper and the forthcoming issue in Climatic Change on framing and communicating uncertainty for the IPCC will help, and pave the way for the IPCC to do a better job of characterizing and assessing uncertainty.

289 responses to “Uncertainty Monster paper in press

  1. So the paper hasn’t even been published, and you already have a comment in hand? Isn’t the discussion of a paper supposed to happen AFTER it has been published? Assuming that both paper and comment will be published at the same time, why should the original work have to compete with a secondary comment at the time of publication? It sounds like they are publishing your paper, only to allow your critics an equal platform at the same time.

    • Actually i was surprised at first also. But the AMS posts its in press papers online as soon as they are accepted, so that people can comment on them. The paper was posted Aug 8, will be published in the Dec issue of BAMS, presumably with the Comment and the Reply (other comments are likely, which may be published later).

      • Posted AUGUST 8?

      • I deeply appreciate your efforts to expose the “Uncertainty Monster.”

        The “Uncertainty Monster” of 2011 may be the offspring from the forty (40) year gestation period of a Chinese Dragon, fertilized in Peking on 9-11 July 1971:

        http://www.gwu.edu/~nsarchiv/NSAEBB/NSAEBB66/ch-40.pdf

        The pregnancy was hidden from the public for more than thirty (>30) years before being cited as footnote #4 to government declassified documents about President Nixon’s trip to China on 21-28 Feb 1972:

        http://www.gwu.edu/~nsarchiv/NSAEBB/NSAEBB106/index.htm

        President Nixon gave the first public hint in his announcement on 5 Jan 1972 that the Apollo program would be dismantled:

        http://claudelafleur.qc.ca/Nomoredreams.html

        There was gossip at the Lunar Science Conference on 10-13 Jan 1972 that US President Nixon and other world leaders might sign a world peace treaty while orbiting Earth instead of pursing the space race.

        President Nixon visited USSR leaders in Moscow on 22-29 May 1972. The seemingly far-fetched idea of world leaders signing a peace treaty while orbiting Earth never materialized.

  2. Dr. Curry:
    Congratulations!

    Roy Weiler

    • Hiding uncertainty shows an unwillingness to admit that we are powerless over Nature (Cause and Effect, Coincidence, God). That seems to be the root of many of society’s problems today.

      The worldwide sense of impending doom may not be relieved unless we find a peaceful way to restore:

      – Integrity to government science, and
      – Control over government to citizens.

      With kind regards,
      Oliver K. Manuel
      Former NASA Principal
      Investigator for Apollo

  3. I think one of the key themes that needs to get communicated to the general public comes out of a statement in the comment, my highlighting.

    ‘Listing a large number of uncertainty locations, and then coming up with a “very likely” likelihood statement using expert judgment in the context of a consensus building approach, is at the heart of our concern regarding the IPCC’s treatment of uncertainty.

    Expert judgment is something that most people do not think of when the word science comes to mind. Most people, I think, see a man or woman in a lab coat doing research that ‘tells’ him/her the answer to the question at hand.

    In the vast majority of instances, however, especially at the forefront of scientific inquiry, researchers are forced to make as good a guess as they can. In the case of something like the IPCC, I think having many, many heads working on the problem helps in this way because you have a pretty filter for your guesses.

    But, to a certain extent, with poor conditioned data, like most climate data older than a week decades, guesses are pretty much all we have.

    Maybe we could start a new series of posts called ‘The Judgement Monster’. I’m sure that would go over even worse with some people than this series…

    • Maxwell said:

      “I think having many, many heads working on the problem helps in this way because you have a pretty (sic) filter for your guesses.”

      The logical basis for this statement is well founded in practice for many situations. However, I am firmly of the view that “too many cooks spoil the broth” in cases where a paradigm shift is being contemplated.

      For a paradigm shift to occur it usually comes about because an individual has challenged the way most people think about what is happening around them.

      In my experience, the more people who have input into a decision of importance, the less effective the decision-making process becomes.

      I do not know of worthwhile scientific progress being made by any group of individuals. There is more usually some form of regression taking place where inevitable compromises are made by individuals in order to achieve results in a group situation.

      • see the polyclimate thread. that was a good thread that didn’t seem to go anywhere, i will reintroduce it at some point
        http://judithcurry.com/2011/04/22/polyclimate/

      • The idea of a shared praxis is interesting but I wonder that this would be too much to ask of a diverse group of individuals who seem to have widely differing agendas and abilities.

        For example, is it possible for all to agree that the study of weather conditions and climate trends must necessarily be done on the basis that the system as a whole must be considered as non-ergodic by nature and not capable of prediction?

        If this were to be agreed, then all existing climate models and their predictions must be discarded and the group will need to start all over again.

        Based on what I have read to date on the climate issue in this and several other blogs, I rather doubt that such a praxis would be reached.

  4. J.C. writes: “As for the uncertainty monster surrounding the climate change issue, I can only hope this paper and the forthcoming issue in Climatic Change on framing and communicating uncertainty for the IPCC will help, and pave the way for the IPCC to do a better job of characterizing and assessing uncertainty.”

    Kudos on your paper Dr. C… which seems to me goes to the very heart of the discussion. Or at least, the heart of the discussion we should be having. The only deniers in this debate are the warmists who refuse to admit the science is as far from settled (to say the least)… Let’s hope the paper causes a great hue and cry from the alarmists as that’s the best way to ensure the paper gets the attention it deserves…

    • I’m sure there is someone who denies global warming because they heard about it one day, commenced to read the research and reports, then after doing so, weighed the pro climate change argument and con climate change argument, and judged the con climate change argument to be more compelling — no need to change behaviors, keep burning fossil fuels. But whoever they are I have not run across them.

      But, then I don’t know of any creationists who arrived at their position like that either. All the creationists I’ve met simply don’t like evolution so they say it’s just a “theory” and the science is far from settled, too.

      The scientists and researchers I’ve spoken with are not “warmists who refuse to admit the science is as far from settled” but are genuinely interested in getting to the bottom of what is and what isn’t. We’re all human beings so, granted, there is some bias. But these are professional scientists who don’t engage in cheap shot phraseology like, “The only deniers in this debate are the warmists…”

      To deny global warming because you gave all the evidence a fair hearing is fine. Then say that. But I’m suspicious of people who are overly passionate, even bitter sounding, and are against other people rather than being against a position. I don’t care who you are, the moment it becomes personal is the moment you’re not really interested in the truth. That’s at the heart of the discussion, too.

      • We’d all like to hear more from those professional scientists who don’t engage in cheap shot phraseology. It seems they don’t make the papers too much though, or else the editors and their readers are more interested in conflict than reason. One presumes that pokerguy was referring to the likes of the much-quoted, and usually very offensive, Trenberth, Gleik, Hansen, Mann, Schmidt etc. when he spoke about people who refuse to admit the science is far from settled. Well unfortunately the cheap shots fly thick and fast from that cabal. And yes surely, you’d hope, these must be outliers in the climate science community but outliers such as these seem to dominate both the media and the IPCC process alas. This is what McI calls the silence of the lambs.

      • Actually Coaag, what you described is pretty much how I came about by skeptical position. I researched AGW and found that science backing it to be extremely weak. Basically it came from a group of scientists who using the models at the time couldn’t account for the increase in temperatures that we saw in a 20 year period (late 70s to late 90s) from natural sources. So they declared it must be a function of what man has done. CO2 had increased a lot so that must be it.

        Now the fact of the matter was the models back then weren’t accurate (they still aren’t). The climate system is a chaotic system and we are only beginning to really understand it. To do what the warmists want to do based on such a weak premise would be the equivalent of throwing a virgin into a volcano to sooth the volcano gods.

      • Which side obfuscates their political inclinations more? Pro-AGW or anti-AGW?

        People who can’t address the question are the same people who will tell you the NY Times is a middle of the road newspaper. It’s all part of why the debate is dishonest as it exists and how radical so much of the core AGW support really is but it’s a taboo to talk about it. Another form of poltical correctness I refuse to observe here or anywhere. Add to that the level of sanctimony of the left’s establishment attitude and you can see why these boards are angry and circular.

    • To add, there is so much gray area in what to make of the evidence that to pigeon-hole others as warmists is essentially labeling them as extremists. That’s the kind of label that attempts to negate whatever they have to say even if the label is just an invention.

      • Hmmm, “to pigeon-hole others as warmist is essentially labeling them as extremist.” I’m grateful that those who believe in AGW don’t do that to people who don’t agree with them.

  5. I remember this and some responses thereafter (‘heretic’,etc)
    http://bishophill.squarespace.com/blog/2010/6/28/josh-25-jude-of-arc.html

    I do hope the broader scientific community pays attention to this and gives a positive response, and some good professional backup to the inevitable negative responses ;)

    http://www.cartoonsbyjosh.com/download/Right_of_reply.jpg
    http://www.cartoonsbyjosh.com/download/Right_of_reply.jpg

  6. Hi Judy –

    Congratulations on its acceptance! It is a much needed contribution.

    On the BAMS editorial process, your experience with the quick receipt of a Comment on your paper differs quite a bit with the BAMS handling of the Comment that I submiited on

    Hurrell, J., G. A. Meehl, D. Bader, T. L. Delworth, B. Kirtman, and B. Wielicki, 2009: A unified modeling approach to climate system prediction. Bull. Amer. Meteor. Soc., 90, 1819–1832.

    My comment languished for quite a few months, and ultimately appeared in 2010;

    Pielke Sr., R.A., 2010: Comment on ” A Unified Modeling Approach to Climate System Prediction”, Bull. Amer. Meteor. Soc., 91, 1699–1701, DOI:10.1175/2010BAMS2975. http://pielkeclimatesci.files.wordpress.com/2011/03/r-360.pdf

    They would not process my Comment (and not start the Reply process from Hurrell et al) until after their paper actually appeared.

    Hopefully, your experience demonstrates that BAMS is now more timely than in the past.

    Roger Sr.

    • Hi Roger, I was surprised to receive a comment so quickly, with the anticipation of a speedy publication. I asked the BAMS editors about this, and they confirmed this was their policy. This is a good policy (and I will definitely save their email describing their policy on this.)

      • I am curious if the editors gave (or could give) any examples of any such “rapid response” comment on any pro-CAGW paper?

    • I am surprised that your comments have been so long to emerge as well. The Hurrell et al paper is a small step in the right direction and your comments serve to remind us that unless sufficient account is made of the chaotic and non linear nature of our climate , any attempt to obtain worthwhile predictions from models are most unlikely to succeed.

  7. Congratulations Judy
    The poor evaluation of uncertainty in AR4 was one of my biggest objections any what I take it with such a big “grain of salt”. Hopefully IPCC authors will read and act on it. Often I see statistics analyzed as if the parameters were “random” when they are actually chaotic.

    May I encourage a paper on Chaotic Climate Uncertainty
    – to the degree it is possible to say what is known – and at least to emphasize what we know we don’t know – and highlight what we don’t know we don’t know. cf your posts:

    Chaos, ergodicity and attractors

    Spatio-temporal chaos

    • Hi David, your suggested topic is a good one, but unfortunately I am probably not the best person to write such a paper. I will think about it tho.

    • simon abingdon

      “The poor evaluation of uncertainty in AR4 was one of my biggest objections any what I take it with such a big “grain of salt”. This isn’t a typo, it’s just inexcusable carelessness. Why not read what you’ve written before you send it out to the world?

      • Mae culpa. Good advice.
        “and why I take it with such a big ‘grain of salt'”.

      • Because then people like you would have nothing to complain about.

      • simon abingdon

        Nothing wrong with accuracy and precision Steve; it’s the sine qua non of the scientific method.

      • I agree absolutely, Simon. I think you should have written:

        “Nothing wrong with accuracy and precision; THEY are the sine qua non of the scientific method.”

        Please read what you write before you post.

      • simon abingdon

        And I wasn’t complaining. I was just frustrated at not immediately understanding David’s intended meaning. Admittedly it wasn’t as confusing as your saying “causality” instead of “casualty” the other day on Climateaudit (and which you kindly acknowledged at the time).

      • simon abingdon

        Paul, how about “accuracy and precision is the name of the game”?

      • @simon,
        Yes, I agree. They is still appalling grammar.
        Personally,I believe that accuracy, precision, unbiased evaluation of alternative interpretations, a clear distinction between the different sources of uncertainty, the correct application of statistical theory to produce an objective assessment, having a sense of humour and getting a life IS the name of the game.

      • simon abingdon

        @Paul
        “having a sense of humour and getting a life”. What, you want both?

      • simon
        Thanks for your effort at “understanding David’s intended meaning.”
        I’ll take both joy and life!

      • Except, this isn’t science. And neither is this.

      • If you study the lives of the founders of modern science, you will discover that these are the very nursery of modern science.See Henry F. Schaefer, Science and Christianity: conflict or coherence? pp 14 – 31.

  8. Dr. Curry,

    This is an excellent paper, and really written to be quite understandable to the non-professional (albeit I will need to read it several times). My favorite take-away so far is this quote you used:

    “All models are wrong, but some are useful.” George E.P. Box

    • I agree, i really like the quotes. I shortened the paper from the original, eliminating some sections, and the most painful part was figuring out which quotes to eliminate.

    • As a business person and not a scientist, there is a parallel “saying” about budgets.

      “The only thing I know about a budget is that it is wrong. However, understanding how and why its wrong is the key value of the budgeting process.”

      This seems applicable to climate modeling. The only certainty is that the model will have variances from actuality. The value is in understanding the magnitude and cause of the variances.

  9. This is no minor issue. The quote on “very likely” must be the most often cited in the history of climate change. The new paper risks demolishing it and the AR4 with it.

    Imagine also the AR5 ending up with just a “likely” instead of “very likely”: the IPCC will be considered a bad, expensive joke by its political patrons, who’ll wonder why after all that time and money uncertainty would have increased.

    Therefore…EXPECT TOTAL WAR…

    • My expectation is that they will completely change the format of their statements, so that the AR5 statements will not be so directly comparable with the AR4 and previous statements. We’ll see.

    • It is astounding to me that a 95% confidence level, which would barely reach the “some possibility” level in rigourous science and statistics, is the gold standard for “likelihood” in the ARs.

      Excuses such as “gorsh, the climate is COMPLEX!” just don’t cut it.

  10. She who launched a thousand blogging duels, depicted in cartoons as Joan of Arc, thinly disguised as heroine of the West End play ‘The Heretic’, waved past the ‘sceptic-coach’ queue at the editorial peer gate check- in desk. Hard to trump that!

  11. Let’s cut the pleasantries …the comment was fast tracked lest some editor of BAMS risked resigning with a letter of apology to Benito Trenberth.

    Somebody should do a bit of text analysis and out XXX’s name. We know it wasn’t Kev, and it wasn’t Dessler. Has anybody heard from Jones of late?

  12. You will note that much of the criticism of Spencer’s papers is along the lines of
    “he only used 6 models….. he picked the models which gave the worst lag..’

    Now Judy, a model is a unique mathematical hypothesis. Each model should be able to be dripped into any time in Earths history and reproduce the know temperature change. Each should also be able to match real datasets, recorded by satellite.
    In real science, as opposed to climate science, the models would be made to jump through hoops. If a model is outside a 95% confidence interval, it fails and goes into the trash.
    We could very quickly eliminate the vast majority of the clutter in the field if you could set up a model Olympics; each contestant is given the know input of a year and we see how well they do. They are given the opportunity to model ENSO and a couple of other challenges; think robot-wars writ on climate models.

    • Matching Data does not prove a model is correct. Curve Fits can match data using parameters that are not even related to the problem. You must have valid representations of valid theory to have a “good” Model. if you have to put in little understood feedback parameters, not based on know science, you likely have more of a curve fit.

      • “You must have valid representations of valid theory to have a “good” Model. if you have to put in little understood feedback parameters, not based on know science, you likely have more of a curve fit”
        What the hell do you think they are other than glorified fits? They train them like performing seals to match the temperature records, adding aerosol fudge factors at will.

  13. Robert E. Phelan

    Congratulations on the publication of your paper. I’ll be downloading it and looking forward to the read.

  14. Dr. Curry,
    Congratulations on the paper. Your writing is clear and goes a long way towards the bottom line of this great issue.
    One question that comes to mind that I should have asked a long time ago relates to unintended consequences of policy choices.
    Do you see this as an area of concern that needs to be addressed?

  15. “My expectation is that they will completely change the format of their statements, so that the AR5 statements will not be so directly comparable with the AR4 and previous statements. We’ll see.”

    This has to be right because otherwise they’ll look like the moronic hacks that they are, even to their base. Bottom line, they can’t retreat, even a little given their statement of near certainty without sinking their own ship.

  16. John Carpenter

    I hope this paper gets a lot of attention. I thought it very interesting the way Dr. Curry describes the uncertainty monster becoming more enraged in step with the incremental level of certainty statements made by the IPCC from FAR to AR4. The FAR statement reads like a foreshadow of what’s to come in the following assessment reports and then each successive report ratchets up the level of certainty from ‘discernable’ to ‘most’ to ‘very likely’ to try and ‘exorcise’ uncertainty. All the while, the monster is really growing (though being ignored by the ‘consensus’) to the point where it simply cannot be ignored any longer. Well done!

  17. (The poor evaluation of uncertainty in AR4 was one of my biggest objections any what I take it with such a big “grain of salt”.) “This isn’t a typo, it’s just inexcusable carelessness. Why not read what you’ve written before you send it out to the world?”

    Yah, inexcusable all right. Hanging would be too good for the lazy bugger. (sarc, just in case it’s not abundantly clear)

    • The mind is a wonderful thing. I had to read it twice before I actually could see the error. It’s why we can finish each other sentences. It’s also the key to a quick wit.

      • simon abingdon

        My phrase “inexcusable carelessness” was way OTT. Apologies to David Hagen for overreacting. (I’m still surprised that mathematicians and physicists who have to be fastidiously correct in their expressions and equations often appear to be so lax where the written word is concerned).

      • simon abingdon

        “we can finish each other sentences”. Steve, I’m idly imagining you thinking “Hmm, other should have an s. Dammit, an apostrophe too. Where does that go? Sod it, best leave it as a typo”. I’m sure I mischaracterize you.

  18. Congrats on publication.

    I like the quotes.

    Otherwise – tldnr – sorry. I actually intend that in a constructive way. There’s a lot of info out there and only so many hours in the day. The quicker you can get your salient points across the better. 30 odd pages isn’t getting salient points across quickly; sorry. I’m not your intended audience by the way – so don’t go complaining.

    What I did read, – and I did try – seemed fine.

    Quite why where you thought the controversy might be I’m not sure. I’m reminded of Top Gear – who love to publicise any and every letter that a busy-body sends in and present it as evidence of how “edgy” the show is – so much so that it’s become an integral part of their brand – when in reality it’s just some middle aged men with a repetitious comedy show about cars.

  19. Harold H Doiron

    Dr. Curry,

    After reading your paper, I don’t get the message that a large, un-acceptable magnitude of AGW after the next 100 years will occur if we don’t take action to limit GHG emissions now, is “settled science”. If your paper generates a scientific controversy within the scientific community, then I question the political and social biases of the scientists who disagree with the observations and conclusions of your paper.

    The theory of increased concentrations of GHGs in the atmosphere as a mechanism for contributing to global warming seems to employ fairly straight-forward and well-understood radiation physics. We know that major regions of the globe are inhabitable, only because of the approximate 33 deg C global average warming contribution of our present level of GHGs. However, the magnitude of the warming due to anthropogenic sources of GHGs compared to natural sources and sinks of GHGs, as well as effects of other naturally occurring mechanisms affecting global and regional temperature variations, seems to be in great doubt. We know that the naturally occurring variations in the last 10-12,000 years provided a very stable climate system that has limited temperature variations within +/- 2 deg C of the average yearly temperatures of that recent geological period, and typically within +/- 1 deg C. When the climate warmed during this time period, it then always cooled again and warmed again in a very stable fashion with somewhat erratic small amplitude and frequency variations. The recent global temperature variations in the 20th century were well within these stable limits, even with the new effects of AGW mechanisms. We seem to be now holding at the recent maximum of this long established, erratic, but tightly bounded, cycling pattern of global average temperatures, and at a warmish temperature anomaly considerably below previous maximum anomalies in the 10,000 years before AGW forcing was established. There is considerable evidence that the natural climate variation mechanisms are stronger than the AGW contribution to date, and getting a better handle on them is the only way I see to have high confidence in what future AGW effects will have.

    Any useful climate model must model effects of the naturally occuring processes as well as the anthropogenic processes. In developing and validating complex engineering models, it is common practice to first validate subsystem models and to gain confidence in these individual sub-system models before tackling the more difficult problem of validating the integrated system model. To attack the uncertainty monster, one bite at a time, why don’t we:
    (1) Write down all of the naturally occurring mechanisms we know about (certainly we must, by now, know about the big ones such as solar radiation cycles, solar system orbital cycles, sea ice cycles, sea level cycles, earth albedo cycles related to sea ice coverage, humidity and precipitation cycles, effects of the earth’s magnetic field, cloud formation mechanisms, ocean heat mixing vs. depth, biological carbon cycles, atmospheric GHG exchanges with land and sea, etc.) and just assume that the unkown unkowns won’t have a big influence on our predictions of climate for the future.
    (2) Assign a sub-system model validation figure of merit and/or list reasons and evidence for believing that the sub-model has been validated to certain confidence limits or can be ignored without significant error
    (3) Identify priorities for improving these subsystem models and justify the funding for research programs to work on removing uncertainties where they currently limit the scientific and public policy decision making usefulness of climate models
    (4) Assess the uncertainty of AGW forcing vs. uncertainties in naturally occurring forcings and feedbacks to develop a rational assessment of the justified level of concern regarding anthropogenic hydrocarbon emissions. That is, how much time do we have before worst case scenarios with 50% (or X%) confidence levels emerge? Does that time horizon allow us time to improve model prediction capability before taking action that can cause other detrimental consequences that have to be considered in public policy decision making?

    If we take this time in 10 year increments, improving models, evaluating their prediction skill, and making new X% confidence predictions of time to go for worst case scenarios, couldn’t we manage our way forward without implementing “scientifically justified”, or perhaps “scientifically unjustified” hydrocarbon emission regulations that would put the USA into great economic disadvantage with respect to our world market competitors who don’t plan to implement similar hydrocarbon emission regulations?

    Personally, I would like to see a more organized climate science research effort along these sub-system model validation lines rather than continue the waste of funding studies where current un-validated models are exercised with different kludges and parameter variations to try to influence others in the scientific community as well as policy makers. As you mentioned in your paper, those of us in the engineering community where uncertainty in models results in unacceptable public safety issues, model uncertainty is eliminated to a much, much greater extent than current practices accepted within the climate science community. It is difficult for me to separate pubic safety issues from severe adverse national economic issues when using current climate change models as the basis for formulating public policy decisions regarding the need to restrict GHG emissions. Global average temperatures have not responded to continued anthropogenic hydrocarbon emissions in the last decade, so let us use this gift of time to improve our understanding of all climate mechanisms that must be modeled for accurate predictions.

  20. Congratulations, this is an excellent paper. I like the following quote :“All models are wrong, but some are useful.”

  21. 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.

    Shouldn’t the statisticians have a prominent seat at this table? To the extent that uncertainty can be quantified, they’re the ones who can shine some light on propagation of error, which is another way of saying propagation of uncertainty.

    OTOH, if we’re going to do AR4-style shoot-from-the-hip guesses, math is moot.

  22. Interesting that it seems to be assumed that the uncertainty would mean that the risks are overstated when in fact they could just as likely be understated surely.

    Might explain why the ice is melting in the Arctic ahead of AR4 expectations.

    I would not be at all suprised if the most accurate part of AR4 ends up being the melting of the Himalayan glaciers by 2035. A la “sods law”.

  23. Judith,

    Congratulations and bravo! Respect!

  24. Judith,

    You write “Such efforts should help tame the weather and seasonal climate uncertainty monster”

    Really? I would suggest you might not actually want that. When I do a Google search of the term “Uncertainty Monster”, there is no obvious reference that isn’t, in some way, connected to your use of it. So, it looks like he’s entirely of your, and possibly your husband, Peter Webster’s, own creation.

    It strikes me that this monster isn’t quite as big and scary as you make out. And you, for one, understand him, and are even fond of him!

    He’s actually a way to deflect attention away from what the science has actually concluded. There is always uncertainty in science, especially new science. The linking of this to some sort of “monster” is a tactic designed to promote the logical fallacy of suggesting that because we do not know everything, we therefore know nothing, and therefore no climate mitigation measures are currently necessary.

    Your science rejectionist supporters know this too and that’s why they call you a saint !

    • Very bitter temp, no surprise.

    • Temp, Tsk, tsk.

    • Your cartoon is false. Skeptical uncertainty is based on a lot of knowledge. For example, we have learned a lot about natural variability in the last two decades. If you cannot accurately state your opponent’s position then you do not understand the situation.

      • If you cannot accurately state your opponent’s position then you do not understand the situation.

        One often makes a remark and only later sees how true it is.
        ~ Ludwig Wittgenstein (using ‘subjective’ methodology and being oblivious to it)
        ———————————–

        Concerning Inverse probability/Bayesian Inference …

        Propositions show what they say: tautologies and contradictions show that they say nothing. ~ Ludwig Wittgenstein (using ‘subjective’ methodology and being oblivious to it)

        Subjective people are timely.
        They say what they presume.
        Their assumptions are felt and unspoken.
        ———————————–
        The “hole of silence” in a sea of noise

        Yet from those flames
        No light, but rather darkness visible

        ~ John Milton
        ————————————-
        Subjectivity is a timely volatile experience.
        Perceptions are in flux.

        The advantage of subjective thought is that it engages indescribable situations.

        Indescribable situations can be understood. –> !timeless

    • This is false and illogical.

      “monster theory” is not unique to Judith. Google it.

      The notion that there is some kind of slippery slope from fully acknowledging uncertainty to claiming that we know nothing is
      also bizarre. In all the climategate mails I read where scientists
      urged each other to fully acknowledge the uncertainties I can only
      think of a few individuals who argued that this would bring disaster. They of course tried to hide the monster and you witness the result. The attempt to hide the monster backfires. Nobody believes that uncertainty prevents action. You want to know an inconvenient truth? The effort to suppress expressions of uncertainty causes more uncertainty than would have existed otherwise. That’s what makes it monstrous.

      • The slippery slope for the CAGW activists is not “from fully acknowledging uncertainty to claiming that we know nothing.” It is from a level of certainty that justifies decarbonizing the global economy to anything less. That is why any deviation from the “consensus” must be marginalized and derided.

        I wonder when lukewarmers are going to grasp the fact that from the perspective of CAGW true believers, there is no substantive difference between a lukewarmer and a full fledged God fearing, smoking, diesel exhaust inhaling, science hating denier. Both deny the immediacy, certainty and scope of doom that is central to forcing the CAGW agenda on an unwilling populace.

      • Sorry, My experience with them has been different.

        no cookie 4 u.

      • Then you’ve evidently not tried to post a comment in the Guardian, have you ;-)

      • I think it would be interesting to have a couple examples of CAGW activists who have engaged in reasoned debate with a lukewarmer, or anyone else who dissents from the consensus for that matter.

        There was an extended exchange between Dr. Curry and Gavin Schmidt on Collide-a-Scape last year in which Dr. Schmidt was respectful, but the tone did not last long. And his dismissive rejection of Dr. Curry’s overall position regarding uncertainty was hardly what I would call respectful – ie.agreeing to disagree, rather than dismissing your opponent as naive and uninformed. That is the only thing close to a reasoned debate I have seen, and Dr. Schmidt was trying very hard not to come off as an activist, as he does regularly on Real Climate.

        But any examples of any of the hard core activists constructively debating their opponents (of whatever stripe) would be fascinating to see. Please link to a couple.

      • I’m possibly a lukewarmer myself. I would agree that it is entirely possible that climate sensitivity {2 x CO2} may well be as low a 1 deg C.

        However, its quite possible that it will be much higher.

        Isn’t that where the family pet, sorry uncertainty monster, is perhaps more of a hindrance than a help to you guys? We just can’t be sure and have to do our best to assign probabilities to each degree of warming.

        Judith may be right It could be as high as 6 deg C.

      • Sorry, Gary’s right. There are two kinds of people in the world, the ones on the bandwagon, and the ones not. All this hair-splitting over science and certainty becomes moot when you get to the policy stage. For the policy wonks, to paraphrase G. W. Bush, “you’re with us, or you’re with the young earthers”. All the science is just details.

      • Everyone needs to brush up on their rhetoric — I mean classic rhetoric — before engaging like this. Gary, your statements are guilty of the very thing you accuse. Your plea is for uncertainty to be allowed in debate. Then you make one hard conclusive statement of certainty after the next on the entire nature of the debate. What I gather from this is no one has a grip on certainty, but you do. Not very persuasive.

      • I’m not sure I follow this comment. I make no plea at all, let alone that “uncertainty..be allowed in the debate.” Uncertainty doesn’t need anyone’s permission to be part of the debate, it is the central issue in the climate policy debate without anyone else’s help.

        As far as “conclusive statement’s of certainty,” I make nothing of the kind on scientific matters. As to the nature of the debate, it is a certainty that decarbonization will do tremendous harm to the global economy. It is also a certainty that a socialist economy will, in time, implode. The system just doesn’t work in a modern world where central planning has to compete in the global.market with free market economies.

        I cannot say that I am certain that there are absolutely no CAGW activists who are engaging in open, respectful debate, but I have seen no evidence of any. (Fred Moolten for example is usually quite polite, but always dismissive, and impervious to even considering counterarguments of any kind.) Steven Mosher kept my cookie from me based on his own experience that he said was to the contrary. Unfortunately, he did not deign to share any examples of that contrary experience upon request. So I remain skeptical on that issue, but not certain.

        (By the way, rhetoric and logic are not the same thing. Nor is one a prerequisite for the other, as one can often see on this blog.)

      • It is also a certainty that a socialist economy will, in time, implode.

        So then, do you disagree with those who label European and/or Scandinavian economies as socialistic, or is it simply that they haven’t imploded yet but will yet still do so in time?

        And which economy is it that won’t implode in time? Do you have any historical examples?

      • Joshua,

        I do consider the European governments to be socialist to one degree or another. And they are exactly the reason I wrote that a socialist economy will implode “in time.”

        The Soviet Union was created on the corpse of decaying Czarist Russia and endured two world wars in its infancy. Yet it lasted for 74 years. China is building its socialist/fascist economy on a primarily agrarian society, much of which is still living on a few dollars a day.

        If you want to see the seeds of the implosion of Europe, all you have to look at is Greece, Spain, Italy et al. Euro-wide, political power is being ever more centralized in Brussels. The stupid voters are being read out of the process entirely. Meanwhile, Islamist enclaves are being allowed to emerge, and grow, with total control ceded to the local Imams.

        So yes, I believe Europe is socialist (so do most of the Europeans who label themselves as such, or some derivative thereof). And yes, unless the various countries start to pull back from the central planning abyss, which Sweden is showing strong signs of doing by the way, they will ultimately implode.

        You don’t need to go to Europe to see economies on the brink of implosion under the weight of modern socialism. Just look at California and Illinois.

        Which economy won’t implode in time? Well, since free markets are a relatively new phenomenon in this world, and still very much in the minority, it is still questionable whether such an economy can escape the constant lust for power of progressives. Conservatives build things and employ people. Progressives seek power and control of government. Unless conservatives can learn how to tame the progressive beast, it is not at all certain that a culture and an economy likes ours can “long endure.”

      • Okay, here are some specifics about why your position in the post you wrote is based on multiple fallacies:

        [1] You accuse CAGW activists of a failure to accommodate uncertainty. I understand this — the evidence points to it, but is not open-and-shut. That’s fine. But then you exaggerate. As quickly as you deride the certainty of people you perceive to promote CAGW, you make an even more impossible claim: “any deviation from the “consensus” must be marginalized and derided.” Really? “Must?” Not only are you presenting assumptions as factual conclusions, it’s also a perfect example of the “stolen concept” in rhetoric. You say CAGW activists, steeped in their certainty, marginalize and deride. And so you, in your certainty of their existence and behavior, deride them.

        [2] You make an ad hominem attack. It’s not a horrible ad hominem attack, but ad hominem attack nonetheless. I could fill this blog with at least 10,000 names of people who are anything but “CAGW activists.” And I wouldn’t have to look hard to find them — they simply believe the evidence points toward global warming and would like to see our society shift toward renewable and clean sources of energy. Using the term, of course, provokes. “Activist” connotes someone who is difficult to deal with and usually incapable of weighing various points of view.

        [3] “CAGW activists” is a straw man. Try as much as I did–digging up at least 30 prominent researchers–I could not find a single example of a marginalizing deriding “CAGW activist.” The closest I could think of is James Hansen (NASA/Columbia U). But I couldn’t find a record of him deriding or marginalizing anyone, except maybe the coal industry. Unless you mean your brother-in-law or some guy from work, there is no pattern of the existence of “CAGW activists” who marginalize and deride. It’s an illusion.

        [4] “from the perspective of CAGW true believers, there is no substantive difference between a lukewarmer and a full fledged God fearing, smoking, diesel exhaust inhaling, science hating denier.”
        Another assumption presented as a factual conclusion. I am a true believer in catastrophic anthropogenic global warming and I see a big difference between a lukewarmer and, say, Sarah Palin. You know where the blogs and research papers are — try to find one statement by a scientist who says there’s no difference between a lukewarmer and a science-hater.

    • tt,
      You had a chance to make yourself look well informed and insightful.
      You chose to create the opposite impression.

    • Hmm. Why is it assumed the monster is a he?

  25. “The linking of this to some sort of “monster” is a tactic designed to promote the logical fallacy of suggesting that because we do not know everything, we therefore know nothing, and therefore no climate mitigation measures are currently necessary.”

    Funny how everyone considers himself a logician these days.

    • pokerguy, “Monster” Know more?
      I think it is safe to say that what the science of AGW has cost us all to this point, is to much. Especially when we consider what we now know, after just a couple of years of serious review of the IPCC and the job done. Knowing what we all know today, are you also a logician?

      • Tom, I have no idea what you’re asking me. If you want to try again in plain English I’ll be happy to try and give you an answer.

      • pokerguy, This being said,

        “The Intergovernmental Panel on Climate Change (IPCC) is the leading international body for the assessment of climate change. It was established by the United Nations Environment Programme (UNEP) and the World Meteorological Organization (WMO) to provide the world with a clear scientific view on the current state of knowledge in climate change and its potential environmental and socio-economic impacts. The UN General Assembly endorsed the action by WMO and UNEP in jointly establishing the IPCC.”

        Perhaps you would understand this too? Scientist of the hole world, try their BEST, to prove their PET A theory that: ‘We are thick-as-a-brick.’ So far it looks like a partial success, to date. Have a good one. And, thank-you-for-asking.

  26. Dr. Curry,

    First of all, congratulations to you and Dr. Webster :-)

    As for the uncertainty monster surrounding the climate change issue, I can only hope this paper and the forthcoming issue in Climatic Change on framing and communicating uncertainty for the IPCC will help, and pave the way for the IPCC to do a better job of characterizing and assessing uncertainty. [emphasis added -hro]

    Considering that the IPCC appears to have (for all intents and purposes) dropped the lifeline handed to them by the IAC’s recommendations for improvement in their processes and procedures, I hope that your hopes are not misplaced!

    Certainly, the IPCC’s own spin machine on the 2007 publication AR4 did very little absolutely nothing to highlight any element of “uncertainty” vis a vis attribution, as demonstrated by the following press releases from the UN and the UNEP (and also reiterated by the WMO but with the rather curious preface: “For use of the information media. Not an official record”)

    Evidence is now ‘unequivocal’ that humans are causing global warming – UN report

    Evidence of Human-caused Global Warming “Unequivocal”, says IPCC [From UNEP site]

    Reading through these two press releases, I was left with the impression that – while mentioned – “uncertainty” was far from being a concern. Also, somewhat conspicuous by its absence was any mention of “natural variability”. Although I should, in fairness, note that both press releases contain the following:

    [The IPCC’s] reports have played a major role in inspiring governments to adopt and implement the United Nations Framework Convention on Climate Change and the Kyoto Protocol

    I am not a climate scientist (nor any kind of scientist for that matter!), but it seems to me that there is a distinct disconnect between whatever “uncertainty” might have been evident in the opus known as AR4 and “unequivocal” claims in headlines such as the above, reinforced by the UNEP’s Achim Steiner who wrote (in an undated editorial accompanying the above):

    There can no longer be any serious doubt that humanity’s emissions of carbon dioxide, methane, nitrous oxide and other greenhouse gases pose a very real risk to our well-being, and that children born in 2007 will live in a warmer world of greatly altered weather patterns and higher sea levels.

    How should we respond to these findings? Scientists themselves will interpret the policy implications of their findings in different ways. My view is based on my own values: that we must act as responsible stewards of this planet, respect the rights of others, including future generations, and take precautions against potentially large risks even in the face of uncertainty or the absence of absolute certainty.

    The scientists have done their job. It is now up to governments, and indeed everyone of us, to transform their comprehensive and incontrovertible findings into public policy. [emphasis added -hro]

    Steiner’s assertion that “scientists have done their job” is quite astounding! Does this not suggest that there’s no work left for them to do (except “interpret the policy implications of their findings” – a task that makes one wonder which part of the science curriculum qualifies them to make such interpretations)?! And does this not also call into serious question the very need for AR5?!

    • Hilary, thanks very much for these links. I will use some of these quotes in my upcoming seminar on this topic at MIT.

      • You’re welcome! I should have noted that credit for unearthing the UN and UNEP versions should go to PaulM [via comments at BH]

        But I found the other two ;-)

        Not sure about your audience at MIT, but readers here might also be interested in knowing that these press releases appear to contain the seeds of the “talking points” we have seen repeated ad nauseam since 2007. Not to mention that Googling: “‘played a major role in inspiring governments to adopt and implement’ +unequivocal” gave me 101 results, while “Human-Caused Global Warming Unequivocal” yields 3,300.

        One might, therefore, reasonably conclude that the effectiveness of the IPCC’s PR machine is “unequivocal” – if not “incontrovertible”. In fact, Pachauri was crowing about it in July 2009:

        [T]he IPCC AR5 is being taken in hand at a time when awareness on climate change issues has reached a level unanticipated in the past. Much of this change can be attributed to the findings of the AR4 which have been disseminated actively through a conscious effort by the IPCC, its partners and most importantly the media […]

      • The IPCC works under the auspices of the UNEP. For UNEP to substantially misrepresent the IPCC’s findings, with the apparent acceptance of the IPCC, is very telling.

      • there are two parts to the UNEP research programmes.the constraints under the MP allow governments that were unhappy(read science academy) with a number of conclusions in AR4 in stratospheric assumptions. This was the reason for the inclusion of the additional chapter in the expert ozone assessment 2011.

        The current chapter helps to place the Protocol’s climate impact within a wider context by critically assessing the effect of stratospheric climate changes on the troposphere and surface climate, following a formal request for this information by the Parties to the Montreal Protocol. As requested, the current chapter also considers the effects on stratospheric climate of some emissions that are not addressed by the Montreal Protocol, but are included in the 1997 Kyoto protocol. Hence, the chapter covers some of the issues assessed in past Intergovernmental Panel on Climate Change (IPCC) reports (IPCC, 2007; IPCC/TEAP, 2005). The current chapter is designed to provide useful input to future IPCC assessments.

      • Dr. Curry to make one correction the IPCC was formed under the co-auspices of the UNEP and the WMO:

        The Intergovernmental Panel on Climate Change (IPCC) is the leading international body for the assessment of climate change. It was established by the United Nations Environment Programme (UNEP) and the World Meteorological Organization (WMO) to provide the world with a clear scientific view on the current state of knowledge in climate change and its potential environmental and socio-economic impacts. The UN General Assembly endorsed the action by WMO and UNEP in jointly establishing the IPCC.

        Also it doesn’t actually work under the UNEP, if it “worked” for any part of the UN technically it would be the WMO since it is HQ’ed in the WMO building:

        It is supported by WMO and UNEP and hosted at WMO headquarters in Geneva.

        http://www.ipcc.ch/organization/organization.shtml

        Also the reason for the misrepresentation is because unlike the WMO the UNEP is a political organization.

        So why is it telling, now, in 2011 that the UNEP would misrepresent the IPCC findings for political purposes when it was stated in a meeting they had convened back in 2007 they were going to do so?

        You can verify it yourself the document is online:

        The UNEP That We Want

        Reflections on UNEP’s future challenges
        Prangins, Switzerland, September 17, 2007
        Mark Halle

        At the request of UNEP and with funding from the Danish Ministry of Foreign Affairs and UNEP, IISD convened a group of individuals with substantial experience in international environmental affairs to reflect for a day on the nature and evolution of our environmental challenges, to discuss appropriate responses and to consider the role of UNEP in deploying these responses. They met in Prangins, Switzerland, on September 17, 2007. This note summarizes some of the reflections recorded during the day.

        [SNIP for brevity]

        Vision
        Addressing the current environmental challenges requires the environment to move to the centre of political and economic decision-making. It follows that UNEP must evolve from being a marginal player at the intergovernmental level to becoming a central player. The argument for doing so rests on the recognition that the prosperity of the world—both achieving greater prosperity in most of the world and maintaining the prosperity that exists already in some parts—depends on maintaining the productivity of the world’s major geo-biological cycles. As these are all under serious threat, we must accept that our prospects for prosperity are similarly under serious threat.

        Responding to this threat requires sound science, good policy and astute politics. UNEP has proved competent in mobilizing the first; occasionally competent in the second; and largely absent in the
        third. It must urgently seek to correct this imbalance.

        [SNIP for brevity]

        It is clear that UNEP must take advantage of windows of opportunity to make its case. Like a surfer, it must spot the waves it can ride. The biggest, most magnificent political wave at present and in the immediate future is climate change, and UNEP should not fail to ride it. But it must find and occupy its niche.

        http://www.foxnews.com/projects/pdf/113009_IISDreport.pdf

        So why so it be surprising that a political organization that stated they want to become more central to the politics of Climate Change would try to do that by misrepresenting the AR4 findings for political gain? Especially 4 years after they said they were going to do that.

      • It is important to remember that we are in the era of “Unequivocal equivocation”
        See: On The Current State Of Climate Science: Unequivocal Equivocation – An Open Letter To Dr. Trenberth

        Somewhere Physicist William Happer reminded us that almost nothing in Physics is “unequivocal” – how much less in climate science that is so little known.

    • What’s with all the complaining and schadenfreude from many of the commenters on this blog? For instance, instead of being up in arms about what Achim Steiner said why not just contact the man and get it clarified? You can reach him through an admin. asst. at: Corli Pretorius, Executive Assistant to the Executive Director Corli.Pretorius@unep.org.
      I was hoping this blog would be about science and give me good food for thought. Part of it is. But there are two basic human energies that one can choose: be for what one is for, or be against what someone else is for.

  27. “Specifically with regards to solar forcing, a rigorous uncertainty assessment would have included a systematic exploration of individual model sensitivity to different solar forcing datasets and the associated range of uncertainty. Further, some account for known unknowns associated with indirect solar effects should be included in any assessment of confidence or likelihood. ”

    Bravo Judith!

  28. Norm Kalmanovitch

    Science starts from a foundation of what is known and projects into the unknown using theory backed up by observation and experimentation to tame the uncertainties of the unknowm and bring them into tem realm of the known.
    Starting from what is known about global temperature we know that the Earth has been cooling since 2002.
    Starting from what is known about CO2 emissions from fossil fuels we know that these emissions increased from 26.301billion metric tonnes in 2002 to 33.158billion metric tonnes by 2010. The key question about the uncertainty of future climate is when this nine year trend of global cooling with the concurrent rapid increase in CO2 emissions from fossil fuels will revert to the catastropic global warming perdicted from these same emissions by the overwhelming scientific consensus claimes by the IPCC?

    • Thanks Norm for you pertinent question.

    • I have a draft post on this topic, early hint: maximum of 17 years, according to a new paper by Santer et al.

    • I have trouble reconciling the embrace of uncertainty in some areas of climate science (attribution, severity of projected outcomes), with acceptance of such precision in other areas (the temperature record, CO2 emissions data etc.).

      Given all the variables in ocean heat content, the debate about citing of surface stations, the acknowledged “missing heat,” I still have trouble accepting that a global average temperature can be determined on an annual basis to within tenths of a degree, or that emissions of C02 and the consumption of fossil fuels can be quantified with such accuracy..

      I have as much difficulty with claims that there has been measurable global cooling since 2002 (or 1998), as I do in accepting that we can discern a .1 or .2 degree increase in global average temperature per decade currently. (And forget about such precision based on proxies.

      Personal experience, anecdotal evidence and observations certainly seem to support both conclusions, particularly with respect to land surface temperatures. But a true global average, including the entirety of the oceans, land and atmosphere? What happened to uncertainty?

      “emissions increased from 26.301billion metric tonnes in 2002 to 33.158billion metric tonnes by 2010”

      Information on the burning of fossil fuels is based on data provided by governments and industry. Does anyone really believe that even the Chinese and Indians themselves know how much fossil fuel is being burned in their economies on an annual basis?

      The U.S. can’t even get its own unemployment or inflation numbers correct.

      It just seems to me that people are all enthused about accepting levels of uncertainty that support their own position, but less interested in the topic when it might conflict with their existing views.

    • I would not use cooling, but neutral, since that is what it is. Questions would be should this period be cooling, but not because of more CO2, If not, then climate shifts have warming, neutral and cooling modes with possibly a more cooling mode with a higher average temperature and a more warming mode with a lower average temperature.

    • You can see periodic cooling regimes in an otherwise upward trend.
      There are a large number of reasons for this. Why? because the climate is determined by more than one variable. Gavin put the figure at around 13? years, I’ve seen 15 years.. Judith suggests 17 years.

      It depends on many factors including the fundamental noise in global measures.. That alone can give you 10 year stretches with no warming..

      • steven mosher

        These “periodic cooling regimes in an otherwise upward trend” have been limited to periods of 9 years or less (1979-1987) since the mid-century cooling cycle ended around 1976 and the beginning of the “widely acknowledged ‘climate shift'” [IPCC AR4, Ch.3, p.240].

        The latest “lack of warming” has lasted statistically since early 1998, so a bit more than 13 years.

        But it will apparently only become “statistically significant” if it lasts 17 years, so we still have a few years to wait.

        Just a question: do you think if it really lasts 17 years, the “goalpost” for “statistical significance” will be shifted?

        Max

    • Loehle & Scafetta (2011) and others are modeling a ~60 year PDO type cycle with ~30 years of cooling to about the 2030s. See “Easterbrook”, PDO or AMO
      However, Ed Fix has a fascinating model of solar cycles based on the barycenter, that is predicting several short cycles.

      So guess we may need to multiply Santer et al.’s 17 years x 1.2 to 2. to about 20 to 30 years to account for PDO – unless someone can predict the next Krakatoa and consequent Volcanic Winter.

      Let the Climate Games continue.

  29. Judith,

    I’ve already accused you, and your husband, of trying to pass off your family pet as a monster. You don’t seem to like hard core denialists bringing sky-dragons into the argument, so why copy their lead?

    If you want to say, as you have, that IPCC confidence limits need to be widened, and there is a 16.6% chance of 2x CO2 climate sensitivity being higher than 6 deg C, then of course that’s fine; but, why do you feel a need to use allegorical associations?

    • I suppose you could ask the same question of ‘the world has a fever’, the ice is in a death spiral, we have a ‘greenhouse’ effect, C02 is a control knob. Merchants of doubt….If you haven’t noticed our thought is metaphorically structured. I’ll recommend a book “metaphor’s we live by” You might recognize one of the authors.

      Metaphors work best when they allow you to structure or understand the “less well known” with categories from the “more well known.” As for your suggestion.. there is no logical requirement for Judith to move from a description of how we handle uncertainty (using a metaphor) to an actual number.

    • I think the skydragon is a wonderful metaphor, it just that their physics is incorrect.

      How does my statement about widening the IPCC confidence limits imply a 16.6% chance of climate sensitivity greater than 6C? you seem to have missed my main point. The uncertainty is too great for a pdf and statistical uncertainty. We know unambiguously the sign of the sensitivity. We can put some broad bounds on it, but the point of my argument is that trying to come up with a mean and standard deviation, given the uncertainties, is misleading. I’ve written entire posts on this topic.

      • Nor do we know the sign of the sensitivity if we are talking about the actual possible future climate, as opposed to a theoretical construct. My monster taxonomy would include monster confusions such as this one, as well as uncertainties. The fact that CO2 is a GHG does not mean it has to warm when CO2 levels rise. Saying the sign is unambiguous seems to imply that it does have to warm. This is the fundamental confusion in the debate, abstraction versus reality.

      • How can we be positive of the sign of the sensitivity for a system with a region of instability? In general, sensitivity is positive, but with the potential of a glacial operating point, the upper boundary is somewhat limited. If we were operating from the glacial set point, the sensitivity would be definitely be positive and the upper boundary more uncertain.

      • I am not completely sure if we can claim to know unambigously the sign of sensitivity.

        http://pielkeclimatesci.wordpress.com/2011/02/08/new-paper-climate-stability-and-sensitivity-in-some-simple-conceptual-models-by-j-bates/

        Quote from the paper: “Some unexpected outcomes are found in this case. These include the possibility of a negative global average temperature response to a positive global average forcing, and vice versa.”

        That sounds very much like the possibility of a negative sensitivity, no matter how strange and counterintuitive that may appear …

      • Judith,

        You ask: “How does my statement about widening the IPCC confidence limits imply a 16.6% chance of climate sensitivity greater than 6C?”
        Earlier this year:
        http://judithcurry.com/2011/02/26/agreeing/
        You wrote:
        I think we can bound this between 1 and 6C at a likely [66%] level, I don’t think we can justify narrowing this further.

        So, approx 17% chance of it being more and 17% of it being less than this range. Is that a fair comment?

        So if, as you also say, risk is the product of consequences and likelihood: what can happen and the odds of it happening, how on Earth can you possibly be saying, or give the strong impression that you are saying, there is no case for climate mitigation?

        How is it possible to believe this and yet have so many climate science rejectionist supporters on Climate Etc ?

      • my whole point is that there is no “normal distribution” so your division of some remaining uncertainty into two equal sides of 16.6% is exactly what I am arguing against doing

      • I don’t think the distribution has to be “normal”, or even symmetrical, does it? If confidence intervals are specified, the result is just as likely to be above the specified range, as below it, regardless of the shape of the distribution.

        I must admit that I’m not 100% sure that I’m right in saying that. Maybe others, with more statistical knowledge, would like to comment.

        In any case, I’d say my point is still valid. Risk is still the product of consequences and likelihood. The consquences of a 6 deg C climate sensitivity, which is your figure not mine, are enormous.

  30. The real IPCC “monster” is unacknowledged and poorly assessed uncertainty, selectively ignored to permit false expressions of certainty.

  31. Congratulations on the paper.

    I particularly liked the last paragraph on page 13, which seemed to shine a light on productive future directions.

    I believe some monster heuristics were missing from your lexicon.

    eg:

    a) Monster wrangling: the analysis is conducted with acknowledgement of uncertainty and oriented to sidestep the areas of greatest uncertainty, use uncertainty against itself, or otherwise leverage a solution space by minimizing the impact of uncertainty on the problem-solving process.
    b) Monster corralling: categorizing like areas of uncertainty together so reasoning becomes comparable and familiar, as in reasoning by analogy, where for example two or more problems with similar ontic aspects are discussed in parallel; the most familiar of the problems becomes a metaphor that bridges understanding and suggests similar approaches concerning all such monsters.
    c) Monster branding: name the monster not by its confidence or certainty, but by its challenges and spans, by what the monster forbids to be done with the conclusions. If models are non-predictive, they ought explicitly be called Non-Predictive Models. If curves are ontically unpredictable, they ought be described as Unpredictable Climate Functions.

    Overall, would have wished for a tighter approach that enlisted more examination of potential solutions, or at least was more evenhandedly critical of the present state of reactions.

    However, the subject is important, and too little discussed, and from here, who is to say where the discussion may go?

  32. “but, why do you feel a need to use allegorical associations?”

    I’m guessing because images are effective means of communicating complex or at least in this case, nebulous ideas. “Uncertainty” is an abstract concept, and not particularly compelling in terms of getting attention.

    Plus, I think “monster” is an apt metaphor. IN psychic terms, monsters are often understood to be representations or expressions of our own deep-seated fears. When we expend energy in attempting to repress these fears ( in this case of “uncertainty”) even further, our monsters only grow bigger. We can’t ever tame our inner monsters, but we can find a way to live with them more comfortably by admitting they exist. In other words by doing what Dr. C is doing, that is bringing them into the open.

    I think it’s a good choice.

  33. boballab | September 11, 2011 at 12:07 am

    So why is it telling, now, in 2011 that the UNEP would misrepresent the IPCC findings for political purposes when it was stated in a meeting they had convened back in 2007 they were going to do so?

    Just for the record, those press releases are from Feb. 2007 (i.e. prior to that meeting!) Considering that the UNEP, not too long ago, silently took down its map of “climate refugees”, IMHO, it is even more telling that this misrepresentation of the IPCC’s findings remains in its pristine state.

  34. Nice paper, but to echo P.E.’s comment, to address issues of uncertainty it would be useful to engage a statistician as a collaborator. I’m not a climate expert, but it appears that almost all of what is (claimed to be) known about the relationships of explanatory variables to measured aspects of climate have come from data. Statistics is the science of data analysis formally grounded in uncertainty (probability). Statisticians routinely work with subject matter experts in a variety of fields to develop models that are scientifically sound with uncertainty assessments that are scientifically sound as well. For example, biostatistics is an entire subdiscipline devoted exclusively to collaboration between statistics and human health. Epidemiologists and research MDs routinely seek this collaboration. Why have climate scientists, who work with reams of data on a routine basis, not done the same?

  35. For me, there is NO uncertainty in the global mean temperature pattern:

    http://bit.ly/ocY95R

    “Accelerated warming” of the IPCC is incorrect.

    Expect global cooling by about 0.3 deg C in the next two decades.

  36. As already written by Judith, the truly telling bit isn’t the UNEP spinning things its way, but the IPCC keeping quiet about it, thereby confirming science has always been the lesser partner to politics.

  37. “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.”

    One of the problems of discussion is the importance attributed to this statement. Ultimately it doesn’t matter, what has happened over the last 50 or100 years, what we are really interested in is, what’s going to happen over the next 50 or 100 years.

    The whole issue of global warming was introduced without much understanding of the past temperature changes, and this was fully admitted by the climate scientists of 1970’s and 1980’s. The only strong empirical evidence concerned the rise of the CO2 concentration measured at Mauna Loa and later also elsewhere. Based on theoretical understanding of the Earth system this increase was estimated to lead to a significant warming, and it was concluded that this warming might reach seriously damaging levels.

    Thus the original way of setting the question was:

    What can we say about the expected warming based on theoretical and general understanding of the Earth system and the limited empirical data that’s available?

    Very many, if not most, climate scientists consider this the relevant question and the question of the relative share of anthropogenic influence over the last 50 or 100 years to have only lesser and indirect significance as one of the many factors that contribute to our present level of knowledge. Much of the disagreement of public discussion is related to the relative weight given on the attribution of the 20th century warming.

    The attribution of the warming of the last 50 years has obtained a bloated status similarly with the hockey stick. Both are considered as essential in the public debate, while they are not really as important from the point of view of science. In the science the set of evidence is diverse and the role of any specific factor is limited.

    The problem is that it’s not possible to describe in clear terms what’s the totality of evidence, or how much weight any particular data has for the overall understanding. It’s not possible the evidence well to the general public, but as far as I can see, it’s not possible among the scientists themselves either. The evidence remains fragmentary. Actively working climate scientists know more about it than outsiders. They have certain trust that their views are justified, but they cannot describe systematically, why it’s so or how strong their subjective evaluations are.

    Personally I do believe that the working scientists as a group do indeed know quite a lot more than others on the climate change, but I don’t think they can estimate themselves, how much they do really know. When they cannot do that themselves, we outsiders have even lesser possibilities in judging the actual level of understanding. It’s not as poor as skeptics think, but it’s not either as solid as politically activist scientists tend to claim, when they try to get the public to support their conclusions.

    • Pekka, what is the source of your ‘original question’ quote? Is it early IPCC? In any case note that warming is “expected,” which we now know to be incorrect. Indeed natural variability was not generally recognized until the late 1990’s. I mark the NAS Dec-Cen Variability report as the turning point.

      The proper question should now be something like “to what extent is climate predictable and what, if anything, can be expected?”

      However, attribution must be central because the policy issue is paying the bills. The multi-billion dollar USGCRP has always been justified on the basis that it will resolve the climate policy issue. As an abstract scientific issue climate is not that important. It would be lucky to get a tenth of its present budget.

      • There wasn’t any IPCC in the 1970’s. The logic is the opposite. IPCC didn’t create that expectation, that expectation led to the creation of IPCC..

        I learned about the issue of CO2 and global warning from a study of the Intenational Institute for Applied Systems Analysis, IIASA: “Energy in a Finite World”. That study was done in the aftermath of the oil crisis of 1973-4 and was published in 1980. That study presented the following conclusions concerning the influence of CO2:

        As for the carbon dioxide problem, because of the large uncertainties in the present knowledge of the carbon cycle it is not possible to quantify with a high degree of certainty the possible buildup of carbon dioxide in the atmosphere due to continued large-scale reliance on fossil fuels over the next 50 years. If the generally held “views” on the magnitudes of sources and sinks and transfer rates of carbon dioxide are accepted, it appears that the atmospheric concentration of carbon dioxide may increase by 20 to 100% over the next 50 years, depending on the global level of energy consumption and the extent of reliance on fossil fuels.

        The corresponding increase in global average surface temperature would be in the range 0.5 to 2.0 K. However, one should not expect the same temperature changes in all parts of the globe – some areas would experience greater and some smaller changes. Additionally, there would be regional changes in other climatic variables – of particular significance is rainfall.

        Nevertheless, in view of the present uncertainties in quantifying the effects of carbon dioxide it seems premature to recommend only such energy strategies that actively discourage the use of fossil fuels. At the same time, in view of the probable climatic implications of increased concentration of carbon dioxide in the atmosphere, it would be unwise to build future energy strategies that continue to rely greatly on the use of fossil fuels. A prudent policy, in our opinion, would be to have sufficient nonfossil options incorporated in the energy supply system over the next few decades so as to allow expansion from that base, if necessary, as the effects of carbon dioxide become better quantifiable through further research.

        As I wrote, this is from 1980, and this not from a climate study, but from an extensive energy study lead by Wolf Häfele, who had worked earlier in nuclear energy research.

        As far as I know, nobody had thought about IPCC or anything similar in 1980.

      • Fine, but you said 70s and 80s and the IPCC was formed in 88 so it was a reasonable question. In any case my point stands that even in 1980 they assumed incorrectly that they knew what the actual CO2-temperature link was. (Increase CO2 by 20-100% = increase global temperature by 0.5-2 degrees K.) We now know that this conviction is wrong and we need to reformulate the research program accordingly. The 40 year old paradigm has failed and the new paradigm is in view.

        I never suggested that the IPCC created the expectation. The IPCC was created largely to promote and defend the expectation. I believe IIASA is still active in this regard as well.

      • The most visible role of IIASA in IPCC related activities was in preparing the SRES scenarios for the TAR, but there’s also much own climate related research at IIASA. There have been many changes in the personnel and other influencing factors since I last visited IIASA, and I’m not quite up-to-date with their present activities.

        IIASA was created as an East-West meeting place of systems scientists during the cold war years with large part of funding from USA and Soviet Union. When that reason has disappeared, IIASA has lost part of its funding, but it has so far succeeded in finding some new approaches to maintain sufficient funding to continue its operation. Project based funding is now more important, and Germany has become the largest source of funds in that.

        Service type research for IPCC needs has formed some part of the project work, but I think it’s share has been declining as IIASA has searched for scientifically more ambitious activities.

      • Alexander Harvey

        “The climatic fluctuations of the last few decades are minor compared to those contained in the historical and geologic records.”

        “The long term impact of atmospheric carbon dioxide on climate”
        G. MacDonald et al 1979 (JSR-78-07)

      • David,

        To make justified policy decisions the costs and benefits of that decision must be compared in some way. In that all risks and uncertainties have an important role. The costs and benefits depend on the future, the attribution of the past warming has no direct influence on that.

        Attribution of the past warming may be a significant factor in judging, what we can say about the future, but it need not be, as it’s only one argument of many. It may be the most easily understandable to non-scientists, but that should not determine it’s weight. The weight of every source of understanding should be judged looking, how they really influence the best available estimates and their uncertainties.

      • Pekka, any decision to decarbonize the global economy to prevent dangerous global warming absolutely requires a firm determination that humans are causing the observed warming. Otherwise it is all just theory. Attribution is a logically necessary condition for adopting a forceful decarbonization policy.

      • A firm determination probably converges on some multi-variable, multi-factor, time varying estimation of past present and future behavior.

        Forcing a reduction of the overview to a single variable scalar for the sake of making a yes/no (?) decision can help and/or hinder.

        Alternately, decisions may be needed and it’s not easy to avoid falling into the conundrum caused by premature convergence.

        There is a very real problem of wishing to decide things to certain extents, extending short intervals into the future. What if it is undecidable? Does one remain paralyzed or concurrently follow alternate plans B,C and R?

        The panic of deciding and doing everything now with today’s knowledge has been detrimental and beneficial. Excessive forcing the response, boosts the detriment relative to the benefit.

      • David,

        What’s logically needed for a wise decision is that its outcome is better than alternatives taking all risks and uncertainties into account.

        What’s logically needed for a political decision is ability to sell it.

        Both of these are helped with attribution that provides convincing evidence of human contribution to the past warming, but there are no logically binding reasons to require that for either wise or real decision making. Wise decisions can logically be based wholly on evidence of different type, and real decisions can be based on anything including gross errors and cheating.

        You may personally require some specific type of evidence, but that’s neither obviously wise nor likely be in agreement with the requirements of others. You may find some justification for your views from the history of U.S., but you may most certainly find also contradicting evidence both from U.S. and from other countries of many different political system.

      • What do you mean by “firm determination”?

        A more intelligent way of looking at the problem is to try to estimate the risks involved. I’ve mentioned it before before, but the definition of risk as the product of consequence and likelihood seems a good one IMO.

        So what’s the likelihood, and what are the consequences, of a greater than N deg level of warming? Where N = 1 deg, 2 deg, 3 deg etc

      • David Wojick

        “..any decision to decarbonize the global economy to prevent dangerous global warming absolutely requires a firm determination that humans are causing the observed warming. Otherwise it is all just theory. Attribution is a logically necessary condition for adopting a forceful decarbonization policy.”

        This is an enormously broad and largely specious contrary condition.

        _Any_ decision?

        Really?

        All possible decision, the entire universe of choices, is predicated absolutely on a firm determination?!

        I’ve never met or heard of a policy analyst in government who absolutely predicates all decision on any one thing. Have you?

        That’s more like the realm of fringe presidential candidates.

        And what scientific finding do you expect to be absolute?

        And by firm, what can you possibly mean?

        Is there a specific measure of firm determination you refer to, David, in science or in policy?

        Is it 100% confidence and 100% certainty?

        Of course it cannot be, there are no such things where sane science or policy is involved; yet you make no provision for disambiguation and every rhetorical device to indicate strong implication of the highest level imaginable, so semantically while you seem to be trying to make a reasonable assertion, the logical equivalent to your statement is, “No matter what science tells us, ‘we’ must entrench the emission of carbon as if it were an enshrined and undiminishable right, equal to our most cherished and holy prizes.”

        Freedom of speech does not enjoy the status you confer by your precept upon carbon emission.

        Not a single right in the US Constitution is held to such a bizarrely irrational standard.

        Attribution, in the real world as it is presently constituted, is only logically necessary at a balance of probabilities for a civil court to find liability.

        Liability is a forceful measure.

        Your claims fail on the most rudimentary of logic, and on the most naive examination of reality.

        Respectfully, one would expect better.

        Attribution is most interesting post factum, in cases of liability.

        It is thus the preserve of the costliest response to the costliest outcomes, not the range of rational policy.

        All decisions based or reason ought consider risk abatement and risk impact, individual rights and consent, democratic determinations by valid methods of choosing options, and at the same time such decisions should be absolutely and firmly fortified against bias, prejudice, irrationality, and ignorance such as your precept amounts to.

      • @ Bart R

        Nicely teased apart… as if it were a pulled pork sandwich

        the meat becomes tender enough that its weakened connective tissue allows the meat to be “pulled”, or easily broken into individual pieces. Pulled pork is found around the world in a variety of forms.

        Appropriately pulling apart into individual perceptual chunks isn’t easy. It’s a challenge for ‘description’.

        Well done.
        Nicely cooked
        :-D

  38. The IAC said statements in IPCC reports such as ‘very likely’,etc were unsupported scientifically..

    Yet, the UN, UNEP, etc (thanks Hilary)said unequivacol and the politicians eco lobbyists said ‘the scientist is settled’ and ‘97% scientists agree’

    So where were all the scientist correcting matters?
    The silence of the scientists does them and scientific intergity a disservice

  39. it is certain that when it is warm it snows more and that cools earth
    it is certain the when it is cool it don’t snow much and earth warms.

  40. Here is my animation of the global mean temperature data

    http://bit.ly/ocY95R

    Note that when the offsets are removed, gistemp and hadcrut3vgl are nearly identical as shown below.

    http://bit.ly/nEUMsQ

  41. Congratulations on getting your paper into press! I have my own little section of a larger thing I’m working on . . . I avoid looking at the pile.

    I get less than passionately engaged with this aspect of the science, because it seems clear to me (I know you see it differently) that greater uncertainty creates a stronger case for action. If all we knew were two facts:

    1. Billions of people can live in the current climatic conditions (we know this is true, because we’re alive today).
    2. AGW will result, by the end of this century, in conditions which are warmer than any period since the invention of agriculture, and quite possibly warmer than any period in the last several millions of years.

    . . . that would be enough to conclude that BAU is not safe.

    But even though I would place your “uncertainty monster” behind us, spurring us on, as we approach the bridge to a low-carbon future, rather than under the bridge, a guardian to be overcome, I think better characterization of uncertainty is going to have nothing but positive effects on the science.

    • AGW will result, by the end of this century, in conditions which are warmer than any period since the invention of agriculture,

      That is just an assertion not based on the data.

      There is no evidence for that as shown below

      http://bit.ly/cO94in

      The global mean temperature then will be about the same as now, based on the 130 years pattern so far.

      • That is just an assertion not based on the data.That is just an assertion not based on the data:

        Fix’d!

        Neither Dr. Curry nor I believe in your magical, unphysical, all-explaining cycles. This is the science discussion, not AboveTopSecret.

        You seem very happy promoting this nonsense on WUWT. Why branch out here?

      • Robert

        Is your (IPCC’s) “accelerated warming” shown below based on science?

        http://bit.ly/b9eKXz

        The following interpretation of the global mean temperature is more rational

        http://bit.ly/ocY95R

        To talk of “accelerated warming” when the global mean temperature trend is decelerating is just environmental activism, not science.

        http://bit.ly/b9eKXz

      • To talk of “accelerated warming” when the global mean temperature trend is decelerating is just environmental activism, not science.

        http://bit.ly/kgchrg

      • Neither Dr. Curry nor I believe in your magical, unphysical, all-explaining cycles.

        Not knowing the mechanism of the solar system did not prevent farming before Copernicus.

    • Robert,

      We agree! Better characterization (and I would add ‘accounting’ and/or ‘disclosure’) of uncertainty is a good thing.

      I think it safe to say with way the climate change debate and energy production is evolving, we are not going to be BAU by the end of the century. Improving how uncertainty is included in the debate will enhance credibility on both sides, which could hasten agreement and focus attention on the areas where the most work needs to be done. I disagree we are heading for disaster, but I agree we have to change and are already changing the way we use and create energy for the better. Imagine where we might be by 2100.

      • I think it safe to say with way the climate change debate and energy production is evolving, we are not going to be BAU by the end of the century.

        If you think the climate change debate is evolving in such a way as to push us off a BAU pathway, do you think that is a good thing, or a bad thing? (Put another way: when you say you doubt we are headed for disaster, are you figuring the move away from BAU in your calculations?)

        It seems like you think the change is a good thing (“we have to change”). If that’s the case, what kind of change do you want to see? Do you think the change will emerge spontaneously from the market (i.e., no significant tragedy of the common effect) or are we going to need collective political action of some kind?

      • John Carpenter

        I believe the debate is evolving in a way that BAU is being ‘pushed off the pathway’. I see this as a good thing. I believe this is happening for a number of reasons. The need to change energy production benefits western society by moving away from the ‘middle east’ energy sources for security reasons. The change is coming from a more conscience public that does have concern for the environment, whether it is pollution or climate change or general environmental stewardship driving it. I think the market will drive this… energy companies (big oil) realize there is a shift in public sentiment about how our energy is made, you can see it in their marketing. They don’t want to be seen as ‘evil’. They will have to back up their rhetoric by improving efficiency and extraction as well as offering alternatives in the future. A number of alternative energy sources are being experimented with. We are at the beginning of this new area, so it may seem to be coming about slowly, but I am working on a number of alternative energy projects, they are out there. I simply don’t see how government or ‘collective political action’ as the answer to moving this ball forward. This is an authoritarian approach that will continue to get backlash and polarize the issue. I want to see a movement toward more nuclear energy and continued progress in engineering local alternative energy sources where it works all in an effort to slowly ween ourselves from fossil fuels. I fully believe fossil fuels are needed and will be used in the next 50 to 70 years to make this transition.

        Those are my thoughts FWIW.

    • Robert,

      More uncertainty provides a stronger case for action, when

      1) the addition is symmetric or more on the high end of risks

      2) the uncertainty concerns the risk of no action rather than the influence of action.

      In the real world some of the largest uncertainties concern the influence of proposed acts. We have both the possibility that the acts have practically no influence and the possibility that the acts have side effects that are worse than their positive results. This kind of uncertainties are certainly weakening the case for action.

      It’s not enough to say that we should aim for low carbon future. What’s needed are real implementable acts that are effective towards reaching the goals and without too severe side effects. Declaring goals and applying wishful thinking is not likely to be sufficient or even any significant value.

      • In the real world some of the largest uncertainties concern the influence of proposed acts.

        That’s your assertion. What is your evidence for it?

        We have both the possibility that the acts have practically no influence and the possibility that the acts have side effects that are worse than their positive results.

        1. There is very little uncertainty that cutting greenhouse gas emissions will slow climate change. A lot of basic physics would have to be wrong for that to be the case.

        2. The idea that measures that cut greenhouse gas emissions will “have side effects that are worse than their positive results” is not independent from the risk that rapid climate change will do great harm. If it will, it is extremely unlikely that a measure like a carbon tax will have a net negative effect. If the “wishful thinking” of lukewarmers pans out, and it won’t, it is possible that it will have a modest net negative effect. Since the uncertainty only comes into play if the risk from BAU is small, it’s not going to affect the calculation significantly.

        It’s not enough to say that we should aim for low carbon future. What’s needed are real implementable acts that are effective towards reaching the goals and without too severe side effects. Declaring goals and applying wishful thinking is not likely to be sufficient or even any significant value.

        It’s not enough to promote the “wishful thinking” that a planet warmer than the one we’ve lived on for the entire course of recorded history will be safe. Nor is it useful to invoke vague, unspecified “severe side effects.” What side effects?

        The meaningful uncertainty concerns “the risk of no action.” That is the only uncertainty which pertains to the ability of our climate to allow us to provide food and shelter for nine billion people. The uncertainty involved in minor changes to the tax code or mandated changes in power production or spending on public works — all common undertakings, all readily reversible — is not meaningful.

      • Unfortunately your first premise is false, namely that “1. There is very little uncertainty that cutting greenhouse gas emissions will slow climate change.” If this were true we would not be here debating it.

      • So your unspoken major premise, then, would be:

        1. There is no one who debates things that are well-established.

        Is that premise valid? I do not think that it is. There are still significant numbers of people who debate whether the earth is older than 6,000 years, whether humans landed on the moon, and whether aliens crashed at Roswell.

        This debate may or may not be comparable to those debates; we disagree. But the fact that a question continues to be debated does not prove, it seems to me, that significant uncertainty exists with regards to that question.

      • That is not my premise at all, Robert. (Stop trying to be a logician, as you have no skill there.) The nature of the climate change debate itself proves that your premise is false. A lot of bright, knowledgeable people question your claimed certainty. The refutation of your claim is thus very specific. In fact the message traffic on this blog is sufficient to prove you wrong. Your claim is absurd in the context of this traffic.

      • Stop trying to be a logician, as you have no skill there.

        Do you really want to start with the sniping?

        That is not my premise at all, Robert.

        You said:

        If this were true we would not be here debating it.

        In which “this” appears to refer to my first point: There is very little uncertainty that cutting greenhouse gas emissions will slow climate change.

        So we could rephrase your assertion as follows: If there were very little uncertainty that cutting greenhouse gas emissions will slow climate change, we would not be here debating about it.

        Since you do not suggest that the people debating here are exceptional in their insight, you claim is seemingly that:

        If there were very little uncertainty that cutting greenhouse gas emissions will slow climate change,[people] would not be [] debating [] it.

        The nature of the climate change debate itself proves that your premise is false. A lot of bright, knowledgeable people question your claimed certainty.

        Of course I didn’t claim certainty; you’re exaggerating. You did not say anything about “bright, knowledgeable people” before, so let’s update the claim:

        If there were very little uncertainty that cutting greenhouse gas emissions will slow climate change,[smart people] would not be [] debating [] it.

        Is that your claim? Smart people are never clearly in the wrong? Never deceive themselves? Never rationalize beliefs to which they have become attached?

        I’m not persuaded.

      • “Cutting greenhouse emissions” is rather a goal than an act. That requires some specific concrete acts or policy decisions. There are no non-controversial concrete choices to cut greenhouse emissions without significant side effects. Many of the proposed concrete acts have highly uncertain value. All policy decisions are controversial.

        Those concrete decisions that are essentially guaranteed to be without major side effects are inefficient in reducing the emissions.

        Recent years have taught us that nobody can predict, how economy will react to acts of the scale that are needed to make a real effect in the CO2 emissions.

        We have also a lot of experience (mostly with bioenergy) that acts that appear on first sight to be beneficial for the climate have indirect effects that negate the supposed reductions in CO2 emissions. Something can certainly be done, but anything of the required scale involves really large uncertainties.

      • “Cutting greenhouse emissions” is rather a goal than an act.

        Sure. So you have two distinct sets of uncertainties — uncertainties that affect our goals, and uncertainties that affect the optimal strategy for achieving those goals. And you seem to be saying that you have to reduce the second set of uncertainties before we can agree on the goal. That doesn’t seem logical. If the uncertainties are such that we can identify a clear goal, then we should identify the goal. Then we can weigh different sorts of action and the uncertainties there.

        Recent years have taught us that nobody can predict, how economy will react to acts of the scale that are needed to make a real effect in the CO2 emissions.

        ?

        How does a garden-variety recession prove that?

        Those concrete decisions that are essentially guaranteed to be without major side effects are inefficient in reducing the emissions.

        Like what?

        There are no non-controversial concrete choices to cut greenhouse emissions without significant side effects.

        The existence of controversy is an incredibly poor guide to whether a proposed idea is good or bad. The theory of evolution is highly controversial — that doesn’t mean that we should delay updating antibiotic recommendations until we all agree, with controversy, that the bacteria targeted have evolved resistance to existing treatments.

        We have also a lot of experience (mostly with bioenergy) that acts that appear on first sight to be beneficial for the climate have indirect effects that negate the supposed reductions in CO2 emissions. Something can certainly be done, but anything of the required scale involves really large uncertainties.

        We need not centrally plan large-scale interventions; a carbon tax puts the market to work discovering and implementing the most efficient means to reduce carbon emissions. “Side effects” would be discovered and worked through by investors testing different means of increasing their profits by reducing emissions.

      • A carbon tax will do nothing but line the pockets of insiders.
        Robert,
        Your assertion that you won and that Steven lost is the Black Knight’s fallacy.

      • Robert and Pekka

        Pekka has written:

        “Cutting greenhouse emissions” is rather a goal than an act. That requires some specific concrete acts or policy decisions.

        This is 100% correct.

        And there have been no specific actionable proposals to date that would have a perceptible impact on global warming by 2100.

        None.

        Max

      • Cutting greenhouse emissions is rather a goal than an act

        I’d say this was a dangerous line of argument. If generally accepted where would it end? No-one would ever act to do anything. Instead there would be a lot more nebulous waffle about goals, mission statements and where we expect to see ourselves in five years time! If an alcoholic middle aged overweight chain smoking drug abuser “acted” promptly on the sort of advice he might receive from any competent GP, there may well be some hope.

        If not, if the advice was just taken to be another “goal”, to be written at the bottom of a lengthy “to-do” list, or considered for some future new year’s resolution, then I’d not give much for his chances

      • Any argument can be dangerous when misused.

        It may be dangerous to not react. It may be more dangerous to react, but do that in a wrong way.

        The problem with climate policies is that no effective working policies are known. Proposals have been made, Kyoto protocol has been reached and several countries have followed it, but it’s real value is questionable as it’s difficult to find out, how the present is different from a counterfactual alternative. Some people have found strong effects, but those conclusions are based on questionable arguments.

        Living in Europe I follow policy decisions of EU and I really don’t like them. Several of the decided or proposed requirements for renewable energy or energy saving are formulated in a way that lead to totally stupid outcome, i.e. to an outcome that’s far from the optimal way of the reaching the ultimate goal and that also brings serious risks of health problems true questionable and poorly tested changes in building practices.

        EU has taken the approach of trying more than can be done. That’s guaranteed to backfire in couple of years with unpredictable consequences on the longer term development.

        I’m for a modest carbon tax, and my “modest” may be more than modest on the scale of some others (something like $20/ton-CO2 is the level that I have in mind). My view is that such a carbon tax is a much better solution than the cap and trade solution of the Kyoto agreement, which EU is planning to extend with tighter goals in future. Many more countries should join the same approach to make it effective and workable in longer term, but agreeing on that appears to be impossible in near future. Many more doesn’t mean all, but EU alone is far too small part of the world.

        Judith has emphasized often the need for robust solutions, I’m all for that.

      • Pekka Pirilä | September 12, 2011 at 4:33 am | paraphrased and appropriately distorted …

        … Any argument sophistry can be dangerous when misused. …

        That’s how it is with forceful, cleanly etched, decisive ‘description’. The strength and advantage is also the limitation and weakness.

        Difficult to escape dying by the sword when a person lives by the sword

        … Not easy to back away and reacquire scale and perspective either. Old soldiers have difficulty quitting their former profession.

        :-|

      • Once again, first at Lucia’s where your arguments were beat to a pulp and you left, and now here, you continue to misrepresent what the Lukewarmer position is. Let me make it clear. There is no consensus lukewarmer position on policy. No position. There are various approaches to policy that we suggest. But first and foremost the Lukewarmer position is this.

        1. GHGs cause warming
        2. man is increasing the amount of GHGs in the atmosphere.
        3. we think, sensitivity is more likely (51 to 49) to be less than 3.2C.
        4. Code and data should be free and open. Debate is good.

        That’s it. Nothing about wishful thinking or policy.

        no cookie.

      • “Once again, first at Lucia’s where your arguments were beat to a pulp and you left . . .”

        Steven, no matter how you beg, you can’t have a rematch. You got whipped. It’s over. Obviously it still upsets you a lot. But it’s not my problem.

      • Steven Mosher,

        I’ll do ya one better. Deniers, Skeptics, Lukewarmers and Warmers all agree the science is uncertain. The differences from there are all politics.

        Andrew

      • “The uncertainty involved in minor changes to the tax code or mandated changes in power production or spending on public works — all common undertakings, all readily reversible — is not meaningful.”

        Any collective effort that would have you as a supporter should opposed. It’s hard to believe your ilk have been left so close to the controls at all.

        You are clueless, no uncertainty in that evaluation at all.

        Stupid stick #101;

        “There is very little uncertainty that cutting greenhouse gas emissions will slow climate change. A lot of basic physics would have to be wrong for that to be the case.”

        How about no working real world models? No real world evidence or experiments?

        Thousands of qualified scientists no less “basic physics” than you??

        Think about how dumb you sound, for once.

      • Declaring goals and applying wishful thinking is not likely to be sufficient or even any significant value.

        Sure –

        And by the same token – saying that the presence of uncertainty in and of itself is an argument against action has no significant value (not to imply that is your argument) – particularly when arguments about the risks of action, in themselves, are based on enormous uncertainties that are, arguably, less quantifiable scientifically (because they are rooted in the vagaries or human behavior, ideological perspective, etc.) than the physics of climate change.

        IMO – Problems arise when expectations with respect to quantifying certainty are asymmetrically applied. Similarly, problems arise when uncertainty is exploited to justify ideological orientation towards the debate. Uncertainties will always exist, and quantifying uncertainties is of utmost importance; unfortunately, however, uncertainties are being viewed as tools for partisan aims rather than as variables that need to be quantified.

      • Declaring goals and applying wishful thinking is not likely to be sufficient or even any significant value.

        This criticism didn’t make a lot of sense to me. Obviously we have to agree on some goals before we evaluate possible strategies for achieving those goals. Do we agree on the goals? Talk about your wishful thinking.

      • Not to speak for Pekka, but I understand his point correctly –

        I agree that serious consideration needs to be made to comprehensively examine practicalities and logistics. I would doubt that he thinks that there is widespread agreement about goals at a detailed level, or that strategies shouldn’t be evaluated.

        The main problem, as I see it, is a rather pervasive resistance on both sides to disavow and control for tribalistic influences in how goals, practicalities, and logistics are evaluated.

        That said, I think that often that resistance comes in the form of exploitation of uncertainties to justify goals that lay beneath the surface. In that sense, motivating goals need to be more accurately and openly identified and discussed. Agreement on goals is obviously going to be extremely difficult – but yes, without an attempt to reach agreement, I think that more than likely all we’ll see is a continuation of the junior high school cafeteria food fight.

      • Sorry – that post should have read “if” I understand his point correctly.

      • Sorry – that post should have read “if” I understand his point correctly.

        It does sound more humble that way. ;)

        I agree that serious consideration needs to be made to comprehensively examine practicalities and logistics.

        I think the best way to get information about “practicalities and logistics” is too experiment, and the best way to experiment is to unleash the creativity of the free market on the problem. That brings me back to a carbon tax.

        The major logistical issues I can see with that are:
        * How do we verify taxable emissions.
        * How do we measure and verify offsets.
        * How do we discount partial offsets, such as (for example) a project that sequesters carbon in the ocean such that it slowly escapes over several centuries?
        * How do we extend the carbon tax model to encompass all the major producers in a binding international treaty? What carrots and sticks can we/should we bring to bear in that effort?
        * Should an international carbon tax take into account different stages of development? Should we, for example, index the tax to per capita GDP?

        I still don’t understand what Pekka is getting at. If we come up with clever solutions for logistical issues, the solution will be more attractive to those that don’t believe global warming is happening and categorically reject any and all taxation as an abuse of their human rights? That doesn’t seem likely. You don’t always have to agree on the problem to discuss solutions, but it this case it seems to me that you do.

      • to experiment” [blush]

      • Robert,

        If reducing the CO2 emissions to a really significant extent would be easy, we would have many alternatives in reaching that including a low enough carbon tax to avoid disrupting the economic processes. Unfortunately it’s far from easy. To reach really significant results by carbon tax, the tax would need to be very high. That might disrupt the economy severely. That could mean that among other things also the economic basis for developing good solutions for future reduction of CO2 would be disrupted and after a couple of years the situation could be worse even concerning CO2 levels.

        Other possibilities include forcing transition to solutions that have no future leading again just in loosing time, or they may mean wasting money in technologies that produce only 10% of the results the spending should bring, as the German investments in solar panels has done. We cannot afford real results, if we waste money like that.

        What’s really needed is a set of policies that avoids all serious pitfalls, keeps economy healthy (and I don’t mean maximal growth, but healthy in much more general terms), allows for finding really working solutions before they are implemented on full scale, etc. If the tighter requirements for CO2 reduction are even half true, we really don’t have the means to reach those goals, the means must be developed before they can be implemented. Any strong decision made on short notice is likely to be a bad decision.

      • To reach really significant results by carbon tax, the tax would need to be very high.

        I think you are in need of some evidence to support this assertion. It seems pretty dubious, and a good example of the “wishful thinking” characterizing people who want to prevent any action. But it certainly qualifies as an area of uncertainty.

        There’s an easy fix. Institute a modest carbon tax and see what happens to emissions over ten years.

        Other possibilities include forcing transition to solutions that have no future leading again just in loosing time, or they may mean wasting money in technologies that produce only 10% of the results the spending should bring, as the German investments in solar panels has done. We cannot afford real results, if we waste money like that.

        Oh, I don’t know, that sounds nice, but I’d also like to see some evidence for the assertion that “We cannot afford real results, if we waste money.” Today is the tenth anniversary of a war on terror on which we have spent some $2 trillion with another $1 trillion in expenses to come, mostly on two land wars in Asia, which were of very dubious benefit to America’s security.

        So a cynic might say we’ve wasted about $3 trillion dollars. Yet, we are still a very wealthy nation with an excellent standard of living. So while it is not a good idea to waste money, it is not the end of the world. That $3 trillion could have, at current prices, replaced our entire installed base of fossil-fuel electrical plants with nuclear power. The most efficient solution? Maybe not. For the most efficient solution, put a carbon tax in place and step back. But we could spend $3 trillion — remember, we just did — and still be a rich country. And we’d see more benefit from those plants than we did from the invasion of Iraq.

      • Robert –

        I think the best way to get information about “practicalities and logistics” is too experiment,

        OK – I agree with that…

        and the best way to experiment is to unleash the creativity of the free market on the problem.

        I’m not sure where the evidence is that lays out that case. There are many practical and logistical difficulties in societal level problems that are not solved by experimentation in the free market. You spoke of our interstate superhighway structure elsewhere in this thread. Free market creativity did not solve that problem. Certainly, I don’t believe that top down government solutions work in all or even very many cases, but in the least, in some situations, public/private partnerships are the most expedient form of experimentation.

        That brings me back to a carbon tax.

        And here I think that you make quite a leap. Even if free market experimentation were the best approach to the question of CO2 emissions, I haven’t seen convincing arguments – that deal comprehensively with myriad uncertainties in all directions and at scientific, economic, political and moral levels – to go from “experimentation is needed” (which I accept), to “carbon taxes are needed” (of which I am unconvinced).

        I personally tend to lean towards carbon taxes applied such that those who can most absorb the costs can fund the required research (through public/private partnerships) to explore alternative energy sources – but I am well aware that such a “belief” needs to be subjected to a scientific cost/benefit analysis. The problem is, however, that there are relatively few people who are doing cost/benefit analysis that aren’t driven by a partisan perspective.

        If we come up with clever solutions for logistical issues, the solution will be more attractive to those that don’t believe global warming is happening and categorically reject any and all taxation as an abuse of their human rights? That doesn’t seem likely.

        Now here I agree again. The problem, IMO, is that people are approaching the questioning of uncertainty without a full effort to control for varying political influences on the debate. There are some people involved in the debate who will simply never accept any form of taxation as a solution, no matter how comprehensively such a solution is subjected to scrutiny to quantify uncertainties. That, IMO, does not necessarily invalidate the validity of their view on taxes – but it does make the quantification of uncertainties of the science or uncertainties in the logistical or practical outcomes of carbon taxes irrelevant to their arguments. No matter how much they might try to justify their arguments on the basis of the presence of uncertainties, what lies beneath those justifications is their starting orientation and philosophical/ideological viewpoint on taxes independent of context – and all that follows is nothing other than “motivated reasoning” vis-a-vis the climate debate.

      • “…arguments about the risks of action, in themselves, are based on enormous uncertainties that are, arguably, less quantifiable scientifically (because they are rooted in the vagaries or human behavior, ideological perspective, etc.) than the physics of climate change.”

        This does not follow at all. The primary point of the climate consensus is that the planet has never experienced the increase in CO2 by anthropogenic sources that is now under way. We have no experience with the effect of a modest increase in the total amount of a trace GHG in the atmosphere on global average temperature, let alone its effects on local weather. The uncertainties are huge.

        On the other hand, we have had extensive experience with central planning of economies on a national scale, all of which have ended dismally, though some take longer than others to disintegrate. There is no real uncertainty in the belief that decarbonizng the global economy will have drastic negative effects world wide. (Not even Michael Tobis denies this. The claim of the CAGW activists is that those drastic costs are justified by the catastrophic damage they seek to avoid.)

        Now if you are limiting yourself to the effects of adaptation rather than global scale mitigation (AGW), you might have an argument. But that is not the argument at the heart of the climate debate (CAGW).

      • On the other hand, we have had extensive experience with central planning of economies on a national scale, all of which have ended dismally, though some take longer than others to disintegrate.

        1. Placing a tax on something we want to discourage is not “central planning” unless you want to redefine the term so broadly that it become essentially meaningless. If carbon taxes or alcohol taxes or cigarette taxes are “central planning,” then jaywalking laws are totalitarian.

        2. It’s a good example of a non-falsifiable argument to claim “all of which have ended dismally, though some take longer than others to disintegrate.” I might propose that all candidates for public office cut off one leg. I will advocate for this by arguing that “we have had extensive experience with representation by two-leggeds on a national scale, all of which have ended dismally, though some take longer than others to disintegrate.”

        All societies and all policies and decisions and most lives end dismally, some taking longer than others, of course. That’s entropy for you.

        3. If something as simple and decentralized as a carbon tax puts us on the road to “disintegration,” then presumably the United States was doomed long ago, when it built a vast system of interlocking highways under federal direction, for example, or when it created a federal agency empowered to deliver mail and parcels.

      • Robert

        ‘1. Placing a tax on something we want to discourage is not “central planning” unless you want to redefine the term so broadly that it become essentially meaningless. If carbon taxes or alcohol taxes or cigarette taxes are “central planning,” then jaywalking laws are totalitarian.’

        Laws are intended to protect people from other more brutal or ruthless people. Thus pollution, child labour, occupational health and safety – as well as the usual laws on murder, robbery, etc and many other such laws – can be justified as protection of the populace.

        Laws on alcohol and cigarettes aim to protect the populace against themselves – and are very much more difficult to justify where there is a component of the tax that is meant to reduce demand rather than just to recover costs.

        All laws are by definition central planning – they limit freedom by consent in a democratic society. We are not free to murder someone without risking state organised retribution.

        Carbon taxes impose ‘substantial costs associated with climate mitigation policies on developed nations today in exchange for climate benefits far off in the future — benefits whose attributes, magnitude, timing, and distribution are not knowable with certainty. Since they risked slowing economic growth in many emerging economies, efforts to extend the Kyoto-style UNFCCC framework to developing nations predictably deadlocked as well.’

        We are quite entitled to withhold consent to carbon taxes- as I most emphatically do.

        ‘2. It’s a good example of a non-falsifiable argument to claim “all of which have ended dismally, though some take longer than others to disintegrate.” I might propose that all candidates for public office cut off one leg. I will advocate for this by arguing that “we have had extensive experience with representation by two-leggeds on a national scale, all of which have ended dismally, though some take longer than others to disintegrate.’

        This of course is a logical fallacy. But the essence of our enlightenment heritage is individual freedom, private property, representative democracy and the rule of law. All other systems have ended very badly indeed with hundreds of millions of people dying in the bloodbath that was the 20th century. If this is your battleground – be prepared for irrelevance.

        ‘3. If something as simple and decentralized as a carbon tax puts us on the road to “disintegration,” then presumably the United States was doomed long ago, when it built a vast system of interlocking highways under federal direction, for example, or when it created a federal agency empowered to deliver mail and parcels.’

        There are certain services that a government might reasonably supply. Defence, education, health, water, sanitation, roads, etc. We may equally, in a democracy, not give consent to any or all of these. But carbon taxes are not even a service of any sort. They impose substantial costs on production – and this is the road to ruin for many people. You have to convince them that there is a benefit here. I think carbon taxes are fundamentally flawed technically – so you have lost one vote already. Your self imposed task is impossible – carbon taxes are dead politically. You may disagree – but hey that’s democracy.

        I suggest you read Hayek – The Constitution of Liberty and the Road to Serfdom – for a fuller understanding of the role of law and government in a free society.

      • Chief

        a) Don’t you only vote in Australia? If so, how do you matter?

        b) Hayek doesn’t say what you claim he says, if you’re claiming some support for your views over Robert’s in Hayek’s writings.

        c) Taxes that protect people from themselves generally only fractionally shift the responsibility for their decisions toward the consumers, who in becoming less valuable to the economy as a whole cost the Market, not just themselves.

        d) Protecting the Market is a valid use of government power, in particular where it reduces such tyrannical measures as prohibitions and bans, instead increasing the decision power of individuals by the mechanism of a meaningful price signal.

        e) Defining all laws as central planning betrays your central planning bias. America is built on laws, not central planning. Of course, you’re Australian, so it must be hard for you to imagine government that encourages people to decide things for themselves individually. In America you aren’t free to try to murder someone without the chance of facing their armed defense of themself.

        f) What exactly do you mean by substantial costs? The substantial cost of not having some centrally-planned over-capacity generating station built as a monopoly using scarce present resources to pay foreigners, who then leave, putting the immense and unnecessary facilities into the hands of a few corrupt unelected despots? Why do you support tin-pot dictators?

      • Robert,

        Surprisingly, I agree with you on your first point. If any tax is the equivalent of central planning, then the term becomes essentially meaningless. Like climate change.

        But that was not what I meant by central planning at all. The raison d’etre of the CAGW movement is not just a carbon tax (really a fossil fuel tax), but to decarbonize the global economy, and force the entire world to substitute more expensive, less efficient forms of energy for oil, coal and natural gas. A carbon tax, subsidies to favored eneregy industries, regulation of the users of energy (twisty lightbulbs anyone?), cap and trade, etc., etc. Now that is central planning.

        Your second point I disagree with entirely. First, you can falsify it by pointing to contrary examples. If there were any. Even progressives favorite socialist economy, Sweden, has been retrenching like a lemming who got a look over the cliff before he followed the crowd.

        Your counter example for instance can be falsified by any number of two legged politicians. Washington, Lincoln, Churchill. That is of course unless you expand the definition of fail to mean failure to achieve utopia, in which case it is you who is using a term in a way such as to render it meaningless.

        Your third point is a non sequitor for the same reason your first point is mistaken. No one is proposing “something as simple and decentralized as a carbon.” Would that that were so. The carbon tax is just the hump of the camel being driven into the tent, with the remainder of the nasty beast right behind (no offense to camels intended).

      • Bart.

        Again with the baffling non sequiturs.

        ‘a) Don’t you only vote in Australia? If so, how do you matter?’

        Gratuitous slander – we too vote for or against carbon taxes.

        ‘b) Hayek doesn’t say what you claim he says, if you’re claiming some support for your views over Robert’s in Hayek’s writings.’

        Hayak central concern in his later years was the limits to government. ‘A society that does not recognize that each individual has values of his own which he is entitled to follow can have no respect for the dignity of the individual and cannot really know freedom.’

        I was practically quoting Hayek – you are obviously clueless and just making noise again.

        ‘c) Taxes that protect people from themselves generally only fractionally shift the responsibility for their decisions toward the consumers, who in becoming less valuable to the economy as a whole cost the Market, not just themselves.’

        Weirdness – don’t smoke because it is an economic cost on society? I did suggest cost recovery.

        ‘d) Protecting the Market is a valid use of government power, in particular where it reduces such tyrannical measures as prohibitions and bans, instead increasing the decision power of individuals by the mechanism of a meaningful price signal.’

        Distorting the market for dubious ends with a cap and trade is a different matter entirely.

        ‘e) Defining all laws as central planning betrays your central planning bias. America is built on laws, not central planning. Of course, you’re Australian, so it must be hard for you to imagine government that encourages people to decide things for themselves individually. In America you aren’t free to try to murder someone without the chance of facing their armed defense of themself.’

        So every child carries a gun and you have no laws on murder? You are an absurd mountebank.

        f) What exactly do you mean by substantial costs? The substantial cost of not having some centrally-planned over-capacity generating station built as a monopoly using scarce present resources to pay foreigners, who then leave, putting the immense and unnecessary facilities into the hands of a few corrupt unelected despots? Why do you support tin-pot dictators?

        I provided numbers for Australia. Your rant is all heat and no light. Why do you persist in absurdities?

    • Robert wrote: I get less than passionately engaged with this aspect of the science, because it seems clear to me (I know you see it differently) that greater uncertainty creates a stronger case for action.

      What action? Greater uncertainty increases the likelihood that something will soon produce a change similar to the Little Ice Age. Should we immediately act to do the most possible to prevent both warming and cooling?

      • MattStat

        The argument for action is generally to curtail the external forcing.

        The external forcing acts as a perturbation on an ergodic system.

        While the next natural occurence of a drastic change at a tipping point is unpredictable, the odds of such a change being brought on by a perturbation may be expected to increase with the qualities of the perturbation.

        While we have so little information about the system and the perturbation that is CO2 increase, we’re blindfolded in a forest full of hornet’s nests, swinging a sharp stick wildly about our head.

      • Aren’t you describing something comparable to a slow manifold?

        Once the hornet’s nest is disturbed, no amount nor lack of further disruption shall dissuade the hornet’s nest from doing what the hornet’s nests does

        In the slow manifold, the equations of dynamic become degenerate, thereby dropping down to a reduced dimension or ‘manifold’ which is independent of the greater dimensional dynamic phase space from which it was derived.

        Having been decoupled from external forcing, the reduced dynamic space proceeds in it’s own sweet time and manner (usually verrrry slowly) unperturbed by parameters which were previously influential and encouraging of rapid evolution in the greater dynamic space from which this “now slow” manifold was formerly derived.

        Perhaps my explanation and understanding of slow manifold is wrong and flaky. I am unable to do better nor understand better. For that I apologize in advance.

      • Rav

        How slow do you think the hornets are, following the collapse of the nest, in that simplified manifold?

        Is the new and different unknown nest very slow to form, if it forms again? Sure. Could be.

        Or it may reappear instantaneously and for no apparent reason.

        Our ability to discuss ‘after’ the bifurcation is nonexistent, in terms meaningful to real world observers.

        Do we suddenly lose the ability to make weather predictions more than a handful of hours ahead of time?

        Gain the ability to predict weather for months or years as reliably as today we can do for a week?

        While we’re unlikely to see a reversal of the major ocean currents, what is the dominant arctic summer current in the absence of sea ice? Which could happen. Unless it can’t.

        What winds might become dominant in the new regime? Are arctic hurricanes worth discussing in this context?

        Is African desertification ending due AGW? Accelerating? Moving north or south or east, or skipping a continent? Skipping an ocean?

        The all-bets offness of the properties of the slow manifold is the question.

  42. With respect to the IPCC, Pachauri removed all doubt as to their ethical and scientific bankruptcy with his arrogant response (“voodoo science”) to the outcry concerning the bogus Himalayan glacier claim. At the very least, this should have given any fair-minded person pause. Dr. C. makes a great point concerning the next report. They will probably come up some sort of different format that does not allow for easy comparisons to be drawn with the previous.

    Either that, or they’ll just continue to go “all in.” Full speed ahead and damn the torpedoes. So far they’ve been able to distort the science, and make bogus claims of near certainty, with impunity. Of course, the alarmists have shown absolutely no willingness to use critical thinking, so no worries there. And from their perspective, who cares what the deniers say?

    Depressing as hell, but in my opinion it’s a waste of energy to hope that the IPCC is going to back off in the slightest. They really can’t.

    • My bet is that the IPCC will keep the same language (to change it would be to admit the AR4 was in error), but include a caveat is some obscure footnote – something to the effect that “levels of uncertainty are in dispute and, while they cannot be entirely precise, this is the best approximation of the vast majority of climate scientists.” Or maybe just an unexplained citation to some obscure paper dealing with the issue.

      What is important to the CAGW movement is the quote. Particularly in the summary for policy makers. Equivocation and CYA can be buried elsewhere in the AR5.

      The good news is that if the 2012 U.S. elections follow the current trend, the IPCC will become increasingly irrelevant, so it won’t matter how they massage their report.

    • With respect to the IPCC, Pachauri removed all doubt as to their ethical and scientific bankruptcy with his arrogant response (“voodoo science”) to the outcry concerning the bogus Himalayan glacier claim.

      And a theory of climate change based on ad hominem arguments of this kind is less bankrupt? Seriously?

  43. .”.best approximation of the vast majority of climate scientists.”

    This is a nutshell is the most destructive lie of all. They all tell it, even the ANdrew Revkin’s of the world who I’m positive know better. When pressed, Revkin hides behind the word “potentially,” as in his recent claim that “the overwhelming majority of scientists agree humans are affecting the climate in a ‘potentially’ calamitous way.” One might just as well say that the overwhelming majority of physicians agree that jogging affects the heart in a potentially calamitous way. Yah, but….

    There are two groups of lay alarmists in my view. There are the “altruists” like Revkin who know there’s plenty of doubt, but justify everything on the basis of the precautionary principal. Then there are the truly benighted, those who just don’t know any better. They of course are in the majority. The trouble is that in the unlikely event someone in that second group does get a clue, he generally just moves to group No. 1.

    So there’s no getting to them, at least in the medium term. 5 more years of significant cooling will hurt their case. Even Revkin admits that. But it seems like a long wait.

    • We are cooling, folks; for how long even kim doesn’t know, but probably for longer than five years.
      ====================

    • There are the “altruists” like Revkin who know there’s plenty of doubt, but justify everything on the basis of the precautionary principal.

      Is there only one “precautionary principle”? I can think of at least 6:

      a. First, do no harm.

      b. Look before you leap.

      c. Don’t put your eggs in one basket.

      d. Don’t count your chickens before they hatch.

      e. Haste makes waste.

      f. There are always multiple threats to consider.

  44. Ice Retreats when it is Cold because it don’t Snow Much.
    Ice Advances when it is Warm because it does Snow Much.
    http://www.ncdc.noaa.gov/paleo/pubs/alley2000/alley2000.gif

    The Temperature of the earth is very Stable, especially during the most recent ten thousand years.
    This is what regulates the temperature of the earth: When the Arctic Ocean is frozen, it doesn’t snow much around the Northern Latitudes and ice retreats, albedo decreases and the equilibrium temperature of the earth increases and Arctic Sea Ice melts. When the Arctic Ocean is Thawed, Arctic Ocean Effect Snow covers the Northern Latitudes and Ice Advances, albedo increases and the equilibrium temperature of the earth decreases and Arctic Sea Ice Freezes.
    This cycle repeats over and over and adjusts itself to overcome any and everything that tries to unbalance the temperature of the earth. Something caused the Medieval Warm Period. This cycle came back with the Little Ice Age. Kick it and it will kick back!

    Warm Ocean Time with Low Arctic Sea Ice Extent is a Necessary and Desirable Part of the Stable Cycle.
    This is the time when the Snow Packs and Glaciers are rebuilt.

    • Gotta say I love your theory, Herman. Snow in summer, no snow in winter. Makes more sense than those other skeptic theories of climate change that get trotted out periodically.

  45. ” five more years of significant cooling ” Oh that must be why the Arctic ice cap is melting ? What are you talking about ?

  46. Do your own research. I’m not about to waste a beautiful Sunday trying to reason with the cognitively undead.

  47. “the cognitively undead” Brilliant ! Thank you.

  48. I had never heard of “ontic” uncertainty or “bootstrapped plausibility”..

    My favorite selection was the following:

    “Confidence in the climate models that is elevated by inverse calculations and bootstrapped plausibility is used as a central premise in the argument that climate change in the latter half of the 20th century is much larger than can be explained by natural internal variability (premise #1). Premise #1 underlies the IPCC’s assumption (AR4, Chapter 9) that “Global mean and hemispheric-scale temperatures on multi-decadal time scales are largely controlled by external forcings” and not natural internal variability. In effect, the IPCC’s argument has eliminated multi-decadal natural internal
    variability as a causative factor for 20th century climate change. Whereas each model demonstrates some sort of multidecadal variability (which may or may not be of a reasonable amplitude or associated with the appropriate mechanisms), the ensemble averaging process filters out the simulated natural internal variability since there is no temporal synchronization in the simulated chaotic internal oscillations among the different ensemble members.

    The IPCC’s detection and attribution method is meaningful to the extent that the models agree with observations against which they were not tuned and to the extent that the models agree with each other in terms of attribution mechanisms. The AR4 has demonstrated that greenhouse forcing is a plausible explanation for warming in the latter half of the 20th century, but cannot rule out substantial warming from other causes such as solar forcing and internal multi-decadal ocean oscillations owing to the circular reasoning and to the lack of convincing attribution mechanisms for the warming during 1910-1940 and the cooling during the 1940’s and 1950’s.”

    Can we have a sufficient confidence in the models that we can absolutely rule out the possibility of a “Little Ice Age” scale cooling in the next half-century or so?

    I thought that the writing style was even-tempered.

  49. Good news?

    President Obama reportedly read these words publicly on this 10th anniversary of the frightful events of 11 Sep 2001:

    “Be still and know that I am God!
    I will be exalted among nations.
    I will be exalted on Earth.” – Psalm 46.10

    Almost 40 years earlier in Oct 1962 the Cuban Missile Crisis [1] convinced less wise leaders in 1971 [2] to save the world from the threat of mutual nuclear annihilation by uniting nations to work together to stop global climate change. This unscientific charade continued hiding, avoiding or misrepresenting experimental evidence [3-6] for four decades that

    1. Earth’s climate has changed and is changing.
    2. The Sun has evolved and is evolving.
    3. Life has evolved and is evolving.
    4. The Sun is violently unstable.

    With kind regards,
    Oliver K. Manuel

    1. Khrushchev-Kennedy Letters (Oct 1962) http://www.historyteacher.net/HistoryThroughFilm/FilmReadings/Khrushchev-KennedyLetters-13Days.pdf

    2. “Deep historical roots of Climategate” (2011)
    http://dl.dropbox.com/u/10640850/20110722_Climategate_Roots.pdf

    3. “The demise of established dogmas on the formation of the Solar System”, Nature 303 (1983) 286
    http://tallbloke.files.wordpress.com/2010/01/swart-1983.pdf

    4. “Is the Universe expanding?”, J. Cosmology 13, 4187-4190 (2011).
    http://journalofcosmology.com/BigBang102.html

    5. “Origin and evolution of life”, . Modern Physics 2, 587-594 (2011)
    http://dl.dropbox.com/u/10640850/JMP20112600007_31445079.pdf

    6. “Neutron repulsion”, The APEIRON J., in press (2011)
    http://arxiv.org/pdf/1102.1499v1

  50. Congratulations on an excellent paper. It may ruffle some feathers, but the logic is impeccable and the message very clear.

    Max

  51. Despite a cogent and well written argument – there seems little hope for any deep recognition of ontic uncertainty. The reasons for this are touched upon in the synthesis of 90% certainty from data with much lower ‘levels of scientific understanding’. It is a process of keeping uncertainty at bay through an ongoing struggle to reject or incorporate anomalies.

    My own feeling is that non-linearity in Earth systems create a profound uncertainty – even as to the direction of global surface temperature.

    http://judithcurry.com/2011/09/08/extreme-measures/#comment-111380

    But this it seems is one of those anomalies that simply fails to register in the consciousness of the ‘cognitively undead’. As Kim keeps saying – the world is cooling. This creates an insurmountable difficulty for the warministas. One that bothers me not a whit. The world view of the warmistas is a package that includes the prospect of catastrophic warming and the adoption of taxes and charges that are ultimately about the limits to economic growth. It all fits neatly – and one is not possible without the other. I deeply distrust the ideology and political motives of these people.

    As I keep saying – the bottom line for the emergence of a global, human civilisation is the continued growth in energy and food resources by 3%/year this century.

    Much of the world is open to other avenues for radical advances in human welfare, environmental conservation, economic development and energy resources. It remains to be seen how much longer this warminista nonsense remains even marginally politically viable – and if we may then be able proceed to rational policy.

  52. Conflicting information on energy that powers the Sun, changes Earth’s climate, and sustains our lives [1-3] is a danger to National Security.

    The National Academy of Sciences was “established by an Act of Congress . . . signed by President Lincoln on March 3, 1863, . . . which calls upon the NAS to “investigate, examine, experiment, and report upon any subject of science or art” whenever called upon to do so by any department of the government” [1].

    Please join me in asking Congressional representatives to request a FULL and CANDID evaluation from NAS of conflicting information in [1-3], BEFORE approving more funds for government research.

    References:

    1. UN’s IPCC reports (1990-2007)
    http://www.nasonline.org/site/PageServer?pagename=ABOUT_main_page

    2. Super-fluidity in the solar interior: Implications for solar eruptions and climate”, JFE 21, 193-198 (2002)
    http://arxiv.org/pdf/astro-ph/0501441

    3. “Neutron repulsion”, in press
    http://arxiv.org/pdf/1102.1499v1

    The time has come to stop arguing and for Congress to ask NAS to fulfill its responsibility to find out if experimental data and observations have been misrepresented.

    Sincerely,
    Oliver K. Manuel

  53. Alexander Harvey

    Judith,

    Here is a relevant slide presentation by a statistician that works in the climate sphere:

    http://www.newton.ac.uk/programmes/CLP/seminars/120711401.pdf

    Assessing climate uncertainty: models, meaning and methods
    By Michael Goldstein
    Department of Mathematical Sciences,
    Durham University

    The first half is an internal assesment (models) the second half an external assessment (system/real world).

    I think that many may find his approach challenging, much of it is a technical overview of statistical methods and frameworks but here are some quotes from the more conceptual component (warning the they are out of order so please do not infer context):

    “Despite all the enormous amounts of very hard science that is being done, and the detailed knowledge that we are acquiring, I’m not sure that anyone is making a careful specification of best current judgements representing current knowledge yet. This is because scientists don’t think this way, nor do most statisticians, policy makers don’t know how to frame the right questions, there are no funding mechanisms to support this activity and it is hard (because different)!”

    “Best expert judgements” are those which are sufficiently well founded that the expert is not aware of any further calculations that could “feasibly” be done which would be judged to lead to substantially improved assessments. If a problem is important enough that the uncertainty analysis will have a large scientific, commercial or public policy implications, then best current judgements set a meaningful, rigorous standard for the analysis. It is a fair and important question for the expert to have to consider and reveal as to just how “second best” the declared judgements are.”

    “The question of whether the Bayesian analysis of a simulator does indeed represent the judgements of the expert, is, in a sense, uninteresting. If experts are too busy, too lazy or too uninterested in the problems, then they are always free to equate their beliefs with the results of the computer analysis, however flawed, faulty or misconceived they perceive the analysis to be.”

    “… the analysis that has led to this judgement has been sufficiently careful and thorough to support this judgement and sufficiently transparent that the reasoning, not simply the conclusions, can be understood and reassessed by similarly knowledgeable experts in the field.”

    It is by no means all as agressively put as that and he is being constructive.

    The seminar can be viewed here:

    http://www.newton.ac.uk/programmes/CLP/seminars/120711401.html

    Alex

    • Alex,

      I really like the presentation, perhaps that’s because I agree fully on the approach and it supports the claims that I have made on the impossibility of having anything genuinely better than the Bayesian approach. The presentation tells very clearly, why the Bayesian approach is difficult and why it doesn’t provide objective results, but it explains also, why no genuinely better alternatives exist.

      I found the second half of the presentation more interesting starting from slide 67. That starts with

      Basic principle: it is always better to recognise than to ignore uncertainty, even if modelling and analysis of uncertainty is difficult and partial.

      That’s a staring point that I have also used to defend the Bayesian approach. Many other approaches start by formally accepting ignorance, but proceeding then in a way, where the actual significance of both the ignorance and of what we know anyway, are not faced explicitly, but taken care by the methodology in a too rough way. The problem that I have we some of the approaches proposed by Judith is that they lose information that way have anyway and therefore make the uncertainty to be a bigger monster than it really is. Only a serious attempt to apply the Bayesian approach can tell more about the limits of uncertainty.

      Understanding the nature of the three stages listed on slide 98 is also very important in that approach. The main problem may then be in valuing the Stage 2. The whole IPCC approach is closely related to Stage 2. Understanding, what’s the value of, what the presentation calls a scientific Bayes analysis becomes important. The name scientific Bayes analysis is a bit questionable, but in a sense all scientific knowledge can be considered as outcome of such scientific Bayes
      analysis
      , although it may get gradually closer to the third stage of an objective Bayes analysis.

      • Pekka, I agree that a Bayesian approach can be very useful, more useful if the full range of probabilities are considered, of course. James Annan’s Bayesian with expert priors was a little simplistic, (simplistic is relative BTW, it confused the hell out of me at first), but useful in evaluating the range of estimates of climate sensitivity. The range of estimate evaluated though all had one common assumption, No probability of sensitivity less than zero. While that may be a small probability, it does exist. Doesn’t that impact the validity of the analysis?

      • The paper of Annan and Hargreaves has been discussed here quite a lot. After getting over one stupid confusion I found it quite revealing. I don’t think that they introduce all good arguments in their paper, but their expert prior has at least that justifiable property that its tail is S^{-2}, which means that the prior is non-divergent for feedback strength, which seems to be a reasonable expectation.

        I don’t think that excluding negative climate sensitivities is a problem, but assuming that there is an equilibrium climate sensitivity at all might be closer to a problem.

      • “I don’t think that excluding negative climate sensitivities is a problem, but assuming that there is an equilibrium climate sensitivity at all might be closer to a problem.”

        I can see that. My thinking was that by including the possibility of a negative sensitivity it would down weight the notion of an equilibrium sensitivity. In other words, show that all the dragon kings are not on the positive side.

      • Alexander Harvey

        Pekka,

        Here is not the place but I still have strong, hopefully pragmatic, but deeply cynical views on the selection of priors. Views that I realy ought to justify if I insist on being rude about it. It is my prejudice that the combination of expert opinion (density fucntion) with the same evidence (likelihood) that the expert used to form that opinion is unhelpful. In a field with so little independent information and so few independent views such contamination is to be looked for and punished. I am afraid that I see priors as a good place to confine prejudice safely away from evidence. If any non-prejudicial content of a prior can be separated out then it becomes a likelihood and if independent of other likelihoods it can be used to update in the Bayesian sense.

        It is my view that statistics is bedevilled with implicit assumptions and the Bayes helped us to find them. Even such elementary operations as the determination of confidence intervals are not immune (e.g. the t test relies for its validity on a judgement, a determination to assume its unstated (implicit) prior density function for model variance or a prior intention to apply a model variance to be assumed from the evidence, if we attempt to rely on the sample variance). Failure to make that judgement prior to sight of the evidence is problematical particularly if the experiment (20th century warming) can not be repeated.

        In the case of climate sensitivity, the result of an experiment (doubling CO2) that we haven’t and may wish never to perform, Bayes does help me in that he highlights my reliance on our subjective confidence in the selection and interpretation of models and how to update this by combining with indirect evidence commonly based on yet more models. In this narrow case I do find all attempts to assign “a” probability density unhelpful, misleading and intensely annoying.

        We may ultimately have to assign priors in order to drive the outcome. When we have the entire decision chain in place we can allow the necessity of achieving agreement on acceptable actions, desirable outcomes, and priors (our then current beliefs or prejudices) to influence just those beliefs, actions and outcomes.

        If you should like to refute this or simply discuss it, perhaps you can make room at your place.

        Alex

      • Alex,
        The unavoidability of priors is a big problem. As you stated, even such statistical analysis, where most people see no need for priors involves them. Often it’s indeed fully justified to do the analysis as if the priors would not be needed, as the implicit uniform prior in the variable studied works well enough, and as there are good reasons to believe that the prior is uniform enough over the limited range allowed by the empirical results.

        The case of climate sensitivity is an excellent demonstration of the fact that in other cases the choice of prior really matters and justifying some specific prior may be very difficult. I don’t like at all typical expert priors that are based on badly defined views of the experts. Nobody should participate as an expert in that process without full understanding of what he is doing, but I think very few “experts” really do understand that in the way a correct Bayesian approach would require.

        The expert priors may be based on earlier empirical data that is not considered explicitly in the new analysis, and it may involve theoretical arguments. I like the argument that climate sensitivity is influenced by feedback strength and that the prior distribution of feedback is unlikely to diverge at 1.0. Furthermore there’s empirical evidence that the climate is not totally unstable, which leads to the exclusion of feedbacks more than 1.0. Putting all that together we have a theoretical argument for the requirement that the prior in climate sensitivity must fall like S^{-2} or faster for large S as wrote in my above post. I present this as an example of, what a expert prior might include. The arguments used for that prior may be argued upon, and some other expert might disagree, but he should tell, why.

        Similarly the reasons for conclusions from earlier empirical data should be specified at some level and presented for discussion. I should be verified that the same data is not used repeatedly, and that no hidden unjustified assumptions are included in the prior at a level important for the results.

        This is certainly not easy, but hiding it is worse than facing it.

      • Alexander Harvey

        Pekka,

        I think that the sensitivity issue has arisen because we have become fixated with an unanswerable question. I cannot be sure but I suspect that given that we have 50-100 years of so-so historical data we might be able to answer the pertinent question of how to map a similar 50-100 years of linearly rising forcing into a rising temperature excess (above what was commited) curve over the same period and to do so with some confidence and without a very fat upper tail. As evidence accumulates so will the temporal reach of our confidence.

        FWIW the example (t test) I quoted does not seem to rely on a flat prior but a 1/sigma prior density for the model SD paramter. This, if I have it right, is bound up with sigma being strictly positive (or rather non zero with +x and -x being equivalent) and all values being positioned equivalently i.e. the mass to the left and right of all values should be the same e.g. infinite. It is a curiousity if I am correct, and if so perhaps not well known but it would be sound in the sense it is perhaps the natural prior for a strictly positive parameter with no preferred scale. On the other hand I may be wrong, I do wrong a lot these days but I am pretty confident in the Mathematics and have done the checks on Excel that I could think of.

        Alex

      • The t-test is a complicated case to discuss, because it involves also the basic assumption that the actual distributions are Normal. Looking at the distribution of SD is only one part of the prior expectations that affect the t-test.

        The 1/\sigma distribution is in a sense the nearest equivalent of uniform distribution for a variable bound to be strictly positive. It corresponds to a uniform distribution in log(\sigma), which is the natural choice, when all positive values are accepted, but not zero.

        The problems of unbounded distributions (and the 1/n distribution, which adds up to infinity) like the prior of SD in t-test are manifested also in the well known two envelope paradox.

      • Alexander Harvey

        Pekka,

        The two envelope paradox was not known to me, so thanks. It does show the trap that an initial failure to capture the main issue (that the sum of both quantities is defined as being fixed) can rapidly lead to an apparent paradox.

        I find it interesting to consider the situation when asked to choose from an infinitely increasing and decreasing ordered set where even knowing which is the increasing direction does not lead to an ideal choice or even a sufficent choice if one has specific needs and may result in no choice given inifinite greed. One knows that for a finite set one must choose either of the extreme envelpoes, but not so obvious is the decision given a semi-infinite set, if one believes in infinite divisibilty one should pick the one at the end, if one can find the end.

        Most fun I have had since vacationing at Hilbert’s Hotel.

        Alex

      • Alexander Harvey

        Pekka and Dallas,

        There may be an argument based on an assumption that the expected value of the balancing outbound flux (LW+SW) is a single valued function of the temperature and that it is suspected that the temperature may not be a single valued function of the expected flux e.g. snowball catastrophe which indicates that the situation is not symmetric between T and F, and that an 1/S^2 density is more natural than the symmertric 1/S.

        Alex

      • Alex,
        Since I don’t have a good command of the math, let me describe the system so someone with the time and talent can make it look pretty.

        The minimum albedo of the Earth system is roughly 28%. The maximum albedo is roughly 36-38%. Assuming the sun doesn’t do anything real crazy and we don’t get nailed by a comet, of course.

        At our current 30% albedo, warming is limited by a 2% increase in forcing. That what is nice about a water world. So climate sensitivity levels off as you approach the albedo limit.

        In a glacial period, the climate sensitivity is not much different than in an interglacial. Climate sensitivity levels off as the maximum albedo is approached.

        In between is the fun part. The thermal inertia of the oceans will stabilize climate variation up to a point. The Northern hemisphere controls the shorter term climate, the southern ocean thermal mass plays a stronger role in the longer term climate. Since ocean heat content data sucks, it is hard to tell what is going on now, but the southern oceans have been stable since circa 1996 and possibly on a slight continuing decease with the subdued solar cycle. A small reduction in solar forcing over a longer time will be first observed in the southern oceans. This change probably drives the longer term quasi-cyclic oscillations. Can’t tell for sure, nasty data and very small changes in temperature make it difficult.

        This to many implies a much higher climate sensitivity, but it ain’t necessarily so, it can be just a little non-linearity in climate sensitivity. Albedo feedback in the past drove the more radical changes and likely will in the future. I was going to continue my research into this theory, but my funding got cut due to my links to big tobacco. :)

      • Alexander Harvey

        Dallas,

        Justy to let you know I will reply today maybe tomorrow but at the bottom of the is page. I will have to think for a while.

        Alex

      • Alexander Harvey

        Pekka,

        Thanks for your thoughts, please excuse me from not commenting on them fully. I think I concur but I am concerned that I may have a very different interpretation of the concepts because I have a different interpretation of the terms. I like you, am troubled by his use of “scientific” and can ascribe little more to this than being an adjective describing the nature or practice of the sciences and scientists.

        I struggle to separate the informative part of my opinion or judgement from my prejudices. And what follows is nearly pure prejudice.

        I truly believe that the term “objective” is defined by his stage three. That it is likely no more than the current result of a an ongoing process. I suspect that mine is a minority view and that others believe that it must refer to and have some separate existence or reality. I do not exclude that possibilty but I find it neither necessary nor particulalry useful.

        He and Jonathon “Jonty” Rougier seem to be people that these climate scientists think should be listened too. I have watched a number of the seminars in that series and few were so well attended. Both of them are challenging and are trying to introduce some clarity of method and importantly terminology. I am a little doubtful that they will succeed but at least they are being listened too and hopefully with some purpose beyond fulfillment of a sense of duty.

        I think that the experts will find the process tough going and bruising for I can but see that they must address their own prejudices, their prior beliefs. I think that what they believe is not very informative but how and why they have updated their belief is. It is the quotient of posterior belief over prior prejudice that we might all agree on as the evidence.

        It is however important that we do not get lot in the spectacle of it all. Here I am troubled by those that might see the process as an opportunity for obscuration. If it is desired that the process become more transparent then the experts must be allowed the space necessary to work the process. This I suspect they will not be allowed. It is simply not in the interests of those that have the narrowest of prior beliefs or prejudices to have the evidence evaluated methodically.

        I find that I only get close to the evidential if I attempt to justify an opinon that I do not hold.

        Alex

      • Pekka, you quote: Basic principle: it is always better to recognise than to ignore uncertainty, even if modelling and analysis of uncertainty is difficult and partial.

        Sure, but then what is meant by “recognize”?

        In Bayesian inference, “prior information” is used as the justification for choosing a marginal distribution for a parameter in a joint probability model: there is no logical justification for doing that, and seldom any information by which to test whether the chosen marginal distribution is an accurate representation of anything in the shared world. Illogical and untestable assumptions are not a sound basis for guiding decisions or claiming knowledge. In practice, the most useful priors are those that confer good frequentist coverage proportions, the so-called well-calibrated or pragmatic priors. {Ask yourself, after computing the posterior distribution, do you still believe the initial assumption that the marginal distribution really is the prior? By assumption, it still is.}

        When Bayesians are required in open debate to provide some evidence in support of their priors, they usually cite estimated frequency distributions.

        Some nice recent references: F. J. Samaniego, “A comparison of the Bayesian and Frequentist Approaches to Estimation”, pub. by Springer.

        R. E. Kass, “Statistical Inference:The Big Picture”, followed by discussion, in Statistical Science, Vol 26, Feb 2011.

        Special Issue of Statistical Science, Vol 26, April 2011, devoted to applications of Bayesian inference.

    • Alex, thanks a ton for this link, i love it. I will do a future post on the expert judgment piece of this.

      • Alexander Harvey

        Judith,

        you are welcome. It is my prejudice that if presented in a balanced way almost everyone with strong commitments will hate it. I thought twice about posting on it at all on the basis that shining light on progress is a good way to harden positions against it at both extremes of opinion.

        Alex

      • Alex wrote: It is my prejudice that if presented in a balanced way almost everyone with strong commitments will hate it.

        Give a thought to the large number of people who do not have strong commitments, or not yet on a particular issue. We like to know, and to see demonstrated, that the people who have strong commitments have made thorough evaluations of all the evidence with respect to all of the options.

      • Alexander Harvey

        Hi,

        I have given them that thought before my original posting. It is my opinion that the most committed have already excluded the middle ground and will hate a balanced approach. I hope that the argument has to be taken to those that can be influenced by the anaylsis. That will I think be largely determined by the insistance of those in the middle to demand that their concerns are met. I suspect that the chances of that happening will be improved if both extremes are equally ticked off.

        To return your phrase I do doubt that those “who have strong commitments have made thorough evaluations of all the evidence with respect to all of the options”. That is my prejudice. If both extremes would be obliged to be transparent we might get somewhere better.

        I happen to believe that AGW is occurring and it could create many net loosers but also it could create some winners. That stance is part informed opinion and part prejudice, I try to minimise the latter and question the former. I have many prejudices which include the harm I perceive that has and is being done by the most vocal.

        No matter how strong my beliefs I should like to listen to the evidence and to try and do so with the concerns of those that do not share my beliefs.

        There is a lot of good stuff in that presentation and seminar video and I think that some of the scientists would not enjoy having to characterise just how they have formed and informed their opinions. I should like to see a bargain whereby they are more transparent and in return we more accepting of their opinons at least as far as the honesty thereof

        Alex

    • Pekka makes an excellent overall summary. I would only add that Michael Goldstein (and others in the same department) are studying the issue of rapid climate change in collaboration with others, including the Met Office:
      http://www.noc.soton.ac.uk/rapid/rw/

      See also the MUCM (Managing Uncertainty in Complex Models) website for more if you’re interested:
      http://www.mucm.ac.uk/

      • Alexander Harvey

        Martha,

        I hoped people would find this material interesting and also challenging.

        I had watched it before and came back to it via the MUCM end of the work as I have an interest in understanding the use of Gaussian Processes in the construction of emulators. He and others seem to be offering a one stop shop for useful statistical approaches to modelling.

        I hope that people will be open to the notion that uncertainty analysis is being addressed by the climate community and not a fringe activity indulged in by only sceptics and heretics.

        Alex

    • Alex, Thank you for the link. It looks very good.

  54. Crazy thread, great accomplishment, Dr. Curry. I’m on my third reading now.

  55. Even with symmetric uncertainty, the policy implications of greater uncertainty do not favor earlier and more mitigation. For very high sensitivity levels, the possibility of cutting emissions enough to prevent the feared climate outcomes becomes small–the amount that would have to be cut would cause worldwide deprivation. It is only for “Goldilocks” sensitivities–not too low to be not worth mitigating, not too high to be unsustainably costly to mitigate–does an activist policy make sense.

    Of course, Judith is arguing against that kind of bell-curve understanding of the uncertainty.

    • srp

      How do you define uncertainty as symmetric?

      Uncertainty almost always weighs policy in one direction only, for the simple reason that it inflates the cost of any option.

      Temperature sensitivity levels are immaterial to the value of timing of mitigation; it’s more important to consider sensitivity to external pertubations.

      As such, earlier mitigation is always preferred, as the cascading Risks associated with perturbation of a complex dynamical system inevitably exceed mitigation costs.

      Also, where do your assumptions of worldwide deprivation come from? The alarmist economic presentations of runaway costs of mitigation have zero substantive foundation, and appear in general to be simple accounting sheet extrapolations, with no more meaning than a Hollywood movie budget.

  56. srp,

    I agree with your approach. I agree that we need to consider likelihoods, consequences and levels of warming. However, I’m not sure your conclusion is correct. For starters, although I’m open to variations on these, I’d propose the following figures:

    Min Waming (degC) Likelihood (%) Consequence (1-10) Product
    1 90% 2 180
    2 70% 3 210
    3 50% 5 250
    4 30% 7 210
    5 10% 9 90

    So it could well be that AGW is worth mitigating against even if warming is on the low side of projected levels.

  57. Lost my formatting previously.

    Min Waming (degC) Likelihood (%) Consequence (1-10) Product
    1 ,,,,,,,,,,,,,,,,,,,,,,,,,,,,,90%………………… 2…………………… 180
    2 ………………………. 70% …………………3,,,,,,,,,,,,,,,,,,,,,,,,, 210
    3……………………….. 50%………………… 5……………………. 250
    4……………………….. 30%,,,,,,,,,,,,,,,,,,,,, 7……………………. 210
    5…………………………10%………………… 9,,,,,,,,,,,,,,,,,,,,,,,,,,, 90

  58. I see the thread is degenerating into a justification for carbon taxes. I am not in favour of carbon taxes. For me – a global carbon tax translates into higher energy and food costs for those who can least afford it – the 150 million who are ill-nourished and the 2 billion or so on the edge of economic viability. The costs of a tax sufficient to cause substitution is easily calculated in the Australian context. It is about $70/tonne of CO2 for energy – for transport it is much higher – but say $70/tonne. It is about 4% of the economy/year – but would be much greater in an economy where food and energy basics were a higher proportion of GDP. It would be quite immoral to place such an impost on the global economy.

    But my being in not in favour is not at all relevant. It is simply not happening. It is not a politically viable mechanism. Much less so as the world is refusing to warm – and seems very likely to continue to do so for a decade or three more. I think to deny the latter outright is to show little understanding of the nature and extent of natural variation.

    Assume that carbon taxes will never achieve widespread endorsement – and you won’t go far wrong. There are alternatives – such as those outlined here – Breakthrough Institute – climate pragmatism. If that doesn’t float your mitigation boat – so sad too bad.

    • Rob,

      You are right that any fixed dollar value payment becomes easily a problem for the poor. That applies also to international market prices of commodities and food commodities in particular. The rich can buy in a sense the nutrition out of the mouths of the poor. That’s also one of the problems of bioenergy – or any other economic influence on the use of arable land.

      • “The rich can buy in a sense the nutrition out of the mouths of the poor. ”

        Stick to the science doc. Facile class warfare comments are ugly no matter what your first language is. If you want to talk about rich people taking food out of the mouths of the poor, let’s talk about ethanol requirements imposed by rich Western greens pricing food stocks out of the reach of much of the world’s poor. Or we could talk rich Euro eco-socialists blackmailing poor countries into not purchasing genetically modified foods.

      • Pekka was discussing distortions of that kind – you really have no call to respond like that.

      • Gary:

        Do you understand what a “regressive tax” is??

        Roy Weiler

      • Roy Weiler,

        Yes, I know what a regressive tax is. And I know that when a regressive tax is passed, it is the politicians who are taking “nutrition out of the mouths of the poor.” A regressive tax does not by itself limit the supply of a commodity, it simply makes that commodity unaffordable to the poor. No one is buying it out of the mouths of the poor, the politicians are pricing it out of their capacity to pay.

        Supply can ultimately be impacted as demand falls, but that is a secondary impact and does not occur initially. The rich aren’t suddenly buying and eating more corn because progressive politicians have artificially inflated its price (and all other basic food stocks) with their idiotic ethanol mandates.

        The obnoxious framing I objected to gets it exactly backwards, but that was not why I commented. It was the class warfare phrasing.

        Roy, since you are defending the statement, perhaps you can explain your understanding of a regressive tax, and how it justifies such a comment.

        Chief,

        Of course he was “discussing distortions of that kind.” My objection was not to the subject matter, but how he chose to express it. And I stand by my criticism. It showed a reflexive adoption of class warfare rhetoric (apart from being wrong on substance).

        Pekaa is usually one of the most civil commenters on this blog. That does not make his comment any less objectionable.

      • I read it somewhat differently in that taxes (or cap and trade) that increase food costs are more a problem for the poor than the rich. Which is what I said and Pekka agreed to. Nothing to do with blaming the rich – just the ways it is.

      • ..which is where the other side of the equation comes in.

        You must also pay the fees levied on CO2 budget incursion to those who own the carbon cycle, per capita. (All of us.)

        That would remove the distortionate Market effects, and stimulate the Market to return to fair equilibrium. at which point it regains efficiency and the mutual interests of all participants in the economy are equibly balanced by the democracy of the Capitalist mechanic.

      • Bart,

        I have to respond because the impracticality of taxes (politically and economically) means that it is just an ongoing distraction from viable alternatives – although I know it is unwise.

        The proposition you’re advancing is that we can set up a global tax office. It is impossible. The other reality is that if these taxes worked – we would be left with higher cost energy and no tax revenue.

        Now before you go off again on an abusive and vacuous rant about taxes creating cheaper energy – stick it in your beanbag.

      • Chief

        Why do Australians think that just because their wealthier citizens can buy and sell US congressmen and senators that the average Australian (meaning yourself, Chief) gets a vote in America?

        When I discuss policy, tax, economics, the Market, etc., I of course refer to nowhere else but America, which, let’s face it, is all that matters.

        (Unless you count China, which invariably only counts as an argument from ignorance, as those who really know and understand China don’t tell their secrets.)

        And yes, I understand the impracticality of my proposal. Which doesn’t stop me, because America is all about making the impractical real.

        Look at Mel Gibson. Who would think it were practical to turn an out-of-work Aussie bigot into one of the most powerful men in the world? Hollywood thought it, and made it so.

        You should see what happens when the USA uses actual Americans for impractical missions.

      • Bart,

        Stick to your fantasy land, incoherent tax rants. Your anti-Australian comments are obnoxious and, fortunately, not shared by genuine American conservatives. Nor any progressives, moderates or independents that I know of for that matter.

        You are a minority of one in your Aussiephobia.

      • My point is related to the large differences between the official exchange rates and the purchase power parity exchange rates and to the huge difference in the value of one dollar for people who earn one or two dollars a day compared to those who have the income level of middle class Americans.

        Under such conditions all kind of distortions may come up, and my “The rich can buy in a sense the nutrition out of the mouths of the poor. ”, was only a condensed reference to that. As Rob (Chief) understood this is not a condemnation of any party, just an observation of the state of affairs.

        I’m certainly not a libertarian and quite possibly more on the left on the American scale, and I wonder often, how strongly the libertarian thinking is visible on the net. That’s true even here in Finland, where it’s almost impossible to meet a libertarian outside of the net. There must be some reason for the exceptional willingness of libertarians to express their views on the net. It may be related to the fact the libertarian thinking has a clear and simple logic, not broken by the fact that we non-libertarians believe that the logic doesn’t apply in the real world, but only in an idealized world that’s almost as far from realism than the opposite idealized world of communism.

      • Alexander Harvey

        Pekka,

        “… that the logic doesn’t apply in the real world, but only in an idealized world …”

        Welcome to the Internut. If you are looking for Libertarania, it is all around you in cyberspace. I more than suspect the existence of strong links between the libertarian and cybernetic dreams.

        Viewed in terms of Europe vs America, and Left vs Right, it is easy to lose sight of the breadth of libertarian thought that was once expressed. When young, I associated almost exclusively with people who were identifiably libertarian and many were at the sinistral extreme.

        I suspect, perhaps hope, that the far left libertarianism still lives on at least in Europe.

        What you describe as the simple logic springs from a simplified model, not of society but of the individual, particularly the ethical citizen hero. If we could all be like that then the best possible society would spontaneoulsy come to be. Everyone would be free, both “free from”, and “free to”.

        A dilemma of liberty is what to do with those that do not wish to be free. If it is clear that free people make for a better world then must one force them to be free?

        We could try to build a world fit for libertarian heroes but almost everyone else would hate it, or abuse it. Perhaps we have tried and it is has led not to anarchy but chaos.

        Alex

      • GaryM,

        Its not just corn and ethanol. Another example would be that in many African countries, local fish stocks, which were once the sole preserve of local fishermen, to be sold in local markets, have now been sold at much higher prices to the fishing fleets of wealthier countries.

        So, Pekka’s comment “The rich can buy, in a sense, the nutrition out of the mouths of the poor” seems fair enough to me.

        It certainly can’t happen the other way around.

    • I see the thread is degenerating into a justification for carbon taxes.

      Indeed. We’ve seen everything from the “using uncertainty to argue against any action” meme (the inference seeming to be that any action that doesn’t meet with the commenter’s approval is no action at all) to this: “There’s an easy fix. Institute a modest carbon tax and see what happens to emissions over ten years.”. The “see what happens to the economy” seems to get lost.

    • , I see the thread is degenerating into a justification for carbon taxes

      I would personally prefer a Cap and Trade system.

      However, lets see what other ideas people may have to ensure CO2 emissions are reduced. That’s what we are trying to achieve, and if it can be done without either, so much the better.

      • Why would you prefer a cap and trade system?

        I’m curious. It seems to me all the advantages are with a carbon tax. They both give you a carbon price, but as you succeed in lowering emissions, the carbon price in C&T goes down, because of the fixed supply of permits, while with a carbon tax it remains constant (as it should; the negative externality of the carbon emission are not going down.) A tax is more predictable, and hence more likely to attract investors who want to calculate the return on their dollar.

        Interested in why someone would prefer C&T.

      • Robert,
        Part of the problem with the idea of ‘carbon tax’ is that it is misnamed.
        It is a carbon penalty, not a tax.

      • tempterrain

        Would you prefer cholera or the bubonic plague?

        (Or maybe neither?)

      • Robert,

        There doesn’t have to be a fixed supply of permits under a C&T scheme. The number probably will need to be modified according to the nature of the scientific advice of the amount of CO2. This how it worked with the successful SO2 scheme. See for example: http://en.wikipedia.org/wiki/Acid_Rain_Program

        The problem with carbon taxes is that they aren’t as easily tradable, internationally. I’m not sure what you mean by investment in a tax. How does that work?

        It would be good if the choice was be between an effective tax or an effective C&T scheme, and I agree that both could work. But it looks to me that the choice at the moment is between doing little or doing nothing and that can be a depressing thought.

  59. Hi Pekka,

    We need better models for action than has been achieved in the past 15 years. One of the problems seems to be that the people most wanting action are the ones resisting an alternative paradigm. No agreement seems possible.

    Cheers

    ‘The old climate framework failed because it would have imposed substantial costs associated with climate mitigation policies on developed nations today in exchange for climate benefits far off in the future — benefits whose attributes, magnitude, timing, and distribution are not knowable with certainty. Since they risked slowing economic growth in many emerging economies, efforts to extend the Kyoto-style UNFCCC framework to developing nations predictably deadlocked as well.

    The new framework now emerging will succeed to the degree to which it prioritizes agreements that promise near-term economic, geopolitical, and environmental benefits to political economies around the world, while simultaneously reducing climate forcings, developing clean and affordable energy technologies, and improving societal resilience to
    climate impacts. This new approach recognizes that continually deadlocked international negotiations and failed domestic policy proposals bring no climate benefit at all. It accepts that only sustained effort to build momentum through politically feasible forms of action will lead to accelerated decarbonization. If this new era is to be led at all, it will be led primarily by example, not global treaty. The Copenhagen Accord is one of essentially voluntary actions among major emitters. The accord perpetuates the conceit that international negotiations will ultimately include legally binding emissions reduction targets, but in reality, the emissions targets will be unenforceable and thus constitute aspirational goals, not binding limits. That reality became even clearer at UNFCCC negotiations in Cancún in December 2010. The substantive parts of the Copenhagen Accord are the new multilateral agreements to invest in new energy technology, slow deforestation, and build disaster resilience — far better grounds for global cooperation than unenforceable emissions targets and timetables.’
    http://thebreakthrough.org/blog/Climate_Pragmatism_web.pdf

    • Rob,

      The original Hartwell paper and various texts of the Breakthrough Institute contain a lot of sense. My main disagreement with them is that they justify their own proposals with optimism in the approaches they promote, and I find that optimism ill justified.

      It’s the common problem that’s easier to criticize, what others have proposed than to present a genuinely better alternative.

      Your own staring comment is on the point. What we need is more open discussion on the alternative policies without too many preconditions and without unwillingness to replace something that’s not working with something totally different. I understand the unwillingness of many to give up on, what was achieved with great effort in Kyoto, but they should finally accept that being stubborn on that is only detrimental for the progress and also for their own ultimate goals. The Kyoto is a wrong way also for its serious technical weaknesses, not only for the difficulties in getting others to agree on it.

      • staring -> starting

      • I prefer your original post with “staring” instead!

      • Part of the problem is that, having talked themselves into believing that we only have 4 years (or whatever Prince Charles said we have left), the alarmist fringe has put themselves into a box where they can’t back down and talk rationally about something that must be a multi-decadal process. They’ve then put themselves into an even smaller box by taking nuclear off the table, and insisting that wind, solar, and conservation comprise a plan that can be pursued in 2011. Then they put themselves in an even smaller box yet by opposing bridge technologies such as shale gas. That’s our low-hanging fruit right now, in America and Europe – we can make a significant carbon reduction with minimal investment or new technology just by transitioning commercial vehicles from petroleum to compressed and liquified natural gas.

        Once you’ve painted yourself into a corner by insisting that you have to do something now, and then get in the way any time something new and practical comes down the road, there’s nothing left to do but keep doing what you have been doing, only louder. And here we are.

      • P.E.,
        You have summed up the non-rational side of AGW very well.
        The latest version of the AGW cacophony (caca-phoney?) is going to be Gore’s impersonation of the old Jerry Lewis MDA telethon, starting sometime tomorrow.

  60. I wish there were an open Climate Mitigation thread where all the related discussions would go to die.

  61. Re. this Curry/Webster paper.

    Since I’ve made specific comments elsewhere, I will only re-cap that I would encourage Curry, and apparently also Webster, to read relevant journals (e.g. philosophy of science, and science/logic/math) more extensively. The paper is unfortunately not as well-informed as it could be by a range of fundamental conceptual, epistemic and practical dimensions relating to the issue of uncertainty.

    We all understand that climate policy decisions are decisions made under uncertainty. There are also inherent uncertainties in engineering and I would say that some of the better engineering theory discussions on this site have been among the most informed among academic-oriented denizens, especially with respect to model pluralism and the characterization of the relative scientific, epistemic, and practical import of that approach.

    But we also need to get more benefit from some of the less sanitized discussions that integrate important and complex questions in theory and in applied science, with questions about values and cultural judgments. Questions about what is possible, and what is likely, need to be equally applied to the obvious problem of whether climate change is set to make rich people richer, and poor people poorer.

    Even if, for now, we choose to limit climate change policy to adaptation, pretty much none of the relevant discussion is occurring. What methodology and principles will guide it? sustainability principles? avoiding harm to someone else’s livelihood? whose? Etc.

    cheers

    • “we choose to limit climate change policy to adaptation”

      Adaptation central planning and social management wouldn’t even satisfy the hearty fringe at the center of the AGW movement as this attitude demonstrates.

      “Questions about what is possible, and what is likely, need to be equally applied to the obvious problem of whether climate change is set to make rich people richer, and poor people poorer.”

      Include class war euphemism for wealth redistribution purposes, blaming and hate, lovely.

  62. The National Academy of Sciences was established by an Act of Congress . . . to “investigate, examine, experiment, and report upon any subject of science or art” whenever called upon to do so by any department of the government.

    http://www.nasonline.org/site/PageServer?pagename=ABOUT_main_page

    Can you help develop this list of unavoidable questions so Congress can obtain information from NAS on today’s AGW controversy?

    1. The influence of CO2 on Earth’s changing climate is:
    a.) Large b.) Small c.) I don’t know

    2. The Sun’s influence on Earth’s changing climate is:
    a.) Large b.) Small c.) I don’t know

    3. The interior of the Sun is mostly:
    a.) Hydrogen (H) b.) Iron (Fe) c.) I don’t know

    4. The Sun is powered principally by
    a.) H-fusion b.) Neutron repulsion c.) Electricity d.) I don’t know

    5. Which publication (and references) is more scientifically credible
    a) IPCC reports b.) APEIRON report c.) I don’t know

    a.) IPCC reports: http://www.ipcc.ch/publications_and_data/publications_and_data_reports.shtml

    b.) APEIRON report: http://arxiv.org/pdf/1102.1499v1

    With your help, endless discussion can cease and integrity restored to science and government!

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

  63. A carbon tax is an attempt at a solution via punishment. Wrong policy. Second – we haven’t got a well defined problem. It is way too early to propose solutions for the simple reason we don’t know what we’re solving. The precautionary principle is founded in hysteria. It is not enough to say we must use the precautionary principle because it makes sense – we need to know that the alarmists make sense. Until the feedbacks and forcings are understood we don’t know.

    By the way – somewhere in our area of the universe there roams a killer asteroid that is on a collision course with our fragile blue world. We must expend every effort to find it and destroy it. Money is no object – the future of mankind rests on our invoking the precautionary principle. We cannot put this off! I propose a tax on every bank transaction made between banks only, and which is a percentage of the transaction on a sliding scale, going up in percentage as the size of the transaction goes down. There is a fixed floor of 3%. This is a fair tax that affects only the wealthy banks around the world and does not affect those individual tax payers on fixed incomes and who shore up the bottom of the economy with their minimum wage earnings.
    /sarc <– as if this is needed…

    • In the lingo of psychology, it’s “negative reinforcement”. And psych theory says that negative reinforcement often works, but tends to produce more unexpected side effects than positive reinforcement.

  64. With a “very likely” approach to truth it is not surprising that we find a consensus within government where so many believe the way to reach a fix the economy is to cut off the right hand of the productive who cause global warming.

  65. Congratulations, Prof. Curry…
    Two questions (not related):

    1. In Section 3.2 Reasoning about uncertainty, you have a sentence starting “The IPCC characterization of characterization is based upon a consensus building process…”. I’m wondering if this should be “characterization of uncertainty“? If not, I would put the second use of the word in quotes, or if I were blogging follow it with a “(Heh!)”. Not to mention I’m not sure what it means.

    2. While searching for something else, I ran across a paper titled “Is Global Warming Mainly Due to Anthropogenic Greenhouse Gas Emissions?” by Xiaobing Zhao of “The W. A. Franke College of Business, Northern Arizona University, Flagstaff, Arizona, USA“. I don’t have access, and probably wouldn’t understand it anyway, if it’s as technical as the abstract seems to promise. Is this a “Merchant of doubt“? If not, are you planning a discussion?

    • yikes, hard to imagine how that kind of error made it through after going over the paper so many times. I will try to find the Zhao paper, do you have a link?

      • I guess the paper is closely related to this older working paper

        http://www.cba.nau.edu/Faculty/Intellectual/workingpapers/pdf/Zhao_GHG_Emisions.pdf

        available from the University site.

      • Thanks, Pekka Pirilä…

        I’ll read it and try to guess whether it’s for real.

      • Well, it seems to be Primarily based on Lindzen 2007 (“Taking GreenHouse Warming Seriously” in Energy & Environment(http://www-eaps.mit.edu/faculty/lindzen/230_TakingGr.pdf)), so I’m guessing it’s one more waste of time. But I’ll keep reading.

      • Why would you bother to keep reading? You indicate above that you are not capable of understanding a technical paper. You also infer that you can decide who to believe based on their being labeled a “merchant of doubt”. I guess that means that you find the merchants of fear (or doom, alarm, whatever) more believeable even though they have a long history of being wrong.

      • Well, Dennis, reading the abstract I assumed (and you know what that does) some sort of statistical analysis of multiple climate model runs. What I got from Zhao(2009), which I assume is identical to Zhow(2011), is a ridiculous regression analysis of temperature trends against local CO2 emissions by US state, well within my ability to understand. For that matter, Lindzen(2007) is also within my ability to understand, although IIRC I never read it before because I normally skip over any paper that starts with an IPCC cartoon.

        While I’m not confident enough of my understanding of statistics to do a full critique of Zhao’s analysis, I know enough about climate science to know this paper falls right into the category of “Merchant of Doubt”.

        So does Lindzen(2007), as demonstrated by his ignorance of how EM absorption/emission works in a gas. I actually read the paper this time, although I had to keep from upchucking a few times. It’s a disgrace this paper was published, although I know of a few others in unrelated subjects that are just as silly.

        As for your “merchants of fear” nonsense, there’s a big difference between model runs published by people who admit their margins of uncertainty, and the IPCC’s “certainty”. I’m willing to believe Prof. Curry because she not only admits margins of uncertainty, but is pushing for the IPCC and other organizations to admit them.

  66. Looking at the numbers, the suffering of AGW alarmism will continue;

    http://wattsupwiththat.com/2011/09/13/brits-question-global-warming-more-than-americans-and-canadians/#comments

    A President Perry or similar will help on this issue but it will be a dangerous part of the eco-extreme for years to come. Even if the poll is cooked to a degree it’s disappointing how many remain bought in. These are somewhat educated countries.

  67. Dr Curry – Have you seen this new website http://climatecommunication.org/

    What is your opinion of it?

    From their home page

    “Climate Communication Is…

    …dedicated to improving public understanding of climate change.

    We combine expertise in climate science with excellence in communication”

    • Warmist/alarmist propaganda at our finger tips! What will they think of next?

      • The *newest* technique in “climate communication” = animated red colors.

        What will the experts think of next? Warmer Zombies disguised as climate scientists?

        Andrew

    • Louise,
      Perhaps they can provide sales tools to the ACE marketing enterprise?
      Gore’s video showing poop being flung at a fan represents the climatecommunication.org site goal very well. although the Goreons aimed the video at the skeptics, it is clearly an example of being hoisted by one’s poop-tard: The only group throwing s**t at the fan right now is the AGW promotion industry. Climatecommunication.org is just an example of this in action. But the video is more fun. ;^)

      • too bad they didn’t use a wind turbine as the fan.

      • I only wish I had the computer kung fu to capture the video and change the narrative part to make it clea that Gore is tossing his poop at the fan and hoping something will stick.
        Perhaps a performance art video of someone dressed as Gore, tossing cow pies at a large fan and capturing the flung excreta on some sort of canvas with the title, “GLOBAL WARMING THEORY”.

    • Who is “Climate Communication” and what are the organization’s mission, goals and objectives?

      CLIMATE COMMUNICATION IS…
      …dedicated to improving public understanding of climate change.

      We combine expertise in climate science with excellence in communication

      http://climatecommunication.org/

      “Excellence in communication” = good PR (propaganda)

      Climate Communication is a non-profit science and outreach project funded by the Rockefeller Brothers Fund and the ClimateWorks Foundation. Climate Communication operates as a project of the Aspen Global Change Institute, a nonprofit organization dedicated to furthering the scientific understanding of Earth systems and global environmental change.

      Aspen Global Change Institute (AGCI)
      Is an independent nonprofit dedicated to furthering the scientific understanding of Earth systems and global environmental change through interdisciplinary scientific workshops and publications & videos.

      How did the ClimateWorks Foundation start? Who was behind it? The ClimateWorks Foundation emerged from a study commissioned by six foundations: the William and Flora Hewlett Foundation, the David and Lucile Packard Foundation, the Energy Foundation, the Doris Duke Charitable Foundation, the Joyce Foundation, and the Oak Foundation. The 2007 study “Design to Win: Philanthropy’s Role in the Fight Against Global Warming” (pdf), sought to answer a critical question: What would it take to achieve a real “win” in the battle against climate change? The authors of Design to Win interviewed more than 150 of the world’s leading experts on energy, climate change, and forests to identify the top priorities for avoiding dangerous climate change. Using cost curves and other research, the Design to Win analysts ranked investments by their potential to reduce greenhouse gas emissions and their ability to prevent the “lock-in” of long-lived, carbon-intensive infrastructure. The ClimateWorks Foundation was built on the principles identified in the Design to Win study and launched in 2008 with the support of three foundations: the William and Flora Hewlett Foundation, the David and Lucile Packard Foundation, and the McKnight Foundation. (Learn more about the founding story of the ClimateWorks Foundation at: http://www.climateworks.org/about/our_history/)

      http://www.myphilanthropedia.org/top-nonprofits/bay-area/climate-change/climateworks-foundation

      From “Design to Win, Philanthropy’s Role in the Fight Against Global Warming ”, the stated manifesto for The ClimateWorks Foundation:
      design_to_win_final_8_31_07.pdf
      http://climatecommunication.org

      OUR CONCLUSIONS
      Our analysis yielded a short list of the initiatives with the most potential to set the world on a low-carbon path. Four overarching priorities orient our investment road map:
      First, don’t lose – the battle could be lost in the next decade.
      Catastrophic climate change – far worse than anything we have experienced – will be unavoidable if we don’t prevent a massive “lock-in” of emissions from new coal-fired power plants, long-lived industrial infrastructure, inefficient buildings, car-centric cities, and irreversible deforestation (Figure 1). The First Rule of Holes: when you’re in one, stop digging.
      􀂃 We must concentrate our efforts geographically. Global, collective action is critical for reducing the numerous drivers of climate change, but philanthropy must focus its efforts. Our search for substantial carbon reductions leads us to the U.S., E.U., China and India. The U.S. and E.U. – which are responsible for more than one-third of greenhouse gas emissions, both currently and cumulatively1 – must take the lead and pioneer new technologies. In China and India – where per capita emissions are one-sixth and one-thirteenth the U.S level, respectively – there is still time to influence energy investments and the shape of booming mega-cities, where the greatest mitigation potential lies. To address tropical deforestation, we must also look to remote jungles in the Amazon, Congo and Indonesia. Furthermore, when it comes to the critical task of putting a price on carbon, we should invest where national and international politics demand.
      􀂃 Policy reform is essential for tempering climate change. A cap on carbon output – and an accompanying market for emissions permits – will prompt a sea change that washes over the entire global economy. Putting a price on carbon will help spark innovation and the clean technology markets needed to prevail in the long term. The global community must overcome the collective action problems that have hobbled international climate agreements. But a carbon price alone won’t be enough to keep emissions in check for two reasons. First, more than 30 percent of essential mitigations will be more expensive than the likely carbon price. Second, low-carbon interventions are likely to be slowed by non-price barriers, such as perverse subsidies, principal-agent problems, counterproductive utility regulations, and inefficient channels for both information and investment in research and development. Sector-specific policies are also needed to complement carbon pricing.
      􀂃 Our interventions also must target five sectors that play a leading role in greenhouse gas emissions. There are no silver bullets – we must simultaneously act on a number of fronts in each sector. The threat of lock-in and our geographic/emerging cities focus narrowed the field of options to the most urgent interventions (Figure 2):
      Power: Emissions from existing coal plants should be reduced and new investments in coal-fired generating stations should be discouraged by stressing efficiency and renewable alternatives, such as wind and solar. But when coal plants are unavoidable, they must be built to capture and sequester carbon emissions.
      Industry: National and/or sector-specific carbon caps are absolutely essential for reining in top emitters, such as steel mills and cement plants. Improving the emissions profile of mid-market companies – which are collectively as dirty as top emitters – demands utility reform, adoption of international “best-practice” technology, and new standards for the motors, pumps, boilers and other “universal” equipment systems found in most every factory.
      Buildings: New buildings and appliances, properly engineered, offer three times the carbon reduction potential as retrofits. Realizing this potential will require broad adoption of national and provincial building codes and appliance standards that are adequately enforced. New, low-cost technologies now available in the U.S. and E.U. must become prevalent around the world. Utility reform will accelerate retrofits and turnover of existing buildings and appliances.
      Transportation: New efficiency and fuel standards will cause vehicles to go farther on less gas and emit less carbon. These benefits, however, will be neutralized if vehicle use continues to soar. Better mass transit and smarter urban growth are needed to ensure that tens of millions of new cars stay parked. There’s no reason why the architectural creativity on display in places like Shanghai can’t be complemented with imaginative urban planning that creates the next generation of sustainable, low-carbon mega-cities.

      Some of the stated “objectives” are plain common-sense improved efficiency and fuel standards for automobiles plus energy efficiency measures, which are being done in an ongoing manner as economics of more expensive energy indicate. Then there is some lip service to future ” imaginative urban planning that creates the next generation of sustainable, low-carbon mega-cities..

      I believe this part is “boiler plate”, designed to detract from the real objective

      IMO the real objective is to force top-down governmental pressure for ”carbon cap and trade” legislation, and/or massive subsidies for renewable alternates, such as “wind and solar” to replace coal and ”carbon capture and sequester” (CCS) schemes.

      It is not possible to find out who the specific individuals behind the ClimateWorks Foundation really are, but it is a good bet that they stand to gain from these schemes, in one way or another.

      Follow the money trail…

      Max

      • The pernicious thing that con-artists like climate communication is doing is robbing the opportunity of the victimized charitable groups that fund them so well is to do real good in the world.
        The lefties that have hijacked the boards of far too many charitable groups see that their money goes to fellow lefties, like those at PBS, NPR, greenpeace, etc. This means the money will go to very little benefit of the poor, the sick, actually cleaning up the environment, actually improving things like drinking water. Instead it gets spent on grants to yet other lefty political hack groups, lobbying for legislation, and awards to people, for instance like Hansen and his cash prize from the Heinz foundation.
        NGO’s are not our friends. They are undemocratic, highly political, elitist, seek power far beyond their numbers and are untaxed, unregulated, unaccountable.

  68. Alexander Harvey

    Pekka,

    Do you know what formal methods are being used to evaluate uncertainties at Olkiluoto Complex (ONKALO). I must imagine that the science is very well understood and the technology refined to a high degree over normal operating timescales but given the intented purpose the outcome is hopefully completely unknowable and how to reason under deep uncertainty must be a challenge.

    The ability to determine only failure but never success has some elements that are shared with the climate issue. If mitigation were apparently successful it could be very difficult to determine if it had been necessary. More importantly there may be very little ongoing feedback and almost no feel-good factor. A course of action, embarked upon at great expense that would have to be maintained beyond one generation of experts, politicians, and voters, may never be obviously justifiable providing it is sucessful. It is my prejudice that if agreeing to start mitigation were possible, maintaining it would be extremely difficult, and I do not hear much discussion on the practicalities of providing sufficient feed-back to maintain the will to continue, it may have to rely heavily on other sources of motivation. Adaptation, hopefully preemptive, may be more easily motivated and in some senses preferable if a satisfactory outcome is possible. As to whether it would be cheaper or even timely is not something I have any opinion on.

    Alex

    • Alex,

      I have no precise knowledge on that issue. People doing the safety analysis are certainly applying to some extent methodologies familiar to many of them from the safety analyses of nuclear plants, but my view is that the case of Onkalo is much simpler, because there aren’t really any processes that can be envisioned that would lead to a major catastrophe. Even the most pessimistic scenarios imaginable would lead only to a minor increase in the environmental radioactivity, and that includes also the possibility that someone will in the distant future dig a hole to the burial site. Such an activity might expose people directly involved but even that would lead only to a local damage.

      Basically by far most of the cumulative risk of nuclear energy comes during the operation, next comes the time the fuel is in temporary storage that requires active cooling (as evidenced by Fukushima). After that the risk is dramatically reduced even in cumulative consideration over very long periods. There are also risks from the mining and processing of the ore, which exceed essentially that of the spent fuel put in a permanent storage of the type of Onkalo. The long term storage is really an issue that has been overemphasized very strongly. Nuclear waste requires proper handling, and placing spent fuel and high activity waste in a carefully chosen location deep underground is justified, but when that has been done, it’s not really a problem or reasonable cause of worry. The risks of the radioactivity get reduced fast enough to cancel the apparent problems related to the very long time scales. A possibility of a little damage with low probability in very near future is a non-problem. The general fears are apparently based on not realizing (or denying the fact) that the potential damage in distant future is actually very limited even in worst case scenarios, because the materials are in a form that reduces effectively the mobility of the radioactive atoms.

      There’s one philosophical problem related to very long lived nuclear waste even in the case, when the maximal exposure to any individual at any future time is small. That’s related to the possibility that very many people over very many generations will be affected a little – perhaps enough to shorten their expected lifespan by one second. If the influence persists for millions of years and assuming that human race will also persist that long, the calculational non-discounted sum may grow large even from extremely small individual effects. Such a sum is meaningful for activities, which are expected to continue as long as that would lead ultimately to a large cumulative effects also on individual level, but otherwise one may well question the significance of the effect.

      • Alexander Harvey

        Pekka,

        Thanks that clears things up. I thought I had missed something. The nuclear and material sciences are very well known and the geology has already tested itself. The public concern is very real if unjustified. I have previously seen the feature length documentary on Onkalo which was not sufficiently informative but was well produced.

        Alex

  69. doskonaleszare

    Dear Dr. Curry,

    Since you didn’t respond to my points about the CCSM3 tuning ( http://judithcurry.com/2011/10/17/self-organizing-model-of-the-atmosphere/#comment-123937 ), I have another question regarding your paper. In section 4.1, “IPCC’s detection and attribution argument”, you write

    “The IPCC AR4 (Chapter 9) describes two types of simulation methods that have been used in detection and attribution studies. The first method is a ‘forward calculation’ that uses best estimates of external changes in the climate system (forcings) to simulate the response of the climate system using a climate model. These forward calculations are then directly compared to the observed changes in the climate system.”

    Whereas in section 4.2 “Sources of uncertainty” you claim that

    1. “The 20th century aerosol forcing used in most of the AR4 model simulations (Section 9.2.1.2) relies on inverse calculations of aerosol optical properties to match climate model simulations with observations. The only constraint on the aerosol forcing used in the AR4 attribution studies is that the derived forcing should be within the bounds of forward calculations that determine aerosol mass from chemical transport models, using satellite data as a constraint. The inverse method effectively makes aerosol forcing a tunable parameter (kludge) for the model, particularly in the presatellite era.”

    and

    2. “Given the large uncertainties in forcings and model inadequacies in dealing with these forcings, how is it that each model does a credible job of tracking the 20th century global surface temperature anomalies (AR4 Figure 9.5)? Schwartz (2004) notes that the intermodel spread in modeled temperature trend expressed as a fractional standard deviation is much less than the corresponding spread in either model sensitivity or aerosol forcing, and this comparison does not consider differences in solar and volcanic forcing. This agreement is accomplished through inverse calculations, whereby modeling groups can select the forcing data set and model parameters that produces the best agreement with observations. While some modeling groups may have conducted bona fide forward calculations without any a posteriori selection of forcing data sets and model parameters to fit the 20th century time series of global surface temperature anomalies, the available documentation on each model’s tuning procedure and rationale for selecting particular forcing data sets is not generally available.”

    In (2), you claim that “some modeling groups may have conducted bona fide forward calculations” and “the available documentation on each model’s tuning procedure and rationale for selecting particular forcing data sets is not generally available”, which suggests you really don’t know which group used forward calculations because you couldn’t find their documentation (for whatever reason).

    However, in (1) you claim “the 20th century aerosol forcing used in most of the AR4 model simulations (Section 9.2.1.2) relies on inverse calculations of aerosol optical properties to match climate model simulations with observations”.

    So again, could you please provide any evidence supporting this claim (and no, AR4 section 9.2.1.2 won’t suffice, as someone already had explained it here http://judithcurry.com/2010/10/24/overconfidence-in-ipccs-detection-and-attribution-part-iii/#comment-5700 )? Or could you at least name the models which “have conducted bona fide forward calculations”, and the ones (“most of the AR4 model simulations”) that have not?

    To help you with that task, here’s the list of models used in chapter 9 to evaluate simulations of 20th century climate change and including both anthropogenic and natural forcings:

    CCSM3
    ECHO-G
    GFDL-CM2.0
    GFDL-CM2.1
    GISS-EH
    GISS-ER
    INM-CM3.0
    MIROC3.2
    MRI-CGCM2.3.2
    PCM
    UKMO-HadCM3
    UKMO-HadGEM1
    ECHAM4-OPYC3
    GFDL-R30

    Which ones had relied on inverse calculations of aerosol optical properties, as you claimed in your paper?

  70. Climatology is a field in which the data are noisy and sparse, and trends are buried in a sea of chaotic excursions. The present is not very interesting. Only the distant past and the distant future matter. These can only be described or predicted very crudely, and in most cases, results can neither be validated nor proven wrong. The only types of personalities who can prosper in this environment are those who can tolerate great uncertainty and subjectivity.
    Weiler et al. (2011) provide a very interesting insight into the personalities of climate scientists. Personality types of interdisciplinary, Ph.D. climate change researchers were collected based on a Jungian type personality assessment. Each person is characterized by four personality traits Extraversion vs. Intraversion
    Sensing vs. Intuition
    Thinking vs.Feeling
    Judging vs. Perceiving
    Climate researchers were compared with the general public
    Extraversion/Intraversion : Climate scientists similar to general public (roughly 50% extravert and 50% intravert)
    Sensing/Intuition: Climate scientists were far more likely to use intuition (82%) over sensing (18%) than the general public that preferred sensing (73%) vs. intuition (27%)
    Thinking/Feeling: Climate scientists were somewhat more likely to use thinking (49%) over feeling (51%) than the general public that preferred feeling (60%) vs. thinking (40%)
    Judging/Perceiving: Climate scientists were far more likely to use judging (73%) over perceiving (27%) than the general public that was more even with judging (54%) vs. intuition (46%)
    One thing stands out. There is a huge statistical inversion between climate scientists vs. the public in that climate scientists greatly lean toward intuition whereas the public heavily leans toward sensing. This implies the climate scientists “focus on theories” and “follow hunches to reach conclusions” whereas the public tends to “focus on experience” and “build carefully and logically towards conclusions”. The strange thing is that one would expect that the very nature of the scientific method requires that scientists should focus on sensing, rather than intuition. In addition, there is also a much stronger tendency of climate scientists to prefer judging to perceiving, and there is a somewhat greater tendency of climate scientists to prefer thinking to feeling. Thus climate scientists tend to “prefer to make decisions quickly, come to closure and move on”. This is clearly evident in the many papers in climatology that utilize a penny’s worth of data to draw a dollar’s worth of conclusions.

    • As an ISTP, I can say that this:

      > Thus climate scientists tend to “prefer to make decisions quickly, come to closure and move on”.

      can’t follow from the fact that climate scientists are relying on Intuition, more so when 73% are Judging.

      That the scientific method relies on sensing is obvious to anyone who works mathematical fields.

      Donald Rapp’s reading of this article deserves due diligence.

      So complete citation needed.

    • Donald;
      Edit note: In this passage:

      Judging/Perceiving: Climate scientists were far more likely to use judging (73%) over perceiving (27%) than the general public that was more even with judging (54%) vs. intuition (46%)

      I believe the final “intuition” should be “perceiving”??

    • And the take-away seems to be that the climate scientists are much more inclined to follow their own intuition (beliefs) than the data (perception). Perfect “Cargo Cultists”, IOW.

      Nice to have verification of what was clear from their behavior.

  71. Do a blog post. complete the staff work