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Not Physics ― Rather, Fudge Factors

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  • #16
    Originally posted by Leonhard View Post
    Was there anything worth picking up in anything I've written in this thread so far?
    First, there are certain facts that need to be clarified.

    You mention Anthony Watts at least three times in your response, when not a word in the OP had anything whatsoever to do with Anthony Watts. Perhaps you mistook the fact that the article was copied on Watt's blog to mean that Watts wrote the OP? I clearly noted the actual author at the beginning of the OP.

    You asked if Dyson and Lindzen are climatologists, and then, apparently presuming that they are not, you present a lecture presumably besting their expertise, experience, and knowledge with your expertise, experience, and knowledge as a 27 year old student.

    Did you overlook this section of the OP?:
    Then in the late 1970s, he [Dyson -JR] got involved with early research on climate change at the Institute for Energy Analysis in Oak Ridge, Tenn.

    That research, which involved scientists from many disciplines, was based on experimentation. The scientists studied such questions as how atmospheric carbon dioxide interacts with plant life and the role of clouds in warming.

    With regard to Lindzen, the link I provided in the OP notes that he is an atmospheric physicist known for his work in the dynamics of the middle atmosphere, atmospheric tides and ozone photochemistry. He has published more than 200 scientific papers and books. From 1983 until he retired in 2013, he was Alfred P. Sloan Professor of Meteorology at the Massachusetts Institute of Technology. He was a lead author of Chapter 7, 'Physical Climate Processes and Feedbacks,' of the IPCC Third Assessment Report on climate change.

    Just to show that Dyson's point about fudge factors in not a product of what you suggest to be senility and incompetence on his part, consider the following:
    New paper explains why a new approach to climate modeling is necessary

    A new paper by an international team of climate scientists explains why conventional climate models will continue to be unable to simulate the most essential aspects of climate such as convection, clouds, gravity waves, atmospheric circulation, ocean oscillations, etc. "for the foreseeable future" and "the fact that according to the last two assessment reports of the IPCC the uncertainty in climate predictions and projections has not decreased may be a sign that we might be reaching the limit of climate predictability, which is the result of the intrinsically nonlinear character of the climate system (as first suggested by Lorenz [father of chaos theory])."

    The authors note that to properly simulate these features with the current crop of numerical climate models requires "extremely high resolutions" of 16 kilometers or less, in comparison to state-of-the-art climate models which use much lower grid resolutions of 50 to 100 to up to 10,000 kilometers in size. For example, prior work has demonstrated that proper simulation of convection requires model resolutions of 1-2 km, up to 2 orders of magnitude [100X] higher resolution than today's fastest supercomputer models are capable of attaining. The same is true for proper simulation of clouds, the Earth's sunshade.

    To try to get around this limitation, climate models consist almost entirely of "parameterizations," which is a fancy word for fudge factors. As climate scientist Dr. Roger Pielke Sr. pointed out in a recent comment, and contrary to popular belief, climate models are not based on "basic physics" and are almost entirely comprised of parameterizations/fudge factors:

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    • #17
      Thank you for the reply John, you made some points I will acknowledge and others I disagree with. Its late in the day and I need to finish some things before heading to bed so I won't reply tonight. I live in Denmark, and I'm more than six hours ahead of your clock (or nine if you live in east coast).

      The link provided in the post doesn't work, so I can't read up on that article save for the quote you gave. Would you mind fixing that?

      Edit: Nevermind, a little digging provided the original article Stochastic Climate Theory and Modelling as well as the one you linked to New paper explains why a new approach to climate modeling is necessary

      I will definitely read these tonight and then post tomorrow.
      Last edited by Leonhard; 09-12-2014, 02:32 PM.

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      • #18
        Originally posted by Leonhard View Post
        Thank you for the reply John, you made some points I will acknowledge and others I disagree with. Its late in the day and I need to finish some things before heading to bed so I won't reply tonight. I live in Denmark, and I'm more than six hours ahead of your clock (or nine if you live in east coast).

        The link provided in the post doesn't work, so I can't read up on that article save for the quote you gave. Would you mind fixing that?

        Edit: Nevermind, a little digging provided the original article Stochastic Climate Theory and Modelling as well as the one you linked to New paper explains why a new approach to climate modeling is necessary

        I will definitely read these tonight and then post tomorrow.
        Sleep well.

        Perhaps when you return you can explain this excerpt from the original article:
        Here we argue, that rather than pushing out the limit of skillful ensemble predictions by a few days, more attention should be given on the assessment of uncertainty (as already proposed, e.g., Smith149). Ideally, it should be carried out alongside the physical parameterization and dynamical core development and not added a posteriori. The uncertainty should be directly estimated from within the parameterization schemes and not tuned to yield a particular model performance, as is current practice.

        Also, lest I forget to reference it later, consider Lindzen's support for Dyson's comment about "fudge factors" here:
        Lindzen also disputes the accuracy of the computer models that climate scientists rely on to project future temperatures. He contends that they oversimplify the vast complexity of the Earth’s climate and, moreover, that it’s impossible to untangle man’s effect on the climate from natural variability. The models also rely on what Lindzen calls “fudge factors.” Take aerosols. These are tiny specks of matter, both liquid and solid (think dust), that are present throughout the atmosphere. Their effect on the climate—even whether they have an overall cooling or warming effect—is still a matter of debate. Lindzen charges that when actual temperatures fail to conform to the models’ predictions, climate scientists purposely overstate the cooling effect of aerosols to give the models the appearance of having been accurate. But no amount of fudging can obscure the most glaring failure of the models: their inability to predict the 15-year-long (and counting) pause in warming—a pause that would seem to place the burden of proof squarely on the defenders of the models.

        Just to complete what I know of Lindzen's references to "fudge factors", he mentions the subject in the video that is made accessible here.
        Last edited by John Reece; 09-13-2014, 08:54 AM.

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        • #19
          Originally posted by Leonhard View Post
          For some reason Anthony Watts and other dissenters talk about Al Gore as if he was an originator of climate science. That its all just political propaganda he drummed up during his bid for presidency. This is simple not the case. He was probably the first political candidate to popularise the fact that there's global warming. As such he made some mistakes that scientists didn't have consensus on.
          The whole subject has been mainly a political one. Real science has been put into the back of the bus.
          Micah 6:8 He has told you, O man, what is good; and what does the LORD require of you but to do justice, and to love kindness, and to walk humbly with your God?

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          • #20
            Originally posted by Leonhard View Post
            As such, I might be very convinced that the consensus on the Global Warming science is correct, however I'm also able to change my mind (ask anyone here). If you're similarly disposed, I hope we can have a discussion now and then.
            Thanks for the apology.

            I have no oar in this trip. I do not have the scientific expertise to make a judgement. What I do have is the ability to recognize the fact that scientific discussion has been shut down politically by true believers. If the science is so strong why is that the case?
            Micah 6:8 He has told you, O man, what is good; and what does the LORD require of you but to do justice, and to love kindness, and to walk humbly with your God?

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            • #21
              Sorry that it took so long for me to respond, I've been busy writing my thesis these past two weeks and visiting family.

              Originally posted by John Reece View Post
              You mention Anthony Watts at least three times in your response, when not a word in the OP had anything whatsoever to do with Anthony Watts.
              Anthony Watts is currently the ring leader of the Global Warming Dissenter movement. So when you take the quote that all scientists must be skeptics, and since you presumably respect Anthony Watts as a skeptic and as representing 'real science', I think its fair to point out that what Anthony Watts does isn't skepticism. Taking a critical stance is good, but forever holding off assent isn't.

              Perhaps you mistook the fact that the article was copied on Watt's blog to mean that Watts wrote the OP?
              Looking back I might have done that, though I don't remember it. That seems plausible given how I've written it. I admit this mistake.

              You asked if Dyson and Lindzen are climatologists, and then, apparently presuming that they are not,
              I'll stand by what I've said on Dyson. Its true that he participated in a multidisciplinary climate studies, where he could lend his insight to it. That doesn't indicate whether in fact he had anything useful to contribute with. I haven't found anything about the impact he had, or what he helped develop. All the article states is that in his opinion their work was full of 'fudge factors'. He mentions one, which isn't a fudge factor but a well modelled phenomenon.

              you present a lecture presumably besting their expertise, experience, and knowledge with your expertise, experience, and knowledge as a 27 year old student.
              Yes. I don't mind calling out an old physicist for being wrong. Roger Penrose is likely wrong about his latest model about cosmological evolution and I don't mind detailing the arguments why. Other than being famous for his work on quantum field theory, and various other related aspects, and being a physicist rock star, Freeman Dyson's own personal opinion isn't much to hang a hat on.

              Its up to him to argue why he should be taken seriously here, and he's given nothing but arm waving. I'm open to know more from him, but I haven't found anything else than a few snippets about his personal opinions.

              With regard to Lindzen, the link I provided in the OP notes that he is an atmospheric physicist known for his work in the dynamics of the middle atmosphere,
              Granted.

              Just to show that Dyson's point about fudge factors in not a product of what you suggest to be senility and incompetence on his part, consider the following:
              [indent]New paper explains why a new approach to climate modeling is necessary
              This article has nothing to do with the article you linked to originally, and I criticised you and global warming dissenters for using Freeman Dyson as an authority in this field. I pointed out that it talked of 'fudge factors', but only mentioned the positive feedback part of water vapour response to CO2 (there's also negative ones), which is fairly well understood now.

              I've read through the article. The author shows very little understanding of what he's just written, especially given the link he gives at the end. However its not directly relevant to this argument, because other than the author making the mistake of thinking that parameterisation is the same as 'fudge factors' which would imply that basic electronic circuit simulators are nothing but fudge factors in his opinion. Its a very jarring mistake.

              I can see why someone who has never studied science would make that mistake because he's not really understanding what he's reading he's just searching for keywords that he think he understands.

              The article itself was about how hard it is to get to the next paradigm of climate and weather prediction.

              Imagine breaking an area of the sky down into a number of cubes. There's air in each of those cubes. Now if you want to simulate how that large body of air would move you'd need to describe how the air inside each box moves. We could be simple and say that all the air inside each box has the same direction, speed, pressure and temperature. That would take five numbers for each box to specify, and we could pluck that into a computer model that would show what should happen to the numbers in each of those boxes depending on what's in their neighbours.

              That's the foundation for finite-element analysis. Make the cubes small enough and you can calculate as precisely as you want how the air moves. There are limits to the predictive power of this, as the tiniest difference between reality and the model will overtime skew the result quickly until there's no overlap. That's why the weather report is only good a few days ahead.

              If we make the cubes ten or a hundred times smaller, we might be able to do two more days.

              However maybe we can get away with merely using more numbers to describe how the air moves inside each box? That's what they suggest. With a number indicating whether it has angular momentum, and how much moisture it contains, as well as various other modes of movement.

              There's nothing fudgy about this, its just replacing a hundred smaller cubes by one larger cube that has numbers that model the relevant behaviours of smaller cubes.

              Sometimes that's more efficient. However it has nothing to do with inserting constants that are fine-tuned to give the values you want, or whatever is being implied here.

              The article closes off by saying that in these cases simpler 'stochastic' models are to be prefered. The author then links to a 'stochastic' model of the climate, which he says is the kind of example they're implying. Except it isn't stochastic, and it has nothing to do with what they're saying. It was a home-brew model using a couple do dozen sine and cosine functions fitted to the climate data.

              That might sound technical and impressive, but its not. If you take a number of data points, and enough mathematical functions with constants (real fudge factors) to them and then you ask a computer to find the values for the constants that make the resulting curve most closely match the data... you can fit an elephant if you want.

              So the author spends all his time railing against fudge factors which he thinks is the same thing as parametrization, but then he links approvingly to a model which is harmonic (think lots of sine and cosine functions) and not stochastic (probabilistic models) [meaning he can't even tell the difference between those names].

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