Lucia has a bad week on partial derivatives

We welcome collaboration, but empty, uninformed ill-will doesn’t help the unresourced skeptics to beat the billion dollar green machine.  It’s time for Lucia to admit she got it wrong. Lucia’s second post failed to clarify anything. She didn’t acknowledge that she had not found a single real mistake David’s work, nor did she apologize for getting so much wrong. Having decided everything David was doing was “crud” after reading two paragraphs, she now has the onerous and pointless task of trying to defend a hasty uninformed position.

Lucia didn’t have to dig the hole deeper but she tried. To turn her mistaken accusations into something useful she transparently shifts the goals and won’t join the dots. Evans was critiquing Held, Soden, and Pierrehumbert. He described how they relied on partial derivatives of dependent variables, impossibly holding everything else constant in climate and thereby incurring unknown errors. Lucia now says “but they could’ve done it a different way without them” and perhaps hopes no one notices the unspoken admission that David Evans was right.

The bizarre thing is that you don’t need a maths degree to know her method is silly on its face. In the real world there is no way to hold temperature, clouds, humidity or anything constant while changing the surface temperature —  and mathematical trickery won’t make it so. (Lucia packs the changing variables under a term she calls Rp  — which is a bit like hiding income in an offshore tax avoidance scheme.)  The bane of basic climate analysis that inevitably it has to use partial derivatives while unrealistically holding all else constant — the issue is ignoring the risk and uncertainty that brings.

Notably, Lucia didn’t link to our reply to her first post (despite the post being a request for a reply from David). Nor did she email us either time she published (despite having our emails). Does she want the truth, or just to indulge in point scoring snark? If she’s hoping for an easy target, she’s picked the wrong people.  – Jo

Lucia Goes Awry Again

by Dr David Evans, 20 October 2015David Evans’ Basic Climate Models Home, Nomenclature

David’s post 3: New Science 3: The Conventional Basic Climate Model — In Full

David’s post 4: New Science 4: Error 1: Partial Derivatives

Lucia’s first post on our posts, at the Blackboard: Questions to David Evans: What do you mean about partial derivatives?

Our response to Lucia’s first post: Lucia has a bad day with partial derivatives

Lucia’s second post, at the Blackboard: Held & Soden without “hypothetical partials”

Our response to Lucia’s second post: Lucia has a bad week on partial derivatives  <—- This post


As with Lucia’s first post, having read carefully through her second post and its comments, I’m still waiting for Lucia to find any mistakes in my posts or even made any informed criticism of them.

Lucia’s first post alleged I made had mistakes with differentials in post 3 of the series of posts about basic climate models. We showed her in more detail how to do them in our reply, applying an online class note from MIT that I had referenced in the first post. Lucia’s second post has no mention at all about any mistakes with differentials, which I’ll take as implicit acknowledgement that I was right — as were Held and Soden [1], and Pierrehumbert [2], whose model development I was copying. No retraction or apology from Lucia though. No one reading Lucia’s two posts would know that I was correct about differentials all along and Lucia was wrong; they’d get quite the opposite impression.

Lucia moves on to the issue of “strictly hypothetical” partial derivatives

In her second post, Lucia moves on to attacking my claim in post 4 that the partial derivatives in the conventional basic climate model, such as the Planck feedback (the reciprocal of the Planck sensitivity, λ0), are “strictly hypothetical”, and she claims that the basic model “can be developed without resorting to these “strictly hypothetical” partials”. As with her first post, Lucia was quite disparaging of me but did not bother to email us  — we weren’t so discourteous (we email Lucia immediately we post about her).

As anticipated (see Comment 37.1.1), Lucia makes her own derivation of the basic model, aiming to avoid partial derivatives where “everything is held constant”. She thinks she succeeds, but she fails. An alternative approach that got around the obvious problem with the Planck feedback (that it impossibly relies on holding all climate variables constant except OLR and surface temperature*) would clearly be an improvement, but it would almost certainly have been discovered decades ago in a problem space as small and as intensively researched as this.

We’ll skip over most of the detail of Lucia’s more complicated approach, and just focus on the crucial piece of her development. Consider the OLR function, R. Lucia does not want to use the arguments used in post 4 for G (or downward flux, ASR – OLR):

where the surface temperature is TS, there are n driver variables V1,…,Vn, and there are m feedback variables, U1,…,Um. (I’ll continue to use the notation in posts 2 to 4, rather than Lucia’s more limited and cumbersome notation.) Because the feedbacks are only functions of the temperature TS — that is, schematically Ui =Ui(TS) — Lucia prefers to write the OLR as

and let R depend on feedbacks via TS . Fair enough.

But Lucia wants to avoid using the partial derivative ∂R/∂TS where all the drivers and feedbacks are held constant — this is the “Planck feedback” (which isn’t really a “feedback” as the term is used elsewhere in this series — see post 2 and post 3 where it is discussed and defined). This is important so I’ll stress it: in the standard development in post 3, ∂R/∂TS means the derivative of R with respect to TS when all the drivers and feedbacks are held constant — and since (nearly?) every climate variable depends on feedback, basically this means holding “everything else constant” except the OLR R and temperature TS.

Can Lucia develop the basic model without “holding everything else constant” at some point?

Lucia splits R into two parts, one where drivers and feedbacks are held constant and one where they can vary, by setting

where she defines Rp (which she also writes as “Rpe“) as the OLR that “would arise on an earth whose temperature is TS” and the values of the feedbacks are the same as the feedbacks “of the current earth”. Also, Rp  “does not vary with” the drivers. That is, Rp is OLR as a function of temperature only, and which is independent of the drivers and feedbacks — so Rp is the part of the OLR where the drivers and feedbacks are held constant. The other bit, R-tilda (the R with the squiggly line on top in Eq. (3), which cannot be typed in this text), is just the remainder of the OLR, namely R less Rp — it is the part of OLR that depends on the drivers and feedbacks. Fair enough.

Lucia then develops the basic model, successfully — which is no great achievement because she is basically copying the standard approach in Held and Soden but with her different notation.

Lucia then goes on to claim, in several variations, that in her formulation of the basic model “partial differential are not taken holding “everything about the climate” constant”. Not so. Lucia’s equations (7) and (9) both contain dRp/dTS, and her result for the ECS in her Eq. (8) thus also contains it. Because she defined Rp  as the part of the OLR that holds drivers and feedbacks constant,

Yep, she has the conventional Planck feedback in her formulation too — the derivative of OLR with respect to temperature, holding all drivers and feedbacks constant.

Lucia  just reinvented the wheel with different notation

Merely due to her definition of  Rp , she can write the Planck feedback with straight derivative symbols instead of partial derivative symbols. This is mere notational trickery and legerdemain; Lucia is fooling herself and her readers with her multiple claims to the effect that her formulation does not contain partial derivatives that hold everything constant. “Her Planck feedback” is the just same as the conventional Planck feedback — dRp/dTS holds feedbacks constant, and since (nearly?) every climate variable is affected by feedbacks to surface warming, Lucia’s Planck feedback holds “everything about the climate” constant” too.

For those interested in more details, here is my analysis of her post.


UPDATE, 20 Oct 2015: Lucia has added an update to her post, a few hours after this post went live. She says

My formulation does not hold “everything about the climate” constant while taking a differential. It either holds “T” constant or “CO2” constant. Nothing else.

Early in her post Lucia defined Rp(e) with

where Rpe(T) is defined as the outgoing radiation that would arise on an earth whose temperature is T and has the ice, cloud ,water vapor and CO2 of the current earth; this does not vary with log2(CO2).

Is not that holding  ice, cloud, and water vapor constant?  Does that not imply that Rp holds constant both the feedbacks  (ice, cloud, and water vapor are the feedbacks considered in the Held and Soden treatment she is following) and the drivers (CO2 is the only driver in her context)?And does not holding feedbacks and drivers constant hold (pretty much) everything about the climate constant — except for what is involved in the differential ratio, of course?

Holding T constant in Lucia’s formulation holds the feedbacks and thus “everything in climate” constant. And yes, Lucia’s Planck feedback is the same number as the conventional one that explicitly holds “everything about climate constant”.

In a new development, Lucia did at least email us when she added the update: her entire email reads

You are so confused.

Well, at least she emailed us.


*The Planck conditions for evaluating the Planck feedback or sensitivity conventionally are that all else besides tropospheric temperatures and OLR are held constant — so there are no feedbacks, all tropospheric temperatures (including the surface temperature) change in unison, and stratospheric temperatures are unchanged (Soden & Held, 2006, pp. 3355-56). There are some arbitrary choices to be made, such as whether it is the specific or the relative humidities that remain unchanged as the troposphere warms, or what happens at the tropopause.



[1^] Held, I. M., & Soden, B. J. (2000). Water Vapor Feedback and Global Warming. Annu. Rev. Energy. Environ., 25:441–75. This seems to be legit: See section 3.4.2, pages 135 – 138 of this pdf.

[2^] Pierrehumbert, R. T. (2010). Principles of Planetary Climate. Cambridge: Cambridge University Press.

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122 comments to Lucia has a bad week on partial derivatives

  • #
    Kevin Lohse

    It’s a great shame that two such well-respected sources of real science are reduced to megaphone argument. And please, no, “she started it”. When scientific egos clash, the only victim is the scientific truth. How about BOTH sides taking a deep breath and starting over?


    • #

      Yes, agreed

      As I commented a week or two ago, it seems to be some version of inverted snobbery, related to web traffic numbers, or platform credibility/authority, or some such. Evans has the most convincing argument but ego intervenes, I’m afraid …

      I think this because neither “side” will actually address the issue on the other’s website, so we “customers in the middle” are treated to shadow boxing from all angles

      The only time in the last 10 years I’ve ever seen a real scientific dustup occur with everyone commenting on the same website happened with the Beanstock et al paper on mathematically correct use of statistical models. The debate occurred on (I think) Bart Verheggen’s website and raged on and off for several weeks. A few protagonists left in a huff but most stayed the course. The result was actually educative – the model physicists, while grudgingly admitting that Beanstock’s criticism of their usage was mathematically correct, maintained that the statistical theory was “unphysical” (ie. it gave physically impossible results). The statiticians insisted that the stats models could not give a reliable answer with the available data (Bayesian priors, you know) so it was pointless trying to scare the bejesus out of the populace with unreliable conclusions. That was a REAL outcome, in my view – the uncertainty within science as applied to climate became starkly clear


      • #

        Kevin. No hyperventilating going on here. No megaphone either.

        Just point us to one mathematical thing that Lucia got right about David’s post #4.


        • #

          Ian, With respect, David is addressing her points exactly. I don’t see how replying on her site helps? It’s difficult to post an appropriately long reply with equations over there, and in any case, by the time we know she’s posted there are already a lot of (mostly pointless) comments at the blackboard.

          We’ve done the right, civil and well mannered thing in every way.

          We wrote 8 – 10 polite emails to her the weekend before last, before we published anything at all to give her space to step back quietly and save face. But she insisted she would not “waste her time” solving this by emails. She wanted it all public. So “public” it is.

          Unlike us, she doesn’t link back to our replies in her posts, or buries the link in her posts to our post replies. (Try to find her link to our reply last week in the post. Yet it is supposedly the post she is responding too?). Does she want her readers to read our replies? It doesn’t appear so. Her commenters often don’t have much information.

          It makes sense to post here where all the information is and where more commenters have actually read our posts.

          Lucia is and has always been welcome to comment here.

          PS: I’ve edited the first line. It was a bit blunt.


          • #

            Her commenters often don’t have much information

            I’m not suggesting anyone has been explicitly rude, and I will agree that Evans has shadow-boxed a lot less than LB

            But the highlighted quote above still stands as the real issue – and this happened on the Bishop Hill site as well, even though Montford specifically pointed to your website … his critical audience simply refused to read the posts here, just waffling on along various irrelevant paths

            I can only guess as to why people comment critically without first reading what it is they are critising … but it happens constantly and it’s certainly not healthy for open science. Smacks of snobbish tribalism, or vanity, or who knows ?

            I’m sure you read my comment where I opined that Evans had the most convincing argument. We are told he has submitted this as two separate papers for peer review and publication. He could not know who the reviewers are, but which Journal, please ? (in the expectation that publication will eventually occur)


            • #

              Ian, I don’t see this as an issue of us doing “less shadow boxing”, but as a case of black and white maths (David is right), and good manners (eg: do your research before posting, and ask privately in email).

              I spent hours trying to make the first response to Lucia last week as diplomatic as possible. Less so this time. Those were hours I could have spent with my family.

              I believe skeptic-v-skeptic battles are mostly a waste of time, but some people seem to think Lucia may have made a useful point, so we have to correct that.

              PS: If we were to name the journal, those editors would come under a lot more pressure don’t you think?


          • #


            At one point I’d been posting about how I thought the effect of “volatility” was being left out as things like high altitude stations were removed from the data set ( I think this shows up in the ever lower range of the MIN temps now vs the past). I’d had a posting on WUWT as well.

            I’ve carefully not mentioned the following to anyone out of a sense of proper polite behaviour:

            I got an email from Lucia of The Blackboard asking me would I be interested in making my argument there. Sort of flattering, I guess.

            I responded that no, I was not interested, I had my own blog.

            Then I may have gone a bit too far. I characterized our two styles as being different using a metaphor that is meaningful to me, as I learned it growing up in a restaurant. Some folks like eggs ‘sunny side up’ and a bit runny. Some like to dump hot sauce on that. No matter how the customer orders their eggs, that’s a good way and your opinion does not matter. These are folks who seek stimulation. Other folks like eggs cooked through, and barely a touch of salt if anything. These are folks who have way too much stimulation already, thanks, and just want a quite tasty meal. That is all truth. And BOTH are fine ways to order eggs. The customer gets what they want. Then the “to far” (maybe) was saying roughly “Your site is more like runny eggs and Tabasco and I’m more like eggs over easy”.

            To my mind, a straight forward way to say I didn’t want to be in the “fray” that often happens there, and like working at my own pace. And that, in the stated context of “both are what the customer orders and are good”, not pejorative.

            The next day I found out that she had posted that I was “no longer interesting” and ought to be ignored.

            IMHO her desire is not to find answers so much as to “add spice” (and drive traffic to her site). There are repeated clear cases of “pot stirring” and trying to arrange for two folks to “go at it” in her space. That’s the M.O.

            Well this particular Road Warrior is not interested in being in her Thunderdome while Auntie Lucia arranges the audience.

            For anyone wondering: No, I’m not pot stirring myself, nor do I give a hoot about Lucia or The Blackboard. My only desire here is to pass on my POV and understanding to Jo and David in the hope that it is more useful, rather than being an “empty distractor”. Yes, I could have done it in email, but that requires booting a separate machine ( I practice domain isolation for security reasons and do internet browsing from particular disposable machines – I am *Nix security geek and we do that kind of thing). Besides, it fits this posting topic and might help others as well. I hold no ill will toward Lucia. She has found a successful niche and enjoys “the spice”. More the merrier. Just not my style. Some folks DO like “runny eggs and Tabasco” and will be happy there. Others not so much…

            FWIW, you see a lot of those “Thunderdome pot stirrers” on the internet. It is a common strategy to drive up traffic. Not so useful for finding answers in a police cooperative setting. Doesn’t make it bad, just a different market with a different “product” on offer. Me? I’m sticking with the Library with Coffee Shop style. It suits me… And, unlike Trump, I’m not a “counter puncher”. I’m from the Aikido POV. Step off the line of attack. Let your opponent’s power sweep past you, taking them with it. Let their own actions fight with them. Do not be in the fight, let them fight only with themselves… Lucia can fight with herself over her words. In the end, facts are very stubborn things and “truth will out”.

            Speaking of Coffee Shop… I think it’s time for tea 😉


        • #
          Roy Hogue


          I’m tempted to make a play on the name Confucius and come up with a joke about, “Confusion say this,” or “Confusion say that.” But I suspect the confusion is too obvious to require stating. The ego problem is too.

          So what can one do except expose the problem? And you and David have been doing admirably for a long time.

          What more can be said?


          • #
            Roy Hogue

            Maybe I shouldn’t have said “ego”. But it does seem to be part of what’s in play when Lucia goes on and on, completely missing what she doesn’t understand.


      • #

        “As I commented a week or two ago, it seems to be some version of inverted snobbery, related to web traffic numbers, or platform credibility/authority, or some such. Evans has the most convincing argument but ego intervenes, I’m afraid …”

        That is nonsense. This is reality:

        “Lucia’s first post alleged I made had mistakes with differentials in post 3 of the series of posts about basic climate models. We showed her in more detail how to do them in our reply, applying an online class note from MIT that I had referenced in the first post. Lucia’s second post has no mention at all about any mistakes with differentials, which I’ll take as implicit acknowledgement that I was right — as were Held and Soden [1], and Pierrehumbert [2], whose model development I was copying. No retraction or apology from Lucia though.”

        And, of course, Evans is directly addressing other on-point topics.


    • #

      The reality is that when people believe that their product is the best, then they will find any insignificant, irrelevant, personal preference reason to attempt to dismiss the competing product. In this case the competing products are believers and sceptics.


      • #

        I should have clarified that it’s those with the most to lose that argue the hardest about insignificant, irrelevant and personal preferences regarding their product.


    • #

      All very interesting in an academic sense, but the real problem is that the underlying radiative physics in the climate models is totally wrong.

      It’s trivial to show that to claim surface exitance is a real instead of a potential EM energy flux, and therefore atmospheric GHGs thermalise the difference between surface exitance and OLR, creates >53% extra energy input than reality. This was known to GISS in 1976 when modelled atmospheric temperature gradient was far too high. So they invented ‘negative convection’* that maintains lapse rate. There is no such physics. They also created imaginary ‘positive feedback’ by using as a hind-casting parameter about 1/3rd more low level cloud albedo than reality. So, Hansen’s claims to US Congress in 1988 were from incorrect modelling.

      This incorrect physics was formalised by Goody and Yung in 1989, the latter being a co-author of the 1976 GISS work. However, for the surface to emit real IR energy at its ‘black body’ rate, the atmosphere would have to be at absolute zero and for the atmosphere to emit real IR energy at its Emissivity, would require the surface to be at absolute zero; ludicrous. These facts show that the heat transfer physics in the models are complete and utter bunkum and incorrect estimates of various divergences that Archibald has noted are merely a veneer of science to cover scientific failure. At some time, and I’m trying to work when, the UKMO replaced ‘negative convection’ by the equally false but more plausible Kirchhoff’s Law of Radiation approach presently used. The rest of the modelling is OK.

      Bottom line: no amount of introspective mathematical analysis of the models will correct these faults. The real atmospheric control system is based on zero net mean surface IR emission in all self-absorbed GHG IR bands; the water cycle ensures net zero warming by any well-mixed minor GHG. This PID, negative feedback control is very stable and there is substantial experimental proof of how it works, again totally missed by the Climate Alchemists.

      *Wang et al 1976.


      • #

        “All very interesting in an academic sense, but the real problem is that the underlying radiative physics in the climate models is totally wrong.”

        Good God Andrew,
        Do you wish to die, quickly, before taking out many of them?

        Fortunately you have no name or location. Please keep doing that.

        Your October 20, 2015 at 6:12 pm #1.3 writings are both precise and correct. Now what?
        All the best! -will-


        • #

          I’m keeping the best bit secret; the beautifully simple way the atmosphere self-controls so that none of the spurious maths, the carapace of complexity used to hide underlying legerdemain, which Evans is correctly criticising, is in fact needed!

          In time it will be revealed.


      • #

        I’m not saying I understood what you said; but I do agree with it.

        “the underlying radiative physics in the climate models is totally wrong”.

        David is finding incremental faults in the “Models” but it probably wouldn’t work in the media to take an axe

        to the tree of climate catastrophism and fell it at one swoop.



        • #


          I am still waiting for someone to plot the Temperature Effect of HUMAN ORIGIN CO2 against the relevant temperature reading AFTER having removed all other major effects.

          Probably going to FLATLINE.?

          Even the effect of TOTAL CO2 is swamped by that of Water and then the other factors !!!!!



          • #

            I guess what I am saying is that creating a model to specifically show the influence of Human Origin CO2 variations

            against any Atmospheric Temperature Change specific to that factor is scientifically pointless.

            On the other hand, as the IPCCCCC etc have found, there is great value in creating a computer simulation

            which purports to be a Model and claims to show how variations in CO2 (whatever that means) can change the weather.

            Why don’t we just call a spade a spade.



      • #

        The real atmospheric control system is based on zero net mean surface IR emission in all self-absorbed GHG IR bands; the water cycle ensures net zero warming by any well-mixed minor GHG. This PID, negative feedback control is very stable and there is substantial experimental proof of how it works, again totally missed by the Climate Alchemists.



    • #

      I am not sure Lucia et al’s rejection is a bad thing. Isn’t this exactly what (we) empirical sceptics have always said is a good thing: clash of ideas, robust testing and cut and thrust of debate? Isn’t Lucia’s critique (however ill-founded) an opportunity to rethink one’s position, to reconsider it, perhaps, even if only in the way one has mentally organized the building blocks, strengthening one’s position? Maybe Lucia’s and Nick Stokes dissonant (and in Stokes’ case, sneering) voices are a very good thing indeed. People are engaging with Dr Evan’s insights. They may hate the new idea on the block, but their discomfiture shows that it has arrived.


    • #

      sorry, but from Lucia this is the next tile in a pattern of bad behaviour.

      My experience of this was when I was doing some of my first climate related empirical experiments in 2010. This was looking at the Makarieva et al 2010 discussion paper that postulated that some cloud formation could cause horizontal winds. I did some simple experiments to determine if radiative cooling or edge turbulent mixing could offset the increased buoyancy of an airmass during the release of latent heat during cloud formation. Makarieva et al empirically checked out OK. The physics they were proposing were empirically replicable.

      This lead to some controversy as Willis, gatekeeper of Lukewarm at WUWT, had already condemned the paper in his acrimonious style. Lucia tried to initiate discussion on such experiments at the Blackboard, but misinterpreting the clear intent of the experiments and not having sufficient skill at FEA and CFD, Lucia led readers into an intellectual dead end of linear calculation (Hello? Hello David? Oh you-hoo! Oh you-hoodles?!). When this was pointed out, instead of admitting fault, Lucia doubled down and produced more threads to obscure initial mistakes.

      As I said, a pattern of behaviour.


  • #

    I cannot even pretend to follow the math, but I found the following a rather interesting statement:

    It is certainly true that in the real world one might have difficulty varying CO2 while holding solar insolation, volcanic aerosols, and other factors whose magnitude is almost certainly independent of temperature constant; after all, we can’t really control the sun or volcanoes. But I don’t see how that’s a large problem with respect to estimating climate sensitivity using models.

    It seems to me she is claiming that models CANNOT model ‘real world’ because in real world we cannot hold various factors at constant, but that this will not prevent models from modelling that same real world scenario.

    Am I confused or is she? 😀


    • #

      “It seems to me she is claiming that models CANNOT model ‘real world’ because in real world we cannot hold various factors at constant, but that this will not prevent models from modelling that same real world scenario.”

      Models can only help to learn with fingers crossed. Airfoil computations are checked in the wind tunnel, for accuracy. But on that flight the test pilot has all fingers and toeses devoutly crossed! The telemetry will tell all about that AW SHIT ! 😉
      Where has your CCC verified anything?

      “Am I confused or is she? 😀 -”
      How about both?+


      • #
        Peter C

        We are still waiting for that part Will.

        You are impatient.


        • #

          Peter C October 20, 2015 at 6:59 pm

          “We are still waiting for that part Will.
          You are impatient.”

          I are impatient and incontinent. You aint seen nothing yet, nurse. 😉


      • #

        Will, you mention aerofoil computations -here is a link to computational mathematics based on actual aerofoil measurements that has disproved Prandtl’s theory of fluid mechanics

        There is hope that David Evans can knock out the CAGW theories.

        There is also hope that Stephen Crothers can get new thinking on relativity and knock out the mathematical nonsense of “black holes” and “big bang” see here
        EU 2015 (Phoenix, Arizona): Stephen J. Crothers
        General Relativity – A Case Study in Numerology


        • #

          Should have added that Stephen Crothers is an Australian who understands mathematics and partial derivatives very well. I hope David has time to view the video with its mathematical examples.
          This site has three of Crothers short papers 9,12 & 15 -the latter about Nobel prize winner Brian Schmidt who has fallen in with the climate alarmists and has been feted by “our” ABC


          • #
            Peter C

            Thanks cementafriend,

            Stephen Crothers has very interesting views. The Big Bang was supposed to be a joke, made by Fred Hoyle to show how disconnected theoretical astronomy had become from observation. It got taken up and made into scientific orthodoxy.

            Brian Schmidt believes in Big Bang and Climate Change. Since he seems to know very little about Climate Change it is possible to doubt his understanding of the Big Bang also, or maybe the other way ropund.


      • #

        you bring up an interesting point about airfoils. The Wright Brothers built their own wind tunnel, and in working with it, disproved all previously accepted mathematics concerning lift/drag ratios of airfoil sections.

        The lesson is this – maths can model both the physically possible and the physically impossible. Empirical experiment can only model the physically possible.


        • #
          Peter C

          Possibly Konrad,

          The Wright Brother s made a lot of mistakes that they could have avoided. I am not sure about the validity of their wind tunnel experiments.

          However I am in full agreement with your conclusion; “Empirical experiment can only model the physically possible”


    • #

      Not just the effects of the sun and volcanoes but the close coupled effects of CO2 and H2O on heat loss.


  • #

    Oh… and also, is it rather careless to claim that

    …solar insolation, volcanic aerosols, and other factors whose magnitude is almost certainly independent of temperature …

    as a basic?

    It seems to me we already know for a fact that solar and volcanoes DO affect temperatures but she seems to be trying to use it the other way around. i.e. trying to make her case by saying temperature doesn’t affect insolation and volcanoes as if it actually is a meaningful statement.


    • #

      Saying “the magnitude of solar insolation, volcanic aerosols, and other factors is almost certainly independent of temperature” is not the same as saying “temperature is independent of solar insolation, volcanic aerosols, and other factors.”

      If you think this is not true, then please postulate a mechanism by which a typical diurnal change in temperature can change the amount of insolation or volcanic aerosols by a factor of, say, four. Or even two.


      • #

        As purely hypotheticals:

        Daily heat causes a lot of vaporization that rises to make high clouds, blocking solar insolation by reflecting more to space. Cold days not so much.

        Volcanic Aerosol encounters rain and is washed out, or not, depending on the temperature making rain clouds, or not. (See tropical rain bands vs tropical volcanoes and much less temperate desert areas vs, say, volcanoes in California and Nevada…)

        So no, the temperature on Earth does not modulate the sun, nor the volcanoes, but it can modulate the flux of “stuff” from them in the weather / climate system.


  • #

    Honest scientific inquiry & understanding are about to become & whole lot more important , if not abundant , as Canada dissappears as the West’s last political counterbalance to the climate madness


    • #
      Peter C

      Sad to see that.


    • #

      Indeed incredibly sad and tragic, if eminently predictable, where yet again the Canadians have been seduced by a Trudeau.

      Just like the U.S. who can’t seem to elect, with rare exceptions, a President whose name isn’t either Clinton or Bush, like moths to the flame the sheeple gravitate to those who would sell them into slavery at the drop of a hat, the mouthpieces of the Hegelian dialectic that forms what amounts to the facsimile of democracy in the West at the moment, which our feudal overlords serve up with glee for our mass consumption.

      It is really sad that people are so clueless that they can be led with such ease by the nose to their own detriment. The human race is IMHO, on the downward spiral to oblivion, with Paris in December the marker buoy to the windward leg of the yacht race straight to hell.

      I once held such high hopes for the future of our species, a future where all those who, by accident of birth and fate, had been unable to express their respective skills and abilities to the fullest were being freed sequentially by the relentless march of technological advancement to contribute more meaningfully to the grand pool of human knowledge, freed from the shackles of poverty and ignorance, released from the chains of superstition and belief into a saner, more rational and egalitarian world where truth was paramount, and ever-present self interest and greed were negated somewhat by the forces of innovation, inspired problem solving, altruism and shared goals in improving the lives of our peers and the desire to peaceful coexistence with others.

      Instead, we have a world riven by sectarian violence, engaged serially in state sanctioned murder, and failing conspicuously and spectacularly to cope with a rising tide of extremism, terrorism, and a recrudescence of ethnoreligious genocide, while threatened by religious fundamentalism that belongs more appropriately in the medieval rather than the modern era. Coupled with this is the complete corruption of our institutions, the loss of adherence to principle and the rule of law, a blurring of the edges in the separation of powers and the divide between Church and State, a general apathy toward the acquisition of knowledge or engaging with others mindfully, an intolerance for novel or non- conformist ideas and a rigidity in adhering to established assumed “knowledge” at the expense of broadening our understanding through challenging the prevailing wisdom to gain new knowledge to shift the paradigm to newer expanses of human ingenuity.

      Led as we are by corrupt and amoral puppets who have sold their souls in betrayal of those they are meant to serve, we are being herded off the economic precipice to a place where suffering and privation unheard of since the 1600s will become the new normal.


      • #

        I have never been a heavy drinker Winston, but you have just laid out all the reasons

        as to why over the last six months I have been drinking daily.

        Australia I Understand too well and that is why I drink;

        the way forward now is driven by media induced perceptions of reality; which aren’t too real at all.

        A country can’t move forward when we have greed based government at all levels.

        Maybe it’s better elsewhere?

        Up until recently I had high hopes that Vietnam would not mess its future up with corrupt practices as it seemed to want to do for the first 20 years after “Liberation”.

        From 1995 there appeared a new rationality in government there, which was encouraging so that an industrial park on the outskirts of a coastal city in VN was almost half full of bright new enterprises about 7 years ago.

        On a recent visit three quarters of them had shut down and what is left is teetering.

        The reasons may partly lie in the changed world market, especially the EEU, but also likely is the black hand of greed becoming stronger to the point that it strangles the golden goose.

        Not safe or sane anywhere.



        • #

          And the first order of Canadian Liberal business will be to announce that the Conservatives mismanaged the books. That announcement should appear in the next month or so.

          Then Trudeau will travel to the Paris Climate Summit to receive some obscure green award. There he will announce his profound belief in the evils of carbon, and sign whatever treaty the UN socialists put in front of his empty head.

          Then within a year, a national carbon tax law will be rammed down Canadas throat. A tax to fix the weather.

          Welcome to the Liberal world, Canada. Thanks for all your help.


    • #

      Fantastic that Harper has been booted. He was typical of modern conservatives – a corrupt, crony-capitalistic environmental vandal who relied on vapid slogans and appeals to fear and economic illiteracy to remain in office. Good riddance to another ideological dinosaur – perhaps he and Abbott can play in the sandpit together.


      • #

        Liberals in Canada invented crony capitalism. Before the election rules were changed by Chretien to spite Martin, Liberals always were #1 in corporate donations. But don’t let the facts get in your way.


        • #

          Ah, good to hear you equate corporate political donations with crony capitalism, as that is exactly what it is. Of course many of the self-styled ‘libertarians’ on this site would disagree and label such de-facto political bribery ‘freedom of speech’. This sounds like a debate the right-wing milieu should probably have out, perhaps after resolving which of the 20+, often conflicting, lines of AGW denialism they should stick to. Oh wait, I forget – such trivialities don’t matter when you should be as a team fighting the Left devils.


          • #

            ”Oh wait, I forget – such trivialities don’t matter when you should be as a team fighting the Left devils.”

            You didn’t forget, you never knew. It’s principle before side and science before politics. That’s why a Turnbull led coalition will lose the next election. What coalition voter is going to donate funds, door-knock, letter-drop or man the polling stations for the Waffling Wamulonian?


      • #


        So, Al Gore isn’t a crony capitalist? Goldman Sachs, controller of both Gore and Malcolm Turnbull, isn’t the ultimate poster child corporation that embodies and has perfected the concept?

        Wake up, doofus, you are on the WRONG side of that argument, along with all the corporate raiders, investment bank vultures and corporate fascists who are hoping to socialise their debt to the humble taxpayer, while corporatising as much unearned wealth as they can into the hands of the 0.00001%. They rely completely on the gullibility of people like you, who naively think they are on the side of those “saving the world” from the vagaries and the vicissitudes of weather. Sheesh.

        How many cyclones are you going to stop by taxing my @ss, hey Steph? Five? Seven?

        Can I choose? Perhaps I could stop 3 thunderstorms, two typhoons, one crippling drought, and a partridge in a pear tree? I mean really, what kind of nitwit thinks that is really the aim of such corporatist people, rather than merely facilitated theft for their own enrichment.

        Meanwhile, in your alternate version of reality, social democrat, volunteer firefighter and surf lifesaver Abbott is some kind of corporate stooge, but investment banker, globalist crony Malcolm Turnbull is a humanitarian and planetary saviour. Wow. Perceptive, aren’t you.

        [Let’s try to keep it a little less personal and more objective. Thanks.] AZ


        • #

          Sorry to negate your whole ‘big green banker’ attack, but I’m actually more in favour of a straight CO2 tax, revenue-positive, payable directly into consolidated government revenue.


          • #

            Not to worry folks, available for a limited time only, you can get your very own bottle of patented Stephan’s Man Made Global Warming Elixir.

            Approved by 97% of scientists and guaranteed to stop floods, droughts, wildfires, storms, disease, melting glaciers, hurricanes, asthma, heat waves, and even mental anguish from that worrisome global warming.

            Blends perfectly with Kool Aid and is the official drink of the Global Warming Tax and Alarmist Society.

            Please drink irresponsibly and send your money quickly,


          • #

            Come on, Stephan.

            You need to do better than red thumbs.

            Finland introduced the world’s first carbon tax in 1990.

            Extreme weather stopped: Zero.


          • #

            Hi Stephan,

            So your policy prescription for fixing MMGW is simply a means to increase revenue for Government.

            Amazing – looks like you just had an intense moment of honesty.

            So – it really is – just about the money.


      • #

        So Harper was a “…typical of modern conservatives – a corrupt, crony-capitalistic environmental vandal…. “

        You, Stephan, of course prefer a good Socialist/Communist government?

        We all know how great those governments have proved to be.

        61,911,000 Murdered: The Soviet Gulag State
        35,236,000 Murdered: The Communist Chinese Ant Hill
        20,946,000 Murdered: The Nazi [National Socialist] Genocide State

        [Snip etc etc… This is all real but far off topic. Please take this discussion to another thread.! – Jo]


      • #

        Wow…I havent heard such perfectly formed agitprop for a long time….in the classic Soviet style….


        • #

          ”I haven’t heard such perfectly formed agitprop for a long time”

          You admit this?! This reads as a clear confession that you, comrade, have not been focused on the accurate informations provided by their ALPBC and Fauxfacts. Are you but a lick-spittle lackey of the capitalist running dogs? Such revisionist back-sliding cannot be tolerated! You will be Purged!!


  • #

    Isnt it just as well to be keeping the noise over at Lucia’s blog, while she wrestles with her own incomprehension ?

    Without all the time in the world to follow this I appreciate the succinct account we get here.


  • #

    Had a minor run-in there a while back. Lucia knows best. Haven’t looked there since.


  • #
    Peter C

    I have visited the Lucia (Blackboard) site a few years ago. I formed the view then that she was rather opinionated and did not give alternative views much, or even any consideration. I have not been back recently. I certainly don’t mind seeing a bit of roasting now. Don’t hold back.


  • #

    Dear all,

    The math is quite dense in Lucia’s answer.
    Thanks to David’s clarifications, I have been able to follow things up.

    I believe the matter is simple in fact.
    Here’s a comment I have given to Lucia because I think it may help to go past the superficial notation stuff.

    “my math doesn’t claim to hold all these constant while taking partial differences.”

    But David Evans is clear on the thing he perceives as a problem: the need to hold things constant.

    In S&H, this happens at one and only one precise point: while taking partial differences. So David Evans has naturally focused on the partial derivatives.

    But that’s how the problem manifested itself, not what the problem really is.

    Yes your explicit way do not need to hold all things constant while taking partial differences. You have very well demonstrated there is a way to not make such claims all at once.

    You just made the hypothesis at different moments. As a consequence quite a bunch of things still need to be held constant during calculus. But not all.

    The one that does not, the derivative of Rpe, has been freed because you defined it that way.

    You have hold things constant for Rpe at definition time to free yourself from doing it at calculus time.

    This subtle shift only changes how the problem is manifesting itself, not what it is.


  • #

    In your pdf, you offer this advice:
    “Nick quotes AR5 on other more complex models but fails to note that the blog series is about the conventional basic climate model. There is only one, the really basic one, in the climate textbooks, and so on. Nick, read post 1 for why this is relevant and important.”

    This is said over and over. But where is this “conventional, basic” model set out. We were told that is is a ” IPCC core basic model”. So I asked where in the IPCC one might find it. No response.

    If it is a conventional basic model, you’d expect to find a reference saying that indeed, it is such. You give just two references. One is to Soden and Held, 2000. This is actually a review of feedback. The relevant section starts:
    “The simple radiative-convective framework teaches us to think of the energy balance of the Earth as a whole as the starting point for discussions of climate sensitivity.”

    They are describing a simple framework to teach something. It’s a starting point for discussions. No claim of a basic conventional model there. So I look at your second reference there:
    “more completely on pages 163–165 of the “gold standard” of climate textbooks, Raymond Pierrehumbert’s Principles of Planetary Climate “

    It is in a section called “4.3 The Grey Gas Model”, subsection “4.3.2 Radiative properties of an all-troposphere dry atmosphere”. The author takes pains to note that he is talking about general planetary atmospheres. Is this even an Earth model? No, the first exercise on p 163 begins:
    “Exercise 4.3.1 This exercise illustrates the fact that if the Earth’s atmosphere acted like a grey gas, then a doubling of CO2 would make us toast!”

    Doesn’t sound like he’s recommending a conventional basic model for Earth climate. And that’s the thing – it’s a teaching textbook. It’s full of models that he creates to illustrate points to students. And he develops them right through the book. You can’t just pick one out from half-way through and say that is the “conventional basic model”.

    That’s my basic objection to your series. You have created that model. It would probably be useful for some purposes. But then you find fault with it – Error 1, Error 2, Error 3. And I read in the Murdoch press that the foundations of climate science are shaking. But in fact it is the model of your creation that you are finding fault with.

    So what does it have in fact to do with climate science. I read stuff like

    Part 9: headed “Error 3: All Radiation Imbalances Treated the Same — The Ground is not the sky!”
    “Following the conventional architecture, the GCMs apply the solar response to all radiation balances to first order, where as we argue that the actual response to increasing CO2 is very different from the solar response.”


    Part 5: “Error 2: Model architecture means all feedbacks work through the surface temperature?”
    The intro says, in bold:
    This architectural feature is inherited by the GCMs.

    Now this is such nonsense that it makes people like Lucia and me, who do know about GCMs, think that you know nothing at all about them. GCM’s do not “inherit the architecture” of your made-up model. They are based on full 3D time-varying solutions of transport equations of conserved quantities – momentum, mass and energy. They are not based on the notions of feedback etc, or on differentiating anything with respect to temperature. The transport equations differentiate with respect to space and time.

    So “The Ground is not the Sky!”? A typical GCM will follow CO2 as it is transported through millions of grid cells, with maybe forty vertical layers. A radiative model will be solved with at least 100 points in the vertical, with data taken from those cells. And of course numerous spectral bands. The heat transferred to the GHG’s will go back into the cell data, and be redistributed in the next iteration of the energy equation. But your post 9 says

    Here’s a big big flaw that is easy for anyone to understand, yet has lain at the core of the climate models since at least 1984. Indeed, you’ll wonder why we all haven’t been chuckling at this simplistic caricature of our atmosphere for 31 years.

    I think you’ll find the chuckling is at your simplistic caricature.

    [Nick, see my reply at Comment 9.6. – David E.]


    • #

      “A typical GCM will follow CO2 as it is transported through millions of grid cells, with maybe forty vertical layers. ”

      So what about going down, into the ocean and the simple physical chemistry connection between surface temperature and CO2 exchange, the source of all life on earth and perhaps half the world’s new oxygen through phytoplankton? Do climate models really stop at the ocean surface, the source of all the CO2 in rapid exchange? What models exist to show atmospheric CO2 goes up with water surface temperature? Now there’s a known coupling. Then if ocean temperatures completely control CO2 levels, the whole AGW is bunkum.

      Remember that air temperature can change very rapidly. Water temperature cannot. So Murry Selby’s significant discovery that while CO2 does not correlate with temperature at all, it correlates perfectly with the integral of temperature. This is the energy impulse by incident radiation, measured by instantaneous air temperature, so perhaps no suprise and confirmation of the most significant and perhaps dominant mechanism controlling CO2 concentration.

      So while there is this argument about the significance of partial differentials and what is held constant, is anyone sure these models are even complete? What about the models of exchange of heat and gases from droplets? There is so much not there in these thermodynamic and radiation models. It has been known for half a century for example that tiny droplets from wavelets are responsible for much of the gas exchange at the ocean surface and possibly heat exchange as well. The only proof of any model is the fit to real data, past and future. How’s that going?


      • #

        SSSHHHHhhhh TdeF, can’t mention the ocean/CO2 interaction. After all the ClimAstrologists have declared the atmospheric CO2 residence time (lifetime) to be 50-200 years.

        Of course Dr. Robert H. Essenhigh and Dr. Tom V. Segalstad among others found a much more believable RT for bulk atmospheric CO2 of ~5 years. LINK


      • #

        Yes, many if not most of the current GCMs include multi-layer ocean circulation models, and small scale phenomena (below the gridded resolution level) such as gas interchange at the ocean/atmosphere boundary are handled with parameterizations describing observations of the chemical and composition relationships and changes. In other words, small scale parameterizations are a fit to the real data.

        Salby’s assertions are rather problematic, given that his math doesn’t hold up – if ocean solubility for CO2 were as sensitive to temperatures as he claims, glaciations would have shown zero (less than, if that were physically possible) ppm of CO2, rather than the observed 180-190 ppm – reductio ad absurdum. Claiming a non-anthropogenic cause for current CO2 levels is a really poor argument.


        • #

          if ocean solubilty for CO2 were as sensitive to temperature as he claimed

          I’ve watched all of Salby’s presentations and as far as I’m aware he never says that the CO2 increase is due to solubility changes of CO2. Only that the CO2 incrase is likely temperature induced. That is all. The change in water tenperature would need to be very large in order to explain the assumed 120ppmv increase (over 10ºC) according to Henry’s law. However that doesn’t mean to say that something related to temperature might not be contributing heavily, such as a decrease in ocean biological activity for instance. It’s estimated that if all biological activity in the oceans were removed the partial pressure of CO2 would increase by factor of 5, which would be enough to increase the CO2 concentration by 2,000ppmv (Jaworowski 1992). CO2 in the ocean and atmosphere exist in equilibrium and are directly proportional and so if ocean partial pressure increases that will force more CO2 into the atmosphere. So it is possible that small (temperature induced) changes in ocean biological activity could be contributing significantly to the atmospheric rise. That’s just one possibility, upwelling of carbon-rich warm ocean water is another.

          glaciations would have shown zero

          You’re assuming that CO2 changes in the atmosphere and temperature changes are lineraly related.


          • #

            “Claiming a non-anthropogenic cause for current CO2 levels is a really poor argument.”

            Says who? This is just ridicule, not logic.

            “The change in water temperature would need to be very large in order to explain the assumed 120ppmv increase (over 10ºC) according to Henry’s law”

            Yes, but this does happen in the tropics. +10C and it is always mid summer. Same water, same air, but a big difference. The world is not homogenous. CO2 output at the tropics must be incredible. In the arctic, the reverse as CO2 is absorbed, like all air. Still people go on about averages when there is no such thing as average water, air temperature. If you calculate one, you might come up with +1C only required to get vast amounts of CO2.

            The trick is that most CO2 is dissolved in the ocean, 50x that of the air. This is because of the massive increase of solubility of CO2 with depth.

            The IPCC argue that this cannot happen, that the CO2 dissolved at pressure in the deep ocean does not come into play as water currents take a thousand years to mix so you can ignore this vast reserve, but who said gas behaved like water? Bubbles come from the bottom. You do not need upwellings. A leaking of CO2 from the surface would be replenished from the infinite reserve. Then you have your explanation.

            As for Murry Selby, he does not propose an explanation, simply his conclusions on correlations from his observations. I am proposing an explanation and it adds up. Besides, as I can prove, there is almost no fossil fuel CO2 in the air and the lifetime of CO2 is measurable at 14 years. Personally I cannot see the point of writing papers for the obvious. Each person contributes according to his skills and David is making a model.

            However I am skeptical that Climate modellers have the whole picture or even that they matter. If CO2 is not changing world temperature and man cannot change CO2 levels anyway, it is all academic, like partial derivatives in a chaotic system.


    • #

      Dear Nick,

      Apparently you won’t find this “basic core model” in the IPCC.
      As written by David in the first post (emphasis mine):

      Developed by the 1970s, it is described in some detail in the otherwise-rather-brief Charney Report of 1979

      So David did not pick any model half way through anything.
      And I believe Jo’s answer to you in the comment you pointed at was about the following notion.

      It’s the model that is at the basis of the answer of the IPCC as to why they still think empirical mismatches do not matter much.
      Maybe the expression IPCC core basic model is unfortunate and you should probably not take it too literally.
      Indeed it is clear to me it is not an official, formal expression.
      It just reflects that the IPCC grounds the base and core of its answer on such a model.

      Again quoting David from the first post (emphasis mine):

      Despite the numerous mismatches between theory and climate observations to date, many climate scientists remain firm in their belief in the danger of carbon dioxide essentially because of this model, rather than because of huge opaque computer models.

      Now, I’m not jumping in because I think Jo and/or David cannot answer your questions.
      It’s because a) they already did, b) your comment has some wild claims in it.

      First David did not create that model. I really don’t know from where you gather such idea but it is wrong.
      Your basic objection is thus answered: this is not David’s doing.
      David has gotten into this model laid out by others; he did not set the stage up so that things would take a convenient turn for his criticism.

      Second, I fail to see why the models as teaching tools make David’s claims any less relevant.
      I hope you are not implying that they are only serious enough for teaching and thus this makes David’s claims only that much serious.
      That would be a new way to measure seriousness (not new in itself mind you. New in its effectiveness.)

      Also, you seem to seek an official, formal approval here as reflected by sentences such as

      No claim of a basic conventional model there


      Doesn’t sound like he’s recommending a conventional basic model for Earth climate.

      Do you understand that David, by discussing these papers, is actually delivering on his basic premise?
      That is we can find that the ideas of the basic core model (from the Charney Report of 1979) are indeed making their way in the climate science.

      You seem to dismiss this premise but you don’t actually deliver any substantial proof of that.
      And your discourse gets very messy.

      They are based on full 3D time-varying solutions of transport equations of conserved quantities – momentum, mass and energy.

      Well I really hope they indeed take such fundamental things as momentum, mass and energy into account.
      And I’m very pleased to learn scientists have understood things vary through time and also that 3D is better than 2D for modelling stuff about our planet.

      They are not based on the notions of feedback etc,

      David’s point exactly if I’m not mistaken.

      or on differentiating anything with respect to temperature.

      Well, first of all, the partial derivatives mentioned in this very article are performed with respect to temperature.
      Okay, I know this stuff is teaching stuff, no GCM stuff.

      But then: WTF?
      What are students being taught if it is not to be found in GCMs?
      Or, in reverse, why GCMs do not use the knowledge taught to students?
      Either way, you just scared me to no end.

      The transport equations differentiate with respect to space and time.

      Again, I’m glad they do. Seems pretty basic (not to do mind you. To have chosen to do.)

      A radiative model will be solved with at least 100 points in the vertical, with data taken from those cells.

      Err… great?

      And of course numerous spectral bands.

      So cool.

      The heat transferred to the GHG’s will go back into the cell data, and be redistributed in the next iteration of the energy equation.

      David’s point exactly if I’m not mistaken.
      All radiations get just pack as heat, general heat.
      And put back with no discrimination into the next iteration.

      Frankly, I can’t get your point of contention with David’s post series between your obvious statements of little argumentative value and the statements where you actually agree with him yet seem to not know that.


      • #

        “As written by David in the first post”
        Yes, David wrote that his model is described in some detail in the Charney Report. He’s wrong. It isn’t.

        “the IPCC grounds the base and core of its answer on such a model”
        Said again without evidence. If these things really were true, someone could quote them actually doing it.

        The argument seems to be
        1. Climate scientists do reasoning
        2. Here is some reasoning
        3. This reasoning has flaws
        4. Climate scientists are wrong.

        “What are students being taught if it is not to be found in GCMs?”
        Where is the logic in that? Students learning mechanics are taught about point masses, massless springs, frictionless blocks. Does that mean that all those limitations are in GCMs?


        • #

          The gist of this current answer is about validity, not soundness.

          If the Charney Report does not have the model David is referring to, then David is obviously wrong.
          If the IPCC does not base its answers on said model, then Jo is obviously wrong.

          My own way to read things is this.
          I do not answer based on what the argument seems to be.
          If there are some ambiguities, and there always will be, I try to find the most charitable line of reasoning in order to avoid attributing wrong or too extreme traits to the answer of my opponent or, any debater, really.

          The argument I have thus chosen for David is this:
          1. climate scientists have relied a great deal on simulations
          2. actual physical modelling is not always super clear

          => Intermediate conclusion 1 (IC1)
          It is not easy to pinpoint a clear physical model that could be used as a framework for discussion.

          1. climate scientists have relied a great deal on simulations
          3. simulations being overly complex, their use in debates tend to crawl them to a halt
          + IC1

          => IC2
          It is desirable to seek a better way to discuss things.

          4. we can find a basic physical model in the Charney report (and it’s not like we have a wealth of options)
          5. we can trace a filiation, at least in the same line of inquiry, in subsequent reports and many debates about climate
          6. climate scientists seems to back up their confidence on a physical model in the same line of inquiry as mentioned above
          + IC2

          => IC3
          Even if not perfect, this basic physical model seems the best relevant thing we can use to provide a ground on which to discuss the theory or at least the approach.

          7. there are various problems in the line of inquiry of the basic physical model, generally approximations we can’t hold satisfying given the high degree of inter-dependency of the climate system.
          8. these approximations appear in various papers whose scientific value is recognized in the field
          9. even if the goal of these papers is to only teach us things and can’t help to build models, it is interesting to question the assumptions behind these approximations for it is in no way assured we can’t learn something of value.

          => IC4
          It is relevant to discuss these approximations and propose alternatives.

          10. (okay I’m tired so I will pack things here) in climate science you find: boasting of huge confidence, avoidance or minimization of empirical mismatches, improper ways of debating about the approach (ad hominem and argument of authority cracking the top 10)
          + IC4

          => Conclusion
          There’s something fishy.

          As for the stuff about students and papers trying only to teach us things, I don’t understand what your point was.
          It seems you are saying that the papers only try to teach things and that they don’t pretend to be full-fledged models.

          For that argument (which is pretty unclear) to be of any strength, the most charitable interpretation that came to my mind was that there should be a gap huge enough between that they are teaching (like too simple, too approximate stuff?) and the real need of climate models.

          But then that would question their value because why teach and explore stuff that would be so remote from the real needs?
          I mean why spend time on them really?

          To which you could answer: my point exactly; David is wasting his time.

          But actually that argument would not work.
          Because on the one hand: first come, first served.
          Why in the first place climate scientists have wasted time on that and still do when they are getting back to akin physical explanations?

          And on the other hand, David is arguing to stop wasting time in the line of reasoning used in these papers and is actually proposing alternatives!

          Anyway, I do not have the time for such discussions about discussions.
          I’m sorry.
          It is not courteous of me to bail out but I really can’t spend much time anymore here.


        • #


          You deny that the conventional basic climate model is described in some detail in the Charney Report.

          It is on pages 7 to 9, where it can be reconstructed in its entirety from the text.

          Page 7: ΔQ is their symbol for the decrease in OLR from CO2 molecules when CO2 doubles, and they give the value as about 4 W/m2 per doubling (AR5: 3.7 W/m2 per doubling).

          Page 8: lambda is their symbol for the Planck feedback, and they give its value as about 4 W/m2 per K (AR5: 3.2 W/m2 per K). They give the surface warming as ΔT = ΔQ / lambda, which is the no-feedbacks case in Eq. (8) of post 2.

          Page 8 and page 9: Feedbacks are shown to modify the Planck feedback from 4 W/m2 per K to 1.7 W/m2 per K, so the feedbacks were thought to amplify the no-feedbacks warming by 4/1.7 or about 2.4, which is about the current estimate. The Charney Report estimates the ECS via this model as 1.6 to 4.5 deg C, likely 2.4 deg C, which is pretty similar to the ECS calculated in Eq. (18) of post 3.

          Same three ingredients (OLR blocked by a CO2 doubling, Planck sensitivity, and feedbacks), same connections/equations, and same result as the conventional basic climate model presented in post 3.

          Again Nick, you wrote nonsense that is easily disproved (see Comment 9.6) — are you trying to mislead readers here? Or was it another “accident”?


          • #

            “where it can be reconstructed in its entirety from the text”

            Why is it that the “basic convention al model” can only be seen when it has been reconstructed from text by Dr David Evans, one of the world’s leading climate change experts? Why can’t you simply quote a real expert saying that this is indeed the basic conventional model? If it is so “conventional”?


            • #

              Because, unlike you, I read the Charney Report? Nick your adamant claim in Comment 9.2.1,

              David wrote that his model is described in some detail in the Charney Report. He’s wrong. It isn’t.

              is false, isn’t it?


              • #

                To claim that your model is described in some detail in the Charney report is ridiculous. Section 3.1.1 simply describes radiative climate sensitivity ΔQ, as watts/doubling. They say
                “The value of 4 W/m2 is obtained by several methods of calculating infrared radiative transfer”
                Which is the “conventional basic model”? Then comes the temperature change, deduced on a black body basis.

                Then Sec 3.1.2 describes water vapor feedback, mentioning a fixed relative humidity, fixed lapse rate and fixed cloud cover to get a factor of 2. Then a bit more on snow and ice albedo.

                That’s it. Not a partial derivative in sight. How does that make a description “in some detail” of your model?

                But what they do say, in introducing 3.1, is (my bold):

                In order to assess the climatic effects of increased CO2, we consider first the primary physical processes that influence the climate system as a whole. These processes are best studied in simple models whose physical characteristics may readily be comprehended. The understanding derived from these studies enables one better to assess the performance of the 3D circulation models on which accurate estimates must be based.

                They are emphatically not saying that here is a basic model that you should use in preference to “huge opaque computer models”. They are offerring diagnostics.


              • #

                Nick, still got trouble reading? Two sentences before the quote you offer, the Charney Report (sec. 3.1.1) says:

                For a doubling of atmospheric CO2, the resulting change in net heating of the troposphere, oceans, and land (which is equivalent to a change in the net radiative flux at the tropopause) would amount to a global average of about ΔQ = 4 W/m2 if all other properties of the atmosphere remain unchanged. [My emphasis]

                You don’t have much luck with partial derivatives do you? It’s even holding everything constant, just like I said in post 4, and which you and Lucia have been denying and ducking ever since.

                Is the basic model important? Why is it even presented in the Charney Report? Reading further we find on page 12 (sec. 4) (thanks Thomas):

                Our confidence in our conclusion that a doubling of CO2 will eventually result in significant temperature increases and other climate changes is based on the fact that the results of the radiative-convective and heat-balance model studies can be understood in purely physical terms and are verified by the more complex GCM’s. The last give more information on geographical variations in heating, precipitation, and snow and ice cover, but they agree reasonably well with the simpler models on the magnitudes of the overall heating effects.

                Finally, note that the Charney Report uses the basic model to estimate the surface warming caused by a doubling of CO2 as (page 9, Sec 3.1.2)

                to lie in the range of 1.6 to 4.5 K, with 2.4 K a likely value.

                AR5 (p. 1033) gives the ECS as 1.5°C to 4.5°C. All that research and money, all those cpu cycles, 34 years on, and the establishment are still at where the basic model was in the Charney Report back in 1979. Well well.


        • #

          Nick Stokes October 21, 2015 at 4:39 am

          (‘Thomas, “As written by David in the first post”’)

          “Yes, David wrote that his model is described in some detail in the Charney Report. He’s wrong. It isn’t.”

          This is the exact evidence needed to verify that Nick Stokes is but a confirmed CCC troll. It is evident that he did not read the Charney Report or even ask his mommy to help locate and read such!

          (‘“the IPCC grounds the base and core of its answer on such a model”’)

          “Said again without evidence. If these things really were true, someone could quote them actually doing it.”

          The evidence is within each and every one of your GCMs as clearly represented by the output of such that are deliberately forced to increase surface temperature with increasing atmospheric CO2! Your GCMs via the Charney Report must reduce radiative exitance in the 13-18 micron band. This has been demonstrated over and over not to be the case. The radiative exitance in this band has increased slightly from the 100 ppmv value because of increased CO2 exitance from the stratosphere.


    • #

      In your opinion, do the GCMs work well now?
      Can these GCMs give us good information regarding near future temps?



    • #

      Nick – I would agree on all points. As I’ve said myself on these threads, finding faults with an incomplete model then claiming it represents architectural failings of all models is a strawman argument.

      [KR – Please see my reply to Nick at Comment 9.6. – David E.]


      • #

        Yes, KR. And besides, the ability of the models to track actual temperatures proves they have no failings. Oh, wait. They don’t match actual temperatures. You’re wrong.


        • #

          Have observed temperatures exceeded the 2-sigma variation ranges around model projections? No. While observations are cooler than the model mean, they are well within the range of short term variations seen in the models. And the observations are even closer to the model means given actual forcing variations over the last decade, rather than the estimates used in the CMIP5 runs (see Schmidt et al 2014).

          The ball falls within bounds – you cannot support a claim that models and observations don’t match.


          • #

            using 2 sigma, so 95 % of anything you project will be within bounds

            Why not widen it out and go to 3 sigma.. then it doesn’t matter what you project, you can say even cooling fits your projections

            Oh.. it is cooling. !!


      • #

        KR, read again (emphasis mine).

        (…) many climate scientists remain firm in their belief in the danger of carbon dioxide essentially because of this model, rather than because of huge opaque computer models.

        If that is indeed true (and quite some climate debates suggest it so), these climate scientists have authorized Mr Evans to perform his inquiry.

        It’s not that the incomplete model can represent well all models.
        It’s just that the scientists themselves flew away from all models to that one to justify their belief in the quality and promises of the CO2 hypothesis.

        In fact, this is exactly the reverse of the situation behind a strawman argument where a debater misrepresents the position of his opponent.
        Here, the opponent is weakening himself on his own by adopting a weak position, that is choosing an incomplete model to defend themselves.

        Granted, they do not rely on precisely that model.
        But the counter-arguments do find their root in such a model.

        Mr Evans is only performing classic scientific inquiry.
        Except that, rather than enriching the basic model to complete it, which seems to be what many climate scientists have done, he is revising it by changing things at a structural level.
        That’s a perfectly valid way to improve a model too, albeit a very transforming one.


    • #

      “A typical GCM will follow CO2 as it is transported through millions of grid cells, with maybe forty vertical layers. A radiative model will be solved with at least 100 points in the vertical, with data taken from those cells. And of course numerous spectral bands. The heat transferred to the GHG’s will go back into the cell data, and be redistributed in the next iteration of the energy equation.”

      These and the other points you made seem legitimate and should be addressed by David Evans. However, nothing will change the fact that Lucia, having taken it upon herself to criticize the specifics of Evans’ work, appears to have made some unacknowledged mistakes, as well as alleged specific mistakes on Evans’ part which weren’t.


    • #


      The conventional basic climate model (“basic model”) is ubiquitous in climate science. It is embedded in the climate conversation. It dates back to Arrhenius, and its ideas underlie all of establishment climate science. It is in the air. It is the basic mental model in climate, so pervasive that one might overlook it because it is everywhere. To question whether it exists is like a fish questioning the existence of water, or like not seeing the forest for the trees. Every student of climate science knows this model, at least implicitly.

      One can construct the basic model just from what “everyone knows”:

      • The Planck feedback is the starting point — e.g. “Climate models inherently predict climate sensitivity, which results from the basic Planck feedback (the increase of infrared cooling with temperature) modified by various other feedbacks (mainly the water vapor, lapse rate, cloud and albedo feedbacks).” RealClimate, 2011).

      • The Planck feedback is defined and calculated as per the basic model. It arises in the basic model as a partial derivative (see post 2 and post 3); it is the partial derivative of OLR with respect to surface temperature, under the Planck conditions (holding all feedbacks and drivers constant, but allowing tropospheric temperatures to change in unison while holding stratospheric temperatures unchanged, etc. (Soden & Held, 2006, pp. 3355-56)). The value of the Planck feedback is given in AR5, about 3.2 W/m2 (of OLR) per °C (of tropospheric warming).

      • The forcing due to CO2 is logarithmic in CO2 concentration, and a doubling of CO2 blocks about 3.7 W/m2 of outgoing OLR from CO2 molecules (if everything else is held constant — just like the partial derivative that arises in the derivation of the basic model, see post 2).

      • The forcing of CO2 is applied to the Planck feedback, obviously, like any other driver that causes a radiation imbalance. Forcings add, as everyone knows.

      • Feedbacks influence the surface temperature. They apply to surface warming, with units of W/m2 (of forcing) per °C (of surface warming). The total feedback value f is given in AR5.

      • Thus the feedbacks apply to the Planck feedback (which actually isn’t a “feedback” in the sense that that word is used in this discussion) in the classic feedback loop (Fig. 1 of post 3). Let the Planck sensitivity (the reciprocal of the Planck feedback) be λ0, in °C (of surface warming) per W/m2 (of forcing). Without feedbacks the surface warming would be λ0ΔI where ΔI is the total forcing (or radiation imbalance). But with feedbacks it is λ0ΔI / (1 – λ0f ). Look up “feedback” in Pierrehumbert’s index and it points you to the basic model.

      Which completes the construction the basic model – which is shown in Fig. 2 of post 3.

      Nick, now let’s turn it around. How would you feel if I presented the basic model of Fig. 2 of post 3, called it my model, and tried to take credit for it? That would be completely laughable, because as everyone knows, everyone already knows it. There is nothing in there that is original in the slightest. Yet you say to me “You have created that model” and refer to my “made-up model” — you are giving me credit for the basic ideas of climate science?

      Nick, do you claim unfamiliarity with the basic model? Never seen it before? Anything in there that surprises you perhaps? Would anyone you know in climate science be unfamiliar with any of the ideas in the model — the list of dot points above used to construct the model?

      I am claiming that the basic model, the very air of establishment climate science, is poorly architected. Before critiquing it and proposing changes to its architecture, I have to define it exactly. So, as per the Charney Report, the leading theorists, and the leading textbook, with support from AR5, I did that in post 2 and post 3.

      Nick, your Pierrehumbert reference is misleading and wrong. I wrote and you quote me: “pages 163–165 of the “gold standard” of climate textbooks, Raymond Pierrehumbert’s Principles of Planetary Climate” and the reference given is “Pierrehumbert, R. T. (2010). Principles of Planetary Climate. Cambridge: Cambridge University Press.”. This is section 3.4.2. It is in Chapter 3, which is titled “Elementary models of radiation balance”, section 3.4 “Ice-albedo feedback”, subsection 3.4.2. “Climate sensitivity, radiative forcing and feedback”. Seems like the relevant section for the basic model in Pierrehumbert, perhaps?

      Your nonsense about a “Grey Gas Model” and that Pierrehumbert “is talking about general planetary atmospheres” is either mischievous or very careless – you didn’t read your section to see that it contained the basic model, did you? Hoping perhaps that readers here would not bother checking?

      We’ll get to GCMs in a later post, after this series is finished. But yes, the pervasiveness of the ideas of the basic model mean that the GCMs do have much the same architecture with respect to forcings (absorbed sunlight and CO2 forcing have much the same effect — if forcings from different influences were thought to have had wildly different effects on surface temperature, why bother with tallying up forcings if GCMs didn’t do something effectively similar?) and feedbacks only in response to surface warming (yes there are a few minor exceptions, but nothing major like the rerouting feedback of post 7).

      Nick, you say “Now this is such nonsense that it makes people like Lucia and me, who do know about GCMs, think that you know nothing at all about them.” If you stopped worrying about your exalted status as an expert, and listened to other voices, you might learn something. For instance, although you and Lucia made derisory comments about me over partial differentials (e.g. Comment 139671), you look foolish now because it turned out I was entirely correct on the partial differentials.


      • #

        Joanne must be very proud of you now! Congrats.
        Planck’s wonderful equation for one single absolute temperature is precise for “maximum planar surface” specific intensity, spectral radiance, or spectral exitance under conditions of NO opposing specific intensity or spectral radiance.
        What the CCC miss is that the Earth is not isothermal, is not planar and is not a surface. Planck’s equation is simply not applicable to this Earth and its atmosphere.
        A modification of this with appropriate wavelength intervals can be made precise enough for exitance at each waveband and each direction from this planet relative to the direction of the sun and to the seasons of the year! In this reference frame longitude (rotation but not direction) is eliminated. The 12 hour Lunar thing becomes a internal modulation Now all internals remain internal to the system and all externals are measurable. Such sets would be completely verifiable from external satellite observations. Even a precise directional specular insolation and albedo would be easily measured! We now have sufficient knowledge of just what to measure from what direction, to maximize learning.
        We can only demand (with pitchforks) such be done before the CCC zelots destroy us all.
        All the best! -will-


      • #


        ‘One can construct the basic model just from what “everyone knows”:’

        The key word there is construct. Yes, there is a lot of commonality about the ways that people think about the atmosphere. But they don’t put it all down and claim it is a “basic conventional model”. You did that. The reason they don’t is that they are aware that the concepts are exploratory. They have limitations. When you construct and formalise the model, you build in some set of limitations. Subject to those limitations, the model can be useful. But you have described the limitations you built in as errors 1,2,3, and say they somehow undermine climate science.

        Pierrehumbert indicates that status directly. I talked about the grey gas model, because they were the page numbers you directed me to, and I used the link you supplied. But OK, let’s look at pp 135-138 in the pdf you linked. I’m now looking at “3.4.2 Climate sensitivity, radiative forcing and feedback” in a section called “3.4 Ice-Albedo Feedback”. He starts the section with

        The simple model we have been studying affords us the opportunity to introduce the concepts of radiative forcing, sensitivity coefficient and feedback factor. These diagnostics can be applied across the whole spectrum of climate models, from the simplest to the most comprehensive.

        So again, it’s a teaching purpose. He is introducing the concepts of “radiative forcing, sensitivity coefficient and feedback factor”. They are diagnostics. That is an important point re GCMs. People have the notion that they are the basic inputs to GCM’s. They aren’t. GCM’s couldn’t use them anyway. GCM’s use fields defined for each cell in the grid. But you can use them to interpret the output.

        But in the preceding para, he puts his notion of model in context:

        The simple models used above are too crude to produce very precise hysteresis boundaries. Among the many important effects left out of the story are water vapor radiative feedbacks, cloud feedbacks, the factors governing albedo of sea ice, ocean heat transports and variations in atmospheric heat transport. The phenomena uncovered in this exposition are general, however and can be revisited across a heirarchy of models. Indeed, the re-examination of this subject provides an unending source of amusement and enlightenment to climate scientists.

        The “too crude” model is the one he’s using in this section. He;s clearly not recommending that you go out and model the atmosphere with it. But you can use it for “amusement and enlightenment”.

        ” For instance, although you and Lucia made derisory comments about me over partial differentials (e.g. Comment 139671), you look foolish now because it turned out I was entirely correct on the partial differentials.”

        You are totally misguided, and at a very elementary level. I pointed out, with some derision, that your basis for Error 1 in Part 4:
        “Partial Derivatives of Dependent Variables are Ambiguous”
        was given as:

        When a quantity depends on dependent variables (variables that depend on or affect one another), a partial derivative of the quantity “has no definite meaning” (from Auroux 2010, who gives a worked example), because of ambiguity over which variables are truly held constant and which change because they depend on the variable allowed to change.

        But in fact, in that introductory lecture, Auroux is not describing an inadequacy in the meaning of partial derivatives. He is describing an inadequacy in the notation that he has used to date, and introducing an standard extension (suffix) which removes the ambiguity. He says

        “There is only one way out of our difficulty. When we ask for ∂w/∂x, we must at the same time specify which variables are to be taken as the independent ones…”

        The answer is notation, not despair.

        And so you go on to:

        “The notion of “holding everything else constant” can be ambiguous or arbitrary in climate. Because the climate variables are so interconnected, it may be impossible to plausibly and unambiguously hold everything constant except two variables.”

        Why only climate? If it is a problem in the concept of partial derivatives, it would be a problem in all the sciences where they have been used for 200 years. But the idea of “holding everything else constant” is just a basic technique for puting numbers on multivariate change. You need to get a set of actual numbers to describe it. So you look at changing one at a time, Then you can put it all together. The surface you are describing doesn’t change by the way you do that.

        An analogy is coordinate geometry. You have a set of triangles or whatever. You set up (x,y) coordinates. That means you define x,y axes (maybe not orthogonal), and say, for the coordinates of point P, proceed a distance along the x axis, holding y constant, and then parallel to the y-axis, holding x constant, till you reach P. The distances make up the coordinates. Then you can work out all kinds of stuff. You’d get the same results whatever axes you used. Your understanding of the geometry is in no way limited by the step at which you held y constant. In fact, the role of that notion in partial derivatives is just to define the coordinates of the vector derivative.

        This is really basic stuff.


        • #

          Nick, still misleading onlookers, changing the topic, and hiding behind notation?

          You and Lucia haven’t admitted you were wrong and that Held, Soden, Pierrehumbert and I were correct in applying a well-known method of differentials. Or that Lucia’s trickiness with creating a notation for the part of OLR that does not vary with drivers and feedbacks was just legerdemain — other people have the Planck feedback and Lucia has … the same number, calculated the same way, but with no partial derivative symbols! Still trying to tell us you are an “expert” and “This is really basic stuff.” I think people get the drift…

          Your previous argument that I invented the conventional basic climate model has morphed into “other people know it but only I wrote it down”. Well yeah, apart from the authors of the Charney Report, Held and Soden, Pierrehumbert, and a zillion others.

          You say the others only use it for “exploratory purposes”. Right, like in the Charney Report for instance, which largely kicked off the CO2 scare in 1979 and used the basic model first up as its first argument that CO2 was a problem, before two early computer simulations. Read post 1 on why the basic model is so important — you think the world is convinced by opaque huge computerized climate models, or the simple application of basic physics? You don’t really have an argument do you Nick — like with the differentials, you only have scorn and bluff.

          Nick, I gave you the right page numbers for Pierrehumbert, you just mixed up the different page numbers for the PDF and the book references. You quoted the wrong part (and didn’t notice?). Grey Gas models have nothing to do with it. Can’t you even admit that?

          You still seem to think I’m constructing the model from scratch (the same one that’s been in textbooks for decades), saying that I “build in some set of limitations.” But I didn’t make any limitations – they come with the basic model. I’m just identifying them. Discovering, as it were, what others have “built in” but may not have explained in so many words.

          Your carelessness is starting to leave a trail. You’re quick to say I’m wrong about the Charney Report, but when I cite the pages and how they construct the model (Comment you’re slow to acknowledge your own error (we’re still waiting). Are you here for an honest conversation or something else? (Did you even read the Charney Report?)

          Nick, you again avoid the argument on the existence of the Planck feedback partial derivative, and the wisdom of basing the basic model on it. You would try to mislead onlookers into thinking the complaint about partial derivatives was merely about notation, and Auroux’s notation of explicitly noting the variables to be held constant could solve the problem. What baloney. The problem is physical – one cannot hold feedbacks and drivers constant in climate while allowing only surface temperature and OLR to vary. Go hold back the tide.

          And what a weak and transparent shift to pretend that just because partial differentials work in say, fluid flow or electromagnetism, then they must work in the climate. We’ve been through this before (see post 1): in most fields of science, models that fail get dumped. It’s only climate science where failure lives on for four decades and get a Nobel Prize.

          But then you probably don’t want to talk about model validation do you — just hoping to change the topic from your own overconfident incompetence with partial derivatives?

          As you say, “this is really basic stuff” –- but it’s more basic than you think. Let’s start with references, manners, honest acknowledgement of errors, and reading accurately. Anything less, and people might start calling you a troll.


          • #

            The 1979 Charney report is indeed interesting reading – but the sections you discuss, and values presented in Section 3 that you discuss, are the results of many different and consilient lines of investigation: radiative-convective codes, satellite observations of atmospheric termperature profiles, GCMs, heat-balance models, spectroscopy, surface humidity measures, etc.

            And, as they clearly state in Section 4, page 13, “We proceed now to a discussion of the three-dimensional models on which our conclusions are primarily based.” – Section 3 on the physical processes is a description of results, and a good introduction of the uncertainties and difficulties.

            It is, however, not the starting point for their modeling estimates. Nick Stokes is quite correct in pointing that out.

            While it should go without saying, it’s probably worth noting that that represented the state of climate science 36 years ago – and ongoing observations and developments in climate science have only refined such early estimates.


            • #

              You seem to try to imply from yet another perspective that David’s choice for his criticism is wrong.
              Wrong or right does not matter because it – is – not – David’s – choice!

              Remember David’s first post (emphasis mine):

              many climate scientists remain firm in their belief in the danger of carbon dioxide essentially because of this model, rather than because of huge opaque computer models.

              And… please be serious!
              Here’s a quote from Section 4, page 12, so a bit sooner than yours (emphasis mine):

              Our confidence in our conclusion (…) is based on the fact that the results of the radiative-convective and heat-balance model studies can be understood in purely physical terms and are verified by the more complex GCM’s. The last give more information on geographical variations in heating, precipitation, and snow and ice cover, but they agree reasonably well with the simpler models on the magnitudes of the overall heating effects.

              So yeah, even if they seem to say they start on GCM (based on your quote), they also say that their results amount to about the same as the results of the simpler models.

              So are they right or are they right?
              Either way (which is, really, the same way), it’s pretty clear David’s inquiry is valid and sound.


              • #

                You quote “Remember David’s first post (emphasis mine):”

                many climate scientists remain firm in their belief in the danger of carbon dioxide essentially because of this model, rather than because of huge opaque computer models

                for which he gives no evidence (nor do you).

                Yet when KR reports the Charney Report saying exactly the opposite

                “We proceed now to a discussion of the three-dimensional models on which our conclusions are primarily based.”

                you give quotes saying that the 3D results agree “reasonably well” with the results of simpler models (note the plural). And you try to twist this into saying that they thus rely on the simpler models.

                You see this attempt to reverse logic elsewhere in this series. David uses some IPCC numbers in his model. So it becomes an “IPCC core basic model”. But in fact, despite their alleged preference for David’s “basic conventional model”, the IPCC reports are full of discussions explicitly relying on the “huge opaque computer models”. The “core basic” model isn’t cited at all.


              • #

                The quote I gave answers all your objections.
                Models help them understood stuff. And they are verified by GCMs.
                And they primarily based their inquiry basing themselves on GCM because, obviously, they gave more information than the simpler models.

                But you want zero relevance about these models.
                You want to reduce any link to them to nothingness.

                So they are just teaching materials.
                So they have no relation to how GCMs operate.
                So they are diagnostics on the ouputs of GCMs.
                So they are used for amusement.
                So they have been refined so much.
                So GCMs have been preferred to them.

                They have appeared in the mainstream literature, as one possible starting point long ago.
                For that reason and that only reason, David is perfectly justified to go back to that point, investigate and choose different directions at each turn where the mainstream direction is displeasing him.

                Again and for the last time, this ain’t a strawman argument, this is scientific inquiry.

                Adieu, Nick.
                Adieu, KR.


          • #

            I haven’t read all the comments here, and likely won’t as the thread is so long and life is so short… but I’m going to stick one small oar in the water here anyway.

            It’s about models “inheriting” things.

            First off, a disclaimer. I’ve not read every line of code of every model. One some of the code of a few of the models. Much of my assertion is about “the usual programming practice” mixed in with some decent speculation based on what GCM code I have looked at. Then there’s a link to some actual historical fact.

            Everyone starts from prior art when writing new large code bases. At a minimum you look at what was done before from the outside to see what already exists and what didn’t work well and needs improving.

            It is even more strongly done in “open source” communities and in university research and government research circles.

            The code itself shows heavy “borrowing”. The one I’m most familiar with (not a GCM, but still a ‘climate code’) clearly has sections that are shared with NCDC (prior to the name change).

            Looking inside some of the other codes ( it was one I downloaded from Hadley some years back) there were clear epochs of creation in the code. Added modules as grad students came and went, IMHO. Grown over many years (perhaps to decades). Other models would make reference to prior art in their explanatory docs and comments in the code. Saying things like “We are grateful to FOO for the code in BAR section” or “for the work done on…” and citing another code or author of another code.

            How pervasive is it? I can’t say. As noted above, I didn’t go through all the codes line by line and memorize them. But I can say even a cursory examination shows significant “borrowing” over time, each from the other. Here’s one example just from inside Hadley:

            The historical evolution of GCMs, computing resources, and the nature of climate change
            experiments, are inextricably linked. This evolution of the Hadley Centre models can be viewed
            in a historical context through as shown in Table 1.

            Table 1: Evolution of the Hadley Centre GCMs (see text for explanation of the terms)

            Model Name and Experiments Year Ocean
            lat. x long.
            Equilibrium 10 year integration 1987 Slab-ocean 5.0 x 7.5
            Equilibrium 10 year integration 1990 Slab-ocean 2.5×3.75
            Transient cold-start
            Multi-decadal integrations
            1992 20 layer full ocean 2.5 x 3.75
            Transient warm-start
            Historically forced
            Multi gas
            Multi-century integrations
            Multi-member ensembles
            1995 20 layer full ocean 2.5 x 3.75
            As HadCM2 but including gas life cycle
            and early version of a biosphere model
            No flux correction
            20 layer full ocean
            2.5 x 3.75
            Note: For further details of the Hadley Centre’s GCMs, climate change experiments
            and available data sets please see the Climate Impacts LINK Project

            Note that it says GCMs, plural. And “evolution”. Over a decade of models each building on what was written before.

            It also isn’t just inside one shop where ideas get ‘borrowed’. See this article on the history of models:

            Groups continued to proliferate, borrowing ideas from earlier models and devising new techniques of their own. Here as in most fields of science, Europeans had recovered from the war’s devastation and were catching up with the Americans. In particular, during the mid-1970s a consortium of nations set up a European Centre for Medium-Range Weather Forecasts and began to contribute to climate modeling. A “family tree” of relations between leading models is here.

            One doesn’t need a “family tree” if there is no “family”…


            While reality is not as simple as David paints with his implied direct line inheritance, it is not all clean room isolated as Nick implies. In reality, most of the models trace back to two common roots. One at UCLA and the other the Philips model. They ‘cross fertilize’ about 1975 and that mix leads to most of the end points today. UKMO being a distinct line outside that mixing (but with sharing of ideas via “the literature” and conferences and…) along with NMC as a separate line (with similar pollination of ideas via “industry practices”).

            16 of 21 models listed have lineage back to Philips / UCLA, while 2 are UKMO and 3 are NMC based.

            It is not in any way a stretch to say “they’ve met” when looking at models today. These are NOT independent clean room creations.

            In informal writing, to state that ideas have been inherited from the start, glossing over the full map of inheritance and the UKMO / NMC outliers, is not at all an unreasonable thing to do. Frankly, Nick’s attack on it is far more tedious. There IS inheritance and there IS clear history of it and there IS clear “group think” in the community of development. There is no need for David to write a book on just that to prove the point. Doing that for each and every minor point would consume a few lifetimes and add nothing.


            • #

              ” it is not all clean room isolated as Nick implies.”

              Where did I imply that? Of course the GCM’s are related. They usually say that they are following various fairly standard papers for their components, so they should be. And their roots are in CFD codes and their application to weather forecasting.

              What I did say is that they do not inherit their structure from a model like that which David has put together. They have very different functionality. David’s is reduced to essentially zero dimensionality, and is quasi-steady. GCMs are all about variation in time and space. Most of the differentiation is with respect to those variables. They solve transport equations on a grid or other discretisation. There is no place to put in notions of feedback or global sensitivity.


        • #

          Okay, I couldn’t resist but check in today.

          Your discussion on model is very tiring.
          And the terminology is so… I don’t know.

          I’m a computer programmer with a strong background in formal and applied mathematics.

          The notion of concepts being diagnostics is ridiculous.
          You can certainly use them to diagnose but nothing is stopping anyone to use them in another way.

          And when you wrote diagnostic and interpretation of output of GCM, I thought: this is about programmers trying to debug and understand their programs.
          Is this a new kind of scientific methodology?

          But I’m more inclined to put my money on good old fashion reality checks.

          I am also very tired on the partial derivatives stuff.
          The calculus Lucia made is very simple.

          It shows that when you have a variable unrelated to the one against which you perform the derivation, you can set a value before or after the derivation.
          Nobody cares.

          To reuse the vocabulary: it can be set to a constant before or after.
          That’s because an unrelated variable is treated like a constant during the derivation.
          So its status of being a variable or a constant is irrelevant.

          Your example is spot on with the point Lucia made.
          But it has nothing to do with what David is saying.

          A related variable cannot be treated lightly during the derivation.
          So if you set its value beforehand, making it constant, you will then perform a wildly different (and simpler) derivation.

          To modify your example properly, David is saying that the movements you are doing on the y-axis are dependent on where you are on the x-axis.
          The value y can take are dependent on the value of x has taken.

          Like for a mountain.
          If you first move on the x-axis to get to the sides of the mountain, moving forward along the y-axis will be easy.
          But if you don’t care and rush head on on the y-axis, well, let’s wish you to not point exactly to the summit.
          That would a difficult path, maybe an impossible one even.


          • #
            • #

              David (and Jo),

              You have my deepest respect for the courage and patience you put up with some people.
              I am flabbergasted by the level of dismissive writing (which is fine) coupled to a total absence of proposal of alternatives (much less fine).

              I have followed the blog for quite some time now but only reacted here because the math stuff falls directly in my area of competency.
              The basic problem is so easy to understand (when you have the appropriate training that is) that I couldn’t believe my eyes.

              I never thought people could be so uncharitable as to put the burden on everybody else to clear up even the most basic reasoning connections and to be so dismissive from the ground up, above common sense and above the basic right for any kind of intellectual inquiry.

              I won’t make the mistake to engage such people again.

              Thanks for your much needed blog!


  • #

    […] Lucia has a bad week on partial derivatives […]

    [This pingback is from Lucias update just added to her post, to which David has updated our post above. -J]


  • #

    The problem with the “not invented by me” mentality, is that they can’t stop digging even though they’re obviously already in a deep hole. Frankly, arguing with some of the finer points of Calculus as it’s applied to a complex system like climate by a mathematician, is right up there with a one-legged man (or woman in this particular case) entering an ass kicking contest.



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      Rud Istvan

      Agree. Tried to help in the first round of this sideshow, and failed. Army’s first rule of holes applies. If you are in one and want out, first thing to do is stop digging. Lucia apparently was never in the Army.


  • #

    Maybe this clip from Groundhog Day will lighten the mood. Start at about the 1:55 mark.

    Phil “Jo-David” Connor: “Do you want the truth about partial derivatives, or are you just scoring snark? ”

    Mrs. “Lucia” Lancaster: “Just scoring snark”.


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    Joe Born

    I confess to reading most blog posts only superficially. But occasionally I do dig into things, and on one such occasion Dr. Liljegren horned in and betrayed herself to be a lightweight. I nonetheless visit her site occasionally in attempting to heed Max Ehrmann’s injunction to “listen to others, even the dull and the ignorant; they too have their story.”

    And in this case I’m inclined to the approach some others on that site seem to have adopted: although my superficial perusal of the head post here suggests that Dr. Evans may be right in some sense, I’m not going to analyze the partial-derivative issue closely enough to be sure until this series has convinced me that the issue will ultimately matter.


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    “but they could’ve done it a different way without them”

    I’m dating a woman who is a physicist with a bachelor’s of mathematics and we have had so many conversations about this. Most of these have not been about climate science (some have been), and instead they’ve tended to be about astronomy, cosmology, and consciousness (but I repeat myself).

    There is a strong bias in science toward using math to explain things, but here’s the problem. Many things are too complex to explain with our current level of mathematical expertise (and many are probably non-computable, per Goedel’s incompleteness theorems).

    So do people say, “We don’t know?” No, they apply the math they know how to do, which frequently gives non-physical answers to problems. Then they give each other Nobel prizes and peer-review each others’ papers.

    But they’re often on the wrong track entirely, or, at least, produce poor models.


    • #

      Also, to be clear, the other option other than, “I don’t know,” is to spend more time thinking about the architecture of the system, as David Evans said the other day. But, instead, we often reduce things to mathematical abstractions that are hard in the sense that they’re complex math for 2015 humans, but don’t begin to describe what’s going on in the physical world.

      For example, we treat electrons as points with charge. But, they appear to have structure and their dipole moments are important in London forces, Van Der Waal forces, as is now well understood in chemistry. What is not well understood at the moment is that electron dipole moments are probably important in gravity as well.

      At some point, this all relates to climate, among other complex natural systems.


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      I don’t agree. Biology is every bit as majestic a science as physics (and I speak as a physicist) but its language is not fundamentally that of mathematics.


  • #

    “Is not that holding ice, cloud, and water vapor constant?”

    Yes, obviously. She’s managed to, in one formulation, reduce the amount of symbols used. Then she confused symbols with physical reality, forgetting that the lesser number of symbols refers to a greater number of physical things.


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      Right. I suspect her splitting of R into those two terms can be done only on paper, that Rₚ is without physical meaning.


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    Though it’s been many years since I wandered through the pages of Kamke’s Differentialgleichungen, Lösungsmethoden u. Lösungen, I’m of the opinion that Dr. David’s count of the angels on the head of this particular pin is the correct one. Amen.

    Meanwhile, in the real world, the Pope is spreading AGW propaganda to millions of innocents. Why are we not sending copies of some skeptical work to priests around the world? I’d suggest “The Hockey Stick Illusion,” but there may be better choices. The point is to DO something!


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      Ava Plaint

      By Jove, that sounds like work for the Knights of St. John.
      What self respecting priest would dare to risk being caught with a copy of The Skeptics Handbook under the covers.
      The heroic Bible smugglers of soviet Bloc Eastern Europe spring to mind.


  • #
    Svend Ferdinandsen

    Could it be that Lucia and David both have right, it is just the assumptions that differ.
    I have it hard with Davids discarding of partial derivatives because of some dependent variables.
    It would turn up when you use them, or you should get rid of the dependent variables before any partial derivatives. Anyway, at least in climate, it could be hard to really define the right dependency, and that leaves you back at square one again.


    • #

      “Could it be that Lucia and David both have right, it is just the assumptions that differ.”



    • #

      David is not really discarding the partial derivatives.
      Yes, it is easier to do the calculus by supposing variables are independent (or: things are held constant regardless of what the temperature is doing).

      But David notes that doing so obviously make the whole calculus a rough approximation.
      What he is actually discarding is the fact that for the climate system, it is more than a rough approximation.

      Things are seemingly intertwined in significant ways in the climate system.
      So we can’t reasonably feel satisfied with such an approximation.


  • #

    Lucia has confirmed your way of doing the math is OK. Anyway, as an engineer, I’m sure you are used to formulating problems in a certain manner. Also, regardless of the genesis of the “basic climate model,” you have specified exactly what you mean by that and how your approach is different.

    For the time being, I think you should ignore her. I would like to see the next post or three so we can get to where we are going. After that, there will be plenty of time for tit for tat.


  • #

    They say the best propaganda has a decent % of truth in it.

    As such, are we seeing the new model effectively attacked by creating enough F.U.D. and thus creating sufficient uncertainty so that the new model now requires more energy being put into defending it, thus stopping its development?

    Clever, no?

    Perhaps the answer is to push on, ignore the sniping and put your energy into a game changer, and argue once its done….


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    It is not necessary to respond in line with the wrecking ball known as Lucia. Fer crapsake, finish your story, David. Lucia can wait – there’s plenty of time to deal with her from the other side of your completed story. This is the same trap you fell into with Willis on your first go-round. Ignore the graffiti and soldier on. No segment of this story makes sense until the entire story is told. Quit being so damned polite and get on with it.


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    My favourite way of pointing out to people like Lucia that partial derivatives are more subtle than they seem is that, if a 1:1 relation between x and y exists, which can without loss of generality be written as F(x,y)=0, then

    dF = (DF/Dx) dx + (DF/Dy) dy = 0

    (where D denotes the partial derivative, usually written as a curly ‘d’, and by convention when differentiation of F is with respect to x then y is held constant, and vice-versa), so that

    dy/dx = – (DF/dx)/(DF/Dy).

    Naively one would not expect the minus sign on the right-hand side.


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    Chris Lynch

    This may have already been said–if so, I apologize.

    I posted over at Lucia’s comment section an observation about her first two quotes of Dr. Evans’ post: the first quote presents the problem with *partial derivates*, which refers to the MIT paper. The second quote, if I understand correctly, is essentially a repeat warning about having arguments to the function be related to each other, but uses “differentials” instead of “derivatives”.

    If I understand everybody correctly, it looks to me as if some folks here have confused differentials with derivatives–the problem Dr.Evans mentioned exists with derivatives, but NOT with differentials, according to the MIT paper referenced above.


    • #

      Don’t think so Chris. Note that the application of differentials and partial derivatives here is as per the textbooks and peer-reviewed papers. Not us with the problem.


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    G.M. Jackson

    I’m a bottom-line kind of guy. If your alternative model works better than the conventional, Lucia’a points will be immaterial