IPCC models have failed to correctly deal with changes in air density

Canadian scientist Dean Brooks has written a provocative paper pointing out that GCM’s have not handled atmospheric density changes correctly. You can download his 1MB pdf paper “The ‘Pot Lid’ Hypothesis: Where Does the Air Go?”.

He has also written and published on “The Decline Effect – The law behind diminishing returns and wildly varying outcomes in markets, politics, culture, religion, disease, and war” – his 30 odd page Chapter 1 is downloadable, only 400Kb – Looks like a must read.

8 thoughts on “IPCC models have failed to correctly deal with changes in air density”

  1. Its rare to read a scientific paper as well written as this.

    In summary it says the +ve water vapor feedback in the climate models is an artifact of not correctly incorporating the gas laws into the models. A longer term +ve water vapor feedback is physically impossible.

    I’d make one observation. Dean seems to think his discovery of the flaw is somehow unusual in the history of science. It isn’t. This is the usual way science progresses – Kuhn, Paradigm Shifts, etc.

  2. I’m glad you think it is well written. Many thanks.

    About whether finding a flaw like this is an unusual event — I think science is often exceedingly messy, and progress in it can be uncomfortably random. I like to cite Feyerabend as well as Kuhn, if that helps illustrate my view. I had a little historical note which I dropped from the final draft, about abrupt reversals like the discovery of continental drift. The “overwhelming consensus” suddenly fell apart in that case too.

    But in that case we at least had new data! We sent cameras to the bottom of the Atlantic and filmed new crust spewing from the seafloor, and that changed everyone’s mind in a hurry. This is closer to a calculation error not being caught for 50 years.

    Maybe I just find it especially unnerving and unusual because I’m the guy who found the error. Anyway, thanks again, and thanks to Warwick for posting the link.

  3. Dean,

    One other observation.

    Climate science is post-computer age science where the significant products (climate models and predictions) result from the collaboration of large numbers of scientists. Where no one scientist fully understands the whole and only a small number understand an individual part.

    It happens I worked for many years on large scale software projects and observed that groups that worked on components of the larger system would rarely, if ever, question collectively held assumptions, and would collectively resist others questioning their assumptions.

    My reference to Kuhn was a reference to how it is the work of outsiders that usually overthrows paradigms. Not those doing ‘normal science’.

    I could go on at length, but would say in summary that the complex fragmented nature of climate science makes it particularly resistant to paradigms being overthrown.

    Then there is the politicization of climate science over the last 20 years.

    It doesn’t surprise me an error like this has persisted for 50 Years.

  4. An expanded and corrected version 2.0 of the essay is now available at www.declineeffect.com.

    In the previous version I skipped over many of the details of how a GCM works and went rather too abruptly to the conclusion, that air cannot be transferred between layers to produce the vertical density shifts caused by warming and by water vapor uptake.

    The new version includes several pages to clarify why convection in a GCM involves elaborate calculation of mass fluxes, but does not actually move air between layers (the Arakawa-Schubert method). It also explains why circulation in a GCM does move air between layers, but not enough or in the right places to avoid the exaggerated warming forecast.

    Reader feedback has been most helpful in identifying weak or obscure parts of my argument. I hope that will continue.

    Thanks again to Warwick Hughes.

  5. I notice this paper at Tallblokes blog;
    Nikolov & Zeller — Unified Theory of Climate
    From their Abstract,
    “…the so-called Greenhouse Effect is in fact a Pressure-induced Thermal Enhancement (PTE)”
    I was reminded of the “pot lid” paper – by the Canadian Dean Brooks.
    Perhaps some readers could opine as to if there are similarities between Brooks and Nikolov & Zeller.

  6. I have been reading Nikolov-Zeller and the blogosphere’s reaction to it. I will need a little more time to completely digest their arguments, but I would say two things right off the top of my head:

    1) My argument is not a complete theory of climate. To recap, I argue that because density data have always been hard to obtain, climatology has spent the last century making the simplifying assumption that the atmosphere is essentially hydrostatic, with no long-term trend of vertical density shifts. This assumption has been very fruitful in simplifying weather models, but it should have been reconsidered in the 1960’s when global warming was first advanced as a theory.

    A 3-degree rise in average temps entails a 1 percent increase in sea level temperature AND a 1 percent decrease in sea level air density. That air has to go somewhere. The models mishandle the process and so produce a non-existent “hot spot” in the upper troposphere as well as positive water vapor feedback.

    It’s a very serious problem but pointing it out doesn’t amount to a general theory of climate, rather a critique of the mainstream theory. If the modelers ever published plots of density change in the troposphere, it would be obvious something is wrong with the models, because density is decreasing everywhere in the troposphere. How is that possible? Where does the air go? This is what ‘Pot Lid’ is about.

    2. I think there is a useful connection between Nikolov-Zeller and myself, and also with Miskolczi’s “saturated greenhouse” model, which has been simmering among skeptics since 2007. However, the connection is rather obscure and will take a fair amount of explanation. I will make a start here. Please understand that I am pressed for time and that I will likely have to expand and amend this argument later.

    Miskolczi has argued that upward radiation into the atmosphere, Aa, and downward radiation from it, Ed, are so close together in value that in practical terms the Earth cannot shed significant energy by radiative transfer to the atmosphere. It must either escape via the “window” or else via convection/evaporation. He then introduces another empirical radiation law, in which total radiation upward from Earth Su is equal to 2 x Eu, the total radiation emitted upward by the atmosphere. This further restricts the atmosphere’s response (by limiting total evaporation) and brings on “saturation”.

    Miskolczi is a “pressurist” (if I may use that term) in somewhat the same sense as Nikolov-Zeller. He sees the Aa-Ed balance as being set by the overall weight of the atmosphere pressing down at sea level, and likewise sees the Su-Eu balance as controlled by the virial theorem, which relates gravitational potential energy to heat energy.

    After much thought I have realized he is right, that the Aa-Ed and Su-Eu relationships do control climate, and pressure is central. But it is also clear to me that both of these relationships really exist because of density considerations.

    I will set aside Su-Eu and focus on Aa-Ed. Consider an alternate Earth with the same fixed proportion of greenhouse gases, but with 10x the total atmosphere. Would heat escape more easily, or less easily?

    If we increase pressure 10x, we increase density by a similarly large amount. Optical density of the atmosphere is a function of mass. A 10x denser atmosphere will bring sufficient mass to block escaping radiation about 10x closer to the ground. Given a constant lapse rate, this means that the temperature gap between air and ground will be smaller. And thus the small Aa-Ed gap will become even smaller. Less heat will escape.

    The energy that is incoming still has to be radiated or convected away. For a new balance to be obtained, the surface would have to grow hotter. This would force air away from the surface and lower the local density. Notice that it would not change the pressure at all, just the density! It is not sufficient to talk about pressure, you MUST specify density. Notice also that any change in sea level temps is going to result in local density changes and thus subtly alter Aa-Ed.

    We see this result on Venus. Venus isn’t hotter just because it has 92 atmospheres of pressure, or because the atmosphere is 96 percent CO2. These are necessary but not sufficient causes. It’s hotter because it lacks evaporation, has no “window” to speak of, and has an Aa-Ed gap that is so inherently tight that only very high temperatures will open it up sufficiently. To get rid of a few hundred Watts of incoming sunlight, the surface has to blaze with 750 K and 16,000 W/m2 of outgoing radiation. More than 99 percent of that outgoing radiation comes straight back down; only a sliver can escape.

    I believe if we reduced the mass of the atmosphere on Venus by half, temps would fall from 750 K to around 630 K. So I agree in broad terms with Nikolov-Zeller. But it seems to me (again, not having read them very deeply as yet) that their theory lacks a specific mechanism to cause pressure to lead to higher temperatures. I suspect that this is the mechanism. Notice that it is a radiation mechanism (so we must congratulate Miskolczi on having proved one of his main points), and at the same time, it cannot be correctly modeled unless you pay close attention to vertical density shifts (which means we need to employ my ‘Pot Lid’ argument).

    I think that an alternate theory of climate is gradually emerging here. Neither I, nor Miskolczi, nor Nikolov-Zeller have the complete answer. But we are identifying issues that are not well addressed by the mainstream consensus, and there is some underlying agreement on where to look.

    Comments on this argument would be much appreciated. I also would like to direct readers to some further points about density and Miskolczi on my blog: declineeffect.com/?p=263

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