On Professor Gray’s Explanation of the Scientific Method

Written by Dr Jim Petch

Vincent Gray’s recent contribution on ‘The Scientific Method’ prompts me to respond with an extended set of points on Karl Popper’s ideas. My first article for PSI addressing Popper’s work is found here.Popper

It is refreshing to see reference to the work of Peter Medawar who seems to be neglected by today’s commentators on science including climate science. He has much to say of sound common sense and in my view climate scientists and their fellow travelers (on all sides) would do well to try to take from his writings something of his spirit and humanity.

It is good also to see emphasis on the lessons Karl Popper teaches us but again on Principia Scientific, important parts of his ideas are poorly presented and I feel it is important to keep making points of argument which at first sight may appear pedantic but which, in fact, are pivotal to a proper understanding of Popper’s philosophy and to a proper appreciation of how the empirical science should be conducted.

Vincent presents a set of diagrams that illustrate what he calls the ‘methods approved by Popper”. In fact Popper, to my knowledge, made no such approval and was most clear that for him there was no scientific method. He did prescribe the method of conjecture and refutation as the way to eliminate error.

Strangely the diagrams Vincent presents retain the inductivist error of going from observation to hypothesis and not the other way around as it should be with the deductivist Critical Rationalist approach of Popper.

The systems Vincent presents may, as he says, use a mixture of induction and deduction but if so Popper would surely have rejected them since he found no place at all for inductivist reasoning. Again as far as I know, the only diagram Popper gives us is his schema for conjecture and refutation in the sequence

P1 – TT – EE –P2 and so on and on.

This embodies an altogether different idea than the diagrams Vincent provides. Its focus is on the repeating cycle of problem situations, which arise from the testing of ideas against observation.

As regards Vincent’s comments on Climate Science, while I fully agree with his remarks about repeatability, I disagree that in this field no observation can be repeated’. If this were true then no observation anywhere at any time could be repeated, which is of course silly. Observation are intrinsically repeatable and in reality, within reasonable bounds, observations are repeated. The fact that there are differences of instruments etc etc does not negate the intrinsic repeatability of meteorological measurements (you cannot, of course, measure climate, but that’s a different story!!).

And it is not clear why a supposed lack of repeatability has anything to do with identification of trends. Two different issues with no real connection are conflated here.

There is also a logical non sequitur in that whether or not scientific conclusions based on observation alone are unreliable or not has nothing to do either with repeatability or with forming premature conclusions. That view, which I agree with, rests on quite different points of argument.

And again at this point Vincent slips on the induction banana skin. There is, if we accept Popper’s ideas, no criterion of validation, only a criterion of falsification. The point is that ideas should be tested critically, not validated, and those ideas retained which have withstood severe testing. A small point, you cannot test for falsifiability, only for falseness in ideas. Falsifiability is not a matter of testing but of logic.

And, as an aside, Planck’s idea are not validated in the inductivist sense but have withstood severe testing (for the time being).

And the question for us is not ‘can Climate change theory be validated?’ (that asks for inductive reasoning). But should be ‘how do we design tests that will show climate change theory to be wrong if it is?’ A quite different matter methodologically and in terms of the practicality of experimental design. 

Again, whether or not ideas/models are tested against past or future data is beside the point. The issues are their testability and the severity of the tests we subject them to.

——————

Dr Jim Petch was until late 2007 the head of the Distributed Learning Centre at the University of Manchester, when he retired. His focus of study is towards Critical Rationalism.

 

Tags: , , , , , , ,

Comments (43)

  • Avatar

    visiting physicist

    |

    [b]To all:[/b]

    I would suggest that the thread about greenhouse gases is much more applicable for this discussion. There are comments of mine from #80 onwards which say pretty much all I need to say in answer to your questions. If you choose not to try to understand what I have written, then please don’t engage me in discussion.

    [b]If you have genuine questions please write on that thread linked here …
    [/b]
    http://www.principia-scientific.org/by-definition-aren-t-all-gases-greenhouse-gases.html

  • Avatar

    visiting physicist

    |

    I have answered your question in various documents and comments, as well as in my book now being printed. Briefly, inter-molecular radiation plays a part in reducing the temperature gradient that corresponds to the thermodynamic state of greatest accessible entropy. On Earth it is reduced by about a third mostly by water vapour, on Venus it is reduced by a little less (due to carbon dioxide) and on Uranus by only about 5% in magnitude due to a sprinkling of methane in its (theoretical) 350Km high troposphere which is between 50Km and -300Km altitude.

  • Avatar

    Plchampness

    |

    I would regard an outcome of my experiment of 7c/km as an intermediate (indeterminate) result.

    The proper answer for a gravitational gradient is 9.8C/km. Isothermal is 0C/km.

    What would you accept as a definitive result?

  • Avatar

    visiting physicist

    |

    You can not just reduce the 33°C fiction to the 20°C.

    Greg, my reason for saying “at least 20 degrees” is that the calculation of the pivoting altitude gives something between 3Km and 4Km, rather than 5Km as claimed by the IPCC. So, for a temperature gradient of 7C/Km, that would be a temperature difference of 21 to 28 degrees. The exact magnitude doesn’t matter – the point being that there is indeed a difference which cannot be explained as being due to direct Solar radiation reaching the surface. You cannot prove your assertion that there is no difference at all.

  • Avatar

    visiting physicist

    |

    Greg has chickened out of answering the question about Venus because he can’t. Nor can anyone else. Greg doesn’t seem to realise that I have already pointed out that there is indeed a temperature difference of the order of 20 to 33 degrees between Earth’s surface temperature and its radiating temperature. The Sun could not achieve even 20 degrees of warming above the radiating temperature with direct radiation to the surface. As I also explained that surface temperature cannot be calculated using Stefan-Boltzmann Law because the latter only applies to black and grey bodies and is totally inapplicable for Earth’s surface. So I have answered all Greg’s questions, but he can’t even begin to explain Earth’s surface temperature, let alone those on Venus and Uranus, or the temperature in the core of the Moon, etc.

    Plchampness seems to have dropped the idea of doing an experiment which may well have confirmed the temperature gradient which is not “weak” but well known to be about 7C/Km on Earth. Roderich Graeff has already done over 800 such experiments this century and it would be highly improbable that virtually all of them showed a temperature gradient if no such gradient existed. He got his physics wrong in that he multiplied incorrectly by the degrees of freedom, but his experimental design was quite good.

    But apart from all that, temperature data on Uranus and Venus proves that what I am explaining is correct. You all just need to have open minds and read the explanation which is now being published in great detail in book form.

  • Avatar

    Plchampness

    |

    Tim, Doug, Greg.

    I think you mighty have missed this bit in Dt Petch’s article.
    [b]
    “‘how do we design tests that will show climate change theory to be wrong if it is?’”[/b]

    This argument can not be resolved by reasoning, of any nature, because the underlying physics is in dispute!

    Tim has undermined my proposed experiment by pointing out that the temperature gradient in the earth’s atmosphere is very weak. Therefore my proposed insulation (insulted plastic hot water pipe), would probably not be adequate.

    Can you propose an alternative experiment. I was thinking of some sort of centrifuge to increase the (proposed) gravitational effect.

  • Avatar

    Greg House

    |

    [quote name=”visiting physicist”]Greg please answer the question about how the required energy gets into the Venus surface to cause its temperature to rise by 5 degrees during its 4-month-long day.[/quote]

    No, Doug, this is not going to happen.

    Again, you explained what you considered a real 33°C difference in temperature by inventing “gravitationally induced temperature gradient”. Now you know that that 33°C difference is a fiction and there is no “additional temperature” on Earth. Hence there is no “gravitationally induced temperature gradient” on Earth. Hence there is no “gravitationally induced temperature gradient” at all, unless there are different types of gravities on different planets, of course: those that induce temperature gradient and those that do not. Which provides you with the splendid opportunity to establish another theory. Please, go ahead, I am looking forward to it.

  • Avatar

    visiting physicist

    |

    Greg please answer the question about how the required energy gets into the Venus surface to cause its temperature to rise by 5 degrees during its 4-month-long day. This is highly relevant for understanding what determines Earth’s surface temperature. If you can explain it then I will understand your point of view better. I have done so based on valid physics.

  • Avatar

    Greg House

    |

    [quote name=”visiting physicist”]Why do you and PSI members keep on trying to just modify the IPCC concept that radiation causes surface temperatures to be what they are?[/quote]

    Doug, please, do not distort my point.

  • Avatar

    visiting physicist

    |

    And, by the way, Greg, don’t you realise that the mechanism I have described (based on Kinetic Theory and the Second Law of Thermodynamics) applies to all planetary temperatures in their atmospheres, surfaces, crusts, mantles and cores? Why are you even talking about just the Earth’s surface? Even as the sun shines on the surface some of the energy is transferring into the crust and the lower atmosphere by conduction, and some liquids are cooling by evaporation. So it would need some radiative flux to provide this lost energy before the Sun could raise the temperature.

    It is the biggest blunder made by the climatologists that they think they can calculate what the surface temperatures of Earth, Venus, Uranus etc ought to be based solely on incident radiation. Because they didn’t get the right answer just using solar radiation, they invented an assumed heat transfer mechanism for back radiation so that they could add the back radiation flux to the solar flux and thus double it all and get somewhere nearer the right answer by incorrectly assuming the surface acted like a grey body (with >0.9 absorptivity) and was not losing any energy by non-radiative processes.

    Why do you and PSI members keep on trying to just modify the IPCC concept that radiation causes surface temperatures to be what they are? It is so blatantly obvious that the Venus surface temperature (over 730K) cannot be further increased by 5 degrees in 4 months by direct solar radiation or back radiation, now can it? Be sensible Greg and face reality!

  • Avatar

    Greg House

    |

    [quote name=”visiting physicist”]Now, if you don’t think there is at least, say, 20 degrees of additional temperature in Earth’s surface compared with its radiating temperature, then perhaps the difference on Venus will be sufficient to stump you.[/quote]

    Come on, Doug. You can not just reduce the 33°C fiction to the 20°C fiction and switch to “explaining” the second one by the same “gravitationally induced temperature gradient” fiction.

  • Avatar

    visiting physicist

    |

    You cannot apply the SBL to the internal interface between the Earth’s surface and its atmosphere because about two thirds of the energy that transfers from the surface to the atmosphere does so by way of non-radiative processes, according to the original NASA net energy diagrams. The SBL applies only to black and grey bodies which, by definition, only gain or lose thermal energy by radiation. In other words they have to be in space.

    Now, if you don’t think there is at least, say, 20 degrees of additional temperature in Earth’s surface compared with its radiating temperature, then perhaps the difference on Venus will be sufficient to stump you.

    [b]Where is your explanation as to how the solar energy gets down into the Venus surface and warms it by 5 degrees over the course of every 4-month-long Venus day? No one else has been able to answer this question.[/b]

  • Avatar

    Greg House

    |

    [quote name=”visiting physicist”]You haven’t read or understood my proof using kinetic theory and the Second Law of Thermodynamics.[/quote]

    Doug, by your “proof” you explained something that even does not exists, I mean this “33 degrees of warming” fiction.

    Now you should have a second look at the temperature on Earth and recognize that there is no room for any other “warming” on Earth than the one induced by the sunlight. No room for “greenhouse effect” and no room for “gravitationally induced temperature gradient”.

  • Avatar

    visiting physicist

    |

    You haven’t read or understood my proof using kinetic theory and the Second Law of Thermodynamics. A more comprehensive explanation (over 20 pages) has been accepted for publication soon.

    You have not been able to explain how and why the Venus surface rises in temperature by about 5 degrees during the 4 months of sunlight. Where does the energy come from and how does it get into the surface. When you can explain this observed fact by any other valid process I will be all ears.

  • Avatar

    Greg House

    |

    @#27

    Doug, you failed to prove the existence of “gravitationally induced temperature gradient”.

    There is gravity and there is temperature gradient, but you failed to prove the causality.

    As for your [i]”Direct solar radiation reaching Earth’s surface cannot cause the mean temperature to be of the order of 287K.”[/i], again, this is nonsense based on a wrong application of the SB equation, see the reference above.

  • Avatar

    visiting physicist

    |

    [b]To all:[/b]

    See Comment #80 [url=http://www.principia-scientific.org/by-definition-aren-t-all-gases-greenhouse-gases.html]here[/url].

  • Avatar

    visiting physicist

    |

    @ Greg. Firstly, the absolute zero (0K) scenario is a red herring, because no molecules move or collide, so the process whereby gravity sets up a gradient as molecules move in free flight between collisions does not exist at zero K.

    Now, regarding Uranus, yes you have calculated the radiating temperature of Uranus fairly accurately and of course I was aware of such. The TOA temperatures are just a little below that and most absorption and re-emission of Solar radiation takes place in the uppermost region of the atmosphere because of the methane layer there, and that region is close to 70K in temperature.

    But the gravitationally induced temperature gradient (which is a necessary corollary of the thermodynamic equilibrium state which the Second law of Thermodynamics says will evolve) has nothing to do with the radiating temperature.

    I suggest you read all my comments above so that perhaps you may be able to ask more appropriate questions. Or you can wait two or three weeks and then I’ll tell you where you can read a detailed explanation of more than 20 pages.

    Direct solar radiation reaching Earth’s surface cannot cause the mean temperature to be of the order of 287K. Likewise, it cannot cause the Venus surface to warm by 5 degrees to over 730K spread over each 4 month long Venus daytime. And as for Uranus, no significant solar radiation even reaches below its methane layer in the uppermost atmosphere. Are you saying there is no warming of the surfaces of these planets other than by direct solar radiation?

  • Avatar

    Greg House

    |

    [quote name=”visiting physicist”]If there were no gravitationally induced temperature gradient then we would not have that “33 degrees of warming” wrongly attributed to greenhouse gas back radiation.[/quote]

    Doug, there is no “33 degrees of warming”, this is a fiction created by warmists by wrongly applying the SB equation. We’ve had a nice discussion on that here recently: http://www.principia-scientific.org/by-definition-aren-t-all-gases-greenhouse-gases.html#comment-3447

  • Avatar

    Greg House

    |

    [quote name=”visiting physicist”]If you imagine the scenario of no background radiation in space and no energy generation by nuclear processes or whatever within the Earth, then everything would be at zero K.[/quote]

    …which means there is no gravitationally induced temperature gradient. Which means if there is somewhere temperature gradient in the atmosphere, it is not gravitationally induced. Simple logic.

    [quote name=”visiting physicist”]However, consider Uranus. It receives, let’s say, about 0.1% of the Solar radiation that Earth receives from the Sun. But in the course of the life of the planet, that has been quite sufficient to raise the Uranus core temperature to about 5,000K[/quote]

    Doug, according to the SB equation, 0.1% of the Solar radiation that Earth receives from the Sun induces maximum temperature of 70°K. Now, as a physicist you should know, that by storing 70°K somehow you can never achieve a higher temperature than 70°K, the same goes for any temperature value. If you put an atmosphere on the surface at 70°K, you will certainly get a temperature gradient, but only from this value down with increasing altitude, and never any value above 70°K.

    If it is warmer on the Uranus surface, it can only be due to the heat coming from underneath the surface.

  • Avatar

    visiting physicist

    |

    No – gravity is not producing a constant outflow of energy except on gaseous planets that are collapsing, like Jupiter. On Uranus gravity simply “traps” energy – rather like it traps water in a lake so that it doesn’t fly off into space as the earth rotates.

    If you imagine the scenario of no background radiation in space and no energy generation by nuclear processes or whatever within the Earth, then everything would be at zero K.

    However, consider Uranus. It receives, let’s say, about 0.1% of the Solar radiation that Earth receives from the Sun. But in the course of the life of the planet, that has been quite sufficient to raise the Uranus core temperature to about 5,000K even though it is colder than 60K at the top of the atmosphere where methane is absorbing most of the incident insolation. There is no need for any internally generated energy for such temperatures to exist, and there probably isn’t any on Uranus. All the thermal energy in the system has come from the Sun and been “trapped” by the gravitationally induced temperature gradient.

    If there were no gravitationally induced temperature gradient then we would not have that “33 degrees of warming” wrongly attributed to greenhouse gas back radiation.

  • Avatar

    Greg House

    |

    [quote name=”visiting physicist”]The gravitationally induced temperature gradient …[/quote]

    I wonder, Doug, what if we turn off the Sun and ignore the internal heating from the earth core? How high would be the [b]gravitationally induced[/b] surface temperature or the near to surface air temperature then? And how do you calculate that?

    I am asking, because this theory looks like creating energy out of nothing, if there is no input, but still some constant [b]gravitationally induced[/b] output from the warm surface.

  • Avatar

    visiting physicist

    |

    The gravitationally induced temperature gradient has [i][b]everything[/b][/i] to do with climate. It determines temperatures in atmospheres, planetary surfaces and sub-surface regions throughout the universe.

    Back radiation from radiating gases like carbon dioxide and water vapour does not cause planetary surfaces to become hotter. Water vapour cools Earth’s surface – the exact opposite of what the IPCC claim.

    You are totally incorrect in saying all atmospheres are heated from the bottom. On Uranus virtually all solar radiation is absorbed in the uppermost (methane) layer and from there the heat is able to transfer downwards, because the temperature gradient is the state of thermodynamic equilibrium and new energy disturbs that equilibrium. Thus new energy absorbed at the top of the atmospheres of Uranus and Venus warms the whole atmosphere and the surface. This happens to some extent on Earth too, because the Sun’s direct radiation could never raise the surface temperature to what is observed unless the temperature gradient were there supporting the minimum nightly temperatures.

  • Avatar

    Tim Folkerts

    |

    Time to wrap up this conversation since …
    1) it now has nothing to do with the top post
    2) these esoteric physics details are beyond the scope of what directly relates to climate (and are not going to be answered in a setting like this)
    3) EVEN IF the adiabatic lapse rate were the equilibrium condition, it would not matter! All atmospheres of planets (and moons that are large enough to have an atmosphere) have GHGs; all are heated from the bottom and cooled from the top; all would have a lapse rate whichever of us is right.

  • Avatar

    visiting physicist

    |

    Perhaps you need to read up on Kinetic Theory which Einstein and many others used successfully. No individual molecules travel a significant distance in any direction relative to the height of the columns of air that we are talking about. Gases do mix and have a tendency towards forming a homogeneous blend because of the random motion of molecules which change direction at every impact with another molecule. Until they do mix there will be various temperature gradients (based on the weighted mean specific heat at any location) but, most importantly, there cannot be any perpetual cyclic motion in the whole system of connected columns of various gases.

    Now, whilst not all molecules have exactly the same KE of course, it is not inaccurate to assume that the mean KE of all molecules a small mass of gas is proportional to the absolute (K)temperature. But I stress, the motion is random after each collision. It is quite possible that the molecule with more KE will go in a more downward direction and that with less go upwards after a collision. Your statement about those with the most KE going highest is totally incorrect, partly also because not all motion is exactly vertically upwards.

    Suppose two molecules with the same KE collide. Surely it is obvious that they don’t both then travel in a horizontal plane – one may well go up and the other down.

    In a horizontal plane there is a propensity towards homogeneous KE. The Second Law is more general because it tells us that in any plane, including a vertical one in a gravitational field, there is a propensity towards a state of thermodynamic equilibrium with maximum accessible entropy. Such an ideal state would be achieved if there are no unbalanced energy potentials. This happens if the sum of KE and gravitational PE for all molecules were the same. In such a state, since only the KE component determines temperature (not the PE component) there must therefor be a temperature gradient.

  • Avatar

    visiting physicist

    |

    Firstly, answer how and why the Venus surface and all its troposphere warm by 5 degrees gradually over the course of 4 months in its daytime. Where does the energy come from and how does it get into the surface?

    Then show me your source of such information pertaining to the alleged energy flow from the solid core of Uranus.

    As I said in an earlier comment, there is no evidence of any internal energy generation on Uranus resulting in any net outflow at TOA, and such a weak flow that you claim, even if it did exist, could not possibly be all that a 5,000K temperature would cause to transfer from the surface of the solid core to the atmosphere by both radiation and conduction. Why should the atmosphere not cool faster than the temperature gradient “allows” if, as you think, the equilibrium state is isothermal? It does so locally near Earth’s surface after a hot sunny morning. Remember, the night side of Venus cools 5 degrees in 4 months.

    No instrument has measured flux at the surface of the Uranus core about 20,000Km below its TOA. Secondly there is virtually no detectable difference in the inward Solar radiation and the outward radiation at TOA. What you have quoted is roughly the outward flux at TOA virtually all of which comes from the relatively thin methane layer which absorbs and re-emits virtually all of the weak Solar radiation.

    Try working out how much flux would be radiated out of a surface at 5,000K if the atmosphere were free to cool off. Where is your balancing energy input? I can explain it because solar energy has been trapped by gravity because of the gravitationally induced temperature gradient. Solar energy absorbed at the top of the Uranus atmosphere has spread downwards and accumulated over the life of the planet for no other reason than the fact that gravity maintains a thermodynamic equilibrium state which must have a temperature gradient that is a function of the acceleration due to gravity.

    And why is the core of our Moon far hooter than the surface ever gets to be? Same reason – solar energy absorbed at the surface travels slowly towards the hotter core following the gravitationally induced temperature gradient, just as we can observe in actual borehole measurements in the outer 10Km or so of Earth’s crust.

  • Avatar

    Tim Folkerts

    |

    [i]”You cannot explain the -g/Cp gradient on Uranus if you assume a tendency towards an isothermal state. “[/i]

    Yes, I can. Even thought the heat flow up from the interior is much smaller for Uranus than for the other gas giants, it is estimated at 0.042 W/m^2. While this is tiny, is is not zero. While this it tiny, is is still more than can be conducted up through a gas (do the math). Hence this small heat flow is STILL enough to set up (very weak) convection. Uranus will have a typical sort of lapse rate — not because that is the “equilibrium” condition, but because that is the proper NON–equilibrium solution to these conditions where heat flow sets up a temperature gradient.

  • Avatar

    Tim Folkerts

    |

    “Your discussion that claims that molecules that rise don’t lose kinetic energy and thus cool is incorrect. “

    I didn’t discuss that per se .. but that is ALSO a good way to show that the gas will indeed be isothermal.

    You are partly correct — any given molecule that rises will lose KE on the way up. But (and this is a big “but”) the molecules that get to the higher levels are those that had higher KE to start with. The slowest molecules will be stopped by gravity before they reach the higher level.

    So for example, out of 1000 molecules on their way up, maybe only 100 have enough KE to start with to reach some particular altitude. Those 100 molecules will indeed have lost KE on the way up. But they are the molecules that started in the “higher energy tail” of the MB distribution. It turns out (not coincidentally) that the KE they lose on they way up is exactly enough to lower the KE from “way above average” to “average”.

    [i]”WUWT ran an article …”[/i] and the consensus was “isothermal” not “adiabatic lapse rate”. This is not something that we will answer in a setting like this … it would take considerably more in-depth discussion and calculation.

    “Thermodynamic equilibrium will not be achieved until the gases have mixed to form a homogeneous gas “
    That is a very extreme view of what it means to come to equilibrium. It is certainly one way to go, but not what most people mean. In this view, a block of copper at one temperature and a block of zinc will never come to equilibrium if you push them together — at least not for billions of years until the atoms of copper and zinc have diffused to for a uniform block of brass. Basically NOTHING will ever meet your criteron, including your own systems. This is a specious argument.

  • Avatar

    visiting physicist

    |

    If the two columns are connected then they become a single closed system. Thermodynamic equilibrium will not be achieved until the gases have mixed to form a homogeneous gas and the gradient will then be the same in each, based on [i]-g/Cp[/i] where Cp is the weighted mean specific heat. (By the way, specific heat is not the same as heat capacity.) You can’t have your cake and eat it – you want to connect the two systems and yet keep the gases separate. That’s not physics.

    WUWT ran an article also trying to prove Loschmidt wrong with a wire from the bottom to the top of a cylinder of gas. But the wire also becomes a part of the system. They thought (incorrectly) that there would be perpetual motion. But they overlooked the fact (as Loschmidt had stated) that solids also exhibit a temperature gradient. The equilibrium state will be stable without any perpetual circulation no matter what sort of similar thought experiment you postulate.

    Your discussion that claims that molecules that rise don’t lose kinetic energy and thus cool is incorrect. Suppose you start with a sealed insulated cylinder divided in three using removable partitions. Pump gas into the middle section and create vacuums in the top and bottom sections. Remove the partitions and some molecules move to the top section and some to the bottom section. Each movement in free flight must have an interchange between KE and gravitational PE and those in the top section end up with less KE and are thus cooler. Vice versa for the bottom section.

    Isothermal conditions cannot be in thermodynamic equilibrium because there is more gravitational PE per molecule in the higher regions. Some molecules will fall more than they rise as a result. You cannot explain the [i]-g/Cp [/i]gradient on Uranus if you assume a tendency towards an isothermal state. Read the info above about Uranus.

    Now you still have a lot of questions to answer about Uranus, Venus, the Moon etc. Before you do I suggest you study and try to understand all the comments I have written above. Anything you claim to the contrary I will be able to rebut here in public.

  • Avatar

    Tim Folkerts

    |

    [b]To other readers:[/b] Unfortunately there is not simply one statement that epitomizes visitingphysicist’s (VP) lack of understanding.

    He shows a couple of the classic challenges associated with effective internet discussions of the science behind global warming.
    1) A moderate amount of knowledge that he thinks is expert knowledge.
    2) A predisposition to one conclusion that clouds judgement.
    [And these problems canimpact people no matter what predisposition they have.]

    [b]A few specific cases…[/b]
    [i]”I didn’t write “thermal equilibrium” – I wrote “thermodynamic equilibrium” which is quite a different thing”[/i]
    Thermal equilibrium is a subset of thermodynamic equilibrium. Hence VP’s claim of thermodynamics equilibrium necessarily includes a claim of thermal equilibrium.

    [i]”Consider the temperature gradient between the Moon’s surface and the far hotter core of the Moon. When the Sun shines on the surface there is a movement of thermal energy up that gradient … ” [/i]
    Of course, VP didn’t mean that last sentence, since that would be a clear violation of the 2nd Law. Heat ALWAYS moves DOWN thermal gradients.

    [i]”Regarding your belief that planets (and also our Moon perhaps you think) formed with hot cores and have not had time to cool, where are your calculations?” [/i]
    Seriously? This is basic astronomy. And once again, the cores are HOTTER than the surface of the sun, so the sun could not have heated the cores.

    Do the math. As a rough estimate, the earth is 6e24 kg and the specific heat of rock is 1e3 J/kg*K, so to cool the whole earth by 1 K, we need to shed 6e27 J of energy. The surface area is 5e14 m^2, so we need to lose ~ 1e13 J/m^2. If we estimate the earth conducts 1 W/m^2 of heat up through the rock, then it will take 1e13 second to cool by 1 K, or 0.3 million years. Cooling 1000 K would take 0.3 billion years. Early on, the earth would have lost energy faster; presently estimates are that it loses energy much slower. (Plus there is nuclear energy that continues to slow the cooling of the interior.

    A simple back-of-the-envelop calculation supports cooling times on the order of a billion years. Textbooks support this idea. The only support that this is a “glaring error” is your “proof by bold assertion”.

    [i]”The Second Law of Thermodynamics applies to individual closed systems.”[/i]
    The 2nd Law applies to sets of systems, too. Put an ice cube in glass of water. The second Law applies to the combination of the two systems; the ice melts & warms up gaining entropy while the water cools down and loses entropy (with the net change being positive, of course). Similarly, if we have two columns of gases that in thermal contact, the pair of systems will evolve until they have reached thermal equilibrium and have maximized entropy of the pair of systems.

  • Avatar

    Tim Folkerts

    |

    visitingphysicist (VP) says [i]”And no, you cannot produce a perpetual motion machine based on such temperature gradients any more than you could with pipes at different angles between a higher and lower reservoir of water.”[/i]
    This is the core of the discussion. Let me clarify, since clearly VP didn’t understand the brief version (and so others might not either).

    Imagine there are two sealed columns of different gases, one with Cp = 1000J/kg*K (similar to air) and one with Cp = 2000J/kg*K (similar to ammonia). The bottoms of the two columns are at the same temperature – call it 300 K for the sake of argument (perhaps they are both in the same lake, or just curved around so they touch each other; it really doesn’t matter) Above this point, the columns are insulated. If we let the systems come to thermodynamic equilibrium, what will the temperatures be 10 km up? If VP is right, the first column will be -(9.8m/s^2)/(1000J/kg*K)*(10000m) = – 98 K cooler = 202 K. Similarly the second column will be -49K cooler =251 K. Now at the top we can remove a little insulation and rejoin the two columns. Heat will flow from one side to the other; we could add a heat engine and extract work. The columns would continue to “move toward VP’s equilibrium” with one at 251 K and one at 202 K. We could keep running the engine for ever off this temperature gradient, with no input of work.

    Since VP correctly concluded that no perpetual motion machines exists, then the only conclusion is that the equilibrium condition is NOT a temperature gradient.

    [i]”If you were to have KE=constant then gravitational PE would still vary with height, so there is extra energy per molecule at the top.”[/i]
    For the sake of argument, suppose the column happened to be isothermal to start with. To have a temperature gradient develop as VP thinks would happen, the gas at the bottom would warm [i]and expand[/i]. if the gas expanded at the bottom, the whole column above it would rise = more potential energy throughout the column = more PE per molecule. We would have to find a way to add energy to raise the center of mass. This would require the average temperature to spontaneously cool. Things don’t spontaneously rise and cool; they spontaneously fall and warm.

    ***********************************

    The adiabatic lapse rate is NOT the equilibrium condition! Isothermal is.

    The very name “adiabatic” is critical. This lapse rate ONLY works if conduction is prevented (each parcel is adiabatically isolated from the surrounding parcels, so that heat cannot flow to allow the system to move toward true equilibrium.

  • Avatar

    visiting physicist

    |

    [b]To other readers:[/b] If there is one statement which epitomises warmist Tim Folkert’s lack of understanding of thermodynamics it is this one where he wrote: [i]”Columns of different gases would thus be different temperatures at the top, even though your argument says they would be in equilibrium. With different gases at the same altitude at different temperatures, we could extract work with YOUR system with a simple heat engine.”
    [/i]

    The Second Law of Thermodynamics applies to individual closed systems. His separate columns of gas are each separate closed systems because he implies that the gases cannot mix. Yes, each would be in a state of thermodynamic equilibrium when, over the full height of the column, the sum of kinetic energy and gravitational potential energy of all very small bodies of gas is homogeneous. When (PE+KE)=constant we do of course have close to the -g/Cp temperature gradient which is observed.

    It is because (PE+KE)=constant that we have no unbalanced energy potentials. If you were to have KE=constant then gravitational PE would still vary with height, so there is extra energy per molecule at the top. The Second Law of Thermodynamics would not be satisfied.

    Another glaring error is his claim that all planets are cooling off and have not had time to cool down yet. That is utter nonsense, as I have explained in comments above about Uranus and Venus. But of course, because that is not the case, Tim cannot explain how the required energy originally absorbed near the TOA on these planets gets into the far hotter surface, because it certainly is not by back radiation or direct solar radiation as there is nowhere near enough of either.

    And finally, Tim, why does actual temperature data on Earth confirm that moist regions with higher rainfall have lower mean daily maximum and minimum temperatures than similar but drier regions? Does the greenhouse conjecture “explain” that greenhouse gases like water vapour are supposedly warming the surface? Don’t they say that these gases cause the very temperature gradient we are talking about (rather than gravity doing so) and isn’t that supposed to prop up the surface temperature by 33 degrees? Ooops – water vapour reduces the temperature gradient because the moist rate is not as steep, now is it? Please explain!

  • Avatar

    visiting physicist

    |

    The following information about Uranus will help you understand why you cannot explain its temperature gradient as being due to a surface cooling off:

    “What is most surprising about Uranus’ interior and one of the most distniguishing features with respect to the other gas giants is that it does not emit more energy than it receives from the Sun. Considering that even Neptune, which is very similar in size to Uranus, produces approximately 2.6 times the amount of heat that it receives from the Sun, scientists are very intrigued by the low heat that Uranus generates. “

    Source: http://www.planetsofthesolarsystem.net/uranus.html

    Temperature data

    “The Uranian atmosphere can be divided into three main layers: the troposphere, between altitudes of −300[a] and 50 km “

    “The temperature falls from about 320 K at the base of the troposphere at −300 km to 53 K at 50 km.[2][17”

    Source: http://en.wikipedia.org/wiki/Atmosphere_of_Uranus

    “Uranus has a core of only 5,000 K, while Jupiter’s core is 30,000 K.

    Read more: http://www.universetoday.com/19282/temperature-of-uranus/#ixzz2rxsRtXMv

    Source: http://www.universetoday.com/19282/temperature-of-uranus/

  • Avatar

    visiting physicist

    |

    (continued)

    Regarding your belief that planets (and also our Moon perhaps you think) formed with hot cores and have not had time to cool, where are your calculations?

    The Venus surface cools by about 5 degrees during the 4 month Venus night. If there were no radiating Sun to heat it back up the next day, it could easily have cooled right down – that is, but for the fact that gravity traps its thermal energy.

  • Avatar

    visiting physicist

    |

    @ Tim Folkerts

    I didn’t write “thermal equilibrium” – I wrote “thermodynamic equilibrium” which is quite a different thing and which will evolve in accordance with the Second Law of Thermodynamics. It is a state with no unbalanced energy potentials and thus is a state of maximum accessible entropy. If you don’t understand this physics then I suggest you don’t write about matters that may be out of your depth, because you only serve to continue confusing the public, as weather folk and the IPCC have been doing since the 1980’s.

    A lack of heat flow does not mean temperatures are all equal in a gravitational field. Consider the temperature gradient between the Moon’s surface and the far hotter core of the Moon. When the Sun shines on the surface there is a movement of thermal energy up that gradient, and vice versa where the surface is in darkness. If I were wrong then the core of the Moon would be far colder than its surface, and so too would Earth’s core.

    And no, you cannot produce a perpetual motion machine based on such temperature gradients any more than you could with pipes at different angles between a higher and lower reservoir of water.

    PSI members have a lot to learn in this realm, but they continue to make no effort to understand thermodynamic equilibrium, entropy and energy potentials. This leaves PSI with no explanation of observed temperature data through the Solar System. When you all can explain the energy budget on Uranus, or under the Moon’s surface, or on Venus get back to me.

  • Avatar

    Tim Folkerts

    |

    PS. The “equilibrium atmospheric temperature gradient” is in many ways a moot poor.

    * ALL atmospheres have energy input at the bottom (geothermal and/or solar”).
    * ALL atmospheres lose energy from the top (since all have at least some gases that emit thermal IR to space).
    * ALL atmospheres have a heat flow upward. Hence the atmospheres might be close to “steady-state” but they are never close to “equilibrium”.
    * ALL planetary atmosphere will have a temperature gradient close to their appropriate adiabatic lapse rate.

  • Avatar

    Tim Folkerts

    |

    Visiting physicist makes the rather perplexing statement [i]”you simply cannot have thermodynamic equilibrium with isothermal conditions”[/i].

    Quite the opposite. Thermal equilibrium means that all heat flow has ceased, which necessarily means that the temperatures are constant. This is pretty much the definition of thermal equilibrium — see also the Zeroth Law of Thermodynamics.

    [i]”Such a state is not isothermal in a vertical column subjected to gravity “[/i]
    There have been extensive discussions of this, and in the end, the conclusion has been that the column should be isothermal even in a gravitational field.

    [i]”Hence work could be done … “[/i]
    Perhaps the simplest argument is that there are different lapse rates for different gases (since they have different heat capacities). Columns of different gases would thus be different temperatures at the top, even though your argument says they would be in equilibrium. With different gases at the same altitude at different temperatures, we could extract work with YOUR system with a simple heat engine. This engine would run indefinitely on the “equilibrium temperature difference” = perpetual motion = violation of the 2nd Law.

    [i]”I ask you also to explain the temperatures on the surface of the solid core of Uranus (55% of Earth’s mass) where it is thousands of degrees.”[/i]
    I already answered this. All planets form with hot cores (from the energy of in-falling material and nuclear decay). Uranus (just like the earth) still has a hot core because it simply has not had time to cool yet. For the earth, the outward geothermal energy flow is typically estimated on the order of 0.1 W/m^2 and it takes a looooong time to cool something the size of the earth or Uranus when the heat loss upward through the rocks is less than 1 W/m^2.

  • Avatar

    visiting physicist

    |

    If anyone thinks the Venus surface is (instantaneously) heated by any form of direct radiation then I suggest you do the sums. It would need over 16,000W/m^2 of incident flux coming from a source that is hotter than the surface itself (~730K) because radiation only ever transfers thermal energy from hot to cold. All the solar radiation reaching TOA (even before reflection from the Venus clouds) is less than the required amount. What actually reaches the surface is less than 20W/m^2. How could any back radiation somehow multiply that energy up to 16,000W/m^2? The energy simply isn’t there at any given moment. Yet the surface (and the whole troposphere) do warm gradually by about 5 degrees over the course of the 4-month long Venus day, regaining about the same amount of thermal energy that they lost during the night. How is that thermal energy getting into the surface? The answer was in the removed PROM paper on Planetary surface temperatures.

  • Avatar

    visiting physicist

    |

    @ Tim Folkerts

    What you say is the “intuitive” concept that climatologists fell for with their limited knowledge and even more limited understanding of physics. But it is not correct. I ask you also to explain the temperatures on the surface of the solid core of Uranus (55% of Earth’s mass) where it is thousands of degrees. Such temperatures have nothing to do with any direct Solar radiation reaching such a surface because there isn’t any. Yet there must be a supply of new energy each Uranus “day” (or Venus day) to balance the loss of energy at night on these planets. Such energy gets there by non-radiative processes in a way which PSI members continue to disregard, even though they have no other valid physics to explain all known temperature data in the Solar system. To explain a temperature you have to be able to explain the energy flows which maintain that temperature – that’s basic thermodynamics.

  • Avatar

    visiting physicist

    |

    @ Plchampness

    The “dispute” was resolved in the paper on Planetary Surface temperatures which was removed from the PROM menu, but was a very sound document. No, you simply cannot have thermodynamic equilibrium with isothermal conditions because the Second law of Thermodynamics says that a state of maximum accessible entropy will evolve. Such a state is not isothermal in a vertical column subjected to gravity because there would be unbalanced energy potentials due to the additional gravitational potential energy at the top. Hence work could be done and so entropy would not have been at a maximum. Furthermore, you need to explain how the energy actually gets down to the Venus or Uranus surface because it is certainly not getting there from direct solar radiation. Try explaining Uranus temperatures at its surface which is about 20,000Km below its TOA.

  • Avatar

    Plchampness

    |

    Thanks Tim,

    If the insulation requirements are as extreme as you say, that would,undermine the experiment. I do not have access to insulation which can impede a few miliwatts per sq m.

    My experiment was designed to differentiate between 2 views
    1. The atmospheric (environmental) lapse rate is caused by gravity, or

    2. The lapse rate is not cause by gravity.

    If an actual experiment cannot work, we are back to thought experiments, which are inherently unsatisfactory.

    I agree with you about convection. I have sat around gliding airfields on many a day waiting for convection to start. Convection starts when the temperature profile reaches the adiabatic lapse rate and not before.

  • Avatar

    Tim Folkerts

    |

    [quote]”The idea is that the atmospheric temperature gradient is created by gravity. … the GHGE is not required to explain the surface temperature.”[/quote]

    That is slightly turned around. Temperature gradients are related to heat frlow. Whenever there is heat flow though a materail, there must be a temperature gradient. Since the atmosphere is heated at the bottom (by sunlight) and cooled at the top (by IR radiation from GHGs & clouds), there will be a heat flow and a temperature gradient.

    Convection limits the temperature gradient in the air so that the gradient cannot get much above the adiabatic lapse rate of ~ 7 K/km (depending on humidity). If the temperature gradient tries to get larger than this, convection starts. Since the lapse rate depends on the strength of gravity (and the specific heat of the air), gravity is involved in setting the lapse rate. So gravity helps [i]limit [/i] the lapse rate, but gravity does not [i]cause [/i] the lapse rate.

    [quote]”My proposal is to create a tall insulated air column in a vertical pipe. “[/quote]
    I think you will find this experiment more challenging that you think. I did the calculations once. As I recall, the heat flow required to set up a thermal gradient of 10 K/km in air is a fraction of a milliwatt per square meter. That means your insulated pipe cannot allow even milliwatts of heat through the pipe or the effect you are looking for will be swamped by conduction through the walls.

  • Avatar

    Plchampness

    |

    I can understand some of that! And I agree with this statement: [i]”And the question for us is not ‘can Climate change theory be validated?’ (that asks for inductive reasoning). But should be ‘how do we design tests that will show climate change theory to be wrong if it is?’”[/i]

    Also to Visiting Physiscist above.
    The simple observation that the atmosphere of Venus has a thermal gradient has been proposed as proof against the GHGE by both Joseph Postma and Doug Cotton.

    The idea is that the atmospheric temperature gradient is created by gravity. Combine that with a radiation surface located in the upper atmosphere, approximately at the top of the troposphere. Then the sums all work out. Solar energy in equals Earth radiation out. The surface is hotter that the top of atmosphere (TOA) by the required amount and the GHGE is not required to explain the surface temperature.

    [b]However[/b], there is an alternative view, put by Dr Rob Brown, which is that the atmosphere (at equilibrium) would be isothermal from bottom to top. The atmosphere however is not in equilibrium (according to Brown). It is heated at the bottom by the surface which is warmed by back radiation (GHGE). The atmospheric temperature gradient (lapse rate ) is not caused by gravity but represents a thermal gradient between a heat source (surface) and a sink (outer space).

    To resolve this dispute I propose a simple experiment. The observation of planetary atmospheres is not adequate because there are confounding factors. A simplified and controlled experiment is required.

    My proposal is to create a tall insulated air column in a vertical pipe. Insulated plastic hot water pipe would do. Thermometers at the top and the bottom and compare temperatures. Insulated pipe is required so that outside atmospheric conditions do not impinge( eg temperature inversions, hot winds etc).

    The apparatus is not too expensive (prelim estimate $5-10,000) Not much by the standards of high energy physics. I have identified a possible site ( a disused Omega radio tower) which is 430m high. A temperature difference of about 4C is expected under the gravity hypothesis and 0C according to Brown. That should be sufficient to be conclusive.

  • Avatar

    visiting physicist

    |

    It is very easy to prove the concept of radiative forcing (fundamental to the GH conjecture) to be wrong by just using data measured on Venus. Even all the Solar radiation reaching TOA would be less than a fifth of the 16,000W/m^2 that would be required to heat its surface to around 730K.

    Any hypothesis should in my view start from a sound theoretical basis. When it comes to atmospheric physics we must start at the molecular level and come to an understanding that the state of thermodynamic equilibrium in a gravitational field must be a state in which there is a temperature gradient. We note that such is indeed observed on all planets. We then deduce that energy can move along that gradient, even towards the hotter surface. We then observe that this is the only possible way that planetary atmospheric and surface temperatures are being maintained at observed levels. Voila! We have the new (and correct) paradigm that explains all known temperature data in our Solar System.

Comments are closed