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Has the greenhouse effect been falsified?

What the science says...

Select a level... Basic Intermediate

The greenhouse effect is standard physics and confirmed by observations.

Climate Myth...

Greenhouse effect has been falsified
 

"[T]he influence of so-called greenhouse gases on near-surface temperature - is not yet absolutely proven. In other words, there is as yet no incontrovertible proof either of the greenhouse effect, or its connection with alleged global warming.

 

This is no surprise, because in fact there is no such thing as the greenhouse effect: it is an impossibility.  The statement that so-called greenhouse gases, especially CO2, contribute to near-surface atmospheric warming is in glaring contradiction to well-known physical laws relating to gas and vapour, as well as to general caloric theory.' (Heinz Thieme)

 

Some climate change skeptics dispute the so-called ‘greenhouse effect’, which keeps the surface temperature of the Earth approximately 33 degrees C warmer than it would be if there were no greenhouse gases in the atmosphere. In other words, without the greenhouse effect, the Earth would be largely uninhabitable.

How do we know for sure this effect is real? The principle is demonstrated through basic physics, because a bare rock orbiting the sun at the distance of the Earth should be far colder than the Earth actually is. The explanation for this observation was based on the work of John Tyndall, who discovered in 1859 that several gases, including carbon dioxide and water vapour, could trap heat. This was the first evidence for what we know now as greenhouse gases. Then, towards the end of the same century, a Swedish scientist named Svante Arrhenius proved the relationship between greenhouse gas concentrations and surface temperatures.

Empirical Evidence for the Greenhouse Effect

We only have to look to our moon for evidence of what the Earth might be like without an atmosphere that sustained the greenhouse effect. While the moon’s surface reaches 130 degrees C in direct sunlight at the equator (266 degrees F), when the sun ‘goes down’ on the moon, the temperature drops almost immediately, and plunges in several hours down to minus 110 degrees C (-166F).

Since the moon is virtually the same distance from the sun as we are, it is reasonable to ask why at night the Earth doesn’t get as cold as the moon. The answer is that, unlike the Earth, the moon has no water vapour or other greenhouse gases, because of course it has no atmosphere at all. Without our protective atmosphere and the greenhouse effect, the Earth would be as barren as our lifeless moon; without the heat trapped overnight in the atmosphere (and in the ground and oceans) our nights would be so cold that few plants or animals could survive even a single one.

The most conclusive evidence for the greenhouse effect – and the role CO2 plays – can be seen in data from the surface and from satellites. By comparing the Sun’s heat reaching the Earth with the heat leaving it, we can see that less long-wave radiation (heat) is leaving than arriving (and since the 1970s, that less and less radiation is leaving the Earth, as CO2 and equivalents build up). Since all radiation is measured by its wavelength, we can also see that the frequencies being trapped in the atmosphere are the same frequencies absorbed by greenhouse gases.

Disputing that the greenhouse effect is real is to attempt to discredit centuries of science, laws of physics and direct observation. Without the greenhouse effect, we would not even be here to argue about it.

Basic rebuttal written by GPWayne

Last updated on 1 August 2013 by gpwayne. View Archives

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Comments

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Comments 51 to 81 out of 81:

  1. Berényi Péter, in your comments about Venus, I think you may be neglecting Venus's albedo.
  2. Will writes: Thermal radiation is heat. Vibrating matter. Gas molecules are vibrating matter. They cannot pass through solid glass. You are confusing matter with energy. It is the energy which passes through the glass not the vibrating molecules which cause heat.

    In the vacuum of space full spectrum EMR produces no thermal radiation, heat.


    This is just absolute rubbish. Sorry, but there's no better way to put it.

    Thermal infrared radiation is merely a subset of the electromagnetic spectrum at wavelengths from around 3 to 1000 micrometers. The label "thermal" comes from the fact that this is the range in which the peak emittance occurs from objects at normal earth-surface temperatures.

    This is important because thermal infrared radiation is the only significant mechanism by which the Earth loses heat to space. If your claims were correct and longwave infrared radiation were unable to propagate through a vacuum, the Earth would rapidly heat up to the point where the oceans boiled away.

    Your willingness to write articles dismissing the greenhouse effect and accusing scientists of "fraud" when you don't understand even the most basic relevant physics is frankly shocking. It's far and away the best demonstration of the Dunning-Kruger Effect that I've seen in a long time.
  3. I'm glad to see people talking about simple experiments that attempt to illustrate the infrared absorptance of CO2. But there are two larger points in danger of being neglected here:

    (1) There is a very extensive literature on laboratory measurements of the spectral properties of CO2.

    (2) It's not really possible to completely replicate the real-world greenhouse effect in the lab. Part of the physical process involves an increase in the effective radiating height of the earth's atmosphere, something most labs aren't really set up to simulate. But there are many scientific processes that are similarly unsuited for laboratory replication -- plate tectonics is a great example. The fact that we're logistically incapable of recreating plate tectonics in a laboratory doesn't in any way invalidate it as a scientific theory.

    Like plate tectonics, we're able to make predictions based on the theories involved in anthropogenic global warming, and verify those predictions using observations. Some of those observations can be made under controlled conditions in the lab, but others can only be done in the real world environment. That's perfectly OK.
  4. Will at 03:30 AM on 26 August, 2010

    I think we all need to understand what we mean by “atmosphere” and “heating” at these altitudes and appreciate what is meant by “bulge” and temperature profiles. We are talking about Solar UV radiation “heating” the rarified atmosphere between around 100 and 200km up (and also geomagnetic interactions). The temporarily increased kinetic energy allows (on average) more molecules to move “upwards” away from the effect of gravity, thus leading to a redistribution of density, and an increased density above a few hundred km up. This variation in density of atmospheric gases at low earth satellite orbit heights (around 300km), or so called “diurnal bulge” caused periodic variations in drag which were investigated in the early satellite era. For some historical context see Moe 1977. In terms of temperature, we are referring to the kinetic energy of atoms or molecules, rather than temperature in the sense that most people understand. Figure 1 in Johnson 1967 shows typical “temperature” variations (night time minimum sunspot cycle of around 430 degrees C to daytime maximum sunspot cycle of around 1530 degrees C) associated with the “bulge”. A more detailed graphic, from here,



    shows your “top down heating” suggestion has a rather obvious problem at around the (arbitrary) Thermosphere/Mesosphere boundary around 90km up (approx -90 degrees C), and again towards the lower Stratososphere.

    More independent measurement based evidence against your suggestion is that daytime temperatures do not measurably rise in periods of intense radio and magnetic solar activity when the “bulge” and “heating” can increase dramatically. Average UV activity has also tracked overall solar activity over recent decades of direct measurement (ie small average decline).
  5. #52 Ned at 19:00 PM on 26 August, 2010
    you may be neglecting Venus's albedo

    I do. As I'm also neglecting the probable huge increase in Earth's albedo due to more clouds if it were put on a Cytherean orbit and also the increase in thermal IR opacity due to the same warm high clouds. The usual practice to ignore changes to albedo when discussing the greenhouse effect is admittedly a silly one. Like Earth with neither an atmosphere nor a hydrosphere but still retaining its present day albedo of 0.3 somehow, making its equilibrium temperature -18°C and comparing it to the actual average surface temperature of +15°C, calling the difference (33°C) the "greenhouse effect".

    As an exercise, calculate average surface temperature of a perfect blackbody "Earth" with no atmosphere at all for two cases.
    1. it's made of a perfect heat conductor material (uniform heat distribution along the surface is attained instantaneously)
    2. or it is made of a perfect heat insulator (each point on its surface is in radiative equilibrium, independent of its surroundings)
    There is neither greenhouse nor albedo effect in these cases, still, the difference in average equilibrium temperature is huge. You can also play with different heat capacities from zero up to very high values and see what happens.
  6. Berényi Péter @46

    "That is, if a gas does not absorb thermal radiation (like nitrogen) it can't get rid of heat by radiation either."

    Really?

    So 79% of the atmosphere is cooled by what process? Does the majority of the atmospheric mass have to transfer its energy through a bottle neck of 0.0385% CO2 in order to radiate to space?

    Or is their a secret mechanism that only clever people know about?

    Of course nitrogen emits radiation, at light speed. Therefore it must also absorb at the same rate or become frozen.
  7. Berényi Péter, it was your choice to move the Earth to Venus's orbit and make a quantitative prediction ("5 C") of the magnitude of the increase in temperature associated with the greenhouse effect.

    That prediction ignored the fact that Venus's albedo is much higher than Earth's. All else being equal, if you put Earth and Venus at the same distance from the sun and gave them the same albedo, Earth would be much colder due to the lower concentration of greenhouse gases in its atmosphere.

    If you now want to say "Well, there are all these other complications" that's fine -- I agree completely -- but let's note for the record that your initial remarks were just plain wrong.

    There doesn't seem to be an article on this site specifically about the greenhouse effect on Venus; perhaps that would be a good subject for a post some day. In the mean time, I'd refer anyone who's interested in that subject to:

    * Goddard’s World by Chris Colose

    * Venusian Mysteries and Venusian Mysteries – Part Two over at Science of Doom.
  8. Will writes: Of course nitrogen emits radiation, at light speed. Therefore it must also absorb at the same rate or become frozen.

    OK. At what wavelengths does nitrogen absorb and emit radiation?

    Berényi Péter provided a nice illustration of the absorption bands for other gases. Can you please give us a link to something that shows the equivalent spectrum for nitrogen? Thanks.

  9. Peter Hogarth @55

    The problem lies in the lack of understand of the fact that the atmosphere both radiates and insulates at the same time. This is the cause of the temperature gradient inversion profile of which of course your graph represent averaged figures day/night winter/summer.

    The temperature gradient inversions are caused by the fact that as the atmosphere thins it looses more energy via radiation, yet at the same time it still has an insulating effect. You have to consider this effect of insulation and radiation as three dimensional while at the same time incoming EMR is heating top-down unidirectional.

    Air is a top insulator and also a top radiator. The gradient inversions are caused by the imbalance between insulation, radiation and top-down heating.

    Claiming that the atmosphere is very thin at such high "Thermosphere" altitudes and therefore temperature is not relevant, is simply viewing this situation backwards. The bulge would not exist in the first place were it not for incoming EMR causing massive violent top-down atmospheric heating.
  10. (sorry, #57 was a mistake, I hit the wrong button and hit it early)

    #51 Tom Dayton at 13:04 PM on 26 August, 2010
    there are many more successful such experiments

    The one you have shown us is not one of them. The child in the video says:

    "This graph shows my results. The red line shows the temperature of the jar with the CO2 and the blue line shows the control jar. In the morning I put the heat lamp on for a few minutes and as you can see the jar with the CO2 heated up faster. Then, while I was at school they both cooled down, but the CO2 jar stayed warmer. When I got home I turned the heat lamp on again and the same thing happened. From this I concluded the jar with the CO2 in it heated up faster, cooled down slower and maintained the difference."

    And here is the graph:



    The two graphs are identical except for the initial divergence and a constant offset later (I have copied a portion of the red curve made yellow onto the blue one to show it). There is no way a difference in emissivity/absorptivity between two objects can produce such a result. What is more, the carbon dioxide in jar B has much lower absorptivity than the thermometers themselves, so one would expect no difference between the two jars whatsoever. And even if there were a difference, jar B would have had cooled faster, not slower, as higher absorptivity goes along with higher emissivity.

    But as I've said, there were no such difference in absorptivities, at least none within the bounds of measurement errors. So what has happened?

    As you can see jar B has started from a somewhat higher temperature right in the morning, then this difference increased fast, then stayed the same for the rest of the day irrespective of the radiation source was on or off.

    Probably there was heating in the room that was turned off for the night and switched back in the morning just before the experiment started. It developed then maintained a temperature gradient between the positions of jar A and B on the table. We would never know for sure, because the kid missed the most basic control experiment. He has failed to switch places of the jars.

    The child may be cute, but it does not make his propositions valid. His final conclusion "We expect the Earth to act the same" has nothing to do with the "experiment", in his case it is based on pure belief and indoctrination.

    It is a huge disservice to kids to let them embarrass themselves in public like that instead of teaching them proper scientific methodology by pointing out all the obvious errors.
  11. #58 Will at 20:58 PM on 26 August, 2010
    So 79% of the atmosphere is cooled by what process? Does the majority of the atmospheric mass have to transfer its energy through a bottle neck of 0.0385% CO2 in order to radiate to space?

    Not only CO2, there are others, the one major player being H2O. There is also an "atmospheric window" between 8 and 14 μm and another one called "Arctic window" above 16 μm, which is only "open" if there is very little moisture in the atmosphere. Through these windows radiation from the surface can escape to space directly.

    At ambient temperatures the only way for nitrogen to cool down is by frequent collisions with other stuff. If the atmosphere of a planet were made of pure N2 with no trace amount of anything else (it also has to be made of a single isotope of N, lets say 14N), it would not get cooler with increasing elevation. But you also have to make sure the surface was absolutely dry and dust free to make it work like that.
  12. #59 Ned at 21:05 PM on 26 August, 2010
    All else being equal, if you put Earth and Venus at the same distance from the sun and gave them the same albedo

    Albedo is not a free parameter that you can simply give. Especially for atmospheres with a stuff that can condense to droplets provided it gets cool enough (both Earth and Venus have one).

    Also, with a practically infinite supply of GHG (the store is called ocean) the response of terrestrial climate to an increased opacity in a narrow IR band may be pretty counter-intuitive. The system as a whole does not have to get warmer to maintain power flux balance, it is enough to redistribute water vapor slightly. Not even average upper troposphere humidity has to decrease in order to decrease effective photosphere height (that is, bringing down the place radiation can escape to space from to a lower, therefore warmer level). It is quite enough to let humidity distribution getting a bit more uneven.
  13. BP writes: Albedo is not a free parameter that you can simply give.

    Of course not. But your initial comment that claimed only a "5 C" increase in temperature was based on a particular assumption about the Earth's albedo. You assumed it would stay constant, which is (a) not realistic, and (b) a misleading comparison to Venus, which has a much higher albedo.

    I would repeat everything I say in my comment above, but for simplicity's sake I'll just link to it
  14. Okay, BP, the child's experiment was not airtight. (For folks whose first language is not English, that was a pun.) So for the next child let's bring in professional help from scientists and the MythBusters!
  15. #64 Ned at 23:33 PM on 26 August, 2010
    You assumed it would stay constant, which is (a) not realistic, and (b) a misleading comparison to Venus, which has a much higher albedo

    It is just as arbitrary and misleading as constructing an "Earth" with neither atmosphere nor hydrosphere but with the same albedo as it actually has, considered as a baseline to the "greenhouse effect".
  16. Berényi - On the contrary, changing a single variable is an essential method for conveying the effect of that variable.

    You could be more realistic in describing end-point conditions by looking at all the parameters, the interactions, feedbacks, etc. - but if what you wish to show (as in The Hoover Incident) is that current conditions could not hold true if that variable was changed, a single-variable approach is more than sufficient as a reductio ad absurdum proof.
  17. Will at 21:34 PM on 26 August, 2010

    Heating in Thermosphere, as in increased kinetic energy per molecule or atom?, yes. Massive top down?, no, hardly any molecules (or mass) here. Further down, the UV is quite efficiently filtered by Stratospheric components such as Ozone (Ozone level peak around 20-25 km up - where it is cold?) - so that only 1-3% of total UV (mainly longer wavelength UVA) reaches the surface. You state:

    "as the atmosphere thins it looses more energy via radiation, yet at the same time it still has an insulating effect"

    How? I'm not sure what physical processes you are trying to communicate here. Approx 99.999% of the atmosphere is below the Thermosphere. Approx 99.9% is in the Troposphere. What substance exactly is providing insulating properties where? I suspect you may be stretching the definition of "air" a little thin...
  18. #55 "For some historical context see Moe 1977."

    On the webpage we've been referred to by Will is this statement:
    The Governments of the world and the various space agencies such as NASA have conspired to stay quiet about the Diurnal Atmospheric Bulge

    In addition to the reference cited by Peter Hogarth, here's Harris and Priester 1965. Both were NASA scientists at the time.

    I found that by googling 'diurnal atmospheric bulge'; it was the 4th hit on the 1st search result page. Without opening a can of political worms, how is the existence of this phenomenon being kept secret? Note that I ask how, not why.

    And also note this reference further down the same search. One of the great things about skepticalscience is that you can quickly find a more reasoned explanation.

    Note: Any rumors that I have started a 'Ned Fan Club' are categorically false.
  19. muoncounter at 03:17 AM on 27 August, 2010

    To be fair, some of the relevant information was only declassified in 1971 (if memory serves).
  20. muoncounter at 03:17 AM on 27 August, 2010

    For some more updated classic science on the Thermosphere and Mesopause, UV heating, upwelling IR and radiative balance, see States 2000.
  21. Berényi Péter @61

    Probably there was heating in the room that was turned off for the night and switched back in the morning just before the experiment started. It developed then maintained a temperature gradient between the positions of jar A and B on the table.

    Hmm, heating that is turned on about 8.00am, and then is left on all day while he's out at school(as his caption says) and is kept on until at least 8.00pm.

    I thought the kid said he was worried about global warming !

    But at least his experiment is missing some of the glaring errors in Will's version.
  22. Will at 21:34 PM , when you say that air is both a good insulator and a top radiator, does it not depend more on the movement of the air rather than it's inherent properties?
    Still air is indeed a very good insulator of heat, however moving air is a very efficient dispersant of heat.
  23. Will writes: The problem lies in the lack of understand of the fact that the atmosphere both radiates and insulates at the same time.

    Insulates what? From what?

    The only way that the Earth loses heat is by radiating to space. The only way that I can see the word "insulation" being relevant in this process is ... the effect of greenhouse gases repeatedly absorbing and re-radiating energy from the surface, slowing its outward flux and raising the temperature of the Earth system. But that's exactly the process you claim doesn't occur, so you presumably mean something else, right?

    In addition, I'm still curious about this remark from an earlier comment of yours: Thermal radiation is heat. Vibrating matter. Gas molecules are vibrating matter. [...] In the vacuum of space full spectrum EMR produces no thermal radiation, heat.

    Thermal infrared radiation is just another part of the electromagnetic spectrum; it's called "thermal" because it's the range at which normal Earth-surface objects radiate. It obviously does propagate through space (we use thermal sensors operating in the 8-14 micrometer window to measure this from satellites).

    Oh, and not to overload you with questions, but it would be nice if you could answer the questions from this comment. At what wavelength ranges does nitrogen in the Earth's atmosphere absorb and emit radiation? Thanks.

    muoncounter writes: Note: Any rumors that I have started a 'Ned Fan Club' are categorically false.

    Hey, I like that idea.
  24. Tom #65

    The Mythbusters experiments sufferers the same problem than invalidates many Mythbusters experiments. The lack of replication and randomisation of placement of the treatments. I'd love to see someone do the experiment properly, but none that I have seen on the internet so far come close to a properly controlled, replicated and statistically analysed experiment.

    It's odd really. You'd think that every natural history museum in the World would have this sort of thing as a permanent installation.
  25. I just looked at the CO2 candle and tube demonstration of the so called greenhouse effects of absorbing heat when the CO2 fills the tube. What is not shown and is important is the spectral sensitivity of the sensor tube. Also, I would like to see the same experiment with water vapor being pumped in. I really don't think this is much of a relevant experiment concerning what is happening in our atmosphere. It seems to me that the results may be more stunning with water vapor and we should reduce that too.
  26. Re: Henry justice (76)
    "It seems to me that the results may be more stunning with water vapor and we should reduce that too."
    You do realize, don't you, that to reduce the overall water content of the atmosphere you first have to reduce it's temperature?

    Water Vapor imbalances in the atmosphere equalize in approximately 8-9 days, and is highly dependent on the temperature of the air.

    Increasing concentrations of CO2 in the atmosphere are acting as a forcing, increasing the temperature of the air sufficient to also increase the humidity of the air by 4% (about the volume of Lake Erie).

    These increases in water vapor act as a feedback to further increase temperatures.

    The Yooper
  27. Henry,

    No, additional photons are not necessary for increased warming via greenhouse effect. All that is necessary is to slow the rate at which those photons can leave the atmosphere, which is precisely what GHG's do. You seem to be under the impression that a photon absorbed by a CO2 molecule disappears forever, and as there are only so many photons to be gobbled up, additional CO2 can't make things any worse.

    Greenhouse gases don't keep the photon, they re-radiate it in a random direction. The more CO2 in the atmosphere, the more likely the recently emitted photon wil be absorbed by yet another CO2 photon, or be radiated back toward the earth and absorbed by the surface. So while the total number of photons entering the planet's atmosphere has not changed, the number of photons exiting is reduced, hence more warming.

    Do you honestly find a website hosting a rather panicked rant about left-liberals, tax hungry democrats and evil socialists to be a source of good science?
  28. John Tyndall actually measured heating in carbonic acid solutions of various concentrations (CO2 dissolved in water) illuminated by gas flames. He didn't measure the absorbance of IR in purified gases.

    Knut Angstrom, an expert is solar radiation, proved that Arrhenius' calculations were wildly incorrect and based on an improper methodology.

    The fact that the Earth is warmer than the Moon simply proves that the oceans and atmosphere of Earth have an "atmospheric warming effect". It certainly doesn't prove the existence of a "Greenhouse Effect" due to CO2 or any other gas.

    All the planets(except Mercury which has no atmosphere) have an atmospheric warming effect that correlates directly with the pressure of the atmosphere. This is regardless of the actual atmospheric composition.

    The most important source of warming on Earth is the transfer of latent heat via evaporation and condensation. This is why coastal areas have far less variation between day and night temperatures compared with deserts. This is despite the concentrations of "GHGs" being the same.

    The satellite data simply shows that the Earth is radiating more heat. This can be caused by the upwelling of warm ocean water. It does not prove the existence of any Greenhouse Effect.
    Response:

    [Daniel Bailey] Angstrom's error was in treating the atmosphere as a single layer. Later studies (of which they are legion) conclusively show that portion of his work to be in error. The GHG effects of CO2 are considered established fact. For a more in-depth discussion, see here, here and here.

    The remainder of your comment is in error. So I recommend that you also read Newcomers, Start Here and then learn The Big Picture. I also recommend watching this video on why CO2 is the biggest climate control knob in Earth's history.

  29. I'm seeing references to a paper by a Joseph Postma, also denying any greenhouse effect.
    His argument boils down to this:
    1. Thermodynamics says the effective black body temperature of the earth is -18C, and this is matched by observation from space.
    2. We observe much balmier temperatures at the earth's surface in practice.
    3. The Greenhouse Theory says the difference is down to the greenhouse effect.
    4. Postma observes that the temperature of -18C occurs at 5km altitude:
    "This altitude is found at about 5km in height above the ground surface by observation. "
    5. He calculates from more thermodynamic theory (the adiabatic lapse rate) that we should therefore expect the temperature at the surface of the earth to be 14.5C. Voila! No need for a greenhouse effect.
    The blunder, of course, is that he offers no explanation for the -18C line being at 5km. And the explanation is ... the greenhouse effect!
    He also makes this confusion on thermodynamics, which I've seen elsewhere: "something which is cool cannot transfer heat to something which is warm". Clearly he is thinking of net transfer, but that's not how he uses this principle.
  30. I don't believe it is generally agreed that falling temperatures with increasing altitute are the result of the GHE. The term is actually called the adiabatic lapse rate. Howere, I think this needs more consideration. For instance this paper by Verkley and Gerkema is relevant:

    “A column of dry air in hydrostatic equilibrium ….. bounded by two fixed values of the pressure, and the question is asked, what vertical temperature profile maximizes the total entropy of the column? Using an elementary variational calculation, it is shown how the result depends on what is kept fixed in the maximization process. If one assumes that there is no net heat exchange between the column and its surroundings—implying that the vertical integral of the absolute temperature remains constant—an ISOTHERMAL profile is obtained in accordance with classical thermodynamics and the kinetic theory of gases”

    http://www.nioz.nl/public/fys/staff/theo_gerkema/jas04.pdf

    If that would not be the case, it would be possible to build a machine that makes mechanical energy from a single source of heat. This goes against the 2nd law of thermodynamics.

    The natural intuition that the temperature must be warmer at the bottom, because molecules gain energy, when falling, is wrong because it’s exactly compensated by another phenomenon: Those molecules that have little energy cannot go up as well as those with more energy.

    This is not to deny that the sudden imposition of a gravitational field on a column of gas would
    indeed set up a temperature gradient. It would – but it wouldn’t persist. It would
    quickly be homogenized and the column would become isothermal.

    So if a column of gas behaves this way would a GH free atmosphere behave the same way too? Without the driving force of IR radiation from the upper reaches of the atmosphere there would be very little net heat flux in our column of air. There would be no re-radiation of course and very little convection. A GH free atmosphere would be very different from our present one and approximately much more closely to an isothermal state.

    So if this is the case, then we can show that the GHE has not been falsified simply by climbing a mountain and noticing that it does indeed get colder.
  31. Following from my earlier comment about our state MP who advocates against the science of climate change, here he is demonstrating that he's not just a politician but a brilliant scientist.
  32. Tristan, if he is as bright as you suggest, then I'm sure he must have an explanation as to why there is so much more downwelling IR radiation reaching the surface than what the Sun emits. That is an easy, reliable, confirmed over and over, direct, real world observation, in total contradiction with the little experiment you link above. So allow me to be a little skeptical. Where does all that IR come from?
  33. I'm certain he has an explanation. They always do.
  34. I'm certain he has an explanation. They always do.


    Don't they just?

    And the operative word is "an". The explanation doesn't need to be the correct one, because the intent here is to sow fear, uncertainty, and doubt. Purely and simply.

    Richard Pearson's target audience is the unsure, non scientifically-educated swinging voters who form a large proportion of his and his colleagues' voting constituency. Sadly, most of them are not as cooly logical as Philippe, and frustratingly there never seems to be a simple way of getting across perceptive points such as his.

    Pearson doesn't need to be right; he just needs to be convincing.
  35. There is a basic flaw in the paragraph

    Empirical Evidence for the Greenhouse Effect

    We only have to look to our moon for evidence of what the Earth might be like without an atmosphere that sustained the greenhouse effect. While the moon’s surface reaches 130 degrees C in direct sunlight at the equator (266 degrees F), when the sun ‘goes down’ on the moon, the temperature drops almost immediately, and plunges in several hours down to minus 110 degrees C (-166F).

    The flaw is that the cooling rate on the Moon is significantly slower than your article suggests and even NASA state :-

    “During lunar day, the lunar regolith absorbs the radiation from the sun and transports it
    inward and is stored in a layer approximately 50cm thick. As the moon passes into night,
    the radiation from the sun quickly approaches zero (there is still a bit of radiation from the
    earth) and, in contrast with a precipitous drop in temperature if it was a simple black body,
    the regolith then proceeds to transport the stored heat back onto the surface, thus warming
    it up significantly over the black body approximation.”

    Contrast this with the fact that Earth's atmosphere obviously reduces the heating "power" during the day and you have empirical evidence that atmospheres reduce surface heating of planets - not the reverse.

    I expect this comment to be deleted but it was enjoyable posting it.

    (-snip-).
    Response:

    [DB] Sloganeering snipped; moderation complaints struck out.

    All parties please note: Rosco's Moon comparison has been previously rebutted, most recently here. As such, it is to be treated as sloganeering and subject to moderation.

  36. Rosco, your remark is unlikely to be deleted and your enjoyment will probably be brief. :-)

    Starting with: based on Rosco's analysis, may we conclude that Earth's moon has an atmosphere comprised of regolith?
  37. doug_bostrom - it is not my analysis - I have quoted NASA.

    (-snip-).
    Response: [DB] All parties please note: Rosco's Moon comparison has been previously rebutted, most recently here. As such, it is to be treated as sloganeering and subject to moderation/snipping.
  38. Rosco - Your comments here are interesting, but perhaps not in the fashion you intended.

    Rather, they show what errors occur when you don't take all factors into account.

    Convection and latent heat indeed cool the earth, pushing heat into the upper atmosphere where it can be radiated. If the atmosphere lacked convection, we could readily expect temperatures perhaps another 40-45°C warmer than currently exist. We are indeed fortunate that convection exists, that atmospheres become unstable and convect with warming, that evaporative processes move energy away from the surface.

    But without the greenhouse effect (in a Gedankenexperiment consideration, as certainly other things would change with such a physical modification), without significant radiation from high in the cold atmosphere rather than the warmer surface, the Earth would be ~33°C colder than current temperatures, on the order of -16°C to -18°C.

    Heating and cooling of the lunar regolith are indeed factors in the moon's average temperature. But that average is quite a bit cooler than the Earth's temperature (in fact, if the Moon had an equivalent atmosphere, it would be warmer, as the albedo of the Earth is rather higher - 0.3 as opposed to the Moon's 0.12).

    If you take all of these factors into account, rather than focusing on a single factoid (defined as a piece of information smaller than a useful fact), the radiative greenhouse effect has just the influence predicted by the physics of spectroscopic absorption, emission, and the atmospheric lapse rate. And that's ~33°C warmer than we would be without the greenhouse effect if that was the only change.
  39. Rosco, the mean surface temperature of the Moon at the equator is approximately 206 degrees Kelvin. For comparison, the mean daily temperature in August (the coldest month) at Vostok Station (the coldest place on Earth)is 205 degrees Kelvin. In other words, the means surface temperature of the hottest location on the Moon is the same as the mean surface temperature of the coldest location on Earth when it is at its coldest. The mean annual temperature at Vostok Station is actually just over 10 degrees K warmer than the mean annual temperature of the Moon at the equator.

    As it happens, the Moon has a lower albedo than the Earth, so all else being equal, it should be warmer than the Earth, yet it is colder.

    Can you explain how your theory that the Earth's atmosphere cools the Earth is compatible with these facts?
  40. Rosco, what happens at the top of the atmosphere-- where convection ends?

    Also, you need to do some research on why the ISS employs radiators. Start with something simple, like the Apollo spacecraft. Try here: history.nasa.gov.
  41. Roscoe,

    I see no conflict between your quote from NASA and the article. According to you, the article states "the temperature drops almost immediately, and plunges in several hours down to minus 110 degrees C". NASA says "in contrast with a precipitous drop in temperature if it was a simple black body,
    the regolith then proceeds to transport the stored heat back onto the surface, thus warming
    it up significantly over the black body approximation"

    A black body would drop to -110C almost immediately. If it takes "several hours" as the article says, that is "significant warming" as NASA says. The problem is you are reading the articles incorrectly. Perhaps you should read the article again to clarify the data. Just because you do not understand the data does not mean everyone else does not understand it also.
    Response: [DB] All parties please note: Rosco's Moon comparison has been previously rebutted, most recently here. As such, it is to be treated as sloganeering and subject to moderation.
  42. Michael Sweet @91, if no heat was stored in the Moon's regolith, temperatures would fall to 2.7 degrees K at night, that being the temperature of the cosmic background radiation. The near constant night time temperature contrasts sharply with the presumed behaviour of a "simple black body". (Of course, there is nothing in the nature of black bodies per se from retaining heat, and therefore not instantaneously matching incoming radiation with outgoing radiation with the same power.)

    As a matter of interest, I have googled Roscoe's quote and found it on several denier documents without citation. Therefore, the attribution of the quote to NASA must be considered suspect until the source of the quote is cited and linked to.
  43. As an interesting thought experiment - would a cubic blackbody have a different temperature to a spherical one ?
    Response: [DB] Please note that Rosco has recused himself from further participation in this venue (essentially a meltdown/temper tantrum).
  44. Well, Rosco, (-snip-).

    There is plenty of information available on the subject, from NASA and other sources, with which you are obviously not familiar. I will not bother linking anything because, if you have any sincerity, you will find it quite easily, no help needed. Your argument is not well constructed, it is a delirious case of Dunning-Krueger effect.

    The fact that you feel that you can come here and lecture not only on planetary science but also on moral principles is laughable. The kicker was putting together the idea of a well thought out argument and that of a square planet. Thanks for the entertainment. (-snip-).
    Response: [DB] References to deleted comments snipped by request.
  45. To any casual reader who wanders by and reads Rosco's approach to science...

    This exemplifies why it is important to do the math, and to actually quantify the effects in question. It is very easy to "consider" and to do "thought experiments." With a wave of the hand, the dark side of the moon has 720 hours to cool and look, a sweltering motorcycle shop needs fans.

    It's so easy when you do everything by analogy, with none of that highfalutin mathematics and calculations and fancy numbers to get in the way.

    Don't do science by thought experiment and "obvious" conclusions. Run the numbers. All of them, not just the ones that conveniently seem to demonstrate the point that you'd dearly love to be true.
  46. Further to Sphaerica's comment, I might add that if, like me, you don't have the skill set to do the maths yourself, link to someone who does.
  47. Adding to Sphaerica's comment:

    Frequent errors in these discussions are attempts to argue back from analogies.

    Analogies are useful "forward" explanations - complex system A is (in part) analogous to a more familiar system B (to portions thereof), and if your listener has context on B that can be useful in explaining relationships in A as "like" those in B. Energy balance in the climate is like a dam in a river, or the radiative greenhouse effect is like a blanket, for example.

    But those analogies cannot be used for "backward" testing, as there are portions of the complex system A that are not mapped in B, and portions of B that have no corresponding element in A - and assuming that the mapping is 1:1 is an error. Hence arguments such as from motorcycle shops to lunar regolith, or for that matter many of the "2nd law" or "Slayers" objections to the greenhouse effect, are simply meaningless nonsense, handwaving.

    An analogy is a useful explanation. But testing theories about complex systems needs to be done in those frameworks, using numbers, using math, with the actual relationships - not in a partially mapped analogy that is not the system in question.
  48. There is a very simple explanation for the 33 degrees extra temperature on planet earth and it is basic high school science from around 10th grade. PV=nRT ,Avagadro number and all that.Pressure is proportional to temperature. This also explains why temperatures fall(1 degree per 200 metres) with altitude and rise in the deep sub sea level areas of the earth. As for planet Venus, apart from being closer to the sun, pressures are 92 times that of Earth at the surface.
    As on Earth,temperatures fall with altitude. You would think that temperatures would be more even in the atmosphere of Venus if the "runaway greenhouse" were for real. The same effect I think occurs on Jupiter- the outer gas is cold, but deeper in the atmosphere as the pressure builds, it is considerably warmer.
    Think how refrigerators work- they compress the refrigerant gas, which get warm. The heat is radiated out, then when the pressure is released, the gas cools to allow us to have that icy cold beer on a stinking hot day.
    I lay down the gauntlet for some physicist out there with more brains than myself to check this simple hypothesis and gain immortality and cudos.
  49. "For every complex problem there is an answer that is clear, simple, and wrong."

    High treason, your hypothesis fails to explain why the stratosphere warms with altitude. Perhaps more reading is in order?
  50. JasonB @99, he also fails to explain why temperatures fall with increasing pressure as you go deeper into the ocean. He tries to conceal this by asserting that:

    "PV=nRT ,Avagadro number and all that.Pressure is proportional to temperature. This also explains why temperatures fall(1 degree per 200 metres) with altitude and rise in the deep sub sea level areas of the earth."


    But, of course, temperatures do not rise in the ocean abyss except at the sites of volcanic vents. Even there, while the water emitted from the vent may be as warm as 400 C, within meters of the vent the ambient temperature is a frigid 2 degrees C.

    Worse for high treason, the ideal gas law alone is not sufficient to explain the temperature profile of the troposphere. You also need to employ the laws of thermodynamics, the universal theory of gravitation, and the assumption that convection is the main form of heat transfer within the troposphere.

    And worst of all for high treason, he forgets is earliest lessons in algebra. Taken together, basic physical law explain the approximate -6.5 C per kilometer altitude temperature profile of the troposphere; but that only gives you a line with a slope. Knowing only the slope, you cannot deduce the intersection with the x-axis, ie, the surface temperature.

    Not only has he got his high school science wrong - he can't even get his primary school maths right.

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