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Climate Hustle

Is CO2 a pollutant?

Posted on 11 February 2010 by John Cook

We commonly think of pollutants as contaminants that make the environment dirty or impure. A vivid example is sulphur dioxide, a by-product of industrial activity. High levels of sulphur dioxide cause breathing problems. Too much causes acid rain. Sulphur dioxide has a direct effect on health and the environment. Carbon dioxide, on the other hand, is a naturally occuring gas that existed in the atmosphere long before humans. Plants need it to survive. The CO2 greenhouse effect keeps our climate from freezing over. How can CO2 be considered a pollutant?

A broader definition of pollutant is a substance that causes instability or discomfort to an ecosystem. Over the past 10,000 years, the level of atmospheric carbon dioxide in the atmosphere has remained at relatively stable levels. However, human CO2 emissions over the past few centuries have upset this balance. The increase in CO2 has some direct effects on the environment. For example, as the oceans absorb CO2 from the atmosphere, it leads to acidification that affects many marine ecosystems. However, the chief impact from rising CO2 is warmer temperatures.

Figure 1: CO2 levels (parts per million) over the past 10,000 years. Blue line from Taylor Dome ice cores (NOAA). Green line from Law Dome ice core (CDIAC). Red line from direct measurements at Mauna Loa, Hawaii (NOAA).

Rising CO2 levels causes an enhanced greenhouse effect. This leads to warmer temperatures which has many consequences. Some effects are beneficial such as improved agriculture at high latitudes and increased vegetation growth in some circumstances. However, the negatives far outweigh the positives. Coast-bound communities are threatened by rising sea levels. Melting glaciers threaten the water supplies of hundreds of millions. Species are becoming extinct at the fastest rate in history.

How we choose to define the word 'pollutant' is a play in semantics. To focus on a few positive effects of carbon dioxide is to ignore the broader picture of its full impacts. The net result from increasing CO2 are severe negative impacts on our environment and the living conditions of future humanity.

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Comments 101 to 150 out of 252:

  1. From Peru, I think that is almost a certainty. It's easy to accept that nearly 8,000 years of agriculture would have some impact on CO2 concentrations in the atmosphere. Yet compare 20ppm over 8,000 years to around 100ppm in the last 250 years (with the bulk being in just the last 60 years). It really suggests that the Industrial Revolution is a much bigger threat to our atmosphere than the previous Agricultural Revolution.
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  2. I know we're discussing the science-& not the economics, of CO2-emissions, but I think RSVP's claims need to be addressed. The idea that reducing anthropogenic CO2 emissions will come with great economic pain, for all, is often the "last line of defense" of the contrarian camp. Yet this is, in fact, far from the truth. Around 30%-50% of all electricity use, across the world, is the result of energy inefficiency in the domestic, commercial & industrial sectors of the economy. Similarly, about 20% of all fuel use is due to inefficient use of transportation. So here we have measures for reducing CO2 which-far from being painful-might actually *improve* economic well being. Aside from direct efficiency issues, there are also things like Co-generation, moving freight long distance by rail rather than road, increasing the use of car-pooling, public transport & tele-commuting to eliminate peak-hour traffic snarls & improvement in street lighting to reduce lighting scatter & thus eliminate light pollution & allow for lower wattage globes.
    Beyond this there are things like using methane from land fill & sewerage plants to generate electricity-thus killing 2 birds with one stone-& implementing bio-sequestration at all fossil fueled power stations. So, even without considering electric vehicles or solar/wind/tidal power, we already have a host of measures at our disposal for reducing CO2 emissions with no long-term harm (&, in fact, with long-term economic & health benefits).
    Of course there is also the need to consider our obsession with perpetual economic growth. Instead of focussing on ever-increasing GDP growth, our society should instead focus attention on increasing GDP/capita. Remove this "need" for perpetual growth, & many of our current economic & environmental problems might just start to solve themselves!
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  3. Another point I'd like to make is in relation to RSVP's attempt to blame warming on thermal pollution rather than CO2. If his claim were correct, then industrial centers would be warming significantly faster than non-industrial &/or rural sites. Yet there is no noticeable correlation between warming & industrial activity up into the lower troposphere. Indeed, some of the fastest warming places on Earth are places like Antarctica & the Arctic, yet last I looked there were no Steel Mills or Aluminium smelters in these locations!
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  4. @ 81 & elsewhere : I see here the nearly universal misconception , and if really thought about - shear nonsense , that albedo of a radiantly heated uniform gray ball affects its equilibrium temperature . That this leads to absurdities such as being able to construct a cryogenic cooler just by coating the inner chamber of a vacuum bottle with MgO was Kirchhoff's great insight 151 years ago . This ubiquitous error , which comes from calculating the temperature of a ( gedanken ) body which reflects with a measured albedo , but emits as a black body , is the source of the misleadingly cold numbers , such as 255k for earth upon which the notion that GHGs account for about a 33c increase in our temperature . Far more relevant , and orthogonal , is that , as calculated on my , we are about 9c warmer than a gray body in our orbit . Our temperature is linear with that of the sun , and inversely proportional to the square root of our distance from it . See for the graph which shows that Venus is the only inner planet which consequentially deviates from those functions beyond observational precision .

    Even a disk , black facing the sun , white facing 3k space in Venus's orbit would only be about 390k .

    Since since the SB law for radiant heat transfer is T ^ 4 from hot to cold , and Fourier for conduction is down the gradient of Temperature , and convection is also , by Carnot at a minimum , hot to cold , how can the surface temperature of Venus exceed the energy it is receiving from the sun unless it has some substantial internal heat source . There is no question that blankets can keep heat IN , and the heat conductivity of CO2 at . what , 90 atmospheres , would be very interesting to know .

    It happens my bathtub reading this year is a dog chewed copy of my niece's electrodynamics textbook at Boulder . Compared to it , the understanding of the physics displayed by both sides of this debate is pathetic .
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  5. Marcus
    We are all inhabitants of a beautiful planet that everyone wants to conserve. In that sense, we are all in the same camp.

    I am not sure which post of mine got you going on this thing about a "last line of defense". At some point, I was asking about comparative technologies and impact studies. SNratio accused me of being political for asking these questions, which only science and engineering can answer.

    Believe it or not, I am the first to "wish" CO2 levels were back to "normal". If there was a magic wand to wave, I would be the first to wave it.

    However there is no magic wand, in the sense that reducing CO2 emissions does have an unavoidable economic burden simply due to the inertia of current capital investment. Things are precarious as it stands. It is not a political statement. It is a fact. (Example. I have an automobile I can barely afford to drive, and it is not an expensive automobile by the way).

    What could be a "last line of defense" for the cold winter we are having than to say it would actually be colder if it wasnt for anthropogenic warming? This comes out over and over again (and even if this were true, I for one am not complaining. It's suppose to snow today, again).

    If it helps you understand where I am coming from, all I can say is that I try to separate what I wish for from my beliefs or assessment of the technical issues. To be concrete, I find it very difficult to swallow this pill that claims that a .01% or .02% volumetric increase of a gas in our atmosphere is driving planet temperatures dangerously upwards. Like tying a mouse to a refrigerator and expecting to see it move. It just isnt intuitive, now matter how many "peers" signoff.

    One of the first things I ever posted, was that you can't destroy matter or energy. As far as your second comment, 104, urban centers do tend to be comparably warmer than surrounding rural areas. Winds typically clear out this extra heat and make city life livable, however that heat doesnt just go poof, because as I just said, you cant destroy energy. It either needs to find its way to the black of space, or be absorbed here and elevate the Earth's temperature. At some point this energy turns ice into water, and then people take notice. In this case, the location of cause and effect can be thousands of miles apart.
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  6. Marcus
    If you will allow me to add a small touch to my last comment.

    So the path for heat outward is radiation into space. And greenhouse mechanisms obstruct this path as they should. Extra CO2 does indeed increase this obstruction.


    The real problem is not this path. The real problem is the additional heat needing to use this same path.

    Like a highway with traffic. All it takes is one accident to create a giant slowdown. The traffic is due to the fact that the highway is already saturated. Now you have more cars plus an accident.

    The point here is that you cant avoid generating the extra heat, which accompanies all technologies.
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  7. Marcus, I agree. I am often struck by the way in which a single comment will combine an absurdly high degree of "skepticism" towards mainstream climate science with a completely speculative assumption about the costs of action to mitigate climate change.

    There is a lot of peer-reviewed work that's been done on assessing the economic costs and viability of actions to reduce the magnitude and impact of climate change. We could start out with Pacala and Sokolow 2004 and go on from there. But in my experience, very few of the skeptics/contrarians/denialists (whatever term you prefer) are aware of, or interested in discussing, that part of the literature. They tend to just take it for granted that reducing anthropogenic CO2 emissions will obviously cost immense sums of money so why bother to even discuss it?
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  8. Whoops, sorry for misspelling Socolow.
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  9. John - I've been arguing with a rabid sceptic/denier on a sceptic website and he came up with the "argument" below

    CO2 for the past 80 or 90 years has been increasing in the atmosphere at the rate of 2ppm. To double from its current 385 will therefore take almost 200 years

    His point was based on that if climate sensitivity estimates are that temperature goes up about 3 degrees C per doubling then we have far longer to wait or act (or not be bothered to act)than the IPCC view.

    This looked like a new denier argument to me that I hadn't seen before. I pointed out that IPCC graphs of projected CO2 levels must take into account increased outgassing of sequestered carbon from the oceans and permafrost as things warm up (which must, if his math about PPM/year stacks up, be much much greater than our emissions).

    He responded that if the oceans etc were warming due to a natural cycle, or indeed us, then we haven't seen anything like an acceleration in the CO2 ppm/year rate yet.

    On the face of it, his argument does seem to show that CO2 levels are not rising at a dangerous rate yet. I have my own ides about how to answer this conundrum but what am I missing?
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  10. Bob Armstrong, 105, you've made at least one basic error. Real materials are not grey bodies; their actual emissivities are functions of wavelength. Therefore, the earth's albedo in the visible wavelengths does not set any requirements on the earth's emissivity in the IR wavelength range.

    This becomes even more important with greenhouse gases, which are very much different from grey bodies.

    In general, if you think you've applied some introductory level physics and discovered a major flaw in a scientific field, you should probably re-examine.
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  11. CO2 for the past 80 or 90 years has been increasing in the atmosphere at the rate of 2ppm. To double from its current 385 will therefore take almost 200 years

    The rise in CO2 concentration IS accelerating -- in the 1960s it was increasing at less than 1 ppmv/year; now it's increasing by over 2 ppmv/year.

    The discussion of "doubling" generally refers to doubling from its preindustrial concentration (i.e., going from 280 ppmv to 560 ppmv), which, if you project the past 50 years' accelerating trend, will happen sometime around 2070. That seems like a long time from now but it's well within the expected lifespan of my own daughter. Doubling from the current concentration would happen a few years after 2100.

    The oceans are not the source for the rise in atmospheric CO2 -- in fact they're taking up CO2 from the atmosphere. The 2+ ppmv per year increase in atmospheric concentration is only a small portion of what we're emitting. The rest goes into the oceans (where it has the side effect of decreasing the pH). See the work of Takahashi et al. over the past couple of decades, which has amply demonstrated this.
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  12. carrot eater , Real materials are much closer to being gray bodies than to emit as black bodies . Furthermore , a flat spectrum , gray , term is orthogonal to the correlations between the spectra of an object and its sources and sinks making it the appropriate first term like extracting the mean as the first term in any series expansion . I see no evidence that anyone here is capable of arguing with actual equations in which case we could work out the transformation of your non-orthogonal equations to my orthogonal . I think the confusion caused by your starting point is a reason why I have never found a complete quantitative algorithm for calculating "forcings" .

    I repeat , I find the understanding of the physics pathetic on both sides of the debate .
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  13. Find the critical question of c02 buffering poorly handled in many of your summaries . Where is the Co2 being measured apart from ice cores? I want you to show where in the atmosphere and on the earth it is being measured and monitored ( over time too ) - otherwise the buffering equations and their significance remain in doubt .
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  14. Thanks Ned
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  15. Bob Armstrong: The actual emissivities and albedos of different materials found on the Earth have been measured, and go into the relevant calculations. You can look them up. You can also look up the absorption spectra of real materials. Over short wavelength ranges, you can sometimes get away with the grey-body approximation. A wavelength range spanning the visible and the far IR is not a short range at all.

    You will have experienced this yourself. The emissivity of common paints are often in the range 0.9 to 1.0, regardless of whether the paint is white or black. But this emissivity is referring to the IR range. The absorptivities in the visible range are of course dependent on the color, and the wavelength.

    Again, if you think memories of your physics class are somehow leading you to a simple insight that invalidates an entire field, you are most likely mistaken.

    As for quantitative algorithms for calculating forcings: There's a good reason why you haven't seen one simply presented. For greenhouse gases, they require much more computation than can be easily presented. It requires the calculation of absorption and emission of radiation throughout the atmosphere, keeping track of spectral detail (since CO2 and water are extremely far from being grey bodies, with specific absorption bands due to vibrational modes).
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  16. My point, RSVP, is that some people who want to retain the Status quo (because its in their own self-interest) massively overstate the cost of reducing CO2 emissions. Here's a case in point-my own CO2 footprint just for household electricity was approximately 12kg per day & I was paying somewhere in the order of $2.80 per day for electricity. Then I replaced my inefficient electric hot water tank with a continuous flow gas system & switched all of my lights to compact fluorescents & through these efficiency measures managed to cut my electricity use to around 6kw/h per day, which cut my daily CO2 emissions to less than 6kg & reduced my electricity bill to around $1.50 per day (in spite of a price hike of nearly 10c/kw-h over that time period). I'm also saving money on light globes, because compact fluorescents last for *years*! So my personal reduction of CO2 emissions-though it carried an initial cost-will almost certainly save me huge amounts of money over the rest of my life. The same goes for driving. I choose to catch a bus to work, because keeping fuel in my car for my daily commute would cost me about $14 per day (let alone the cost of parking, registration, insurance & maintenance). By using the bus or train, I am spending a *maximum* of $8/day (& usually closer to $6/day) & am also cutting my transportation based CO2 emissions. Now, imagine tif *everyone* took these similar measures-think how much our CO2 emissions would be curbed, but without long-term cost to the individual. Indeed, over time these individuals would find themselves financially better off (not to mention less stressed because of less time spent in traffic jams). Other measures exist that will have an equally beneficial impact on CO2 emissions-without carrying a long-term cost burden to society-but still we're told by certain people that we can't do it without "massive social & economic upheaval". My point is that this kind of defeatist mantra is completely & utterly *wrong*, as I've proven via my own personal experiences.
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  17. This entire discussion is flawed by the lack of a standard against which to measure what is "too much" or "enough" or "too little to be a problem."

    There is of course no science whatsoever - none, nada, no how -- to establish that OUTSIDE THE LABORATORY CO2 causes the Earth to warm.

    As I note elsewhere, CONVECTION is a dominant mechanism in the atmosphere that MOVES heat from the Earth's surface up to near space, where the heat is radiated to outer space.

    CO2 in the atmosphere MOVES.

    It is not anchored in place.

    So if CO2 absorbs heat, AND THEN MOVES by convection (as it must), this may simply increase the efficiency of the cooling mechanism of convection.

    Heat trapped near the Earth's surface is transported more efficiently to the upper atmosphere, and radiated into outer space.

    The point being that what we observe in the laboratory where a sample of gas is TRAPPED and unable to move is not meaningful for predicting how CO2 behaves int he open atmosphere.

    However, the question of what is the "RIGHT" amount is not science.

    It is simply an ego-centric and subjective belief.
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  18. JonMoseley, there is actually rather alot of science proving that CO2 warms the Earth's atmosphere... even outside of laboratories. Several examples can be found here.

    As to your convection hypothesis... it fails because, amongst other things, greenhouse gases do not retain heat within themselves. They absorb and then immediately re-emit the infrared radiation. Since this energy is re-emitted in an essentially random direction this means that some of the infrared radiation traveling from the Earth's surface up and out into space is instead reflected back down to the planet by greenhouse gases.

    If you refer back to the link above you will see that it includes direct evidence of this absorption and re-emission in that radiation escaping the atmosphere shows a reduction in the wavelengths absorbed by carbon dioxide while radiation coming down from the atmosphere shows an increase in those same wavelengths.
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  19. CBDunkerso
    ...........As to your convection hypothesis... it fails because, amongst other things, greenhouse gases do not retain heat within themselves. They absorb and then immediately re-emit the infrared radiation.....

    Well surely if the IR radiation is immediately randomly re radiated and all this happens at the speed of light then the time delay introduced by CO2 in a 17Km troposphere would be completely negligible.

    A thought experiment
    If co2 were completely absent from the atmosphere and instead we had extra N2 to take their place what THERMAL CHANGE would this produce.
    (Ignore chemical and biological change for the moment]
    I have the feeling that the atmosphere would remain much the same.
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  20. suibhne, replacing all CO2 with N2 would result in much less slowing of the Earth's energy loss to space, because N2 is not a greenhouse gas. Technical explanations are easy to find, but here is a concise one from Wikipedia:
    Although contributing to many other physical and chemical reactions, the major atmospheric constituents, nitrogen (N2), oxygen (O2), and argon (Ar), are not greenhouse gases. This is because molecules containing two atoms of the same element such as N2 and O2 and monatomic molecules such as Ar have no net change in their dipole moment when they vibrate and hence are almost totally unaffected by infrared light.
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  21. Tom Dayton
    I was in part answering post 119, who if correct with instantaneous absorption and emission of IR, would imply almost that nothing had happened and since IR moves at 3*10^8m/s, then any delay is negligible.
    Water vapour is still in the atmosphere(in much greater quantities) and is an even better IR absorber.
    Further conduction from Earth surface by all atmospheric gases plus convection including wind will distribute and even out the Earths surface temperature
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  22. suibhne:

    It isn't a matter of a time delay. The issues are that CO2 radiates back towards the Earth (the surface sees more radiation than it used to), and that the emission that finally makes it out to space is emitted from higher up in the atmosphere, where it is colder (less radiation is leaving the earth system than is arriving, so the system has to warm up). With nitrogen, you get none of that.

    By the way, CO2 doesn't always instantly radiate a photon as soon as it absorbs one. It can collide with neighboring molecules and thus warm up that pocket of air. But that's still fine; the CO2 will still emit at some rate set by the local temperature.

    These sorts of things are easily learned about in a textbook that covers radiation transfer in the atmosphere. I suggest simply getting one.
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  23. Bob Armstrong:

    Please review more carefully what Kirchhoff's law actually requires. It should be in any decent physics book. It does not require materials to be grey bodies, which is good because we can clearly see that they are not. Things do have different colors, after all.

    It only requires that the absorptivity and emissivity be equal to each other at a given wavelength. It does not require either quantity to be constant over wavelength.

    You can see this emipirically. Look up the emissivity of snow. In the wavelength range where snow might emit (long IR), the emissivity is close to 1. But of course snow is a poor absorber of visible light.

    Wavelength matters.
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  24. Bob Armstrong, on the issue of how long CO2 levels remain elevated (your other points having been addressed by carrot eater)... you should consider the ice core record. You dismiss estimates of centuries as ridiculous, but in fact every time there has been a CO2 increase of ~100 ppm (which is about where we are over the pre industrial revolution level) in the ice core records it has taken place over a period of a few thousand years... and then required ~100,000 years to return back down to the previous level. Mere centuries are thus a very 'hopeful' estimate when compared to every past instance for which we have data.

    It is unfortunate that you are so certain of the validity of your errors. Had you shown a more open mind you might have learned something.
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  25. Here's an augmentation of CBDunkerson's response regarding CO2 "lifetime": CB used the correct phrasing "how long CO2 levels remain elevated," because that is what matters--the total amount of CO2, not which individual CO2 molecules make up that level.

    Often the blogosphere uses the ambiguous term "CO2 lifetime." That can be taken to mean "duration of an individual CO2 molecule's residence in the atmosphere," which is irrelevant. If one molecule (Lucy) is absorbed out of the atmosphere, with the consequence that that particular absorbing mechanism now cannot absorb a different molecule (Ethyl) which newly has entered the atmosphere, then the level of CO2 has not dropped due to the absorption of Lucy. Lucy and Ethyl can play tag forever, with one at a time being in the atmosphere, with the consequence that the level stays constant.

    What matters is the balance between emission and absorption, from all sources and sinks. When emission increases faster than absorption, the level in the atmosphere increases, despite the constant swapping of individual molecules.
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  26. Tom Dryton and carrot eater
    It seems to me you are in need of some grounding in thermodynamics.
    Could I recommend Equilibrium thermodynamics by C.J.ADKINS
    The mechanisms you describe seem contradictory and unphysical.
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  27. suibhne, you believe Tom Dayton and carrot eater are laboring under a misunderstanding, but you don't explain how. Could you do that? Thanks!
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  28. suibhne

    If your complaint is going to be based on the Second Law, then rest assured that nowhere in the system is there a net flow of heat from a cold point to a warmer point. Heat is always flowing in the correct direction.
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  29. For anyone who wants to see a reasonably detailed deconstruction of Bob Armstrong's arguments, I recommend his and my exchange at S&R here, down toward the bottom:

    Furthermore, I dealt with the bulk of his arguments using physics (complete with the math, calculations, derivations, etc.) in three documents also available at S&R:

    Bob never responded after I posted the last two .pdfs, yet here we find him making some of the same wrong claims that I am pretty confident I disproved.

    The only argument he made at my site that I didn't take on is his MgO sphere example from above, but I'm pretty sure that he's misunderstood it badly. I think that the power in the interior of his hypothetical room should be constant, so the MgO ball ends up being the same temperature as the room no matter what it's albedo is (power density drops as r^2 as you leave the walls of a spherical room and move toward the center, but the area of the sphere drops as R^2 too, leaving the power constant). But I didn't prove it rigorously with calculus.

    If anyone reads those docs and sees major flaws in my math, please let me know. I'm planning on using the Venus doc as a baseline for a "debunking this bad argument" post at some point (or maybe John can. :)
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  30. carrot eater 129
    The peer reviewed Gerhard and Tscheuschner paper removed the "Greenhouse Effect" (which labelled co2 as a threat to humanity) from the realms of serious scientific study.
    Since it was published in March 2009 there has been no peer reviewed refutation of their position
    If a successful challenge to G&T is to happen I would expect it to come from say a Professor specialising in Heat Transfer Thermodynamics
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  31. Correction to 131 Gerhard Gerlich and Ralf Tscheuschner
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  32. That G&T stupidity actually got published? In a real scientific journal? I'm gonna guess GRL, E&E, or something I've never heard of before... and probably never will again.

    I remember when they first self published it a couple of years ago. After about 50 pages it got to be too much, but I remember they couldn't figure out a simple effective temperature equation (objecting that factors of 0.7, which comes from albedo, and 0.25, from 1/r^2, were just 'made up'), insisted (repeatedly ad nauseum) that since the 'greenhouse effect' does not work the same way as an actual greenhouse it cannot exist, and claimed that Fourier and Tyndall never said anything about gases warming the planet - that was just 'made up' by Arrhenius.

    It is a work of pure denial... complete with lengthy screeds against 'evil warmists'. It reads like one of Bob Armstrong's 'everyone who has ever studied science other than me is an idiot' posts rather than any kind of scientific study.

    Please, if you think there is ANY validity to that paper, quote or summarize some argument from there which ISN'T completely ridiculous.
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  33. #
    CBDunkerson 133
    I'm afraid it was published in a Physics journal which is perhaps why you haven't heard of it.
    Until a peer reviewed refutation of it appears then it must be considered to be the best Physics take on the topic. That's the way it works in science I'm afraid.
    Just repeating to yourself "it is rubbish" ten or more times will not alter the situation
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  34. suibhne,
    Gerlich and Tscheuschner paper was originaly an arxiv papaer in 2007. It has been widely refuted in many ways (for example here). It took two years to get published somewhere but it's essentially the same. There are two ways of refuting a paper, comment on it or ignore it. Now the latter will suffice.
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  35. Riccardo
    The "refutation" you cite is a non peer review paper by Arthur P Smith
    If you go to his own websites you will find that this attack have backfired.
    A contributor to this threads has been Fred Staples a Physicist whose was responsible for heat transfer in a nuclear power plant.
    He patiently and with good manners demolishes this attack because his understanding of thermodynamics is far superior.
    If you Google Arthur p Smith, not spaghetti,the arrogance of physicists, you can catch up with his thread.
    Currently Smith has boxed himself into a corner by saying that a gas molecule moving upwards in the Earths Gravitational Field would remain at a constant temperature.
    This as any high school physics student knows is rubbish.
    Typical High School Physics Question is" using the kinetic theory of gases calculate the rms speed of a N2 molecule at STP and if this molecule moved vertically upwards how high would it get, what would happen to the temperature as it went higher"
    (Answers 517m/s,13.6Km,drops constantly)
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  36. Suibhne wrote, "Until a peer reviewed refutation of it appears then it must be considered to be the best Physics take on the topic. That's the way it works in science I'm afraid."

    No... it really isn't. As has been explained on this site before, 'peer review' does not mean 'proven true' or even 'best available science'. What it is SUPPOSED to mean is that the text has been reviewed to identify and eliminate any obvious errors and conforms to standard scientific practice. You still haven't said where it was published, but it can't have been in any journal with any kind of solid reputation because that study is just complete nonsense.

    Note that I cited specific errors and failings in the text and you respond only with an unfounded assertion of the paper's 'truth'. Again, CITE where exactly it disproves greenhouse warming. You claim it does this, so you must be able to show where.
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  37. CBDunkerson
    The peer reived article you inquired about
    G. Gerlich, R. D. Tscheuschner:
    Falsification Of The Atmospheric CO2 Greenhouse Effects Within The Frame Of Physics.
    International Journal of Modern Physics B, Vol. 23, No. 3 (30 January 2009), 275-364

    Perhaps if you have any specific criticism after reading the paper you can set these out in a formal way.
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  38. suibhne, the Gerlich and Tscheuschner article has been thoroughly discredited in multiple places by multiple people. One list of those is at RealClimate.
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  39. I knew this was headed towards G&T.

    Sometimes a paper is just so bad in elementary ways, it isn't worth the trouble of a formal response. Among many errors (and much misplaced arrogance, and irrelevant discussions of glass greenhouses), they seem to think there's a violation of the Second Law in the greenhouse theory. There is not. Heat always flows the right way, in the theory.
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  40. suibhne said, "Until a peer reviewed refutation of it appears then it must be considered to be the best Physics take on the topic. That's the way it works in science I'm afraid."

    So I take it that means that you accept that all other publications since that time are now the best physics, replacing G&T? They are, after all, newer.

    This is silly.
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  41. suibhne,
    Staples, in turn, has his share of misinterpretation of how the radiative balance of the surface-atmosphere system works. Trying to falsify the atmospheric greenhouse effect just because it depends on the number of, he thinks, arbitrary layers is really straw man. Is this supposed to be the backfire? This is really graduate level climatology.

    But anyway, "It has been widely refuted in many ways"
    read those many others if you don't like that one and also look at the basic mistakes in Gerlich paper an average physics student will notice.
    Hint #1: wrong application of the second law of thermodynamics.
    Hint #2: the radiative balance and net fluxes
    Hint #3: thermal conductivity of the atmosphere

    Don't need to continue, there's clearly much more. Any interested reader will easily find information over the internet or find them by himself in the paper.
    The real question here should be how come that such a pedantic and aggressive (they talk about "scienti c fraud") paper made it through peer review in Internation Journal of Modern Physics.
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  42. Suibhne, International Journal of Modern Physics B? Nope, never heard of it. Not surprising given its 2008 impact factor of 0.558. Still, an actual indexed scientific journal published G&T. How very sad for them.

    I already listed some of the paper's blatant flaws. I note that you still refuse to cite a single passage in support of your claim that it disproves the 'greenhouse effect'. So hey, allow me;

    In section 1.1 G&T assert that in determining whether CO2 is warming the planet we must look at two factors; thermal conductivity and isochoric thermal diffusivity... which are basically factors for determining the transfer of heat between molecules. What G&T leave out is that molecules can also be heated by electromagnetic radiation. In short, they start from a first principle of ignoring the central cause of greenhouse warming. Their claim would also mean that heat from the Sun only reaches Earth by being conducted from one molecule to the next... NOT in the form of EM radiation. Which is, of course, pure idiocy.

    That's page one. It goes downhill from there.
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  43. Tom Dayton
    Looked at your long list of refutations-two!
    The AP Smith one(above) and a German one that Eli Rabitt was going to use but since apparently has backed off)
    Interestingly at the end of the blog Eli asks for help from someone who knows some Physics

    ..Eli thinks it good that anyone writing on climate understand basic thermo. Other than that a passing acquaintance with the data and the basics helps a heap...
    You seem to have looked at the AP Smith website, what a howling mistake he makes about gases in a gravitational field!
    At first I thought it was a hasty slip up but he seems to be persisting in it.
    If you have any basic knowledge of Physics you will know its embarrassing.
    Further you state...
    "This is really graduate level climatology."
    Perhaps they should teach more Physics in the climatology classes and elementary mistakes will be reduced.
    I would recommend anyone with an interest in this topic to read the A P Smith blog as the arguments are teased out and positions clarified.
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  44. suibhne,
    you're actually missing that many climatologists have a PhD in Physics. You are also missing that one needs to know, for example, atmospheric physics as well.

    As i'm sure you may notice, i've actually read several opinion including Staples's and commented on the physics behind it. For this discussion to go anywhere you need to deal with the actual physics involved, not just use this sort of propaganda-based claims like "climatologists need to study physics".
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  45. CBDunkerson
    You imply by saying
    ... we must look at two factors; thermal conductivity and isochoric thermal diffusivity..that G&T do not deal with EM radiation.
    Most of their paper deals with em radiation!
    To selectively misquote and then prove a point will not further anyone's understanding.
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  46. Riccardo

    Point well made
    ..For this discussion to go anywhere you need to deal with the actual physics involved.

    I have to sign off as time presses.
    But what did you think of Smiths howler?- surely we can agree on that.
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  47. suibhne,
    i didn't reply to your accuse to Smith on the air molecule behaviour because it's irrelevant to our discussion.
    Not sure what you are quoting. I assume it was this:
    "Molecules don't know what the local temperature is, so "hot" molecules happily travel from cold regions to hot ones, and vice versa."

    If you have followed the whole reasoning, he was contrasting single molecule behaviour with macroscopic "averages". In this sense, it's absolutely correct and does not violate any law of thermodynamics. Indeed, temperature itself is a thermodynamic quantity and can be properly defined only as an ensamble average.

    Let me quote from a good old book (Terrel L. Hill, "Statistical Thermodynamics", chapter 1, the very first paragraph):
    "The object of thermodynamics is to derive mathematical relations which connect different experimental properties of macroscopic systems in equilibrium - systems containing many molecules, of the order of, say, 10^20 or more. However useful, these interconnections of thermodynamics give us no information at all concerning the interpretation or explanation, on a molecular level, of the observed experimental properties."

    With this in mind, we can go one step further and easily see that there's no violation of any law of thermodynamics (as too often claimed in certain quarters) when a molecule radiate a photon toward a warm object simply because thermodynamics does not apply at the single molecule level. A molecule will not choose the direction of the emitted photon, it can not.

    Still, thermodynamics applies at the macroscopic level, or, in terms of statistical thermodynamics, to the ensamble averages of the mechanical or thermodynamic quantities. So it should come as no surprise that the net overall flux will always be in the right direction.
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  48. Suibhne, yes the G&T paper covers EM radiation (incorrectly) in subsequent sections. However, at the start they define a premise that rising CO2 can only be causing warming if it significantly changes the thermal conductivity of the atmosphere as a whole... and then go on for a few pages to show that it doesn't... but then no proponent of the greenhouse effect ever claimed it did because that's not how the greenhouse effect works and G&T are simply, in that section, ignoring radiation physics. In later sections, when they do discuss radiation, they incorrectly dismiss radiative transfer on the grounds that it doesn't conform to thermal conductivity... in essence repeating their original false premise.

    Again, show me something in their paper which proves that the greenhouse effect does not exist. You insist it is in there, but have repeatedly refused to cite it.
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  49. angliss: If you want a really simple way to show somebody that not everything is a perfect grey body: just ask them to look around the room. Some things appear red, some blue, some green, even though they're being illuminated by the same light source.

    If the absorptivity were always constant over wavelength, this wouldn't be possible. You'd just see different shades of grey.
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  50. The complete G&T09 comment sent to the journal that published it can be found here on top of the list:

    How G&T made it through peer-review is unclear. Perhaps something similar to the Soon-Baliunas piece.
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