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Thread: How much energy can carbon dioxide emit?

  1. #1 How much energy can carbon dioxide emit? 
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    Maybe someone here can help me settle a bet. What is the maximum amount of energy that a carbon dioxide molecule can emit in joules per second?

    Assume it has come into contact with 10,000 nm of IR radiation, at 7.13 X 10^-17 Watts.

    Thanks in advance.


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    From chemical reactions in the atmosphere: 0. It's basically inert.

    From being the medium on which a heat engine is extracting energy: depends.

    From other chemical reactions: It depends. I think it would probably release energy if you mixed it with flourine. Because, well, pretty much everything does.

    But generally speaking it takes energy to turn CO2 into something else. It's not a process which gives off energy.


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  4. #3  
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    none , it just sits there.
    what do you mean by emit?
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    Quote Originally Posted by fizzlooney
    none , it just sits there.
    what do you mean by emit?
    That would be an example of how little energy it can emit. I am trying to find out the maximum. Can you think of a situation where CO2 absorbed IR and emitted energy, heat, radiation or...? In that situation, how much was emitted?
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  6. #5  
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    It all depends on how much energy it absorbed. It doesn't produce anything beyond what it absorbs. quite the contrary, it takes energy LOSS to get anything out of at all
    Wise men speak because they have something to say; Fools, because they have to say something.
    -Plato

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  7. #6 Re: How much energy can carbon dioxide emit? 
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    Quote Originally Posted by williampinn
    Maybe someone here can help me settle a bet. What is the maximum amount of energy that a carbon dioxide molecule can emit in joules per second?

    Thanks in advance.


    P.S. Assume the CO2 molecule has absorbed the maximum amount of IR radiation it can.
    If you mean vibrational energy, it would be about equal to the standard enthalpy of formation for CO2 plus the standard enthalpy of formation for oxygen and carbon - that would approximate the energy if each bond was stretched to near its breaking point, and then it relaxed, releasing the energy.

    If you include the energy associated with electrons moving from high excited-state energy levels near the limit of them not actually attached to the atoms any more, which are then allowed to drop back to their lower "core" energy levels, then the energy involved could be very high; probably in the xray or UV range for each of the 32 electrons in the molecule.

    If you combine the two, you would get the approximate energy of a cloud of two separate oxygen nuclei, a carbon nucleus, and 32 free electrons combining to form a CO2 molecule. That would be about the limit of the maximum theoretical energy you could pump into a CO2 molecule without completely blowing it apart (although in practice I suspect this would be almost impossible to do, since you would probably end up just blowing off some electrons and not exciting others at all if you tried to pump that much energy into it).

    But that just gets you the total energy. As for how quickly it could be released, I don't really know. I imagine the total power in watts would be quite high, since you're talking about releasing a lot of xray and UV photons in a pretty short time (I would guestimate microseconds, but I don't really know).

    Edit: upon further consideration, I guess you could also store energy in a CO2 molecule by compressing the bonds between the carbon and oxygen, which would probably let you store way more energy than by stretching them. I guess the limit in that case would be close to about twice the energy barrier for making a carbon nucleus fuse with an oxygen nucleus.
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    SAy WHAT?????????????
    fuse nuclei???????
    Here we go again.
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    It's a pointless question, since you could keep heating it forever and it would keep giving out energy.
    "The major difference between a thing that might go wrong and a thing that cannot possibly go wrong is that when a thing that cannot possibly go wrong goes wrong it usually turns out to be impossible to get at or repair." ~ Douglas Adams
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    Quote Originally Posted by drowsy turtle
    It's a pointless question, since you could keep heating it forever and it would keep giving out energy.
    I assumed he meant how much energy could you cram into it, and then have it re-release after you stopped adding energy. Although he seemed to want to know the power, not just the energy, and while you can probably figure out how much energy a CO2 molecule might theoretically store, I don't know how you could calculate how quickly it might be released.
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    Quote Originally Posted by drowsy turtle
    It's a pointless question, since you could keep heating it forever and it would keep giving out energy.
    Well the question asks how much energy it gives out per second, so if you keep heating it, how many Watts or joules per second would it emit?
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    Quote Originally Posted by Scifor Refugee
    Quote Originally Posted by drowsy turtle
    It's a pointless question, since you could keep heating it forever and it would keep giving out energy.
    I assumed he meant how much energy could you cram into it, and then have it re-release after you stopped adding energy. Although he seemed to want to know the power, not just the energy, and while you can probably figure out how much energy a CO2 molecule might theoretically store, I don't know how you could calculate how quickly it might be released.
    There must be a way. The greenhouse theory depends on it. Somehow the CO2 molecule absorbs and emits energy, but I'll be darned if I can get any specific numbers per molecule. Every source I have researched only discusses the issue in the most general terms.
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    LOL!
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    There is no constant value.

    All of the energy absorbed is re-emitted, although not necessarily as photons with the same wavelength.

    So the energy emitted depends on the energy absorbed to start with.

    So, day and night, and season, will affect this value, as well as height in the atmosphere, maybe.

    The point with global warming is not that it emits radiation, but more that it absorbs photons of a certain wavelength that would otherwise escape the atmosphere, keeping aditional heat trapped in the atmosphere instead of being radiated into space.

    So this hypothetical value for the energy emitted by a molecule of carbon dioxide is not really relevant to the theory.

    Understand?

    If not, sorry, I'm bad at explaining.
    "The major difference between a thing that might go wrong and a thing that cannot possibly go wrong is that when a thing that cannot possibly go wrong goes wrong it usually turns out to be impossible to get at or repair." ~ Douglas Adams
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    My understanding of climate science is that an exact value has been hard to reach. But I'm guessing you can probably extrapolate some reasonable bounds on it if you can't find any data online. Take Venus. Calculate the mass of CO2 in some given square footage of air column from the surface to infinity. Calculate the solar flux on its surface. Take its average temperature. Do the same to Earth. Compare the data you collected, assuming a linear relationship, and assuming that CO2 is the only greenhouse gas, and see what you get.
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    I would do it by measuring the amount of radiation leaveing the surface compared to the amount detected from orbit. Then calculate the power per molecule by calculation, using the PPM of carbon dioxide, and pressure in different parts of the atmosphere.
    "The major difference between a thing that might go wrong and a thing that cannot possibly go wrong is that when a thing that cannot possibly go wrong goes wrong it usually turns out to be impossible to get at or repair." ~ Douglas Adams
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    Quote Originally Posted by drowsy turtle
    There is no constant value.

    All of the energy absorbed is re-emitted, although not necessarily as photons with the same wavelength.

    So the energy emitted depends on the energy absorbed to start with.

    So, day and night, and season, will affect this value, as well as height in the atmosphere, maybe.

    The point with global warming is not that it emits radiation, but more that it absorbs photons of a certain wavelength that would otherwise escape the atmosphere, keeping aditional heat trapped in the atmosphere instead of being radiated into space.

    So this hypothetical value for the energy emitted by a molecule of carbon dioxide is not really relevant to the theory.

    Understand?

    If not, sorry, I'm bad at explaining.
    Thanks for clearing that up, so how much of that IR can the CO2 molecule absorb? Do any experiments set any records?
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    I would do it by measuring the amount of radiation leaveing the surface compared to the amount detected from orbit. Then calculate the power per molecule by calculation, using the PPM of carbon dioxide, and pressure in different parts of the atmosphere.
    Hmm, that probably makes more sense. Less susceptible to error. The absolute magnitude of Venus should be something you can look up. And then from that you can calculate a flux coming off the planet (maybe there's a formula somewhere?).

    There wouldn't happen to be a calculation of the mass of the atmosphere of Venus and Earth anywhere, is there?

    ...

    All that said, it's a very rough approximation. The hard part I think is determining what the temperature would have been without any greenhouse effect. Because the greenhouse effect is basically an albedo term for lower frequencies. Meaning that everything in an atmosphere has some effect on the "greenhouse effect" just from its absorption/transparency/reflection of different colors of light.

    CO2 is transparent to visible light and more opaque to infrared(? Or is it even lower frequencies of light?), so it lets the majority of the solar flux (which is centered at visible light) in. And then that flux heats the ground or water, and that ground and water release lower frequency light back out from its black body radiation. And CO2 absorbs some of that reflected light, heats up, and releases even lower frequencies back to the ground or into space.

    So the final temperature is a steady state involving the black body radiation of the planet coupled with the fact that a planet isn't a perfect black body and has all sorts of albedo terms from clouds and the ground, and the ground itself isn't homogeneous and has all sorts of its own albedo terms. And these terms are temperature dependent. Solid rock has a different albedo from magma, for instance.

    So a real term is understandably difficult to arrive at.
    "A witty saying proves nothing." - Voltaire
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    Quote Originally Posted by Numsgil
    My understanding of climate science is that an exact value has been hard to reach. But I'm guessing you can probably extrapolate some reasonable bounds on it if you can't find any data online. Take Venus. Calculate the mass of CO2 in some given square footage of air column from the surface to infinity. Calculate the solar flux on its surface. Take its average temperature. Do the same to Earth. Compare the data you collected, assuming a linear relationship, and assuming that CO2 is the only greenhouse gas, and see what you get.
    Thanks, I tried that with Mars and Earth. Mars being 90% CO2 atmosphere. The problem is Earth has oceans and more atmospheric pressure. Venus has SO2 in its atmosphere in large quantities, so it is like comparing apples and oranges.

    I even tried looking up the emissivity of CO2. The answers on that are all over the place. If you know of a reliable source, let me know.
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    Quote Originally Posted by Numsgil
    There wouldn't happen to be a calculation of the mass of the atmosphere of Venus and Earth anywhere, is there?
    http://en.wikipedia.org/wiki/Earth
    Earth's surface= 5.10072X10^8 km≤ * 1.0 X 10^6 m^2/km^2 = 5.10072 X 10^14 m^2


    P = F/A (P=Pressure, F=mg, A=area)
    Pacals = 1 N/m^2

    P=pgh(p=density,g=gravity,h=height)
    1atm = 1.013 X 10^5 Pa

    h = P/pg
    h = 1.013X10^5 Pa/9.81 * 1.2kg/m^3 =8605 m

    Total weight of air = 1.013 X 10^5 N/m^2 * 5.10072 X 10^14 m^2 (surface area)= 5.16192864 X 10^19 N

    Total mass of air = 5.16192864 X 10^19/9.81m/s^2 = 5.26190483 X 10^18 kg
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    Quote Originally Posted by Numsgil
    I would do it by measuring the amount of radiation leaveing the surface compared to the amount detected from orbit. Then calculate the power per molecule by calculation, using the PPM of carbon dioxide, and pressure in different parts of the atmosphere.
    Hmm, that probably makes more sense. Less susceptible to error. The absolute magnitude of Venus should be something you can look up. And then from that you can calculate a flux coming off the planet (maybe there's a formula somewhere?).

    There wouldn't happen to be a calculation of the mass of the atmosphere of Venus and Earth anywhere, is there?

    ...

    All that said, it's a very rough approximation. The hard part I think is determining what the temperature would have been without any greenhouse effect. Because the greenhouse effect is basically an albedo term for lower frequencies. Meaning that everything in an atmosphere has some effect on the "greenhouse effect" just from its absorption/transparency/reflection of different colors of light.

    CO2 is transparent to visible light and more opaque to infrared(? Or is it even lower frequencies of light?), so it lets the majority of the solar flux (which is centered at visible light) in. And then that flux heats the ground or water, and that ground and water release lower frequency light back out from its black body radiation. And CO2 absorbs some of that reflected light, heats up, and releases even lower frequencies back to the ground or into space.

    So the final temperature is a steady state involving the black body radiation of the planet coupled with the fact that a planet isn't a perfect black body and has all sorts of albedo terms from clouds and the ground, and the ground itself isn't homogeneous and has all sorts of its own albedo terms. And these terms are temperature dependent. Solid rock has a different albedo from magma, for instance.

    So a real term is understandably difficult to arrive at.
    Venus has too many unknown variables. It is hard to get a before and after Vernus to make an apples to apples comparison. If I just had some specific info on CO2 I could calculate the the impact of any atmospheric concentration of the gas using Stephen-Boltzman equation and cross check with some other therm equations.
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    Quote Originally Posted by drowsy turtle
    It's a pointless question, since you could keep heating it forever and it would keep giving out energy.
    Pretty much. It will emit about the same as it's receiving assuming it's in equilibrium. If it's receiving more it will heat and emit more until it's again in equilibrium. The upper limit would be set by more by the strength of the molecule bonds than anything else.

    Those limits would have almost nothing to do with its how much energy Co2 absorbs and re emits in the atmosphere, where other molecules overlap its emission bands and by collisions and other processes distribute its temperature.
    --

    Mars has about a 5C green house effect from its 90+% CO2 atmosphere.
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    Oooookay. CO2 absorbs best at around 4100 nm, which is about 4.8E-20 joules. If the excited state lifetime is 10 picoseconds (which I would guess is probably actually a bit long, but this whole thing is a guesstimate) then you could get around 4.8E-9 joules emitted per second. That would be about 7.22e16 watts per kg of CO2. But that calculation assumes that a new IR photon is present to immediately re-excite the CO2 molecule as soon as it relaxes. If your light source is the sun and the CO2 is floating around in the atmosphere, the actual power of the emitted radiation would surely be much much lower, since there will probably be a fairly long lag between each excitation/emission even.
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    Quote Originally Posted by Scifor Refugee
    Oooookay. CO2 absorbs best at around 4100 nm, which is about 4.8E-20 joules. If the excited state lifetime is 10 picoseconds (which I would guess is probably actually a bit long, but this whole thing is a guesstimate) then you could get around 4.8E-9 joules emitted per second. That would be about 7.22e16 watts per kg of CO2. But that calculation assumes that a new IR photon is present to immediately re-excite the CO2 molecule as soon as it relaxes. If your light source is the sun and the CO2 is floating around in the atmosphere, the actual power of the emitted radiation would surely be much much lower, since there will probably be a fairly long lag between each excitation/emission even.
    Thanks for those numbers. Do you know how well CO2 absorbs 9000-10000 nm? I think that range is closer to the Earth's temperature according to Wien's equation.
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    Quote Originally Posted by Lynx_Fox

    Mars has about a 5C green house effect from its 90+% CO2 atmosphere.
    With 600 Pa of pressure and IR emitted at around 14000 nm. Show me your math if you can. From what I understand, CO2 does not absorb 14000 nm.
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    Quote Originally Posted by williampinn
    Thanks for those numbers. Do you know how well CO2 absorbs 9000-10000 nm? I think that range is closer to the Earth's temperature according to Wien's equation.
    I take IR spectra of things all the time, and there are always big background peaks for CO2 around there (unless you're careful to purge the air from the spectrometer before you take the spectrum). I don't remember exactly where they are off hand, so that number might be a little bit off, but it should be fairly close.
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    Quote Originally Posted by Scifor Refugee
    Quote Originally Posted by williampinn
    Thanks for those numbers. Do you know how well CO2 absorbs 9000-10000 nm? I think that range is closer to the Earth's temperature according to Wien's equation.
    I take IR spectra of things all the time, and there are always big background peaks for CO2 around there (unless you're careful to purge the air from the spectrometer before you take the spectrum). I don't remember exactly where they are off hand, so that number might be a little bit off, but it should be fairly close.
    Thanks for your assistance. I can wrap this thing up if I have what constitutes the surface area of a CO2 molecule and its emissivity.
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    Quote Originally Posted by williampinn
    Quote Originally Posted by Lynx_Fox

    Mars has about a 5C green house effect from its 90+% CO2 atmosphere.
    With 600 Pa of pressure and IR emitted at around 14000 nm. Show me your math if you can. From what I understand, CO2 does not absorb 14000 nm.
    Of course it does, it absorbs at 2700, 4300 and a pretty wide band near 14000-1500 nm. These were observed more than a century ago, and can now be modeled but I'll let Scifor go deeper if he choices--he can probably explain the vibrational modes better than I can.

    No single equation would work, it takes a radiative transfer model to show something like you ask, but I'll see if I can find a simple 1-D model that works with Mars atmosphere.
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    You know, it's quite possible that we're approaching this question from the wrong direction. Knowing how much IR radiation a molecule of CO2 can transduce into heat probably helps, but in order to determine the effect of adding CO2 to the atmosphere, we've also got to determine how much the probability of any given IR photon hitting a CO2 atom has increased by adding more % CO2 composition.

    From what I can tell, the problem is IR photons that would normally miss all the CO2 molecules on their way out into space, start hitting them more often. (Because it's harder to miss if there are more of them). It may be that the majority of CO2 atoms are not coming anywhere near their maximum transducing capacity.
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  30. #29 Re: How much energy can carbon dioxide emit? 
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    Quote Originally Posted by williampinn
    Maybe someone here can help me settle a bet. What is the maximum amount of energy that a carbon dioxide molecule can emit in joules per second?

    Assume it has come into contact with 10,000 nm of IR radiation, at 7.13 X 10^-17 Watts.

    Thanks in advance.
    I saw your other interesting post about IR and CO2 so will answer both. NASA has done considerable modeling of the Venusian atmosphere based on the returns from
    from a number of probes, going back to the first Russian lander. Venus of course
    has the highest concentration of CO2 in its atmosphere vs. all other planets
    combined. (Earth is 2nd, Mars is 3rd and the only CO2 bearing atmospheres in
    our solar system). You might go to the NASA website and do a search for Venus
    data (I cant bring up one for you from the compuer Im using at the moment)
    but I know you will find something about CO2-IR interactivity through the NASA
    research archives, and probably something which overlaps with with Earth
    (Greenhouse effect) which seems to be the basis for your interest?

    I am sure you will find something of interest and relevant through a NASA search -

    good luck.
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  31. #30 Re: How much energy can carbon dioxide emit? 
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    Quote Originally Posted by georger
    Quote Originally Posted by williampinn
    Maybe someone here can help me settle a bet. What is the maximum amount of energy that a carbon dioxide molecule can emit in joules per second?

    Assume it has come into contact with 10,000 nm of IR radiation, at 7.13 X 10^-17 Watts.

    Thanks in advance.
    I saw your other interesting post about IR and CO2 so will answer both. NASA has done considerable modeling of the Venusian atmosphere based on the returns from
    from a number of probes, going back to the first Russian lander. Venus of course
    has the highest concentration of CO2 in its atmosphere vs. all other planets
    combined. (Earth is 2nd, Mars is 3rd and the only CO2 bearing atmospheres in
    our solar system). You might go to the NASA website and do a search for Venus
    data (I cant bring up one for you from the compuer Im using at the moment)
    but I know you will find something about CO2-IR interactivity through the NASA
    research archives, and probably something which overlaps with with Earth
    (Greenhouse effect) which seems to be the basis for your interest?

    I am sure you will find something of interest and relevant through a NASA search -

    good luck.
    Thanks I'll look into that.
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    Quote Originally Posted by kojax
    You know, it's quite possible that we're approaching this question from the wrong direction. Knowing how much IR radiation a molecule of CO2 can transduce into heat probably helps, but in order to determine the effect of adding CO2 to the atmosphere, we've also got to determine how much the probability of any given IR photon hitting a CO2 atom has increased by adding more % CO2 composition.

    From what I can tell, the problem is IR photons that would normally miss all the CO2 molecules on their way out into space, start hitting them more often. (Because it's harder to miss if there are more of them). It may be that the majority of CO2 atoms are not coming anywhere near their maximum transducing capacity.
    Using Stephen-Boltzman's equation I was able to calculate the power of IR coming from earth:
    emissivity = .9; surface area of earth = 5.10072 X 10^14; 5.67 X 10-8 = constant; Average Earth temperature = 287K.

    P = (.9)(5.10072 X 10^14)(5.67 X 10^-8)([287K]^4) = 1.766 X 10^17 W

    In another thread I calculated the probability of IR coming into contact with CO2:

    That probability, taking water vapor into account, is .012. Assuming CO2 is a perfect emitter, I assumed it would emit no more than .012 the energy it receives from Earth, and half of the energy emited at 12 o'clock would be lost. Thus the total energy available if the atmospheric CO2 is doubled is:

    Total P = (1.766 + .0106) X 10^17 = 1.7766 X 10^17

    With this total power figure, we now calculate how much doubling CO2 concetration will have on the temperature:

    T = [(1.7766 X 10^17 W)/(.9)(5.1 X 10^14)(5.67 X 10^-.8)]^1/4 = (68.3 X 10^8)^1/4
    = 2.87 X 10^2 = 287K

    The impact is nil. I read that the emissivity of CO2 is only 0.00092. If that figure is correct, then CO2's impact is even less than nil.

    Interestingly, to get any noticible increase in temperature I had to increase CO2's concentration tenfold:

    Apparently the Earth has a built in thermostat. The more energy that is trapped or added the less impact it has. If the Stephen-Boltzman law of physics iis true then positive feedbacks, and runaway temperatures are a myth.
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    Quote Originally Posted by williampinn
    Apparently the Earth has a built in thermostat. The more energy that is trapped or added the less impact it has. If the Stephen-Boltzman law of physics iis true then positive feedbacks, and runaway temperatures are a myth.
    I didn't follow all of your math. But you'll need more significant digits, and then back it up with some experimental data, before you can call the prevailing scientific theory a myth. At this stage the proper reaction is "huh, that's funny..."

    Likewise, what are you taking aim at? That CO2 causes warming? That anthropogenic additions of CO2 cause warming? That the green house effect is even a real effect?

    And you'll also need to provide a framework which can more or less accurately predict the temperature of Venus, since Venus is used as a "greenhouse effect gone wild" model.
    "A witty saying proves nothing." - Voltaire
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    The effect is cumulative; the point is there is slightly more energy remaining in the atmosphere than leaving it.

    However, as you correctly stated, a hotter atmosphere will tend to emit more energy, thereby decreasing the extent of heating in the atmosphere.

    This is why I tend to ignore various attempts to sell global warming to me. Especially since if you calculate the heat released from the global burning of fossil fuels, it more than accounts for the heating effect observed over the past decade. Not to mention other fuels, such as biofuels and wood.

    Although, this doesn't really change much in the way of finding new energy sources, because you would still ideally need renewable energy sources which do not produce heat.

    This rules out nuclear, too.
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    Although I have not personally examined the relevant research papers and scrutinized the math, it seems very, very unlikely to me that the relevant experts would just pull something like CO2's impact on global temperatures out of their asses without actually checking the math to see if it makes sense.

    If a group of experts whose full-time job is modeling the climate say one thing, and some back-of-the-envelope calculation based on hasty approximations say something else, I know who I'll be betting on...
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    Quote Originally Posted by Numsgil

    I didn't follow all of your math.
    That is unfortunate.

    Quote Originally Posted by Numsgil
    But you'll need more significant digits, and then back it up with some experimental data, before you can call the prevailing scientific theory a myth.
    Just because Al Gore said in his movie it is the prevailing theory does not make it so. The Stephen-Boltzman law of physics is a REAL prevailing theory. The anthropogenic warming hypothesis is falsified by it. The burden of proof is on you to show that the Stephen-Boltzman law is wrong, because if it isn't wrong, your pet theory with all its media hype, can't be right.

    Quote Originally Posted by Numsgil
    At this stage the proper reaction is "huh, that's funny..."
    Or you could take it upon yourself to learn a little math and physics so you can do your own critical examination.
    Quote Originally Posted by Numsgil
    Likewise, what are you taking aim at? That CO2 causes warming? That anthropogenic additions of CO2 cause warming? That the green house effect is even a real effect?
    All of the above you mentioned is true. What the equation shows is that the impact is practically nil. Imagine trying to boil a pot of water with a match. Certainly the match does what every scientist says it will do, and so does the water, but you won't come close to bringing the water to a boil.
    Quote Originally Posted by Numsgil
    And you'll also need to provide a framework which can more or less accurately predict the temperature of Venus, since Venus is used as a "greenhouse effect gone wild" model.
    Stephen-Boltzman has already done the work. You can predict the absolute temperature of anything if you know the power in watts, the emissivity and surface area of what you are examining. Even Venus did not go wild. That is hype and "wild" is a subjective term.
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    Quote Originally Posted by Scifor Refugee
    Although I have not personally examined the relevant research papers and scrutinized the math, it seems very, very unlikely to me that the relevant experts would just pull something like CO2's impact on global temperatures out of their asses without actually checking the math to see if it makes sense.

    If a group of experts whose full-time job is modeling the climate say one thing, and some back-of-the-envelope calculation based on hasty approximations say something else, I know who I'll be betting on...
    Before you make that bet, feel free to check my math and to look into the Stephen-Boltzman law of physics. Also keep in mind that there was a strong consensus during the Y2K scare. I bet I know which way you bet on that one, so I have two questions for you:
    1. How much did you pay for your Y2K survival kit?
    2. How did it work out for you?

    Always think things through carefully before gambling your hard-earned money. :-D
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    Quote Originally Posted by drowsy turtle
    The effect is cumulative; the point is there is slightly more energy remaining in the atmosphere than leaving it.

    However, as you correctly stated, a hotter atmosphere will tend to emit more energy, thereby decreasing the extent of heating in the atmosphere.
    Thank you for comment. You seem to know how things work in the real world.
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    Something one of my professors just happened to mention in class last week comes to mind. He mentioned that the water in the air, or humidity actually has a much stronger green house effect than the CO2. I don't remember what figure he cited, but it was pretty ridiculous how much stronger the effect was. (It's actually a class on alternative energy, interestingly enough)

    The specific emissivity of CO2 itself might not be all that's at stake here, however. It could have to do with the molecule's interaction with other molecules/elements as well. If, for example, the greater amount of CO2 leads more water to evaporate, then we might have a bigger problem. (Not that I'm saying it does, just pointing out that there might be more stones we ought to turn over, before drawing a final conclusion.)




    Quote Originally Posted by drowsy turtle
    The effect is cumulative; the point is there is slightly more energy remaining in the atmosphere than leaving it.

    However, as you correctly stated, a hotter atmosphere will tend to emit more energy, thereby decreasing the extent of heating in the atmosphere.

    This is why I tend to ignore various attempts to sell global warming to me. Especially since if you calculate the heat released from the global burning of fossil fuels, it more than accounts for the heating effect observed over the past decade. Not to mention other fuels, such as biofuels and wood.

    Although, this doesn't really change much in the way of finding new energy sources, because you would still ideally need renewable energy sources which do not produce heat.

    This rules out nuclear, too.
    I think, if I look back into my notes, there might be numbers for that, and the impact might actually be substantial enough to matter. However I'm too tired to want to get out my school materials right now.

    I think he told us at some point how much energy from the sun hits us everyday, and what world wide power consumption is. That should be enough to go on, probably, because ultimately all the energy in our power grids, and automobiles, and such, becomes heat.
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    Quote Originally Posted by williampinn
    Quote Originally Posted by Numsgil

    I didn't follow all of your math.
    That is unfortunate.
    I have a short attention span. and 8) smileys don't help.

    Condense it down into a concise and neat form, and use latex. "If your ideas are that
    good, you'll have to ram them down people's throats." - Howard Aiken.
    "A witty saying proves nothing." - Voltaire
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    Quote Originally Posted by kojax
    there might be more stones we ought to turn over, before drawing a final conclusion.)
    This stone was turned over long ago. Water vapor is about five times as prevalent in the atmosphere as CO2 and has about twice the greenhouse effect, but water increases in response to increased CO2. It is therefore a feedback and not the forcing agent. You can read about it here:

    http://www.realclimate.org/index.php...ck-or-forcing/
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    Quote Originally Posted by williampinn
    Before you make that bet, feel free to check my math and to look into the Stephen-Boltzman law of physics.
    Yeah, I know about the boltzman law, and I'm quite certain that professional climate modelers do too. Like I said, it seems very, very unlikely to me that CO2's impact on global climates was simply concocted and thrown out there without the professionals checking the math. That sort of thing just doesn't happen in the physics community. And even if someone did throw it out without checking the math, it would take about 15 seconds for a small army of physicists to realize the problem and publish their own analysis in journals.

    If a bunch of guys with PhDs in a subject all think one thing, and you (or I) think something else, then the problem is almost certainly with you (unless you also have a PhD in the relevant subject).
    Also keep in mind that there was a strong consensus during the Y2K scare.
    No, there wasn't. Anyone who actually had a clue about the situation knew that it wasn't going to cause major problems. There were, however, a ton of attention-seeking nuts who made a lot of noise about it.
    I bet I know which way you bet on that one, so I have two questions for you:
    1. How much did you pay for your Y2K survival kit?
    I put zero money or effort into preparing for the Y2K bug, because I listened to the experts.
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    Quote Originally Posted by kojax
    Something one of my professors just happened to mention in class last week comes to mind. He mentioned that the water in the air, or humidity actually has a much stronger green house effect than the CO2. I don't remember what figure he cited, but it was pretty ridiculous how much stronger the effect was. (It's actually a class on alternative energy, interestingly enough)

    The specific emissivity of CO2 itself might not be all that's at stake here, however. It could have to do with the molecule's interaction with other molecules/elements as well. If, for example, the greater amount of CO2 leads more water to evaporate, then we might have a bigger problem. (Not that I'm saying it does, just pointing out that there might be more stones we ought to turn over, before drawing a final conclusion.)
    I have read about this hypothesis. However, no one who proffers it can yet explain how it is supposed to work. How, for example, can CO2 get around the laws of thermal transfer, or conservation of energy? Any added energy or saved energy will add more heat to a system and cause a few more water molecules to evaporate, but the impact gets smaller and smaller as time progresses, and the impact is so very small to begin with. Water vapor has far more bandwidth than CO2, so one has to wonder why water can't bring itself to a boil. Apparently there is something in the physics that prevents that positive feedback loop: the Stephen-Boltzman law.
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    Quote Originally Posted by williampinn
    Apparently there is something in the physics that prevents that positive feedback loop: the Stephen-Boltzman law.
    More to do with most water vapor being precipitated out in a few days which sets a limit in the total water vapor balanced by the surface temperature based rate of evaporation. In theory, only if the surface got warm enough to boil would it completely saturate the atmosphere; that condition is commonly called run away green house conditions. Some think that's what happened on early Venus. The sun just isn't bright enough in Earth's orbit to create this condition.
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    Quote Originally Posted by Scifor Refugee
    Yeah, I know about the boltzman law, and I'm quite certain that professional climate modelers do too.
    One climate model I checked does not even address that law.
    http://www.atmos.washington.edu/hono...tructions.html

    Can you show me one that does?

    Quote Originally Posted by Scifor Refugee
    Like I said, it seems very, very unlikely to me that CO2's impact on global climates was simply concocted and thrown out there without the professionals checking the math.
    I am sure they checked the math they had, but that does not mean it was complete. Their predictions in the past were pretty outlandish, and of course, did not come true, even with all the math checking.

    Quote Originally Posted by Scifor Refugee
    That sort of thing just doesn't happen in the physics community. And even if someone did throw it out without checking the math, it would take about 15 seconds for a small army of physicists to realize the problem and publish their own analysis in journals.
    Only 15 seconds? Where did you get that number? Did you check your math? I think you just gave an example of what can happen with numbers. You, for one, take the system for granted, so you would definitely NOT be among those who would check or test the proposal in 15 seconds. Perhaps you are not alone.

    Quote Originally Posted by Scifor Refugee
    If a bunch of guys with PhDs in a subject all think one thing, and you (or I) think something else, then the problem is almost certainly with you (unless you also have a PhD in the relevant subject).
    LOL! Well Columbus did not have a PhD, so he was wrong about the Earth's shape. Faraday was a bookbinder (no PhD), so he was wrong about electromagnetism. Einstein was a patent clerk (no PhD) so his theories must be wrong. The Wright brothers were bicycle mechanics, I believe, definitely not PhDs. So they did not invent the airplane. Henry Ford did not have a PhD. Thomas Edison--no PhD. Steve Jobs and Steve Wasniac of Apple Computer did not even finish college when they invented the Mac computer. Steve McKentyre is an amateur scientist who busted NASA's climate data recently. Apparently all those PhDs at NASA overlooked the fact that 1998 was not the hottest year on record. Is this list long enough? Or do you need more examples?

    One thing I like about America is the freedom to put ideas across, whether those ideas come from a PhD or a couple of bike mechanics working out of their barn.
    I think the best way to tell a good idea from a bad one is to put it to the test yourself.

    Quote Originally Posted by Scifor Refugee
    Also keep in mind that there was a strong consensus during the Y2K scare.
    No, there wasn't. Anyone who actually had a clue about the situation knew that it wasn't going to cause major problems.
    LOL! Oh really? Which PhDs came forward prior to midnight 2000, and told us it was not going to cause major problems? You must have a list. Please share it with us.

    Quote Originally Posted by Scifor Refugee
    There were, however, a ton of attention-seeking nuts who made a lot of noise about it.
    And you don't think there are attention-seeking nuts today (with PhDs) making noise about...eh hem...climate change?

    Quote Originally Posted by Scifor Refugee
    I put zero money or effort into preparing for the Y2K bug, because I listened to the experts.
    And their names were..................(fill in the blank)...........


    One question you might ask yourself is, if current climate science is legit science, then why is it so political? Legit science has no need for politics. It is simply an investigation into the truth. The desire for carbon taxes can certainly put a damper on pure science. Notice how this topic always turns into a political debate. Where is the science now? Out the window! I came here to find out what CO2 can actually do, and so far I have learned precious little. I want to find out if it does what they say it does and to what extent. If the science is real and pure, then describing CO2's specific properties should not be a problem. Describing how it overcomes Stephen-Bolzman's equation should not be a problem either. I should learn something more than "Well all the experts say CO2 is bad for the planet." Am I getting through to you even a tiny bit?
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    Quote Originally Posted by kojax
    Quote Originally Posted by drowsy turtle
    The effect is cumulative; the point is there is slightly more energy remaining in the atmosphere than leaving it.

    However, as you correctly stated, a hotter atmosphere will tend to emit more energy, thereby decreasing the extent of heating in the atmosphere.

    This is why I tend to ignore various attempts to sell global warming to me. Especially since if you calculate the heat released from the global burning of fossil fuels, it more than accounts for the heating effect observed over the past decade. Not to mention other fuels, such as biofuels and wood.

    Although, this doesn't really change much in the way of finding new energy sources, because you would still ideally need renewable energy sources which do not produce heat.

    This rules out nuclear, too.
    I think, if I look back into my notes, there might be numbers for that, and the impact might actually be substantial enough to matter. However I'm too tired to want to get out my school materials right now.
    I have calculated an approximate value myself, about a year ago. I found that the expected increase would be about +0.06K per year.

    The measured temperature increase over the last 5 years averages about +0.02K per year.

    Quote Originally Posted by kojax
    I think he told us at some point how much energy from the sun hits us everyday, and what world wide power consumption is. That should be enough to go on, probably, because ultimately all the energy in our power grids, and automobiles, and such, becomes heat.
    True. I didn't have access to these figures when I calculated my value. As I say, I only applied this theory for fossil fuels, although admittedly I failed to account for increased emission into space or water/ground absorbtion.
    "The major difference between a thing that might go wrong and a thing that cannot possibly go wrong is that when a thing that cannot possibly go wrong goes wrong it usually turns out to be impossible to get at or repair." ~ Douglas Adams
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    Quote Originally Posted by Bunbury
    Quote Originally Posted by kojax
    there might be more stones we ought to turn over, before drawing a final conclusion.)
    This stone was turned over long ago. Water vapor is about five times as prevalent in the atmosphere as CO2 and has about twice the greenhouse effect, but water increases in response to increased CO2. It is therefore a feedback and not the forcing agent. You can read about it here:

    http://www.realclimate.org/index.php...ck-or-forcing/
    Here's the part that was interesting to me:

    Quote Originally Posted by The Article
    When surface temperatures change (whether from CO2 or solar forcing or volcanos etc.), you can therefore expect water vapour to adjust quickly to reflect that. To first approximation, the water vapour adjusts to maintain constant relative humidity. It's important to point out that this is a result of the models, not a built-in assumption. Since approximately constant relative humidity implies an increase in specific humidity for an increase in air temperatures, the total amount of water vapour will increase adding to the greenhouse trapping of long-wave radiation. This is the famed 'water vapour feedback'. A closer look reveals that for a warming (in the GISS model at least) relative humidity increases slightly in the tropics, and decreases at mid latitudes.
    This goes back to Drowsy Turtle's suggestion:

    Quote Originally Posted by drowsy turtle
    The effect is cumulative; the point is there is slightly more energy remaining in the atmosphere than leaving it.

    However, as you correctly stated, a hotter atmosphere will tend to emit more energy, thereby decreasing the extent of heating in the atmosphere.

    This is why I tend to ignore various attempts to sell global warming to me. Especially since if you calculate the heat released from the global burning of fossil fuels, it more than accounts for the heating effect observed over the past decade. Not to mention other fuels, such as biofuels and wood.

    Although, this doesn't really change much in the way of finding new energy sources, because you would still ideally need renewable energy sources which do not produce heat.

    This rules out nuclear, too.
    It seems that we could ignore CO2 specifically as the source of global warming, and it still wouldn't change the reality of the effect.

    If water vapor really is a feedback effect, and we've been directly warming our own atmosphere, then there's going to be more water vapor up there, which will warm things up even more, which will cause more water to evaporate, which will warm things up even more.....

    It could become quite a loop. However, it is starting to look possible that CO2 is just a minor player. One question is still left for me, however:

    Does water have a stronger tendency to remain in gaseous form when it's in atmospheres of different chemical compositions? If we add more CO2 to the atmosphere, are there any specifically chemical reactions involved that increase or decrease the likelihood of that water precipitating?
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    Quote Originally Posted by Lynx_Fox
    In theory, only if the surface got warm enough to boil would it completely saturate the atmosphere; that condition is commonly called run away green house conditions. Some think that's what happened on early Venus. The sun just isn't bright enough in Earth's orbit to create this condition.
    I have a lot of questions for those who think they know what happened on Venus. I don't see how water vapor can cause a runaway effect. It is lighter than air, so it rises to the atmosphere where it is cooler due to lower atmospheric pressure. It then forms clouds and condences. More clouds block more sunlight from reaching the earth. It looks like a negative feedback, not a positive one. Of course, you can't have more water vapor to begin with if you don't have more energy. The Stephan-Botzman equation shows that for every time you increase the energy, the resulting temperature is the fourth root of that energy. The more energy you add or save, the less and less impact it has, so the less and less water vapor you will have to begin with.

    I think if you read the fine print, you find disclaimers from those who think they know what happened to Venus.
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    Quote Originally Posted by williampinn
    Can you show me one that does?
    Not off hand, no, but then again I haven't really looked. It would probably take me days of study just to understand what they hell they're talking about.
    I am sure they checked the math they had, but that does not mean it was complete.
    The Boltzmann law is not the sort of thing one is likely to forget to consider.
    Only 15 seconds? Where did you get that number? Did you check your math? I think you just gave an example of what can happen with numbers.
    For god's sake, I didn't think you would have such a problem recognizing hyperbole. Yeah, if you want to be painfully literal about it, it would probably be a month or two at least between when something was published in a journal and someone publishing a response.
    You, for one, take the system for granted, so you would definitely NOT be among those who would check or test the proposal in 15 seconds. Perhaps you are not alone.
    Yeah, I'm a chemist, not a physicist or climatologist, so I don't spend any sort of serious time checking the details of people's work in climate modeling. If it were chemistry, and it was in an area I cared about, then I would check it. Of course I am not alone in this - there are probably only a few thousand people in the world who are really qualified to understand and evaluate these sorts of climate models.

    What I do take for granted is that there are smart, serious people with a thorough understanding of the relevant math and physics who check this sort of stuff, and that the odds of any amateur in a forum like this uncovering a serious problem with their work that has eluded the professional community is close to zero.
    LOL! Well Columbus did not have a PhD, so he was wrong about the Earth's shape.
    WTF does Columbus have to do with modern science? And he's a really shitty example for you to try to use, because he WAS wrong. What people disagreed with about Columbus was the earth's size; everyone who had a clue knew that the earth was too big for a ship to sail around the world from Europe to India, while Columbus thought that it was small enough for it to be possible. Of course, he was wrong and the experts were correct - if an entire continent that no one knew about hadn't been in the way, his entire crew would have died long before reaching India.
    Faraday was a bookbinder (no PhD), so he was wrong about electromagnetism.
    Faraday worked at the dawn of modern science, back when there were only "natural philosophers" rather than scientists. Things are pretty different now.
    Einstein was a patent clerk (no PhD) so his theories must be wrong.
    Einstein got a PhD in theoretical physics the same year his theories were published. Most of his work was part of his dissertation.
    The Wright brothers were bicycle mechanics, I believe, definitely not PhDs. So they did not invent the airplane.
    Not relevant at all, because so far as I know no scientists of the time ever claimed powered flight was impossible.

    (rest of rant snipped)

    Look, I'm not going to argue with you, because I don't really care. If you want to continue to believe that you're going to poke holes in the work of professionals, hey, knock yourself out. I wish you the best of luck.
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    Quote Originally Posted by kojax
    It seems that we could ignore CO2 specifically as the source of global warming, and it still wouldn't change the reality of the effect.

    If water vapor really is a feedback effect, and we've been directly warming our own atmosphere, then there's going to be more water vapor up there, which will warm things up even more, which will cause more water to evaporate, which will warm things up even more.....
    I see you are seeing the irony of it all. If there was anything to this feedback hypothesis, you should be able to perform the following experiment: Place some water in a sealed glass container. The greenhouse effect of the glass should warm up the water, causing water vapor. The water vapor should trap more heat and so on until the water reaches the boiling point.




    Quote Originally Posted by kojax
    It could become quite a loop. However, it is starting to look possible that CO2 is just a minor player.
    There is currently approximately 100 times as much water vapor as CO2 in the atmosphere.

    Quote Originally Posted by kojax
    One question is still left for me, however:

    Does water have a stronger tendency to remain in gaseous form when it's in atmospheres of different chemical compositions?
    No because the atmosphere is a mixture of air, not a composition of air molecules. The gases are pretty inert and don't react with each other.

    Quote Originally Posted by kojax
    If we add more CO2 to the atmosphere, are there any specifically chemical reactions involved that increase or decrease the likelihood of that water precipitating?
    CO2 is heavier than air, water vapor is lighter than air. one sinks the other rises to the upper atmosphere where it is cooler due to lower atmospheric pressure, then condences, additionally the clouds' albedo has a cooling effect.
    Check your carbonated beverages and see if they are warmer than non-carbonated beverages--all other variables being equal.
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    Quote Originally Posted by Scifor Refugee
    Quote Originally Posted by williampinn
    Can you show me one that does?
    Not off hand, no, but then again I haven't really looked. It would probably take me days of study just to understand what they hell they're talking about.
    So basically you can't be sure you know what you are talking about.


    Quote Originally Posted by Scifor Refugee
    The Boltzmann law is not the sort of thing one is likely to forget to consider.
    But I just got through showing you one climate model that did forget to consider it. You just got through NOT showing that there are any models that do. Does evidence or the the lack thereof matter to you?

    Quote Originally Posted by Scifor Refugee
    Yeah, I'm a chemist, not a physicist or climatologist, so I don't spend any sort of serious time checking the details of people's work in climate modeling. If it were chemistry, and it was in an area I cared about, then I would check it. Of course I am not alone in this - there are probably only a few thousand people in the world who are really qualified to understand and evaluate these sorts of climate models.
    And you know all of this because you know so little of climate models? I think you have also demonstrated the indifferent nature of the establisment. "That's not my field. Let someone else look into it." Under your world view, only astrologers can criticise and examine astrology.

    Quote Originally Posted by Scifor Refugee
    What I do take for granted is that there are smart, serious people with a thorough understanding of the relevant math and physics who check this sort of stuff
    Who exactly are they? You don't know because you take it for granted. But somehow you know in your heart they exist and they are checking. Somehow that does not seem very scientific.

    Quote Originally Posted by Scifor Refugee
    , and that the odds of any amateur in a forum like this uncovering a serious problem with their work that has eluded the professional community is close to zero.
    I guess the evidence does not matter to you. I gave you an example of a climate model that does not factor in Stephen-Boltzman. If the "professionals" really believe their own BS about a runaway greenhouse effect, then obviously none of them factored in the Stephan-Boltzman law. The two concepts are a complete contradiction. That brings the probability, not the odds, close to 100%, notwithstanding my amateur status.

    Quote Originally Posted by Scifor Refugee
    WTF does Columbus have to do with modern science?
    Probably nothing if modern science only listens to elitists and cares nothing about the evidence.


    Quote Originally Posted by Scifor Refugee
    And he's a really shitty example for you to try to use, because he WAS wrong. What people disagreed with about Columbus was the earth's size; everyone who had a clue knew that the earth was too big for a ship to sail around the world from Europe to India, while Columbus thought that it was small enough for it to be possible. Of course, he was wrong and the experts were correct -
    What experts were correct? Do you have any sources? If you are right, then my history teachers lied to me. By the way, they are experts on history and you're not, but don't let that stop you from expressing your views, because even a stopped clock can be right twice a day.


    Quote Originally Posted by Scifor Refugee
    Faraday worked at the dawn of modern science, back when there were only "natural philosophers" rather than scientists.
    You are obviously an amateur historian. Nothing wrong with that as long as you do your research, which you forgot to do:

    Scientists of the 1800s

    Michael Faraday
    William Harvey
    George Washington Carver
    James Clerk-Maxwell
    Alfred Wallace
    Enrico Fermi
    J.J. Thompson

    http://www.sbhsd.k12.ca.us/sbhslib/s...scientists.htm

    Quote Originally Posted by Scifor Refugee
    Einstein got a PhD in theoretical physics the same year his theories were published. Most of his work was part of his dissertation.
    LOL! Einstein worked in the patent office in Bern Switzerland. He wasn't even in school. I see you like to make up stuff as you go along. You would make a great modern scientist. Try Googling next time.

    Quote Originally Posted by Scifor Refugee
    The Wright brothers were bicycle mechanics, I believe, definitely not PhDs. So they did not invent the airplane.
    Not relevant at all, because so far as I know no scientists of the time ever claimed powered flight was impossible.
    But none of those expert scientists invented the airplane. That was the point. Just because you have a degree does not make you the end all and be all. I believe it was Einstein who said, "The only thing worse than ignorance is arrogance."


    Quote Originally Posted by Scifor Refugee
    Look, I'm not going to argue with you, because I don't really care. If you want to continue to believe that you're going to poke holes in the work of professionals, hey, knock yourself out. I wish you the best of luck.
    Thanks. I would strongly encourage you to poke holes in the work of professionals. It keeps them on their toes. If your financial expert robs you blind, feel free to poke holes in his ideas. If your phycician commits malpractice, feel free to poke holes in his ideas. If climatologist's doom-and-gloom predictions fail to come true time and time again, feel free to poke holes in their ideas.
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    Quote Originally Posted by williampinn
    I see you are seeing the irony of it all. If there was anything to this feedback hypothesis, you should be able to perform the following experiment: Place some water in a sealed glass container. The greenhouse effect of the glass should warm up the water, causing water vapor. The water vapor should trap more heat and so on until the water reaches the boiling point.
    Oh, for god's sake. The vapor pressure of a liquid is approximately proportional to the temperature, while the radiative cooling power is proportional to the fourth power of the temperature. Which means that the rate at which the vapor pressure increases will be much lower than the rate at which the box's ability to radiatively cool itself increases. Eventually the box will reach an equilibrium where the power of its radiative cooling is equal to the power of the light hitting it. That equilibrium might or might not be above the boiling point of water, depending on how much light you're hitting it with and what sort of shape etc. the box has.

    You couldn't figure that out, and yet you think you're qualified to poke holes in climate models???

    There's also the minor detail that to do the experiment you would need to somehow suspend your box in a vacuum so that it can only lose heat through radiation, since otherwise it will simply cool down from conduction.
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    Kojax wrote:

    However, it is starting to look possible that CO2 is just a minor player.
    No, youíre missing the point. Water vapor alone wonít change the status quo. But since CO2 is increasing, it raises the temperature and allows the atmosphere to hold more water, which raises the temperature further. If CO2 stabilizes at a new higher level then the water vapor, and the temperature, will also stabilize, because itís an observed fact that the relative humidity tends to remain constant. But CO2 isnít stabilizing, itís continuing to increase, and so the absolute humidity will increase in tandem with the CO2, and the temperature increases more than it would by CO2 alone.

    CO2 is not a minor factor, it is the forcing agent.
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    Quote Originally Posted by williampinn
    What experts were correct? Do you have any sources? If you are right, then my history teachers lied to me. By the way, they are experts on history and you're not, but don't let that stop you from expressing your views, because even a stopped clock can be right twice a day.
    I would be astounded if a PhD historian who specialized in Columbus told you any of the bullshit that you appear to believe about him. If your "expert" teachers were dumbass highschool teachers with a B.S. in education or something, which seems most likely, then there's no telling what they might have told you.
    LOL! Einstein worked in the patent office in Bern Switzerland. He wasn't even in school. I see you like to make up stuff as you go along. You would make a great modern scientist. Try Googling next time.
    For fuck's sake, take your own advice. Einstein got twin university degrees in math and physics, THEN started working at a patent office because he couldn't get a university teaching job, which was what he really wanted. He got his PhD in theoretical physics the same year he published his first major papers, much of which was in his PhD thesis. This might be a bit of a surprise to you, but the patent office needs experts to evaluate patents. The fact that he worked at a patent office doesn't mean that he wasn't also an expert. There are many, many people with PhDs working in the US patent office, most of whom have published academic papers.
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    Quote Originally Posted by williampinn

    I have a lot of questions for those who think they know what happened on Venus.
    That's why its a hypothesis. Since then, the scientist have probably had a good chance to look at the isotope ratios of the remaining Hydrogen which would give a pretty good indication of how much water was originally on the planet. I haven't read a recent paper on the subject.

    I don't see how water vapor can cause a runaway effect.
    With increased surface warming from either direct energy or IR positive feedback of greenhouse effect (it's about 60F now), the surface temps eventually exceed the boiling point. Once that happens the lower atmosphere becomes completely saturated and provides even more feedback to warm the surface even more--eventually the entire atmosphere becomes saturated. And that when we start to loose a lot of photodissociated hydrogen. This is what they thing might have happened on Venus.


    It is lighter than air, so it rises to the atmosphere where it is cooler due to lower atmospheric pressure.
    Under current conditions the contribution of water vapor density doesn't matter much. Air rises primarily due to mixed parcels being warmer and less dense than its unsaturated surroundings--once saturated the latent heat of condensation adds heat and make it even warmer relative to its surroundings. The difference and contribution of water vapor density compared to the mixed parcel is so small it's generally ignored in weather models of convection. Under run-away conditions it would be more important.

    In addition the difference between the dry and the moint adiabatic lapse rate increases with temperature because hot air can hold much more water vapor than cold air--this becomes a strong positive feedback if an oceans were to approach the boiling point. (look up a rawinsonde's SkewT-LogP Diagram) This won't happen for a very long time on earth though--not until the radius of the sun become much larger--a billion or more years from now.
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    Quote Originally Posted by williampinn
    But I just got through showing you one climate model that did forget to consider it. You just got through NOT showing that there are any models that do. Does evidence or the the lack thereof matter to you?
    Okay, it seemed just astounding to me that someone would make a climate model that didn't take the boltzmann law into account, but you seemed so sure of yourself here that I went ahead and clicked your link. It appears that this model DOES account for the boltzmann law.

    Like I said, eventually an object that's being irradiated in space (like, say, a planet) will reach an equilibrium where the power of the radiative cooling is equal to the power of the incoming light. It appears that this guy set the standard equation for radiative cooling (which includes the boltzmann law, and includes a temp^4 term) equal to the power of incoming light. He then divided the incoming light power side of the equation by the radiative cooling side, except for the temp^4 part, which he left alone on radiative cooling side. It appears that he has bundled much of the radiative cooling equation (which would include a ton of stuff like the area of the earth, Stefan's constant, etc) into a much simplified form. It's not immediately clear exactly how he derived it, but it appears to be from some "model B" that his students are apparently supposed to already be familiar with. If he wasn't using the Boltzmann law, where the hell would you suppose the temp^4 part came from?
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    Quote Originally Posted by Scifor Refugee
    Quote Originally Posted by williampinn
    What experts were correct? Do you have any sources? If you are right, then my history teachers lied to me. By the way, they are experts on history and you're not, but don't let that stop you from expressing your views, because even a stopped clock can be right twice a day.
    I would be astounded if a PhD historian who specialized in Columbus told you any of the bullshit that you appear to believe about him. If your "expert" teachers were dumbass highschool teachers with a B.S. in education or something, which seems most likely, then there's no telling what they might have told you.
    Well no sources or links from you. I am not surprised. I guess now we know who really has a BS degree.

    Quote Originally Posted by Scifor Refugee
    LOL! Einstein worked in the patent office in Bern Switzerland. He wasn't even in school. I see you like to make up stuff as you go along. You would make a great modern scientist. Try Googling next time.
    For fuck's sake, take your own advice. Einstein got twin university degrees in math and physics, THEN started working at a patent office because he couldn't get a university teaching job, which was what he really wanted. He got his PhD in theoretical physics the same year he published his first major papers, much of which was in his PhD thesis. This might be a bit of a surprise to you, but the patent office needs experts to evaluate patents. The fact that he worked at a patent office doesn't mean that he wasn't also an expert. There are many, many people with PhDs working in the US patent office, most of whom have published academic papers.
    Whether we go with your version or the truth, the point is just the same: you don't have to be a PhD to be an expert. All the non-PhD people I mentioned were all experts in the sense that they knew how to get the job done. If that is now your defintion of an expert, then count me in as well. You have already seen that I can do some math. Now show me what you are good for. What can a carbon dioxide molecule do with IR at 10 microns?

    (Let's get back on topic please. I will refrain from the playground attacks if you will. )
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    Quote Originally Posted by williampinn
    What can a carbon dioxide molecule do with IR at 10 microns?
    Not sure why I missed that earlier. None of Co2's vibrational modes are sensitive to 10 microns. It's a different story at ~4 microns where is causes stretching vibrations and 14-15 microns where is causes bending vibrations.

    It won't emit anything at that frequency.
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    Quote Originally Posted by Scifor Refugee
    Quote Originally Posted by williampinn
    But I just got through showing you one climate model that did forget to consider it. You just got through NOT showing that there are any models that do. Does evidence or the the lack thereof matter to you?
    Okay, it seemed just astounding to me that someone would make a climate model that didn't take the boltzmann law into account, but you seemed so sure of yourself here that I went ahead and clicked your link. It appears that this model DOES account for the boltzmann law.

    Like I said, eventually an object that's being irradiated in space (like, say, a planet) will reach an equilibrium where the power of the radiative cooling is equal to the power of the incoming light. It appears that this guy set the standard equation for radiative cooling (which includes the boltzmann law, and includes a temp^4 term) equal to the power of incoming light. He then divided the incoming light power side of the equation by the radiative cooling side, except for the temp^4 part, which he left alone on radiative cooling side. It appears that he has bundled much of the radiative cooling equation (which would include a ton of stuff like the area of the earth, Stefan's constant, etc) into a much simplified form. It's not immediately clear exactly how he derived it, but it appears to be from some "model B" that his students are apparently supposed to already be familiar with. If he wasn't using the Boltzmann law, where the hell would you suppose the temp^4 part came from?

    Here's the equation you are refering to:

    So*(1-alpha)
    --------------------- = Tg^4 (1)
    4*sigma*(1-epsilon/2)

    How does a couple of similar terms make it the Stephen-Boltzman law?

    Here is the real equation:

    T^4 = P/(epsilon)(Area)(5.63 X 10^- 8)

    Here is another equation with T^4 in it:

    T^4 = (Q/cm)^4

    Or how about:

    T^4 = [(1- eff)Th]^4

    All three equations I listed are derived from various thermal equations but only one is the real McCoy that we are discussing. But note that all three could be erroneously labeled Stephen-Boltzman derivatives. They are not. Just because you see a familiar term in an equation, does not make it what ever law you want it to be. That is not good science or math. That is wishful thinking.
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    Quote Originally Posted by Lynx_Fox
    Quote Originally Posted by williampinn
    What can a carbon dioxide molecule do with IR at 10 microns?
    Not sure why I missed that earlier. None of Co2's vibrational modes are sensitive to 10 microns. It's a different story at ~4 microns where is causes stretching vibrations and 14-15 microns where is causes bending vibrations.

    It won't emit anything at that frequency.
    ARE YOU KIDDING ME?! Check Wien's equation. Take any temperature of the Earth you like:

    wavelength (W [in nanameters])= 2.9 X 10^6/287 K = 10,105 nm or about 10 microns.

    Earth's entire temperature range translates to IR at around 10 microns. How can the greenhouse effect happen if CO2 is not sensitive to 10 microns? For the greenhouse effect to work, the Earths temperature would have to be more than twice as hot as it is just to get the process started.

    4000 nm = 2.9 X 10^6/T
    4000T = 2.9 X 10^6
    T = 2.9 X 10^6/4000 = 725K! = 452 C! Or about 4.5 times as hot as boiling water.

    Good grief! How can anyone defend the greenhouse theory knowing any of this?
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    Quote Originally Posted by Lynx_Fox
    Quote Originally Posted by williampinn

    I have a lot of questions for those who think they know what happened on Venus.
    That's why its a hypothesis. Since then, the scientist have probably had a good chance to look at the isotope ratios of the remaining Hydrogen which would give a pretty good indication of how much water was originally on the planet. I haven't read a recent paper on the subject.

    I don't see how water vapor can cause a runaway effect.
    With increased surface warming from either direct energy or IR positive feedback of greenhouse effect (it's about 60F now), the surface temps eventually exceed the boiling point. Once that happens the lower atmosphere becomes completely saturated and provides even more feedback to warm the surface even more--eventually the entire atmosphere becomes saturated. And that when we start to loose a lot of photodissociated hydrogen. This is what they thing might have happened on Venus.


    It is lighter than air, so it rises to the atmosphere where it is cooler due to lower atmospheric pressure.
    Under current conditions the contribution of water vapor density doesn't matter much. Air rises primarily due to mixed parcels being warmer and less dense than its unsaturated surroundings--once saturated the latent heat of condensation adds heat and make it even warmer relative to its surroundings. The difference and contribution of water vapor density compared to the mixed parcel is so small it's generally ignored in weather models of convection. Under run-away conditions it would be more important.

    In addition the difference between the dry and the moint adiabatic lapse rate increases with temperature because hot air can hold much more water vapor than cold air--this becomes a strong positive feedback if an oceans were to approach the boiling point. (look up a rawinsonde's SkewT-LogP Diagram) This won't happen for a very long time on earth though--not until the radius of the sun become much larger--a billion or more years from now.
    So, in other words it takes a lot more energy than a few measly CO2 molecules can muster, especially when IR from Earth is around 10 microns. I always said, if you want to boil water, you can't just let the pot sit on the cold ground.
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    Quote Originally Posted by Bunbury
    Kojax wrote:

    However, it is starting to look possible that CO2 is just a minor player.
    No, youíre missing the point. Water vapor alone wonít change the status quo. But since CO2 is increasing, it raises the temperature and allows the atmosphere to hold more water, which raises the temperature further. If CO2 stabilizes at a new higher level then the water vapor, and the temperature, will also stabilize, because itís an observed fact that the relative humidity tends to remain constant. But CO2 isnít stabilizing, itís continuing to increase, and so the absolute humidity will increase in tandem with the CO2, and the temperature increases more than it would by CO2 alone.

    CO2 is not a minor factor, it is the forcing agent.
    How is CO2 a forcing agent when all temperatures at the Earth's surface emit around 10 microns of IR? Read Lynx's comments above and read my response using Wien's formula. Lynx seems to think CO2 is not sensitive to 10 microns but reacts well with 4 microns. Problem is, the Earth's temperature would have to be 4.5 times hotter than boiling water to emit 4 microns of IR. Does the math lie? Or do politicians who make movies?
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    Quote Originally Posted by williampinn

    How is CO2 a forcing agent when all temperatures at the Earth's surface emit around 10 microns of IR?
    There's part of your problem. It only peaks about near 10 microns; but the IR emission curve is very broad for earth--something like 2 - 50 microns.

    It's always pretty neat to see what's transmitted from the surface (top), and what's received in space (bottom)
    --
    As for Stephen-Boltzman law, I'm pretty sure it's correct, just in slightly changed form to account for some surface area term (hence the 4). I'll spend a couple minutes tomorrow and try to figure out the substitution they made.

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    Quote Originally Posted by williampinn
    Quote Originally Posted by Bunbury
    Kojax wrote:

    However, it is starting to look possible that CO2 is just a minor player.
    No, youíre missing the point. Water vapor alone wonít change the status quo. But since CO2 is increasing, it raises the temperature and allows the atmosphere to hold more water, which raises the temperature further. If CO2 stabilizes at a new higher level then the water vapor, and the temperature, will also stabilize, because itís an observed fact that the relative humidity tends to remain constant. But CO2 isnít stabilizing, itís continuing to increase, and so the absolute humidity will increase in tandem with the CO2, and the temperature increases more than it would by CO2 alone.

    CO2 is not a minor factor, it is the forcing agent.
    How is CO2 a forcing agent when all temperatures at the Earth's surface emit around 10 microns of IR? Read Lynx's comments above and read my response using Wien's formula. Lynx seems to think CO2 is not sensitive to 10 microns but reacts well with 4 microns. Problem is, the Earth's temperature would have to be 4.5 times hotter than boiling water to emit 4 microns of IR. Does the math lie? Or do politicians who make movies?
    This is the part I'm wondering too. The question for me is how large of an effect does the CO2 *need* to be?

    In the first place, I think we're making the classic physics mistake of confusing velocity with acceleration. Questions of absorbtion/emission rates are questions of acceleration. Climate change is a question of velocity. It doesn't matter whether the acceleration takes place in the past, present or future. If it isn't followed by a deceleration, then you'll stay permanently at the higher speed.

    Like the charge in the battery in a car. If an effect causes the Earth to absorb even a very tiny, tiny bit more heat than it's radiating away, that's going to store up over time. The only way any of it will ever be discharged is if we go past the point of equilibrium, instead of merely reaching it.

    So the question is: After reaching the equilibrium point, will the Earth begin to emit *more* heat than it takes in for a little while?
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    Quote Originally Posted by Lynx_Fox
    Quote Originally Posted by williampinn

    How is CO2 a forcing agent when all temperatures at the Earth's surface emit around 10 microns of IR?
    There's part of your problem. It only peaks about near 10 microns; but the IR emission curve is very broad for earth--something like 2 - 50 microns.

    It's always pretty neat to see what's transmitted from the surface (top), and what's received in space (bottom)
    --
    As for Stephen-Boltzman law, I'm pretty sure it's correct, just in slightly changed form to account for some surface area term (hence the 4). I'll spend a couple minutes tomorrow and try to figure out the substitution they made.

    Obviously, the IR that Earth emits that CO2 reacts to is very small compared to the range of the coldest and warmest temperatures recorded. Even if you take the most extreme temperatures recorded (e.g. Antarctica and the Equator) the emissions fall very close to 10 microns. Wien's equation clearly shows that.

    That second chart is bogus. If you do the math, 280K comes out to 10,357 nm, not the longer wavelengths it's showing. Wavelengths of 20,000 nm or more correspond to temperatures as cold or colder than Antarctica. Yet such cold temperatures appear at the top of the bell curve? Uh huh.

    T = 2.9 X 10^6/20000 nm = 145K! -128 C.

    Clearly the mean temperature (10 microns wavelength) of the Earth (287 K, 14 C) should be at the top of the curve.


    If Stephen-Bolzman's equation was used in that computer model, it can't have a runaway effect then.
    http://www.gather.com/viewArticle.js...81474977665371
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    Quote Originally Posted by williampinn
    Wien's equation clearly shows that.
    Keep in mind, if you haven't yet, that Wien's law is for the wavelength where the maximum power is output. Meaning that there's a full spectrum of colors emitted from bodies of any temperature.

    See wiki.
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    Quote Originally Posted by kojax
    This is the part I'm wondering too. The question for me is how large of an effect does the CO2 *need* to be?

    In the first place, I think we're making the classic physics mistake of confusing velocity with acceleration. Questions of absorbtion/emission rates are questions of acceleration. Climate change is a question of velocity. It doesn't matter whether the acceleration takes place in the past, present or future. If it isn't followed by a deceleration, then you'll stay permanently at the higher speed.

    Like the charge in the battery in a car. If an effect causes the Earth to absorb even a very tiny, tiny bit more heat than it's radiating away, that's going to store up over time. The only way any of it will ever be discharged is if we go past the point of equilibrium, instead of merely reaching it.

    So the question is: After reaching the equilibrium point, will the Earth begin to emit *more* heat than it takes in for a little while?
    Read this:
    http://www.gather.com/viewArticle.js...81474977665371

    I show in the simplest terms possible how added energy to any system has less and less impact. To double the Earth's temperature would require more than 10 times the output of the sun's current energy. To raise the Earth's temperature a small fraction, would require a doubling of the sun's energy. I seriously doubt CO2 can match the sun's energy let alone multiple sun energy.
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    Quote Originally Posted by Numsgil
    Quote Originally Posted by williampinn
    Wien's equation clearly shows that.
    Keep in mind, if you haven't yet, that Wien's law is for the wavelength where the maximum power is output. Meaning that there's a full spectrum of colors emitted from bodies of any temperature.

    See wiki.
    But the colors you are thinking of are more than two standard deviations from the center of the bell curve and thus would be insignificant. CO2 molecules will come into contact with wavelengths within two standard deviations of the center of the curve 90-95% more often. If I am wrong then we should all fry or freeze in our beds at night due to the high intensity or low intensity radiation coming from the ground.
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    You're dealing with some pretty big exponents. An "insignificant" value of 10^-6 becomes very significant if you multiply it by 10^14.
    "A witty saying proves nothing." - Voltaire
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    Quote Originally Posted by Numsgil
    You're dealing with some pretty big exponents. An "insignificant" value of 10^-6 becomes very significant if you multiply it by 10^14.
    I am not sure from which dark place you got those numbers, but if the floor does not fry or freeze your feet, then the impact of those seemingly big numbers is nil.
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    Quote Originally Posted by williampinn
    Quote Originally Posted by Numsgil
    You're dealing with some pretty big exponents. An "insignificant" value of 10^-6 becomes very significant if you multiply it by 10^14.
    I am not sure from which dark place you got those numbers, but if the floor does not fry or freeze your feet, then the impact of those seemingly big numbers is nil.
    <= 10^-6 is my definition of "insignficant". 5.10072 X 10^14 is from the third page of this thread.
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    Quote Originally Posted by williampinn
    Quote Originally Posted by kojax
    This is the part I'm wondering too. The question for me is how large of an effect does the CO2 *need* to be?

    In the first place, I think we're making the classic physics mistake of confusing velocity with acceleration. Questions of absorbtion/emission rates are questions of acceleration. Climate change is a question of velocity. It doesn't matter whether the acceleration takes place in the past, present or future. If it isn't followed by a deceleration, then you'll stay permanently at the higher speed.

    Like the charge in the battery in a car. If an effect causes the Earth to absorb even a very tiny, tiny bit more heat than it's radiating away, that's going to store up over time. The only way any of it will ever be discharged is if we go past the point of equilibrium, instead of merely reaching it.

    So the question is: After reaching the equilibrium point, will the Earth begin to emit *more* heat than it takes in for a little while?
    Read this:
    http://www.gather.com/viewArticle.js...81474977665371

    I show in the simplest terms possible how added energy to any system has less and less impact. To double the Earth's temperature would require more than 10 times the output of the sun's current energy. To raise the Earth's temperature a small fraction, would require a doubling of the sun's energy. I seriously doubt CO2 can match the sun's energy let alone multiple sun energy.
    I think perhaps you are misunderstanding me.

    Heat is not the state of continually getting more hot. It is the state of having once gotten hot, and not thereafter having been cooled.

    Quote Originally Posted by The Article

    Things have a nasty habit of reaching equilibrium. The following heat-engine equation demonstrates this:

    Ef = 1-(Ta/Tg)

    Ef is the efficiency of the system; Ts is the surface temperature and Ta is the atmospheric temperature. For warming to occur, Tg must be warmer than Ta. If the surface is the same temperature or cooler than the surrounding air, guess what? Global warming can't happen. Check it out:

    Let's say Tg = 4C and Ta = 3C. 1 - 3/4 = .25. The efficiency of the heat engine in this case is .25. However, Tg will pass its heat on to Ta until both are the same temperature, then the warming stops because:

    1-(3.5/3.5) = 0. An efficiency of zero stops the entire warming process. That is why your car can only get so hot and why a runaway greenhouse effect is impossible.

    Given a fixed amount of energy from the sun, no system on Earth can warm up beyond a certain point. This is true under the Stephan-Boltzman Law, which is expressed as follows:

    P = eAoT^4
    I know the earth isn't going to boil itself to death like Venus. The temperature will only continue to rise until a new equilibrium is reached but : It will stay at the new, higher temperature forever unless something brings it even further than equilibrium, to the point where some actual cooling occurs.

    A permanent increase of say.... 5 degrees Farenheit worldwide could do some really nasty stuff.
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    Quote Originally Posted by williampinn
    That second chart is bogus. If you do the math, 280K comes out to 10,357 nm, not the longer wavelengths it's showing. Wavelengths of 20,000 nm or more correspond to temperatures as cold or colder than Antarctica. Yet such cold temperatures appear at the top of the bell curve? Uh huh.
    It's not Bogus Gary, it's actually what's observed by satellite. You might not like it, but it's actually observations. The one above shows the broad width of the emission spectrum, ALL black bodies emit on very wide bands. I have no idea why you're focused on one narrow frequency.
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    Quote Originally Posted by williampinn
    To double the Earth's temperature would require more than 10 times the output of the sun's current energy. To raise the Earth's temperature a small fraction, would require a doubling of the sun's energy. I seriously doubt CO2 can match the sun's energy let alone multiple sun energy.


    The entire range of surface temperature change for adding Co2 as a green house gases is less than a 2% of the current temperature.

    Why are we discussing raising the temperature by more than 400F? Even the ~25% temperature increase to create a run away green house is out of reach until the sun gets a lot brighter.
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    Quote Originally Posted by williampinn
    All three equations I listed are derived from various thermal equations but only one is the real McCoy that we are discussing. But note that all three could be erroneously labeled Stephen-Boltzman derivatives. They are not. Just because you see a familiar term in an equation, does not make it what ever law you want it to be. That is not good science or math. That is wishful thinking.
    Okay, I went through the trouble to sit down with a pencil and tried to derive the equilibrium temp at the earth's surface based on the boltzmann equation, and I got the same thing he did.

    The power of sunlight hitting the earth will be S*pi*r^2*(1-alpha), where S is the solar constant, r is the earth's radius, and alpha is the albedo.

    Set that equal to the power of the earth's cooling. If you treat the earth's surface as a black body, the power of the earth's surface's radiative cooling would be 4*pi*r^2*sigma*T^4, where sigma is stefan's constant and T is temp.

    BUT we have not yet taken the greenhouse effect into account. To do that, we need to consider the emissivity of the atmosphere. The higher the emissivity, the more IR will be reflected back to the ground instead of being radiated away into space. This is the purpose of the (1-epsilon/2) term in the denominator. You might have been confused about the way in this model epsilon is the emissivity of the atmosphere, not the earth itself. There is no emissivity term included for the radiating surface (the ground below the atmosphere) because it's treated as a black body. I don't know why exactly he used 1-epislon/2, I guess it has something to do with the odds of an IR photon being reflected back before escaping based on the emissivity of the atmosphere. But that part of the equation didn't actually come from the classical Boltzmann law, it's an addition to the Boltzmann law to account for the fact that a percentage of the radiant energy that would normally escape from a black body is being reflected back to the surface.

    To sum up:
    1. This guy clearly was using the Boltzmann law.
    2. It should have taken you about 2 minutes of algebra and basic geometry to figure that out.
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    Quote Originally Posted by kojax
    A permanent increase of say.... 5 degrees Farenheit worldwide could do some really nasty stuff.
    What would cause a permanent increase? As far as I know the climate always changes. A 10 degree increase would be even nastier. A 1000 degree increase would be nastier still. The problem here is there is a lack of empirical evidence to justify even the 5 degree increase allegedly caused by anthropogenic global warming.

    Anyone can dream up scary scenarios and pick a big number. That is not science however. What I have done is test the claims made by the global warming crowd against an established law of physics to see if those claims really work. They do not. And no one has shown otherwise. The best the proponents can do is fall back on political mantras.
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    Quote Originally Posted by Scifor Refugee
    Quote Originally Posted by williampinn
    All three equations I listed are derived from various thermal equations but only one is the real McCoy that we are discussing. But note that all three could be erroneously labeled Stephen-Boltzman derivatives. They are not. Just because you see a familiar term in an equation, does not make it what ever law you want it to be. That is not good science or math. That is wishful thinking.
    Okay, I went through the trouble to sit down with a pencil and tried to derive the equilibrium temp at the earth's surface based on the boltzmann equation, and I got the same thing he did.

    The power of sunlight hitting the earth will be S*pi*r^2*(1-alpha), where S is the solar constant, r is the earth's radius, and alpha is the albedo.

    Set that equal to the power of the earth's cooling. If you treat the earth's surface as a black body, the power of the earth's surface's radiative cooling would be 4*pi*r^2*sigma*T^4, where sigma is stefan's constant and T is temp.

    BUT we have not yet taken the greenhouse effect into account. To do that, we need to consider the emissivity of the atmosphere. The higher the emissivity, the more IR will be reflected back to the ground instead of being radiated away into space. This is the purpose of the (1-epsilon/2) term in the denominator. You might have been confused about the way in this model epsilon is the emissivity of the atmosphere, not the earth itself. There is no emissivity term included for the radiating surface (the ground below the atmosphere) because it's treated as a black body. I don't know why exactly he used 1-epislon/2, I guess it has something to do with the odds of an IR photon being reflected back before escaping based on the emissivity of the atmosphere. But that part of the equation didn't actually come from the classical Boltzmann law, it's an addition to the Boltzmann law to account for the fact that a percentage of the radiant energy that would normally escape from a black body is being reflected back to the surface.

    To sum up:
    1. This guy clearly was using the Boltzmann law.
    2. It should have taken you about 2 minutes of algebra and basic geometry to figure that out.
    Well he wasn't using the law in its original form. Additionally his substitutions and changes need to be empirically justified. At least we know the equation in its original form has been tested against the real world. You have shown that you can crunch some numbers. Now all you have to do is show in mathematical and scientific terms that a runaway greenhouse effect can happen notwithstanding the limitation the Stephen-Boltsman law creates.

    I think that will be a difficult task though, because apparently CO2 is insensitive to the typical IR wavelength coming from Earth's surface which is around 10 microns. Further, there is precious little CO2 to work with, and high in the atmosphere there is even less due to reduced air pressure and the high density of CO2.
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    Quote Originally Posted by Lynx_Fox
    Quote Originally Posted by williampinn
    That second chart is bogus. If you do the math, 280K comes out to 10,357 nm, not the longer wavelengths it's showing. Wavelengths of 20,000 nm or more correspond to temperatures as cold or colder than Antarctica. Yet such cold temperatures appear at the top of the bell curve? Uh huh.
    It's not Bogus Gary, it's actually what's observed by satellite. You might not like it, but it's actually observations. The one above shows the broad width of the emission spectrum, ALL black bodies emit on very wide bands. I have no idea why you're focused on one narrow frequency.
    Why am I focused on the truth? It is simple really. The truth matters to me. Satellite data has falsified Wien's equation? Since when?
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    Quote Originally Posted by Numsgil
    Quote Originally Posted by williampinn
    Quote Originally Posted by Numsgil
    You're dealing with some pretty big exponents. An "insignificant" value of 10^-6 becomes very significant if you multiply it by 10^14.
    I am not sure from which dark place you got those numbers, but if the floor does not fry or freeze your feet, then the impact of those seemingly big numbers is nil.
    <= 10^-6 is my definition of "insignficant". 5.10072 X 10^14 is from the third page of this thread.
    Now all you need to do is show us something using your numbers. Anything at all.
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    Quote Originally Posted by williampinn
    Well he wasn't using the law in its original form.
    I'm not sure what you mean here. It appears that he was using the standard boltzmann law as applied to a sphere that's being irradiated from a point source. He just didn't show all his algebra, but it checks out if you would bother to try to derive it yourself.
    Additionally his substitutions and changes need to be empirically justified.
    What substitutions?

    It's obvious that this page is meant for students in his class, who are apparently already supposed to be familiar with how the equation was derived. It's not meant to be a thorough argument for convincing random people who stumble across it.
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    Quote Originally Posted by williampinn
    Quote Originally Posted by Lynx_Fox
    Quote Originally Posted by williampinn
    That second chart is bogus. If you do the math, 280K comes out to 10,357 nm, not the longer wavelengths it's showing. Wavelengths of 20,000 nm or more correspond to temperatures as cold or colder than Antarctica. Yet such cold temperatures appear at the top of the bell curve? Uh huh.
    It's not Bogus Gary, it's actually what's observed by satellite. You might not like it, but it's actually observations. The one above shows the broad width of the emission spectrum, ALL black bodies emit on very wide bands. I have no idea why you're focused on one narrow frequency.
    Why am I focused on the truth? It is simple really. The truth matters to me. Satellite data has falsified Wien's equation? Since when?
    Trying to explain how this works to you because you seem ignorant about how broad blackbody IR emissions are at earth surface temperature. The surface emissions at 14-15nm, which is where Co2 is sensitive, are about 2/3s of what they are at the 10nm peak. You can confirm in any depiction of Planck's Radiation function which shows the IR bands. The emission from 9nm to 11nm is only a fraction of the total.

    The satellite data doesn't conflict with Wien's law at all, because it's measuring the IR after the atmosphere absorbs what's emitted from the surface (mostly). I showed the slide because the Co2 absorption near 14nm is easy to see.
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    Quote Originally Posted by williampinn
    Quote Originally Posted by kojax
    A permanent increase of say.... 5 degrees Farenheit worldwide could do some really nasty stuff.
    What would cause a permanent increase? As far as I know the climate always changes. A 10 degree increase would be even nastier. A 1000 degree increase would be nastier still. The problem here is there is a lack of empirical evidence to justify even the 5 degree increase allegedly caused by anthropogenic global warming.

    Anyone can dream up scary scenarios and pick a big number. That is not science however. What I have done is test the claims made by the global warming crowd against an established law of physics to see if those claims really work. They do not. And no one has shown otherwise. The best the proponents can do is fall back on political mantras.
    In case you didn't read the whole post, I was saying that, if there's an increase, it must be a permanent one. If the temperature of the Earth rises until a new equilibrium stops it from rising further, the fact we reached a new equilibrium doesn't mean the temperature is going to go back down.

    You've demonstrated that something will stop the temperature rising until the seas begin to boil. And you are right about that. What you haven't demonstrated is that after something stops the temperature increases, it will then cause the temperature to go back down again.

    Here's the thing: it's like pouring drops of water into a bucket. Even if the CO2 and or direct heating were the tiniest possible drop of water ("drop in the bucket") imaginable, gradually that bucket is still going to fill. As long as the CO2 causes some absorption, and nothing else cancels that effect.

    The temperature of the Earth is based on how much heat has accumulated over time, not how much more we're adding every day. The only way the temperature ever drops is if we emit more heat than we take in. So, it's not a question of whether we reach equilibrium. It's a question of whether we surpass equilibrium.
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