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Visual depictions of CO2 levels and CO2 emissions

Posted on 18 February 2010 by John Cook

Measurements of atmospheric carbon dioxide come from more than a single station on a Hawaiian volcano. There are ground based stations scattered across the globe taking direct measurements. Three independent satellites take global CO2 measurements: the Atmospheric Infrared Sounder (AIRS) on the NASA Aqua spacecraft, Envirosat by the European Space Agency and IBUKI by the Japan Aerospace Exploration Agency. For periods before direct measurements, CO2 can be determined from Antarctic and Greenland ice cores. Here are some visual summaries of CO2 data:

This first video shows surface measurements of CO2 varying over different latitudes from 1979 to 2006. The graph is created by Andy Jacobson from the NOAA. It's packed with information - there's a global map displaying where the measurements are coming from, a comparison of Mauna Loa CO2 to South Pole CO2 and the graph expands at the end to include ice core measurements back to the 19th Century.

Satellites present a fuller picture of global CO2 concentration. The next video shows global distribution of mid-tropospheric carbon dioxide. This data comes from the Atmospheric Infrared Sounder (AIRS) on the NASA Aqua spacecraft. You can download the original movie from the NASA website. Superiposed over the global map is a graph of carbon dioxide observed at the Mauna Loa, Hawaii observatory.

Where does the CO2 come from? The following video begins with a map of CO2 emissions across the U.S.A. using the Vulcan model by Purdue University. Vulcan uses local data on air pollution to calculate a high resolution map of CO2 emissions on an hourly basis. Of particular interest are several animations of how the CO2 mixes through the atmosphere, transporting CO2 from the U.S. over the North Atlantic.

Of course, the U.S. is not the whole world (some need occasional reminding of this fact). The animation of CO2 being transported into the North Atlantic makes you wonder how CO2 is transported throughout the globe. This is displayed in a CarbonTracker visualisation of global transportation of CO2 through 2008 (more on CarbonTracker).

The following movie shows mid-tropospheric carbon dioxide from July 2003, measured by the Atmospheric Infrared Sounder (AIRS). Low concentrations (360 ppm) are shown in blue and high concentrations (385 ppm) are shown in red. In the southern hemisphere, the jet stream flow is more directly West to East. During the period from July to October, the CO2 concentration is enhanced in a belt delineated by the jet stream and lofting of CO2 into the free troposphere by the high Andes is visible in this period. The zonal flow of CO2 around the globe at the latitude of South Africa, southern Australia and southern South America is readily apparent. You can download the original movie from the NASA website.

Acknowledgements: many thanks to Peter Hogarth for tracking down many of these animations.

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Comments 1 to 50 out of 52:

  1. John,

    I'm not seeing the videos in Firefox. The blocks of space where they should be are there, the object code is there behind the scenes, and I can copy the Youtube links into a new window and watch the videos directly, but nothing in this page.
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    Response: Thanks for the heads-up, it's a glitch in my admin system that changes the YouTube code enough to break it in Firefox but not in Internet Explorer, hence I didn't notice the error.

    Yes, it's true, I use Internet Explorer :-(
  2. The videos work now in Firefox. Fabulous.
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  3. Wow! Nice. I wonder what are the causes of plumes over equatorial Africa and South America in the NOAA vid. I'm leaning toward fires.
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  4. You're almost certainly correct, Phillipe, as we know how much people are destroying the rain-forests of Africa & South America. This isn't just putting CO2 into the atmosphere, it is also leading to reductions in regional rainfall, the loss of valuable soil nutrients, increased risk of exposure to disease vectors (like Ebola) & the endangerment of thousands of species of animals & plants. I don't like to sound pessimistic, but I suspect that Homo Sapien Sapien will be one of the shortest lived species on the planet to date!
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  5. Philippe, if I remember correctly the plumes are indeed attributed to the usual suspects, "natural" and man made fires, as well as plant respiration and fossil fuel burning. Elsewhere on the AIRS sites plumes over South Africa are attributed to their intensive coal liquidation industry and in Eastern Australia are attributed to coal fired power generation. The surprising thing is that the AIRS data is from around 8km up, and yet concentrations are still localised. There is information (and even some animations) on vertical transport on the ENVISAT site, which helps clarify what is happening.
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  6. Here are animations of carbon dioxide and methane from Sciamachy (2003-2005).
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  7. The IPCC report mentions the SIO and the NOAA/GMD networks as the most comprehensive ones. Mauna Loa is not even included in those ones, and it does not have anything to do with the volcanic emissions, but with its altitude:

    “In 2005, the global mean average CO2 mixing ratio for the SIO network of 9 sites was 378.75 ± 0.13 ppm and for the NOAA/GMD network of 40 sites was 378.76 ± 0.05 ppm, yielding a global average of almost 379 ppm. For both networks, only sites in the remote marine boundary layer are used and high-altitude locations are not included. For example, the Mauna Loa site is excluded due to an ‘altitude effect’ of about 0.5 ppm.” (from the page linked)
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  8. For some reason, none of the videos played in my Firefox, with the exception of the third, 'revolutionary' one.
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  9. I have been told that greenhouse gases do not stop IR emissions, but rather only slow them down. So if the Earth is warming, shouldnt satellites in any case be detecting more IR rather than less? Since more surface heat would imply more IR energy. From what I have been told however, satellites are detecting lower IR emmisions, and thus proving CO2 is the main cause of AGW.
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  10. RSVP,
    GHG's absorb specific bands of IR emissions. In the case of CO2 it is around 15 um (650-750 cm^-1). GHG's also EMIT IR radiation at the brightness temperature of the gas over the same band. Greenhouse warming theory is that IR that OTHERWISE would have gone straight out will be absorbed and re-emitted, with some large fraction going back down rather than up and out.

    So, if the Earth is warming due to less IR emissions to space (which is the theory as far as I understand it), then you would expect less IR measured by satellites.

    In fact, satellites have measured MORE IR emissions to space, particularly in the 800-1000 cm^-1 band (not CO2).

    You will find a graph (Fig 2C, Harries 2001) on this site that would give you the impression less IR is escaping to space. That is NOT THE CASE. Figure 2B shows the spectrum prior to removing the non-GHG effects. There are also many other measurements of TOTAL outgoing IR done by satellites showing INCREASING IR loss to space.

    Note that CO2 Greenhouse effect warming the Earth, causing more IR emissions from the surface, resulting in more loss to space does not follow the fundamental law of conservation of energy.

    From what I can see, CO2 CAUSING the warming is not consistent with these observations. I would happily concede that CO2 could exacerbate SOME OTHER CAUSE.
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    Response: Harries 2001 does not find more IR escaping out to space. This is because it doesn't cover the whole spectrum - the missing part is at lower wavelengths, where there is much absorption due to CO2 and water vapour feedback. What it does find is the change in outgoing spectrum matches very closely with how we expect greenhouse gases to absorb outgoing energy which is confirmation of theory and an enhanced greenhouse effect.
  11. RSVP,

    It must be understood that Convection and Evaporation move far more energy from the surface of the planet to the Tropopause than does Radiation.

    If you actually attempt to describe the GHE as a picture, it would have a net as a roof ~10,000 meters high and no walls. There is only 1 CO2 molecule for every 2600 O2 and N2 molecules, so the atmosphere is also very transparent to IR.

    The GHE is a misnomer and has been grossly overestimated as to its ability to 'trap' heat, especially when taking into account the massive cooling effects of Convection and Evaporation.
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  12. RSVP & guinganbresil, 'infrared radiation' covers a huge range of EM wavelengths. Your statements above about whether IR radiation is increasing or decreasing are faulty due to overgeneralizing;

    Wavelengths of infrared absorbed by GHGs have shown decreased amounts escaping the atmosphere and increased amounts radiating down to the surface. Other wavelengths of infrared have increased both in amounts escaping and warming the surface.
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  13. My initial suspicion was that the central African plume derived from gas flaring from Nigeria's oil industry - there are places in Nigeria that haven't seen darkness in decades due to the unceasing flares - and indeed this graph shows they are #2 in the Sub Sahara - but primarily due to land use change and forestry, not fossil fuel production. Of course the two can reinforce one another. Graph from Anthropogenic CO2 emissions in Africa, published March 2009.

    Thanks for the visuals!
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  14. As the saying goes, a picture is worth a thousand words. These videos (I particularly like the first one with the timeline starting in 1979) should be required viewing for anyone who doubts humans are adding CO2 to the atmosphere.
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  15. Sorry John, I've just learned Andy Jacobson from the same NOAA lab did this version of the Surface Station visualisation. Their team also has CarbonTracker on their ftp, I think this is Andys also but will check.
    Re 3: (nice) and SCIAMACHY on ENVISAT, worth mentioning that Bremen University have independently matched the CO2 data from Mauna Loa etc and also provided an independent reality check of CarbonTracker (which is observations plus model) as well as producing many impressive real data based images of CO2 and CH4 sources on brand new version of:

    iup.uni-bremen.de/.../wfmd_image_gallery_co2.html

    (Michael Buchwitz is the creator). This has grown into a wonderful collection of images since last I looked.
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    Response: Thanks, have updated the text. Also updated the post with links to the original source of the two NASA animations for those who'd like to download the animations as movie files.
  16. @ RSVP at 00:18 AM on 19 February, 2010

    In the long run, energy in equals energy out. After a CO2 molecule, or any gas molecule for that matter, absorbs a quantum of energy, it emits it at the same wavelength as it was absorbed, and it a random direction; this basically means 50% up and 50% down. So, the CO2 in the atmosphere acts like a very fuzzy reflector. The net effect of increasing the amount of CO2 is that the black body radiation emitted at the surface has to shift to a slightly higher mean wavelength to get the same amount of energy out as is coming in. Higher medium wavelength is the same as higher temperature, as far as energy emitted by a solid is concerned.
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  17. Theendisfar,

    I suggest you research and calculate how much our "very transparent to IR" atmosphere can attenuate an IR beam in just a few meters - particularly at the 15um range.

    I can help providing the coefficients and formulas if you want, but I think it would be much more convincing if you figured it out by yourself.
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  18. Theendisfar,
    "I suggest you research and calculate how much our "very transparent to IR" atmosphere can attenuate an IR beam in just a few meters - particularly at the 15um range."

    Let's suppose (in the worst case) every ounce of IR energy were absorbed within a few meters. This would simply raise the radiative heat source a few meters off the ground... or is the energy just going to stay there forever hovering over the ground?
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  19. I would be interested in an animation of how CO2 moves to the surface in order to exchange with the vegetation and waters as this is where the greatest interaction occurs and ultimately all CO2 will be cycled through there, at least statistically.
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  20. @ RSVP at 03:45 AM on 20 February, 2010

    Not 100% sure if you are making this mistake, but be sure you are not thinking of the atmosphere as being of a uniform density. It gets less dense with altitude quickly. Near the surface, the GHGs may be relatively opaque and energy would rattle around for some time before gradually making progress outward; as energy moves outward, the lower density of the GHGs makes it more likely for it to travel a further distance before being captured by a GHG molecule. At higher altitudes, any bits emitted outward are more likely to continue outward. Increasing CO2 concentration effectively raises the altitude at which it becomes more likely for the energy to escape than not.

    That aside, convection plays a large role in the process of transporting energy up from the surface as well; so, no matter how thick the atmosphere is with GHGs, the energy will not 'just stay there'.
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  21. theendisfar at 01:38 AM on 19 February, 2010
    RSVP,

    "The GHE is a misnomer and has been grossly overestimated as to its ability to 'trap' heat, especially when taking into account the massive cooling effects of Convection and Evaporation. "

    Not sure what you mean by the cooling effect of evaporation. The gas media becomes a little warmer and the liquid media becomes a little cooler. Conservation of energy dictates that the net effect is zero. Of course, if the gas media becomes warmer, then convection becomes stronger, but that doesn't mean that evaporation+convection somehow anticipate a change in energy flux and prevent it from having an effect.

    As far as the size of the effect goes, the best estimates so far of a doubling of CO2 concentration are a base effect of, in round numbers, 1 K, and a fast-feedback of around 3 K. That's roughly a change of 0.5% and 1% in temperature, respectively. Granted, that's not much of a change on an absolute, physics scale, but it's quite a change within the band of what we think of as a temperate climate.
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  22. ...but that doesn't mean that evaporation+convection somehow anticipate a change in energy flux and prevent it from having an effect.

    Otherwise, there would not be the wide range of climate conditions seen in the geologic record. Those same changes in climate that are often cited as evidence that humans are not altering the climate now somewhat preclude the idea that convection has a strong buffering effect.
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  23. Chris G
    "Near the surface, the GHGs may be relatively opaque and energy would rattle around for some time before gradually making progress outward; "

    When I made that remark #18, I was attempting to let Alexandre consider what he told theendisfar, taking his remark it to its logical conclusion, and so point out an untruth. In doing so, you use the term "rattle around". Why not diffuse or disperse?
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  24. RSVP,

    I assume you're using the saturation argument. Following the question you stated: does it simply raise the radiative source or does the energy hover somewhere forever?

    Well, if we had to pick one, the answer would be closer to the latter. The correction I'd point is not that it "simply" raises the source. This has consequences.

    You must keep in mind that it's not exactly "absorption", but attenuation by scattering. So the energy caught by CO2 at some point of the atmosphere is reemited to random directions, including upwards. The upper layers get somewhat less energy than the lower ones, and so the warming goes on even if these lower layers are already at their saturation.

    This webpage does a nice illustrative mathematical model of this.

    There's also the RealClimate post on this.
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  25. RVSP,

    Please correct: closer to the *former* (not the latter)

    And also: The saturation argument and the "atmosphere has so little CO2 that it doesn't have any effect" argument are pretty much mutually exclusive.
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  26. @ RSVP at 06:27 AM on 20 February, 2010

    I understood that you were referring to the interaction between theendisfar and Alexandre. You were setting up a straw man that was a) beyond any reasonable inference from what Alexandre said, and b) pretending that the people who study the atmosphere and climate are unaware that there is such a thing as convection.

    I used the term "rattle around" because there are two models for EM radiation, as waves and as particles, I was thinking in terms of individual quanta, and I decided that it the context of a blog, I was not subject to the same precision of language requirements as would be required in a journal article, as long as the meaning was clear.
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  27. RSVP writes: When I made that remark #18, I was attempting to let Alexandre consider what he told theendisfar, taking his remark it to its logical conclusion, and so point out an untruth.

    Not trying to be rude or anything, but Alexandre has a much better understanding of this than you do. Thus, your tone here smacks a bit of the whole D-K effect.
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  28. Ned, Chris G, Alexandre

    What is all this about straw man, DK effect, saturation argument, etc. Why not give straightforward answers? Like exactly how much IR would attenuate over a few meters? (if you happen to know).

    Any energy imparted on the atmosphere should raise the temperature of the atmosphere. Fine. But isnt this just another arbitrary launch pad for cooling the Earth?

    I would prefer not to use analogies, but this one seems very illustrative.... I have an electric radiator for heating my room. I throw a blanket over it. (no danger of fire assumed) Perhaps during one hour I notice the heat isnt getting to me as before, but after a while, it makes no difference as the blanket comes up to temperature. The blanket does not impede the net heat flow delivered to the room. As they say, "Watts is Watts."

    The analogy refers to the original question as to whether more or less IR should be detected by satellites. Based on the blanket analogy, it looks in any case that IR levels might drop, but overall, they should stay the same.
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  29. Chris G
    I dont have a problem with the word "rattle" for energy that just sits there all day. But in this case it doesnt. It has more "initiative" than that, and will tend with a higher probability to migrate to where there is less. I guess that was my point.
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  30. RSVP,
    indeed the atmospheric greenhouse gas effect is often (popularly) described as a blanket. Below the blanket it will definitely be warmer.
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  31. RSVP,

    You're partly right. With increased CO2, the IR emmissions would be lower in its absorption band, but overall the IR would be the same given enough time.

    The problem is, temperature would have to raise to reach that equilibrium again.

    Here's a model kindly made available online by David Archer at the University of Chicago. Try this:

    - click "submit the calculation" to see the graph of the outgoing longwave radiation. That's the IR emitted by the planet. The big "bites" you see on the bell shaped curve are the greenhouse gases' absorption bands.

    - write down how much energy the Earth is emitting (Iout).

    - increase the CO2 on the left to, say, 750ppm, and submit the calculation again. You'll see the Iout has decreased.

    - Now increase the Ground temperature on the left and try to balance the Iout to its original amount.

    There. CO2 stopped some of the radiation to escape, total energy emitted got lower, the retained energy caused the temperature to rise, energy balance was restored.

    Did it get clearer? Please feel free to ask if it's not. I'm no expert, but it would be my pleasure to do my best to answer.
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  32. Here's a leading question which may well display my ignorance, but please answer (skeptically or otherwise!) if this is your area of expertise. Assuming a significant fraction of the global CO2 sink is (for example) the high Northern latitude forests and vegetation in the growing season, and a significant Global Methane source is high Northern latitude wetlands in Summer/Autumn, then how much of the Anthropogenic Carbon drawn down as CO2 then makes its way back into the atmosphere as CH4 through decay of some of that "extra" growth, - with potentially 21 times the Greenhouse effect??? I'm not sure if this carbon rectification/GHG amplification idea is original or even significant, but it would be interesting to run the math...
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  33. Riccardo at 21:23 PM on 20 February, 2010
    "RSVP,
    indeed the atmospheric greenhouse gas effect is often (popularly) described as a blanket. Below the blanket it will definitely be warmer"
    Consider what happens to the heat. Instead of residing in the surface (asphalt, trees, houses, people, ocean water, etc.), some portion that would otherwise escape to infinity, is instantaneously coupled into the atmosphere and thus raising its temperature. Whatever heat is picked up by the atmosphere for GHG, is actually lost on the surface. This implies, ironically, that the Earth's surface is actually a little cooler because of the GHG. Only the air has warmed up some. The net energy stays the same however.

    And all of the above is only true if the radiative cooling efficiency of a transparent gas such as our atmosphere is equal to those of the surface. If the efficiency is lower, than yes, the steady state energy level will be raised for more GHG.

    So with this, while I am conceding a theoretical raising of atmospheric temperature. However, accumulation of heat is a separate and possibly more important question, which depends on the comparative cooling efficiency between the surface and the atmosphere.
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  34. Alexandre
    "There. CO2 stopped some of the radiation to escape, total energy emitted got lower, the retained energy caused the temperature to rise,..."

    Does the atmosphere hold on to this energy forever? Does it not also radiate? Why doesnt the tool also account for this leakage?
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  35. Has anyone ever seen one of those 'energy in vs energy out' greenhouse effect charts for the estimated greenhouse at the end of the last ice age (~180 ppm CO2) and/or double the pre industrial revolution value (~560 ppm CO2)? I think a comparison of such charts (and heck, throw in a +/- variation for solar activity to show how small that is) would go a long way towards explaining things to folks like RSVP... but I've only ever seen charts for the current situation. Basically, a comparison would show how 'back radiation' is increasing and the impact that has on surface heat.
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  36. RVSP,

    There's another part of the story that wasn't brought about so far, which is the energy received by the planet (that's a limitation of a blog debate as compared to a proper class, with a qualified teacher).

    There's the energy received from the sun, and there's the energy emitted by the planet. When both are equal, the system is in an equilibrium.

    The planet always "leaks" (i.e., emits energy). When you increase the CO2 you reduce that leakage. This retains energy, and causes the temperature to rise. This higher temperature, in turn, rises the emmission of energy (the Iout you saw on the mnodel) *until* it is in equilibrium with the received energy again.

    The leakage continues, as always. But now the temperature does not rise anymore, having reached a new balance, in a warmer planet.

    As always, feel free to ask any further questions. As I said, this is my pleasure. But if you have the time or energy for this, I would suggest one of the many tutorials online there are on the subject, for example:

    University of Chicago - the actual classes of the Global Warming Physics basics (for non-science students) on video.

    Online Textbook from the Université Catholique de Louvain, Belgium (in English).

    A slightly different, historical approach, on Spencer Weart's Discovery of Global Warming.
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  37. Alexandre
    This issue can be made as complicated as one wants. On the other hand, one can also construe a model with minimal simplicity for the purpose of making convincing arguments about AGW, or at least leave people with a proper sense of its significance. The way it stands now, with snow blowing in my face every winter, I have to see myself as a frog that needs to jump out of a pot that is going to boiling ever so slowly. Perhaps you can help me ignore the snow, and instead visualize the boiling pot in which I sit. And as you offer to answer questions, I appreciate the offer.

    I asked one question above. It was whether the atmosphere itself acts as a poorer radiator than solids or liquids? (in other words the ground or the oceans)
    And I asked this because this is the only way that the Earth could accumulate more thermal energy.

    (Even then, this piece of data is not sufficient, given that if nights and winters are long enough to allow a complete discharge, this would still have no incremental effect.) In either case, would you know the answer to the question? Thank you.
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  38. RSVP,

    In a sense, yes. Atmosphere is a poorer radiator than solids or liquids. Gases are terrible black bodies and don't emit energy in all the Planck's spectrum as solids and liquids usually do.

    Don't stick so strongly to the analogy, though.
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  39. Alexandre,

    Why thank you! I welcome your assistance, for starters though, let's just begin with ONE formula and as many coefficients as required. Your language suggests you have a superior understanding or was it condescending in nature.

    I would like to find out.
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  40. Let's suppose (in the worst case) every ounce of IR energy were absorbed within a few meters. This would simply raise the radiative heat source a few meters off the ground... or is the energy just going to stay there forever hovering over the ground?

    That would be on average 240 W/m^2. For dry air, it takes ~1,300 joules to raise a cubic meter of air (1.3kg) 1 degree C. So it will take approximately 5 seconds to raise the temp 1 C.

    As the temperature of that cubic meter of air increases, its density decreases and moves the heated volume skyward to be replaced by a lower temp volume of gas (nature abhors a vacuum) and the process repeats. As the volume rises, pressure decreases and so does the temp from PV=nRT.

    It takes energy to move that volume of gas, in fact it takes ~88,000 Watts to move a 1 m^2 column of dry air 1 meter/sec skyward. The Earth only radiates at 240 Watts, which makes sense given that Radiation is the least efficient means to transfer energy while convection is very efficient.

    Entropy states that energy will take the path of least resistance or the most efficient path. Once Convection is no longer available as a means to transfer energy (i.e. Tropopause), then Radiation becomes the only means of cooling.

    Note that the Earth's convection zone, the troposphere, would only be 8 mm high if the planet was 100 meters in diameter. While that is a very short distance, convection moves massive amounts of energy within that zone.

    The wind that drives sailing vessels has huge amounts of force behind it. That energy comes from convection, which comes from the surface heating the air just above it.
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  41. Chris G,

    http://en.wikipedia.org/wiki/Evaporative_cooler
    http://en.wikipedia.org/wiki/Latent_heat

    While it takes 99 joules to raise 1 gram of water 99 C, it takes an additional 2260 joules to get it to change from a liquid to a gas.

    This seems odd given that our oceans are not boiling yet we have a great deal of water vapor in the atmosphere. so let's put it another way. It doesn't not take 2260 joules to vaporize a gram of water.

    The second link provided gives a satisfactory explanation as to why.
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  42. theendisfar,

    I'm familiar with the concepts of evaporative cooling, latent heat, PV=nRT, and all that good stuff.

    However, for instance, evaporative cooling, is a transfer of energy, it does not cause the energy to cease to exist; since the air and water are still both within the earth system, evaporation does not, by itself, remove energy from the earth. And, entropy does not say that energy will take the least resistant path to the exclusion of all others.
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  43. For what it is worth, my understanding is that some of the very early climate models failed to include convection, with the result that arbitrarily high temperatures could come out of them. Indeed, some were even on the wrong side of the triple point of water; it was self-evident that something significant was lacking.
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  44. Chris G,
    I may be wrong but as far as i can remember the first to account for humidity and radiative-convective equilibrium was Manabe et al. 1967.
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  45. Chris G,

    Whether the cooling/heating (transfer of energy) is radiative, convective, or done by evaporation, it is a transfer of energy no less, no energy ceases to exist or is created.

    Evaporation does not remove energy from the Earth's thermo system, however it does transfer ~30 Sextillion (1 Million Trillion) joules (~2300 Joules/gram) away from the surface to the upper Troposphere every ~10 days, Radiation takes over from there. Recall that the Earth's average Surface temp is 14 C and it is reduced to -56 C as convection takes place (PV=nRT) up to the Stratosphere.

    Radiation transfers energy at 300,000,000 meters per sec (speed of light (c)) while convection does it on a much slower, albeit larger, scale ranging from less than 1 m/s to less than 100 m/s.

    Radiation is very quick, but lacks force, convection is very slow but has lots of force. If you look at this from a standpoint of Work it becomes clear that convection does far more work than Radiation within a convective zone. http://hyperphysics.phy-astr.gsu.edu/hbase/HFrame.html

    Any IR "trapped" is literally trapped at the surface. If the IR is trapped at 1 meter, it is at the surface 150 Million times per second, very much like never leaving the surface, at 10,000 meters, altitude of the Tropopause (end of convective zone), it is reduced to 15,000 times, but still very much like never leaving the surface. The IR that escapes directly to space, which is most of it, nearly reaches the orbit of the moon over the same period.

    Knowing that a cubic meter of water at 14 C contains about 1.2 Billion joules, trapping 2 joules/sec amongst the 1.2 Billion will not raise the temp given that it takes around 4.1 Million joules to raise it 1 C. Given the Earth experiences 12 hours of night as well, this bodes poorly for the AGW Theory. (BTW - Is there an actual AGW Theory? Not being crass, just have never seen it described as a Theory like Evolution or Relativity)

    Lastly, you are correct, not to the exclusion, but given two paths, it will take the path of least resistance up to the point where the most efficient is saturated (this happens within millionths of sec over and over again) so Convection and Radiation do occur at the same time within the Troposphere, just more energy is being transfered via Convection. So while CO2 may trap 2 Watts (joule/sec) amongst the billions via radiation, entropy dictates that it will simply use convection or evaporation as a more efficient means to escape instead.

    There are many paths to the Tropopause and only one outside of that.

    Without an atmosphere to convect much of the energy away from the surface, the surface would be much hotter and radiate at a higher energy similar to the moon. A convective zone essentially spreads the energy, that would otherwise all be trapped at the surface (2D), over a larger volume (3D). Increasing volume reduces pressure and temperature.
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  46. Without an atmosphere to convect much of the energy away from the surface, the surface would be much hotter and radiate at a higher energy similar to the moon.

    There's only one problem with this elegant hypothesis: the mean surface temperature of the Moon is colder than the Earth (around -20 C).

    In fact, since the Moon has a lower albedo than the Earth, in the absence of warming by greenhouse gases, the Earth would actually be even colder than that.

    Fortunately for us, CO2, CH4, water vapor, etc. do in fact warm the planet. Otherwise, Earth would be a ball of ice.

    This has been coming up a lot lately, for some reason. I just recently corrected someone else who was making the same mistake here.
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  47. Ned,

    You took the analogy too far and out of context. The Earth and Moon are not compatible with regards to truly making the analogy. My intent was to show that Convection spreads out the energy that would otherwise be trapped all at the surface. Perhaps it was unclear?

    The Moon's surface area is smaller meaning it gets less solar irradiance, and rotates every ~29 days meaning it gets 14 days of sunlight and then 14 days of night. Lastly, the Earth does indeed have an atmosphere, 5,000 Trillion tons of it, 99% N2 and O2.

    Do you take an opposition to any of the substance of what I wrote, or were you just looking for something to quip?

    Fortunately for us, CO2, CH4, water vapor, etc. do in fact warm the planet. Otherwise, Earth would be a ball of ice.

    Not trying to be a denialist :), but none of the above 'warm' the planet. They simply slow the cooling rate. By how much? CO2 'traps' 2 W/m^2. This is a tiny amount of energy as compared to what Convection and Evaporation transfer from the surface to the Tropopause. See above.

    Would you happen to have a link to an actual AGW Hypothesis or Theory? It is quite difficult to refute something that cannot be or has not been described accurately. Perhaps you can expand on your statement if one does not exist.

    Given that Convection and Evaporation exist, how does the GHE slow the cooling of the planet without slowing the Convection or Evaporation rates?

    The GHE is a terrible misnomer. Whatever gets trapped, will simply use convection or evaporation as there is nothing impeding them. Perhaps you take issue with this statement?

    Being new here I should expect some misunderstanding and jabs. Please note, I am a lover of nature, I hike, I camp, and I ALWAYS carry out more trash than I take in. With regards to AGW, it is the scientific method that led me to become a skeptic, not politics. If you think getting clever with me improves your position here, by all means continue, but at least attack the substance rather than picking apart side note analogies.

    With that, no harm no foul. Have a good one, looking forward to your rebuttal.

    The End is Far
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  48. Theendisfar, both of your most recent comments here seem to include a hodgepodge of facts regardless of their relevancy. I would suggest that if you want to engage in a discussion, pick some particular point and try to present it as clearly as possible.

    The comparison of the Moon and the Earth is one example. You originally made the statement "Without an atmosphere to convect much of the energy away from the surface, the surface would be much hotter and radiate at a higher energy similar to the moon." I pointed out to you that in fact the surface of the Moon is colder than that of the Earth, when it should be warmer due to its lower albedo. The difference between the two is the direct result of the Earth's surface being warmed by greenhouse gases. This is not a controversial statement, and in fact has been understood since the 19th century. It's also not a "side note analogy," it's a basic piece of confirmatory evidence that the theory of radiative forcing from greenhouse gases is correct.

    I'm not really sure I understand the point you're trying to make about convection and latent heat. Ultimately, the only way the Earth system gains and loses heat is via radiation. The movement of heat within the climate system is important, and the details get a bit complicated, but they're not really necessary for a first-level discussion of the greenhouse effect.

    If your claim is that the greenhouse effect doesn't exist, you'll need to find someone else to debate that with -- I've just spent the past couple of days here engaging in that argument with another commenter, and I'm uninterested in spending any more of my life right now explaining what from my perspective is very well established, uncontroversial physics.

    Let's see, what else? You ask:

    Would you happen to have a link to an actual AGW Hypothesis or Theory? It is quite difficult to refute something that cannot be or has not been described accurately. Perhaps you can expand on your statement if one does not exist.

    There are many different kinds of scientific theories. If you want to get pedantic about it, the "theory of climate change resulting from anthropogenic emission of greenhouse gases" is very analogous to the "theory of plate tectonics". Both of them developed over a period of time through the contributions of many scientists working in different fields. Neither one can be readily reduced to equations or simple laws, and neither one has a central manuscript along the lines of Einstein's or Newton's papers. Neither one can be completely tested in the lab, though portions of each can be. Ultimately, both theories gained acceptance from the scientific community by combining a convincing theoretical framework with multiple independent lines of empirical evidence. Requests for "a link to the theory of the greenhouse effect" are as much of a red herring as requests for "a link to the theory of plate tectonics". In both cases, if you are genuinely unclear on what the theory involves, you would be better suited to audit some Earth Sciences courses at your local university and/or work through a good, appropriate textbook.
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  49. @theendisfar.

    Aloha. I am not very clever and I won't try to parse words with you. In fact, I will accept your theorem until it is either proved or disproved to our mutual satisfaction.

    First, let us toss out the concept of AGW. Then let us throw out GHE. We don't need them.

    Can you agree that for some reason, 2010 is the hottest year on record?

    Can you also agree that temperature records were set ten times during the past fifteen years?

    And finally, can you agree that these must be cause by something, even if it a completely natural cycle?
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  50. Lots of crowing that the theory of AGW has again been put to death due to patently poor reporting. Plenty of allusions that John was 'fired' from the site he posts on for revealing such earth shattering information.
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