Guest post by Reed Coray
The following example illustrates the issues I have with reasoning often used to argue that increasing the amount of CO2 in the Earth’s atmosphere will increase both the Earth’s surface temperature and the Earth’s atmosphere temperature. Immediately following is a direct quote from URL
http://www.school-for-champions.com/science/heat_transfer_earth.htm
“The present situation is that there has been an increase in infrared-absorbing gases in the atmosphere, such as carbon dioxide (CO2) and methane (CH4). Energy that would normally escape into space is absorbed by these molecules, thus heating the atmosphere and spreading through convection currents. The average temperature of the atmosphere has increased 0.25 °C since 1980, mainly attributed to an increase in infrared-absorbing gases in the atmosphere.”
Although the above statement makes no direct reference to Earth surface temperature, I believe it carries the implication that greenhouse gases in the Earth’s atmosphere increase the Earth’s surface temperature.
I make two comments: the first is relevant only if the above implication is valid, the second is relevant independent of the validity of the implication. First, placing matter adjacent to a warm surface such that the matter is capable of absorbing/blocking radiation to space from the warm surface can lead to a decrease in the warm surface’s temperature. Second, increasing the amount of the absorbing/blocking matter can lower the temperature of the absorbing/blocking material.
Take for example an internal combustion engine whose metal surface is exposed to a vacuum. In addition to doing useful work, the engine produces thermal energy (heat). That thermal energy will produce a rise in the temperature of the engine’s surface such that in energy-rate equilibrium the rate energy is radiated to space from the engine’s surface is equal to the rate thermal energy is generated within the engine. By attaching radiating plates to the engine’s surface, some of the energy radiated to space from the engine’s original surface will be absorbed/blocked by the plates; but because thermal energy can be transferred from the engine to the plates via both radiation and conduction, the temperature of the engine’s original surface will be lowered. This is the principle of an air-cooled engine[1]: provide a means other than radiation of transferring heat from an engine to a large surface area from which heat can be removed via a combination of conduction, convection and radiation, and the engine’s surface temperature will be lowered.
If plates at a temperature lower than the original engine surface temperature are attached to the engine, it’s true that the temperature of the plates will increase to establish energy-rate equilibrium. Once energy-rate equilibrium is established, however, increasing the plate radiating area (adding additional matter that blocks more of the energy radiated from the original engine surface) will likely lower the plate temperature.
Thus, blocking the amount of surface radiation escaping to space does not necessarily increase the surface temperature; and increasing the amount of radiation blocking material does not necessarily increase the temperature of that material. In both cases (the Earth/Earth-atmosphere and the internal combustion engine in a vacuum), the heat eventually escapes to space–otherwise the temperature of the Earth’s surface and the engine would continue to rise indefinitely. The difference isn’t that the energy doesn’t eventually escape to space (it does in both cases), the difference is in the path the energy takes to reach space. The amount of generated thermal energy in conjunction with the path the thermal energy takes to get to space determines temperatures along the path; and adding more material may increase or decrease those temperatures. To say that “Energy that would normally escape into space is absorbed by these molecules, thus heating the atmosphere…” by itself is unwarranted; because an equivalent statement for the case of adding extra plate material to the engine would be “Energy that would normally escape to space from an engine with small attached plates is absorbed by additional plate material, thus heating the plates…” For air-cooled engines, this statement is not true—otherwise the plate surface area of air-cooled engines would be as small as possible.
It’s fairly easy to visualize why (a) adding thermally radiating plates to an air-cooled engine might decrease the engine’s surface temperature, and (b) increasing the area of the radiating plates might decrease the plate temperature. It’s not so easy to visualize, and may not be true, why (a) adding greenhouse gases to the Earth’s atmosphere decreases the Earth’s surface temperature; and (b) increasing the amount of atmospheric greenhouse gases lowers the temperature of the Earth’s atmosphere. I now present one possible argument. I do not claim that the argument is valid for greenhouse gases in the Earth’s atmosphere, but I do claim that the argument might be valid, and can only be refuted by an analysis more detailed than simply claiming “Energy that would normally escape into space is absorbed by these molecules, thus heating the atmosphere.”
If we assume that (a) matter cannot leave the Earth/Earth-atmosphere system, and (b) non-greenhouse gases radiate negligible energy to space, then for a non-greenhouse gas atmosphere the only way thermal energy can leave the Earth/Earth-atmosphere system to space is via radiation from the surface of the Earth. The rate radiation leaves the surface is in part a function of both the area and temperature of the surface. For a greenhouse gas atmosphere, energy can leave the Earth/Earth-atmosphere system to space both via radiation from the Earth’s surface and radiation from greenhouse gases in the atmosphere. Suppose it is true that the density of greenhouse gases near the Earth’s surface is such that radiation emitted from low-altitude greenhouse gases does not directly escape to space, but is in part directed towards the Earth’s surface and in part absorbed by other atmospheric greenhouse gases. As the atmospheric greenhouse gas density decreases with increasing altitude, radiation emitted from high-altitude greenhouse gases can directly escape to space.
Now it’s not impossible that since (a) in addition to radiation, heat is transferred from the Earth’s surface to greenhouse gases via conduction, and (b) convection currents (i) circulate the heated greenhouse gases to higher altitudes where energy transfer to space can take place and (ii) return cooler greenhouse gases to the Earth’s surface, that the process of heat transfer away from the Earth’s surface via greenhouse gases is more efficient than simple radiation from the Earth’s surface. Many engines are cooled using this concept. Specifically, a coolant is brought into contact with a heated surface which raises the coolant’s temperature via conduction and radiation, and the coolant is moved to a location where thermal energy transfer away from the coolant to a heat sink is more efficient than direct thermal energy transfer from the heated surface to the heat sink.
One way to realize increased thermal transfer efficiency would be to use a coolant, such as greenhouse gases, that efficiently radiates energy in the IR band (i.e., radiates energy at temperatures around 500 K). Another way would be to spread the heated coolant over a large surface area. Since surface area increases with increasing altitude, thereby providing expanded “area” (in the case of a gas, expanded volume) from which radiation to space can occur, it’s not clear to me (one way or the other) that greenhouse gases won’t act as a “coolant” reducing both the temperatures of the Earth’s atmosphere and the Earth surface.
[1] It’s true that for most air-cooled engines the main transfer of heat from the engine plates is via a combination of (a) conduction of heat to the air near the plates, and (b) convection that replaces the warm air near the plates with cooler air. To aid this process, a fan is often employed, or the engine is located on a moving vehicle and the vehicle’s motion through an atmosphere provides the flow of air across the plates. Although conduction/convection may be the primary means of heat dissipation from the plates, radiative cooling also dissipates heat.
So, you want to invest resources now in order to solve energy problems beyond 10,000 years.
This isn’t rational.
HenryP writes “The question I have is this: is the (weak) absorption by oxygen/ozone at 14-16 caused by the ozone or by the oxygen?”
I’m hardly an expert! But my interpretation of the “Oxygen and Ozone” components in the diagram would be that the Oxygen is primarily an absorber in the UV range where it disassociates the O2 which reforms to become O3 in some cases and combined they capture even more UV.
And the O3 would be the absorber in the IR range because O2 (and N2) are negligible absorbers in those ranges themselves. So the short answer which should be taken with a grain of salt is O3.
Michael Tremblay;
You seem to hold a misconception that all engines are run by an internal energy source.
???????????
No, I said that the physics in question was reliant upon an external energy source.
Michael Tremblay;
My suggestion was that someone could get out of their scientific ivory tower working with theoretical physics and apply them to a practical purpose by making a physical model to quantify the effect.
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The various examples you provided in your original comment are impossibilities that prove nothing at all in regard to what IS possible in regard to the radiative physics being explained. If you want a physicist to descend from the ivory tower and provide practical examples of physical models, then I would direct you to the multiple examples of same provided by rgbatduke upthread.
Eli writes “When the number density is high enough, essentially direct radiation to space is blocked, the emission from the ghg molecule lower down gets absorbed higher up and does not escape to space.”
I dont think so Eli. Real density matters too not just the proportion of GHGs in that volume except at saturation perhaps.
rgbatduke;
David Hoffer has an even smaller estimate
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Well for clarity, I just note that the IPCC calculates CO2 doubling = 3.7 w/m2 = +1 degree. But they also represent the average temp of earth surface as being 15C. Since it would take 5.5 w/m2 to raise temp from 15C by one degree, these numbers seem to contradict one another. 3.7 w/m2 would raise the temp of -20C by one degree.
Upon investigation, it turns out that the calculation is done not against earth surface temp, but against “effective black body” temp of earth, which as it turns out, is about -20C.
Regardless of how one extrapolates the 3.7 w/m2 modeled at TOA to earth surface, one simply cannot come up with a temp change of 1 degree at surface. It would be more like 0.7 degrees, and my assumption (though I have no way of knowing this) would be that even if feedbacks are positive, they would scale in the same manner at surface.
So… my point is that IPCC numbers, when put into their proper context, do not support +1 degree at earth surface, only +0.7 for doubling of CO2. By extension, feedbacks that would result in 3 degrees at effective black body temp of earth would be more like 2.1 degrees at surface.
Given that the IPCC AR5 is supposedly going to scale back their median estimate even further, to 2.6 including feebacks, my assumption being that this number also is calculated at effective blackbody temps, translates into only 1.8 degrees at surface.
I find that the IPCC documents are consistant in terms of finding the worst possible context to present the numbers, and are extremely vague in that regard to mask the spin they are putting on the issues, and this is a fine example of same. We live on earth surface and that is the temperature we care most about, so those are the number which in my opinion the official literature should be discussing.
davidmhoffer says:
July 22, 2012 at 8:23 pm
The various examples you provided in your original comment are impossibilities that prove nothing at all in regard to what IS possible in regard to the radiative physics being explained. If you want a physicist to descend from the ivory tower and provide practical examples of physical models, then I would direct you to the multiple examples of same provided by rgbatduke upthread.
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That is better than your previous remark. My first remark was an attempt to describe why I have serious doubts about the description of the radiative physics – that being, that if it is as extreme as some people think it is, some engineer would have exploited it to make an engine out of it. My remark was off topic but it did not call for the remark you made.
I might suggest that, if you don’t agree with someone else’s comments, that you either not respond, or respond in a manner which is more constructive rather than insulting and attempting to belittle them. You have to remember that most of the people that follow WUWT are not experts in the various scientific disciplines which are required to understand climatology, and are seeking answers.
I have been following rgbatduke’s threads and find them instructing and helpful. He also exhibits a large amount of patience.
Reed Coray says:
July 22, 2012 at 7:45 pm
Embarassing? Whoever is embarassed by this thread needs to be embarassed more, IMO. While Joel may feel we are sheepherders, he is actually learning too. While Anthony may be embarassed by the passion, what a relief from the political drivel.
rgbatduke,
It might help explaining Greg House that the IR from the colder body is not actually warming the warmer body directly, but rather indirectly by reducing its rate of heat loss. Thereby no thermodynamic law is violated and we can all move on …
Joel Shore:”Are you saying that they are somehow radiating more heat than one would expect given their temperature? Furthermore, the thermal structure of the tropical atmosphere is dominated by convection. The radiative transfer is already such as to maintain a larger lapse rate than exists but convection occurs and reduces the lapse rate approximately to the moist adiabatic lapse rate.”
No, my personal position is that the condensation in atmosphere that causes the lapse rate feedback is also accompanied by *another* negative feedback namely increased cloudiness. Thus, my relationship is increased water vapor leads to lapse rate feedback and (negative) cloud feedback that in turn cause the (near) absence of the tropical hotspot. You, OTOH, argue that if the hotspot is indetectable then the *only* possible interpretation is that there is no lapse rate feedback. I doubt that this is the only interpretation one can draw from the absence of the hotspot but it is possible I am mistaken.
Cheers, 🙂
There have been many interesting comments here, but not a lot of hard facts that support the AGW hypothesis and its proponents like Eli and Joel. Here are a few that do not.
Although AR4 WG1 at FAQ 1.1 (i.e. Trenberth) states that the reason the earth’s surface is as warm as around 14oC “is the presence of greenhouse gases [GHGs], which act as a partial [sic] blanket [sic] for the longwave radiation coming from the surface [OLR]. This blanketing is known as the natural greenhouse effect. The most important greenhouse gases are water vapour and carbon dioxide. The two most abundant constituents of the atmosphere – nitrogen and oxygen – have no such effect…Human activities intensify the blanketing effect through the release of greenhouse gases”, mainly by the combustion of hydrocarbon fuels like coal, gas and oil. That implies there should be an observable reduction in OLR in line with the rising atmospheric concentration of CO2. But the NOAA NCEP reanalysis dataset shows the following UPWARD trend in OLR between 1948 and 2011:
y=0.1369x+226.88
R² = 0.8019
Source: NCEP Reanalysis Produced at NOAA/ESRL PSD at http://www.esrl.noaa.gov/psd/data/timeseries/ Date submitted: 7/16/2012 at 01:53
Similarly, satellite data in 1970 and 2003 showing temperatures (in oK) by altitude over the Tropical Pacific reveal no observable increase at all, in fact the curves and their trends are virtually identical:
1970:y=-6.2945x+300.62
R² = 0.7518
2003:y=-6.296x+300.72
R² = 0.7538
Then there are the trends for the level of water vapor (per cm.) by altitude, which according to AR4 and all should have increased in line with AGW but actually declined between 1970 and 2003, confirming that there was no warming over the tropical Pacific:
1970:
y = -1519.5x + 18498
R² = 0.6781
2003:
y = -1431x + 17219
R² = 0.6162
See the Appendix Tables A1 and A5 in Griggs & Harries (JoC 2007), Comparison of Spectrally Resolved Outgoing Longwave Radiation over the Tropical Pacific between 1970 and 2003 Using IRIS, IMG, and AIRS.
These results appear to confirm the nul that CO2 plays NO role either in reducing OLR or in raising temperatures and water vapor at any altitude (from 1000 hPa to 4.606).
Reed Coray asks
“Under what conditions does the presence of greenhouse gases in the Earth’s atmosphere quit slowing-down outgoing radiation?”
Henry@ur momisugly Reed
First of all they must get the definition of a GHG right. The definition should not be that the substance is a GHG if it has absorption in earthshine wavelengths. The definition must be that if the net effect of more of it in the atmosphere is one of warming, we can call it a GHG. Like in the case of ozone, it has absorption at 9-10 (see your graph that you start of with) and that indeed does leave a dent in earth’s outgoing radiation. So it is classified a GHG. But ozone also deflects a lot of sunlight 0-0.5 um, which is radiation of high energy. I maintain that an increase in ozone (as indeed we are currently observing) will lead to a net cooling effect. My results show earth has started getting less energy exactly since ozone started moving up. So really, they should classify ozone an IHG. (Ice house gas). In fact, oxygen would probably then also be an IHG.
In the case of CO2, its radiative cooling effect and its cooling effect by taking part in photosynthesis cannot be ignored. A paper in in 1974 estimated that about 0.2 -0.3 % of incoming sunlight is consumed by vegetation. With everybody wanting more crops and more trees I am willing to bet that it has gone up substantially since then. I would not be surpised if it is eventually found that the warming effect of CO2 is more or less cancelled out by its cooling effects.
Either way, it has been cooling since 1997 or 1998 even though CO2 has continued to rise. In fact, in Baring (Alaska) it appears to me that CO2 also stopped increasing. Which is all what we could have expected if some people like Hansen and Gore had not jumped on the AGW wagon. There is only GW (CO2 gasses out from the oceans) and GC and until 2045 we are now in GC mode.Sorry. Better get some extra cloths and if you can move to lower latitudes.
http://www.letterdash.com/HenryP/more-carbon-dioxide-is-ok-ok
@ur momisugly Ken Harvey says:
July 21, 2012 at 12:35 pm
Thank you for your kind words sir. 🙂
@ur momisugly Baa Humbug says:
July 21, 2012 at 4:15 pm
I have recieved the file. Many thanks for your help.
I have read it twice and have been confused by some points.
Example: at one point (in a thought experiment) he claims because CO2 can radiate it will cool down to 0K.
It seems to me that CO2 can only cool to 193K and then need help from other gases that can radiate below that temperature level.
Musn’t discuss that here though, a bit OT.
Eli Rabbet: “Clever enough :), but the sun is a plasma, not a gas and in any case you would need some gravity to hold the damn thing together”.
But the National Radio Astronomy Observatory guys say that all matter emits thermal radiation, be it a lump of stone or iron, plasma or gas because charges are moving in relation to one another. As a gas has molecules and they contain a charge( protons and electrons), then as the molecules jostle about, the charges in one molecule move in relation to other molecules. In the case of a plasma the charges are free and this emission is called “Free-free emission”. This has nothing to do with absorbtion bands of molecules. The radiation emitted is broadband and is called blackbody radiation. At 15c the infrared radiation emitted peaks at 10.1um.
The National Radio Astronomy Observatory explanation:
http://www.nrao.edu/index.php/learn/radioastronomy/radiowaves#blackbody
@ur momisugly rgbatduke:
Thank you for your patience and descriptions of radiative transfer. (ps – forgive my apparent ‘misspellings’ – I use Canadian English)
A lot of my problems with the concepts of radiative transfer come from misunderstandings. For example; the entire effect is labeled the Greenhouse Effect (GHE), whereas it has very little to do with how a greenhouse works actually works; Greenhouse Gases (GHG) are defined as those gases which absorb Infrared Radiation (IR) which is only a small portion of the entire spectrum of Electromagnetic Radiation (EMR) which covers all of radiative energy. IR is directly associated with heat when it is only a form of radiative energy which is emitted by objects within the temperature range that fall within the IR spectrum. Finally, with Colour Temperatures (an aesthetic description), red is considered a warm colour while blue is considered a cold colour – in direct opposition to their respective energy levels and temperatures. I think that these basic misunderstandings are true for a lot of people, including well educated scientists.
I thank God for the so-called GHE, since without it Mankind would not exist. Rather than call it the GHE though, I would rather call it the Atmospheric Effect (AE) since I believe that the protective effect of the entire atmosphere is far more important than the effect of GHGs.
First, it is important to remember that most of the theoretical discussions I have encountered only consider that the atmosphere is mixture of gases. As you are certainly aware, this is not true. The atmosphere can more accurately be described as a mixture of gases with suspensions of liquids and solids. Most people assume that clouds are water vapour, again, this is not true. Clouds are suspensions of liquid and solid water in the atmosphere – water vapour is completely transparent, if you can see it it is either liquid or solid. Liquid water and solid water have completely different radiative absorption and emission properties, as well as reflective properties, for the entire solar spectrum when compared to water vapour. As a retired Steam Engineer, I have an appreciation for the thermodynamic properties of water which, I suspect, is far greater than most climatologists – It takes a lot of energy to convert water from one phase to another and when it reverts from gas to liquid to solid it releases a lot of energy, a property which makes it among the best for converting energy into work.
The atmosphere also has other suspended liquids and solids within it which can also have an effect on the reflective, scattering, and absorptive properties for radiative energy. Most of the descriptions of these effects are lumped together by those people creating climatic models as a variable in order to ‘accurately’ model their effects, but for the most part these variables are guesses and increase the inaccuracy of the model depending on their interpretation (sensitivity?).
I followed the link to Dr. Spencer’s site (http://www.drroyspencer.com/2010/07/yes-virginia-cooler-objects-can-make-warmer-objects-even-warmer-still/) and I understand the concept that a ‘cooler’ object can ‘make warmer objects even warm still’. I have a problem with his experiment when it relates to the Earth’s atmosphere. His ‘hot’ plate is constantly radiating at 150F because it is having energy constantly applied to it. This only occurs to the Earth during the daytime (with energy coming from the Sun), so if the experiment is accurate, the Earth’s surface temperature will increase due to the radiative effect of the atmosphere during the day or if the temperature of the atmosphere is higher than the Earth’s surface. At night the temperature of the Earth’s surface will decrease, and the atmospheric temperature will increase, until they reach thermal equilibrium. I believe that the real AE at night is that the RATE of energy transfer is reduced, not that the atmosphere is warming the surface due to back radiation.
Another problem that I have with climatologists’ interpretation of the AE is that they forget that the atmosphere also reduces the RATE at which the Sun heats the Earth. During the daytime, radiative energy is intercepted (absorbed) by the Earth’s atmosphere. Oxygen, Nitrogen, and Ozone (non-GHGs) absorb EMR at shorter wavelengths and use this energy to split the molecular bonds of O2, N2, and O3 while at the same time the energy is converted to heat when the molecular bonds reform – one of the (theoretical) reasons the Stratosphere is warmer than the upper Troposphere. If this shortwave radiation reached the Earth’s surface it would ionize molecules and atoms at the surface and be absorbed by the solid and water surfaces and converted to heat, raising the surface temperature even further. As far as I am concerned the daytime AE is far more important since if you can reduce the rate of heating it doesn’t matter if you reduce the rate of cooling. I know that this radiation is not IR, but since shortwave radiation has much more energy than IR, isn’t the absorption of high energy EMR (UV) more important than the absorption of low energy EMR (IR) in order to prevent a rise in temperatures?
Finally, I would like clarification on this point – If a CO2 molecule (or any molecule for that matter) is absorbing a photon of a specific frequency and re-emitting a molecule of the same frequency, where is the energy transfer? From my perspective, in order for there to have been an increase in temperature (heat energy) or in kinetic energy, the emitted photon has to be at a lower frequency – what is really happening when a gas molecule absorbs a photon?
Eli Rabett says:
July 22, 2012 at 6:59 pm
David asks
So my questions are as follows. How much of the non GHG energy is radiated to space via collision with GHG molecues?
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Eli says…
Essentially all of the IR radiated to space from the atmosphere is a result of collisional excitation of vibrational modes.
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My response… First thank you for engaging my questions. But, is not some of the energy radiated to space, first recieved, not by conduction, but by radiation in the correct WL?
Question two
If the GHG molecues were not present, how much longer would this energy stay within the atmosphere if it could only be conducted and convected about, but not radiated to space?
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The atmosphere would be much colder because the surface would be colder (somewhat technical argument related to the derivation of the adiabatic lapse rate starting with an average surface temperature). If you allow no ghgs, there would be no water vapor or clouds.
You can get an idea from this figure. Everything below the 320 K line is a result of ghgs re-radiating after collisions.
You raise the interesting question of what the energy of such an atmosphere would be. The temperature at each level would be given by the dry adiabatic lapse rate, the energy per unit volume given by CvT. where Cv is the effective specific heat.
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Thanks again Eli, but I think you did not answer my question. With an equally dense, non GHG atmosphere, would it not be more transparent to incoming, and not just outgoing TSI, and therfore would not the surface insolation be higher? Of couse the non GHG on a water planet would be impossible, becuase the increases surface insolation would clearly lead to increased W/V. but, for the sake of a thought experiment, let us assume no increased W/V., but equally dense atmosphere. Would the surface T not rise higher in relationship to increased surface insolation? Would the surface not lose energy by both conduction to non GHG molecues, as well as through radiation to space, admittedly zipping past the non GHG atmosphere to space? However, any energy which conducts (not radiates past) to a non GHG atmosphere must stay in that atmosphere longer then it would in a GHG atmosphere, as they only way such an atmosphere can lose energy is by conduction to the surface where from there it can radiate to space. So my question remains unanswered, but it appears logical to me that GHG slow the loss of raidated energy from the surface, but accelerate the loss of conducted eneregy from the surface. I was hoping to see the ATMOSPHERIC residence time of CONDUCTED energy from the surface compared to a non GHG atmosphere verses a GHG atmosphere. I inderstand that radiated energy has a shorter residence time in a GHG world, but I suspect that conducted energy has a longer residence time in a non GHG atmosphere. I would like to see this quantified.
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My next question
<i.And, as additional GHG molecues speed the escape of conducted Non GHG energy, would not this reduced residence time of conducted non GHG energy have to be subtracted from the increased residence time of IR energy raqdiating from the surface, and backradiating from the GHG molecues? TSI incoming is a consistent flow, so the energy gained or lost by either radiating conducted non ghg energy out, or keeping surface energy within the atmosphere is porportional to the residence time of the energies affected.
————————————————————
Eli answers…
This is somewhat backwards. GHGs (and increases in same) SLOW the escape of IR energy from the Earth surface and atmosphere together. Without GHGs the escape of IR energy from the surface is much faster, and if you look at energy balance, the speed up exactly matches the deficit from wiping out the ghgs.
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Thank you, but again I think you are not answering my question. I would like to first correct your above statement. Wherever you say "IR energy" please change that to RADIATED IR energy and we have no problem. However my question concerned the atmospheric residence time of CONDUCTED surface energy. The surface, when it is losing heat, is all the time losing heat by radiation and conduction. The atmosphere can only lose heat to space by radiation. A non GHG atmosphere must therfore have a longer residence time for conducted energy then a GHG atmosphere.
trccurtin,
You said:
“That implies there should be an observable reduction in OLR in line with the rising atmospheric concentration of CO2. But the NOAA NCEP reanalysis dataset shows the following UPWARD trend in OLR between 1948 and 2011”
Yup, both the NOAA Interpolated, ISCCP-FD and ERBE data show increasing rather than decreasing OLR at TOA during the modern warming era. If there has been no increase in the energy input (from the sun) during this period, then this is the direct opposite of what one would expect. There is no real sign at TOA that we’re strengthening the insulating power of the troposphere. It’s nice to hypothesize about what should and could occur if so and so, even with sound, coherent physics and numbers to back up your theory, but once in a while it’s a good idea to take a look out your window to verify if your isolated process has or has not a detectable NET effect on the actual, real-world system. If not, but you’re still confident that it must be real, then it means it’s not alone. There are forceful counter-effects and/or the show is actually run by different and much more potent processes, totally overwhelming it.
If there HAS been an increase in energy input (which the observations suggest), then THIS is the cause of the warming and the increased OLR at TOA simply Earth’s lagged response.
Kristian says:
July 22, 2012 at 10:22 pm
It might help explaining Greg House that the IR from the colder body is not actually warming the warmer body directly, but rather indirectly by reducing its rate of heat loss. Thereby no thermodynamic law is violated
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Yeah, I know this narrative, I formulated the problem both ways a few times.
The warmists problem is that they can not produce any real genuine falsifiable scientific experimental proof of that “reducing its rate of heat loss”. They just keep “explaining”, rephrasing and mostly suggesting I should prove their claim.
Michael Tremblay says:
July 23, 2012 at 1:04 am
I followed the link to Dr. Spencer’s site (http://www.drroyspencer.com/2010/07/yes-virginia-cooler-objects-can-make-warmer-objects-even-warmer-still/) and I understand the concept that a ‘cooler’ object can ‘make warmer objects even warm still’. I have a problem with his experiment when it relates to the Earth’s atmosphere. His ‘hot’ plate is constantly radiating at 150F because…
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No, there was no hot plate and there was no experiment. It was a fictitious experiment with fictitious plates, fictitious temperatures and fictitious conclusions. All fiction, nothing real. The problem is many readers think it was real, because otherwise it would have been outrageous to present that as science, so people subconsciously rule this option out and just BELIEVE.
Joeldshore writes “In other words, the effect of lower temperature is about 300X as important as the effect of increasing surface area.”
I think this is incorrect Joel. Surely it has nothing to do with surface area and instead has to do with CO2 concentration at that altitude. If the CO2 levels increase then, at the average radiating altitude there will be more CO2 and hence more energy is radiated.
If you say that the altitude has to increase because more CO2 above “captures” the radiation then that is a statement and not a fact. If you only use models and theory to back up that statement then you’re not making a satisfactory scientific argument.
paulinuk says: July 23, 2012 at 12:17 am
“But the National Radio Astronomy Observatory guys say that all matter emits thermal radiation …
True enough, but this is where you need deeper knowledge. They also say only a theoretical “black body” emits as well as possible; all true materials emit less well, and they emit differently at different wavelengths. It turns out (for reasons that are theoretically well understood) that CO2 (and all molecules with at least 3 atoms) will emit certainly wavelengths of IR quite well, but emit other wavelengths EXTREMELY poorly. It also turns out that symmetric diatomic molecules emit EXTREMELY poorly at ALL IR wavelengths.
Yes, if you look closely enough you can find IR from room temperature N2 and O2, but it is orders of magnitude less intense than the IR from CO2, O3, CH4, etc.
Greg House says: “so people subconsciously rule this option out and just BELIEVE.”
Yes. In the same way that I rule out the option that the next time I drop a rock it will fall UPWARD. I “just BELIEVE” it will fall downward. If I do a “fictitious experiment” and say “suppose I let go of a rock in mid air ..” we don’t need to say “Which rock? Have you tested THAT rock before to make sure it will fall? Have to dropped it lots of times to see if it falls every time?”
Science is about finding consistent rules that accurately predict what will happen, based on previous experiments. So I don’t HAVE to do every possible variation of an experiment to be quite sure of the outcome.
Thousands (millions!) of experiments have measured the nature of electromagnetic radiation.
Thousands (millions!) of experiments have measured the IR properties of gases.
Thousands (millions!) of experiments have confirmed the laws of thermodynamics.
It would be perverse to expect a rock to disobey well-established rules of physics and suddenly fall upward.
It would be perverse to expect the hot-plate, etc. to disobey well-established rules of physics and suddenly quit conducting/convecting/radiating in the expected manner.
Sure, it would be nice to have a specific experiment measuring a specific hot plate, but thousands (millions) of practical devices operate every day within the rules of physics, and engineers don’t have to wonder about every device they design, worrying that the laws of physics might not apply.
Tim the Toolman says: “If you only use models and theory to back up that statement then you’re not making a satisfactory scientific argument.”
But don’t you see, you ALSO were only using “models and theories” when you assumed that “If the CO2 levels increase then, at the average radiating altitude there will be more CO2 and hence more energy is radiated.” I think that Joel is right that the average radiating level will rise — there are lots of analogies that would lead to this conclusion (not to mention hard math and physics). Your model seems to be that “average radiating height” is a fundamental feature of the earth, independent of where the molecules emitting the IR radiation are found.
And in my book, “using theories” is a VERY scientific approach to trying to discern what will happen. (Of course, that assume you have a solid grasp on the theories so that you can reason out what they are telling you.)
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davidmhoffer says:
July 22, 2012 at 8:41 pm
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Funny that joelshore and the rabbit aren’t addressing your important point. Apparently they don’t want to go there….
Reed Coray says:
July 22, 2012 at 7:45 pm
I asked the question “Under what conditions does the presence of greenhouse gases in the Earth’s atmosphere quit slowing-down outgoing radiation?” As far as I can tell I never got an answer to that question. So to those who believe/claim (a) and (b) above, I repeat the question. If the answer is: “As long as there are greenhouse gases in the atmosphere, they never stop ‘slowing down’ outgoing radiation”, then I’d appreciate an answer to the obvious follow-up question: “If (a) the presence of greenhouse gases in the Earth’s atmosphere doesn’t change the rate radiation (energy) is absorbed by the Earth/Earth-atmosphere system, (b) in the absence of greenhouse gases the energy-rate equilibrium temperature is T, and (c) greenhouse gases always ‘slow down’ outgoing radiation which causes the temperature to rise, then why doesn’t the temperature increase without bound (or at least until the greenhouse gases go away or the temperature changes so that the temperature is high enough that radiation from the Earth/Earth-atmosphere is negligible in the greenhouse gas absorption bands)?”
Because the outgoing radiation increases as the fourth power of temperature whereas the effect of CO2 is logarithmic. Consequently the stationary point where incoming energy equals outgoing energy goes up but with bounds.
rgbatduke says:
July 21, 2012 at 11:31 am
Thus, if you increase the levels of GHGs, the Earth will now be emitting energy at a slower rate than it is absorbing energy. This causes the Earth to warm…In fact, it warms until the radiative balance between emission and absorption is re-established.
The problem is that it doesn’t “cause the Earth to warm”. The sun causes the Earth to warm, almost exclusively. The GHE causes the Earth to lose heat from the Sun more slowly and hence be warmer than it would have been without it.
Sorry to be picky, but half of the debate is people who do not understand that what you mean — and what a world of climate scientists mean — is not the literal meaning of the words you say. GHGs do not warm anything.
Robert I agree with most of what you say but since you are being picky I’ll reciprocate. GHGs do warm something, they warm the atmosphere.