Talk:Greenhouse effect/Archive 1

message: The paragraph in the section titled "Real green house" is the most stupid and unscientific statement I have ever seen. The foundamental principle is how the glass let radiation (e.g. ultraviolet, visible light) in and then after the energy is converted into another form (e.g. infrared), the glass don't let it out.  The basic principle was dismissed by a ridiculous claim that, when you open the window the greenhouse won't work.  Hence it was concluded that the greenhouse works on the principle of convection.  Such conclusion is really laughable.  When you open the windows, you introduced the convection that carried the heat away.  It does not prove that the greenhouse works by convection, you can only claim that the greenhouse is ruined by convection.  The better set of experiments is as follow:
* eliminate the radiation and conduction from the greenhouse
:built a greenhouse with insultated, oplaque walls and roofs and see how the heat get in without conduction nor radiation.
* eliminate the conduction and convection from the greenhouse
:built a greenhouse with doublepane glass and no windows and see how the heat build up without conduction or convection.
* eliminate the radiation conversion that is the main principle of greenhouse effect.
: built a greenhouse as the last one, but coat everything inside the greenhouse with mirror surface and then measure how the greenhouse does not work when there is no infrared to trap by the glass. 
The argument about the opening window is flawed because when you open the window, you are looking at a totally different system, instead of just the greenhouse's relation with the sun, you are looking at the greenhouse plus the surround air.  If you want to compare the earth to a glass greenhouse, then you cannot open the window to vent the hot air, because you can put a giant tube that poke into outter space and pump the hot air away, you can stop the global greenhouse effect just like you open the windows of the glass house.  On the other hand, if you can build a large enough greenhouse where its roof is above the atmosphere, then whether you open the window on the roof or not will make no difference to the temperature inside the greenhouse.  Therefore the global and glass greenhouse work the same way except that the convection effect overpowers the greenhouse effect when you have a small glass house.
Kowloonese 23:10, 5 Nov 2004 (UTC)
replies: text: (William M. Connolley 11:36, 6 Nov 2004 (UTC)
replies: text: I was indeed referring to the flawed Wood's experiment.  He wrote a paper, you don't have to agree, do you?  Kowloonese 08:47, 8 Nov 2004 (UTC)
replies: text:  (William M. Connolley 09:28, 8 Nov 2004 (UTC)
replies: text: The argument about the opening window is flawed because when you open the window, you are looking at a totally different system, instead of just the greenhouse's relation with the sun, you are looking at the greenhouse plus the surround air. That's right. It is a different system. Exactly as a fanciful "pipe out to space" would make a totally different system: earth plus surrounding space insteads of just earth. In other words, the analogy in the article is entirely appropriate. Tannin 09:46, 8 Nov 2004 (UTC)
replies: text: Scientific works are subjected to peer reviews.  The Wood's experiment reads like baloney to me, though I am not his peer.  What is the general acceptance of his conclusion in the scientific community?  Anyone who has studied history of science knows that many convincing scientific theories were later proven wrong.  This one is not even convincing.  Why is his view stated like the gospel in this encyclopedia?  It is definitely not NPOV.  Kowloonese 21:34, 8 Nov 2004 (UTC)

text:  (William M. Connolley 22:17, 8 Nov 2004 (UTC)

text: I have a ridiculous argument that this analogous to the open window argument by Woods.  Here it goes, prepare to laugh.  I can prove that penicillin is not a cure for bacterial infection because if I cut open the patient's artery, the patient dies.  The open window green house is as silly as this. It just does not make sense at all.  Kowloonese 21:49, 8 Nov 2004 (UTC)
replies: text:  (William M. Connolley 22:17, 8 Nov 2004 (UTC)
thread_title:  Real green house 

message: I found a good article .  It may be worth reading before this page is getting way too long.  Kowloonese 21:01, Mar 3, 2005 (UTC)
:An interesting read.  :)  I was going to suggest there should be a wiki page, but there already is.   — Cortonin | Talk 05:20, 4 Mar 2005 (UTC)
thread_title:  When the discussion is going nowhere ... 

message: I don't endorse the way WMC and Cortonin are gaming the system.  One reverts 4 times in 23.8 hours, the other reverts 4 times in 26 hours.  The 3RR is not a game, it's not a right - it's a limit on bad behaviour.  I don't think that 26 hours is any better than 24.  They can both return to their revert war tomorrow.  Guettarda 20:24, 14 Apr 2005 (UTC)
replies: text: Maybe you could try editing by the content rather than editing by the people.  Let's not lose sight of what the goal of this whole project is supposed to be.   — Cortonin | Talk 22:33, 14 Apr 2005 (UTC)
replies: text: True, that would be preferable.  Can you find someone who supports your interpretation of the physics here, someone who can argue the case without the baggage that you (and William, in fairness) bring to this issue?  Guettarda 00:01, 15 Apr 2005 (UTC)
replies: text: That comment is still editing by the people.  These are simple issues which can be edited without all the interpersonal melodrama and taking of sides.  It's not even an environmentalist issue, and has nothing to do with advocacy or opposition to any environmentalist position, but still all the environmentalists who edit here are clumping together, perhaps out of habit.  This is simply about describing the physical mechanism for how a gardening greenhouse works.  If you want to understand the mechanism in detail, read Joliet O, et al., Agricultural and Forest Meteorology 55(3-4): 265-294 Jun 1991.   — Cortonin | Talk 00:28, 15 Apr 2005 (UTC)
replies: text:  (William M. Connolley 21:56, 15 Apr 2005 (UTC)
replies: text: I already explained to you on Talk:Solar greenhouse (technical)#Atmospheric Convection why your belief that it is unrelated is incorrect and based on a significant misreading of the paper.  It in fact, directly addresses and describes the full mechanism.  That its description is complete is confirmed by its strong predictive correspondence to experiment for various greenhouse types and conditions.  Anything additional is a small minor effect, or not confirmed by experiment.   — Cortonin | Talk 22:18, 15 Apr 2005 (UTC)
thread_title:  My revert 

message: Vsmith, I appreciate you taking the time to consider the merits of the individual aspects of part of the edit.  I am removing the portion that says "within the atmosphere", because that seems to be implying some sort of horizontal convective flow changing the average temperature.  Horizontal convective flow would only minorly affect the average temperature, but since thermal IR scales with the fourth power, horizontal convective flow could actually decrease radiative loss and thus increase average temperature.  For example, [(280^4-260^4)+(270^4-260^4)]/2 > 275^4-260^4.   — Cortonin | Talk 18:16, 23 Apr 2005 (UTC)
replies: text: At first I thought the "within the atmosphere" was rather redundant and obvious, but the wording "through the thermal IR absorbence of the atmosphere" seemed to imply out of the atmosphere although I assumed that was not the intent. As to horizontal convective flow, that is a most important part of the convective heat energy redistribution within the atmosphere even though it may have only a minor effect on the global energy balance total. Hadn't considered the horizontal component as a significant factor in decreasing radiative loss, more to think about :-) Vsmith 23:10, 23 Apr 2005 (UTC)
replies: text: Right, it's an important part of the redistribution, but in general, horizontal convection's contribution to the average temperature should be a slight increase.  (It should be possible to construct an area where horizontal convection would decrease the the average temperature of that area, if the right surface materials were chosen, but on average, the result should be an increase to the average temperature for the reason given above.)  I saw what you were doing with the "partly above" to imply not leaving, and this is a good patch.   — Cortonin | Talk 02:54, 24 Apr 2005 (UTC)
thread_title:  Atmospheric convection 

message: Perhaps someone can clarify in what way a garden greenhouse is different from the global greenhouse?  There seems to be disagreement about whether a single factor is overwhelmingly dominant.  Firstly, can you identify the differences?  Secondly, why does it matter?  Can we just say "The analogy is flawed by oversimplification and the differences are:…" ? (SEWilco 05:23, 3 May 2005 (UTC)
replies: text: (William M. Connolley 19:22, 3 May 2005 (UTC)

text: (William M. Connolley 18:18, 5 May 2005 (UTC)
replies: text: You're confusing cause and effect.  Opening a window only has a significant effect because the greenhouse is already far above the ambient temperature due to thermal IR absorption.  You say you're a mathematician by training, so perhaps somewhere along the line you ran into the difference between the inverse and the contrapositive.  The inverse does not logically follow from the original statement, and you're trying to use argument by inverse as a proof method here with the window opening line.  It's just faulty logic, from basic logic theory.  You're saying "opening a window lowers temperature" implies "closing a window raises temperature", which is argument by inverse, and is incorrect logic.  The correct statement is the contrapositive, such that "opening a window lowers temperature" implies "higher temperature means the window is closed".  That's all.  It doesn't yield ANY information about how the higher temperature is obtained, because there is no causal connection in the reverse direction.  This is not "perspective" or "point of view", it's basic logical reasoning.   — Cortonin | Talk 21:03, 5 May 2005 (UTC)

text: For a qualitative (and quantitative) comparison of the contributions of convection and radiation in the literature read Joliet O., et al.; Horticern - An Improved Static Model for Predicting the Energy-Consumption of a Greenhouse, Agricultural and Forest Meteorology 55(3-4): 265-294 Jun 1991, A detailed explanation of the gardening greenhouse mechanism.  Also, there is significantly more discussion at Talk:Solar greenhouse (technical) about the mechanism of gardening greenhouse operation.   — Cortonin | Talk 10:31, 3 May 2005 (UTC)
replies: text:  (William M. Connolley 19:22, 3 May 2005 (UTC)
replies: text: For credibility's sake, you really should check the paper again more carefully before you keep repeating that.   — Cortonin | Talk 21:21, 3 May 2005 (UTC)
replies: text:  (William M. Connolley 18:31, 4 May 2005 (UTC)
replies: text: Perhaps I "failed to understand" what you think it says because I read the whole thing, and noticed the section conspicuously labelled "exchange between inside and outside air", the accompanying equations, the graph which it is stated includes air infiltration between the inside and outside, and the total of fourteen references to air infiltration between the inside and outside sprinkled throughout the article.   — Cortonin | Talk 06:31, 5 May 2005 (UTC)

text:  (William M. Connolley 18:18, 5 May 2005 (UTC)
replies: text: Hypothesizing contributions which are not measured and not required by the model, but which you think would be there if they were allowed to does not make sense.  See Occam's Razor.   — Cortonin | Talk 21:03, 5 May 2005 (UTC)
replies: text: Cortonin, you have just answered any questions I had re: the Hortichem paper that I don't have access to. It is obvious from your comment above that, like all glazing researchers, they start from an isolated system and do not consider real convection. Occam's razor does not apply when you are dismissing factors that haven't been tested and simply ignored by the model or defined away. The major factor is blocking of convection, And all of your references and thermodynamic equations simply ignore that and start from the given that convection is blocked. You have totally convinced me and removed any doubt I had, thanks. -Vsmith 23:21, 5 May 2005 (UTC)
replies: text: I think you completely misunderstood what I typed.  I said "contributions which are not measured" meaning "contributions which are not observed," not "contributions which are not looked for."  The Horticern paper DOES EXPLICITELY include convection from the inside air to the outside air in their model, and does explicitely make measurements which include the contributions from this convection.  Convection HAS been tested, HAS been incldued in the model, and has NOT been defined away.  I don't think I can say it any clearer.  Please don't make any assumptions that are opposite to this unless you have read the paper yourself, because I assure you it is explicitely included, and I have pointed out precisely where in the paper.   — Cortonin | Talk 04:51, 6 May 2005 (UTC)

text: (William M. Connolley 19:22, 3 May 2005 (UTC)
replies: text: Actually, we're talking about both.  Both global and gardening greenhouses spend 50% of their time during the night.   — Cortonin | Talk 21:21, 3 May 2005 (UTC)

text: SEWilco, you are right that the nighttime provides the most clear test of thermal IR.  As far as the equations are concerned, day and night are exactly the same, except that day has an input flux of solar energy.  But both day and night experience the same equations for thermal loss by convection, conduction, infiltration, and radiation to the sky.  For understanding the significance of the radiative contribution, it's important to keep in mind that the radiative sky temperature is on average somewhere around 16C cooler than the ambient temperature, so radiative exchange with the sky is like keeping an ice pack on your head.  This is precisely why the temperature drops so quickly on a clear night.  A greenhouse, however, does not experience this drop, even though the environment right outside of it does (and the same heat loss happens continually throughout the day too).   — Cortonin | Talk 21:21, 3 May 2005 (UTC)

text: And regarding the IR cameras, that won't work.  Those cameras view NIR (near-IR), and not thermal IR.  Check infrared for a description of the subbands of IR, and check Wien's displacement law for a description of how to calculate the wavelength of thermal radiation at a specific temperature.  (Room temperature is about 10µm).   — Cortonin | Talk 21:21, 3 May 2005 (UTC)
thread_title:  Differences in scale 

message: I have done a preliminary read of the Horticern paper by Jolliet et. al. (Agricultural and Forest Meteorology, 55, 1991, 265-294). Thanks Cortonin. It is a very detailed report of investigations of greenhouse efficiency and a computer model. The research was done on a large commercial working greenhouse. The greenhouse environment was of course enclosed. The bulk of the report is not really applicable here. Again I have not fully digested the whole thing, but one quote seems to be immediately of interest here. 
:"The energy loss due to air renewal by infiltration represents about 20% of total losses and depends on the quality of the joints, cladding area, windspeed and inside-outside temperature difference." p.274.
If within a closed greenhouse environment some 20% of energy loss is due to infiltration or convection through leaks and unsealed joints, that speaks volumes about the importance of convection blocking to the maintaining of the heat from captured solar energy.
::Bear in mind that this is describing energy loss, not energy not-lossed.  Part of the big problem here, is that people are trying to describe the greenhouse in a language of not-exchanged energy, which is a fictional concept not present in thermodynamics, and is resulting in much confusion.  Thermodynamic systems must always be described in terms of what IS happening.   — Cortonin | Talk 05:31, 10 May 2005 (UTC)
replies: text: What 'is happening is that a bubble of warm air, which is out of equilibrium with its surroundings, will convect away. The first and most basic function of a greenhouse is to enclose that warm bubble so it doesn't immediately convect away and the heated air is held within the volume of the greenhouse. Once that convection-blocking step occurrs then we can worry about better glazing and insulating materials to keep the heat trapped longer. And this is where all of your glazing research papers come in to play - after the bubble is trapped. As to "what IS happening", what is happening is that the bubble of air is first isolated and then the glazing people go to work to improve the energy retention within the trapped bubble. But, first you have to trap it :-) Vsmith 15:52, 10 May 2005 (UTC)
replies: text: Let's go back to your little valley for a moment.  Take your little valley at night, where the surface temperatures are cool, and the air above that it is warmer.  In this situation, increased convection is increasing the temperature of the surface.  Similarly, if you put a greenhouse in that valley without considering radiative blocking, that greenhouse will become cool just like its environment, and the convection with the air above will be actively attempting to warm the greenhouse.  Blocking that convection then by a wall around the greenhouse will only stop that warming, making the inside of the greenhouse slightly cooler than the outside environment which receives that additional warming from the air above, right?  Have you considered this?  "Convection suppression" does not always warm.   — Cortonin | Talk 17:16, 10 May 2005 (UTC)
replies: text: Excuse me - "Convection suppression" does not always warm. In my view convection suppression essentially never warms, and neither does the glazing. The heat comes from the incoming solar energy. A greenhouse simply acts to hold onto that heat a bit longer, mainly by blocking convection and then to a perhaps lesser extent by absorbing or blocking outgoing IR. Your analysis of valley convection is absurd - warm air above does not sink into the valley and displace the cold surface air - density diffs. drive convection and warm low density air doesn't sink and push cold dense air up. Vsmith 20:30, 10 May 2005 (UTC)
replies: text: The glazing does not independently produce heating, but it does actively block a constant cooling.  The radiative sky temperature is on average around 16C below the temperature of the outside surface environment (about 26C below on clear days and about 6C on cloudy days).  By comparison, the air being exchanged by convection is very close to the same temeparture as the surface temperature, sometimes less, sometimes more (although yes, convective flow is higher when the surface air is warmer than when temperature inversion occurs).  Now, let's consider a simple little situation right after the sun goes down, and let's say we have a greenhouse starting out at this time at the same temperature as the outside environment.  By the "convection suppression" theory, the temperature should stay about the same as the outside, since there is no sunlight coming in, and there is very little convection outside because the air above the ground is actually hotter, reducing convection (although we have no idea why it's hotter under the "convection suppression" theory).  By the thermal IR glazing theory, the temperature inside the greenhouse will be hotter than the outside by the end of the night.  The greenhouse won't get any hotter than it was when it started, but the outside environment WILL cool off substantially by radiative exchange with the upper sky, which is significantly cooler than the surrounding environment.   — Cortonin | Talk 03:36, 11 May 2005 (UTC)
replies: text: Now, in reality, the second one is what actually happens.  The greenhouse maintains its temperature, and the outside environment cools off.  So if you want to know why a greenhouse is hotter, you have to examine why the outside environment loses its energy when the greenhouse does not.  So let's try to examine this in terms of convection:  The outside world shouldn't lose energy like that.  We know that for a distance the temperature gets hotter at night as you move above the ground, and as you say, there is also less convection, and what air exchange there is results in the air above actually warming the ground.  Now, let's try to examine this in terms of radiative exchange:  The radiative temperature of the upper sky is quite cool, as measured with infrared thermometers, and thermal IR is going back and forth bringing the surface into equilibrium with the upper sky.  We know that this cooling effect is significant enough to notice, as everyone reading this has felt it at some point in their life.  We also know that the upper sky is similarly cool during the day time, and so we also know that the radiative exchange is occurring just as strongly throughout the day.  So in the outside environment, solar energy is pumped down and radiated back up throughout the day, and continues to radiate throughout the night.  In the greenhouse environment, solar energy is pumped down and almost none of it radiates away, day or night.  To explain why the greenhouse is warmer, you must explain why the outside world cools off at night.  I challenge you to try to find a reason for that in terms of "convection suppression".   — Cortonin | Talk 03:36, 11 May 2005 (UTC)

text: The units are not sq.m./sq.m., and it does not describe the fraction of window exposed.  It instead describes the "air infiltration per unit area of cladding".  A more reasonable value for an open surface would probably be 0.0053, as is given in the paper for the open ventillator term.   — Cortonin | Talk 05:31, 10 May 2005 (UTC)

text: "As it emphasizes by what it leaves out, the importance of convection blocking"?  Are you listening to yourself?  The paper describes the mechanism of actual greenhouse operation, and compares it to experiment, showing where all the energy flows, and you say that it fails because it doesn't describe it in terms of how you think it operates?  There's a bit of logical error in the reasoning there...  If you manipulate those equations to consider an environment with no covering, and only unblocked radiative exchange with the sky and open convection through the same area with an environment of the same temperature (as the temperatures would similarly be equal at the start of greenhouse function), then you'll still find that the rate of energy loss to the sky exceeds the rate of energy loss via convection.  So the only reason the paper doesn't describe convection blocking as the important mechanism, and instead describes the radiative coupling to the sky as the critical mechanism, is because that's what the derived equations and the experiment show.   — Cortonin | Talk 05:31, 10 May 2005 (UTC)
replies: text: Yup, I listened to myself. And "So the only reason the paper doesn't describe convection blocking as the important mechanism, and instead describes the radiative coupling to the sky as the critical mechanism, is because that's what the derived equations and the experiment show." simply states that they don't describe or consider convection blocking - the reason the don't is that they are starting with convection blocking as a given and working from there. That warm bubble of air has to first be trapped somehow before the "derived equations and the experiment" can do anything. Gotta trap that wild warm bubble before you can analyze & experiment. Vsmith 15:52, 10 May 2005 (UTC)
replies: text: The thermodynamics of systems are described in terms of energy flow between systems.  You are saying "they don't describe or consider convection blocking ... they are starting with convection blocking as a given."  In actuality, "convection blocking" is an inverted term, as I tried to explain previously.  The correct thing to do is describe convection.  Like I said, the thermodynamics of systems are described in terms of energy flow between systems.  What is actually correct to describe is the convection between the outside environment and the upper air, because this is the active component, and this is reducing the temperature of the outside environment.  And they DO describe all the convection which does occur between the inside and the outside of the greenhouse, and include it in their model.  All convection which does occur is included.  If you want to somehow extract an inverted concept of "convection suppression", you have to calculate maximum convection and then subtract off the actual convection.  It's included, it's just that you're looking for something backwards because you're talking about what's not there, rather than what is.   — Cortonin | Talk 17:16, 10 May 2005 (UTC)

text: This little debate here is probably best exemplified by the section we had considering the gardening greenhouse versus the global greenhouse.  You keep trying to say "the temperature is all IR in the global greenhouse, but convection is suppressed in the gardening greenhouse making it hotter," and I keep trying to say, "the effects of the IR are reduced by convection in the global greenhouse, but the gardening greenhouse does not experience this as significantly because it is an isolated system."  The difference is, the first one describes what isn't, and the second one describes what is.  And the first one is wrong for doing so, because the temperature in the global greenhouse is NOT all IR.  Simple radiative flux-balancing calculations with the sun's input show otherwise.  On the large scale, the Earth is too cool for the amount of greenhouse effect it is supposed to be experiencing, because there is an active larger scale convection.  You have three systems, maybe four, with natural or artificial boundaries, the surface, the air a little higher up, the upper sky, and the inside of the greenhouse.  These surfaces are exchanging energy through various mechanisms to various degrees, and to determine their temperatures you figure out which ones exchange in which way.  So if you want to describe the effect, describe it in terms of the energy exchange which DOES actively occur.   — Cortonin | Talk 17:16, 10 May 2005 (UTC)

text: (And let me resummarize, that the "convection suppression" argument is also insufficient for the simple fact that it's not always a heating effect, as explained above.  When "the air a little higher" is warmer, convection warms and thus "suppressing" that stops this warming, making it cooler than any environment which is able to receive that warming effect.)   — Cortonin | Talk 17:16, 10 May 2005 (UTC)
thread_title:  Horticern paper 

message: Copied here from Wikipedia:Requests for arbitration/William M. Connolley and Cortonin#Temporary injunction:
Since revert wars between the Cortonin and William M. Connolley have continued through this arbitration, both users are hereby barred from reverting any article related to climate change more than once per 24 hour period. Each and every revert (partial or full) needs to be backed up on the relevant talk page with reliable sources (such as peer reviewed journals/works, where appropriate). Administrators can regard failure to abide by this ruling as a violation of the WP:3RR and act accordingly. Recent reverts by Cortonin
 
by William M. Connolley
 
 
 
Additional reverts by others involved in these revert wars may result in them joining this case. 
--mav 22:44, 23 May 2005 (UTC)
thread_title:  Temporary injunction 

message: I am making a partial revert, leaving the edits of 128.138.153.229 in place.  I'm going to keep the space in the temperature units, since that bot keeps coming along and setting them to that (which I assume conforms to the style guide).  No explanation has ever been given for the removal of the RealClimate water vapor data (in fact, it's never even been mentioned even though it has been reverted out perhaps a hundred times).  I think it's useful and provides more detail than the existing references, but it's a blog and not peer reviewed, so I will leave it out for now.  If someone else reading this finds it useful, I encourage them to add it back.  I will include it here for reference:
:RealClimate estimated that water vapor contributes between 36-66% in the cloudless case, or 66-85% if clouds are included. The lower bounds of these estimates are the amount of change if water vapor and clouds are removed, and the upper bounds are the remaining greenhouse effect if everything but water vapor and clouds are removed. 
In addition, rather than continue to revert "better known", a subjective judgment, to "other", a neutral relationship, I will simply erase that entire portion of the sentence, as it is not relevant.  I am also reincluding the the Horticern reference by Joliet et al., as it was published in a peer reviewed journal, Agricultural and Forest Meteorology, and is accessible there by electronic or physical copy for anyone with access to a good library.  The Horticern paper describes a detailed model for greenhouse function, including convection, air infiltration, and radiative exchange with the sky, and determines that for typical greenhouse configurations, the influence of radiative exchange with the sky, and its corresponding blockage by the thermal infrared barrier, is the dominant influence on the temperature of the greenhouse, and in particular, overwhelmingly dominant as the greenhouse starts out closest to the temperature of the surrounding environment, as characterized by the parameter q_sky.  In concert with that, I am reverting away the section which says that the radiative description of greenhouses is "simplistic", as this is the description present in the detailed model in the peer reviewed literature.  I am similarly reverting out the portion which says that greenhouses work by convection suppression, since this result is not found in the model in the peer reviewed literature, even though the effects of air infiltration are included in the calculation (and included in the experimental observations).   — Cortonin | Talk 03:12, 24 May 2005 (UTC)
thread_title:  Partial revert explanation 

message: (William M. Connolley 15:15, 25 May 2005 (UTC)
thread_title:  Yet more pointless words 

message: No peer reviewed source has been provided for the "[not] the same mechanism" paragraph by WMC, however, the Horticern paper does explicitely describe greenhouse function as a strong function of "sky temperature" where "sky temperature characterizes the long-wave radiation emitted by the sky", making it a physical formulation for describing the thermal infrared radiative exchange between the outside and sky and between the greenhouse and sky.  Thus, the peer reviewed material shows that greenhouses DO operate by thermal infrared absorption, not just by metaphor, but by thermal flux equation.  (It should also be noted that other literature, such as the Lindzen paper referenced, shows significant reduction of this effect in the global case due to the global-scale convection, which has been noted and described.)   — Cortonin | Talk 18:27, 28 May 2005 (UTC)
thread_title:  Partial revert explanation 

message: (William M. Connolley 20:32, 28 May 2005 (UTC)
replies: text: the Horticern paper does explicitely describe greenhouse function as a strong function of "sky temperature" where "sky temperature characterizes the long-wave radiation emitted by the sky", making it a physical formulation for describing the thermal infrared radiative exchange between the outside and sky and between the greenhouse and sky.  Thus, the peer reviewed material shows that greenhouses DO operate by thermal infrared absorption, not just by metaphor, but by thermal flux equation
See how badly C understands the physics? Of course the T in a greenhouse depends in part on downwards IR radiation. But this is not the point at issue at all. The issue is what happens to the solar energy deposited *inside* the GH, for which the sky temperature is irrelevant.
(William M. Connolley 22:20, 28 May 2005 (UTC)

text: Wood's "Communication by the author" is not a peer reviewed publication, and carries no weight compared to a modern peer reviewed experimentally confirmed model.  Calling a non peer reviewed essay from 1909 "the literature" is a severe stretch of the word, and even you know that.  As for the solar energy inside the GH, what you fail to understand, is that the solar energy deposited inside the GH is almost exactly the same as the solar energy deposited outside, so this alone has nothing at all to do with the temperature of the greenhouse, as there is a complete symmetry between inside and outside of incoming energy.  Where the two systems DO differ, is that the outside interacts not just with the sun, but more dominantly with the entire sky, while the greenhouse is largely shielded from coupling to the sky due to the glazing absorbence of that radiation wavelength.  This is the physics, I understand it, the Horticern paper describes it in great depth, and you can't dismiss it simply by saying it's "irrelevant".   — Cortonin | Talk 06:29, 29 May 2005 (UTC)
replies: text:  (William M. Connolley 10:55, 29 May 2005 (UTC)
replies: text: "though I rather suspect that Horticern may be thinking about night"??  For crying out loud, did you even read the paper?  Your comments over the past few months have strongly indicated not.  First, nearly every instance of the word "night" in the Horticern paper is in the phrase "day and night" or "daytime and nighttime", because the Horticern paper describes BOTH, as, newsflash, greenhouses exist 24 hours a day, and the physics that describes their operation is operating 24 hours a day, or else all the crops would die overnight.   — Cortonin | Talk 18:51, 29 May 2005 (UTC)

text: Second, the model you keep proposing as "remains relevant" is included in the Horticern paper as the "classical model" type which describes thermal exchange between inside and local outside environment, and it is shown to not only not yield the right predicted results (or seasonal dependence) for the constant, but to not even have the proper functional dependence under a best fit.  As I quote from the Horticern paper, "This relation is incorrect when radiative exchange to the external cladding surface is a major part of the total exchange."   — Cortonin | Talk 18:51, 29 May 2005 (UTC)

text: Reverting to match this peer reviewed literature from the modern era of science.   — Cortonin | Talk 18:51, 29 May 2005 (UTC)

text: Horticern does not "mix" them, it considers BOTH of them.  You have failed to consider night, but this is unfortunate, because nighttime offers the clearest example of how the greenhouse functions, because every variable is present which is present during the day except the sun, allowing us to only examine the other energy flows in the greenhouse.  (Since we all agree that the sun is present during the day, there is no dispute there.)  As Horticern says, "Experimental measurements over a series of nights allowed the hypothesis of a constant specific loss to be tested," which is precisely where they find out that the physical relationship you propose with all thermal exchange being convective, is not the case.   — Cortonin | Talk 19:13, 30 May 2005 (UTC)

text: It's not in the least bit out of context.  They're discussing the various models for U, and they go through various other proposed corrections, such as the inclusion of wind influence, and show why they are, and I quote, "incorrect", and then later propose a model for U which is a function of sky temperature, and includes the thermal infrared influence, and then show that this is correct.  You have either repeatedly missed this, or chose to ignore it since it did not support the port you wanted to make.   — Cortonin | Talk 19:13, 30 May 2005 (UTC)

text: And their detailed thermodynamic model explaining this and experimental confirmation of this are where?  Science doesn't work by relying on off-the-cuff comments, it works by detailed theory confirmed by experiment.   — Cortonin | Talk 19:13, 30 May 2005 (UTC)
replies: text:  (William M. Connolley 21:44, 30 May 2005 (UTC)
thread_title:  Yet more pointless words 

message: === Version 1 ===
* 1.1: The term 'greenhouse effect' originally came from the greenhouses used for gardening, but it is a misnomer since greenhouses operate differently     (Fleagle and Businger, 1980; Idso, 1982; Henderson-Sellers and McGuffie).
* 1.2: A greenhouse is built of glass; it heats up primarily because the Sun warms the ground inside it, which warms the air near the ground, and this air is prevented from rising and flowing away. The warming inside a greenhouse thus occurs by suppressing convection and turbulent mixing. 
* 1.3: This can be demonstrated by opening a small window near the roof of a greenhouse: the temperature will drop considerably. 
* 1.4: It has also been demonstrated experimentally (Wood, 1909): a "greenhouse" built of rock salt (which is transparent to IR) heats up just as one built of glass does. 
* 1.5: Greenhouses thus work primarily by preventing convection; the greenhouse effect however reduces radiation loss, not convection. 
* 1.6: It is quite common, however, to find sources (e.g.   ) that make the "greenhouse" analogy. 
* 1.7: Although the primary mechanism for warming greenhouses is the prevention of mixing with the free atmosphere, the radiative properties of the glazing can still be important to commercial growers. With the modern development of new plastic surfaces and glazings for greenhouses, this has permitted construction of greenhouses which selectively control radiation transmittance in order to better control the growing environment..
=== Version 2 ===
* 2.1: The term 'greenhouse effect' originally came from the greenhouses used for gardening. 
* 2.2: The global greenhouse effect experiences a similar thermal infrared absorption effect to what occurs with the glazing of a gardening greenhouse (Joliet, et al., 1991). 
* 2.3: The gardening greenhouse is reasonably well isolated from direct convection with the atmosphere and this isolation means that the warmed air is not free to convect out of the greenhouse. 
* 2.4: In the free atmosphere convection does play a significant role in global atmospheric heat redistribution. In the absence of atmospheric convection, average surface temperatures would be 72°C, rather than the current temperature 15°C, which is actually closer to the blackbody temperature of the Earth, -18°C, which would occur in the absence of any global greenhouse effect. 
* 2.5: This difference in temperatures is because convection facilitates redistribution of heat energy, sometimes raising hot air above much of the greenhouse gases in the same way that convection through a window of a greenhouse would move heat energy outside of the greenhouse.
* 2.6: Energy is redistributed by convection in the global greenhouse effect past the IR absorbent barrier, but very little of the energy trapped by a gardening greenhouse is able to convect past the barrier. This difference is one reason that the term greenhouse effect is sometimes called a misnomer when applied to the global system. 
=== Shuffled ===
* 1.1: The term 'greenhouse effect' originally came from the greenhouses used for gardening, but it is a misnomer since greenhouses operate differently     (Fleagle and Businger, 1980; Idso, 1982; Henderson-Sellers and McGuffie).
* 2.1: The term 'greenhouse effect' originally came from the greenhouses used for gardening. 
* 2.2: The global greenhouse effect experiences a similar thermal infrared absorption effect to what occurs with the glazing of a gardening greenhouse (Joliet, et al., 1991). 
* 1.2: A greenhouse is built of glass; it heats up primarily because the Sun warms the ground inside it, which warms the air near the ground, and this air is prevented from rising and flowing away. The warming inside a greenhouse thus occurs by suppressing convection and turbulent mixing.
* 2.3: The gardening greenhouse is reasonably well isolated from direct convection with the atmosphere and this isolation means that the warmed air is not free to convect out of the greenhouse. 
* 1.3: This can be demonstrated by opening a small window near the roof of a greenhouse: the temperature will drop considerably. 
* 1.4: It has also been demonstrated experimentally (Wood, 1909): a "greenhouse" built of rock salt (which is transparent to IR) heats up just as one built of glass does. 
* 1.5: Greenhouses thus work primarily by preventing convection; the greenhouse effect however reduces radiation loss, not convection. 
* 2.4: In the free atmosphere convection does play a significant role in global atmospheric heat redistribution. In the absence of atmospheric convection, average surface temperatures would be 72°C, rather than the current temperature 15°C, which is actually closer to the blackbody temperature of the Earth, -18°C, which would occur in the absence of any global greenhouse effect.
* 2.5: This difference in temperatures is because convection facilitates redistribution of heat energy, sometimes raising hot air above much of the greenhouse gases in the same way that convection through a window of a greenhouse would move heat energy outside of the greenhouse.  
* 1.6: It is quite common, however, to find sources (e.g.   ) that make the "greenhouse" analogy.
* 1.7a: Although the primary mechanism for warming greenhouses is the prevention of mixing with the free atmosphere, the radiative properties of the glazing can still be important to commercial growers. With the modern development of new plastic surfaces and glazings for greenhouses, this has permitted construction of greenhouses which selectively control radiation transmittance in order to better control the growing environment.. 
* 2.6: Energy is redistributed by convection in the global greenhouse effect past the IR absorbent barrier, but very little of the energy trapped by a gardening greenhouse is able to convect past the barrier. This difference is one reason that the term greenhouse effect is sometimes called a misnomer when applied to the global system. 
=== Merged ===
* 1.1: The term 'greenhouse effect' originally came from the greenhouses used for gardening, but it is a misnomer since greenhouses operate differently     (Fleagle and Businger, 1980; Idso, 1982; Henderson-Sellers and McGuffie).
* 2.2: The global greenhouse effect experiences a similar thermal infrared absorption effect to what occurs with the glazing of a gardening greenhouse (Joliet, et al., 1991).  
*: (William M. Connolley 23:05, 29 May 2005 (UTC)
replies: text: (William M. Connolley 11:15, 30 May 2005 (UTC)

text: I've seen the Takakura paper before.  It, first of all, was not peer reviewed, as it was only an abstract presented at a preceeding, which are typically not peer reviewed prior to printing (and neither are newsletters peer reviewed, which was its second appearance).  This is important, because if it had been peer reviewed, maybe someone would have noticed that he, extremely incorrectly, argues against thermal photoselectivity of films by plotting the transmittivity of films up to 1200 nm, which is a wavelength range an ORDER OF MAGNITUDE too small to represent thermal infrared transmittivity (on the order of 10,000 nm).  A peer reviewer might have caught that, I would hope, which is why we benefit from using peer reviewed material instead when it is available.   — Cortonin | Talk 18:58, 30 May 2005 (UTC)

text: In addition to this rather significant oversight which encourages him to incorrectly ignore the thermal infrared contribution, his plot in figure 1 does not show what he claims it to in the text when he writes "20 to 30% of the warming".  He examines the resultant calculated temperature at various windspeeds, and then attempts to deduce that windspeed is causing the temperature.  Consider an experiment with an oven in a wind-tunnel, where someone measures the temperature of the oven at various windspeeds, and then deduces, "Only 20-30% of the warming in the oven is due to the heat from the coils, the rest is due to there being no wind."  Would this be right?  It is a logical fallacy (argument from inverse) to draw this conclusion, and it results in many incorrect conclusions, of which this is one.  It is no different with the greenhouse, and no different in the description given in this newsletter.  I'm sorry if that violates the intuition of everyone who would like argument from inverse to be valid, but it is not.   — Cortonin | Talk 18:58, 30 May 2005 (UTC)
thread_title:  Differences and similarities 

message: * 1.1: The term 'greenhouse effect' originally came from the greenhouses used for gardening, but it is a misnomer since greenhouses operate differently     (Fleagle and Businger, 1980; Idso, 1982; Henderson-Sellers and McGuffie).
* 2.2: The global greenhouse effect experiences a similar thermal infrared absorption effect to what occurs with the glazing of a gardening greenhouse (Joliet, et al., 1991).  
*: (William M. Connolley 23:05, 29 May 2005 (UTC)
thread_title:  Merged 

message: Let's try comparing the above text. (SEWilco 21:36, 29 May 2005 (UTC)
thread_title:  Comparison 

message: Here are some online references that may help:
*How do greenhouses work? by Sue Ann Bowling, a professor of physics at the Geophysical Institute. She provide a simple, clear explanation in layman's language.
*Physics of the Greenhouse Environment, by T. Takakura et al. (originally published in the Proceedings of the American Society for Plasticulture, and later in the newsletter of the Center for Controlled Environment Agriculture. It states, in part, "The so-called 'greenhouse effect' is a very misleading term.  Although the term originated from the greenhouse itself, the higher temperature in a greenhouse is not due to the same effect which is predominant in global warming. ... Thick films seem to be effective as heat barriers, but convective heat transfer resistance of the air inside the greenhouse is a much larger factor than the resistance to heat flow through a film. ... Businger (1963), who studied the greenhouse physical environment, demonstrated the amount of warming due to the greenhouse effect by steady-state analysis. His conclusion was that this radiation absorbed by the covering accounts for only 20 to 30% of the warming in a greenhouse, and the main cause of warming is a lack of ventilation in the greenhouse.  One of the definite supporting studies is the experiment in 1900 by Wood in which he compared two model greenhouses." (The Wood paper, of course, is the one that WMC has also been citing.) --Sheldon Rampton 22:05, 29 May 2005 (UTC)
replies: text: (William M. Connolley 11:15, 30 May 2005 (UTC)

text: I've seen the Takakura paper before.  It, first of all, was not peer reviewed, as it was only an abstract presented at a preceeding, which are typically not peer reviewed prior to printing (and neither are newsletters peer reviewed, which was its second appearance).  This is important, because if it had been peer reviewed, maybe someone would have noticed that he, extremely incorrectly, argues against thermal photoselectivity of films by plotting the transmittivity of films up to 1200 nm, which is a wavelength range an ORDER OF MAGNITUDE too small to represent thermal infrared transmittivity (on the order of 10,000 nm).  A peer reviewer might have caught that, I would hope, which is why we benefit from using peer reviewed material instead when it is available.   — Cortonin | Talk 18:58, 30 May 2005 (UTC)

text: In addition to this rather significant oversight which encourages him to incorrectly ignore the thermal infrared contribution, his plot in figure 1 does not show what he claims it to in the text when he writes "20 to 30% of the warming".  He examines the resultant calculated temperature at various windspeeds, and then attempts to deduce that windspeed is causing the temperature.  Consider an experiment with an oven in a wind-tunnel, where someone measures the temperature of the oven at various windspeeds, and then deduces, "Only 20-30% of the warming in the oven is due to the heat from the coils, the rest is due to there being no wind."  Would this be right?  It is a logical fallacy (argument from inverse) to draw this conclusion, and it results in many incorrect conclusions, of which this is one.  It is no different with the greenhouse, and no different in the description given in this newsletter.  I'm sorry if that violates the intuition of everyone who would like argument from inverse to be valid, but it is not.   — Cortonin | Talk 18:58, 30 May 2005 (UTC)
thread_title:  Re: Comparison 

message: Each point raised has been responded to with explanation, and the Horticern paper remains the only peer reviewed paper presented describing a detailed experimentally-confirmed description of greenhouse operation, and it describes thermal radiative exchange as criticial to the operation of the greenhouse, with sky temperature a critical variable, so I am reverting to the version which does not rule that out, and which includes reference to the Horticern paper.   — Cortonin | Talk 19:27, 30 May 2005 (UTC)
thread_title:  Revert Explanation 

message: Newell 1970  sources it to Kondratyev 1965. Just adding it here so I can find it if needed William M. Connolley 13:21, 7 June 2007 (UTC)
thread_title:  Another ref 

message: I'd like to raise some discussion about is the real greenhouse actually working based on greenhouse effect:
Energy transmissed from ground by thermal radiation at 20 degrees Celsius:
Eb = σT4
   = 5,67·10-8W/m2K4 x (293^4)
   = 417,8818804 W/m2
Energy transmissed by thermal convection is highly dependant on temperature difference. Let's calculate what is the thermal convection when ground temperature is 25 and air temperature is 20:
a when no wind (like inside greenhouse) ~ 5 W/m^2K
E = a(T1-T2)
  = 5 *(25-20)
  = 25 W/m^2
Is the only argument on greenhouse warming up mainly by convection based on this R. W. Wood experiment from 1909?:
http://www.wmconnolley.org.uk/sci/wood_rw.1909.html  —Preceding unsigned comment added by 213.216.199.26 (talk) 21:11, 24 March 2008 (UTC)
thread_title:  Greenhouse effect in real greenhouse 

message: link to "Intergovernmental Panel on Climate Change Fourth Assessment Report. Chapter 1: Historical overview of climate change science" is:
http://ipcc-wg1.ucar.edu/wg1/Report/AR4WG1_Print_Ch01.pdf
not
http://ipcc-wg1.ucar.edu/wg1/Report/AR4WG1_Pub_Ch01.pdf
I know it's already been in debate, but since this link does not exactly state "greenhouse effect" as a misnomer, maybe wikipedia article should be somewhat more subtle? Eric DUMINIL 07:54, 30 October 2007 (UTC)
thread_title:  404 on first link 

message: Please read the new articles and consider commenting on them and/or moving some material to either one. Note that climate forcings is not specific to global climate forcings, so if it makes sense to create a separate section please do.
I hope this helps get this part of Wikipedia sorted out.
Posted to all discussion pages listed in the "See Also" section of global climate change.
--Ben 03:48, 2 Dec 2004 (UTC)
thread_title:  New Articles: [[Global climate change]] and [[Climate forcings]] 

message: yet another anon added:
: The greenhouse effect due to Carbon Dioxide is in dispute and any claims that atmospheric H<SUB>2</SUB>O contributes less than 95% to the greenhouse effect should be suspect. The actual effect of carbon dioxide is closer to 1-2% otherwise Mars' mean temperature would be substantially warmer due to having 13 times as much Carbon Dioxide by mass than Earth. Mars has an atmosphere containing over 95% CO<SUB>2</SUB> while Earth has roughly 1/30th of 1% CO<SUB>2</SUB> (ImYourDragon@aol.com)>>
This is the same old tedious nonsense so I've removed it. Notice the characteristic lack of sources; unlike the figures already in the article... William M. Connolley 22:03, 23 December 2005 (UTC)
replies: text: This is wrong on so many levels that it's hard to know where to start. The concentration of CO2 is around 385 ppm. Concentration of water vapor is highly variable -- think Sahara Desert versus the Indonesian rainforest. But in the end, that's mostly irrelevant because the radiative effects of two different gases doesn't depend on their relative concentrations: the gases absorb in different wavelength bands (with a bit of overlap, which is accounted for in all climate models). So, comparing the concentrations of H2O and CO2 is the wrong starting point. Raymond Arritt 17:53, 29 March 2007 (UTC)
replies: text: I am confused. All that is relevant are gases having a significant absorption in the region of 12 microns, corresponding roughly to the black body temperature of 288K, but10-14microns is an atmospheric window, which why it is widely used by used by thermal imagers.  The diagram of atmospheric absorption presented in the article shows that neither CO2 nor water vapour have much effect, CO2 appears to absorb in the 12-20 micron region, whilst water vapour appears to absorb both above and below this region. Since there are no scales on the vertical axis it is difficult to conclude anything from this diagram.  If these are extinction coefficients for the gases, then the diagram would indicate that water vapour would have a much greater effect than CO2, if they represent the proportion of absorption due to typical atmospheric concentrations of the two gases, then the effect of CO2 is spectacularly greater than that of water vapour.  Could somebody please clarify this.Gordon Vigurs 20:48, 7 September 2007 (UTC)
thread_title:  Yet more tedious septic nonsense 

message: My understanding has been that if a car's windows are left closed on a hot sunny summer day and the interior of the car heats up, or if the interior of an actual greenhouse warms up in the same way, those are instances of the greenhouse effect (and indeed, the latter example is why it's called the greenhouse effect).  But the first paragraph of this article seems to say it's the greenhouse effect only if it's applied to the planet as a whole. Michael Hardy 01:43, 4 March 2006 (UTC)
replies: text: See the section Real greenhouses at the end of the article. Also if you like old controversy check out the edit wars of last spring - it was a bit tedious. :-) Vsmith 03:29, 4 March 2006 (UTC)
thread_title:  too narrow a definition? 

message: Removed :Image:Spectrum of blue sky.gif as it was redundant with image already in the article. Initially mis-read the caption. Vsmith 13:17, 13 May 2006 (UTC)
thread_title:  Image:Spectrum of blue sky.gif 

message: website at bottom is incorrect
:what cryptic message is this, come upon us as from the oracle, to vex our minds with contrary incomprehensions? Gzuckier 19:48, 31 May 2006 (UTC)
thread_title:  links 

message: I just read the introduction, and I think there is a style change that spoils the flow of the article. The first few sentences come across as you would expect for an encyclopedic article on a scientific subject, being dispassionate and stating or explaining facts. The change comes with: "No-one disputes the former, or its magnitude; the latter is accepted by a large majority of scientists, although there is some dispute as to its magnitude (see scientific opinion on climate change and attribution of recent climate change)." - this sounds like what it is, an attempt to forestall editors who might want to tweak the wording of this article, or turn it into a diatribe on global warming. This was probably done with the best of intentions, but as it stands, the wording sticks out like a sore thumb and significantly detracts from the value of the article. I would like to try and improve that part of the introduction, but wanted to find out if anyone agrees with me about the need to rewrite that sentence. So, does anyone think that sentence needs rewriting? Carcharoth 21:21, 23 June 2006 (UTC)
replies: text: I strongly disagree that the wording detracts from the article. If you want to try to improve it, feel free, but bear in mind this is a controversial topic and that wording has survived for a fair while. I don't see any need to improve it William M. Connolley 21:30, 24 June 2006 (UTC)
thread_title:  Style change in introduction feels confrontational