Klimaforskning - hjemmeside
Startet av Jostemikk, februar 22, 2012, 18:06:08 PM
SitatClimate Realist says: February 22, 2012 at 7:07 AMRoy,Your example of the IR thermometer is bogus. As Claes said, heat can NEVER pass from a cold ojbect to a warmer object. The IR thermometer is detecting IR, yes, but could not do so if it were unpowered. The detector requires a work input, i.e. a voltage to be able to detect IR. The thermometer itself is detecting IR which is as a result of temperature, it is not detecting the colder temperature by absorbing heat from a colder object.
SitatA better test would be to use a mercury thermometer that works by directly absorbing kinetic heat and not by IR. So, take a mercury thermometer at room temperature and place it in either the fridge or the freezer and the temperature will drop. The colder fridge or freezer will NEVER warm the mercury thermometer that is at 20C, they will always cool it.
SitatClaes Johnson says: February 19, 2012 at 10:30 AMHi Roy: You seem to believe that the emission of heat energy from a hot body (plate) is independent of the temperature of the surrounding medium (the other plate). What is your scientific evidence that this is the case? In particular you seem to indicate that even in an environment of the same temperature, a body would continue to emit heat energy. AgainAt the same time you seem to indicate that one can as well forget about backradiation with its confusing "back" and simply talk about net flow of heat energy from hot to cold depending on the temperatures involved. Why can't you then do this, and simply stop to speak about backradiation? Or do you have some hidden motivation to speak about it?Best regards.Claes
SitatRoy W. Spencer, Ph. D. says: February 19, 2012 at 11:33 AMYes, Claes you found me out. I have nefarious motives for using certain terminology. It's simply to annoy you. Roy W. Spencer, Ph. D. says: February 19, 2012 at 5:12 PMOK, since you want a serious answer, Claes...The evidence you seek is beautifully produced by a handheld infrared thermometer. If the IR thermometer is at room temperature, and you point it at the inside of a refrigerator, it reads a cold temperature. Why? Because the refrigerator-viewing side of a thermopile inside the IR thermometer cools in response to the extra loss of IR energy toward the cold target. Circuitry inside the IR thermometer estimates the temperature of the viewed target based upon the rate of temperature drop of one side of the thermopile.If you point the thermometer at a hot target, the opposite happens.Regarding 'back' radiation, "a rose by any other name is still a rose". The downwelling IR radiation emitted by the sky toward the ground still exists no matter what you call it.
SitatClaes Johnson says: February 20, 2012 at 7:04 AMHere you state that the "back" is superfluous, yet you don't want to give up your cherished idea of "back" radiation. Don't you see that this is contradictory? You act just like Judy, first defending backradiation as a physical phenomenon, then taking a step back and saying that after all there is no "back", that it is just a way of speaking without physics since after all only the net counts. Like Judy you have thereby backed off from backradiation and I guess you will see no meaning in continuing to send out disinformation about the non-physical phenomenon of backradiation or "downwelling radiation" which is the same. Right?
SitatClaes Johnson says: February 19, 2012 at 1:22 PMRoy:Since you don't answer my serious question in a serious way I repeat it in a blog post:http://claesjohnson.blogspot.com/2012/02/why-is-roy-spencer-not-serious.htmland ask you to answer in a comment to the post.Seriously,Claes
SitatRoy W. Spencer, Ph. D. says: February 21, 2012 at 8:13 AM...The IR thermometer is indeed DIRECT evidence that variations in the effective emitting temperature of the sky, which is strongly modulated by greenhouse gases (mostly water vapor) DOES affect surface temperature...in this case, the surface temperature of the thermopile which is pointed at the sky.How else can you explain such evidence, Claes? I really cannot tell whether you are serious, because the evidence is so clear. While I am tempted to flag your comment as intellectually dishonest, I will give you the benefit of the doubt and assume you are just misinformed.
SitatClaes Johnson says:February 21, 2012 at 8:36 AMRoy, suggesting dishonesty is not very nice. I have written about IR-sensors on http://claesjohnson.blogspot.com/search/label/IR%20cameraThe evidence is clear: There is never any direct recording of backradiation. Your IR sensor measures the temperature of the target, or frequency of radiation from target, but never NEVER does it measure any flow of heat energy from a colder target to a warmer receptor, because there is nothing to measure. IT DOES NOT EXIST...
SitatRoy W. Spencer, Ph. D. says: February 21, 2012 at 10:46 AMOK, let me see if I understand you, then. You are claiming that a body emits IR radiation at sigma*T^4 only if it's surroundings are at zero Kelvin. The rate of emission would then be reduced the warmer the surroundings.If this is your position (even if this isn't your position), then answer this question: Does the atmosphere reduce the intensity of IR radiation flowing from the Earth's surface to space, compared to if there was no atmosphere?
SitatClaes Johnson says: February 21, 2012 at 11:45 AMYes Roy, it does, but not because of any backradiation. An Earth with fully transparent atmosphere would most likely be cooler than the one we have, but it is not so clear how much cooler, probably something between 15 and 30 C cooler.The concept of backradiation is misleading and dangerous because it is non-physical: THERE IS NO FLOW OF HEAT ENERGY FROM COLD TO WARM.
SitatRoy W. Spencer, Ph. D. says: February 22, 2012 at 8:41 AMReposting this response to Claes:Sorry, I've been attending to my job and family.It seems your objection is to the existence of any IR radiation flowing from cooler bodies to warmer bodies as part of the radiative transfer process. Without studying the issue more, I cannot think of an immediately obvious way to prove you are wrong.But the net effect on radiative transfer might be the same whether you use the concept of back radiation or not...in the usual calculation of radiative flux divergence of radiation in an atmospheric layer, there are radiative fluxes being absorbed by the layer from layers on either side, and there is flux being emitted by the layer. The sum of these is the *net* flux divergence, which you claim is in reality the only flux which is occurring. This is my understanding of your position.If you want to think of it that way, then I cannot immediately think of an example which proves you are wrong. But all we are discussing here are the details of the mechanism by which IR energy flows from a warmer body to a cooler body. It does not change the fact that making the cooler body a little warmer will then reduce the rate of IR emission from the warmer body to the cooler body, which through conservation of energy means it will change the temperature of the warmer body. One does not necessarily need to invoke "back radiation" to achieve that effect.Since you admit that the presence of an atmosphere reduces the rate of IR emission from the surface to outer space, then you implicitly admit that something like the "greenhouse effect" does exist, at least in terms of its influence on surface temperature. You are just disputing the details of the mechanism usually used to explain the process. Am I correct?
SitatClaes Johnson says: February 22, 2012 at 11:47 AMAgain: there are no IR-photons busy carrying heat energy back and forth between two bodies of equal or different temperature. Two radiating bodies communicate by electromagnetics waves which allow heat transfer from warm to cold, but not the other way because that would be an unstable process violating the 2nd law. Einstein understood very well that IR photons represent pseudo-science but few physicists are willing to listen to Einsteinn, unless it is something about curved space-time which nobody understands anything about.Roy W. Spencer, Ph. D. says: February 22, 2012 at 12:16 PMOK, then if the IR photonic detector measures one intensity of "EM waves" from an object colder than itself, and a different intensity from the object when at a different temperature, would that be evidence that colder objects emit IR radiation toward warmer objects? If not, why not?Claes Johnson says: February 22, 2012 at 12:49 PMRoy: two radiating bodies communicate or stay in contact through electromagnetic waves, like two people speaking on the phone. But it is always the wiser/warmer who transfers knowledge/heat to the colder/dumber, never the other way around. Is this so very difficult to understand?. The term radiation is used with two meanings, as means of communication and as transfer of heat energy, and makes the discussion so difficult. Once this is understood the situation becomes clear, right? Roy W. Spencer, Ph. D. says: February 22, 2012 at 12:18 PMI largely agree with Steve's description of what happens as what I *believe* happens, but I still cannot yet disprove Claes' alternative explanation.
SitatI have made the following comment on Roy Spencer's web site, concerning his defense of the greenhouse effect.Roy Spencer wrote: "...the cooler object (the atmosphere) keeps the warmer object (the ground) warmer than if the atmosphere was not there. That's the (so-called) greenhouse effect."Two points of simple fact, no three:1) That is NOT the greenhouse effect that the IPCC and all of our suborned institutions are foisting upon the public. The greenhouse effect is an increase in atmospheric temperature with increasing atmospheric carbon dioxide. You are dissembling (intentionally or not) in refusing to admit that, and adhere to it. (And so is "steveta_uk", who commented above, "The absurd idea that GHE results in INCREASING surface temperatures is simply a misreading of the theory." That statement itself, in the face of the public debate over "global warming", is the height of absurdity, and in a sane intellectual atmosphere, could rightly be called a bald-faced lie. However, I understand that it is just the madness of those whose religiously-held belief in the greenhouse effect--and in the inerrancy of an overwhelming, albeit incompetent, consensus--is being strongly challenged by skeptics.)2)I have DISPROVED the greenhouse effect, in my comparison of the temperatures in the atmospheres of Venus and Earth. YOU ARE INCOMPETENT as a physical scientist if you cannot see that simple fact.3)You delude yourself by thinking the atmosphere keeps the surface warmer due to "backradiation", a.k.a. "downwelling longwave radiation". Since there is no greenhouse effect, I think it should be obvious that the atmosphere at night is keeping the surface from cooling faster, because upward heat transfer is not by radiation alone, with an atmosphere present, but also by convection and conduction, and these are SLOWER THAN RADIATION, and I would think can even reverse direction, against the temperature gradient, and even reverse it locally (downdrafts, precipitation, temperature inversions). That's what the radiative transfer theory does to you: It makes you forget there ARE even convection and conduction. Your miseducation makes you part of the problem, Dr.--and of course you are not alone, climate scientists have been miseducated for, what, forty five years (I have read that 1967 or 1968 is when the current radiative transfer theory, applied to atmospheric warming, was brought out and accepted), and there has not been a competent climate scientist for at least the last 20 years, since the detailed temperature and pressure data of Venus, which should have signaled the death of the greenhouse effect as accepted science, was obtained by the Magellan spacecraft. Of course, the bottom line is, the very idea of "runaway climate", and thus of looking at climate as something balanced on the knife edge of "radiative forcings", only came into science through a mass turning away from, or forgetting of, the stability of the Standard Atmosphere (which of course my Venus/Earth comparison confirmed). Climate scientists' faith in radiative transfer theory is blind to the definitive facts, and has caused the failure--FAILURE, SIR--of their science. I am ashamed of all of you, and of what you continue to do, unseeing and undeterred by the strongest admonitions, to the integrity and natural authority of science.
SitatHarry Dale HuffmanFeb 21, 2012 01:06 PMI have commented on Spencer's site, and posted on my own blog:Incompetent Skeptics III: Roy SpencerI am disgusted with all climate scientists, who have caused the failure of their science.
SitatAsk why is it so? says: February 22, 2012 at 7:31 AMRadiation (i.e.Short Wave and Long Wave)is not heat. Radiation is energy i.e. photons that can only travel in straight lines from the source or reflection and temperature does not determine its direction. Heat on the other hand can travel in any direction as long as it is in accordance with the 2nd Law of Thermodynamics which BTW means heat from the source through expansion always radiates outwards which is to a cooler place. The two are very different forms of energy. The question is not whether back radiation exists because I believe it does, the question is can this back radiation have a positive net effect on the daily maximum temperature of the planet?The temperature of the planet is determined by Total Solar Radiation and in accordance with the Laws of Thermodynamics once the energy is converted there is always an amount of energy that is unusable i.e. entropy. With each conversion there is always a loss of usable energy. Back radiation is the result of conversion and therefore contains less energy than the initial conversion. In other words the hotter object i.e. TSR will over-ride the cooler object i.e. re-emission and the effect of this on the maximum temperature achieved by the earth per day/day light hours will be 0. Two heat sources in a room at 0 degrees, one warms the room to 30 degrees and the other to 10 degrees, what will be the temperature of the room? Even though there are two heat sources the temperature will not exceed 30 degrees.If I turn off the 10 degrees heat source the room will still warm to 30 degrees.It is the speed at which the room warms that alters not the maximum temperature.