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Discussion > Simon Abingdon/Jonathan Jones/Radiative transfer

Can we have a "RKS v Richard Drake: Slapdown" thread somewhere?

No need to be so grumpy everyone. I'd love mdgnn to be right, which is why I'm being extra extra careful with it. I'd love UFOs to be real too, which is why I'm extra skeptical about them too - easy to fool yourself when you want it to be true.

May 3, 2012 at 4:10 PM | TheBigYinJames>>>>

Point well made and taken on board.

Fingers crossed we can continue discussing the physics in the same way as we are on unthreaded.

May 3, 2012 at 4:22 PM | Unregistered CommenterRKS

James, I've been insulted and defamed by someone using a pseudonym. But he's also claimed that mdog has been shown respect by people who "really do know their science" in "in depth scientific discussions". I'd like that piece to be noted and retained. Because I'd genuinely like to know exactly which discussions RKS refers to - and which people he thinks really know their science and indeed what they said to and about mdog specifically.

Meanwhile I strongly agree with your caution about a theory which 'ticks all the right boxes' in seeming to lead to an immediate casting of CAGW into the dustbin of history. Steve McIntyre has made this point many times, for example on Svensmark here:

Please do not get all excited about cosmic stuff. Please do not accept something simply because you like the answer. Apply the same rigor as you’d expect from bristlecones.

That was written just after Climategate, in December 2009. There was plenty of masonry falling in the CAGW house at that point which is why I appreciated Steve's warning so much. And Svensmark is a known scientist with a long record of publication. Indeed the CLOUD experiment at CERN has been encouraging for him since.

With something by comparison so early-stage, from someone determined to be unknown and highly unreliable in dealing with criticism, we should be many times more circumspect.

May 3, 2012 at 4:33 PM | Unregistered CommenterRichard Drake

This is a good reason for pseudonyms if ever there was one - if you were DickyDuck instead of Richard Drake, not only would you not be defamed, you wouldn't FEEL defamed either.

I am often amused when I see mydog pop up at Delingpole under a different pseudonym, it's definitely he, though.

May 3, 2012 at 5:24 PM | Unregistered CommenterTheBigYinJames

I personally don't feel all that defamed James but I have known cases where people's lives were ruined. So it's the principle that matters. And that includes whether we want people increasingly to back out of using real names on climate blogs. Surely not. And I never will, just for the record.

But I emphasize again my focus now is on RKS telling us which threads of "in depth scientific discussions" have had people who "really do know their science" showing respect to mdog. It's a genuine question. Let's have mdog's five greatest hits, so to speak, as far as persuading or at least challenging those who know their science. There'd surely be plenty to learn from such a list and I'm genuinely keen to learn. If on the other hand RKS doesn't provide any details at all (including which people he thinks really know their science) then I think this paragraph

I think you are just hiding behind a pseudonym, because I've never heard reference to your name on blogs covering in depth scientific discussion, and where mydog gets a respectful hearing from contributors who really do know their science.

is just a nasty way of saying I'm ignorant, with only impressive-sounding handwaving in the background. How can any one person know where the most important in depth scientific discussions are going on in the vastness of the blogosphere? Science of Doom? Climate Etc? I may have missed something important so it's a genuine question. Even if RKS is determined not to apologise for anything he's said about me I think he's required to address this and it's surely bang on topic for this thread.

May 3, 2012 at 5:46 PM | Unregistered CommenterRichard Drake

:-)

May 3, 2012 at 9:45 PM | Unregistered CommenterBBD

?

May 4, 2012 at 6:55 AM | Unregistered CommenterRichard Drake

At the risk of being told to f.. off. I have a question for the good professor.

I am sitting in front of a radiant heater some feet away. Getting pleasantly warm. My body temperature is about 37 degree C. The temperature of the radiant heater is about 1000 degree C. According to Mr. Steffan and Mr. Boltzman I am radiating at some wavelength in some way commeasuret with my body temperature. Am I warming the heater, and if yes, how am I doing this?

May 5, 2012 at 10:31 PM | Unregistered CommenterGeorge Steiner

At the risk of being told to f.. off. I have a question for the good professor.

I am sitting in front of a radiant heater some feet away. Getting pleasantly warm. My body temperature is about 37 degree C. The temperature of the radiant heater is about 1000 degree C. According to Mr. Steffan and Mr. Boltzman I am radiating at some wavelength in some way commeasuret with my body temperature. Am I warming the heater, and if yes, how am I doing this?

May 5, 2012 at 10:31 PM | George Steiner>>>>

I'm still waiting to hear what percentage of surface radiation would be 'back radiated' by 0.039% of the atmosphere [bit of a big gap between molecules] assuming that instead of an emissivity of around 0.01 [an unrealistic maximum] that the emissivity of this gas was actually ONE. - And also assuming [again unrealistically] that ALL emitted radiation was back to the surface [ignoring emissions between CO2 molecules in all directions and thence to other gaseous molecules throughout the lower and upper troposphere].

And, as a related question, what happens to this radiation AFTER that when we're told that for system Earth - Energy in = energy out?

Once we can agree on that we can work backwards to calculate the effects at more realistically.

There were lots of rude comments attempting to sidetrack the question, on a thread supposedly .

And, as a related question, what happens to this radiation AFTER that when we're told that for system Earth - Energy in = energy out?

Once we can agree on that we can work backwards to calculate the effects at more realistically.

There were lots of rude comments attempting to sidetrack the question, on a thread supposedly discussing the hypothetical effects of back radiation, but no sensible response.

At no time have I questioned the existence of back radiation on this thread, I just want to achieve a realistic quantitative value of it's effect on Earth's climate. - Not from proxies or statistical atmospheric measurements, but by proper analysis of the physical properties of CO2.

Where's the problem?

May 6, 2012 at 4:22 PM | Unregistered CommenterRKS

According to Mr. Steffan and Mr. Boltzman I am radiating at some wavelength in some way commeasuret with my body temperature. Am I warming the heater, and if yes, how am I doing this?

May 5, 2012 at 10:31 PM | George Steiner>>>>>

After well over a century of thermodynamics research the answer is "We'll get back to you after we figure it out".

May 6, 2012 at 4:58 PM | Unregistered CommenterRKS

May 5, 2012 at 10:31 PM | Unregistered CommenterGeorge Steiner

At the risk of being told to f.. off. I have a question for the good professor.

I am sitting in front of a radiant heater some feet away. Getting pleasantly warm. My body temperature is about 37 degree C. The temperature of the radiant heater is about 1000 degree C. According to Mr. Steffan and Mr. Boltzman I am radiating at some wavelength in some way commeasuret with my body temperature. Am I warming the heater, and if yes, how am I doing this?

Well, I'm not the professor, but I'll take it upon myself to reply.

According to my understanding of the physics of thermal radiation as expressed in standard texts on radiative heat transfer:
1. Yes
2. You are doing it by radiating photons. Each photon carries carry no record of your temperature, even though someone intercepting sufficient of them could deduce your temperature by plotting a histogram of their energies. Depending on its reflectivity, the radiator will absorb some photons coming from you, even though their average wavelength is much greater (end their average energy much less) than the photons being emitted by the radiator. Each photon from you absorbed by the radiator will warm it as it carries a small but finite energy.

The fact you have posed your question at all suggests that you may not agree with this answer.

May 6, 2012 at 10:39 PM | Registered CommenterMartin A

According to my understanding of the physics of thermal radiation as expressed in standard texts on radiative heat transfer:
1. Yes
2. You are doing it by radiating photons. Each photon carries carry no record of your temperature, even though someone intercepting sufficient of them could deduce your temperature by plotting a histogram of their energies. Depending on its reflectivity, the radiator will absorb some photons coming from you, even though their average wavelength is much greater (end their average energy much less) than the photons being emitted by the radiator. Each photon from you absorbed by the radiator will warm it as it carries a small but finite energy.

The fact you have posed your question at all suggests that you may not agree with this answer.

May 6, 2012 at 10:39 PM | Martin A>>>>>>

Hi Martin.

That's a perfectly reasonable personal interpretation of the standard texts.

As with all standard science taught to us, are there any practical experiments in the texts to demonstrate exactly this result along with quantitative results, because I've not been able to locate any and it would help my overall understanding of this property of radiative physics if these results were publicly available.

I'm not being combative, but being an engineer I like to see sound results of reproducible experiments in order to make use of the properties available to me.

May 7, 2012 at 2:02 AM | Unregistered CommenterRKS

May 7, 2012 at 2:02 AM RKS

"...are there any practical experiments in the texts to demonstrate exactly this result along with quantitative results"

Hi RKS,

Not that I know of. But I'd find it hard to point to practical experiments that confirm precisely any of the natural laws (Newton's laws of motion for example) that we use every day. Other than the undoubted fact that satellites orbit as expected, cathode ray tubes display as expected, nuclear reactors produce heat as expected and so on.

Radiative laws were discussed on Scienceofdoom some time back in reponse to the sizable minority who think that they are incompatible with the laws of thermodynamics. I'll try posting a query to ask what experimental work was done to confirm the radiation laws.

May 7, 2012 at 7:44 AM | Registered CommenterMartin A

Radiative laws were discussed on Scienceofdoom some time back in reponse to the sizable minority who think that they are incompatible with the laws of thermodynamics. I'll try posting a query to ask what experimental work was done to confirm the radiation laws.

May 7, 2012 at 7:44 AM | Martin A>>>>>

Thanks for the response.

Not too sure about the objectivity of Scienceofdoom though, WUWT regard them as a pro AGW site.

Still, if they can point to some reproducible results it should be ok.

May 7, 2012 at 10:11 AM | Unregistered CommenterRKS

I think Martin A gives something more than a "personal interpretation" of standard texts. Black body radiation (and remember that a Black Body is a perfect absorber as well as emitter of radiant heat) according to the Stefan-Boltzmann law has been experimentally tested many times.

Boltzmann's theoretical basis is strictly based on statistical thermodynamcs - and thus rescued Planck from the Ultraviolet Catastrophe.

I haven't read this whole thread (and I suspect it would be unprofitable) but I notice RKS "as an engineer" doubts the principle. What have I missed?

May 7, 2012 at 1:41 PM | Unregistered Commenterlogicophilosophicus

I haven't read this whole thread (and I suspect it would be unprofitable) but I notice RKS "as an engineer" doubts the principle. What have I missed?

May 7, 2012 at 1:41 PM | logicophilosophicus>>>>>

Strange you note I am an engineer but fail to note that on a slightly earlier post I stated I had not questioned the existence of back radiation [the subject of the thread - which you seem to feel might be "unprofitable" for you].

The discussion is not simply about radiation from a black body. It is about the interaction between two bodies due to back radiation from one of them.

If you can point us to quantitative results from an experiment dealing with this condition I'm sure we'd be extremely grateful to you, because we're having trouble finding finding the info we need.

I'm not sure what your odd comment about engineers was about, but without them to put research to practical use much scientific work would not receive funding. Give us the well researched empirical results and we'll build the kit for you. Vague ideas are for academic discussion.

As you seem to be familiar with the subject, I'd appreciate it if you'd care to give some input to my question of May 6, 2012 at 4:22 PM on this thread.

May 7, 2012 at 2:15 PM | Unregistered CommenterRKS

I was surprised that an engineer had suggested that "over a century of thermodynamics research" had failed to show how a cooler body contributes some radiant heat to a hotter one. I'm not a scientist of any kind, but I would class scepticism about the major physical theories - Newton's Laws of Motion, the conservation of mass-energy, the Laws of Thermodynamics, etc - as Flat Earth territory.

WRT your May 6th 4.22 pm post, I'm no expert, and you cover a lot of ground. Looking at your first paragraph, though, I think you fail to realise that CO2 is opaque to certain wavelengths in the infrared to which N2 and O2 are transparent. (H2O is the major greenhouse gas, but its absorption/radiation bands are basically at different wavelengths from CO2.) The atmosphere is transparent to visible light, which is largely absorbed by ocean, land and vegetation and reradiated as IR. Virtually all the radiation in the CO2 absorption band is absorbed in the lower atmosphere. Most is reradiated away from the earth, of course, let's say x%. It is immediately reabsorbed and reemitted, so now (crudely) x% of x% is heading skywards. That happens many, many times, and x/100 raised to a high power is miniscule.

You mention "other gaseous molecules" which absorb radiation in the CO2 band - that too, I think, is an error, apart from partial overlap of absorbed/radiated wavelengths for H2O.

What CO2 does is well known, and demonstrable ever since Tyndall, 150 years ago. The big issue is what H2O does, in its various forms, and that is where the uncertainty lies. But, as I said, this s just secondhand knowledge to me - I'm no expert.

May 7, 2012 at 3:10 PM | Unregistered Commenterlogicophilosophicus

I was surprised that an engineer had suggested that "over a century of thermodynamics research" had failed to show how a cooler body contributes some radiant heat to a hotter one. I'm not a scientist of any kind, but I would class scepticism about the major physical theories - Newton's Laws of Motion, the conservation of mass-energy, the Laws of Thermodynamics, etc - as Flat Earth territory.....May 7, 2012 at 3:10 PM | logicophilosophicus>>>>

Excellent - point us toe the results of experiments so we can see some actual quantities rather then talking around the houses.

CO2 is not opaque at any wavelength but has definite values of emissivity - perhaps you might state what value of emissivity might be classed as opaque.

I notice your explanation of the process does not mention back radiation so are you saying that CO2 is behaving as a blanket?

And we're still asking for values to give to the two body hypothesis which is the subject of the thread.

A few x's here and there are just mind games. When an engineer makes use of physics there can be no cause for error, all physical properties must be fully quantified in order to be used as a tool - They deal with the real world and leave mind games to the academics.

May 7, 2012 at 3:42 PM | Unregistered CommenterRKS

The penny has dropped. You are clearly a follower of (or contributor to?) "Biology Cabinet". Nasif Nahle's pseudoscience has been amply criticised elsewhere - just search the web. Those x's you dismiss are the reason your (i.e. Nasif Nahle's) hemispherical argument is irrelevant. They are also why partial transmission eventually boils down to effective opacity. Of course, eventually that energy escapes, though your "what happens next" question suggests that you haven't grasped this: a rise in temperature (e.g. the CO2 warming effect) does not contradict the inevitable new equilibrium of energy in = energy out.

Those little x's, or the approximation "opaque", are exactly the kind of back-of-an-envelope arguments I usually get from engineers. Challenging standard physical theory on the basis of fringe theorists of dubious credentials is more characteristic of flat earthers and - more worryingly - gives CAGW sceptics a bad name.

May 7, 2012 at 4:38 PM | Unregistered Commenterlogicophilosophicus

Martin A - when I was at school, studying elementary physics, we had to conduct an experiment involving rolling a vehicle attached to a ticker-tape down an inclined plane in order to get experimental confirmation of Newton's Laws of Motion. Needless to say, friction and experimental haphazardness rarely permitted us to get very close to the right answer but we could get to the ballpark. And of course there are numerous examples of observations in nature that confirm, or show the need for adjustment to, Newton's "laws".

I, amd other people on this thread, have been wondering whether there are any lab write-ups of ,say Angstrom's confirmation of Arrhenius, this black-body question, etc etc.

I do not take the lack of immediately available experimental confirmation to be evidence of absence of experimental confirmation, but it would be interesting to see what empirical proof there is.

May 7, 2012 at 4:53 PM | Unregistered Commenterdiogenes

Those little x's, or the approximation "opaque", are exactly the kind of back-of-an-envelope arguments I usually get from engineers. Challenging standard physical theory on the basis of fringe theorists of dubious credentials is more characteristic of flat earthers and - more worryingly - gives CAGW sceptics a bad name.

May 7, 2012 at 4:38 PM | logicophilosophicus>>>

What on earth are you mumbling on about? Biology cabinet? Nasif Nahle? - Let's get back to some science instead on your nonsensical politics.

May 7, 2012 at 5:55 PM | Unregistered CommenterRKS

I do not take the lack of immediately available experimental confirmation to be evidence of absence of experimental confirmation, but it would be interesting to see what empirical proof there is.

May 7, 2012 at 4:53 PM | diogenes>>>>

Hi,

Exactly what I've been saying quite politely but it seems any discussion of back radiation seems to pick up more than it's fair share of nut-cases who won't have it's effect on climate questioned.

Radiation goes in all direction so back radiation towards a stimulus is obvious. On this thread we're looking to quantify the interaction between source and 'back radiator'. The effect of back radiation on temperature of the climate is virtually zero, and I still look forward to empirical data, not atmospheric statistics, disproving that.

There are other far more likely drivers of climate which don't rely on fancy accounting to calculate their effects but that's for another thread.

May 7, 2012 at 6:11 PM | Unregistered CommenterRKS

"The carbon-dioxide trap is very strongly absorptive over a wavelength range from 14 micrometres to 16.5 micrometres... scarcely any [such] radiant heat generated at ground level succeeds in penetrating the trap. There is essentially no escape through the trap into the higher atmosphere and thence into space. Blocked radiation is either re-emitted (after being absorbed in the trap) downward to the ground immediately, or absorbed again by the gas generating the trap, in which case there is a further re-emission. Sooner or later, perhaps after many absorptions and re-emissions, the trapped radiation reaches the ground... the carbon dioxide blocking about 15% of the heat energy and water vapour the remaining 27% [of the heat radiation from the Earth's solid and liquid surfaces]... The surface of the Earth cannot cool itself as efficiently as the imaginary body [grey sphere] would be able to do." (Sir Fred Hoyle, 1981. I picked Hoyle not just for his clarity but also because this is definitely pre-AGW-scare thinking, and because Hoyle was, in those latter days, a CAGW sceptic.)

So within that waveband atmospheric CO2 is effectively opaque, and effectively all radiation in that band is radiated back to the surface. That's what I'm mumbling about. What are you mumbling about? What do you mean by "the" emissivity of CO2, and why is it relevant? Why would anyone try to model the described process of multiple absorption and re-emission as the one-off effect of a solid hemispherical black body emitter?

The "Biology Cabinet" reference you did not recognise was triggered by your use of the silly hemispherical argument, the fixation on an imaginary CO2 body with emissivity = 1, and a couple of other little simlarities. I guess they must have been absorbed and re-emitted from one dodgy source to another. What kind of engineer are you anyway? You ask "...what happens to this radiation AFTER that when we're told that for system Earth - Energy in = energy out?" Clearly you assume that in ANY state of equilibrium for the Earth the heat content must be the same. Everybody I know thinks that a global 1K temperature rise locks up thousands of trillions of trillions of Joules in the hydrosphere especially, much of that as phase changes (which, by the way, means that Work is done, which seems to be denied by several in this thread). Also you insist that back radiation has not been measured experimentally. Here's a really obvious sceptic source:

http://www.drroyspencer.com/2010/08/help-back-radiation-has-invaded-my-backyard/

Then there's the Met Office TAFTS programme, or the well known comparison between satellite measured emission spectra and ground-based emission spectra for the atmosphere.

Enough.

May 7, 2012 at 9:52 PM | Unregistered Commenterlogicophilosophicus

OK, I've posted qthe following on ScienceofDoom:
Could you help me come up with an answer as to where one can find description of physical measurements that confitm these relations? Or maybe they follow inevitably as the consequence of simpler more fundamental laws that have been confirmed by physical measurements?

Let's see what help they can give us.

Not too sure about the objectivity of Scienceofdoom though, WUWT regard them as a pro AGW site.

Still, if they can point to some reproducible results it should be ok.

I have no reason top doubt ScienceofDoom's understanding of physics which is always expressed very clearly and, in areas where I am qualified to judge, correctly. Plus, their attitude is helpful and welcoming, in contrast to some other sites.

They don't entertain postings that question established physics, telling posters of such things to discuss those matters elsewhere.

May 7, 2012 at 10:08 PM | Registered CommenterMartin A

May 7, 2012 at 9:52 PM logicophilosophicus

"Enough"

Sure is!

Just love all those "thousands of trillions of trillions of Joules"! Though somehow I am not surprised that :-

"Everybody I know thinks that a global 1K temperature rise locks...” Somehow it is not surprising that everybody you know thinks the same as you.

Ah, "phase changes" many. many, moons ago solidification models of alloys, finite element heat transfer models! Magic times we had fun! Went to the pub to play snooker whilst a 386 crunched a little simulation. Then we took months and years to verify the models by observing and measuring the actual alloys solidifying. A very warm and rewarding process, accumulating actual empirical data still holds true today.

Have a mega day! Watch out for all those "thousands of trillions of trillions of Joules" You never know they might all eventually become yours!

May 7, 2012 at 11:59 PM | Registered CommenterGreen Sand

Green Sand.

Not surprising that they think that way because that's how it is. Water has a Specific Heat of something like 4 kJ per litre per degree Celsius, I think, and there are - again from memory - more than 10^20 litres of water in the sea. The new equilibrium, given a final temperature increase of 1K, would therefore lock in more than 10^23 Joules of energy. If the people you know don't think that's so, feel free to pass on the message.

May 8, 2012 at 12:46 AM | Unregistered Commenterlogicophilosophicus