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Comments 90351 to 90400:

90351. grayman at 09:29 AM on 31 March 2011
       Was Greenland really green in the past?
       Rob I will check it out and get back to you.
       Moderator Response: [muoncounter] Have a look at CCNY's cryocity.org Greenland 2010 report as well.
90352. ranyl at 09:28 AM on 31 March 2011
       Arctic Ice March 2011
       "I suggest that by mid-April the sea ice will be in a similar condition to that of late August 2010. In plain terms, the 2011 melt season will soon continue more or less where the 2010 melt season left off." Does this mean that the in April 2011 the volume of sea ice will be the same as in late Aug. 2010? Because I can't see how it means that the arctic melt is a month ahead as suggested by D. Bailey, however for "By April 30th, ice extent graphs will show a strong downward trend similar to that of May - June 2010." that seems to be the case. Lawrence, D.M., A.G. Slater, R.A. Tomas, M.M. Holland, and C. Deser, 2008: Accelerated Arctic land warming and permafrost degradation during rapid sea ice loss. Geophys. Res. Lett., 35, L11506, doi:10.1029/2008GL033985. This article is suggestive that losing the summer sea ice will accelerate arctic region, extending 1000 mile south, by 3.5X, and that model didn't include the more recent data on the increased stength of the albedo effect reported by Flanner et al, Nat. Geo, vol 4, 151-155, 16 Jan 2011, "we conclude that the albedo feedback from the northern Hemisphere cryosphere falls between 0.3-1.1 w.m2.k, substantially larger than comparible estimates obtained from 18 climate models." Also considering the already changing weather patterns (Arctic Dipole) that effect the whole NH, what is next is going to be interesting. This rate of arctic sea ice loss, is well ahead of any computer predictions, what is the next 0.7C of global temperature rise going to bring? Oil speculation in the arcitc? A massive arctic wind farm to cool the arcitc? Potential climatic impacts and reliability of very large-scale wind farms C. Wang and R. G. Prinn Atmos. Chem. Phys., 10, 2053–2061, 2010 www.atmos-chem-phys.net/10/2053/2010/
       Moderator Response: [muoncounter] Flanner's work was discussed here.
90353. Rob Honeycutt at 09:15 AM on 31 March 2011
       Was Greenland really green in the past?
       Continuing the conversation from here. Grayman... Your comments about it being warmer in the past based on Greenland once being green are inaccurate. Please look at the website of Dr Jason Box and you can see what the modern temperature record is for Greenland. I would also highly suggest you read two papers on Greenland: Miller 2010... Temperature and precipitation history of the Arctic Alley 2010... History of the Greenland Ice Sheet: paleoclimatic insights I think you'll find the issue is vastly more complex that Vikings living in Greenland.
90354. Berényi Péter at 09:08 AM on 31 March 2011
       Of Satellites and Air – A Primer on Tropospheric temperature measurement by Satellite
       
       Re: Moderator Response: [DB] You identify a number of different topics which are best discussed elsewhere (like volcanoes, for example). If you wish to pursue them, do them elsewhere.
       I'd happily do that as soon as statements cloaked as an imperative from the article above like "And recall(!) that one of the major effects of AGW is a cooling of the Stratosphere" are also moved elsewhere. Until it's done, it remains perfectly appropriate to discuss the issue under this heading. What I have accomplished above was to show the truth-value attached to the proposition "one of the major effects of AGW is a cooling of the Stratosphere" is False. If the overall downward trend in the 32 year record of MSU/AMSU ch. 4 (TLS) is due to two step-like drops associated with well known volcanic events, as it is the case, and these eruptions were not anthropogenic ones, then one can not say the trend demonstrates "one of the major effects of AGW (Anthropogenic Global Warming)". Or can, but in that case you can't expect anyone to take it seriously.
90355. Rob Honeycutt at 09:00 AM on 31 March 2011
       Dana's 50th: Why I Blog
       grayman... If you're interested in discussing that particular subject (it being warmer in the past) we can post on the appropriate thread here.
90356. Stu at 08:54 AM on 31 March 2011
       2nd law of thermodynamics contradicts greenhouse theory
       damorbel, you seem insistent that the following 'fact' is of great import: - the energy of a photon can tell you the 'temperature' of the particle that emitted it Firstly, a single particle doesn't have a temperature, which is a statistical measure. It has an energy. This seems to have been explained to you before. However we are discussing gases, liquids and solids that, as has been explained, emit photons with a range of energies. These spectra are clearly the applicable measures when discussing radiative energy transfer. Next, from what people have said, it seems you believe that a photon emitted by a cooler object cannot be absorbed by a warmer object. Is this an accurate description of your stance?
90357. KR at 08:53 AM on 31 March 2011
       2nd law of thermodynamics contradicts greenhouse theory
       damorbel - "I asked you to define 'an object'." I cannot find such a request from you. But I'll answer it now that you have asked. I am speaking of relevant objects to the radiative greenhouse effect - the surface of the Earth, and the atmosphere. Both are large, ensemble objects, containing temperatures defined by thermal distributions, with thermal emission and absorption spectra defined by their component molecules. You cannot determine the temperature of such an object from a single photon. Single photons have a single energy, a single wavelength. Absorption likelyhood, the real question at hand, is based upon absorption spectra and individual photon energies. So I will ask again: Are you asserting that the possibility of absorption of a photon is not a function of that photon's energy and the potentially absorbing object's absorptivity spectra? DSL - rotfl.
       Moderator Response: [muoncounter] Oddly enough, damorbel used to agree:

       We are all familiar with the Planck spectrum, the amplitude of which is a function of the temperature, But taking one photon (with energy a function of frequency), or even one spectral component, does not represent the entire spectrum thus the temperature is not defined. Although a single photon has energy it does not have a temperature.

       See comment#70, this very thread.

       One could only describe this behavior as 'doublethink.'

90358. Paul D at 08:45 AM on 31 March 2011
       A Plan for 100% Energy from Wind, Water, and Solar by 2050
       Another new development, water 'battery': http://www.sciencedaily.com/releases/2011/03/110329134254.htm I have lost track of all these new ideas or improved ideas. I should keep a list! IMO if all these technologies were used wisely (a big ask for humans) we would have plenty of diverse sources and no real need for fossil fuels and a minor use of nuclear (until fusion is cracked).
90359. DSL at 08:44 AM on 31 March 2011
       2nd law of thermodynamics contradicts greenhouse theory
       When the fish is in the boat, it may tend to flop and wiggle violently, desperate to once again command the murky, muddy waters in which it has evolved to thrive.
90360. damorbel at 08:42 AM on 31 March 2011
       2nd law of thermodynamics contradicts greenhouse theory
       Re #904 KR you wrote:- "I asked about a photon and "...the temperature of the object that emitted it...". You replied regarding an individual particle, not an object temperature, strawman." I asked you to define 'an object'. Until you do, I don't know what you are talking about. So pleeaaase - do it now! For example you wrote:- "as there are multiple possible emitting down-transitions in electron orbitals for an excited molecule; it doesn't have to drop to ground state." Yes and these transitions can be (almost) anywhere in the EM spectrum where many other kinds of interactions can take place; but please let us stick to thermal matters, i.e. interactions that affect temperature.
       Moderator Response: [muoncounter] Pedantic requests, such as the definition of 'an object,' are exactly what have put this thread at over 900 comments, many mere attempt at distraction. If you have difficulty with definitions of everyday language, how can your definitions of scientific terminology be taken seriously?
90361. KR at 08:38 AM on 31 March 2011
       2nd law of thermodynamics contradicts greenhouse theory
       I referred to the Statistical Mode, not emitting, molecular, orbital, or other modes. Mistaking statistical mode for mean (average), or vice versa, is a common error. The rest of your post is rather irrelevant to the discussion.
90362. damorbel at 08:32 AM on 31 March 2011
       2nd law of thermodynamics contradicts greenhouse theory
       Re #898 KR you wrote:- "Actually, the peak of the curve is the mode, not the average; the two are not identical unless the distribution is symmetric. That's a fairly common error. " This is a better explanation of mode The relation of temperature to the peak is, once more, a critical one in quantum theory.
90363. KR at 08:31 AM on 31 March 2011
       2nd law of thermodynamics contradicts greenhouse theory
       damorbel - You have completely misread my question; I have to wonder if it's deliberate. You have two complete strawman arguments misstating what I asked. I asked about a photon and "...the temperature of the object that emitted it...". You replied regarding an individual particle, not an object temperature, strawman. An individual photon does not give the temperature of an emitting object. It doesn't even give the temperature of a single molecule, as there are multiple possible emitting down-transitions in electron orbitals for an excited molecule; it doesn't have to drop to ground state. Your answer is incorrect! "Does this mean that photon interactions do not need to be quantised?" - All photon interactions are quantum interactions, I never stated otherwise, strawman. The issue is whether photons emitted by a cooler object can be absorbed by a warmer object (ensemble temperatures), namely the atmosphere and the surface. Since an individual photon does not indicate it's emitting objects temperature, it's absorption depends only upon the absorptivity of the warmer object (determined by quantum interactions, which are off-topic) and the individual photon energies. You are really reaching here.
90364. Phil at 08:29 AM on 31 March 2011
       2nd law of thermodynamics contradicts greenhouse theory
       Darmorbel @901 "damorbel - Are you asserting that an individual photon (with a particular energy) can be used to identify the temperature of the object that emitted it, thus affecting it's absorption? " Yes I am, that is the basis of all quantum interactions. This is incorrect. A molecule of CO₂ (for example) has 4 (one doubly degenerate) vibrational modes. These occur at 2565 cm^-1 1480 cm^-1 and 526 cm^-1 If a molecule is in the 1st level excited bend state it can emit a photon at 526 cm^-1 But this reveals nothing about how many molecules are in excited states in the other vibrations or rotational excited states or the translational energy that the molecules have.
90365. grayman at 08:24 AM on 31 March 2011
       Dana's 50th: Why I Blog
       Moderator, thank you for the reply. I understand your concern for more questions and comments to it leading the to really being off topic, i was not trying for that just for the lead in and when i reread before submitting it looked good to me. I like the moderation stlye so far, good job and i will try to stick to adding citations , thanks again Rob, wrong, no but that is another topic for another day. I do try to look at all the evidence i can, and as any scientist or layman, with good common sense can attest to science can somtimes make things more complicated than they need to be. Engineers and designers are good about that. Moderator my apologies again.
90366. Phil at 08:19 AM on 31 March 2011
       2nd law of thermodynamics contradicts greenhouse theory
       darmorbel @897 Wein's displacement law, and the spectrum you allude to apply only to black bodies. Gases (such as CO₂ and H₂O) are not black bodies. The photons they emit will correspond to some of the frequencies of a black body, but their distribution of intensities will not. It is therefore not appropriate to talk of "temperatures" of photons. The energy of a photon is only related to the quantum states involved in the decay when that photon is emitted. Black bodies are "black" because they have a wide range of quantum states, merging into a continuous band. Otherwise they wouldn't be "black".
90367. damorbel at 08:17 AM on 31 March 2011
       2nd law of thermodynamics contradicts greenhouse theory
       Re #894 KR you wrote:- "damorbel - Are you asserting that an individual photon (with a particular energy) can be used to identify the temperature of the object that emitted it, thus affecting it's absorption? " Yes I am, that is the basis of all quantum interactions. Since 'an object' can be an individual particle, I don't see the diffiiculty. Further you wrote:- "Or that the possibility of absorption is not a function of photon energy and absorption spectra? If so, you are sadly mistaken." Does this mean that photon interactions do not need to be quantised? Well I don't accept that photon interactions can occur in a non quantised way; throughout the whole electromagnetic spectrum photon interactions with massive particles are always quantised; both on the macroscopic level (many particles described statistically) and at the individual particle level. NB Photons do not interaction with each other.
90368. KR at 08:16 AM on 31 March 2011
       2nd law of thermodynamics contradicts greenhouse theory
       Phil - "...the "back radiation" is emitted from molecules that have previously absorbed surface IR radiation (which must of the same frequency)." Actually, Phil, that's not correct. By my estimates each absorbing molecule at sea level collides with an absolute minimum of 1000 other molecules before it has a chance to emit, each modifying it's internal energy. (10^9 collisions per second, 10^-6 seconds minimum before emission) Emission spectra of the atmosphere depends on the temperature and makeup of the emitting gas - the varied energy level drops resulting in EM emission reflect the varied energies of the emitting molecules and their possible transitions through a radiating level. On average the photons from the surface will be of higher energy (shorter wavelength) than those from the air. But that's irrelevant to the fact that photons from the air are indeed absorbed by the surface, and that this absorption (by the 1st law of thermodynamics, conservation of energy) affects and slows the total, net energy transfer to the atmosphere and hence to space.
90369. Rob Honeycutt at 08:11 AM on 31 March 2011
       Dana's 50th: Why I Blog
       grayman... Note that I believe your comment was crossed out as much for being off topic as it was for being wrong. I highly suggest you take more time to read up on the science before applying common sense. Our human instincts can sometimes lead us astray when it comes to scientific issues. And this issue (climate change) has many whom wish to divert our eyes from the preponderance of evidence at hand. Read carefully. Be skeptical. Look at all the evidence before you decide.
90370. Phil at 08:07 AM on 31 March 2011
       2nd law of thermodynamics contradicts greenhouse theory
       darmorbel @895 We have been here before, the energy of a photon is available for electromagnetic particle interactions which are governed by quantum laws just the same, so it doesn't matter if the particle energy is defined in electronvolts or temperature, my use of the word 'temperature' to define the energy of a photon is common and justifiable. (In single particle interactions as in high energy physics individual particle energy is frequently just given in Joules. So you agree that photons have an energy, which is related to their frequency, and you agree that the "back radiation" is emitted from molecules that have previously absorbed surface IR radiation (which must of the same frequency). So you agree that your previous notion of surface IR radiation of having "warmer photons than the back radiation" is wrong !
90371. KR at 08:07 AM on 31 March 2011
       2nd law of thermodynamics contradicts greenhouse theory
       damorbel - "The diagram on this page Wien's displacement law (top right) has a temperature for each peak of the Planck curve - that is the temperature associated with the average energy of the photons. " Actually, the peak of the curve is the mode, not the average; the two are not identical unless the distribution is symmetric. That's a fairly common error. However, both mode and average are statistical values. You have now contradicted yourself; individual photons do not convey the temperature of the emitting object, as that requires a statistical ensemble.
90372. grayman at 07:59 AM on 31 March 2011
       Dana's 50th: Why I Blog
       Hey back Dana, I will read the post you recommend but first to the moderator, that section you crossed out was not a question or being off topic for the thread, just a lead in to the comment below it. Thank you for putting it in paragraph form, i will try to be more mindful of that in the future.
       Moderator Response:

       [DB] First and foremost, as a first-time poster here we all definitely want you to feel at home here. And Dana's post does indeed touch upon a variety of topics. The part struck-out, in and of itself, is contrary to the current understanding of things (without a source citation for others to follow). I didn't then want other commenters here to follow those bits up with further questions that might then detract from the topic of this thread. That was my point.

       Feel free to disagree with the thread posts, but please use source citations and/or links to help others understand the substance behind why you're disagreeing. Tips on composing comments can be found here.

90373. damorbel at 07:58 AM on 31 March 2011
       2nd law of thermodynamics contradicts greenhouse theory
       Re #893 Phil you wrote:- " 3. The temperature of the black body can be calculated using the frequency of the most common (or more intense) photons. This is notated as υmax indicating the frequency at which there is maximum intensity. 4. The photons of this frequency do not have this, or any other, temperature." The diagram on this page Wien's displacement law (top right) has a temperature for each peak of the Planck curve - that is the temperature associated with the average energy of the photons.
90374. KR at 07:57 AM on 31 March 2011
       2nd law of thermodynamics contradicts greenhouse theory
       damorbel - I am quite frankly appalled by your last post - I suspect I am not alone. The photoelectric effect (and in fact your entire post on it here) is a complete red herring, irrelevant to absorption of thermal energies. QED is the basis of absorption spectra determination, but that's a different question - also irrelevant. You are misusing "temperature" - particles have energies and velocities, photons have energies, an ensemble of particles have temperature, an ensemble of photons have spectra, the last of which can (with some idea of the emitting object spectra) be used to identify emitting object temperature. Your personal re-definition and misuse of a term is not in any way a compelling argument against thermodynamics. Do you have any answer to the two questions I posed at the end of my last post? The ones actually relevant to energy exchanges between cooler and warmer objects (atmosphere and surface)? Questions on the actual subject of this thread?
90375. Albatross at 07:50 AM on 31 March 2011
       Arctic Ice March 2011
       Scaddenp @48, Well, they actually started off claiming that the loss was not evening happening and that is was "recovering". But as for the rest of your post....right you are.
90376. damorbel at 07:41 AM on 31 March 2011
       2nd law of thermodynamics contradicts greenhouse theory
       Re #891 KR you wrote:- "Absorption does not require photoelectric emission of an electron; that's a completely different question - Herring." That was the point of departure for quantum physics in 1905, something I made quite clear. But it is now generally accepted that all electromagnetic interactions take place in the domain covered by quantum physics - it is called quantum electrodynamics (QED) http://en.wikipedia.org/wiki/Quantum_electrodynamics But you are making much of the statistical distribution of energies in a given sample of particles with a given temperature. To start with, to have a defined temperature the particles must be in equilibrium, the average energy must be steady. In this condition the average energy is the total energy of all particles in the sample divided by the number of particles in the sample. But there is no need to have a certain number of particles to make a sample, so one particle with the same energy as the average energy of all the particles also has the same temperature as the whole sample. you wrote:- "Individual photons have energies, not temperatures - False statement" We have been here before, the energy of a photon is available for electromagnetic particle interactions which are governed by quantum laws just the same, so it doesn't matter if the particle energy is defined in electronvolts or temperature, my use of the word 'temperature' to define the energy of a photon is common and justifiable. (In single particle interactions as in high energy physics individual particle energy is frequently just given in Joules. You wrote "Estimates of object thermal emission temperatures require a spectra (statistical knowledge) and some idea of the emission spectra. An individual photon is incapable of supplying sufficient information - Incorrect statement and herring" What do you mean by 'object'? (First line above.) Is a particle not an 'object'?
90377. scaddenp at 07:36 AM on 31 March 2011
       Arctic Ice March 2011
       Actaully as Arctic situation gets worse (as predicted by climate theory), it becomes a priority for denialists to find reasons for trivializing it. So far we have "its not nothing to do with global warming" (with side dose of "its a natural cycle"), "it not important (only a small area)", a lame attempt at "but its happened before recently". I am guessing we will soon get "it good for us - opens up oil/gas reserves and new areas of arable land". Any other bets?
90378. KR at 07:32 AM on 31 March 2011
       2nd law of thermodynamics contradicts greenhouse theory
       damorbel - "one particle with the same energy as the average energy of all the particles also has the same temperature as the whole sample. " (Emphasis added) Flatly wrong. That photon (the subject of the discussion) will have the average energy of the whole sample. Any individual photon can come from anywhere in the emission spectra of the object (high to low), and from any individual photon there is no fixed determination of temperature. damorbel - Are you asserting that an individual photon (with a particular energy) can be used to identify the temperature of the object that emitted it, thus affecting it's absorption? Or that the possibility of absorption is not a function of photon energy and absorption spectra? If so, you are sadly mistaken. Boltzmann thermal distributions are off-topic distractions. Energy transfer from cooler to warmer objects is the issue raised in this thread.
90379. Albatross at 07:30 AM on 31 March 2011
       Arctic Ice March 2011
       John @45, "Almost always, just those few words brings greater illumination than days of numerous minds shining light on things irrelevant." I might regret asking this, what do you believe to be "irrelevant", and why? Please provide some science and citations to back-up your assertions/belief, otherwise you are just pontificating.
90380. dhogaza at 07:27 AM on 31 March 2011
       Arctic Ice March 2011
       

       over the years I have often, as I'm sure you have done so as well, call for all to pause and get back to basics in order to regain perspective, just as your brief observation so ably demonstrates.

       Here's a basic: the arctic plays a large role in the weather of the NH. Just look at last winter ...
90381. dana1981 at 07:26 AM on 31 March 2011
       Muller Misinformation #1: confusing Mike's trick with hide the decline
       And Wolf, if you still disagree, I would ask you to explain how the statements I outlined in my Comment #87 aren't factually wrong.
90382. scaddenp at 07:25 AM on 31 March 2011
       Arctic Ice March 2011
       When thinking about arctic seaice as indicator, perhaps we should also consider this: When was the last time there was a ice-free summer at the pole (and I dont mean polynas)? Melting in Greenland is actually more important but arctic ice gets a lot of attention because of what the models predict (they underestimate loss) and the view that it is the "canary in the coal mine".
90383. dana1981 at 07:24 AM on 31 March 2011
       Muller Misinformation #1: confusing Mike's trick with hide the decline
       Wolf #91:

       "Nothing in Mullers statements is factually innacurate, just biased."

       Sorry, I can't agree. I refer you back again to Comment #87, in which I showed two indisputably factually inaccurate statements. They are both wrong. Period. As I've said, I agree Muller has a valid point about the WMO graph. As I've also said, I don't really care, and don't see why Muller cares, because it was a cover on an obscure report that basically nobody even knew about or saw until the emails were stolen in '09. Frankly, the only reason Muller cares is because of the errors he's making. He's inflating the importance of the obscure report cover.
90384. Phil at 07:24 AM on 31 March 2011
       2nd law of thermodynamics contradicts greenhouse theory
       Wein's displacement Law: 1. A black body emits photons at range of frequencies. 2. The number of photons emitted (otherwise known as the intensity) at any particular frequency will vary. The plot of the intensity versus the frequency is the "black body spectrum" 3. The temperature of the black body can be calculated using the frequency of the most common (or more intense) photons. This is notated as υ_max indicating the frequency at which there is maximum intensity. 4. The photons of this frequency do not have this, or any other, temperature.
90385. damorbel at 07:21 AM on 31 March 2011
       2nd law of thermodynamics contradicts greenhouse theory
       Re #889 KR you wrote:- "Any argument that photons from a cool object will not add to the internal energy of a warmer object they impinge upon due to their origin are specious; there is no such information encoded in the energy of an individual photon" But you are making much of the statistical distribution of energies in a given sample of particles with a given temperature. To start with, to have a defined temperature the particles must be in equilibrium, the average energy must be steady. In this condition the average energy is the total energy of all particles in the sample divided by the number of particles in the sample. But there is no need to have a certain number of particles to make a sample, so one particle with the same energy as the average energy of all the particles also has the same temperature as the whole sample.
90386. KR at 07:21 AM on 31 March 2011
       2nd law of thermodynamics contradicts greenhouse theory
       damorbel - Quite a kettle of fish in that post, which is to say red herrings. I note that by comparing it to facts: Absorption does not require photoelectric emission of an electron; that's a completely different question - Herring. Individual photons have energies, not temperatures - False statement. Estimates of object thermal emission temperatures require a spectra (statistical knowledge) and some idea of the emission spectra. An individual photon is incapable of supplying sufficient information - Incorrect statement and herring. "...absorbing takes place at the particle level. Further, to be absorbed a photon has to encounter the absorbing particle in the correct phase etc." - Herring. My statement in this post regarding absorption points out that if the absorption spectra of an object has a value of 0.8 for 6 micron photons, it has an 80% chance of absorbing any 6 micron photon, no matter the origin. - Your post is flatly, completely, wrong.
90387. dana1981 at 07:15 AM on 31 March 2011
       Dana's 50th: Why I Blog
       hi grayman, and thanks. Please see Greenland used to be green. I agree with you on the EPA, they've done a good job.
90388. scaddenp at 07:15 AM on 31 March 2011
       A Plan for 100% Renewable Energy by 2050
       gilles - indeed. Half the known coal reserves. Actually I think the about of CO2 in atmosphere is still dangerous with half the coal burn of A12 scenario.
90389. damorbel at 07:07 AM on 31 March 2011
       2nd law of thermodynamics contradicts greenhouse theory
       Re #887 (& 849) you wrote:- "identifying the temperature of an emitting object requires a statistical analysis of a spectra of photons" Temperature is the property of an individual particle since it is the measure of the energy in that individual particle. I have mentioned this before and nothing about statistics is necessary to establish this. What you are thinking of is the temperature of an ensemble of many particles that are interacting strongly with each other (in equilibrium) so that the particles have a distribution of energies, the distribution is called the Boltzmann distribution. Your #849 directly contradicts the basis of quantum theory. You write:- "An object, at 20C, has an 80% absorptivity for 6 micron photons" For a start - absorbing takes place at the particle level. Further, to be absorbed a photon has to encounter the absorbing particle in the correct phase etc. But, according to quantum laws, the photon cannot be absorbed at all unless it has sufficient energy E (E=hv, 'h' is Planck's constant and 'v' is the characteristic frequency) This was the basis of Einstein's 1905 paper on the Photo-electric effect It is an experimentally observed fact that photons must have sufficient energy i.e. a sufficiently high equivalent temperature (discovered from the Wien displacement law) before they can be absorbed and cause an electron to be emitted. This applies in all areas of physics and chemistry, ozone is formed when O2 is split into 2 x O atoms, with light; but this only happens with ultraviolet light (UV) shorter than 0.2microns
90390. KR at 07:02 AM on 31 March 2011
       2nd law of thermodynamics contradicts greenhouse theory
       To fill out my last post: Any argument that photons from a cool object will not add to the internal energy of a warmer object they impinge upon due to their origin are specious; there is no such information encoded in the energy of an individual photon, absorption is based solely upon that energy and the absorption spectra of the impinged object. Hence any such "2d law" energy transfer objections are clearly wrong, and based upon a misunderstanding of the physics involved.
90391. grayman at 07:00 AM on 31 March 2011
       Dana's 50th: Why I Blog
       Hi Dana, congradulations on you 50th article and you will have many more to come. As we do not agree on the causes of the warming, i will not get into that, but the economics of mitigation IMO will be greater than most estimates from any person on the planet. Knowing that most parts of the world were warmer than today as evidenced by Greenland glacier melting and finding viking settlements there and glacial retreat in Swiss mountains and finding whole villages that were swallowed by the glacier is very compelling evidence to me in that respect. (off-topic) Adaption will be easier than anybody can really understand. The biggest cost to any of it will be moving the millions of people away from the coasts of the continents with sea level rise, which even with a 3c rise in temps would take many 100s of years if not 1000 years. Rob, how are you? I agree that the chinese are starting to do what they can about the working conditions of the people but IMO thier biggest problem is the pollution that they are creating just like us and Europe in the past 100 to 2oo yrs. The USA came up with the EPA to combat this problem and they have done a very good job of cleaning up the smokestacks and enviroment of this land and we all know we have just strached the surface in that repect, Right Dana. Personally i see a revolt in the future, all over the world just like the middle east because of the same things they have, ie, corruption, no employment, more corruption, more have nots than haves. Carbon pricing or trading will put untold billions or trillions in the bankers pockets with no real impact on the climate IMO. We can study it till we are blue in the face, but face, greed is a human condition that can not be stopped much less legeslated out of the globe. I am know scientist as Dana and Rob know just a man with good common sense who has travelled the world and seen all this thru out the world. Again congrats on the 50th article Dana, look forward to more.
       Moderator Response:

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90392. Alexandre at 06:58 AM on 31 March 2011
       Arctic Ice March 2011
       Jay #35 Ok, so NOAA is not reliable and reputable enough to provide this kind of data (please tell me if I unvoluntarily misrepresent you). I do not agree, but that's rather personal. NCAR seems to endorse the same data (Albatross' ref). From which much more reliable source than these did you get the information that that period was warmer?
90393. KR at 06:55 AM on 31 March 2011
       2nd law of thermodynamics contradicts greenhouse theory
       Moderator/DB - I believe damorbel's last comment actually was on topic, if wildly incorrect in it's implications: multiple assertions have been made that the photons from cooler objects hitting warmer ones do not reach / don't get absorbed / are turned away by a restrictive bar-room bouncer after being carded, in violation of the 1st law of thermodynamics and the physics of absorptivity for individual photons. So while (as I said) quite incorrect, it is somewhat relevant - if only to highlight the errors made by "2nd law" objections.
       Moderator Response: [DB] Apologies then. My initial read found context for his linked reference lacking in his comment. Sometimes one because conditioned to expect certain things...
90394. Bob Lacatena at 06:37 AM on 31 March 2011
       Acidification: Oceans past, present & yet to come
       2, Mike, 3, Rob, The authors of the study used (emphasis mine) "larvae grown under near pre-industrial CO₂ concentrations (250 ppm)"... that is, the statement isn't that pre-industrial levels were 250 ppm, but rather that 250 ppm were used as the benchmark to simulate growth at about pre-industrial levels. Reading the materials and methods section of their paper, it seems that coming up with a sea-water-CO₂ "soup" is not as simple as mixing ingredients in the right proportions. They got a medium which they considered suitable, then measured the CO₂ levels in that medium (in fact, the actual levels were 247 ±6 and 244 ±4) to see what they were working with. Futzing around to get it to exactly 280 ppm probably wasn't worth the time and effort, nor truly relevant to the study.
90395. Daniel Bailey at 06:17 AM on 31 March 2011
       Arctic Ice March 2011
       Adding to the current discussion, one can look at the current trend in Arctic Sea Ice cover in several ways: 1. By trend in winter sea ice thickness: Image courtesy ICESAT/NASA 2. By trends in ice extent and area by month: Image courtesy LHamilton@Neven's Arctic Sea Ice blog 3. Or by looking at trends in ice edge by month by latitude: Image courtesy LHamilton@Neven's Arctic Sea Ice blog (Edit) To sum: 1. Arctic sea ice thickness is in a multiyear decline, led primarily by the loss of multiyear (old & thick) ice 2. Arctic sea ice extent and area have declined in every month of the year 3. The southernmost ice edge has retreated northward in every month of the year. The trend (the dwindling of the Arctic sea ice is like an ice cube melting away in your favorite drink) should be clear by now to all with eyes that see (and ears that hear)... (end edit) The Yooper
90396. Rob Painting at 06:14 AM on 31 March 2011
       Acidification: Oceans past, present & yet to come
       Mike, no idea why the authors chose that value, and (without checking) how far back in time that would be. Older papers had immediately pre-industrial at 260-280ppm. But whatever the case may be, the experiments indicate things have already taken a turn for the worse.
90397. KR at 06:12 AM on 31 March 2011
       2nd law of thermodynamics contradicts greenhouse theory
       damorbel - Your reference clearly demonstrates that identifying the temperature of an emitting object requires a statistical analysis of a spectra of photons, meaning that an individual photon does not by itself identify the temperature of the source. Which therefore indicates that your assertion here is incorrect. See my earlier post on photon absorption in that regard. Photons, unlike Arizonan citizens, do not carry ID cards indicating their origin. Do you have any comments on the actual issue of this thread, the (observed) exchange of energies between cooler and warmer objects and the implications thereof toward the radiative greenhouse effect?
90398. climatewolf at 06:09 AM on 31 March 2011
       Muller Misinformation #1: confusing Mike's trick with hide the decline
       Hi dana1981, "You're basically saying that even though what Muller said was wrong, he was right about the underlying science" Nope, I am not saying this at all. What I am saying is that in the presentation from Muller he used this WMO cover graph and a paraphrase of Jones email to demonstrate what HE sees as a distortion of facts. I personally have not at this point drawn a conclusion. My issue with this particular OP is that in presenting the full and complete facts, it doesn't support the statement that Muller has his facts wrong. Nothing in Mullers statements is factually innacurate, just biased. Mr Cook even agree that this particular graph was rightly criticised for not making it clear which data was reconstruction and which instrumental. So to clarify for me as I am failing to understand your point. Please can you explain when Muller is refering to this specific graph and this specific email where Jones cleary states he has used the graphing "trick" of Mann to add the instumental records to the Briffa reconstruction from 1961 AND removed the reconstruction data from that point on, did Muller incorrectly state the facts? Please note, I am not defending Muller for his bias or fairly obvious attack on Mann, I just think if we are going to hold ALL scientists in this debate up to scrutiny on facts, it must be applied equally. I think Muller is making a valid point in regards that graph ALONE. The fact that he uses it to score "points" is pretty low as far as I am concerned, and the fact he doesn't put this graph into context with other or talk about the divergence problem in any detail makes this a one sided presentation. In fairness, in the 2nd link, he does at least point out that his view is one sided and there is no "fair trial" as such. Anyway to be clear dana1981 et al. I am not suggesting the use of this "trick" was in any way wrong, or undocumented, I am debating the semantics of this single particular post. Regards Wolf
90399. coolaun at 06:08 AM on 31 March 2011
       Skeptical Science now an Android app
       It's great to have all these arguments at my fingertips. The next time a climate change denier annoys me, I can actually pull the facts out of my pocket. The app is well designed, but here are two things I hope you can change: - It's very annoying that the app doesn't remember the text magnification: each time I open an article I must click again on the "magnify" icon to set the text at a size I can comfortably read. - It takes up a lot of space on the internal drive. There really should be an option to move it to the SD card.
90400. damorbel at 06:03 AM on 31 March 2011
       2nd law of thermodynamics contradicts greenhouse theory
       Re 885 Philippe Chantreau you write:- "I'm still waiting on how the energy of a photon is affected by the temperature of the source." I think it is sumarised inWien's displacement law

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