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All IPCC definitions taken from Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Annex I, Glossary, pp. 941-954. Cambridge University Press.

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Comments 101451 to 101500:

  1. The 2nd law of thermodynamics and the greenhouse effect
    AWoL @ 155: I had prepared a rather detailed response, and mis-clicked on "click for tips &c." when I meant to preview the post. So consider this the poor cousin alternative. So I'll just suggest checking out the threads on this site: - Empirical evidence for warming. - Empirical evidence of human causality. And I believe any further discussion on CO2 as a trace gas should occur in a thread such as this one. The great thing about this blog is its reliance on - and its frequent refernece to - the peer-reviewed literature in the various threads regarding the evidence surrounding AGW. I brought up quantum & relativistic physics as examples of areas which often require starkly non-intuitive thinking to bring understanding, the sort of thinking where relying on instinct can lead one astray. I am sure there are many excellent sources of information on them, both online and in print.
  2. How to explain Milankovitch cycles to a hostile Congressman in 30 seconds
    scaddenp@48. The Milankovitch theory does have problems. Do I think it is wrong? From my research, and this was yes....dated....I came away with thinking it was not wrong nor correct. I have not read the Crowley paper and would be most interested in reading it. The level of proof a few years ago was quit thin. In ref to the 3.7W/m2....I am not comfortable with that number. I know it is cited in IPCC, but it is also reflective of what the sensativity is. And that is still a wide open question.
  3. How to explain Milankovitch cycles to a hostile Congressman in 30 seconds
    scaddenp: Do you have an open link to Crowley? Thank you Yooper.
  4. Positive feedback means runaway warming
    #31: "The rate of release from hydrate deposits is limited by ..." Nothing limited about these numbers: Gas escape features off New Zealand: Evidence of massive release of methane from hydrates Multibeam swath bathymetry data ... show gas release features over a region of at least 20,000 km^2. Gas escape features, interpreted to be caused by gas hydrate dissociation, include an estimated a) 10 features, 8–11 km in diameter ... If the methane from a single event at one 8–11 km scale pockmark reached the atmosphere, it would be equivalent to ∼3% of the current annual global methane released from natural sources ... Full paper, with graphics, available here.
  5. How to explain Milankovitch cycles to a hostile Congressman in 30 seconds
    Yes, Camburn, (though your source may be dated), but I was asking for problems where there are not multiple workable answers to the problem and merely difficulties constraining which works best. This is common issue in paleo sciences. Personally I think Crowley has nailed transition problem. Again, are you seriously looking at the milankovitch cycle and glaciation and saying you think milankovitch theory is wrong? Also, what relevance do you think any of milankovitch forcings have to climate in human terms? How much effect do you get from 0.25W/m2 change in one part of globe over one hundred years from orbital variation compared to 3.7W/m2 over whole globe in same time period?
  6. An Even Cloudier Outlook for Low Climate Sensitivity
    @HUR: "I think the point is that people are concerned about the censorship over at RC" Deleting troll posts is hardly censorship. There's no law forcing private websites from cleaning out their comments sections. Some websites just have lower tolerance for trolling, that's all. And, in case you wonder, I *do* consider that repeating the same old debunked "skeptical" argument is trolling at this point.
  7. An Even Cloudier Outlook for Low Climate Sensitivity
    #44: "he thinks sensitivity is around 1 to 1.5°C for 2xCO2" But there's already been an ~0.6C increase since the 70s, with nowhere near a doubling in CO2 (1970=325ppm, 2010=388ppm). How are they getting away with what is the equivalent of 'voodoo economics'? #45: Eric, you're correct!
  8. How to explain Milankovitch cycles to a hostile Congressman in 30 seconds
    Re: Camburn (44) Helpful tip:
    1. If your intent is to engage intellectually gifted people (yes, that lets me out) and 2. Spark meaningful dialogue on areas you feel have large areas of uncertainty
    then you may want to re-think your approach a bit. Visitors who pose questions framed with thought, and with cited sources, get a lot more interaction and positive attention. Or you could keep on posting unsupported assertions. Being a glass-half-full person, I opt for positive dialogue myself. I feel I get much better and informative conversations that way (and therefore learn more). Your Call. [ - Edit: OK, I see you added some bits. If you would delineate your position relative to the consensus on each, and also let on where you base your differing opinion (what source do you have for that), you'll find a more helpful and fulfilling interaction. End Edit - ] The Yooper
  9. How to explain Milankovitch cycles to a hostile Congressman in 30 seconds
    Ok: 1.The 100,000 year problem 2. The 400,000 year problem 3. The stage 5 problem. 4. The transition problem. And these are only a few of the problems.
  10. An Even Cloudier Outlook for Low Climate Sensitivity
    muoncounter, it's only a nitpick but only the current interglacial was named the Holocene (I have no idea why). They named the prior one the Eemian. I'm sure they have strange names for the rest of them too.
  11. How to explain Milankovitch cycles to a hostile Congressman in 30 seconds
    Now what exact problems are you talking about? The issues that I am aware of have to do with multiple possible solutions to unconstrained problem (eg sources of CO2, 100,000 year problem) rather than an inability to provide explanatory power. And these are hardly being ignored (look at any issue of Quaternary Science) - just not enough data yet to tie things down. While I know that correlation doesnt equal correlation, the match of the milankovitch cycles to ice-age cycle is so striking that surely you arent suggesting that these arent the dominant forcing? The fine details of the mechanism are another story.
  12. An Even Cloudier Outlook for Low Climate Sensitivity
    muoncounter #42 - yes, that's a common argument against the Lindzen theory. If climate sensitivity is really 0.3-0.5°C as Lindzen claims (the former on Watts' blog, the latter in LC09 linked in the article), then glacial-interglacial transitions are pretty much impossible to explain. It amazes me that any climate scientist can argue sensitivity is so low with a straight face. Spencer is more reasonable, I believe he thinks sensitivity is around 1 to 1.5°C for 2xCO2.
  13. An Even Cloudier Outlook for Low Climate Sensitivity
    I've read both Spencer's blog and the email exchange between Spencer and Dessler, and honestly I can't figure out what Spencer is trying to argue. He says Dessler is wrong, but never clearly explains why. He claims it's an oversimplification to say that he's claiming cloud changes cause ENSO, but he never clearly explains his theory. Basically it seems to boil down to "Clouds are complicated beasts". Well gee, thanks for clarifying! But the bottom line is that if cloud changes aren't causing temp changes via ENSO changes, then they're acting as a temperature feedback, and Dessler's approach is correct, because ENSO is dominating the short-term temp changes.
  14. An Even Cloudier Outlook for Low Climate Sensitivity
    #38: "it's the anti-science side saying "it's not a mystery, net cloud feedbacks are negative and at a magnitude that will counteract CO2-forced warming" Wait a sec, is that really what they're saying? Has anyone called 'em on it? As in, why didn't these miraculous clouds stop the 5 Holocene warmings of 6 degrees or more?
  15. The 2nd law of thermodynamics and the greenhouse effect
    AWoL, the answer is "false!" to your question "The downward radiation can be measured but my understanding, at present, is that has no effect, as its frequency is too low to raise the temperature of matter at a warmer temperature.....2nd Law of Thermodynamics...true or false?" Your rationale contains several misconceptions. The frequency of the downward radiation is not by itself the determinant of the resulting temperature of the matter that absorbs it. The temperature of that matter at a given moment in time is a consequence of the energy that matter contains at that time. The matter does not know or care how it got that energy. If a single photon of frequency F is absorbed by that matter, the matter's energy increases by a corresponding amount E. Imagine that instead the matter is hit by two photons each having a lower frequency such that they each have only half that energy (i.e., E/2). If those two low-energy photons both are absorbed by the matter, the matter will absorb the same energy E (i.e., 2 x E/2 = E) that it would get from absorbing the single original photon that carried energy E (i.e., 1 x E = E). The temperature of the absorbing matter is irrelevant to whether the matter absorbs any of those three photons. But even the total amount of energy absorbed is not the sole determinant of the matter's temperature. At the same time that energy is being absorbed, energy is being emitted by the matter. If every time energy E is absorbed, coincidentally that exact same amount of energy E is emitted simultaneously, then the net change in the energy contained by the matter is 0 (i.e., +E + -E = 0). If the amount of energy contained by the matter does not change, then the temperature of the matter does not change. If instead the matter is absorbing 0 energy and is emitting E energy, the matter's contained energy is reduced by E (i.e., +0 + -E = -E), which means the matter's temperature reduces. If instead the matter is absorbing E and simultaneously emitting only 70% of E, then the matter's net change in energy is an increase of 30% of E (i.e., +E - .7E = +.3E). That last sentence is why the greenhouse gas effect does not violate the 2nd law of thermodynamics. Matter on the surface absorbs some of the photons emitted by the Sun, thereby acquiring energy. The temperature of that receiving matter has no influence on whether a particular solar photon is absorbed, and therefore has no influence on whether that photon's energy is added to the energy the matter already has. Matter on the surface also absorbs some of the photons that are emitted by air molecules. The temperature of the receiving matter has no influence on whether each of those particular air-sourced photons is absorbed. The surface matter blindly absorbs photons from both sources. Does the surface matter's temperature increase when those absorptions happen? There is no way to know unless we also know how much energy the matter is losing at the same time, as I described above. One name for that is the surface "energy budget"--energy gained minus energy lost equals net energy change. If the surface matter is emitting more energy than it is gaining, its current energy content falls, so its temperature falls, despite the fact it is absorbing energy. If the surface matter is emitting less energy than it is gaining, its current energy content rises, so its temperature rises. Crucially, the gaining of energy is that total from all sources--Sun and air, radiation and conduction. The fact that the source of some of that energy is really hot (Sun) and the source of some of the energy is kind of cool (air) has played no role. Photons do not carry source credentials. It happens that the temperature of the surface matter does affect how much energy the matter emits. Starting from equilibrium (balanced budget: energy in = energy out), when extra energy comes in, the total energy content becomes higher than a moment before, which means the temperature is higher, which leads to the emission of more energy. If that extra incoming energy was just a single pulse, then the extra outgoing continues until all that pulse's energy has gone out. In the absence of an ongoing stream of "extra" incoming energy, the matter's energy then is again at equilibrium. In this pulse case, the matter's temperature only temporarily increased. The temperature affected the energy budget, but only by affecting the amount of outgoing energy, not by affecting the amount of incoming energy. If instead of a single pulse of "extra" incoming energy there is a steady stream of extra incoming energy--a step up in the incoming energy--then the temperature increase also is a step up, and the temperature stays at that higher temperature, once again at equilibrium with the new (larger amount) of incoming energy matching the new (larger amount) of outgoing energy. The energy absorbed during the step-up itself remains inside the matter; the energy gotten during the step up remains "trapped" by the matter. Still, the temperature of the matter has no influence on the amount of energy absorbed; temperature affects the energy budget's bottom line only because it affects the energy budget's outgoing part of the equation. Greenhouse gas warming of the surface works as that last paragraph describes. Where exactly in that mechanism do you see an opportunity for the 2nd law to interfere?
  16. An Even Cloudier Outlook for Low Climate Sensitivity
    "it criticizes the method they used as one which can be fiddled to cherrypick convenient starting or ending points." In particular you can choose starting and ending points and get just about any result you want, and they gave no reason for the choice of their particular start/end points. Also, HR, you've only given one definition of "fiddled", there are common definitions that don't assign a malignant motive to the act, such as this one: "to touch or manipulate something, as to operate or adjust it; tinker (often fol. by with ): You may have to fiddle with the antenna to get a clear picture on the TV." Clearly saying a mathematical process can be "fiddled" uses the word in the sense of "to tinker with".
  17. An Even Cloudier Outlook for Low Climate Sensitivity
    "Reading RC and Spencers own blog then this statement seems to be a misrepresentation. Spencer does not support a hypothesis that clouds cause ENSO, in fact he clearly refutes it. " No, he's said "it's an oversimplification of my argument". If you follow his argument, it's essentially what it boils down to, though Dressler's being a bit snarky. He quite clearly states that he believes that the accepted science gets causuality backwards ...
  18. An Even Cloudier Outlook for Low Climate Sensitivity
    "I think the point is that people are concerned about the censorship over at RC, and feel more free to ask questions here." Tough. He's there. Ask away. Now, if you ask something like "why don't you acknowledge that your paper is fraudulent and all of climate science is a fraud?", it's not going to show up. If you ask a rationale question about the paper, nicely, I'm sure it will.
  19. An Even Cloudier Outlook for Low Climate Sensitivity
    Camburn: "You are catching on. It is STILL a big mysterday." It's been a big mystery forever, and an openly acknowledged mystery. I've been aware of it for years, as has been anyone following climate science. It's not the science side saying it's not a mystery, it's the anti-science side saying "it's not a mystery, net cloud feedbacks are negative and at a magnitude that will counteract CO2-forced warming and feedbacks such as water vapor". Spencer doesn't talk about a "mystery", Spencer talks about *certainty* that his magic negative cloud feedback will save us. However, the preponderance of evidence shows that the net feedback will be slightly positive. Slightly negative's not off the table, but there is no sound evidence for the kind of magic feedback that folks like LIndzen and Spencer claim will kick in "real soon now" (i.e. as temps rise slightly) and forestall warming. Statements like this: "Thank you for posting this. You beat me too it. There are methodology problems with Dr. Dressle's paper." Are easy to make. I'll make an easy statement, too: put up or shut up. Seriously. Go show Dressler where he's wrong.
  20. An Even Cloudier Outlook for Low Climate Sensitivity
    HR #33 - the article says "...(Lindzen and Choi 2009) has been heavily criticized for using a method that can be fiddled...." It doesn't say they necessarily fiddled with the data, it criticizes the method they used as one which can be fiddled to cherrypick convenient starting or ending points.
  21. An Even Cloudier Outlook for Low Climate Sensitivity
    #13 Thanks Robert (and Daniel). It was approachable and facsinating.
  22. An Even Cloudier Outlook for Low Climate Sensitivity
    29 & 31 dhogaza That's funny. I think the point is that people are concerned about the censorship over at RC, and feel more free to ask questions here.
  23. An Even Cloudier Outlook for Low Climate Sensitivity
    "Spencer has countered this by arguing that ENSO changes are caused by clouds, and thus the response of clouds to surface temperature changes cannot be inferred. Dessler argues that Spencer's hypothesis that ENSO is caused by clouds is new and untested" Reading RC and Spencers own blog then this statement seems to be a misrepresentation. Spencer does not support a hypothesis that clouds cause ENSO, in fact he clearly refutes it. This has nothing to do with a Spencer hypothesis and seems to be a mis-reading by Dessler. I think it's an important point given the way Dessler uses this point to try to isolate Spencers work from the mainstream.
  24. How to explain Milankovitch cycles to a hostile Congressman in 30 seconds
    And what about the problems with the Milankovitch theory? Are they to be ignored? It does not match climate nearly as well as some would think.
  25. An Even Cloudier Outlook for Low Climate Sensitivity
    Just one small point. It keeeps jumping out at me every time I read the above article. "fiddled" - Definition 'The act or an instance of cheating or swindling; a fraud.' SkSci Comments Policy "No accusations of deception. Any accusations of deception, fraud, dishonesty or corruption will be deleted. This applies to both sides. Stick to the science. You may criticise a person's methods but not their motives." It seems like a poor choice of words that's breaking the sites own rules, it could do with being changed. "Lacks robustness" sound more in the spirit of scientific criticism.
  26. An Even Cloudier Outlook for Low Climate Sensitivity
    dhogaza@31: You are catching on. It is STILL a big mysterday.
  27. The 2nd law of thermodynamics and the greenhouse effect
    damorbel "Um, well, yes; very interesting. Tell me do you also reject the conclusions that have been drawn in consequence of the failure of the 'caloric theory' to match scientific observations, such as the 1st law of thermodynamics, the conservation of energy etc.?" non sequitur "In #160 I was drawing a distinction between internal energy which causes a temperature change (heat) and internal energy that doesn't cause a temperature change, sometime (mistakenly) called 'latent' heat. How do you draw a distiction between the two?" you where not talking about this: "Let there be no doubt about it, heat is energy density where the energy is in the form of molecular motion, it is to be found in all materials above 0K. ". Please don't try to move away from what you said, it's pointless. As I alread said, check any textbook. Or you think you know better than textbooks?
  28. An Even Cloudier Outlook for Low Climate Sensitivity
    Oh, I misunderstood 28, he's quoting Dr. Dressler. But serious, why not just ask him?
  29. It's albedo
    Hey Ned, What is "s" in your equation for energy emitted? Thanks, David
  30. An Even Cloudier Outlook for Low Climate Sensitivity
    Or, ask him from details at http://atmo.tamu.edu/profile/ADessler
  31. The Climate Show #3: Cancun and cooling
    Daniel@5: Thank you....That was the intent.
  32. An Even Cloudier Outlook for Low Climate Sensitivity
    "There is something here for a lot of people to learn from. Admittedly I'm finding it difficult to find information to look into this. Would anyone here be able to explain how Andy came to 20W/M*2." GO ASK HIM AT REAL CLIMATE. C'mon people, are you afraid that your debunkers might not really be debunking anything at all? "In our present climate, the reflection of solar energy back to space dominates, and the net effect of clouds is to reduce the net flux of incoming energy at the top of the atmosphere (TOA) by ~20W/m*2, as compared to an otherwise identical planet without clouds." If this were known to be true, then the net feedback from clouds wouldn't be the big mystery it is acknowledged to be, would it?
  33. An Even Cloudier Outlook for Low Climate Sensitivity
    On another site we are discussing Andy Desslers paper. A rather sharp guy CBACBA is challenging where Andy gets his number for this below. ##################################################################### In our present climate, the reflection of solar energy back to space dominates, and the net effect of clouds is to reduce the net flux of incoming energy at the top of the atmosphere (TOA) by ~20W/m*2, as compared to an otherwise identical planet without clouds. ###################################################################### There is something here for a lot of people to learn from. Admittedly I'm finding it difficult to find information to look into this. Would anyone here be able to explain how Andy came to 20W/M*2. How does the net effect of clouds reduce the net flux of incoming energy at the top of the atmosphere by 20w/m*2, as compared to an otherwise identical planet without clouds?
  34. The 2nd law of thermodynamics and the greenhouse effect
    This discussion would manage a great deal less misinterpretation if using an agreed text book on thermodynamics which includes the rigorous mathematical development. Then can be on "same page" as it were. What is you suggested reference damorbel?
  35. Extreme weather isn't caused by global warming
    From 2010 - Global temperature and Europe's Frigid Air: We live in a world of contrasts gone wild. In producing this map the radius of influence of a given station is limited to 250 km to allow extreme temperature anomalies to be apparent. Northern Europe had negative anomalies of more than 4°C, while the Hudson Bay region of Canada had monthly mean anomalies greater than +10°C.
  36. An Even Cloudier Outlook for Low Climate Sensitivity
    MarkR, thanks for pointing out the broken link. Hopefully this will work http://gmao.gsfc.nasa.gov/pubs/docs/Rienecker369.pdf otherwise cut and paste http://gmao.gsfc.nasa.gov/pubs/docs/Rienecker369.pdf into your browser. This technical report is really quite good and it does list what observation data is assimilated into the model. It does not appear to include SAR data or any other terrestrial data, I assume it was created specifically for satellite data assimilation.
  37. The Scientific Guide to Global Warming Skepticism
    #41: The map in that page is stunning and well worth showing, but I will put it in the 'extreme weather' thread.
  38. The 2nd law of thermodynamics and the greenhouse effect
    Re #162 Riccardo you wrote :- "honestly I find it and the discussion on the caloric theory really pedantic." Um, well, yes; very interesting. Tell me do you also reject the conclusions that have been drawn in consequence of the failure of the 'caloric theory' to match scientific observations, such as the 1st law of thermodynamics, the conservation of energy etc.? You wrote also :- "You confuse heat and internal energy. Here's the first quote I found just googling, but I urge you to check in a standard textbook:" In #160 I was drawing a distinction between internal energy which causes a temperature change (heat) and internal energy that doesn't cause a temperature change, sometime (mistakenly) called 'latent' heat. How do you draw a distiction between the two? I have seen the sort of 'stuff' in the link you give and I often wonder how the idea came about. Of course latent heat is not the only manifestation of the inadequacy of the definition in your link. What about gases with different specific heats? Equal molar quantities of He, O2 and CO2 at the same temperature possess completely different amounts of thermal energy, can you say what their temperatures would be if they had the same (molar) internal energy?
  39. How climate skeptics mislead
    > I'll never believe a word based solely on the fact it > appeared in a peer reviewed paper Wise; that's only the beginning; then look for citing papers and followup work, which always come along if the idea is interesting > until I understand it properly What if you can't? Are you as smart and well educated as _every_ publishing scientist in every field? > and I think you'd better do the same "... everybody was finally equal. They weren't only equal before God and the law. They were equal every which way. Nobody was smarter than anybody else. ...." http://www.tnellen.com/cybereng/harrison.html
  40. The Scientific Guide to Global Warming Skepticism
    NASA GISS has a new page about the record high November global temperature and cold weather anomaly in Europe. 2010 - Global Temperature and Europe's Frigid Air
    Moderator Response: Fixed broken link
  41. An Even Cloudier Outlook for Low Climate Sensitivity
    Eric, your first link is broken! I'm not familiar with data used here, but ECMWF reanalyses are extensively validated and generally speaking the use of AGCMs isn't a problem since the sets feature regular data assimilation which prevents drift and includes the effect of coupled changes. If you have the time to delve further then I'm sure there will be plenty of papers discussing validation and testing. There are some problems with certain sets (e.g. ERA40 snow mass) but in that case at least the reasons are well known and publicised. I'm not sure what you mean by no observations of wind: iirc synthetic aperture radar observations are regularly assimilated and they can give good estimates for wind speed over oceans...
  42. Stratospheric Cooling and Tropospheric Warming
    Guten Tag Ebel, aber, mein Deutch ist nicht sehr gut. :-)
  43. Stratospheric Cooling and Tropospheric Warming
    Mars, Joe, and TallGuy, The environmental lapse rate is not the same as the adiabatic lapse rate. There are other factors at work; one of them is the loss of energy through radiation. My take is that stratospheric cooling has two components: less radiation getting out from the troposphere and greater ability to radiate LW. The less radiation leaving bit is only until a new, higher point of equilibrium is reached. One thing I'd like to mention is that the leveling off to a new equilibrium temperature will not even start until after CO2 levels are stabilized. The leveling off of CO2 is not guaranteed to remain within our ability to affect depending on how the feedbacks play out.
  44. It's not us
    #10: "located at the upper reaches of the troposphere." That seems unlikely as the increasing concentrations are measured at surface stations with a wide variety of elevations, notably Mauna Loa at 3400 m. But it would be helpful to know where you read that, because I've seen everything from 'they are well-mixed' to 'they are at highest concentrations near the surface'.
  45. The 2nd law of thermodynamics and the greenhouse effect
    damorbel "So first off heat doesn't flow'; only fluids flow" honestly I find it and the discussion on the caloric theory really pedantic. You confuse heat and internal energy. Here's the first quote I found just googling, but I urge you to check in a standard textbook:
    "Heat may be defined as energy in transit from a high temperature object to a lower temperature object. An object does not possess "heat"; the appropriate term for the microscopic energy in an object is internal energy."
  46. How do we know CO2 is causing warming?
    VTG - I disagree based on the papers listed in the articles. Taking say the Philipona/Evans approach, you MEASURE the DLR amplitude and spectrum. To compute what it "should" be (model result), then calculate from radiative transfer equations (Ramanathan and Coatley 1978 for the maths). This is a very different calculation from the demonised GCMs - no dynamic component and insensitive to minor variations so you dont need minutely accurate picture of atmosphere for clear-sky calculation. Not only does the calculation match measurement for amplitude and spectrum, but it is very hard to see how you could obtain that measurement without the CO2 greenhouse effect. Can do essentially the same at the TOA. This doesnt tell you all about surface heating but it does tell what the radiative heating due to CO2 is. To argue about AGW, you need to look at other factors and feedbacks but I'd need a convincing explanation of those measurements from another theory to doubt the radiative component of CO2.
  47. The 2nd law of thermodynamics and the greenhouse effect
    Re #160 - should have been "Re #159 Philippe Chantreau"
  48. The 2nd law of thermodynamics and the greenhouse effect
    Re #153 Philippe Chantreau you wrote:- " confused between heat (in thermodynamics, that means net heat flow) and energy (which can be almost anything). Heat must comply with the 3 laws. Energy can flow ." I hope I have a good grasp of your meaning because I do think you have a good understanding of the matter. Please do not think I am just being pedantic because all matters in thermodynamics and energy are closely related therefore words must be used with a precise meaning. So first off heat doesn't flow'; only fluids flow. This was the failure of the old caloric theory; caloric was supposed to be a fluid 'filling in the spaces' between the atoms and giving it the feeling of hotness. This theory came into question when it was realised that the friction involved in boring out a cannon barrel that caused it to get hotter; the temperature rise could be directly related to the (frictional) work done. Also hotter material weighed no more than when it was cold. At the time this was powerful evidence because Lavoisier had used a similar technique to disprove the phlogiston theory of combustion. A second, more modern, confusion; the one about heat meaning 'net heat flow'; a sort of term for energy 'in transit' (somehow). Let there be no doubt about it, heat is energy density where the energy is in the form of molecular motion, it is to be found in all materials above 0K. This energy density is the material's temperature, it is only related to energy by dividing the energy by the material's specific heat K = Q/C. As you say just saying 'energy' is far too vague, e.g. for mixtures of steam and water; water contains a lot of none-thermal energy in the binding force that make its molecules a liquid - this is the energy also called the latent heat of evaporation. But the binding force has got nothing to do with molecular motion, even though the energy it implies can only be overcome by molecular motion. In regard to this last matter, the heat of a water/steam continuum dose not increase as the % steam increases because the temperature doesn't change, only the energy in the system increases. That is why a water/steam mixture can be at equilibrium i.e. the temperature in the liquid is the same as the steam, so no energy transfer (no change in entropy).
  49. An Even Cloudier Outlook for Low Climate Sensitivity
    Maybe Dr. Dessler would be kind enough to also answer questions here? Other prominent and respected climate scientists (including Trenberth and Soden) agree that Dr. Dessler's methodology is sound. Certainly much more sound that that used by Lindzen and Choi (2009). From ClimateProgress: "This is a very important check of the models,” says climate researcher Qiang Fu of the University of Washington, Seattle. “It shows no evidence of a large negative cloud feedback.” But climate researcher Roy Spencer of the University of Alabama, Huntsville, disagrees. He published one of the two papers finding evidence of a strongly negative cloud feedback. He finds in his own analyses signs that Dessler is seeing not only cloud changes caused by temperature changes but also temperature changes caused by natural cloud fluctuations. Such effects garble the true negative feedback beyond recognition, he says. Spencer’s “interpretation is wrong," says Soden, but even if Spencer were right that there’s a cause-and-effect problem, Dessler’s method of comparing observations and models "eliminates some possibilities, such as the models being egregiously wrong. It’s about as good as we can do with current data sets." Also, "Dr. Kevin Trenberth, head of the Climate Analysis Section at the National Center for Atmospheric Research, is one of the leading experts on cloud modeling. He had been critical of some recent studies on the cloud feedback effect, so I asked for his thoughts on this study. He replied: "The work is sound and is a very useful contribution. It is a foil to some of the misleading work that Richard Lindzen has published (and which we have shown is wrong). Kudos to Andy Dessler for trying to do this and doing it as well as it can be done." Those are some pretty glowing reviews from some very critical and discerning climate scientists. Trenberth in particular, is a stickler for details, so his support of Dessler is important.
  50. Stratospheric Cooling and Tropospheric Warming
    No saturation. Es ergibt sich folgende Kurzdarstellung des Treibhauseffektes in 5 Punkten: 1. Die Atmosphäre ist im Wesentlichen zweigeteilt: unten die konvektionsreiche Troposphäre, in der das Wetter ist und wo wir leben und oben die konvektionsarme Stratotosphäre, wobei sich die Grenze zwischen beiden Sphären verschieben kann. 2. Der Temperaturgradient in der Troposphäre ist (fast) konstant - auch wenn sich die Dicke der Troposphäre ändert. Diese Konstanz ist konvektionsbedingt. 3. Die fast konstante optische Dicke einer sich ändernden Stratosphäre. Diese Konstanz ist strahlungsbedingt und ergibt sich aus der Skalierung (Maßstabsänderung) der Strahlungstransportgleichung bei Änderung der optischen Dicke bei Konzentrationsänderung des CO2. 4. Wenn der Temperaturgradient einen bestimmten Grenzwert überschreitet kann die Luftschichtung nicht ruhig bleiben und wird instabil = Konvektion = Kennzeichen der Troposphäre 5. Im stationären Zustand (d.h. auch wenn Zeit vergeht, ändert sich der Zustand nicht) ist im Mittel die Wärmeabgabe der Erde genau so groß wie die Wärmeabsorption - andernfalls müßten sich die Temperaturen laufend ändern. Das aber widerspräche der Stationarität. Diese 5 Punkte liefern eine Grundsensitivität der durchschnittlichen Oberflächentemperatur als Folge von Konzentrationsänderungen des CO2. Ergänzung: Die dickere Tropopsphäre hat eine größere Temperaturdiffernz zwischen oben und unten, wobei diese größere Temperaturdifferenz sich als Abkühlung oben und Erwärmung unten so verteilt, daß die Gesamtabstrahlung der Erde gleich der Gesamtabsorption ist. MfG

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