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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 102201 to 102250:

  1. Ocean acidification isn't serious
    Chris Shaker, The changes in tropical temperatures during the glacial/inter-glacials was much smaller than the global average, "probably" 1-2 degrees change. Most of the large temperature swings occurred at high latitudes and especially the Northern Hemisphere where continental ice sheets formed. This small change is temperature in the tropics is why the tropical rainforests were not greatly affected by the ice ages. Precessional changes (wobbles in the Earth's rotation) which affect the amount of solar radiation at the equator are thought to have had a greater significance. Localized coral bleaching is not a new phenomenon, however mass coral bleaching is, certainly within the last several hundred thousand years.
  2. A Cloudy Outlook for Low Climate Sensitivity
    MarkR, how does a hypothetical strong negative cloud-albedo feedback allow for the existence of glacial/interglacial cycles? Or millennial-scale climate variations such as the MWP and LIA?
  3. 2nd law of thermodynamics contradicts greenhouse theory
    damorbel & AWoL, the simple fact is that the stuff damorbel is saying is on the level of 'the earth is flat', 'the sun orbits the earth', and 'the earth is only 6000 years old'. It is completely at odds with science that has been considered established fact, based on hundreds of lines of evidence, for over a century. If you believe otherwise you are either a nutjob or a revolutionary genius. However, if you want to prove that you are a genius, and not a nutjob, ranting on the internet does not seem the most effective approach. If you think you've found some amazing and clear evidence which disproves the greenhouse effect (which mainstream science considers to have been proven by Tyndall in 1858) what you should be doing is publishing your findings in science journals. Trying to argue it out here, while the textbooks still contradict you, just leads people to the 'nutjob' conclusion.
  4. 2nd law of thermodynamics contradicts greenhouse theory
    damorbel writes: the wavelength function of Earth's albedo alone is irrelevant because it doesn't include the magnitude (wavelength independent part) of the albedo. It is the magnitude of the albedo, not the wavelength function, that governs energy transfer More anti-mathematical gibberish. AWoL, is this really the person you want to be following? "Albedo" is just the average spectral reflectance across a broad range of the spectrum. That's all that it is. Whether a particular photon is absorbed or reflected by a surface depends on the spectral reflectance of the surface at that particular photon's wavelength. It doesn't depend on the generalized average reflectance of the surface across a wide range of wavelengths (albedo).
  5. A Cloudy Outlook for Low Climate Sensitivity
    I don't really want to go off on a tangent here, but even if cloud-feedback on climate-sensitivity were low as some hope, this would only apply to the increase of temperature, but it wouldn't prevent further ocean-acidification, would it? So, from the "evil twin of climate change" point of view clouds don't really play a role. I often have the impression that ocean acidification is kept out of the limelight by "skeptics" as many of their lines of thought like cloud-feedback or geo-engineering don't help with that at all.
  6. 2nd law of thermodynamics contradicts greenhouse theory
    Re #315 Ned you wrote:- "2) AGW gets along fine with the 2nd law of thermodynamics; there's no stretching at all" The original argument for AGW is that "Earth radiates like a black body", that is how a supposed equilibrium temperature (without GHE) of 255K is calculated. It is this 'never justified assumption' (check p3 for a 'list of assumptions') that means the AGW 'science' breaks the 2nd Law of Thermodynamics. The fact that Earth manifestly is not a black body (because it has an albedo) destroys the GHE temperature calculation completely. Trying to sustain this by observations about a wavelength function do not account for the fact that the wavelength function of Earth's albedo alone is irrelevant because it doesn't include the magnitude (wavelength independent part) of the albedo. It is the magnitude of the albedo, not the wavelength function, that governs energy transfer, as explained in #317.
  7. Stratospheric Cooling and Tropospheric Warming
    #159 It doesn't matter if troposphere is colder - radiation goes both ways regardless of temperature gradient. Net heat transfer must be from hotter to colder, but not necessarily radiative.
  8. Stratospheric Cooling and Tropospheric Warming
    Bob Guercio: "Temperature depends only upon the kinetic energy of the molecules. Thus, after a collision, a molecule with no vibrational energy may now have vibrational energy and that molecule has less kinetic energy. So this diminution of kinetic energy from multiple molecules lowers the temperature. That molecule that has more vibrational energy deexcites and emits IR that may be absorbed by another deexcited molecule or it may simply fly off into space. This IR flying off into space is kinetic energy that is now lost forever from the stratosphere." Molecular vibration is kinetic energy Bob, because the molecule is moving. eg. if you have a lump of steel that is red hot, the molecules vibrate a lot, they don't fly about, except at the surface. http://en.wikipedia.org/wiki/Temperature
  9. 2nd law of thermodynamics contradicts greenhouse theory
    Re #307 Tom Dayton you wrote:- "multilayer insulation works even when its surfaces are not coated with reflective material." All material reflects, or more accurately, scatters radiation; mirror type reflection or indeed refraction, is called coherent scattering because the phase relationship of the incoming radiation is (largely) preserved. Coherent or not, scattering reduces the transmission of radiation through a given aperture (the Earth's disk?) This reduction is independent of the direction of the source. This means that, if the Sun's incoming radiation is reduced by factor called the Albedo, then the outgoing thermal radiation will be reduced by the same amount. The magnitude of the scattering function may well be subtantially independent of wavelength as with transparent materials such as water but that doesn't mean the radiation is not redirected away from absorption/emission. For example clouds (water) contribute substantially to the albedo because the droplets are very small, whereas the oceans (water) which appears dark in images of the Earth appears to make a much smaller contribution to the albedo. Liquid water (70% of Earth's surface) having a relatively smooth surface, allows sunlight to get to depths far greater than its wavelength where it gets gradually absorbed. Only a limited % of the radiation penetrating the water surface remerges because of the phenomenon of total internal reflection, an example of coherent scattering. This total internal reflection phenomenon applies equally to radiation originating (thermally) under the water surface, it means that thermal radiation is, to a certain extent, trapped there, reducing its emissivity in proportion and thus water (70% of... remember?) cannot radiate like the black body central to GH effect theory.
  10. A Cloudy Outlook for Low Climate Sensitivity
    RE: #10 David Horton = Lindzen and Spencer's position makes sense. They think that in a warmer world, clouds will change to have a larger cooling effect than they do now. This _is_ a long term solution and it leads to a lower climate sensitivity than the IPCC give. We could probably risk 1,200 ppm CO2 if their strongest hypothetical values are right.
  11. Stratospheric Cooling and Tropospheric Warming
    Bob, two suggestions, 1) If increased emissivity of the stratosphere rather than decreaased transmission of surface emissions through the tropsphere is the main cause, can this be shown graphically? eg by showing the emissions spectrum just for the stratosphere for different CO2 concentrations, at equal total power. This would show the higher emission in the CO2 bands and the corresponding lower temperature necessary to get the same total power out(ie area under the graph). It would, though, require someone to do the calcs which is way beyond me. It might be good enough to do this as a single slab for the stratosphere, just to show the principle? 2) From your link "Since power is energy per unit time, the energy content of IR radiation can be indicated by its IR spectrum which is a graph of power density as a function of frequency." I'd suggest the unit time bit here is unnecessary and confusing - we are not looking at dynamics. I think I'm starting to understand and have enjoyed the thread, but I'd suggest the final version needs a proper academic critique as we've shown just how easy it is to get it wrong.
  12. Ocean acidification isn't serious
    These seem like pretty massive and rapid climate changes to me. Indeed, they would affect any coral reefs growing around Greenland. I'm not aware there was, but if there was. Moderator: There isn't a coral rebuttal or post (yet). I didn't realize all those coral "arguments" existed.
  13. Ocean acidification isn't serious
    scaddenp: I put the sources detailing recent dramatic temperature shifts here, because we're talking about the inability of coral to deal with dramatic temperature shifts. It seemed surprising to me. Chris Shaker
  14. We're heading into an ice age
    scaddenp: I'm not suggesting it. The author of that paper was suggesting it is possible. The idea was fascinating to me. Been obsessed with reading about the ice age cycle lately. I have read Barney Oliver's analysis of the energy difference due to the Milankovich cycles. Such an elegant and sparse argument he made. Was a brilliant man. Chris Shaker
  15. Stratospheric Cooling and Tropospheric Warming
    Bob Guercio at 15:30 Temperature reduces with altitude in the troposphere, because of the reducing pressure with altitude in the troposphere. And thus the shortening of the optical pathway. This is correct. (Truth is convection moves the bulk of the energy at low/mid altitudes in the troposphere, the optical path is too long for radiation to effectively move it, but this energies escape is limited by the path length at higher altitudes in the troposphere. By adding CO2 it is raising the height that radiation can effectively escape. The warming of the lower atmosphere is a necessary result, to enable the T differential between layers to allow the transfer of energy up to this higher altitude, through convection, conduction and radiation.) The net transfer of energy from the stratosphere to the troposphere, is because the stratosphere is warmer than the upper troposphere, because it absorbs UV, but has a short optical pathway for transferring this energy once in the co2 bands... So LW energy can pass straight through it without interacting from the troposphere up, and also from higher up back down, until it is absorbed by the thicker atmosphere of the upper troposphere. And this is why i am a lil curious on the figures for the change in radiation, because by increasing CO2, not only will it radiate energy out of the stratosphere more efficiently, but it will absorb more of the radiation in transit up, that would have previously passed through. But i dont think i was correct on the increase in the 9-10 micron area. But would be curious to the exact figures. radiation dosnt care whether its being absorbed by a warmer or colder body, it will be absorbed by what it is incident on pending its "properties". Although intensity is an important consideration.
  16. A Cloudy Outlook for Low Climate Sensitivity
    @Camburn:"Statistically, and this is important unless you want to throw statistical analysis out with the wash, we have not warmed for the past 15 years." As the past decade has set temp. records, this claim rather shocked me, so I took the raw GISS data http://data.giss.nasa.gov/gistemp/tabledata/GLB.Ts.txt and did a linear regression analysis for the past 15 years. The result? The slope is 0.0250 degreeC per year, with standard deviation 0.0027. This means that with a 95% confidence, the temperature increase over the past 15 years was between 0.02 and 0.03 degreeC per year. Or, the total increase over those 15 years was between 0.30 and 0.45 degreeC, with 95% confidence. So Camburn, you are using different data? Could you share it with us?
  17. The human fingerprint in the seasons
    Patrick 027 (#99), I think you'll find we've hashed this out already. My take-away points are that H2O will yield a stratospheric cooling by restricting outbound flow, and CO2 will yield a cooling by not only restricting the outbound flow, but also enhancing the stratosphere's ability to radiate energy.
  18. The human fingerprint in the seasons
    RSVP, I'm not sure you properly understand the concept of heat capacity. You said, "...but does not "retain" any more heat than its specific heat capacity allows.", which I take to mean that you think there is a limit to how hot CO2 can get. Your own link covers a temperature range of 175K to 6000K and I'm pretty sure the range you'll find in our atmosphere is within this range. Heat capacity does not limit how much energy a substance can hold, it describes how much energy is required to raise a unit mass's temperature one degree. Tom (#96), I've another nit with something you said, "Because it is emitted at a higher altitude, it is emitted at a lower temperature,..." In time, energy in always equals energy out. The mean point of emission does rise to a higher altitude at that time, but its temperature is the same as what it used to be. You get a warming at the surface by following the lapse rate down. Although, if you mean at a time prior to some new equilibrium being reached, then you are entirely correct. Otherwise, I concur with what you said, and I take back what I said about it would be hard to tell a H2O signature from a CO2. This is mostly because I remembered that H2O concentration varies not only with altitude, but also with latitude. There is a lot less of it in high latitudes; so, I think the polar amplification would not be as much. Which leads me to a thought on Sphaerica's comment, "...you can't have a climate sensitivity with positive feedbacks that only kick in for CO2 but not for other forcings." Certainly true, but it strikes me now that feedbacks might come into play at different rates or different degrees dependent on what the driver is. For instance, with a more uniformly distributed GHG like CO2, you might expect more polar amplification than you would with a solar forcing driving up H2O first, which will be less well distributed. There are interesting things going on now with polar albedo, melting permafrost, and methane release that would be delayed with less of a polar amplification effect. Really curious if I'm on to something with this; though, it's mostly academic.
  19. Stratospheric Cooling and Tropospheric Warming
    Hi All, I think that somewhere in this thread there was talk about the stratosphere being more rarefied than the troposphere. I also think that this was used to justify why the troposphere doesn't cool. The logic was that any emitted radiation in the troposphere would get reabsorbed because of the proximity of the particles. I don't think this is correct. Radiation goes from the stratosphere to the troposphere because the stratosphere is warmer than the upper troposphere. Or did I misinterpret those remarks concerning pressure? Bob
  20. A Cloudy Outlook for Low Climate Sensitivity
    "1. Statistically, and this is important unless you want to throw statistical analysis out with the wash, we have not warmed for the past 15 years." Statistically speaking, unless you want to throw statistical analysis out with the wash, no one has died of tobacco-induced lung cancer in the last nanosecond. Therefore, smoking tobacco is safe.
  21. A Cloudy Outlook for Low Climate Sensitivity
    "On the other point, sensitivity is a function of warming from CO2, not the amount of CO2. " This is still nonsensical, Eric-the-so-called-skeptic, given your earlier post.
  22. The human fingerprint in the seasons
    Haven't had time to read the whole thread; justa adding onto 36 Sphaerica 39 Tom Curtis Actually, an increase in tropospheric H2O would tend to cool the stratosphere; it's a question of how much (H2O partially absorbs radiation from below in some bands, although not as extensively as tropospheric H2O; still, H2O is also at relatively small concentrations in the upper troposphere, and so it should be possible for H2O increase to reduce upward LW radiation at the tropopause in some of the same wavelengths that it can be absorbed in the stratosphere. Of course, if H2O increases in the stratopshere (from climate change? from CH4?), then ...) The seasonal and latitudinal fingerprints are also affected by feedbacks; in particular the surface albedo feedback. The most obvious fingerprint for greenhouse-forced warming (from well-mixed gases at least) in general is upper-atmospheric (above tropopause) cooling and the reduction in the diurnal temperature cycle absent feedbacks (regionally this can be complicated from changes in clouds and humidity and soil moisture and maybe the effect of CO2 itself on evapotranspiration?); others so far as I know require some fine points (finer-scale structures), differences) or more numerical specifications...
  23. actually thoughtful at 15:11 PM on 6 December 2010
    Renewable Baseload Energy
    Archiesteel: "Also, you don't get to determine if you are right or not. That's not the nature of a debate - otherwise everyone would be right, as no one would claim to be incorrect." I disagree with this. If someone can provide good information that is from a credible source and makes sense I would be HAPPY to say "I was WRONG!" And think I won because I now something I didn't know before. I come here to learn from the posts and the comments. The posts I learn by reading. The comments, more often then not, I learn by having to defend my statements or gently (ahem) pointing out (and proving out) the error of other posters' ways. That is the true value of someone like Peter Lang to me - I brush up on what they are saying enough to see their logical fallacies (or that they have a point). I also (post 349) learned enough to come up with my solution to climate change (as it involves electricity - only 40% of the CO2 problem). No small feat! But I would think all of us would be looking for the truth in the others words, and, if finding none, pointing that out, otherwise taking the truth and expanding it or at least claiming it as our own.
  24. A Cloudy Outlook for Low Climate Sensitivity
    Camburn, "1. Statistically, and this is important unless you want to throw statistical analysis out with the wash, we have not warmed for the past 15 years." Why do you insist on repeating the same incorrect information? Several people have now shown you that your assertion is incorrect. You are not being reasonable or discussing in good faith if you insist on repeating false statements and continuing to argue strawmen. "3. Global cloud cover seems to have shifted upwards from a long downward spiral." That may be, although the IPCC states: "In summary, while there is some consistency between ISCCP, ERBS, SAGE II and surface observations of a reduction in high cloud cover during the 1990s relative to the 1980s, there are substantial uncertainties in decadal trends in all data sets and at present there is no clear consensus on changes in total cloudiness over decadal time scales" Also, a 2007 paper found that even the ISCCP data have issues. "Here we show that trends observed in the ISCCP data are satellite viewing geometry artifacts and are not related to physical changes in the atmosphere. Our results suggest that in its current form, the ISCCP data may not be appropriate for certain long-term global studies, especially those focused on trends". Regardless of some people's wishful thinking, the planet continues to accumulate heat and warm. And if the McLean you linked us to @64, is the same discredited McLean behind this awful and debunked paper, then citing "information" from his site is not helping your credibility either Camburn.
  25. A Cloudy Outlook for Low Climate Sensitivity
    Re: Camburn (64)
    "Statistically, and this is important unless you want to throw statistical analysis out with the wash, we have not warmed for the past 15 years."
     Your ongoing focus on insignificant time periods shows you are doing so yourself. Trends in climate science require focusing on the data you have; ideally, 30 years is the accepted period for things to cease being considered weather and to be considered climate. Warming since 1975 is robust. Or are you going by those "feeling lucky" statistics again? The Yooper
  26. A Cloudy Outlook for Low Climate Sensitivity
    Phila: I feel very lucky for numerous reasons concerning climate. 1. Statistically, and this is important unless you want to throw statistical analysis out with the wash, we have not warmed for the past 15 years. 2. Prof Trenbeth talks about the missing heat. I will have to dig to find the paper that I read in the past few months concerning this. The observations at TOA are not what the models show should be happening. 3. Global cloud cover seems to have shifted upwards from a long downward spiral. This would help explain the lack of stastistical warming for the past 15 years. I don't know why it has done this, but it has. http://mclean.ch/climate/Cloud_global.htm
    Response: "Statistically... we have not warmed for the past 15 years."

    This issue is examined in detail at "Phil Jones says no global warming since 1995". The HadCRUT record shows around 93% chance of a warming trend - while this falls a shade below the 95% threshhold to be labelled statistically significant, to move from 93% chance of warming to "we have not warmed for the past 15 years" is a gross distortion.

    Statistically speaking, the NASA GISS temperature record does show significant warming since 1995. The European ECMWF reanalysis also shows a statistically significant warming trend. The HadCRUT record shows a lesser trend as it doesn't include Arctic regions where the greatest warming occurs (Simmons 2010). To claim "no statistically significant warming" is to ignore the fully body of evidence.

    Trenberth's "missing heat" is also address in detail at "Trenberth can't account for the lack of warming".
  27. A basic overview of Antarctic ice
    Bill, I have almost completed my analysis of the globals sea ice data....you are not going to like the results, it seems, with just a few months' data left to analyze that Philippe is correct.
  28. A Cloudy Outlook for Low Climate Sensitivity
    Having read this entire thread, it seems like Camburn has summed up the "skeptical" response pretty well @42: "I feel very lucky." Plenty of good science says that clouds may not make things better, and may even make things worse. But what of it? "I feel very lucky." Which is easy enough to say, when you're unlikely to suffer the worst consequences of being wrong. That's what makes the "skeptical" position morally untenable, IMO.
  29. Eric (skeptic) at 13:39 PM on 6 December 2010
    A Cloudy Outlook for Low Climate Sensitivity
    Dana, thanks for the replies. I agree that increasing CO2 is the correct input to the sensitivity calculation, not emissions, sorry for the confusion (I went on a tangent). I will read and comment at the GCR thread regarding that topic. Sensitivity has to be calculated from the response to local temperature changes since that it the only physical mechanism for such responses. For example an increase in sensitivity could come from increases in arctic WV which come from CO2 warming. A further rise in sensitivity could come from the earlier snow melt (reduced albedo) from that warming, or a cloud change or something else. The parameters and effects are all local and then integrated into local and then global averages. Thus the local effect from UV-induced weather pattern change in your example is very relevant. This is because the water vapor feedback from CO2 forcing is different (e.g. lower UV -> blocking pattern -> large areas of subsidence -> lower UT WV from a given amount of CO2 warming). When a number of local blocking effects are integrated over the planet, that changes the sensitivity for the planet.
  30. Stratospheric Cooling and Tropospheric Warming
    Tom, I changed the paragraph that you commented on as follows: "Consider now the atmosphere of our fictitious model. Nitrogen and CO2 molecules are in motion and the average speed of these molecules is related to the temperature of the stratosphere. Now imagine that CO2 molecules are injected into the atmosphere causing the concentration of CO2 to increase. These molecules will then collide with other molecules of either nitrogen or CO2 and some of the K.E. of these particles will be transferred to the CO2 resulting in excited CO2 molecules and a lowered stratospheric temperature. All entities, including atoms and molecules, prefer the unexcited state to the excited state. Therefore, these excited CO2 molecules will emit IR radiation which, in the rarefied stratosphere, will simply be radiated out of the stratosphere. The net result is a lower stratospheric temperature. This does not happen in the troposphere because, due to higher pressures and shorter distances between particles, any emitted radiation gets absorbed by another nearby CO2 molecule." Bob
  31. Stratospheric Cooling and Tropospheric Warming
    Tom, I'm changing it to reflect your second comment about energy being radiated both up and down. I'm thinking about the first comment. It would explain something that is not pertinent to the mechanism I'm talking about and would make my discussion more complicated. I'm inclined to say that it is at whatever temperature it is and we need not be concerned with how that happened. Thank you, Bob
  32. The human fingerprint in the seasons
    #94: Do I detect a goalpost shift? In #80, you claimed "any forcing which is continuous and as such elevates temperatures ... will be accompanied by strong GHG feedbacks (CO2, H2O) which will carry with them the same signature as a GHG forcing". If seasonal warming differences are such signatures (as per the point of this post), it appears they are not the same. I suppose we can debate why the signatures are different. As to cause of one warming episode vs. the other (a critical point), here is Meehl et al 2004: The late-twentieth-century warming can only be reproduced in the model if anthropogenic forcing (dominated by GHGs) is included, while the early twentieth-century warming requires the inclusion of natural forcings in the model (mostly solar). "It implies that there was no GHG component at all to warming prior to 1979," Not so. Merely that the solar forcing dominates. And that fits the idea that GHG forcings build slowly, as the forcing due GHG concentration is relative to pre-industrial concentration. Compare ln(300/280)= .07 vs. ln(380/280) = .305, a factor of more than 4 to 1.
  33. Stratospheric Cooling and Tropospheric Warming
    Joe, You're talking about mechanism 2 I think and you are saying that although there is less energy in the IR radiation entering the stratosphere, there is more CO2 to absorb it so the energy content may very well be the same. Am I correct? I don't think it works that way. You could triple the number of molecules but if the energy per molecule doesn't change, the temperature would be the same. I remember something like 1/2kT of energy per molecule for each degree of freedom. So if you have a situation with three times the molecules and you have the same temperature, you have three times the energy. After energy is absorbed by the troposphere, the absorption band of the energy is coming from a cooler black body so each molecule would take up less energy. I still don't have a good understanding how the energy absorbed by a molecule, which causes it to vibrate, gets converted Kinetic Energy. Bob
  34. A Cloudy Outlook for Low Climate Sensitivity
    muoncounter: May I suggest these as even more appropriate song lyrics But now they only block the sun, they rain and snow on everyone. So many things i would have done but clouds got in my way. I've looked at clouds from both sides now, From up and down, and still somehow It's cloud illusions I recall. I really don't know clouds at all.
  35. Greenhouse effect has been falsified
    Re: Henry justice (76)
    "It seems to me that the results may be more stunning with water vapor and we should reduce that too."
     You do realize, don't you, that to reduce the overall water content of the atmosphere you first have to reduce it's temperature? Water Vapor imbalances in the atmosphere equalize in approximately 8-9 days, and is highly dependent on the temperature of the air. Increasing concentrations of CO2 in the atmosphere are acting as a forcing, increasing the temperature of the air sufficient to also increase the humidity of the air by 4% (about the volume of Lake Erie). These increases in water vapor act as a feedback to further increase temperatures. The Yooper
  36. Greenhouse effect has been falsified
    I just looked at the CO2 candle and tube demonstration of the so called greenhouse effects of absorbing heat when the CO2 fills the tube. What is not shown and is important is the spectral sensitivity of the sensor tube. Also, I would like to see the same experiment with water vapor being pumped in. I really don't think this is much of a relevant experiment concerning what is happening in our atmosphere. It seems to me that the results may be more stunning with water vapor and we should reduce that too.
    Moderator Response: See the post "Water vapor is the most powerful greenhouse gas."
  37. actually thoughtful at 12:49 PM on 6 December 2010
    The human fingerprint in the seasons
    Phil @ 93 - I kind of liked the WV molecules with the clipboard, interviewing all the molecules bumping into them. As to solar forcing having a different footprint - I think this is true. This is what the article says, and also what muoncounter traces out a different way in 84. But your own point remains muddy. Do you expect solar forcing to have a warmer summer? That is what the data shows? Do you expect a GHG forcing to have a warmer winter? That is what the data shows. I am glad we both agree that HRs original point does not hold - that is what got me into the conversation (after I got out of jail using HR logic). I'll tell the WV molecules to put the clipboards away. They will exhibit less excitement....
  38. Stratospheric Cooling and Tropospheric Warming
    Bob Guercio at 01:23 Id be interested in the exact figures for the reduction in LW emitted (around 15micron) with the increase in CO2... because you are increasing the CO2 in the stratosphere by 260 odd percent... and i really doubt the reduction in LW would offset this... and with a quick over lay of the graphs, it seems to be increasing emission around the 9-10 micron mark(O3 band) Just with a quick play with modtran, it just seems that the radiative sign from the troposphere @ startosphere may be positive... but its just offset, by the increasing radiative losses in the stratosphere with increasing CO2... I dont have time at the moment to go hunting through the input files, this is just from overlaying graphs, so i could well be wrong...
  39. A Cloudy Outlook for Low Climate Sensitivity
    #54: "the only possible conclusion is that GCR did not exceed other factors in the last 30 years, not that GCR has no influence. It clearly has a substantial influence on clouds" Seems like a false dichotomy to me. I second archiesteel (#57); this idea that GCRs will somehow come to the rescue -- and that won't be until the next solar min if ever -- is pure moonshine. Here is the GCR graph from the reference I cited in #26. Neither the recent peak in GCRs or the prior 1997-98 peak did anything to modulate or moderate or block or unblock temperatures. We're still waiting for that 'substantial influence' to make itself known. This is starting to sound like a musical. With my apologies: And where are the clouds? There ought to be clouds. Well, maybe next year.
  40. A Cloudy Outlook for Low Climate Sensitivity
    Albatross - thanks! Eric, I disagree with your statement that GCR flux "clearly has a substantial influence on clouds". If you go back to my GCR article, I addressed this issue. A number of recent studies have demonstrated that GCRs actually appear to play a very minor role in cloud formation. Also as dhogaza noted in comment #56, sensitivity is measured as the response to increasing atmospheric CO2, not to increasing CO2 emissions. The sensitivity to a doubling of atmospheric CO2, which we are currently projected to reach (doubled from the pre-industrial level of 280 ppm) by mid-to-late century, is 2-4.5°C. This accounts for absorption of anthropogenic emissions by the biosphere. And like archiesteel, I've seen no convincing evidence that UV plays a significant role in climate sensitivity. I have seen evidence that it can influence local weather patterns, but that's a different subject, since sensitivity pertains to *global* temperature changes.
  41. Eric (skeptic) at 12:30 PM on 6 December 2010
    A Cloudy Outlook for Low Climate Sensitivity
    #57 archiesteel, there is no GCR counter to AGW in the past 30 years, but there could certainly be GCR warming in the late 20th century or possibly recent GCR-based cooling offsetting some warming. But GCR is not the story here, it is all the factors spelled out in How-we-know-the-sun-isnt-causing-global-warming.html which constantly fluctuate and add and subtract from the AGW warming. By not including them in either paleo studies or in the models that create clouds, we can't say anything about their effect on sensitivity. They can't be ignored just because they were canceled out over the past 30 years. #56 dhogaza, I should probably not have appropriated the term "modulate". Those statements were answers to two different questions. Natural "damping" of CO2 simply means that CO2 is only a forcing and will not be a positive feedback in any time scale we care about (contrary to On-temperature-and-CO2-in-the-past.html where the charts are missing the other factors that control sensitivity) On the other point, sensitivity is a function of warming from CO2, not the amount of CO2. There is no physical link from the amount of CO2 to the amount of water vapor (or any other postulated feedback parameter) except through CO2 warming. Sensitivity is not a constant although it can be averaged over time and over the earth usually by oversimplifying. A function for sensitivity could be something like delta T = CO2 warming times A where A is the amplification determined by how the weather changes both in response to the warming and how the weather changes in response to external factors (those factors are not necessarily other forcings). "A" would also include increases in water vapor.
  42. 2nd law of thermodynamics contradicts greenhouse theory
    AWoL, the claim of "weak" needs to be supported. There's very little that's "weak" about AGW. There are a few unknowns, but the basic physics is straightforward. The claim of "highly tortuous" is relative and therefore unarguable, since the reader/thinker making the claim may be unable to process the concepts involved. If so, this is hardly proof that the theory is in any way weak or flawed, and is more likely a sign that the reader/thinker needs to spend more time developing a comprehensive understanding rather than parroting those who have a more comforting but less physically consistent message. The layman will judge, as you say, but the layman will also believe in--and in fact kill in defense of--2000 year old theories that are still unsupported by any sort of evidence at all. If you're a strong believer in ethical behavior and integrity, think about what happens if you get it wrong and end up partially responsible for a great deal of suffering. As for Corbyn, I'll second Ned.
  43. 2nd law of thermodynamics contradicts greenhouse theory
    AWoL, let's see. (1) The counterarguments are perfectly straightforward. (2) AGW gets along fine with the 2nd law of thermodynamics; there's no stretching at all. (3) Piers Corbyn has a very poor predictive record, which is unsurprising given his unscientific methods. Aside from that, your comment is right on!
  44. Renewable Baseload Energy
    Rob@363: Yes, you can alter the rate of the reaction by the placement of the fuel rods.
  45. Stratospheric Cooling and Tropospheric Warming
    Bob @152:
    One mechanism involves the conversion of translational energy of motion or translational kinetic energy (KE) into Infrared radiation (IR) and the other method involves the absorption of IR energy by CO2 in the troposphere such that it is no longer available to the stratosphere.
    I don't think the first mechanism should be discusses without mentioning the source of the heat the CO2 is radiating away, ie, UV absorbed by ozone.
    Therefore, these excited CO2 molecules will emit IR radiation which in the rarefied stratosphere may simply sail off into space with the associated energy lost forever.
    In fact, approximately 50% of the energy is radiated downward and absorbed by CO2 in the troposphere. It still leaves the stratosphere, which is therefore cooled.
  46. The human fingerprint in the seasons
    RSVP @79, the effect of CO2 is to increase the altitude at which part of the outgoing IR radiation from Earth is emitted. Because it is emitted at a higher altitude, it is emitted at a lower temperature, and hence emits less energy than is emitted at the surface in the same part of the spectrum. Heat capacity has nothing to do with it. You should also note that CO2 is well mixed, while H2O is concentrated in lower altitudes. Lower altitude means warmer, and hence a lesser reduction in the outgoing IR when compared to the surface. Therefore, the GH effect of CO2 relative to water vapour is larger than we would expect simply by comparing their ability to absorb IR radiation, and their relative abundance. Finally, in your comment @75 you completely misinterpret Arrhenius' paper. In particular, you will note on Table 7 he shows an increase in temperature at all latitudes for an increase in CO2, and likewise a decrease at all latitudes with a decrease. Yes, CO2 does moderate temperature differences due to diurnal and seasonal cycles, but because of its moderation of heat flows between the Earth and space, not because of its heat capacity.
  47. 2nd law of thermodynamics contradicts greenhouse theory
    I've been following damorbel's arguments, and the counter arguments which seem weak and highly tortuous. Doesn't the complexity and stretching of the 2nd law of thermodynamics send any alarm bells ringing? Damorbel is certainly not alone and has my support and that of Claes Johnson(Prof Appl Maths,Stockholm), Alan Siddons, and Piers Corbyn, weatherman extraordinaire, latter-day Druid.In fact, he is probably the only pundit that is doing what scientists,as latter-day druids are supposed to do....making predictions that turn out to be correct.....unlike the agw believers. The layman will judge you, as he has done over millenia, by the accuracy of your predictions. Get it right and you'll be respected as gods. Get it wrong and you may be outlawed...or worse. Piers is anti-AGW, yet his predictions have been miles more accurate than the British Met Office....who have actually opted out of giving long-range forecasts.
  48. 2nd law of thermodynamics contradicts greenhouse theory
    Same here. Damorbel is clearly not interested in learning the science, but rather in pushing his own unsupported theories. When someone is consistently being shown wrong and he/she refuses to acknowledge it, then that persons is likely a troll looking for attention. I'll ingore him/her as well.
  49. A Cloudy Outlook for Low Climate Sensitivity
    @Eric: "UV and other components are more useful since UV modulates blocking and blocking modulates sensitivity." You have yet to demonstrate that it does at a significant enough degree to counter AGW. So far, you have failed to do so. As I said before, this idea that GCR are going to counter AGW seems nothing more than irrational wishful thinking. I have yet to see any evidence that leads me to think otherwise.
  50. A Cloudy Outlook for Low Climate Sensitivity
    "archiesteel, TSI is not a very useful measurement. UV and other components are more useful since UV modulates blocking and blocking modulates sensitivity. By damping I meant that about 1/2 of man's contribution of CO2 to the atmosphere is absorbed by nature." How does this affect ("modulate") sensitivity? By definition, sensitivity is related to the amount of CO2 in the atmosphere, not to the amount emitted by humans (or other sources). In other words after consumption by plant life, absorption by oceans, etc has been taken into account.

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