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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 102551 to 102600:

  1. Stratospheric Cooling and Tropospheric Warming
    Re #96 Bob Guercio you wrote:- ".layer of the earth's atmosphere located above the troposphere and below the mesosphere." That's a rather broad definition, don't you think? A bit like beauty, in the eye of the beholder! Surely the UV absorption, the temperature inversion and the lack of convection are all relevant matters when considering the thermal properties of the stratosphere?
  2. A basic overview of Antarctic ice
    Daniel Bailey at 10:44 AM on 1 December, 2010 Do you not understand? "The point of the post is that focusing on Antarctic Sea Ice (ASI) is a strawman argument. ASI offers little contribution to the global energy budget, unlike changes in Arctic Sea Ice cover. Which then melts away come Antarctic summer." The problem as I see it is the anomaly for sea ice in the southern hemisphere is positive (more sea ice) and that is the case for all seasons. The antarctic sea ice expands and contracts just like the arctic sea ice does. This argument seems to speculate that when and if antarctic sea ice does melt totally in the summer continued loss of arctic sea ice will become more important as it continues to melt closer to the pole. But that doesn't seem too likely since antarctic sea ice is expanding rather than contracting and in the mean time the ice at both poles seasonally expand and contract, providing whatever effects that shrinking and expanding sea ice provides. So once again we are not talking science or real ice loss. The above argument argues that arctic sea ice will become more important than antarctic sea ice as the crystal ball is being read. One would expect that if the crystal ball were correct it would be more consistent with the theory that both poles were losing sea ice. But that is the nature of complex systems; simple explanations seldom suffice.
  3. 2nd law of thermodynamics contradicts greenhouse theory
    Re #275 Ned you cite my post:- "Highly reflective materials (high albedo) heat up slowly and cool down slowly in the absence of input; an example of this is a thermos flask with its highly polished surfaces." Then you write:- "Look, this is just wrong. It really is." So thermos (vacuum) flasks don't work this way? Care to explain how they do?
  4. 2nd law of thermodynamics contradicts greenhouse theory
    Re #273 CBDunkerson you write:- "Object A reflects 90 units and absorbs 10. That 10 absorption heats up the object until it is emitting 10 units. At that point the 90 units reflected + 10 units emitted equals the 100 units incoming and the object is at equilibrium. Object B reflects 25 units and absorbs 75. That 75 absorption heats up the object until it is emitting 75 units. At that point the 25 units reflected + 75 units emitted equals the 100 units incoming and the object is at equilibrium." Fair enough. But then you write:- "At equilibrium object A is emitting 10 units of energy and object B is emitting 75 units. Object B is thus much hotter than object A. Albedo has a direct and obvious impact on temperature." How so? A has only 10% absorption capacity, B has 75%. Now the absorption capacity is always equal to the emission capacity, after all the reflection part cannot emit as well as reflect, can it? So both objects have the same temperature, any difference would clearly break the 2nd Law of thermodynamics.
  5. Stratospheric Cooling and Tropospheric Warming
    Re my last comment. Actually your example @94 was roughly correct, but I was forgetting that most of the energy would be reflected/emitted back to space through the transparent atmosphere. A small amount of energy would warm up the atmosphere via conduction. Probably only close to the surface though.
  6. We're heading into an ice age
    #145: "it takes several millennia for carbon dioxide to get enclosed in Antarctic ice." How is that physically possible? "On average, the transformation of névé into glacial ice may take 25 to 100 years." Once the ice is fully frozen, why would there be any further aging of the air? How credible are these reported age discrepancies between ice age and air age?
  7. Stratospheric Cooling and Tropospheric Warming
    Tom Curtis@94 Actually thinking about it, if the atmosphere was 'transparent' to electromagnetic radiation but the surface wasn't, then the electromagnetic radiation reflected and emitted by the planets surface would go straight back out to space! Basically it would be similar to the Moon, but with a small amount of energy heating the atmosphere via conduction. So, yes my example was wrong, but so is your account. Goodness, I was really wondering where all the energy was going. But your fictitious model still obeys some basic laws.
  8. Renewable Baseload Energy
    Peter Lang first posted on this thread on post 177. Since that time he has made fully one third of the posts and the remainder of the posts are replies to him. He previously hijacked the "what should we do about renewable energy" thread in a similar fashion. His posts contain many false and misleading assertions. He does not treat others with respect. His posts on other blogs have been linked and shown to be strawmen and trolling. Can anything be done about this type of behaviour? I found this thread useful and enjoyed it (without posting anything myself) until post 177.
  9. The human fingerprint in the seasons
    Hi HR, Re @26&28, "I guess a definition of a 'human fingerprint' would help". I think this is why we are speaking past each other HR, because we have different understandings of what is meant by "finger print". If I recall correctly Santer et al. coined the term "fingerprint" and have applied it to the increase in the height of the tropopause. So your objection would probably apply tho that work too? HR "The problem I have is that those two options aren't the only possibilities." Could you please elaborate or present a conceptual model (preferably with links to reputable sources) which explains the observed pattern (both spatially and in the vertical) and magnitude of the observed long-term warming trend? Braganza designed an experiment which excludes solar and volcanoes. Tom's excellent post @39 leaves you even fewer options, if any at all.
  10. Stratospheric Cooling and Tropospheric Warming
    Bob Guercio at 00:47 At what what wave lengths is the increased emission from? As i and others have stated, CO2 & H2O are both net emitters in the stratosphere(2:1), where as O3 is a net absorber(9-10 micron). So to examine this we need a little more detail. (the resolution in your graphs in the main article, make it hard to make out)
  11. 2nd law of thermodynamics contradicts greenhouse theory
    I suppose this discussion about the role of albedo on equilibrium temperature should be moved to the thread about albedo. Coincidentally, Rovinpiper just posted a question about exactly that, exactly there. I replied there.
  12. It's albedo
    Yes, Rovinpiper, changing the reflectivity of a body changes the number of photons it absorbs, thereby changing the amount of energy it absorbs. All the formulas you see for calculating equilibrium temperature depend on the energy that is absorbed, not the total of that energy plus the energy that was reflected. It will help if you think of the more elemental mechanisms that are involved. A body emits more radiative energy the hotter that body is. The body gets hotter if it absorbs more energy. But radiation reflected off the body does not get absorbed, and therefore does not make the body hotter. So the body does not radiate more energy in response to incoming radiation that it reflected. Reflected radiation might just as well never have existed, in regards to that body's temperature.
  13. The human fingerprint in the seasons
    Argus @27, "How come, then, a majority of this year's heat records are from the tropics? " Could you provide a source for this please? Assuming it is correct, I'm going to hazard a guess that the records this year in the tropics were most likely because of the fairly strong El Nino event.
  14. The human fingerprint in the seasons
    Thank you, CBDunkerson and Tom Curtis, for your explanations.
  15. It's albedo
    Has it been proven that the equilibrium temperature of a body in a constant EM radiation field can be altered by altering it's reflectivity (short of perfect reflectivity where equilibrium temperature must remain undefined)? Is it not necessary to demonstrate that in order to prove that albedo or aerosol-based reflectance can influence the global mean temperature?
  16. The human fingerprint in the seasons
    In recent decades, could the upward trend in the arctic oscillation index be the cause of enhanced winter warming in the mid latitudes because a cooler stratosphere strengthens the polar vortex and the westerlies?
  17. 2nd law of thermodynamics contradicts greenhouse theory
    damorbel writes: This goes further; a planet orbiting a star is immersed in photons emitted by the Sun, the number of photons intercepted by a planet is reduced by the inverse square law but this is the only reduction, making the equilibrium temperature of a planet a function only on the Sun's (photon) temperature and the planet's distance from the Sun. The idea that planetary temperature is affected by its albedo is quite mistaken. damorbel then explains this idea further: Highly reflective materials (high albedo) heat up slowly and cool down slowly in the absence of input; an example of this is a thermos flask with its highly polished surfaces. Look, this is just wrong. It really is. If you're (understandably) reluctant to accept that from a bunch of anonymous strangers on the Internet, please just stop by whatever university is nearest to where you live and talk to someone in the physics, atmospheric science, astronomy, or earth science departments, and see if they can explain it to you. The earth receives short-wavelength radiation from the sun, and radiates away long-wavelength radiation. If the albedo of the earth increased, it will receive less short-wavelength radiation (visible, near-infrared). But this doesn't imply an immediate, corresponding reduction in outgoing long-wavelength radiation. Instead, the planet will gradually cool. As it cools, the flux of outgoing long-wavelength radiation will gradually decrease, in accordance with Stefan-Bolzmann, until incoming and outcoming radiation fluxes are once again in equilibrium, with the planet at a lower temperature.
  18. The human fingerprint in the seasons
    I agree with CBDunkerson: The feedbacks will follow the forcings.
  19. The human fingerprint in the seasons
    First, let me reiterate Sphaerica's very important point that if you accept a 40-60% water vapour feedback from increases in temperature, then you are logically committed to accepting that feedback as a result of the approx 1.2 degrees C per doubling of CO2. Given that, and given the degree of warming in the 20th century, accepting a strong water vapour feedback commits you to CO2 being the main driver of that warming. Second, if the watervapour feedback was a consequence of solar heating, it would not exhibit the same pattern as that resulting from greenhouse warming. In particular, direct solar heating would make days hotter than night, summers hotter than winter, and tropics hotter than the poles, while to a first approximation, the water vapour feedback would have the reverse effect. Because the initial forcing and feedback have effects opposite in sign, they would cancel each other out (to a first approximation), thus resulting in no signal. In contrast, a water vapour feedback to a green house forcing would reinforce the signal, consistent with the strong signal observed. Third, all though a water vapour feedback is identical to a first approximation, more detailed analysis reveals important differences. In particular, direct solar heating would result in a significant increase in humidity in the tropics, but not the poles. So the water vapour feedback induced from solar warming would also be stronger in the tropics than at the poles. In contrast, water vapour feedback from greenhouse forcing would be more evenly distributed, tending to reinforce the signal. So, stronger warming in the poles than tropics is a clear signal of an initial greenhouse forcing, irrespective of the additional signal from water vapour. Fourth, water vapour is largely confined to the troposphere, so the water vapour feedback will not result in stratospheric cooling. Consequently, for a solar forcing we would expect a warming stratosphere, and this signal would not be masked by a water vapour feedback. From a greenhouse forcing, we would expect a cooling stratosphere, with the signal not reinforced by water vapour feedback. The cooling stratosphere is the death knell to any theory that solar radiation has driven the twentieth century warming. Similar considerations show that the warming is not due to a reduction in aerosol albedo, nor due to a reduction in cloud albedo, nor due to variations in ocean heat content (ENSO, PDO, AMO).
  20. Stratospheric Cooling and Tropospheric Warming
    I don't know but I'll give it a swag based upon the definitions below which I ran across on the web. Note that there seems to be many definitions and I didn't explicity see the one that I am guessing at. Maybe it depends upon which layer you are talking about regardless of the chemistry or any other characteristic. Apparently atmospheres on all planets are layered and perhaps the first layer is the troposphere, second the stratosphere, third the mesosphere and fouth the thermosphere. By the way, a swag is a highly technical term. It means sophisticated wild ass guess. Bob Definitions .layer of the earth's atmosphere located above the troposphere and below the mesosphere. Definitions of mesosphere on the Web: •the atmospheric layer between the stratosphere and the thermosphere
  21. 2nd law of thermodynamics contradicts greenhouse theory
    damorbel, the law about equilibrium temperature uses only the energy that the object actually absorbs. Energy contained in photons that reflect off the object is excluded by that law. Think about it: Energy that the object did not absorb does not exist inside the object, and so cannot be emitted by the object. The object does not "need" to emit energy it never absorbed.
  22. We're heading into an ice age
    Looking at the graph of temperature in the past 420,000 years, one thing that strikes me is that although the current interglacial period appears as though it may be lengthier than some previous ones, it doesn't appear to have reached the same peak value as some of the previous one's, actually falling significantly short (at present). Of course 5 datasets isn't much to go on, and the earth has been around for many million years, not just 420,000 years. But who am I to argue?
  23. Renewable Baseload Energy
    Ned - well put. I've frequently expressed my opinion that increasing nuclear will be part of the forward energy mix. I suspect breeder reactors of some type (including thorium cycle) will be needed. But treating this issue as an Either/Or proposition, ignoring valid and honestly asked questions, pooh-poohing renewable data sources while using nuclear sources uncritically, and denigrating and insulting those you disagree with, well - that doesn't add to the discussion, or to my willingness to put up with such nonsense. Peter Lang - You've made some good points about relative costs. You've made some bad ones about site distribution of renewables and the backup load requirements of uncorrelated sites (if sufficiently uncorrelated sites are available in Australia, which I regard as an open question in the absence of a decent wind/solar survey). I just wish you would drop the arrogance. And actually add to the discussion with what information you have.
  24. Stratospheric Cooling and Tropospheric Warming
    Bob Guercio @93, I understood the stratosphere to be a region of the atmosphere characterised by an inverted lapse rate (it gets hotter with greater altitude) in which convection played almost no role in heat transfer, allowing strata of distinct temperatures to form. Based on the lapse rates observed on Venus, there is no such region on Venus. On the other hand, the article you link to, and several others I found by googling "Venus" "stratosphere" do in fact refer to Venus' stratosphere. So, are you and they using a different definition to mine, or am I missing something?
  25. The human fingerprint in the seasons
    Sphaerica #36 I think you spotted one more conflicting contrarian argument. And of course the "it´s the sun" reasoning lacks one key fact: sun´s irradiance has not been increasing for several decades, now. On the other hand, the increasing direct CO2 forcing can be calculated with established, century-old science.
  26. Berényi Péter at 01:37 AM on 4 December 2010
    We're heading into an ice age
    #143 Daniel Bailey at 00:14 AM on 4 December, 2010 Changes in CO2 and temps in the paleo record occurred much more slowly than what we are physically measuring today. We do not know that. At least the ice core record does not tell us anything about the swiftness of past changes. Or do you have other, undisclosed data sources to support your valiant claim? Here is the Historical CO2 Record from the Vostok Ice Core. As you can see the difference between Age of ice and Mean age of air in it is anywhere between 1879 and 6653 years (at depth 506.4 m and 3119.51 m respectively). Therefore it takes several millennia for carbon dioxide to get enclosed in Antarctic ice. With such a heavy smoothing the present spike or anything comparable to it is rendered invisible. In general it is a grave error to conclude from the fact you can't see an invisible thing that it does not exist either.
  27. 2nd law of thermodynamics contradicts greenhouse theory
    damorbel, I understand what you believe. I also know it is false. How you can not know it is false is a great mystery to me. If you fire identical lasers at a black iron plate and a mirror the black iron plate is going to get hotter than the mirror... no matter how long you wait. This is basic and obvious, because the mirror reflects more of the laser light and thus absorbs less energy than the black iron plate. Less incoming absorbed energy means a lower temperature at which the emitted radiation equals the incoming radiation (i.e. equilibrium point). The same is true of sunlight or any other radiation and any other matter it is striking. The lower the energy absorption rate the lower the final temperature of the object will be. Again, let's look at it mathematically; Incoming radiation: 100 units Object A reflectivity: 90% Object B reflectivity: 25% Object A reflects 90 units and absorbs 10. That 10 absorption heats up the object until it is emitting 10 units. At that point the 90 units reflected + 10 units emitted equals the 100 units incoming and the object is at equilibrium. Object B reflects 25 units and absorbs 75. That 75 absorption heats up the object until it is emitting 75 units. At that point the 25 units reflected + 75 units emitted equals the 100 units incoming and the object is at equilibrium. At equilibrium object A is emitting 10 units of energy and object B is emitting 75 units. Object B is thus much hotter than object A. Albedo has a direct and obvious impact on temperature.
  28. The human fingerprint in the seasons
    John, can you show what the summer's max temps are doing? What is the trend of the hottest days of the year? What is the prediction of AGW theory about the number of extreme hot days in the summer?
  29. Stratospheric Cooling and Tropospheric Warming
    The Ville @88, my understanding is that if the atmosphere were entirely transparent to radiation, all energy flows from or to it would take place at the surface. Therefore, it would warm until the energy flows from the surface to the lowermost layer of the atmosphere equalled the energy flows from that layer to the surface. That should be when the surface and the lower most layer have the same temperature. The rest of the atmosphere would derive its heat from the lowest layer, primarily by convection. That convection would establish the temperature profile at the adiabatic lapse rate. Hot air rising would still cool as it expands from reduced pressure, ensuring that the upper atmosphere (excluding the thermosphere) remained cooler than the lower atmosphere at all times. (The situation is a little more complex if we include heat transfer to the poles.) Even if a hot air parcel rose to the top of the atmosphere at a temperature above that defined by the lapse rate, it would prevent more heat transfers to the upper atmosphere by convection at its location, and gradually cool back to the adiabat by conduction and turbulent eddies. If such hot parcels of air were generated frequently enough, and cooled slowly enough, then the lapse rate could be less than the adiabat; except that even in this case it would be defined by the adiabat for periods of peak surface temperature. Again, please correct me where I am wrong.
  30. 2nd law of thermodynamics contradicts greenhouse theory
    Re #270 CBDunkerson you wrote:- "If albedo is irrelevant to temperature... why exactly is it that black asphalt gets hotter than white cement on sunny days? " You must not confuse 'rate of heating' with 'final temperature'. Highly absorptive materials heat up quickly because they absorb a large % of the incoming radiation. Switch the radiation off and they cool correspondingly quickly. Highly reflective materials (high albedo) heat up slowly and cool down slowly in the absence of input; an example of this is a thermos flask with its highly polished surfaces. In either case, black or shiny, the final temperature, after stabilisation from whatever the initial temperature was, will be the average of the fluctuating sunshine or whatever thermal input there is. You must see from this that, with a fluctuating radiation input, the temperature of the asphalt will fluctuate about the average temperature far more than the contents of the flask but both will have the same average temperature.
  31. The human fingerprint in the seasons
    I have to agree with HumanityRules' logic that any warming will increase water vapor, providing a strong, positive H2O GHG feedback in all cases, for all forcings which will give any warming of any sort a GHG signature. For this reason, it is difficult to apply the argument made by this post. Of course, to accept this logic, one must also accept net positive feedbacks and a higher climate sensitivity. You can't argue for this, and also argue that clouds will cause a negative feedback that will hold temperatures (and therefore H2O content) relatively constant. You also can't argue the line that atmospheric H2O content simply won't change with warming. But the correct statement should be that "solar forcing without any positive GHG feedbacks" would warm days more than nights and summers more than winters. This is of course a purely abstract statement, since any warming will introduce a positive H2O GHG feedback, and eventually a positive CO2 GHG feedback as well. It would also, I think, warm the troposphere but not the stratosphere (since the warming would not necessarily increase H2O content in the stratosphere, although that's now a "known question mark", as highlighted by Solomon 2010). But it is still a difference between CO2 and solar warming, in that CO2 will reach and actively cool the stratosphere (at least until solar warming introduces its own carbon feedbacks). So that argument stands as a distinction between CO2 and solar (or other) warming. So, in the end, one is again left with the question of what has caused the warming? AGW proponents say CO2 (which, for the record, is my stance). AGW deniers say that it is the sun, or cosmic rays, or seasonal Eurasian Leprechaun Farts, or just that we don't know, but it must be something other than CO2.
  32. The human fingerprint in the seasons
    Re: TOP (31)
    "Figure 1 shows green house warming started in 1980. Cool. "
     Why in the world would you make that conclusion? Are you just graph-mining? Or do you actually have a source for that opinion? I call a balk. The Yooper
  33. Stratospheric Cooling and Tropospheric Warming
    The Ville - 81 In addition to what you say about teaching, it sems that virtually everything in Physics depends upon ridiculously simple models. Bob
  34. The human fingerprint in the seasons
    Minor remark: The link to the data on the graph subtitles points to CRUTEM3v Northern Hemisphere, whereas the graph itself is CRUTEM3 global.
  35. It's a 1500 year cycle
    Re: cjshaker (22)
    "I think the bottom line is that climate modelers don't really understand the glacial cycle, nor how it really works."
     I have responded to this over here. The Yooper
  36. We're heading into an ice age
    Re: cjshaker This is a reply to your comment over on the 'It's a 1500 year cycle' thread: ---------------------------------------------------------------------------------------------------------- Re: cjshaker
    "I think the bottom line is that climate modelers don't really understand the glacial cycle, nor how it really works."
     And your source for that claim would be...? You may want to actually read up on models. Suggested starting points can be found here, here, here, here and here. The Yooper
  37. The human fingerprint in the seasons
    #31: "Greenhouse warming is primarily a land based effect. " Surely you would include the Arctic as a place where greenhouse warming is significant... that is the Arctic Ocean?
  38. Stratospheric Cooling and Tropospheric Warming
    Mighty Drunken - 90 In the steady state, which is what my blog was all about, there is not less IR energy reaching the stratosphere from below. The same amount of IR reaches the stratophere. However, the nature of this radiation is different. There is less in the frequency range that CO2 absorbs and more in the range that sails past the CO2 totally unaffected by it. Bob
  39. Stratospheric Cooling and Tropospheric Warming
    damorbel - 85 An editorial error on my part. I meant to say "Venus does have a stratosphere". http://adsabs.harvard.edu/abs/1983KosIs..21..205A
  40. The human fingerprint in the seasons
    Humanity Rules: "That means 40-60% of the warming trend from a doubling of CO2 comes from the water vapour feedback. 40-60% of the GHG fingerprint comes from water vapour. The water vapour effect is not specific to CO2 but is a consequence of a warming world. All things being equal, any process that warms the world is going to have this 40-60% water vapour feedback." That is a ridiculous over simplification. Insolation varies, when you reduce it, you reduce the energy. CO2 is present all the time and is a 'storage' mechanism. The two have different impacts on how they would effect water vapour production and retention. It is somewhat duplicitous to accuse John of over simplifying the issue, when you yourself make a faulty assumption.
  41. The human fingerprint in the seasons
    Figure 1 shows green house warming started in 1980. Cool. I wouldn't expect the tropics to necessarily warm as much in summer due to solar increases. After all if you look at the globe between the tropics you will see that you are dealing with predominantly water, not land. Greenhouse warming is primarily a land based effect. Oceans absorb almost all the solar radiation they receive and transport that heat via currents to other parts of the globe (very low albedo). Because oceans absorb almost all the heat they receive there is nothing re-radiated for CO2 to absorb. Heating of the air over the oceans is primarily driven by water temperature which is why the temperature record over the oceans is based on sea temperatures. Ocean heating due to solar activity extends to a depth of 50m-100m during the summer. This heat is not all available to heat the atmosphere immediately but is transported via various currents and usually northward and southward. So again, Figure 1 points to an effect possibly caused by a shift of some sort in ocean currents or the transport of heat from increased solar activity farther north. England is seeing this effect right now. Most of the big hurricane activity this fall was confined to the North Atlantic taking huge amounts of heat out of the Gulf Stream which warms England and northern Europe and makes it livable.
  42. We're heading into an ice age
    Re: cjshaker (142) From the literature I've read, the Vostok and Epica cores were sampled every 0.5 to 2 meters, depending upon the depth (I don't recall offhand the spacing intervals from Greenland cores). The final several hundred meters of the Vostok core was deemed unusable due to heat penetration upwelling from Lake Vostok lying underneath the borehole at that point. The larger sampling interval actually carries with it fewer questions about the resulting resolution, due to the spacing involved. More frequent sampling might yield more data, but the resulting data would not necessarily add anything new. Changes in CO2 and temps in the paleo record occurred much more slowly than what we are physically measuring today. The Yooper
  43. Mighty Drunken at 00:11 AM on 4 December 2010
    Stratospheric Cooling and Tropospheric Warming
    @Tom Curtis post 83 Looking at your post and some other explanations about stratospheric cooling I think your description is more accurate than the post. The dominating factor for the cooling is not less IR radiation reaching the stratosphere from below, but the increased emission by increasing CO2 concentration. The difference between fig. 2 and fig. 3 show the cooling effect from less IR coming from below can only be slight. Gavin's post at real climate does seems to suggest greater concentrations of greenhouse gases warm the atmosphere up to a certain altitude and above that they cool as the balance between absorption from the surface and emission into space changes, as convection dominates in the troposphere though you don't get to see this effect in the troposphere. My post is only my understanding and is probably wrong!
  44. Stratospheric Cooling and Tropospheric Warming
    Re: Bob Guercio You are very much correct, sir. While I am aware that pre-1970 (or so) CO2 was primarily a lag/feedback to temps, I was remiss in not taking the time to point that out in my comment above. I will add verbiage to that effect in my comment. Apologies for adding to your workload. :) The Yooper
  45. Stratospheric Cooling and Tropospheric Warming
    Tom Curtis: "To see this, consider a hypothetical planet whose atmosphere is completely transparent at all wavelengths of electromagnetic radiation. In this case, its surface temperature will be its temperature as measured from space, ie, its effective temperature. The temperature at any point in the atmosphere above the surface will be less than the effective temperature, and the temperature profile of the atmosphere will be defined by the adiabatic lapse rate up to the thermosphere. (Like Venus, see graphic in 80 above, it will have no stratosphere.)" Not quite correct. Although this is an interesting game. If the atmosphere were transparent to electromagnetic radiation, the only way of transporting energy would be by conduction and convection. The only lapse rate would be as a result of convection and you may very well have an 'inverse' lapse rate, eg. hotter at the top over time. In fact it would get hotter and hotter, because the atmosphere wouldn't be able to emit the accumulating energy to space. Transparency = no absorption or emission
  46. The human fingerprint in the seasons
    HR, I think the disconnect here is that you aren't considering the fact that feedbacks must perforce follow the same 'fingerprints' as the forcings which cause them. That is, if a solar forcing were causing increased Summer temperatures that would indeed result in a water vapor feedback effect... during the Summer. When Winter arrived and the impact of the solar forcing declined the water vapor feedback would follow suit. Ditto geography... if a solar forcing were causing accelerated equatorial warming then we would indeed see increased water vapor feedback... near the equator. Yes, there is always going to be some overlap and 'flow' of feedbacks, but they must always be most pronounced in the same conditions the forcing causing them is. The law of cause and effect still applies.
  47. Renewable Baseload Energy
    Re: Ned (315) Quality words, ably spoken and spot-on; bravo, sir! More comments such as yours are needed to help maintain the decorum and high level of discussion already found on most of this blog, but lacking to some degree on this thread. On the other thread, being of like mind with you, I reached out to Peter and attempted to find common ground with him...and was rebuffed. The Yooper
  48. The human fingerprint in the seasons
    27 Argus: "How come, then, a majority of this year's heat records are from the tropics?" Perhaps because annual events are not climate trends.
  49. 2nd law of thermodynamics contradicts greenhouse theory
    damorbel #270: "The idea that planetary temperature is affected by its albedo is quite mistaken." Your belief that you have any idea what you are talking about is quite mistaken. If albedo is irrelevant to temperature... why exactly is it that black asphalt gets hotter than white cement on sunny days? Or what magical property would be at work such that a planet with no atmosphere covered in white cement would be just as hot as an otherwise identical planet covered in black asphalt? That's the thing which gets me about nearly everything you say here... it isn't just that it is wrong, it is that any person capable of observing the world around them should know it is wrong. First you argue that a non-zero energy flow produces zero heating... now that reflection and absorption yield the same result. It's gibberish.
  50. Stratospheric Cooling and Tropospheric Warming
    Tom Curtis @83 " Therefore, I would have to conclude that stratospheric cooling with increased CO2 is primarilly due to increased efficiency at radiating away energy absorbed by ozone due to increased concentration of CO2. There would be a small additional boost due to reduced outgoing radiation of IR in the 15 micron (CO2) band; but that is ony a secondary cooling effect, and would have been a warming effect where it not for the presence of ozone in the stratosphere" vs my #79 "So are there two effects: 1) increased emission in the CO2 emissions bands increases thermal to radiative heat conversion and thereby reduces the temperature necessary to maintain overall heat balance AND 2) decreased absorption in the same spectrum because CO2 in the troposphere has already taken it out reduces the total heat input to the stratosphere " I think we are in agreement, so clearly we've both got something wrong ;-)

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