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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 105901 to 105950:

  1. Waste heat vs greenhouse warming
    KR #301 "...you could have done this yourself" Would you have used my formula? I doubt it. At any rate, it appears you do agree there is something going on here as you say "waste heat... might at equilibrium add 0.015°C to 0.034°C. ". Before assuming losses, why not first determine how this waste heat might raise temperature? If the volume of air is assumed, 4.2 billion cubic kilometers, according to http://wiki.answers.com/Q/What_is_the_volume_of_Earth's_atmosphere air´s heat capacity cp = 1.0 kJ/kg C, according to... http://www.engineeringtoolbox.com/air-specific-heat-capacity-d_705.html the mass of air, roughly 1.2 kg/m3 @ 15 C, according to http://ballonsolaire.pagesperso-orange.fr/en-theorie1.htm and the amount of waste heat per year is around 474 x 10E18 J according to the link you provide above,...calculating.. 4.2x10E9 km3 = 4.2x10E18 m3, whih yeilds 5x10E18 kg, multiply by cp (10E3 J/kgC), you get 5x10E21 J/C, which means it takes that much energy to raise the atmosphere temp 1 degree C. That seems like a lot of energy to me. But according to the link you provided, the amount of waste heat per year is 474 x 10E21 J. Taking this value .474x10E21 J and dividing by the amount of energy required as calculated above (5x10E21 J/C) We get 0.0948 C. Rounding up, that's 0.1 C per year. If one assumes all of this energy is lost to space, then all of global warming is likely due to GHGs. But since AGW assumes the ability of the atmosphere to radiate energy is getting worse as time goes on, it has to be assumed that some portion of this energy is not escaping, and is therefore accumulating. Assuming (just for grins) only a tenth of this energy is retained. This would yeild a .01 C increase each year. After on century you get an increase of 1 C. But 1 or 2 degrees C is roughly what GHG are supposedly adding to global temperatures over the next century in the best of circumstances, and perhaps more in the worst of circumstances, which could have also been achieved by assuming just a little more waste heat being retained. Concluding... it looks like ignoring waste heat is literally "playing with fire". But that is just a skeptic talking.
  2. Blaming global warming on the oceans - a basic rebuttal
    TTTM No you certainly didn't explain that well. You appear to be providing a circular argument - a form of logical fallacy. Remember that unlike anthropogenic climate change, logic is something that we can prove is true or false. Think about it like this: If we have a x quantity of CO2, then the amount of water vapour in the atmosphere will go up by y such that y = f(x). To the extent that the oceans exist, and they contain the largest surface area of water with which to create vapour, we can solidly assume that the oceans drive water vapour greenhouse feedback. This is not the same proposition as 'the oceans drive warming'.
  3. The 2nd law of thermodynamics and the greenhouse effect
    Tarcisio, #30. I'm sorry, I do not understand what you are trying to say. Stylo, #31. 1. your first blanket would radiate away heat, but slower than your body alone would do so because it is cooler. That's why you warm up. A second blanket would slow down the heat-loss from the first blanket for the same reason, so you would still get warmer. sure, there is a physical limit in this analogy, eventually you would die of heat-stroke and stop emitting heat. Then you and your blankets would all cool down. 3. What do you mean by 'passively warmed'? The earth is being actively warmed by the sun. Energy is being pumped into it by solar radiation. Nothing requires heat to flow from the atmosphere to the earth, we need only slow the rate of loss of heat by the earth, and it will get warmer. That's what GHGs do.
  4. Blaming global warming on the oceans - a basic rebuttal
    I dont think I explained that well. Read his statement again. Critically read it.
  5. Blaming global warming on the oceans - a basic rebuttal
    kdkd, The theory goes CO2 drives the warming of the oceans and through increased water vapour, the oceans drive the warming of the earth. Its a matter of perspective.
  6. Blaming global warming on the oceans - a basic rebuttal
    TTTM No, the water vapour content of the atmosphere is proportional to the temperature. It follows, not leads temperature. As it follows temperature it can not be driving warming.
  7. The 2nd law of thermodynamics and the greenhouse effect
    #31, Stylo: 1. On blankets: This relates to an analogy rather than physics, so I'll leave it aside. 2. "Doesn't water vapor block radiation coming from the sun? Shouldn't increased water vapor act as a negative feedback?" Yes, water vapor does block some infrared (IR) radiation at high frequencies. However, if you look at these absorption bands in the context of the two blackbody-radiation graphs, you find: - Your first graph shows the spectrum of incoming radiation from the sun. - Your second graph shows the spectra from both the incoming radiation and the outgoing radiation (from the earth, headed into space). - The water-vapor lines have taken a bit out of the solar-radiation emission spectrum (which is mostly in the visible and higher-frequency IR), but nearly wipe out about 2/3 of the earth-radiation spectrum: This can be seen in your 2nd graph. - So if you add more water vapor, you cut back on radiant input (solar) a bit, but you cut back on radiant output (into space) a lot. - Since the water vapor has a huge percentage impact on the earth-radiation spectrum but just a minor effect on the solar-radiation spectrum (and since the total power under both these graphs have to be very very nearly the same (SEE NOTE)), the overall impact of additional water vapor will be to increase the warming effect. 3. "Heat does not flow from cooler to warmer." - True, if you put a cold object in direct physical contact with a warm object, heat will be conducted only from the warmer to the cooler, not the other way. - But we are not talking about heat conduction, we are talking about radiant energy transfer. There is no 2nd-law problem with SOME radiated power from the cooler object (which still gives off radiation, remember: Power proportional to (temperature)^4 ) being absorbed by the warmer object. This doesn't violate the 2nd law because EVEN MORE power radiated from the warmer object is absorbed by the colder object. So the net transfer of heat is going to be from warmer to hotter. There is no problem with this. - Perhaps you are getting confused by the old-fashioned language of heat engines, etc. A slightly more abstract but simpler, and equivalent, approach is to think of it in terms of entropy: The 2nd law states that the entropy of the universe can only increase; so a process that would result in a decrease of entropy would violate the 2nd law. Example: Heat (dQ) flows from hot object 1 to cold object 2 (T_1 > T_2): the entropy change is: dS = (1/T_1)*(-dQ) + (1/T_2)*(dQ) = (1/T_2 - 1/T_1)*dQ = {(T_1-T_2)/(T_1*T_2)}*dQ Since T_1 > T_2, dS > 0, and this is OK by the 2nd law. But if you try having dQ be negative (heat flowing from cold object at T_2 to hot object at T_1), you will get dS < 0. WARNING! That means it's impossible. So heat conduction will ALWAYS and ONLY be from the warmer to the colder body. But now let's consider radiant transfer: Both bodies at T_1 and T_2 are radiating energy away, and absorbing whatever radiant energy falls upon them. The energy that is radiated from object 1 and absorbed by object 2 is proportional to the intensity of the radiation from object 1, I_1. Correspondingly, the energy radiated from object 2 and absorbed by object 1, in time dt, is proportional to the intensity of radiation from object 2, I_2. Since T_1 > T_2, I_1 > I_2 (Stefan-Boltzmann law). (The constants of proportionality are the same, because they are determined by geometrical considerations which are reciprocal between the two objects.) Hence, the entropy increment associated with the radiant energy flow from 1 to 2 is: dS_a = -(1/T_1)*(I_1 * dt) + (1/T_2)*(I_1 * dt) .....= {(T_1 - T_2)/(T_1*T_2)}*(I_1 * dt) Likewise, the entropy increment associated with the radiant energy flow from 2 to 1 is: dS_b = (1/T_1)*(I_2 * dt) - (1/T_2)*(I_2 * dt) .....= {(T_2 - T_1)/(T_1*T_2)}*(I_2 * dt) Now, if we look at dS_a, we see that dS_a > 0 because T_1 > T_2: no problem. But if we look at dS_b, we see that dS_b < 0. Does that mean that process b (radiant flow from object 2 to object 1) is impossible? NO, not if it is done as part & parcel with process a (and it WILL be part & parcel: as soon as radiation can go from 1 to 2, it can also go from 2 to 1): In that case, dS_total = dS_a + dS_b .........= {(T_1 - T_2)/(T_1*T_2)} * (I_1 - I_2)*dt and this is > 0, because T_1 > T_2 and I_1 > I_2. Hence, when you put processes a and b together, it's completely legitimate with regard to the 2nd-law. You might ask, "Is it legal to do that? To combine a process that would seem to be illegal alone with another so that the total is legal?" Yes, it is: Consider the Carnot cycle, run in refrigerator mode: It takes heat from a cooler object and deposits in a hotter object (horrors!). It's all legal, because the work you have to put in to make it balance ensures that the total entropy change is non-negative. That means it's fine from a 2nd-law perspective. And that's a good thing for those bottles of beer you have in your 'fridge. NOTE: Someone might wonder, "Why is the total power under the solar-radiation input curve the same as the total power under the earth-radiation output curve? Isn't the sun much hotter, and so doesn't the Stefan-Boltzman law state that the sun must be radiating much more energy?" The answer is Yes, the sun is radiating much more energy in total; but we're just receiving a fraction of it, as we are at a distance 1 AU away from the sun, and so the intensity of the radiation we receive is reduced by factor (1/distance^2). Whereas we are sitting on the earth, and get the full benefit of the blackbody emission spectrum from it. Since the earth is only warming slowly, the total influx must very nearly balance the total outflux; therefore the integrated powers have to be very nearly the same.
  8. Blaming global warming on the oceans - a basic rebuttal
    "There are no indicators of ocean heat driving temperature changes that are supported by the evidence." Did you really just say that? Water vapour feedback is considered by AGW theory to dominate the heating and that comes from the warmer oceans. Perhaps you need to rephrase what you mean to be a bit more specific?
  9. Climate cherry pickers: Falling humidity
    "And John, do you have ANY evidence at all that water wapor never acts as a forcing?" How do you get water vapour to change without something else (eg temperature rise) first causing it? The cause of the temperature rise is the forcing not the water vapour.
  10. The 2nd law of thermodynamics and the greenhouse effect
    Glenn Tamblyn, I understand your point (and ProfMandia). It's difficult to judge what should and what should not be said in a basic level explanation. If a user has no previous kowledge, the simple blanket analogy is easy enough. A blanket reduces your body heat losses, the GHGs do the same with the earth. No details, no conduction, radiation or Plank, but essentially it shows that putting something less cold than the ambient near a warm body helps keep it warm by reducing heat losses. The 2nd law is not addressed explicitly; the analogy just shows that what may seem to violate the 2nd law, in reality does not. In my view, it is an intermediate level explanation that should explicitly mention the mechanism to explain why the second law is not violated. In the end, it all depends on the audience one immagine to have when writing a post. I myself wrote a few posts here and the hardest part was answering to the question "to whom am I talking?". The problem is that there's no single answer or, better, the real answer is "to everyone".
  11. Philippe Chantreau at 19:08 PM on 24 October 2010
    The 2nd law of thermodynamics and the greenhouse effect
    Stylo exhibits the common confusion that has so succesfully been exploited in this non debate. Even G&T do the same thing: confuse heat (in the thermodynamic sense) and energy, or radiation.
  12. The 2nd law of thermodynamics and the greenhouse effect
    Riccardo @20 "it shouldn't be necessary to add "net" to heat, it is already the net energy exchange (or flux)" Of course it is, but that is when speaking to a moderatly technically literate audience. I have had sceptics tell me that down-welling longwave radiation can't exist because heat cannot radiate from a cold atmosphere to the warmer Earth's surface. This is the point, particulary with the basic posts. They have to provide information to the undecided who for example have never heard of this "Stefan Boltzman guy" (I have encountered this) in simple form without providing fodder for deliberate or ignorant mis-representation along the lines of: "I was over at this warmist site and they didn't even understand that heat can't flow from a cold source to a hot source. These people are trying to con us all with this junk science ... blah ... blah ..."
  13. Waste heat vs greenhouse warming
    @RSVP: "...electricity that in turn produces heat, which generates IR, which generates electricity.... you could call it the Perpetual Motion Heat Diode Energy Saver, patent pending." You seem to miss the point that it's "waste" heat. The amount wasted being less than the amount recycled...well, you can figure out the rest. Hopefully. "Sorry, I missed an important nuance of your idea for recycling energy, and that is you only wanted to recycle waste heat." Nowhere did I read that CBD wanted to only recycle waste heat. You're really grasping at straws, now. It seems as though you're not even trying anymore.
  14. Waste heat vs greenhouse warming
    #311 Sorry, I missed an important nuance of your idea for recycling energy, and that is you only wanted to recycle waste heat. What about all that excess heat from GHGs? Whos side are you on anyway?
  15. Waste heat vs greenhouse warming
    CBDunkerson #311 "By then we might have perfected infrared rectifying antennas and be turning 'waste heat' itself into electricity." ...electricity that in turn produces heat, which generates IR, which generates electricity.... you could call it the Perpetual Motion Heat Diode Energy Saver, patent pending.
  16. The 2nd law of thermodynamics and the greenhouse effect
    #25 ProfMandia at 08:26 AM on 24 October, 2010 "Increased GHGs keep the surface warmer due to changes in radiative transfer and a blanket keeps the body warmer by suppressing convection." Indeed the primary reason a green house is warmer is because of the suppressed convection. So the mechanism of "greenhouse" gases starts off with a basic confusion. The easiest way I've found to explain the GHG effect is to ask someone to compare a dry cloudless night with a humid cloud-covered night. Using this as the example, it isn't very hard to get across the concept of the surface radiating upward and that energy getting reflected either just a little (clear, dry night) or a lot (humid, cloudy night).
  17. The 2nd law of thermodynamics and the greenhouse effect
    1. A blanket is opaque to IR just as much as to light. If a blanket warmed by absorption and emission, rather than by blocking convection, then the first blanket -- blocking 100% of the IR radiation -- would do all the warming that could occur and a second blanket could cause no further warming (contrary to reality). 2. If greenhouse is a blanket that sends some heat back the way it came then this must be true of the radiation coming in from the sun as well as going out. Notice these two diagrams show that water vapour absorbs far more frequencies of radiation, especially incoming from the sun, than CO2. Therefore water vapour would provide a negative feedback, cooling the earth. 3. Even though there's radiation from the cooler atmosphere to the warmer ground, heat does not flow from the cooler to the warmer. An object passively warmed can't make the warming object warmer than it otherwise would be unless you believe you can get energy for free. Yet, remarkably, this fallacy is the basis of the greenhouse effect.
    Moderator Response: You should read the Intermediate version of 2nd law of thermodynamics contradicts greenhouse theory. Then read CO2 effect is weak, both the Intermediate and Advanced versions.
  18. Tarcisio José D at 14:10 PM on 24 October 2010
    The 2nd law of thermodynamics and the greenhouse effect
    TonyWildish Suponha uma antena trnsmitindo 1W e outra recebendo este sinal num ponto tal que seja induzidos 1 dBm (1mW). Divida então este 1W de sinal e aplique em 1000 antenas. Em nossa antena receptora teremos 1w de sinal. Como ? dirias e a segunda lei da termodinamica ?. No caso da atmosfera ocorre a mesma coisa. São 6.022 E23 antenas por moll de ar transmitindo IR (ondas eletromagneticas). Translated by google Kooiti Matsuda Voce está correto, mas apresentei apenas um exemplo local sem o intuito de apresentar avoles absolutos. Mostrando que o fluxo energetico que chega ao solo é maior que a energia enviada pelo sol. TonyWildish Suppose an antenna trnsmitindo 1W and the other receiving this signal at a point that is induced 1 dBm (1mW). Then divide this signal and apply 1W in 1000 antennas. In our receiving antenna will 1w signal. How? would you say and the second law of thermodynamics?. In the case of the atmosphere is the same thing. 6022 E23 St antennas for transmitting IR moll air (waves electromagnetic). Kooiti Matsuda You're right, but has just one local example without the intention of presenting absolute avola. Showing the energetic flow that reaches the ground is greater than the energy sent by the sun.
  19. The 2nd law of thermodynamics and the greenhouse effect
    Re: Kooiti Masuda (27) I pulled these references off of Barton Paul Levenson's Climatology pages (he specializes in atmospheric physics):
    Goode, Philip 1998. "Earthshine Measurements of Global Atmospheric Properties." http://www.bbso.njit.edu/Research/Earthshine/earthshine-proposal.html, accessed 10/13/1998. Houghton, J.T. 2002 (1977). The Physics of Atmospheres. Cambridge: Cambridge University Press. Lorenz, R.D. and C.P. McKay 2003. "A Simple Expression for Vertical Convective Fluxes in Planetary Atmospheres." Icarus 165, 407-413. Trenberth, K.E., J.T. Fasullo and J. Kiehl 2009. "Earth's Global Energy Budget." Bull. Amer. Meteorol. Soc., preprint.
    BPL also has an online planetary temperature calulator here. Not exactly what you may have been looking for, but I hope it helps! The Yooper
  20. The 2nd law of thermodynamics and the greenhouse effect
    I think that the blanket analogy is less troublesome than greenhouse (glass house) analogy, for a blanket is obviously different from the atmosphere. By the way, I remember some planetary scientists use "blanket effect" as a technical term distinguished from "greenhouse effect". But, I do not remember the precise context. Probably, it is "greenhouse effect" if energy comes primarily from the sun, and it is "blanket effect" if it comes from the interior of the planet (geothermal).
  21. The 2nd law of thermodynamics and the greenhouse effect
    Help please! I do not find good textbooks of thermodynamics which contain how to interpret radiative transfer as heat exchange. Some books do contain Planck's theory of blackbody radiation, but that is not enough. Even if we are content with the blackbody spectrum, we need to handle different energy flux densities from the thermal equilibrium. We also need to evaluate the effective tempearture of radiation after partial absorption.
  22. The 2nd law of thermodynamics and the greenhouse effect
    Tarcisio José D'Avila, the value 1368 W/m2 is the energy flux coming from the sun to the unit area of a plane surface perpendicular to the line between the sun and the center of the earth. To get the value of solar energy flux per unit area of the earth's surface, it should be multiplied by the cosine of the solar zenith angle (in other words, the sine of the solar elevation angle), which depends on latitude, season, and time of day. (We are sure that the global and annual average of it is 1/4). There are many textbooks, both meteorological and astronomical, to explain how to calculate it. As for a conceptual reminder, here is an introduction from NASA. http://edmall.gsfc.nasa.gov/inv99Project.Site/Pages/science-briefs/ed-stickler/ed-irradiance.html
  23. Do critics of the hockey stick realise what they're arguing for?
    @protestant: "Anyway what we know is the temperatures always fell when CO2 was high and still rising for centuries...." It didn't "always fall" - you identified a single instance of this. In any case, that question was already answered: in normal Milankovitch cycles, CO2 is a feedback mechanism - the main forcing is orbital variations, which then cause increased albedo and lower CO2 as temperatures go down. In the current situation, anthropogenic CO2 is acting as a forcing. "CO2 follows the temperature, not the otherway around." Actually, it's both. Look, it's clear your mind was already made up that AGW wasn't real when you came here. You tried to challenge the science, and when presented with evidence of how you're wrong, you start complaining about it. To people like me, who come here to learn, you're just another random Internet contrarian, repeating the same old debunked arguments.
  24. Vote for SkS in the physics.org web awards
    @protestant: Actually, it is the contrarian's arguments that require a lot of cherry-picking and ignore the overwhelming evidence supporting AGW theory. This site is about finding the truth. I encourage you to continue learning about the science and abandon your naive belief in the pseudo-science bandied about by contrarians. If you aren't interested in learning more about science, then I suggest you just go someplace else where your preconceived notions will be welcome, such as WUWT.
  25. Vote for SkS in the physics.org web awards
    Do you think, just possibly, "protestant" has missed the point of SkS? His proposition "take in account all of the evidence" seems to fly in the face of the whole web site which is devoted to examining all of the evidence AGAINST global warming. None of which, so far, stands up.
  26. The 2nd law of thermodynamics and the greenhouse effect
    Be very careful with the blanket analogy. Increased GHGs keep the surface warmer due to changes in radiative transfer and a blanket keeps the body warmer by suppressing convection. They both keep it warmer but for very different reasons. You did note this in your third to last paragraph but it may get lost in translation if somebody carries the message from here. A person, after reading this post, might tell somebody that GHGs act like a blanket to keep us warm. "What do you mean I am wrong, I read this over at Skeptical Science."
  27. Do critics of the hockey stick realise what they're arguing for?
    #110: "you are answering to every sentence and a paragraph with another link to another "rebuttal" which takes in to account only one side of the evidence" Sorry that you feel frustrated by the references to other pages on SkS. Maybe its because the folks here have already reviewed, discussed, argued over, looked at both sides and come up with rebuttals for a lot of the tired old skepticisms. If you actually read the referenced argument page, you'll see both sides get reviewed (and that's neither cherry-picking a la Goddard nor confirmation bias a la Watts). As for Kulmala, see this comment and its quote from that article.
    Moderator Response: One of the strengths of this Skeptical Science site is its division into narrow topics (notwithstanding the few exceptionally broad topics). By commenting on the appropriate thread, you not only avoid diluting other threads, you also dramatically increase the chance of people who are interested in your topic seeing your comment, because they will be looking on the appropriate thread, not the inappropriate threads. We encourage you to post short comments on the inappropriate threads on which conversations began, but only to link to your comments on the appropriate threads. You can get the HTML for the link target of your new, appropriately placed, comment by right-clicking on your new comment's date/time tag.
  28. Waste heat vs greenhouse warming
    BTW, it's definitely off-topic here but the orbiting "solar array in space" concept has another issue w/waste heat, namely how to get rid of energy lost through transmission inefficiency. Running the numbers on microwave transmission, for instance, even with a unreasonably good efficiency any useful system would have to radiate enormous quantities of heat. Structure and mechanism to deal w/that thermal problem would seem to make the physics and economics of the whole matter even more difficult, maybe intractable. Putting arrays on the moon would make the radiator mass issue moot but would seem to be pointless as the moon has the same diurnal problem as Earth but even worse, night being much longer.
  29. Do critics of the hockey stick realise what they're arguing for?
    Ok, I promise to stop off-topic now. Continue....
  30. Waste heat vs greenhouse warming
    I realize all that, CB, it's a thought experiment. Point is, it's not really science we're arguing about here, but other stuff. Money (or more particularly who gets it), lifestyle, that sort of thing. If something other than CO2 was the issue, we'd see roughly the same array of tactics employed to avoid dealing w/the obvious.
  31. Do critics of the hockey stick realise what they're arguing for?
    #106. Go tell that to Kirkby. The initial first run results are off and being published sometimes soon. Just wait and see. For example Kulmalas results are only calculations not empirical evidence. It is just so frustrating, that you are answering to every sentence and a paragraph with another link to another "rebuttal" which takes in to account only one side of the evidence while totally ignoring some very important scientific peer-reviewed results and not providing any evidence why they should be ignored. That is called cherry picking. Being skeptical doesnt mean you have to be only skeptical about the skeptics. You also have to be skeptic about your own opinions, otherwise it leads to confirmation bias. And this is the biggest problem here.
  32. Do critics of the hockey stick realise what they're arguing for?
    #106: "Kirkbys talk about his project. " Oh, that again. As I said earlier, 'it's cosmic rays ' just doesn't stand up to scrutiny. And of course, that's the more appropriate thread for such comments.
  33. Do critics of the hockey stick realise what they're arguing for?
    doug, but they explain only a fraction of the spikes. The rest remains unexplained and let me tell you we have no idea what caused them. And until we know we cannot tell we know the forcings of today, or even if climate actually needs a forcing to change. Anyway what we know is the temperatures always fell when CO2 was high and still rising for centuries.... The base tenet for CAGW is that no change occurs if no external forcing is presented. CAGW doesnt take into account the internal unforced variability in cloud cover, which may very well have caused the MWP, LIA and a part of the Modern maximum. Many CAGW-trumpetists claim strong MWP means a more sensitive climate which is simply untrue (as some true skeptics like Judith Curry argue, you REALLY should look at her blog and read the posts&discussions about climate models and sensitivity etc. She takes the uncertainities much better in to account than to the specific results overconfident SkS). If (and propably) it is caused by internal variability, then negative feedback to radiative forcing actually fits in the explanation. We already have evidence on 60 year cycles like PDO and AMO after all, which are caused by winds, which are caused by pressure changes in condensation (cloud formation, models ignore this). No reason not to believe that there are longer cycles aswell (as again, MWP points out). We also have the empirical evidence (Spencer 2007) that more water wapor means more tropospheric clouds (cooling effect) and less stratospheric ice clouds (warming effect). We also have evidence presented by Spencer 2008 and 2010 that longer scale sensitivity analysis leads to a noisy, biased result.
  34. Waste heat vs greenhouse warming
    Doug #310: If we had that kind of 'limitless' energy then we would be able to put massive solar arrays in space and on the bright side of the moon... which could also provide effectively 'limitless' energy. The difference between a 'waste heat' forcing and a 'greenhouse heat' forcing is that the minute you turned off the fusion reactors the forcing would begin to decline rapidly... they would only cause warming so long as they were running. Carbon dioxide, on the other hand, would stay in the atmosphere and continue causing elevated temperatures for centuries. It's questionable whether we'd even be able to get up to 100x our current industrial production / waste heat and thus match CURRENT CO2 warming (let alone future CO2 warming). But if we somehow did find a way to generate that much energy the things we could accomplish would make it unnecessary to produce the waste heat. In any case, the hypothetical is centuries away, could not possibly be achieved with fossil fuels (there aren't enough of them) and would take place in a world with technologies radically different than current. In short, too far afield to possible predict. By then we might have perfected infrared rectifying antennas and be turning 'waste heat' itself into electricity.
  35. Vote for SkS in the physics.org web awards
    Come on 'protestant'. The physics.org website does not have any denier candidates shortlisted. Do you think this is just selection variability or that there is a scientific trend on physics.org? SkepticalScience does very well in the voting, and is head to head with Sixty Symbols.
  36. Do critics of the hockey stick realise what they're arguing for?
    Protestant, an example from the rebuttal: The dramatic spikes are the strong negative forcing from volcanic eruptions.
  37. The 2nd law of thermodynamics and the greenhouse effect
    protestant virtually all the skeptic scientists agree, just some blogger/blog commentrs don't. Definitely you're not alone :)
  38. Vote for SkS in the physics.org web awards
    Not going to vote for John Cook. I could vote him, if he just would take in account all of the evidence, not just the ones that match to his preconceived notions. At this state, this site is only skeptical on skepticism, not much on anything else.
  39. Waste heat vs greenhouse warming
    An interesting thing to consider would be, what if we'd thoroughly cracked fusion energy and were effortlessly liberating something like 3X the energy KR describes in his comment at 301, energy being finally "too cheap to meter," with demand escalating rapidly to spawn even higher levels of dumped energy? Now picture what would happen if one were to try to build a scientific case suggesting that all of that heat would only leave the planet once the planet had warmed to a new rough equilibrium temperature, that increasing demand would drive that "rest temperature" upward still further. Would any model be good enough to overcome opposition to ending the big party? For my part I've a feeling we'd be seeing a close analog to the present argument over CO2, employing many of the same objections.
  40. Do critics of the hockey stick realise what they're arguing for?
    #100: You asked for evidence for Cosmic Rays and climate correlation, there you go, a plot from Bond et al: http://img39.imageshack.us/img39/702/cosmicrays.jpg This graph was originally presented in Jaspers Kirkbys talk about his project. Here is the pdf: http://wattsupwiththat.files.wordpress.com/2009/07/kirkby_cern_slideshow09.pdf Another study: http://tinyurl.com/27l3a2c plus many others. And yes, CLOUD is an experiment on cosmic rays and cloud formation. And yes, it doesnt measure TSI. But as you might know, if there is lesser clouds on solar maximums due to cosmic rays, it means also more sunlight is being let in. #101. Again, the "rebuttal" doesnt address my argument. Surely, warming with positive feedbacks will stop at some point. But how can the system cool, without having a forcing which is STRONGER than co2+positive feedbacks? Decreasing CO2 cant be the cause of cooling since something had to cool the SST first. CO2 follows the temperature, not the otherway around. @moderators: Sorry for offtopic, but just had to answer some commenters who answered to mine. Since the main topic is sooo large it is sometimes hard to stand in just one small subtopic. Since everything is related to everything. At least at some point you should be able to debate the subject in a larger context?
    Moderator Response: The idea of ocean warming being the cause of the observed trend in CO2 is discussed on the "Is the long-term trend in CO2 caused by warming of the oceans?" SkS blog post.
  41. It's the sun
    @oxymoron: you're welcome. I knew sooner or later you'd come around to the side of reason. :-)
  42. Newcomers, Start Here
    David Wrathall mine was just a guess, you'd better ask how they evaluated temperature before giving my possible interpretation on what he (the Dutch meteorologist) did. As for commenting there, well, there are hundreds of blogs around and no one can follow them all. Dr. Wilson ended one of his comments (the very point where i didn't continue reading) with "Here endeth the first lesson."; he's not going to learn anything, anyway. And finally, each skeptic has his own view in contraddiction with others; untill there's no alternative theory it's impossible to follow them all.
  43. It's the sun
    archiesteel #721: Thanks. You've given me all the evidence I need.
  44. The science isn't settled
    Mistermack, Stating "A bit of warming isn't [bad]", is called argument by assertion. You aren't going to get very far by engaging the commenters on this site with logical fallacies.
  45. Waste heat vs greenhouse warming
    @RSVP: "What is more of a shame is the distraction from the real discussion, especially what appears to be pure provocation" So why do you keep generating such distractions? Why do you keep posting messages that basically amount to flamebaiting (an aggressive form of provocation)? "that is best ignored, although it can be difficult." Well, that is true. We should ignore your attempts at provocation, but that *is* difficult. The point is that anthropogenic waste heat represents 1% of anthropogenic greenhouse warming. No amount of snide remarks and strawman arguments from you (i.e. standing downwind from a forest fire) will change this.
  46. CO2 lags temperature
    Sentient, can you provide a link or citation for Tzedakis' paper? Can't find it, would like to take a look. BTW, mistermack might want to read sentient's post so as to get a better understanding of how tracking insolation for a single day is actually employed. Reevaluate what's "worthless," your remark versus the science.
  47. Waste heat vs greenhouse warming
    KR #301 Thanks for the answer.
  48. Waste heat vs greenhouse warming
    pbjamm #302 "It really appears to me that you are being argumentative rather than arguing." Well it's a shame it appears that way, but I am being asked to justify things that to me are fairly obvious. For instance, there are those that would just as well hang out downwind from a forest fire than upwind, or assume the plume of ash and gases from Iceland that stretched all the way to the Baltic, (now maybe it was just only Scotland, very sorry), contained no latent heat whatsoever, etc. What is more of a shame is the distraction from the real discussion, especially what appears to be pure provocation, that is best ignored, although it can be difficult.
  49. The 2nd law of thermodynamics and the greenhouse effect
    At least once I agree with SkS. This is some point where some skeptics are horribly wrong. Not including me.
  50. CO2 lags temperature
    You know, in science, there was once this thing we called the Theory of Multiple Working Hypotheses. Anathema (a formal ecclesiastical curse accompanied by excommunication) in modern climate science. So, in juxtaposition to the hypothesis of future global climate disruption from CO2, a scientist might well consider an antithesis or two in order to maintain ones objectivity. One such antithesis, which happens to be a long running debate in climate science, concerns the end Holocene. Or just how long the present interglacial will last. Looking at orbital mechanics and model results, Loutre and Berger (2003) in a landmark paper (meaning a widely quoted and discussed paper) for the time predicted that the current interglacial, the Holocene, might very well last another 50,000 years, particularly if CO2 were factored in. This would make the Holocene the longest lived interglacial since the onset of the Northern Hemisphere Glaciations some 2.8 million years ago. Five of the last 6 interglacials have each lasted about half of a precession cycle. The precession cycle varies from 19-23k years, and we are at the 23kyr part now, making 11,500 years half, which is also the present age of the Holocene. Which is why this discussion has relevance. But what about that 6th interglacial, the one that wasn’t on the half-precessional “clock”. That would be MIS-11 (or the Holsteinian) which according to the most recently published estimate may have lasted on the order of 20-22kyrs, with the longest estimate ranging up to 32kyrs. Loutre and Berger’s 2003 paper was soon followed by another landmark paper by Lisieki and Raymo (Oceanography, 2004), an exhaustive look at 57 globally distributed deep Ocean Drilling Project (and other) cores, which stated: “Recent research has focused on MIS 11 as a possible analog for the present interglacial [e.g., Loutre and Berger, 2003; EPICA community members, 2004] because both occur during times of low eccentricity. The LR04 age model establishes that MIS 11 spans two precession cycles, with 18O values below 3.6o/oo for 20 kyr, from 398-418 ka. In comparison, stages 9 and 5 remained below 3.6o/oo for 13 and 12 kyr, respectively, and the Holocene interglacial has lasted 11 kyr so far. In the LR04 age model, the average LSR of 29 sites is the same from 398-418 ka as from 250-650 ka; consequently, stage 11 is unlikely to be artificially stretched. However, the June 21 insolation minimum at 65N during MIS 11 is only 489 W/m2, much less pronounced than the present minimum of 474 W/m2. In addition, current insolation values are not predicted to return to the high values of late MIS 11 for another 65 kyr. We propose that this effectively precludes a ‘double precession-cycle’ interglacial [e.g., Raymo, 1997] in the Holocene without human influence.” To bring this discussion up to date, Tzedakis, in perhaps the most open peer review process currently being practised in the world today (The European Geosciences Union website Climate of the Past Discussions) published a quite thorough examination of the state of the science related to the two most recent interglacials, which like the present one, the Holocene (or MIS-1) is compared to MIS-19 and MIS-11. The other two interglacials which have occurred since the Mid Pleistocene Transition (MPT) also occurred at eccentricity minimums. Since its initial publication in 2009, and its republication after the open online peer review process again in march of this year, this paper is now also considered a landmark review of the state of paleoclimate science. In it he also considers Ruddiman’s Early Anthropogenic Hypothesis, with Rudddiman a part of the online review. Tzedakis’ concluding remarks are enlightening: “On balance, what emerges is that projections on the natural duration of the current interglacial depend on the choice of analogue, while corroboration or refutation of the “early anthropogenic hypothesis” on the basis of comparisons with earlier interglacials remains irritatingly inconclusive.” As we move further towards the construction of the antithetic argument, we will take a closer look at the post-MPT end interglacials and the last glacial for some clues. An astute reader might have gleaned that even on things which have happened, the science is not that particularly well settled. Which makes consideration of the science being settled on things which have not yet happened dubious at best. Higher resolution proxy studies from many parts of the planet suggest that the end interglacials may be quite the wild climate ride from the perspective of global climate disruption. Boettger, et al (Quaternary International 207 [2009] 137–144) abstract it: “In terrestrial records from Central and Eastern Europe the end of the Last Interglacial seems to be characterized by evident climatic and environmental instabilities recorded by geochemical and vegetation indicators. The transition (MIS 5e/5d) from the Last Interglacial (Eemian, Mikulino) to the Early Last Glacial (Early Weichselian, Early Valdai) is marked by at least two warming events as observed in geochemical data on the lake sediment profiles of Central (Gro¨bern, Neumark–Nord, Klinge) and of Eastern Europe (Ples). Results of palynological studies of all these sequences indicate simultaneously a strong increase of environmental oscillations during the very end of the Last Interglacial and the beginning of the Last Glaciation. This paper discusses possible correlations of these events between regions in Central and Eastern Europe. The pronounced climate and environment instability during the interglacial/glacial transition could be consistent with the assumption that it is about a natural phenomenon, characteristic for transitional stages. Taking into consideration that currently observed ‘‘human-induced’’ global warming coincides with the natural trend to cooling, the study of such transitional stages is important for understanding the underlying processes of the climate changes.” Hearty and Neumann (Quaternary Science Reviews 20 [2001] 1881–1895) abstracting their work in the Bahamas state: “The geology ofthe Last Interglaciation (sensu stricto, marine isotope substage (MIS) 5e) in the Bahamas records the nature of sea level and climate change. After a period of quasi-stability for most of the interglaciation, during which reefs grew to +2.5 m, sea level rose rapidly at the end ofthe period, incising notches in older limestone. After briefstillstands at +6 and perhaps +8.5 m, sea level fell with apparent speed to the MIS 5d lowstand and much cooler climatic conditions. It was during this regression from the MIS 5e highstand that the North Atlantic suffered an oceanographic ‘‘reorganization’’ about 11873 ka ago. During this same interval, massive dune-building greatly enlarged the Bahama Islands. Giant waves reshaped exposed lowlands into chevron-shaped beach ridges, ran up on older coastal ridges, and also broke off and threw megaboulders onto and over 20 m-high cliffs. The oolitic rocks recording these features yield concordant whole-rock amino acid ratios across the archipelago. Whether or not the Last Interglaciation serves as an appropriate analog for our ‘‘greenhouse’’ world, it nonetheless reveals the intricate details ofclimatic transitions between warm interglaciations and near glacial conditions.” The picture which emerges is that the post-MPT end interglacials appear to be populated with dramatic, abrupt global climate disruptions which appear to have occurred on decadal to centennial time scales. Given that the Holocene, one of at least 3 post-MPT “extreme” interglacials, may not be immune to this repetitive phenomena, and as it is half a precession cycle old now, and perhaps unlikely to grow that much older, this could very well be the natural climate “noise” from which we must discern our anthropogenic “signal” from. If we take a stroll between this interglacial and the last one back, the Eemian, we find in the Greenland ice cores that there were 24 Dansgaard-Oeschger oscillations, or abrupt warmings that occurred from just a few years to mere decades that average between 8-10C rises (D-O 19 scored 16C). The nominal difference between earth’s cold (glacial) and warm (interglacial) states being on the order of 20C. D-O events average 1470 years, the range being 1-4kyrs. Sole, Turiel and Llebot writing in Physics Letters A (366 [2007] 184–189) identified three classes of D-O oscillations in the Greenland GISP2 ice cores A (brief), B (medium) and C (long), reflecting the speed at which the warming relaxes back to the cold glacial state: “In this work ice-core CO2 time evolution in the period going from 20 to 60 kyr BP [15] has been qualitatively compared to our temperature cycles, according to the class they belong to. It can be observed in Fig. 6 that class A cycles are completely unrelated to changes in CO2 concentration. We have observed some correlation between B and C cycles and CO2 concentration, but of the opposite sign to the one expected: maxima in atmospheric CO2 concentration tend to correspond to the middle part or the end the cooling period. The role of CO2 in the oscillation phenomena seems to be more related to extend the duration of the cooling phase than to trigger warming. This could explain why cycles not coincident in time with maxima of CO2 (A cycles) rapidly decay back to the cold state. ” “Nor CO2 concentration either the astronomical cycle change the way in which the warming phase takes place. The coincidence in this phase is strong among all the characterised cycles; also, we have been able to recognise the presence of a similar warming phase in the early stages of the transition from glacial to interglacial age. Our analysis of the warming phase seems to indicate a universal triggering mechanism, what has been related with the possible existence of stochastic resonance [1,13, 21]. It has also been argued that a possible cause for the repetitive sequence of D/O events could be found in the change in the thermohaline Atlantic circulation [2,8,22,25]. However, a cause for this regular arrangement of cycles, together with a justification on the abruptness of the warming phase, is still absent in the scientific literature.” In their work, at least 13 of the 24 D-O oscillations (indeed other workers suggest the same for them all), CO2 was not the agent provocateur of the warmings but served to ameliorate the relaxation back to the cold glacial state, something which might have import whenever we finally do reach the end Holocene. Instead of triggering the abrupt warmings it appears to function as somewhat of a climate “security blanket”, if you will. Therefore in constructing the antithesis, and taking into consideration the precautionary principle, we are left to ponder if reducing CO2’s concentration in the late Holocene atmosphere might actually be the wrong thing to do.
    Moderator Response: Your comment likely will spark discussion that belongs on the thread We’re heading into an ice age. So will you please copy it into a comment on that thread? Then post a new comment on this thread, simply pointing to your comment's new home. When you have done that, I'll delete this original comment from this thread. Thanks.

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