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Comments 51 to 65 out of 65:

51. KR at 12:08 PM on 15 July, 2015

    Moderators - Take note, there may be a sockpuppet in action. 

    Michael Fitzgerald, you are either co2isnotevil/George White, whose views on this site were shown to be nonsense years ago, or you are parroting his views without credit.

    Your last post with "..1.6 W/m^2 of surface emissions per W/m^2 of net solar input..." directly echos many co2isnotevil SkS posts both in phrasing and in claims about short climate response, and both your phrasing "...incremental solar input..."  and arguments here directly match a July 3rd 2015 co2isnotevil post at WUWT. 

    ---

    Your math is IMO utter and complete nonsense - 4.4*239 is a meaningless and unphysical multiplication, 255K is only of interest as the emissions of a perfect blackbody radiating 239 W/m2 (ie in Gedankenexperiments), while the Earth is a real graybody where emissivity throttles radiative output to space, you confuse cause and effect (TOA imbalances from emissivity or albedo changes lead to changed surface temperatures that can once again radiate the same as incoming - you have the temperature change coming first), Snowball Earth is a red herring in regards to current climate change, etc etc. Nonsense on top of nonsense, complicated arguments without basis that seem (IMO) intended to dazzle and confuse, not science. 

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    Moderator Response:

    [RH] Looking into it.

52. MA Rodger at 21:59 PM on 15 July, 2015

    Michael Fitzgerald @47.

    I concur with your first sentence. However, addressing these three logical outcomes from your '239-Steps' test is made difficult by your apparent denial of the snowball Earth mechanism ('apparent' in that I am left to interpret the moderation "(snip)" @47).

    And in addition to that apparent difficulty, I do not concur with your second sentence. Why do you write that I "seem to believe that no reasonably supportable function consistent with a sensitivity of 0.8C per W/m^2 at an average surface temperature of 288K exists."? My comment @40 surely suggests the exact opposite.

    In the round, your comment @47 simply re-states your problematical 239-Steps test in a different form. I'm not sure how that would be any help to 'man nor beast'.

    Within all your inconsequential/nonsensical blather @47, I note you tell us "170K ... below which the feedback is zero". On what do you base that assertion?

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53. MIchael Fitzgerald at 11:01 AM on 16 July, 2015

    MA Rodger, #52

    I never denied anything about snowball Earth. Of course I understand the evidence that suggests it may have occurred as many as 3 times, the most recent about 500-800 million years ago and others going back billions of years. All I did was offer a possible hypothesis for why they might arise and why they don't persist, which as far as I'm concerned, anything anyone says about this, published or not, can only be speculative, especially given the how much the Sun, orbit, surface and atmosphere has changed over billions of years.

    If you know of a reasonable quantification for the sensitivity as a function of temperature, please tell me what it is. This is what I've been asking for all along, yet nothing has been forthcoming except arguments that it doesn't apply because feedbacks change as a function of temperature. I completely agree that feedbacks change, but it's completely quantifiable by starting with the slope of SB and increase it when positive feedback arises and decrease it when negative feedback arises. The problem is that there's no version of this form that can lead to a monotonic temperature increase that ends up at a sensitivity of 0.8C per W/m^2 @ 288K. BTW, its perfectly OK to say that the feedback is so negative along the way, that no temperature increase occurs as the input energy increases, but I can't conceive of any negative feedback with this much effect and that can persist over a wide enough range of input power to end up requiring a sensitivity of 0.8C per W/m^2 at 288K, plus there's the T^4 issue to deal with. Denying that the test applies only weakens your case for a high sensitivity.

    The 170K comes from something someone said about no GHG effect below this temperature. This means that there is no atmospheric CO2, water vapor, or clouds, thus no feedback. If you can quantify a feedback mechanism below 170K, please tell me what it is, but if its positive feedback, it only makes it more difficult to arrive at a function that ends up at 0.8C per W/m^2 @ 288K.

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54. MIchael Fitzgerald at 11:03 AM on 16 July, 2015

    KR,

    Actually, it was his post here (#35.1) that inspired my question.

    
    http://joannenova.com.au/2015/07/climate-scientists-more-scared-of-an-inquiry-into-the-science-than-they-are-of-climate-change/

    
    Based on your denial that these questions even have answers, co2isnotevil appears right and the answers clearly dispute the accepted sensitivity, and this scares many who believe otherwise. I'm also a physicist and his descriptions of the underlying physics are spot on. The climate is certainly complex, but in the final analysis, its macroscopic behavior must still obey the laws of physics. The many inconsistencies pointed out in the threads you referenced is astonishing, especially how so many laws of physics must be violated to support a high sensitivity. I still have trouble believing how so many smart people can be so wrong in so many ways about something so important, but the evidence presented is powerfully compelling.

    One piece of evidence is a plot of monthly average surface temperatures vs. monthly average emissions by the planet, extracted from decades of satellite measurements, where the only possible conclusion is that the Earth is nearly an ideal gray body from space with an emissivity of 0.62 and answers the question about whether an ideal gray body model is sufficient for modeling climate change or at least bounding the sensitivity. The theoretical range of the sensitivity for an ideal gray body model of Earth is in the range of 0.2 – 0.3 and spans most of the estimates from the so called 'consensus of skeptics' and is far from the 0.4 – 1.2 range asserted by the 'IPCC consensus'. There's no room for compromise where both sides can say they were right and that's part of the problem. I predict that a sensitivity significantly less than the accepted lower limit of 0.4 must inevitably be accepted, and when it is, climate science will be disrupted in a way that no field of science has ever experienced and it will be both interesting and scary to watch with many far reaching repercussions.

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55. MIchael Fitzgerald at 11:04 AM on 16 July, 2015

    To All,

    I really wish you all would stick to the science. One thing you can learn from co2isnotevil's posts is that he doesn't constantly berate his opponents for having an opposing position, only attacks the position itself and usually quite effectively. Constantly berating those with opposing positions only makes you appear insecure about yours which only serves to weaken your case.

    Michael

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    Moderator Response:

    [JH] Off-topic and insulting.  

56. PhilippeChantreau at 13:18 PM on 16 July, 2015

    Unless of course said position is lacking merit and has already been considered and found to not deserve further consideration. Then continued repetition will obviously lead to more pointed comments.

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57. MA Rodger at 19:06 PM on 16 July, 2015

    Michael Fitzgerald @53.

    Thank you for this comment @53. Unlike previous offerings, it can be read through and the meaning gleaned in one reading.

    170K? "Someone said". This is a bit tenuous. It sounds like somebody is adopting an arbitrary "at -100ºC". But what if it was effectively only -40ºC?

    Your basic thesis here is that if ECS=3ºC, feedback has to be contributing two-times the warming of the original forcing. (I note you inflate this to 3.3x but I'm pretty sure that is wrong & let's tackle one thing at a time.) So, very very simplisitically, if there is 150Wm^-2 of forcing but the planet has 239Wm^-2 of forced warming, at a ratio of 2:1, dropping that level of external forcing we would run out of feedback by 239-(150/2)=164Wm^-2=(from Stefan-Botlzmann)232K=-42ºC.

    Of course, once the mechanisms that actually create the feedbacks are considered, the simplistic use of a 2:1 ratio will (and the ballpark -40ºC may) prove complete pants. I think it will also demonstrate how much of a theoretical thought experiment it is that you are pursuing.

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58. John Hartz at 23:31 PM on 16 July, 2015

    Moderation Comment:

    From here on out, please avoid the temptation to respond to Michael Fitzgerald. 

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59. KR at 00:44 AM on 17 July, 2015

    Michael Fitzgerald - In deference to the moderators, I will keep this reasonably short. But I will make the comment, primarily for the benefit of other readers who might find this puzzling.

    • In the range between a zero atmosphere 255K Earth and actual conditions, there are multiple non-linearities such as the presence of water vapor - attempting a linear extrapolation (as George White does) from the thought experiment is a fools game. 
    • GW's hurricane comments are utterly red herrings, as I pointed out earlier.
    • The energy balance at TOA is a boundary condition - surface temperatures are a product of TOA energy conservation and the atmosphere. Jumping back and forth as GW does between surface and TOA temps, and expecting the scalars from one to apply to the other, is nonsense.

    GW's claims are complicated BS - for a more complete discussion of why, read the threads here, here and here, where his very basic errors were pointed out by many people (in comments that were ignored on his part). If you are actually interested in the science you can do far better than uncritically following an unpublished blogger who is making up their own (unrealistic and silly) physics.

    GW plays Galileo, thinking that he's overturned all the last 150 years of climate science, when his (unpublished and unreviewed) claims add up to claiming that 2+2=5, and why doesn't everyone recognize that? The 'Galileo gambit' only works if you are correct. He is not. 

    ---

    For anyone truly interested in the science basics, I suggest starting with the RealClimate summary here, and Spencer Weart's Discovery of Global Warming history (with lots of primary references) here. In the meantime, Michael, I will ignore further posts from you until/unless they actually intersect with real physics. 

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60. MIchael Fitzgerald at 11:02 AM on 17 July, 2015

    KR, re #57

    Thank you, this is what I was asking from you. FYI, the 170K value came from either you or Tom, so since you don't remember saying this, it must have come from Tom. But lets go with your suggestion that feedbacks don't kick in until -40C. The first 167 W/m^2 get us to -40C (233K) leaving 73 W/m^2 to get to 288K. If we assume a sensitivity of 0.75 for the remaining 73 W/m^2, we get to 288K.

    There's still a problem with this. If the increase in sensitivity is consequential to an increase in feedback, all of the accumulated W/m^2 of forcing are subject to the same new feedback influences and you should expect a large change in temperature as the feedback kicks in and is applied to the accumulated W/m^2 and a smaller change thereafter as only the incremental W/m^2 matters as long as feedback remains constant. If we assume a step change in feedback at 40C that results in increasing the sensitivity from 0.35 to 0.75 the first 167 W/m^2 now acts like 167*.75/.35 = 358 W/m^2 and the temperature jumps to 281.8K (48.8C per W/m^2), thereafter to increase by 0.75C per W/m^2, resulting in a final temperature of 336.6K which is obviously too high. How can you modify your quantification of sensitivity to account for this?

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61. MIchael Fitzgerald at 11:18 AM on 17 July, 2015

    KR,

    Perhaps the math will help you see the nature of this problem more clearly. Consider that the Earth from space looks like a gray body whose temperature is the surface temperature and whose emissivity is 240 W/m^2 / 390 W/m^2 = 0.62. From this, we can readily quantify the planets behavior as follows:

    If P is the planet's emissions, T is the surface temperature, ε is the effective emissivity of a gray body model of the planet and σ is the Stefan-Boltzmann constant (5.67E-8), express P as,
    1) P = εσT^4
    and quantify the LTE sensitivity as a function of state, λ(P), as the change in T consequential to a change in P. We can do this because the definition of the steady state is when the planet emissions P are equal to the net power arriving from the Sun, thus incremental P conforms to the definition of forcing.
    2) λ(P) = dT/dP
    Solving 1) for T and differentiating, we get,
    3) T = (P/(εσ))^0.25
    4) u = (P/(εσ))^0.5
    5) T = u^0.5
    6) dT/dP = .5/u^.5 * du/dP
    7) dT/dP = .5/u^.5 * .5/u * 1/(εσ) = λ(P)
    8) λ(P) = (P^-0.75 * (εσ)^-0.25) / 4

    For ε = 0.62 and P = 240 W/m^2, λ(P) = 0.3, which is the slope of the SB curve at 255K.

    Integrating dT/dP (the sensitivity function λ(P)) from P = 0 to 240 W/m^2 results in T = 288K, which is the expected average temperature of the surface at 240 W/m^2 of input power. The definite integral is the value of 3) at P = 240 W/m^2 since the integral of 8) is 3) and T(P) is 0 when P = 0. While this sensitivity function is relative to input power, it can also be expressed as a function of equivalent surface temperature, T.

    9) λ(T) = T^-3 / (4εσ)

    At T = 288K, λ(T) has the same value as λ(P) at P = 240 W/m^2. These formulations for λ(P) and λ(T) are exact for any gray body at any emissivity and applying this model to the Earth is consistent with all measured averages, albeit with a sensitivity lower than expected. The only way to morph this behavior is to make ε a function of P or T, which we know to be the case anyway, as increasing GHG's will decrease ε. Up to about 233K (for KR's hypothetical that feedback kicks in at -40C), ε = 1 and gradually decreases until ε = .62 at 288K. If ε is a function of P, and we know that feedback can only directly affect ε, so a change in ε is applied to all P, not just the incremental P.

    The sensitivity as a function of state can be be rewritten as one component dependent on P, λP(P), times a dimensionless component dependent on ε, λε(ε), such that λε(ε) = 1 at ε = 1.

    10) λ(P, ε) = λP(P) * λε(ε)
    11) λP(P) = (P^-0.75 * σ^-0.25) / 4
    12) λε(ε) = ε^-0.25

    At the current steady state when ε = 0.62 and P = 240 W/m^2, λε(ε) = 1.13 and λP(P) = 0.266 whose product λ(P, ε) = 0.3. For λ(P, ε) = 0.8 keeping P constant, the required λε(ε) is 1.13*(0.8/0.3) = 3.01. The required ε to achieve this is about 0.012 which at 390 W/m^2 of surface emissions results in 4.7 W/m^2 of emissions by the planet, which is obviously wrong as 240 W/m^2 are required. Splitting λ(T) into a temperature component and a dimensionless component dependent on the emissivity leads to a slightly different impossible result.

    What this tells us is that a sensitivity λ(P, ε) = 0.8C per W/m^2 is in conflict with the emissivity of the planet, ε and the power emitted by the planet, P. Either the Stefan-Boltzmann Law doesn't apply to the climate or the sensitivity is not 0.8C per W/m^2.

    Presumably, this analysis will not convince you that a sensitivity of 0.8C per W/m^2 is impossible, so what will? Can you supply mathematical and physics proof that the SB Law is irrelevant to how the climate behaves?

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    Moderator Response:

    [PS] Are you or are you not George White?

    [PS] I find it hard to believe there are two people in the world going for this nonsense and I think we can conclude that "Michael" is actually George still trying to flog his unphysical maths. Please do not respond.

62. Tom Curtis at 13:32 PM on 17 July, 2015

    Michael Fitzgerald @60, here are the important temperatures for gases that are currently significant, or have in the past been significant in the Earth's atmosphere.  Of these, methane and ammonia were major players (along with nitrogen and CO2) prior to the evolution of photosynthesis approximately 2.4 billion years ago.  Neither can survive long in an oxidizing atmosphere, so they have been bit players since then.  In the list below, I have distinguished greenhouse gases by bolding them, and underlined the group of gases including the two major components of the Earth's current atmosphere.

    Molecule  Freezing Point, Boiling/sublimation point

    Helium NA, 4.15 K

    Hydrogen 13.95 K, 20.15 K

    Nitrogen  63.15 K, 77.15 K

    Argon 83.75,  87.35 K

    Oxygen 54.35 K,  90.15 K

    Methane 91.15 K,  111.65 K

    NO2 182.29 K,  184.67 K

    CO2 194.65 K, 194.65 K

    Ammonia 195.42 K,  237.65 K

    H2O 273.15 K,  373.15 K

    Considering an Earth with a modern atmosphere, and of a similar age to the Earth, but which existed far from any star, the total energy at the surface would be a very evenly distrubuted 0.1 W/m^2, generating a surface temperature of approximately 36 K.  That is sufficient to "boil" Helium and Hydrogen, but no other of the gases that constitute the Earth's atmosphere.  So, at that temperature the Earth would be a frozen wasteland with a very thin atmosphere of helium and hydrogen, with hydrogen being the largest component.  Importantly, because the atmosphere would be so thin, and because there would be no liquids on the surface of the Earth, the formula for the Earth's average temperature would be:

    (((Geothermal + (TSI*(1 - albedo))/2)/σ)^0.25 + (geothermal/σ)^0.25)/2

    This formula is used because the lack of heat transfer means daytime temperatures would become much hotter night time temperatures, thereby emiting much more energy to space.  The result averages out to a lower temperature than that derived using the more common formula (which assumes exactly equal temperatures across the entire globe).  The formula will not be perfectly accurate, but will generate a reasonable estimate.  The more common formula is also only approximate, slightly overestimating expected temperatures (because there is some temperature variation between night and day, summer and winter and across geographical divisions).

    Further, at absolute zero (or 36 K), the Earth's albedo would not be 0.3.  Rather, it would be entirely covered by ice and snow, giving it an albedo between 0.6 and 0.9 (depending on the purity of the snow).  In my estimates discussed below I shall use the more conservative figure of 0.6.

    Using that formula and estimated albedo, we can determine a no feedback estimate of global temperatures.  That is, we can determine the final global mean temperature if you really started at absolute zero, and gradually increased TSI up to 1360 W/m^2 (the current best estimate of its value).  That temperature turns out to be 150 K.  That is, it turns out to be too low to sublimate CO2, let alone to melt ice.  Indeed, even with an albedo of 0.3, and with more or less equal temperatures across the globe, the global mean temperature would be around 255 K, not enough to allow unfrozen water at the equator.  Given the importance of water in heat transport, and given the importance of the greenhouse effect in equalizing temperatures at the poles (the polar amplification effect), the temperature would in fact be less than that.

    Given this we see the decietfulness of CO2isnotevil's challenge.  By setting the albedo at 0.3, he has already included all albedo feedbacks in his calculation of the "no feedback" temperature response (255 K).  Indeed, he has also included the surface heat transfer feedbacks as well, by using the standard formula.  If he is going to include those in the base calculation, he needs to exclude them from the Climate Sensitivity Parameter (λ), reducing it from 0.8 to about 0.5 (ie, twice the planck response).  Worse, by framing it in terms of energy in an the TOA, he also excludes any greenhouse effect (forcing or feedback) from the calculation.  So, his challenge is for us to find the albedo and greenhouse feedbacks in an equation that excludes them by design.

    We also see a fundamental problem with your framing of his challenge.  If we indeed started with a cool Earth, and gradually turned up the heat we would still be in a snowball Earth.  The same conditions which give us our currently very livable Earth are consistent with one entirely frozen depending on whether you start with cold conditions and warm up, or with warm conditions and cool down.

    As it turns out, cooling down from a warm condition, if we reduce the atmospheric greenhouse effect by just 22 W/m^2, the Earth's temperature will cool by 21 C.  That estimate excludes any growth of ice sheets, which if allowed would allow the temperatures to plummet even further.  Those results mean that averaged over the last 22 W/m^2 of warming, λ = 0.95.

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    Moderator Response:

    [PS] Numerous people on numerous forums have tried to explain physics to George White over years including here. I doubt further efforts will be effective.

63. Tom Curtis at 14:17 PM on 17 July, 2015

    PS, sorry but my post @61 was made before I saw your inline @61, or 61 at all.

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    Moderator Response:

    [PS] I deleted other stuff from George, but then on reflection, he said:

    "If mathematical proof is insufficient to demonstrate that a sensitivity of 0.8C per W/m^2 is impossible, what proof would convince you?"

    George, mathematical proof only proves a mathematical postulate. A mathematical model that doesnt capture actual physics is worthless. So to convince me and the rest of science, you need an observation/experiment where your model produces a closer match than existing models. Given the stress-tested nature of textbook physics, I'll back that till you can produce that experiment.

64. MA Rodger at 21:45 PM on 17 July, 2015

    Moderator Response @63.

    This may or may not be George Michael we are experiencing on this thread, or an accomplice, or involving accomplices; whoever this entity is, I feel it is not worth allowing them to continue here. I would argue this even if there were no possibility of it being George Michael. I would argue this, but not on any grounds that feature in the comments policy.

    This Michael Fitzgerald/Whoever is repeatedly and exasperatingly wrong, or perhaps more correctly 'presenting concealed nonsense.' Where this surely becomes inadmissible is when the concealment is deliberate.

    His obfuscation always hovered on the edge. Consider his 'contribution' @60. After beng asked directly twice for the source for his170K (the lower limit of GHG operation), he at last hand-waves at "Tom" and the source can thus be tracked down to an off-handed comment @8 by Tom Curtis. #60 then actually says it agrees with a response to him @57 but this is only evident with a very dedicated reading @60. And the remaining bulk of #60 is pure madness. (It is saying that when feedback begins to apply at some threshold with rising temperature, the temperature leaps up because the feedback suddenly applies to all the original forcing below the threashold as well as the additional forcing above the threashold. And voila, we can arrive at the answer we first thought of.) As I say, pure madness, although this could still be a genuine but very very stupid person who fails to explain themselves clearly.

    There may be room for such stupidity at SkS but @61(which also is inconsistent with #60) the intentional concealment cannot be ignored.

    There can be no denying that the comment @61 is intentionally complicated to dress up the argument. Thus it unnecessarily breaks into differentiation-by-parts but, in so doing, makes a mistake which mysteriously corrects itself when solved. And after that slip, the laborious 'morphing of ε' gives exactly the same outcome as it did before ε was 'morphed'. This is not just "a mathematical model that doesnt capture actual physics". It is scientific madness, the product of a fool and one who is actually trying to hide his method.

    I would suggest such a one has no place here.

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65. KR at 00:43 AM on 18 July, 2015

    MA Rodger - That's an excellent review of Michael/George White's nonsense on this thread.

    Note that I'm quite certain it's George - even a slavish acolyte would tend to avoid the rather obvious mistakes shown (or at the very least make different ones). Gobs of mixed-up math noise propping up his unsupported conclusions - IMO those conclusions preceded and override the evidence for him. 

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    Moderator Response:

    [DB] Michael/George White is no longer a participating member of this site.

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