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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 101301 to 101350:

  1. Human CO2 is a tiny % of CO2 emissions
    Regarding what drives the CO2: the temperature at point A rises seasonally. As a result the solubiity of CO2 in the ocean decreases at A and therefore some CO2 comes out of solution increasing the partial pressure (proceeding in the direction of the new equilibrium at the higher temperature). This increased partial pressure is swept by moving air masses to point B where the temperature does not increase as much, remains the same, or even decreases. At point B the CO2 spontaneously dissolves because the partial pressure exceeds the equilirium value for that temperature and concentration. Thus a transport of the CO2 is "driven" by the seaonal temperature changes. The process is reversed when the seanon changes back to the starting point. I have another, I think more important, question: Why is the condition of elecrical neutralty not brought into the discussion. All solutions, including the ocean, are to a very, vary close approximation electrically neutral. By my calculation of the total carbon dioxide 93.3% is present as bicaronate and carbonate. If 300 plus GT of carbon dioxide moves from A to B that amounts to about 7 times 10 to the 14th moles. The concentration of the major CO2 containing species in the ocean (bicarbonate) is about 0.0025 molal but that is not free to exchange without some negative charge increase or positive charge decrease. It seems to me possible that raises a serious problem for the 300 GT of supposed transport. I can do the following calculations: 1. assume equilibrium at point A (all CO2 bearing aqueous species, hydrogen and hydroxide ions, water and CO2 gas)at 288K, 2. assume a similar equilibrium at point B at 298K, 3 find the difference beyween the equilibrium CO2 partial pressures at A and B,3. find the mass of air required to move 300 GT of excess (at 288K) CO2. Does anyone want me to do that? I am now going to start a new thread to answer the questions about my ppt. So the two topics don't become confused.
  2. How Jo Nova doesn't get the tropospheric hot spot
    Schnorkel. Those papers you mention were published barely 2 months before the Thorne review was published. There are often journal rules about making substantial changes to papers late in the production process. It's likely those papers appeared too late to be included. It's not as if Thorne doesn't quote Christy. I count 31 citations of papers with Christy as coauthor. I think you can (and should) do better.
  3. 2nd law of thermodynamics contradicts greenhouse theory
    VeryTallGuy, thanks! The figure in your comment here is the exact one I had in mind when composing this comment in the other thread. I couldn't remember where I'd seen that figure (from Soden & Held, 2000), spent a lot of time looking for it, and finally ran across the similar (but not quite as good) version at Chris Colose's website.
  4. 2nd law of thermodynamics contradicts greenhouse theory
    Fred> Assume that the sink is capable of absorbing all the energy radiated by the source. This is an incorrect assumption for your simple model, and it invalidates your conclusions. Instead of absorbing all the energy, picture your sink absorbing a fraction of the energy emitted by the source, with that fraction increasing as the absorptivity of the sink increases. You will find that your simple model does indeed predict warming with increasing absorptivity of your sink.
  5. The 2nd law of thermodynamics and the greenhouse effect
    damorbel as you may have noticed, I didn't continue the discussion with you before. Also, from my last comment it should be clear that I don't think you have any real interest in the science. Many people here spent a lot of time highlighting your errors and providing solid scientific ground. At a point you even said that you know better than textbooks on basic science. In response, you kept moving the goalpost, as it should be clear looking back at the discussion. There ìs a wealth of good informations out there, if your interest in the science was genuine your first step would have been to check your claims or accept the suggestions given here. My conclusion is that you're just trying to hijack the discussion and it's not my wish to provide more fuel.
  6. How Jo Nova doesn't get the tropospheric hot spot
    Ricardo and Mouncounter Took your advice on board and re-read Thorne et al again. But was puzzled not to see any reference to relevant literature in this meta-review, i.e. no mention of Christy et al ("What Do Observational Datasets Say about Modeled Tropospheric Temperature Trends since 1979?") in Remote Sensing 2010, 2, 2148-2169; doi:10.3390/rs2092148. Nor could I see any reference within to McKitrick et al's paper "Panel and Multivariate Methods for Tests of Trend Equivalence in Climate Data Series" in Atmospheric Science Letters. Or should we just say Christy and McKitrick don't count? That doesn't look good. Surely we can engage the sceptics on their own ground. We risk being seen as too timid to robustly confront contrary arguments. I mean, its sort of like Thorne et al just ignored people saying stuff they didn't like and focussed on the work of people who agreed with them, like Santer. It makes me think the Thorne meta-review paper you referred me to risks being seen as an attempt to get around the problem that the warming in the upper troposphere which the computer models tell us should be there, is really not there. Also I think that sceptics could see the use of the 'adiabatic' term and the "adjustments" terms as just another way to wriggle out of what they would say is the fact that human-induced climate change's hot spot is away on vacation. Surely we can do better than this.
  7. An Even Cloudier Outlook for Low Climate Sensitivity
    "The explanation for El Nino and La Nina involves a circular argument. Changes in sea surface temperature are both the cause and consequence of wind fluctuations." I don't like that phrasing. It's not really a circular "argument" (which implies logical fallacy), but an argument for reinforcing system of mechanisms. Those reinforcing mechanisms form feedbacks, which are what gives the system enough momentum to create the large shift in heat distribution, winds and ocean currents observed during El Nino and La Nina.
  8. 2nd law of thermodynamics contradicts greenhouse theory
    Fred Staples - "Would you agree, Ned, that there is ample scope here for rational scepticism about the impact of increased CO2 in the atmosphere?" I would say that there is not. Greenhouse gases reduce the efficiency of emission (emissivity), as is clearly seen by satellite spectra of the Earth. Given the P = e * s * A * T^4 relationship of Power to emissivity, Stephen-Boltzmann constant, Area, and Temperature, if the emissivity goes down temperature must rise to radiate the same power.
  9. 2nd law of thermodynamics contradicts greenhouse theory
    Fred Staples "Woods tried to test it by building two greenhouses – one radiative (ie OLR absorbent) and one non-radiative. Their internal temperatures were the same." Which proves very nicely that greenhouses work by limiting convection rather than by absorbing radiation. It tells us nothing about the atmospheric greenhouse effect other than that it's poorly named. "And if we do believe it, ignoring Woods, what will happen if we increase the absorption of the atmosphere? Its temperature cannot increase because it must continue to radiate W to space. The source to sink temperature difference must also remain the same. So nothing will happen." You're very nearly correct. The effective radiating temperature does indeed stay the same, but it moves upwards in the atmosphere. The result is that the surface temperature must rise This is the best simple explanation I've ever seen of it and may clarify for you (thanks to Science of Doom): Soden & Held, 2000
  10. 2nd law of thermodynamics contradicts greenhouse theory
    Fred Staples wrote "if we increase the absorption of the atmosphere? Its temperature cannot increase because it must continue to radiate W to space. The source to sink temperature difference must also remain the same. So nothing will happen." Fred, you are using only the rules for equilibrium, but by increasing the absorption of the sink you've pushed it out of equilibrium. While the sink moves toward a new equilibrium, additional rules apply. Increased absorption by definition means that the sink retains some of the energy W that hits it. There is no rule insisting that the retained energy instantly be radiated. Instead, the rule about how much energy is radiated depends on the temperature of the sink. The temperature of the sink does not rise enough to cause all of the newly retained energy to be radiated.
  11. It's the sun
    Although that is interesting, it does not actually anser the question about the correlation between solar activity and surface temperatures.
    Moderator Response: [Daniel Bailey] I addressed everything in your original comment that had a question mark attached. As to your question in this comment, did you read the original post? How about the Intermediate version? Or the Advanced version?
  12. The 2nd law of thermodynamics and the greenhouse effect
    Re #255 Riccardo, you wrote:- "One more bit of misinformation added by....." And the correct version is....(?)
  13. Greenland Ice Sheet outlet glaciers ice loss: an overview
    Ian Howat of Ohio State and Ian Joughin from the U Washington have published so many fine papers it is easy to refer to the wrong one. The correct paper for the 32 glaciers is Howat et al (2008)
    Moderator Response: [Daniel Bailey] Thanks for the update on that; fixed texts.
  14. Greenland Ice Sheet outlet glaciers ice loss: an overview
    Daniel having quickly scanned (hence I might I have missed something) the Howat paper you link to, it looks like HR @ 2 is correct. The paper you refer to investigates 6 glaciers. Can you clarify the research you are refering to?? Are you just referencing that one paper or were there others that make up the 32 glaciers you state. Quote: "We examine data from six glaciers with ice fronts wider than 3 km."
    Moderator Response: [Daniel Bailey] Fixed per Mauri's comment below. Thanks for the heads-up!
  15. 2nd law of thermodynamics contradicts greenhouse theory
    “The net heat flux is from the surface to the atmosphere; it's just a smaller flux than it would have been if the atmosphere weren't there (or didn't contain greenhouse gases)”. “This is all completely uncontroversial among physicists, earth and planetary scientists, and others who deal with radiation balances in their work. There is no fertile ground for AGW-skepticism here” In your post, Ned, there remains a failure to differentiate between heat and energy which is at the heart of the confusion in most of the AGW blogs. Heat (the ability to do work or raise temperature) is, by definition, the net transfer of energy between two bodies. It is wrong to consider source to sink, and sink to source, energy flows in isolation. That way madness (and perpetual motion) lies. That is why the revised Trenberth diagram is vastly superior to its misleading predecessor. Whether or not energy can do anything at all depends on its surroundings. That is why there are cooling towers on power station sites. The backward radiation on which SOD harps at inordinate length is the negative term in the Stefan-Bolzmann equation. Given that, with a few simplifying assumptions, it is very easy to calculate the greenhouse effect. Assume a spherical, heated, source in a vacuum, in direct contact with the absolute (more or less) zero of space. If the temperature of the source is Tsource, it will radiate energy, W, at a rate proportional to the fourth power of Tsource. Now surround the source with a spherical sink, close enough for us to neglect surface area corrections and (this is a thought experiment) with zero resistance to thermal energy, so that we can ignore temperature gradients. Assume that the sink is capable of absorbing all the energy radiated by the source. The sink will warm until, at equilibrium, it radiates to space the original source energy. In other words, to Tsink will rise to equal Tsource. Meanwhile, the source must warm to Tsource1 so that it can radiate the original input energy to the sink. That energy output, W, will now be proportional to the difference between the fourth power of the new source temperature, Tsource1 and the sink temperature, Tsink which will have risen to Tsource. In other words, Tsource1 to the fourth – Tsink to the fourth = Tsink to the fourth, because the sink is radiating the original energy, W, to space. But Tsink = T Source, the original source temperature, so : The new source temperature (to the fourth) = 2 * the original source temperature (to the fourth). So, finally, Tsource 1/Tsource = fourth root of 2 = 1.19 Since the moon is at 255K, we arrive at a plausible explanation of the greenhouse effect (0.19*255= 48.5K). The atmosphere does not warm the earth directly in a second law violating way; instead it acts as a radiative insulating blanket. Do we believe this explanation, Ned? Woods tried to test it by building two greenhouses – one radiative (ie OLR absorbent) and one non-radiative. Their internal temperatures were the same. And if we do believe it, ignoring Woods, what will happen if we increase the absorption of the atmosphere? Its temperature cannot increase because it must continue to radiate W to space. The source to sink temperature difference must also remain the same. So nothing will happen. Would you agree, Ned, that there is ample scope here for rational scepticism about the impact of increased CO2 in the atmosphere?
  16. An Even Cloudier Outlook for Low Climate Sensitivity
    #105 dhogaza, "Dessler (and everyone except Spencer) is saying that ENSO causes temperature changes which lead to cloud changes which lead to feedback. Not *all* cloud changes, as Spencer is implying..." Dessler says average cloud changes cause positive feedback. He doesn't know which, so it could be "all" cloud changes although that is unlikely. Some cloud changes also cause SST gradients which cause wind which will enhance or detract from El Nino or La Nina. That effect may be minor and it is likely not to be a "cause" in the most basic sense since no research I have seen shows that any particular patterns of clouds precede El Nino. For La Nina, there are the clouds, rain, pressure gradient and other effects of El Nino that play a role. Saying clouds cause La Nina and ignoring the rest is not supported. Here's a paper http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.144.83&rep=rep1&type=pdf that states: "The explanation for El Nino and La Nina involves a circular argument. Changes in sea surface temperature are both the cause and consequence of wind fluctuations."
  17. The 2nd law of thermodynamics and the greenhouse effect
    "The thing about the lapse rate is that it is substantially constant at 6.5K/km over the whole planet" One more bit of misinformation added by our hero. Yes, misinformation; given the huge amount of errors thrown here, it can not simply be a lack of knowledge. A bit offtopic but interesting reading from Monbiot.
  18. Greenland Ice Sheet outlet glaciers ice loss: an overview
    #3, Bart, the Wu et al. paper has been discussed in detail here.
  19. Greenland Ice Sheet outlet glaciers ice loss: an overview
    What's the source of Fig 1? It seems a continuation of the numbers as presented in Velicogna (2009), without accounting for the criticism of Wu et al (2010). That's not to say that Wu et al should be regarded as 'the truth and nothing but the truth', but I guess neither should Velicogna.
    Moderator Response: [Daniel Bailey] That is just now being presented by John Wahr at AGU.
  20. Greenland Ice Sheet outlet glaciers ice loss: an overview
    I've only read the Howat 2010 paper so far but you seem to have got a few details wrong. This is what you say "Howat and others (2010) examined changes in terminus position, surface elevation and flow on 32 glaciers along the southeast coast of Greenland from 2000-2006. They affirmed that speedup results from loss of resistive stress at the front during retreat. Many retreats began with an increase in thinning rates near the front in the summer of 2003, a year of record high coastal-air and sea-surface temperatures." In fact it only studied 6 glaciers (2000-2009). Speedup is associated with reduced sea ice/melange conditions, not glacier thinning, and is correlated only with SST not with air temperature.
    Moderator Response: [Daniel Bailey] Fixed per Mauri's comment below. Thanks for the heads-up!
  21. The 2nd law of thermodynamics and the greenhouse effect
    Re #252 Joe Blog you wrote:- "the energy contained is due to energy in vrs path length out. As can be seen in the graphic in NEDs post." The diagram in Ned's post shows the temperature of the surface and atmosphere changing without the height of the tropopause changing, this is absurd; check the gas laws, PV = RT. Further you wrote:- "The stratosphere is an entirely different ...UV through O3, ... But UV heats it from the top down." Which is a very important point since this 'downward' (actually incoming) radiation is absorbed (by O2 as well as O3, the O2 absorption creates the O3) raising the temperature and causing an inversion. If the back radiation of the GHE hypothesis was warming the surface it would also warm the other GHGs on its way down, just like the solar UV warms in the troposphere, also causing an inversion.
  22. Ocean acidification isn't serious
    Muoncounter @ 49 - Notice the trend in the NOAA graphic around Antarctica. Consistent with the upwelling of warmer deep ocean water around the "citadel of ice".
  23. The 2nd law of thermodynamics and the greenhouse effect
    Re #249 Ned you wrote:- "(due to GHGs), and keeping the lapse rate constant (not due to GHGs), implies warming of the surface. " Implies? isn't this a scientific matter, better please! I first saw this in John Houghton's book 'Raising altitude of emission'. You should look at the evidence. The height of the tropopause , which you are saying is changed with GHG concentration, also follows the mean surface temperature as it varies with latitude, so it is clear that the height of the troposphere is also a function of the local planetary temperature which, according to GH theory, is also a function of the albedo. Now what is the effect of CO2, does it decrease the albedo, thus raising the planetary temperature, does it change the lapse rate (as compared with raising the tropopause) or does it warm the surface without affecting either the height of the troposphere or the lapse rate, this last being the 'backradiation' model. Can you say wchich it is? The thing about the lapse rate is that it is substantially constant at 6.5K/km over the whole planet, independent of the local temperature and the height of the tropopause.
  24. A new resource - high rez climate graphics
    Hey Ken, I know OHC is a pet subject of yours, have you seen this?: ANTARCTIC MELTING AS DEEP OCEAN HEAT RISES It'll be an interesting read when it makes it's way into the peer-reviewed literature.
    Moderator Response: Let's please try to keep discussion of science topics consolidated in threads where people will be able to find it. Discussion of ocean heat content should be moved to the appropriate thread (probably Oceans are cooling).
  25. An Even Cloudier Outlook for Low Climate Sensitivity
    Yes...that's the problem. How to move that much heat by some extrinsically driven cloud forcing for long enough to generate the massive heat imbalance one gets with ENSO. Maybe if there was some positive feedback, but that would of course be a feedback and Dessler would still be right. I think he's in a corner.
  26. An Even Cloudier Outlook for Low Climate Sensitivity
    HR: "I don't see the necessary logical jump that says because Spencer is talking about the relationship between deltaT and clouds, and the potential for cause and effect to be reversed here, that he's talking about the relationship between ENSO and cloud" edited: "Spencer is talking about the relationship between deltaT and clouds, and the potential for cause and effect to be reversed here" So reversing the causality arrow between deltaT and clouds when analyzing ENSO data means what, then? Look up "reverse" and "causality" in the dictionary. You essentially saying "just because Spencer claims that clouds cause deltaT (previously thought to be due to ENSO) doesn't mean that Spencer is saying that this causes ENSO". So, then, in what direction does Spencer say the arrow points? Obviously, not from ENSO to temps/clouds ... reversing means that clouds/temps => ENSO.
  27. An Even Cloudier Outlook for Low Climate Sensitivity
    Albatross: "Why has no-one applied a Granger causality test to these data?" Because no one serious disputes the broad outlines of the current understanding of ENSO? Dessler hints that Spencer's explanation is unphysical because of the vast amount of energy that must be transferred to the oceans to make Spencer's claims true. The standard explanation ... well, it falls within understood science. Like so many denialist arguments, if Spencer is right, a WHOLE LOT of science must be overturned that's essentially unrelated to climate science.
  28. An Even Cloudier Outlook for Low Climate Sensitivity
    "I don't see the necessary logical jump that says because Spencer is talking about the relationship between deltaT and clouds, and the potential for cause and effect to be reversed here, that he's talking about the relationship between ENSO and clouds" As Dessler points out, essentially Spencer rejects the standard explanation of ENSO by simply leaving it out of his lead-lag analysis. He presumes his conclusion, in simple terms.
  29. An Even Cloudier Outlook for Low Climate Sensitivity
    "I don't see the necessary logical jump that says because Spencer is talking about the relationship between deltaT and clouds, and the potential for cause and effect to be reversed here, that he's talking about the relationship between ENSO and clouds. The reversal Spencer mentions I think is this" He could have, of course, refuted this strongly in his e-mail exchange with Dessler. He chose not to. Rather, he disambiguated his position in a way not congruent with your interpertation. I appreciate why you want to be his water-carrier here ... but I won't say why, because Cook will delete my post if I do. Oh, BTW, if "Humanity Rules", why are you so dogged in your refutation of the ability of humanity to alter climate? Maybe it's because we don't insist that humanity rules climate, but only affects it ...
  30. An Even Cloudier Outlook for Low Climate Sensitivity
    HR, Pardon the pun, but we are arguing in circles here. I really do not know about this stuff to pass judgement on Spencer's or Dessler's method. Murphy and Forster were less than kind in their critique of SB08, so that doesn't instill much confidence in me that Spencer has gotten this right. The phase space plots are new to me. Maybe someone else here is more familiar with them. Let us not focus too much on the cause of the warming or on ENSO for now-- the question is, regardless of the initial cause, do cloud behave in a way which acts to enhance the initial warming or offset it? Dessler has made a very compelling case that the clouds very likely enhance that warming slightly. And let us not forget that even if negative feedback is operating, it is only very small, and certainly not sufficient to argue that climate sensitivity is low. Why has no-one applied a Granger causality test to these data? I think BPL over at RC has offered, I hope that Dessler takes him up on the offer and that they publish the results.
  31. An Even Cloudier Outlook for Low Climate Sensitivity
    From Spencer 2010 "Evidence for this process was shown by Spencer et al. [2007] in their analysis of a composite of 15 strong tropical intraseasonal oscillations, where strong warming events in the tropical troposphere [el Nino] were accompanied by weak SST cooling. This process was driven by stronger surface winds temporarily enhancing the heat flux from the ocean to the atmosphere." Clouds cause ENSO???? It's far easier to see what these scientists think when you read their science.
  32. A new resource - high rez climate graphics
    Original Post Perhaps John Cook could explain how it is possible for the temperature record to be broadly flat between 1950 and 1975 and the OHC content to rise to 80E21 Joules aro 1958 and disappear without trace by 1970 only to pop back to 80E21 by 1980? Given the huge thermal mass of the oceans - such rates of transfer are well nigh impossible - and do not fit with the generally increasing theoretical forcings from CO2GHG and elevated solar irradiance (since 1920 at least). If your answer is the 'Clean Air Act' please then explain why the IPCC charts show cooling from sulphates steadily increasing up to aro 1970 and then flatlining up to the present.
  33. Human CO2 is a tiny % of CO2 emissions
    #95: "the forces driving CO2 from point A to point B because of a temperature increase at A are reversed when point B warms" CO2 is not driven from one point to another by temperature; rather it is driven by atmospheric circulation. Fisher 2010 presents several good examples; the diagrams in that paper have both physical scale and a time context. "... when the perturbation (i,e the the seasonal remperaure chage) is removed the system returns ti its original state." Unless the system oscillates, as your spring/mass example (and some parts of the climate system) would. "I calculate the forced (no feedbacks) temperature change. I get 1.4 K degrees in the next 100 years. " I don't know how to evaluate that statement without further information: such as what do you assume for climate sensitivity (often expressed as degC/CO2 doubling), what emissions scenario do you use and why no feedbacks? If you would care to share those key assumptions, certainly some of the folks around here more knowledgeable than I would have some helpful input.
  34. An Even Cloudier Outlook for Low Climate Sensitivity
    dhogaza I don't see the necessary logical jump that says because Spencer is talking about the relationship between deltaT and clouds, and the potential for cause and effect to be reversed here, that he's talking about the relationship between ENSO and clouds. The reversal Spencer mentions I think is this ENSO>clouds>temperature (internal forcing) ENSO>temperature>clouds (feedback) that seems to be the content of his publication anyway. As Spencer says there is no need to put clouds before ENSO. I actually think in the email exchange that in large parts they talking at odds to each other which as our discussion suggests is more likely to generate heat than light. It wouldn't be surprising given that both believe the other is missing the important point. But let's agree there is greater precision in the language used in the peer-reviewed papers and focus on what they say. Phase space plots anybody?
  35. Human CO2 is a tiny % of CO2 emissions
    P.S. I just read my submission above and noticed all the typos. I am afraid I am not much of a typist (or proofreader for that matter).
  36. Human CO2 is a tiny % of CO2 emissions
    The fact that I believe it to be bad science is simply that the figure provided none of the information which is given above concerning the distances and times involved. To simply cite a quantity like 332 GT and call it a flux is counterproductive. If it had been said that the arrows correspond to so many GT traveling so many kms during the course of a year I would have had no problem with the figure. As you say, the deniers want to use these numbers to obfuscate the role of human production and the fact that they do not negate the conclusion that human production is the primary cause of GW, it seems to me, depends fundamentally on the fact that the fluxes travel back and forth i.e. the temperature changes that drive them reverse with the seasons so that "what goes around comes around". In other words, I would say that the forces driving CO2 from point A to point B because of a temperature increase at A are reversed when point B warms and the oppositely directed flux is driven by the by the (almost) exacty oppposing forces to return the system to (nearly)its original state. In fact i would liken the situation to streching a spring - it is an essential physcal requirment that when the perturbation (i,e the the seasonal remperaure chage) is removed the system returns ti its original state. At any rate this works for me. But a vague arrow going off into heaven knows where destroys the coherence of the picture. With the imagery of Fig. 7.3 it looks as though the CO2 leaves the ocean randomly (that's the way the deniers really like to think of it) and goes off to any old place. It seems to me that the figure, when used, would benefit enormously from some elements of Stephen Baines comments given above. To calibrate where i am coming from, I taught and did research in Physical Chemistry for nearly forty years and decided when I retired in 2000 to see if I could bring P. Chem. to bear on my understanding of GW. I have developed a ppt that generalizes Beer's Law to the case of braodband, diffuse transmittance and then, using spectroscopic data determined nearly 50 years ago I calculate the forced (no feedbacks) temperature change. I get 1.4 K degrees in the next 100 years.
  37. An Even Cloudier Outlook for Low Climate Sensitivity
    I don't think HR's bothered to read the Dessler/Spencer exchange. Dessler's last post points out the logical flaw in Spencer's reasoning ...
  38. An Even Cloudier Outlook for Low Climate Sensitivity
    "It's difficult to know where to take this particular arguement when Spencer has explicitly stated on his blog that he does not support the idea that ENSO are caused by clouds." Yet he explicitly states the opposite in his e-mails to Dessler. And he says things in his blog that are explicitly incorrect and misleading: "Dessler’s claim (and the IPCC party line) is that cloud changes are caused by temperature changes, and not the other way around. Causation only occurs in one direction, not the other." No, Dessler says no such thing. Dessler (and everyone except Spencer) is saying that ENSO causes temperature changes which lead to cloud changes which lead to feedback. Not *all* cloud changes, as Spencer is implying. He then measures that feedback. Spencer says no, this is wrong, the arrow of causation is backwards. He is more explicit in his reference to ENSO in his e-mail. "But what if the warming was caused by fewer clouds, rather than the fewer clouds being caused by warming? In other words, what if previous researchers have simply mixed up cause and effect when estimating cloud feedback?" Remember, we're speaking of ENSO. This is why Dessler asked Spencer explicitly about it. Spencer's answer is there for all to see. "What we demonstrated in our JGR paper earlier this year is that when cloud changes cause temperature changes, it gives the illusion of positive cloud feedback – even if strongly negative cloud feedback is really operating!" This can not be relevant to Dessler's measuring of cloud changes and feedback during ENSO *unless* Spencer believes that cloud changes are causing ENSO. Again, he's been asked explicitly by Dessler, and he has answered explicitly. "It doesn’t mean that “clouds cause El Nino”, as Dessler suggests we are claiming, which would be too simplistic..." "too simplistic" doesn't mean "wrong", HR. Spencer does some handwaving to try to convince people he's not saying something quite as stupid as "cloud changes cause ENSO", but remove the handwaving, and that's all he's got. As his e-mails to Dessler make clear. HR: "Albatross this is again getting away from the science, I should have ignored NewYorkJ and dhogaza's lead. There is actually lots of science in both authors papers that is being ignored by this narrow focus. Hopefully you'll ignore this post and focus on what I raised earlier." Sorry. ENSO-is-forced-by-cloud-changes is an epic fail too great to be ignored. Spencer's claim has to be true, because if not, then the "illusion of positive cloud feedback" is false and his argument implodes. In the physical world, you can't ignore the arrow of causality, and as Dessler makes clear, no one other than Spencer believes that ENSO is caused by cloud changes. Flip the arrow of causality in the direction that every other than Spencer accepts, then his "negative feedbacks replace the illusion of positive feedbacks" goes away. "There is actually lots of science in both authors papers..." And Dessler acknowledges this, and makes clear that Spencer's done some interesting things, if you ignore his claims regarding what causes ENSO. And Spencer? Does he acknowledge that there's lots of science in both papers, i.e. in Dessler's? No, he calls a press conference to claim that it's bogus and writes a blog post claiming it's a "step back for science". Actually, that negative step is really an illusion and in reality it's a step forward ...
  39. An Even Cloudier Outlook for Low Climate Sensitivity
    100 e I agree with you Spencer is saying (some) temperature change is initiated by clouds not that ENSO is initiated by clouds. 102 dhogaza I read the email exchange, I don't see where he says or infers "ENSO are caused by clouds". Please reproduce the quote here so I can find it in the emails. 96 Stephen Baines Stephen you fail to mention deltaT here and it seems to be the relationship between clouds and deltaT that Spencer is arguing over not ENSO. I think when it comes to "initiators" and "feedback" it's the relationship to deltaT that Spencer is concerned about. Anybody want to move on from this and talk about phase space plots?
  40. An Even Cloudier Outlook for Low Climate Sensitivity
    97 Albatross I'm not questioning the sincerity of Dessler, I'm not trying to look for angels and devils in the process. I think the reader at RC is lead down that particular path by the paragraphs following the "ENSO are caused by clouds" statement, I'm not suggesting that Dessler is consciously trying to lead us there but that is what is happening. It's difficult to know where to take this particular arguement when Spencer has explicitly stated on his blog that he does not support the idea that ENSO are caused by clouds. Albatross this is again getting away from the science, I should have ignored NewYorkJ and dhogaza's lead. There is actually lots of science in both authors papers that is being ignored by this narrow focus. Hopefully you'll ignore this post and focus on what I raised earlier.
  41. An Even Cloudier Outlook for Low Climate Sensitivity
    HR: "These are Spencer's words, not Dessler's interpretation of Spencer's words. " Uh, his e-mail messages are his words, too, and Dessler presents them verbatim so we can interpret them ourselves. It is clear that Spencer's claiming that scientists have the arrow backwards regarding clouds and ENSO. He says so directly.
  42. An Even Cloudier Outlook for Low Climate Sensitivity
    88 Albatross and Riccardo It looks like in Spencer's Fig1 that he actually takes Dessler's approach to calculating radiative forcing. He uses different data sets but the methodology is the same. In that figure he seems to show that depending on exactly which data set you use (HADCRUT or satellite for temp) and how you handle the data (different averaging periods) you can get very big differences in the radiative forcing estimate (0-2.5 W m-2 K-1). I guess Dessler would counter that he shows robustness by using two data sets of his own and getting similar results. Any greater merit in either authors approach? Maybe this is not actually getting to the point of disagreement between Spencer and Dessler anyway. The curious thing is using Desslers method Spencer actually gets very similar results to Dessler only with much greater range (Spencer 0 - 2.5 and Dessler -0.2 - 1.3). The point both you (and Dessler) seem to want to emphasise could still be made with Spencer's result, that is using this method there is no evidence of large negative feedback. From what I can see though Spencer's issue isn't just about the robustness of the method but whether Dessler's method is valid at all. Even for Spencer that is not answered by the confidence in the stats but by using a different method, phase space plots. I guess what we should be focussing on is whether phase space plots are giving us the added information that shows that Dessler (and others) method for estimating feedback is invalid.
  43. An Even Cloudier Outlook for Low Climate Sensitivity
    HR @94, It sounds to me like Spencer is just nitpicking semantics. Temperature change is one of the chief characteristics of ENSO, and Spencer is clearly arguing that this temperature change is initiated by clouds. That view is indeed outside of the mainstream.
  44. An Even Cloudier Outlook for Low Climate Sensitivity
    This is somewhat OT but related to climate sensitivity. Remember the news last week about the NASA study showing negative feedbacks from plants that bring climate sensitivity down to 1.64C? Potholer54 on youtube has done a great video debunking that myth. If you haven't heard of Potholer54 for before (aka journalist Peter Hadfield) definitely check out his other videos. He's the kind of quality journalist this world is severely lacking these days.
  45. Human CO2 is a tiny % of CO2 emissions
    #92: "more importantly nothing to indicate distance. The arrows in the figure suggest vary large distances " These are schematics of the flow of materials in a dynamic system. There is no distance scale involved. This type of figure is the standard, in use for decades; for example, see figure 10 in Post et al 1990. "would like to have people acknowledg or refute my assertion that the figure is bad science" An assertion that this is 'bad science' needs some substantiation. There are far more egregious example of bad science to be found on a routine basis in the denialist sources.
  46. An Even Cloudier Outlook for Low Climate Sensitivity
    Stephen @96, Interesting perspective and insights. Of course another possibility is that Spencer let the "truth" slip in his exchange with Dessler (i.e., let slip his true feelings on the issue).
  47. An Even Cloudier Outlook for Low Climate Sensitivity
    HR, I think that you might also be going off on a "flight of fancy" when you suggest "The power of that argument is to place Spencer so far outside the mainstream as to discredit everything he says". I would argue that Spencer's behavior and comments in recent years (many of which were made on his own blog) are in fact doing just that (i.e., discrediting him). Dessler strikes me as a sincere person who is not likely to engage in the tactics that you are accusing him of. Also, I do not see Dessler et al. holding a press conference the very minute a "skeptic" paper is officially released in order to try and sabotage it. It is Spencer who is playing games, not Dessler. The logic of the contentious statement that Spencer made in his email definitely suggests that for the 2007-2008 La Nina, changes in clouds preceded changes in temperature. Now in Spencer's defense, it was an email, which is a horrible medium for communicating sometimes. Maybe he was simply not clear or mis-spoke. What I do not understand is why Spencer has not spoken up to clarify his position since Dessler made his post at RC, or why he did not take the opportunity to discuss the matter further by email with Dessler. This whole ENSO fiasco is just a distraction though. Dessler's main points are that the cloud feedback in response to warming is very likely positive and that the models are doing a pretty good job in reproducing this short-term (positive) feedback. Anyone still trying to claim that climate sensitivity is low, is on incredibly thin ice-- some might even go so far as to say that they are already flailing in the water.
  48. An Even Cloudier Outlook for Low Climate Sensitivity
    The question HR is why does he clearly hold one view when talking to Dessler and another when blogging to the public. The point that Dessler is making in the emails is that if ENSO is initiated by ocean-atmosphere interactions, and if this leads to cloud formation that reinforce that change, then that is a feedback. It is the magnitude of that very feedback that Dessler is trying to measure. When confronted with that reasoning in the emails, Spencer argues that the clouds initiate ENSO by affecting surface temp so as to avoid admitting that clouds are acting as feedbacks. In the quote you provide above from his site, he seems to be talking about clouds as a feedback mechanism, which essentially means Dessler is correct in his approach. He seems to realize (and take advantage of)the fact that he is talking to an audience who is not aware of the important distinction between clouds as initiators and clouds as feedback mechanism, and therefore who won't realize that he is backing into a corner.
  49. An Even Cloudier Outlook for Low Climate Sensitivity
    To put it simply I think Dessler thinks A) ENSO causes temperature change which causes cloud changes which cause further temperature changes. A classic feedback situation While Spencer is proposing some role for B) ENSO causes circulation changes which cause cloud changes which causes temperature changes. Unforced internal variability I'm not sure Spencer is proposing the first one does not exist just that what is showing up in the data set is a mixture of both. It's this that makes Desslers (and others) methodologies different from Spencer's. Anyway I'll post this on Spencer's blog to see what he has to say.
  50. An Even Cloudier Outlook for Low Climate Sensitivity
    91 NewYorkJ 93 dhogaza You could also try this on Spencer's blog I'll even copy the relevent bit for you "To Dessler’s credit, he actually references our paper. But he then immediately discounts our interpretation of the satellite data. Why? Because, as he claims, (1) most of the climate variability during the satellite period of record (2000 to 2010) was due to El Nino and La Nina (which is largely true), and (2) no researcher has ever claimed that El Nino or La Nina are caused by clouds. This simple, blanket claim was then intended to negate all of the evidence we published. But this is not what we were claiming, nor is it a necessary condition for our interpretation to be correct. El Nino and La Nina represent a temporary change in the way the coupled atmospheric-ocean circulation system operates. And any change in the atmospheric circulation can cause a change in cloud cover, which can in turn cause a change in ocean temperatures. We even showed this behavior for the major La Nina cooling event of 2007-08 in our paper! It doesn’t mean that “clouds cause El Nino”, as Dessler suggests we are claiming, which would be too simplistic and misleading of a statement. Clouds are complicated beasts, and climate researchers ignore that complexity at their peril." These are Spencer's words, not Dessler's interpretation of Spencer's words. It can't be any clearer that he does not hold the view that Dessler assigns him. I understand what Spencer is saying here and I'm not a climate scientist. He's not arguing clouds cause ENSO, he's questioning the assumptions about the relationship between clouds and temperature. In Spencer's first email he says clouds proceed temperature, not clouds proceed ENSO. It's Dessler that seems to think that this means ENSO is caused by clouds. My reading of Spencer's work is to try to understand what he calls "internal radiative forcing" and other's call "unforced internal variability". This isn't just his theory, what's novel about Spencer's work seems to be in the understanding of how these processes affect the measurement of short term radiative forcing. While Spencer goes off on a flight of fancy about the timing of the publication, and should really hold his head in shame over that, I do think he has a point about Dessler's use of the "clouds cause ENSO" arguement. The power of that arguement is to place Spencer so far outside the mainstream as to discredit everything he says. It's no more worthy a tactic than Spencer's conspiracy theory and no better at discrediting the science.

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