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Comments 86101 to 86150:

86101. DSL at 12:11 PM on 11 May 2011
       It's the sun
       For me, it's just a simple way of showing that TSI and Temp have come completely unhinged in the last 35 years.
86102. AndrewMF at 11:53 AM on 11 May 2011
       It's the sun
       Hi. First Post, please be nice :) Can someone (anyone?) explain why in this graph we are comparing TSI Actuals against Temperature Anomalies? I've done a (very little) bit of stats and one thing I remember is that if you want to compare things you have to get those things onto the same playing field. On the whole, SkS does a great job helping me to understand what's going on. Sometimes (like this for example) I'm left wondering why the author didn't do the proper job... Thanks.
       Moderator Response: Using the anomaly instead of the raw temperature merely is a good way of reducing noise. An example of another way of reducing noise is to smooth a curve with a moving average. The anomaly still addresses our question: Does temperature change across time correlate with TSI? Temperature anomaly change mirrors raw temperature change. Think about what the raw temperature curve would look like next to the anomaly curve. A very rough analogy: It doesn't matter whether you plot the temperature in degrees Farenheit or degrees Celsius, if what you are interested in is the shape of the curve across time.
86103. Eric (skeptic) at 11:22 AM on 11 May 2011
       CO2 has a short residence time
       drrocket, welcome back to the thread! I disagree with your item 1, that the IPCC is claiming different ocean uptake rates for NCO2 and ACO2. There is a slight isotope preference for vegetation uptake, but that is mostly cyclical (the same isotope ratios are released after the vegetation dies in the NH fall). Someone else will have to address your other items, but certainly item 7 (CO2 is well mixed) has much more evidence than you imply, in particular your item 10 which is verifiably true, not just a claim derived from your preceding items. Your denouement, "claim" 12, is one I might also argue with, but I would certainly consider more evidence than the single claim of thermodynamic equilibrium at the ocean surface. Are trying to prove your claim that CO2 rises are due to a warming ocean? If so, you still haven't addressed the point that net CO2 uptake can be positive in a warming ocean. That cannot be disproven by using local thermodynamic equilibria since those need to be integrated to determine the net effect. You certainly cannot use global average T, P, and other parameters to do this.
86104. Ken Lambert at 11:02 AM on 11 May 2011
       Lindzen Illusion #3 and Christy Crock #5: Opposing Climate Solutions
       Quite right scaddenup. I need to update my terminology for the renewables. In the 24/7 industry 'availability' and 'capacity factor' mean the same thing. When you fire up a 500MW turbine - you usually get 500MW at full load unless the builder has sold you a crock. The output and installed capacity are the same. Outages for maintenance reduce the 'availability' of the installed capacity - and reduced load running drops the effective capacity factor. This is to be avoided with baseload plant by load matching and topping with gas turbines, pumped storage etc. The big difference between base load plant and renewables is that short of an earthquake or tsunami, outages and disruptions to output are controllable (even programmable)with base load, but subject to weather and cloud cover with PV Solar and Wind. Storage devices are essential to make these viable base load supplies. The question is - what are the numbers when storage devices are added to the cost of PV Solar and Wind.
86105. dhogaza at 10:42 AM on 11 May 2011
       Lindzen Illusion #6: Importance of Greenhouse Gases
       Camburn ... dude ... it's a many pizza boxes model ...
86106. Tom Curtis at 10:20 AM on 11 May 2011
       Lindzen Illusion #6: Importance of Greenhouse Gases
       Camburn @41, what "a slab can have many cross sections" even means in this discussion I am unsure. What I am sure of is that "slab atmosphere" has a very definite meaning in climate modelling, and using that meaning, your statements are false. You may, like Humpty-Dumpty decide that your words shall mean exactly what you mean them to, but having gone the route of idiosyncratic language you have decided that you don't want to communicate, nor reason accurately. @40 As Dana points out, you are wrong about the water vapour feedback. What is more, the difference between the effective temperature of the Earth, and the surface temperature is known; and the consequent difference in power also. It follows that if one factor contributing to the difference between the two is less than is thought, then the other factors must be greater to compensate. If the water vapour feedback is negative, in other words, then CO2 forcing must be stronger.
86107. RobertS at 09:54 AM on 11 May 2011
       Lindzen Illusion #6: Importance of Greenhouse Gases
       "For some reason you don't like the word slab....which why you don't is beyond me." It has nothing to do with liking or not liking; it's about correct terminology. As Tom so patiently explained, a slab atmosphere model can have more than one layer, but in any case, it treats each layer as isothermal and homogeneously mixed, with uniform broadband absorptivity over the entire SW and LW spectrums (typically a_SW=0, a_LW=1). All energy flow is purely radiative, and the planet is treated as a uniform radiating sphere. You cannot calculate the radiative contribution of each LW absorber properly using this method, and that's not what Schmidt et al. do. Nowhere in your link does it state that any model of the climate system is a slab model if "the climate is held fixed" (as defined by Schmidt et al.) because a slab atmosphere is a specific [and overly simplistic] representation of atmospheric energy flow, nowhere near the complexity used in GCMs. Anyway, this conversation is off topic and more than a little silly.
86108. dana1981 at 09:34 AM on 11 May 2011
       Lindzen Illusion #6: Importance of Greenhouse Gases
       Camburn #40 -

       "I will not endorse Lacis etal in intirety. They are assuming that h20 vapor is only a positive feedback. I am not ready to assume that. Schmidt also assumed that. Dressler showed that it could be negative"

       This is doubly wrong. First off, Lacis and Schmidt didn't "assume", they modeled. Secondly, the water vapor feedback is positive. It's the cloud feedback that Dessler concluded could be slightly negative.
86109. Camburn at 09:23 AM on 11 May 2011
       Lindzen Illusion #6: Importance of Greenhouse Gases
       Tom@39: You are totally wrong in your assesment. A slab can have many cross sections. Think what you may....I don't really care. I made an observation as to the usefullness of this paper in a chaotic climate, which is what we live in. For some reason you don't like the word slab....which why you don't is beyond me. Do a search for other posts I have made on this site, then formulate your opinion. Thanks in advance.
86110. Camburn at 09:17 AM on 11 May 2011
       Lindzen Illusion #6: Importance of Greenhouse Gases
       Tom@38: I will not endorse Lacis etal in intirety. They are assuming that h20 vapor is only a positive feedback. I am not ready to assume that. Schmidt also assumed that. Dressler showed that it could be negative, so that option must remain open as a consideration, which would change the results of both Lacis and Schmidt.
86111. Tom Curtis at 09:11 AM on 11 May 2011
       Lindzen Illusion #6: Importance of Greenhouse Gases
       Sphaerica @37, it is not true that every model is a slab model in that: Slab models allow for no lateral energy transfers; and Slab models do not allow for convective or latent heat transfers. I know you are being generous to Camburn by allowing as much truth to his argument as you can without absurdity, but you have, I believe allowed too much to avoid confusion. Further, Camburn's defence in terms of multiple slabs is not warranted. His original claim was of a slab atmosphere. Singular. Had he said "it's just a twenty slab atmosphere" he would still have been incorrect for reasons given above, but it would have punctured his rhetoric of suggesting absurd oversimplification. So he suggested slab (singular) for rhetorical effect, and only allows for multiple slabs later to pretend he is being reasonable.
86112. Tom Curtis at 09:02 AM on 11 May 2011
       Lindzen Illusion #6: Importance of Greenhouse Gases
       Camburn @33, 1) As pointed out by Sphaerica, RobertS, and KR, your definition of a slab model is false. Even allowing for a two slab model, or a twenty three slab model, a slab model only models radiative transfers. Further, a slab model treats the entire surface of the Earth as being isothermal, and homogenous, and does the same for each "slab" of atmosphere it incorporates. IN contrast a Global Circulation Model models heat transfers by convection, advection and latent heat. It divides the world up into cells which have different surface properties. It models heat transfers by any means between each layer, and between adjacent cells at each layer. As a result, a GCM will automatically generate the major atmospheric circulations including Hadley cells, Ferel cells and Polar cells with associated trade winds, westerlies and doldrums. It will also generate internal representations of clouds and precipitation automatically. Describing a GCM as a slab model shows complete ignorance of the subject, and renders your comment irrelevant. 2) Schmidt et al did not hold "all variables" constant. He held "... the climate (spatial and temporal distributions of temperature, surface properties, etc.) fixed". (My emphasis.) That means when varying CO2 levels, he did not allow water vapour content to fall. But the temperature was not held constant, rather it was held to the annual cycle of temperatures at each particular location and altitude. Likewise with water vapour content and cloud cover when they were not being explicitly varied. That is not a "static mode". If your understanding of the experiment where correct, Schmidt et al would only have modelled the changes to radiative forcing at a particular temperature at a particular location. But as it stands, they modelled the change over a range of temperatures across all seasons and across all locations in the globe. As such, it usefully determines the radiative forcings of the atmospheres components across the normal range of conditions we face. You are right, of course, that that exercise is not entirely useful. Far more useful is to allow temperatures to vary with changing atmospheric concentrations, and to allow water vapour and cloud levels to vary with temperature. Given your qualms about Schmidt et al, you will no doubt endorse Lacis et al who do exactly that. So, assuming you are truly a sceptic and not just a denier, you would agree that without CO2 in the atmosphere, the water vapour concentration of the atmosphere would plummet, and the Mean Global Surface Temperature drop by around 34 degrees C.
86113. drrocket at 08:43 AM on 11 May 2011
       CO2 has a short residence time
       Eric (skeptic), 7:01 AM, 2/16/11, CO2 has a short residence time This thread, CO2 has a short residence time updated 6/26/10, and the Seawater Equilibria thread of 1/10/11, are companion pieces. The first debunks IPCC's elementary formula for the physics of residence time to make room for complex ocean equilibrium theory IPCC applies to the ever-changing surface layer of the ocean. You appeal to this theory for the proposition that a warming ocean can be a net sink of CO2. IPCC uses it instead to create a model in which all of the following hold: (Claim 1) Natural CO2 is far more soluble than anthropogenic CO2, so the ocean absorbs 100% of the ~90 Gtons/yr of nCO2 from the ocean, but only half the ~8 Gtons/yr of ACO2; (Claim 2) Henry's Law coefficients differ between the isotopes of CO2 so that it separates (fractionates between) nCO2 from ACO2; (Claim 3) Henry's Law coefficient for ACO2 in water no longer depends on the established parameters of temperature, pressure, and salinity, but dominantly on the equilibrium chemical state of carbonates in the water; (Claim 4) Adding CO2 acidifies the surface layer of the ocean; (Claim 5) The rate of ACO2 dissolution depends on the rate of sequestration of CO2 through the organic pump and the calcium carbonate counter pump; (Claim 6) Thus ACO2 is long-lived in the atmosphere, with a residence time measured in decades to centuries instead of a few years according to the IPCC formula; (Claim 7) Therefore CO2 is well-mixed in the atmosphere; (Claim 8) Hence MLO CO2 measurements are global, not regional; (Claim 9) Therefore calibrating CO2 concentrations from all measuring stations to comport with MLO is valid; (Claim 10) All the calibrated CO2 measurements over the globe agree, validating that the MLO record is global; (Claim 11) Therefore the bulge in CO2 measured at MLO over the last half century is man made; (Claim 12) Therefore the coincidental global temperature rise over the last half century is anthropogenic. All these claims flow from the assumption that the surface layer is in thermodynamic equilibrium. Seawater Equilibria by hfranzen begins, The audience for whom this piece is intended consists of people who know some chemistry and are uncertain about how to consider the often made claim by deniers that the oceans contain so much dissolved carbon that human production is inconsequential. It then undertakes a derivation that includes this line: Algebra then yields the molalities of the remaining solute species at 288K, specifically the equilibrium molalities of CO2(aq), HCO3^-(aq) and CO3^2-(aq), as well as the other species, are determined for the average ocean. This is IPCC's Fatal Error #3. IPDD's Fatal Errors. IPCC uses the same stoichiometric equations as hfranzen (AR4, Box 7.3, p. 529), sourced to Zeebe and Wolf-Gladrow, 2001 (science for sale, Amazon, $94.34) (AR4, ¶7.3.4.1, p. 528). The latter shows that the solution to the equations using the stoichiometric equilibrium constants is given by the Bjerrrum plot. Reported in Wolf-Gladrow, D., CO2 in Seawater: Equilibrium, Kinetics, Isotopes, 6/24/06, chart 5. IPCC refers to a single point from the Bjerrum plot without ever mentioning it by name. However, the same two authors specify that these equations apply not in some vague equilibrium state, but In thermodynamic equilibrium. Bold added, Zeebe, R. E., & D. A. Wolf-Gladrow, Carbon dioxide, dissolved (ocean). Encyclopedia of Paleoclimatology and Ancient Environments, Ed. V. Gornitz, Kluwer Academic Publishers, Earth Science Series, in press 2008, p. 1. The surface layer is not in mechanical equilibrium, nor in chemical equilibrium, nor in thermal equilibrium, so it fails all three stringent requirements to be in thermodynamic equilibrium. Thermodynamic equilibrium means neither dynamic equilibrium nor steady state, as AGW proponents argue from time to time. Chemists evaluate equilibrium constants only at equilibrium. For example, here's a piece of from a UK workbook instructions for 16- to 19-year-old students on how to prepare samples for measuring equilibrium constants: Keep the bottles at 50 °C for about twenty minutes, shaking them frequently; then let them stand at room temperature overnight. Nuffield Physical Science workbook, Section 6 Chemical equilibrium, p. 340. Le Chatelier's Principle (p. 300) and the Equilibrium Law (p. 299) also apply. Id.. The Principle is If a system at equilibrium is disturbed by a change in temperature, pressure, or the concentration of one of the components, the system will shift its equilibrium position so as to counteract the effect of the disturbance. Le Chatelier's Principle (1888). Chem 002, Lecture VIII. The Law states that equilibrium coefficients are approximately constant at a given temperature. But nothing can be said about the state parameters, temperature (T), pressure (P) and reactant concentrations ({U_i}), of a system not in equilibrium. If the non-equilibrium (or disequilibrium) trajectory a system follows between equilibrium states could be quantified and predicted, Le Chatelier's state-of-the-art Principle, which only applies to the end points of the trajectory, would be obsolete. Because the state of a system is a vector in (T, P, {U_i}), the state cannot be ordered. No law analogous to the Equilibrium Law exists to provide a direction or bounds on concentrations in disequilibrium. As a result, and notwithstanding that the pH of the surface is known, the molalities of the carbonate system are unknown in the real ocean. The article's reference to the average ocean and IPCC's claim that the ratio of CO2:HCO3^-:CO3^2- in the surface layer is approximately 1:100:10 (AR4, Box 7.3, p. 529) are both meaningless. IPCC models the atmosphere as a buffer holding excess CO2 (actually ACO2) in order to create sufficient absorption to warm the climate. Instead, the surface layer should be recognized as the buffer holding excess CO2 in the unknown ratio of x:y:z with HCO3^- and CO3^2- so that dissolution can obey Henry's Law, and to supply ionized CO2 in solution for the biological pumps. (IPCC diagrams the pumps incorrectly as reacting with molecular CO2 in the air. AR4, Figure 7.10, p. 530.) With the principles of equilibrium honored, the laws of chemistry and physics can all be satisfied. The article attempts to disprove a straw man claim that human production [of CO2] is inconsequential with false science. In fact, for other reasons it is true The audience for whom hfranzen's piece is intended is no more knowledgeable than IPCC's Policymakers. It consists of people who nothing about equilibrium, much less equilibrium chemistry, or physics, and who accept IPCC's model, with all its false claims, as demonstrated by authority.
86114. Bob Lacatena at 08:42 AM on 11 May 2011
       Lindzen Illusion #6: Importance of Greenhouse Gases
       33, Camburn, I did look at the entire thing. The page that is confusing you is where it says "Earlier, we developed a ‘two layer’ model of a slab atmosphere:" What it means is that it treated each layer as a slab (i.e. it used the slab approach, but with two of them instead of one). This is quite common, and ultimate any model -- even one with 1,000 layers -- is in this way a "slab atmosphere." In any event, as I already posted, Schmidt did not use a slab atmosphere. The model was horizontally gridded with either 90x35 = 3150 cells, or 180x70 = 12,600 cells. This in turn is divided into 20 layers, for either 63,000 or 252,000 individual, 3-dimensional cells. Hardly a slab.

       It is not a dirty word.

       Then why do you use it disparagingly?

       It only means that the composition of all variables are kept constant, which he certainly indicates in his paper. He then changes one variable to obtain a result.

       No it doesn't, and no he didn't. Did you bother to read my explanation about this? First, "slab" has nothing whatsoever to do with setting up static parameters. Second, ou are very, very confused about how models are structured, how they are used, and what was done in this case. Let me try again. They ran the complex, global climate model, which has been under development for decades, and takes weeks to months on a very high powered computer to run for anywhere near reasonable time scales. It involves physics and physical interactions of complex atmospheric makeup, radiation, ocean, and what-not, in a grid containing 252,000 individual cells. They ran this to achieve a state which represents the 1980 climate (or, more likely, several states spread out over the course of one solar year) and at points froze the simulation to allow them to compute -- over 252,000 cells (slabs, if you prefer) -- the radiative fluxes. From the paper:

       The climatology is derived from a yearlong simulation using ca. 1980 conditions (CO2 concentrations are 339 ppmv, etc., as described by Schmidt et al. [2006]) and each experiment consists of a year’s simulation with a transient but noninteractive climate.

       Your presumption that the model was somehow initialized (other than starting parameters to simulate 1980 conditions) hand artificially held constant (other than for the purposes of being able to extract the necessary numbers and perform the desired calculations) is mistaken.
86115. Albatross at 08:41 AM on 11 May 2011
       Lindzen Illusion #6: Importance of Greenhouse Gases
       Just to let everyone know, Dr. Betts (post @21) has published extensively and is a widely cited and much respected scientist. We are very fortunate to have him here. Thank you for dropping by Dr. Betts.
86116. Camburn at 08:39 AM on 11 May 2011
       Lindzen Illusion #6: Importance of Greenhouse Gases
       KR: I didn't want to argue over the deffinition of slab at all.
86117. scaddenp at 08:09 AM on 11 May 2011
       Lindzen Illusion #3 and Christy Crock #5: Opposing Climate Solutions
       I'd also agree that PV is niche at moment. Too expensive. I'd say West Island should be looking at new gen nuclear and SCP. Plenty of resource in both but both really nascent and far more worthy of subsidy to the get started than FF. (Though I am anti-subsidy on anything except scientific research, healthcare and education).
86118. julienx2k2 at 07:46 AM on 11 May 2011
       Crux of a Core, Part 3... Dr. Ole Humlum
       Humlum has striken again this week... Using Fig. 1 without even changing anything, in a full page article in a weekly newspaper for Engineers (Teknisk Ukeblad). Given that you shared your comments with him and he didn't even took them into account in his latest achievement (I wish you could read it, it is worth it, full of classical denier's arguments), Bjarne is right, Humlum is a real denier.
86119. KR at 07:32 AM on 11 May 2011
       Lindzen Illusion #6: Importance of Greenhouse Gases
       Camburn - Just to clarify, the term "slab model" is often used to describe a single-layer atmospheric model, which is really too simple for detailed answers. I would suggest describing the "fixed" parameters, assuming that any serious modelling will be using a 20+ layer atmospheric model, rather than just arguing over a side definition.
86120. Camburn at 07:19 AM on 11 May 2011
       Lindzen Illusion #6: Importance of Greenhouse Gases
       Sphaerica @32: Please read the total link. There is a two layer model of a slab atmosphere. There is nothing wrong with a slab atmosphere as a tool. Schmidt gets results by using a slab atmosphere. It is not a dirty word. It only means that the composition of all variables are kept constant, which he certainly indicates in his paper. He then changes one variable to obtain a result. Is this a pre-concieved result? I wouldn't have a clue as I didn't run the model. My initial response was to the usefullness of this run. Being it was run in a static mode, (Is that less offensive?).....the application to climate is minimal because any change in composition in the real world results in various changes in climate as a whole.
86121. scaddenp at 07:10 AM on 11 May 2011
       Lindzen Illusion #3 and Christy Crock #5: Opposing Climate Solutions
       Ken, fair enough but you said, Victoria was 12.5% availability, not capacity.
86122. Bob Lacatena at 06:33 AM on 11 May 2011
       Lindzen Illusion #6: Importance of Greenhouse Gases
       26, Camburn, I see nothing unusual about the reference to a slab atmosphere in the document provided. It in no way supports your own defition. Beyond this, GISS modelE consist of 20 layers, not one single "slab." Beyond this, that slab is further subdivided into a rather extensive grid:

       The model has a Cartesian gridpoint formulation for all quantities. Available horizontal resolutions are 4° X 5° and 2° X 2.5° latitude by longitude (and 8° X 10° for historical and pedagogical reasons). The effective resolution for tracer transport is significantly greater than these nominal resolutions because of the nine higher- order moments that are carried along with the mean tracer values in each grid box (see section 3d).

       In this context, your dismissive "slab" comments are meaningless. Separate from this, your confusion with a "slab" holding parameters constant is unfortunate, but the confusion is yours. Again, reconsider how the model works. It has a large number of variables, that work in concert while it is running, each affecting and being affected by others. But the output of the model is not necessarily the value being hunted in this particular scenario. So the model is allowed to run and achieve an equilibrium state, and then with all other values fixed it is possible to compute the radiative fluxes, almost as if time were frozen for an instant, to be able to measure everything instantaneously, and in an abstract way defeat the Heisenberg Uncertainty Principle. There is nothing whatsoever wrong with this approach. You are falsely applying sinister motives and techniques, as if they first set the model to provide the expected output, and then arrived at the desired result. This is simply not the case.
86123. dana1981 at 06:24 AM on 11 May 2011
       Lindzen Illusion #6: Importance of Greenhouse Gases
       akbetts' link is a very interesting read. When asked why he thinks water vapor/clouds are a negative feedback (page 71), he brings up his favorite "Earth hasn't warmed as much as expected" argument (Lindzen Illusion #1). He's got this whole house of cards built on false claims which are contradicted by observational evidence. More on that in Lindzen Illusion #7 later this week. It was also refreshing to read Gore's statements and questions. He actually had a solid understanding of climate science and desire to learn from the expert testimony. A stark contrast to today's congressional climate hearings, where politicians are just trying to score points, and Republicans just try to jam as many myths as possible into their alotted time.
86124. RobertS at 06:16 AM on 11 May 2011
       Lindzen Illusion #6: Importance of Greenhouse Gases
       Camburn @26, Your link doesn't support your definition.
86125. Camburn at 06:16 AM on 11 May 2011
       Lindzen Illusion #6: Importance of Greenhouse Gases
       Robert: Your post appeared after I posted so I will reply. From what I have read, and my understanding, a slab is considered a stationary fix of the atmosphere. There can be many cross sections of the slab. Hence my reference to a CT scan. By holding all climate paramiters stable, it is a fixed slab of atmosphere. Anyways..That is my take.
86126. Camburn at 06:12 AM on 11 May 2011
       Lindzen Illusion #6: Importance of Greenhouse Gases
       I won't comment on the slab question again as it detracts from the jist of this topic. I made an observation that was written in the paper. He held the climate paramiters stable, which only happens in a slab. His slab went from the surfact to TOA. If he had run the model without those paramiters, it would not be a slab as it would change each micro second and become a much more complex analysis.
86127. RobertS at 06:12 AM on 11 May 2011
       Lindzen Illusion #6: Importance of Greenhouse Gases
       "What you are quoting is a partial slab. When Schmidt stated that the climate paramiters were fixed....that is the definition of a slab atmosphere in entirety." I've never heard of this definition -- it differs so very much from the "partial" definition used in simplified energy balance models. Perhaps you can dig up a reference?
86128. Camburn at 06:07 AM on 11 May 2011
       Lindzen Illusion #6: Importance of Greenhouse Gases
       As to what a slab atmosphere is I will refer you to this: http://www.gps.caltech.edu/classes/ese148a/lecture8.pdf
86129. David Horton at 05:56 AM on 11 May 2011
       Upcoming 'Climate Change Denial' book launches in Sydney and Canberra
       John, will try to make the Canberra launch. Well done.
86130. dana1981 at 05:56 AM on 11 May 2011
       Lindzen Illusion #6: Importance of Greenhouse Gases
       akbetts - interesting, thanks for the info. At least as late as 1996 Lindzen was still arguing that climate models exaggerated the water vapor feedback, as discussed in Lindzen Illusion #4.
86131. Bob Lacatena at 05:55 AM on 11 May 2011
       Lindzen Illusion #6: Importance of Greenhouse Gases
       23, Camburn,

       That is the definition of a slab atmosphere in entirety.

       This is wrong. If you believe it is correct, please provide a citation. See my comment at 20 to understand why certain parameters are held constant.

       He used AR4 GISS E and and fixed the climate.

       No. He presumably ran the model to arrive at a representative state at equilibrium, then held that state constant while computing the radiative fluxes of the various components. He did not "restrain" the model by parameters it was "subjected to." There is a huge difference. You misunderstand what was done.
86132. Camburn at 05:46 AM on 11 May 2011
       Lindzen Illusion #6: Importance of Greenhouse Gases
       Robert: What you are quoting is a partial slab. When Schmidt stated that the climate paramiters were fixed....that is the definition of a slab atmosphere in entirety. He used AR4 GISS E and fixed the climate. I don't understand the questions that have been raised as I stated what Schmidt stated about the model used. The model was restrained by the paramiters it was subjected to. Kinda like one slice of a CT scan isn't it?
86133. chuckbot at 05:28 AM on 11 May 2011
       Monckton Myth #16: Bizarro World Sea Level
       I'm still kind of reeling. http://cheezburger.com/View/4725366272
86134. RobertS at 05:28 AM on 11 May 2011
       Lindzen Illusion #6: Importance of Greenhouse Gases
       Camburn @17, How does that quote indicate a slab atmosphere? "Slab" is typically taken to mean a single isothermal layer with uniform absorptivities over the LW and SW spectrums. GISS ModelE certainly isn't that. Radiative forcing by definition is the change in radiative flux at the TOA considered whilst keeping the climate "fixed" (after stratospheric equilibration).
86135. akbetts at 05:20 AM on 11 May 2011
       Lindzen Illusion #6: Importance of Greenhouse Gases
       The October 7, 1991 testimony to the Senate Hearing before the Committee on Commerce, Science, and Transportation, United States Senate on "Global Change Research: Water Vapor and the Climate System" gives an informative perspective on the scientific perception of water vapor and cloud feedback issues in 1991. I have posted a full transcript of this hearing (which is otherwise unavailable on the web) at http://alanbetts.com/workspace/uploads/us-senate-roleofcloudsinclimate-7-1283380998.pdf This hearing, chaired by Senator Al Gore; including prepared statements by: Albert Arking, Alan K. Betts, Robert Cess, Robert Charlson, Michael Hall, Richard S. Lindzen, V. Ramanathan, William B. Rossow, Shelby Tilford, Col. Robert Townsend and Kevin Trenberth as well as the lengthy discussion that followed, which clarified several issues. This hearing is an interesting snapshot of scientific opinion on the climate change issue in 1991. Speakers were invited to present a range of opinions. I was invited to present a counter argument to the negative feedback mechanism (upper tropospheric drying by deep convective clouds in the tropics) proposed by Lindzen at that time. My prepared statement ("The Role of Clouds in Climate Change") is P33-37; Lindzen's is P14-20. The general discussion starts on P50. The discussion of Lindzen's hypothesis is mostly P64-76. Lindzen formally withdrew his hypothesis during the discussion (on P68 - this was news to Al Gore). However I don't think this retraction was well-publicized; and Lindzen has continued to suggest other mechanisms for low climate sensitivity - which are discussed elsewhere on this site.
       Response:

       [DB] Hot-linked URL.

86136. Bob Lacatena at 05:18 AM on 11 May 2011
       Lindzen Illusion #6: Importance of Greenhouse Gases
       18, Camburn,

       ...by holding the climate fixed, this is the definition of a slab atmosphere.

       No, by holding the climate fixed, they do not need to worry about the interaction of absorption and emission changing those properties, which change the absorption/emission, and so on, requiring a huge number of recursive calculations. Reducing degrees of freedom within a problem in order to simplify calculations (i.e to make them remotely doable) is a pretty standard practice in most fields, and one that does not equate to a "slab" atmosphere.
86137. Bob Lacatena at 05:15 AM on 11 May 2011
       Lindzen Illusion #6: Importance of Greenhouse Gases
       17, Camburn, How does that quote in any way imply that the model uses a "slab" atmosphere? From Schmidt et al [2006] describing modelE:

       The standard vertical resolution has 20 layers and a model top at 0.1 hPa (Fig. 1). Compared to pre- vious 12-layer versions (i.e., Hansen et al. 2002), the 20-layer code has 2 extra layers near the surface, 2 more in the lower stratosphere, and 4 extra layers above 10 hPa. We also describe a 23-layer version that better resolves the stratosphere and has a model top near the mesopause (0.002 hPa; Rind et al. 1999; Shindell et al. 1999).

86138. Camburn at 04:55 AM on 11 May 2011
       Lindzen Illusion #6: Importance of Greenhouse Gases
       Tom Curtis@11: Also, I don't know what you mean as a sound bite as it is clear that by holding the climate fixed, this is the definition of a slab atmosphere.
86139. Camburn at 04:02 AM on 11 May 2011
       Lindzen Illusion #6: Importance of Greenhouse Gases
       Tom Curtis @11: Ref 3. Modeling Experiements: (14). WE use the IPCC AR4 version of GISS ModelE to calculate the instanteous changes in radiative fluxes to changes in indivueal LW absorbers, while holding the climate (spatial and temporal distributinos of temperature, surface properties, etc) fixed. This is a slab atmosphere. Thank you.
86140. chris at 03:58 AM on 11 May 2011
       Frauenfeld, Knappenberger, and Michaels 2011: Obsolescence by Design?
       Tom, in response to your suggestion that the 4 station+NAO analysis might be poor in covering global Greenland melt, FKM would point you to their methods section in which they describe the optimisation of their model by comparison with the empirical (satellite-derived) data from 1979-2009. They say:

       ”Our Greenland melt reconstruction therefore focuses on the relationship between summer average temperatures from the available four coastal locations in southern Greenland and our standardized melt index. We determined that during 1979–2009, a combined (simple average) temperature for JJA (4-Temp) correlates well with annual total melt extent. Using other spatial or temporal combinations of the temperature data and melt extent does not produce stronger or more robust relationships." ....and later on: ..."We find that these two variables explain 65% of the year-to-year variance and 81% of the trend in total melt extent from 1979 to 2009 (Table 1).”

       However the year-on-year comparison of modelled and empirical melt (FKM2011, Figure 3; reproduced below), shows that the model fails to accommodate some fairly strong and identifiable features of forced variability. Figure 3. Residual ice melt extent index (observed minus model fitted values) for our 4‐Temp and NAO model (solid circles) and for the model using run‐off (open circles) [Hanna et al., 2008]. It's clear, especially, that NH or global temperature variability that is represented in empirical melt data is not captured in the model; e.g.: - the cold years 1985/1986 that have very cool temperature anomalies in the global record - the cooling post-Pinatubo (the large 1992 departure of the model from empirical data) - the 1998-El-Nino -the truly enormous 2000 (negative), 2002 (positive) and 2003 (negative) departures between the empirical and modelled data. - all melts between 2004-2007 inclusive are underestimated in the model. (not sure why they don't show 2008, 2009 empirical/model comparisons). What does this mean 1. It supports your assessment of the potential flaws of assessing Greenland melt using 4 station +NAO data. In fact FKM2011 agree with you:

       ” Overall, the residuals are very similar, but the 4 years with the greatest residuals using our model (1998, 2000, 2002, and 2003) are all reduced by more than half in the run‐off model (the effects of the inclusion of precipitation in the run‐off model are small). This result suggests that broader spatial patterns of temperature across Greenland that are not well captured by our southern coastal temperature composite can account for a proportion of the variance in annual ice melt extent not captured by our two‐variable model.”

       2. It's not a fundamental flaw in the paper. After all you're allowed to publish a comparison of empirical melt index with reconstructed melt using a model, and it doesn’t have to be perfect. 3. However, it reinforces the essential meaningless of the discussion of statistical significance in differences in the empirical 2007 (and 2010) melt data and early-mid 20th century modelled melt. In my opinion the referees should have insisted that statements about stat. signif. be removed at the very least from the abstract. The following statement is particularly naff, considering the massive uncertainty in the model for the 18th century data:

       ” However, there are 20 years during the reconstructed period (1784–1978) for which the 2007 ice extent value falls within the 95% confidence bounds and it thus cannot be considered to be statistically different. These years fall within 1786–1789 and 1923–1961.”

       The mess that inappropriate statements of statistical significance in differences between apples and oranges leads to can be seen in the interminable analysis of statistical significance of this data elsewhere which, however interesting from a stats point of view, effectively stalls the discussion of the more meaningful questions we should be addressing; e.g. has Greenland likely entered a period of unprecedented melt, and what is the prognosis going forward? Those questions require consideration of all of the relevant data, in this case the evidence for enhanced glacial retreat now compared to then (as in mspelto’s analyses), the evidence that Arctic temperatures are greater (and likely to continue to rise) now than during the period of apparently high melt mid-20th century, and so on. e.g. while a statistician would argue (and does!), that the likelihood that 2007 (or 2010) melt index is larger than any during the 1920-1960 period, is actually quite small based simply on the numbers and their variances, a knowledgeable scientist together with a statistician would probably come to a conclusion more like: "The melt indices for 2007 and 2010 are each larger than any previous value in the historical reconstruction. Although the large uncertainty in the reconstruction data allows for the possibility that mid 20th century Greenland melt might have been as large or greater than contemporary melt years, the evidence that (i) Arctic temperatures have surpassed those of the mid-20th century, and (ii) glacier recession was less pronounced then compared to the contemporary period, does not support this interpretation." (P.S: only first part of this post addressed to Tom; parts 2. and 3. are me extemporizing...)
86141. dana1981 at 03:43 AM on 11 May 2011
       Lindzen Illusion #5: Internal Variability
       KR -

       "I would really love to see a true skeptic argument against GHG driven global warming - one based on real-world data, with some theory behind it."

       We'll present Lindzen's alternative to AGW in Lindzen Illusion #7, coming in a few days. I can't say it's based on real-world data though, as the post will show.
86142. KR at 03:20 AM on 11 May 2011
       Lindzen Illusion #5: Internal Variability
       Albatross - Tamino has outdone himself this time. Simple enough that anyone can understand the data treatment, clear enough that even in dim light, under the worst conditions, after several stiff drinks, that it's still evident what's going on. Many skeptic arguments these days seem to consist of cherry picking and graphic presentation sins, primarily concerning the Ocean Heat Content (which is both one of the most important values and considered the easiest to disagree with). Personally I find this disappointing - same old same old. I would really love to see a true skeptic argument against GHG driven global warming - one based on real-world data, with some theory behind it. But these days I'm not holding my breath waiting.
86143. Albatross at 01:55 AM on 11 May 2011
       Lindzen Illusion #5: Internal Variability
       Tamino, has really outdone himself this time, totally eviscerating the BS (bad science) that the 'skeptics' are so fond of using to deceive. So simply, yet utterly devastating... All data below are 5-year averages to filter out most of the noise. Red line is the Lowess smooth of the original data. GISTEMP global surface air temperature anomalies Global sea level rise 0-700 m Oceanic Heat Content (Minimum?) Arctic sea-ice extent anomaly Atmospheric CO2 These are datasets that the 'skeptics' and deniers routinely try and manipulate, distort, cherry-pick and misrepresent in order to deceive and trick.
86144. Albatross at 01:38 AM on 11 May 2011
       Lindzen Illusion #5: Internal Variability
       Some thoughts on issues surrounding the Argo data by some eminent scientists-- caution, findings may upset "skeptics", contrarians and deniers of AGW. From Hansen et al. (2011), link provided below: "An alternative potentially accurate approach to measure Earth's energy imbalance is via changes in the ocean heat content, as has been argued for decades (Hansen et al., 1997) and as is now feasible with Argo data (Roemmich and Gilson, 2009; Von Schuckmann and Le Traon, 2011). This approach also has sampling and instrument calibration problems, but it has a fundamental advantage: it is based on absolute measurements of ocean temperature. As a result, the accuracy improves as the record length increases, and it is the average energy imbalance over years and decades that is of greatest interest.

The error estimated by von Schuckmann and Le Traon (2011) for ocean heat uptake in the upper 2000 m of the ocean, ± 0.1 W/m2 for the ocean area or ± 0.07 W/m2 for the planetary energy imbalance, does not include an estimate for any remaining systematic calibration errors that may exist. At least some such errors are likely to exist, so continuing efforts to test the data and improve calibrations are needed. The Argo program needs to be continued and expanded to achieve further improvement and minimization of error." Also, "A verdict is provided by the ocean heat uptake found by von Schuckmann and Le Traon (2011), 0.42 W/m2 for 2005-2010, averaged over the planet. Adding the small terms for heat uptake in the deeper ocean, warming of the ground and atmosphere, and melting of ice, the net planetary energy imbalance exceeded +0.5 W/m2 during the solar minimum.

This dominance of positive climate forcing during the solar minimum, and the consistency of the planet's energy imbalance with expectations based on estimated human-made climate forcing, together constitute a smoking gun, a fundamental verification that human-made climate forcing is the dominant forcing driving global climate change. Positive net forcing even during solar minimum assures that global warming will be continuing on decadal time scales." Go here for the Hansen et al. (2011) paper. Go here for the von Shuckmann and Le Traon (2011) paper. This is clearly yet another no win for Lindzen and Spencer. Shameful then that Lindzen insists on knowingly misleading the public, politicians and policy makers on the science.
86145. CBDunkerson at 01:35 AM on 11 May 2011
       Lindzen Illusion #5: Internal Variability
       Even setting aside the ridiculous cherry picking involved in 'data since 2003'... that time period is clearly irrelevant when examining claims that the sharp increase in global air temperatures over the 20th century was caused by 'internal variability'. Heck, it isn't even a valid argument for a claim that 'atmospheric warming since 2003 has been caused by internal variability'... because both do still show warming. Warming at a slower rate than recent decades, but still warming... from both sources. Ergo, any 'internal variability' which is going on is getting overwhelmed by an external forcing.
86146. e at 01:35 AM on 11 May 2011
       Tracking the energy from global warming
       Tom @ 129, If the function goes below zero then the area added is negative. The key to Berenyi's analysis then is the choice of his baseline to calibrate the TOA measurements and convert them into absolute values rather than anomalies. He explained it in @109, though the justification wasn't very rigorous.
86147. dana1981 at 01:31 AM on 11 May 2011
       Lindzen Illusion #5: Internal Variability
       Arkadiusz - variability is noise and trend is signal. You're arguing a strawman. Nobody disputes that internal variability accounts for much of the temperature variability. Indeed, I specifically discussed this in the article (see Figure 4).

       "Dana1981 - once again, your analysis is absolutely too poor in the reference"

       The feeling is mutual.
86148. Berényi Péter at 01:24 AM on 11 May 2011
       Tracking the energy from global warming
       #129 Tom Curtis at 23:42 PM on 10 May, 2011 if a curve has a positive slope (ie, it increases in value with increasing x), then for equal segments on the x axis, the definite integral must increase with increasing x. Conversely, with a negative slope the definite integral must decrease with increasing x. That's not so. The only thing that follows is if a curve has a positive slope, the definite integral is a convex function (for negative slope it is concave). Convex or concave functions can have either positive or negative slopes, or their slope may change sign (at most once).
86149. Byron Smith at 00:20 AM on 11 May 2011
       Upcoming 'Climate Change Denial' book launches in Sydney and Canberra
       That's awesome to get Carr and Hewson behind this project.
86150. KR at 23:58 PM on 10 May 2011
       Lindzen Illusion #5: Internal Variability
       Ken Lambert - I'm well aware of the data sources; ARGO started deployment around 2000, and XBT and other measurements preceded that. I'm always saddened by claims that "imperfect data" means "no data at all" - that's tantamount to claiming that without perfect knowledge we know nothing at all, which is a fallacy. XBT data has some serious calibration issues and requirements to extract meaningful data, and ongoing reanalysis of the data and collection methods have continually improved it. Nothing is perfect, but it's certainly not invalid data as you claim. It provides a great deal of data for determining a statistically relevant trend line. On the other hand, given the variation seen in even the ARGO data (+/-2*10^22 joules over 3 years or so) a 5-6 year average is not statistically significant. To wit: "the fallacy of incomplete evidence is the act of pointing to individual cases or data that seem to confirm a particular position, while ignoring a significant portion of related cases or data that may contradict that position" - classic cherry picking.

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