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OPatrick at 18:52 PM on 11 May 2011Infographic: 97 out of 100 climate experts think humans are causing global warming
les, you're right that's the important point. The question leaves no ambiguity that the experts think human actions affect the climate and therefore the implication is that through our actions we can do something to reduce the problems we face. -
les at 18:38 PM on 11 May 2011Infographic: 97 out of 100 climate experts think humans are causing global warming
6 JoeRG /8 Heraclitus Interesting issue... maybe the important point is that we are in the causal loop in such a way that we can actually change things - continue to contribute to GW more strongly or stop the escalation. -
OPatrick at 18:28 PM on 11 May 2011Infographic: 97 out of 100 climate experts think humans are causing global warming
JoeRG, I'm sure everyone reading this has had the same thought, but I note that you missed out a significant word - the question included "significant contributing factor", which I would say nudges the brief headline "causing global warming" to an honest summation. We can't live our whole lives assuming the worst in human nature, no matter how strong the evidence seems to be. -
dorlomin at 18:19 PM on 11 May 2011Infographic: 97 out of 100 climate experts think humans are causing global warming
David Horton "Always puzzles me as to who the other 3% are!" Its hardly unusual for there to be a few contrarians in any field. Older scientists who have not moved with the paradigm shift and perhaps a couple of younger ones who were drawn to the field to challenge the “orthodox”. -
JoeRG at 17:56 PM on 11 May 2011Infographic: 97 out of 100 climate experts think humans are causing global warming
Dear John, Sorry for critisizing you, but with this post you gave a fine example of an incorrect conclusion. There is quite a difference between being a "cause" (your conclusion) and being a "contributing factor" (what was asked for). Nevertheless, it doesn't change the main evidence. -
villabolo at 17:31 PM on 11 May 2011Infographic: 97 out of 100 climate experts think humans are causing global warming
@1, David Horton: "Always puzzles me as to who the other 3% are!" No need to be puzzled. Based on the few whose ideology I've been able to ascertain that 3% are hardcore right wing ideologues and quite a few ultra-fundamentalists. Both are predisposed to be anti-whatever their ideology/religion happens to be. -
ScaredAmoeba at 17:15 PM on 11 May 2011Infographic: 97 out of 100 climate experts think humans are causing global warming
Doran 2009: "While respondents’ names are kept private, the authors noted that the survey included participants with well-documented dissenting opinions on global warming theory." Mmmm! the usual suspects. -
danno at 16:43 PM on 11 May 2011Infographic: 97 out of 100 climate experts think humans are causing global warming
the 1% is a handful of scientists funded by the fossil fuel industry? -
AndrewMF at 16:12 PM on 11 May 2011It's the sun
Thanks, that's helpful. :) AMF -
John Cook at 16:12 PM on 11 May 2011Upcoming 'Climate Change Denial' book launches in Sydney and Canberra
No plans for Adelaide or Melbourne, sorry. Haydn and my resources are limited and a tour of all capital cities is beyond us, I'm afraid :-( -
adelady at 16:03 PM on 11 May 2011Upcoming 'Climate Change Denial' book launches in Sydney and Canberra
Yes, Adelaide. I was wondering about that too. -
dana1981 at 15:16 PM on 11 May 2011Lindzen Illusion #6: Importance of Greenhouse Gases
"H20 vapor may not be always positive as a feedback. It depends where it is at."
Globally it's positive. -
Bern at 15:14 PM on 11 May 2011Infographic: 97 out of 100 climate experts think humans are causing global warming
Thanks for this, John - I'll be putting it to use quite shortly here at work! I particularly like the way you've distinguished between the "No it's not" and the "I'm not sure" categories. It reinforces the message, that those who think humans are not responsible are a very tiny minority. -
David Horton at 14:53 PM on 11 May 2011Infographic: 97 out of 100 climate experts think humans are causing global warming
Always puzzles me as to who the other 3% are! -
scaddenp at 14:30 PM on 11 May 2011Lindzen Illusion #6: Importance of Greenhouse Gases
Camburn, as far as I can see, your objection to Schmidt amount to "Models cant be right, so attribution cant be done, therefore CO2 isnt a problem". Or do you have better way to do it? -
dhogaza at 14:02 PM on 11 May 2011Lindzen Illusion #6: Importance of Greenhouse Gases
Go read the whole friggin' abstract, folks, to see how fragile the straw is that Camburn grasps at. The authors, in the abstract, say this, for instance: "it is important to establish what (if any) aspects of the observed trends survive detailed examination of the impact of past changes of radiosonde instrumentation and protocol within the various international networks." if any ... like, we don't really believe this ourselves, we're just putting the radiosonde data out there for people to look at and, hey, don't blame us, we're putting caveat after caveat in our abstract and paper. Camburn thinks it's significant, even though the authors think it probably isn't ("if any"). -
Marcus at 14:01 PM on 11 May 2011Upcoming 'Climate Change Denial' book launches in Sydney and Canberra
So when can we expect you in Adelaide Mr Cook? -
dhogaza at 13:59 PM on 11 May 2011Lindzen Illusion #6: Importance of Greenhouse Gases
"H20 vapor may not be always positive as a feedback. It depends where it is at." Or whether or not radiosonde data is of better quality than satellite data and model expectations, of which the authors of the paper you cite are clearly not convinced. Stick to pizza ... acquire enough empty boxes and you might begin to gain insight into how GISS Model E and other GCMs work. -
scaddenp at 13:58 PM on 11 May 2011It's the sun
Also, what the various temperature system do is determine a global temperature anomaly, (that is, a spatial average of anomalies because these are strongly correlated). It is extremely difficult to determine a global average absolute temperature that has any meaning. See Hansen 2008 for detail. However TSI is just a number. You can determine an anomaly if you like by subtracting from an arbitary baseline. It cannot change the shape of the curve however. -
scaddenp at 13:50 PM on 11 May 2011CO2 has a short residence time
"IPCC's Policymakers". What Policymakers are associated with the IPCC and what are they supposed to do? -
actually thoughtful at 13:37 PM on 11 May 2011What scientists are saying about Skeptical Science
I may be a Pollyanna here - or a realist. I can only speak for the US, but I think what will happen is we will have a year with many signs of AGW - basically the next El Nino, a 6-9 month string of "weather anomalies" that match what the science predicts. And that will essentially be a tipping point for a better policy in the US. We almost had that after the last El Nino (at that time even Republican candidates for office were in favor of cap and trade (which is ironically, a Republican idea that actually works)). Then the country convulsed over the economic problems (some of which, like the reliance of foreign oil, are integrally linked with AGW) and we lost the collective will. I don't think the loud, vocal 20% on the far right will ever get it. For them God will fix any major problems, and it is hubris to think humans have any role in climate (and this group is not swayed by science, they see conspiracy if anything challenges their core beliefs). There is already 20% on the other side that is ready to bury all cars and turn off all coal plants right away (although I think this group, of which I count myself, could be doing more NOW - how many of us have cut our emissions in half over the last 10 years, and plan on cutting them in half again in the next 10? We claim this is doable - so let us each lead the way!). So the 60% in the middle is either too busy, or is currently buying into the right wing propaganda as there isn't ENOUGH real world evidence that directly impacts their world. So, I think the next El Nino is the time to put forward a rational climate policy (I favor cap and dividend). In fact, given our ability to predict the timing and severity of an El Nino, it might make sense to time the debate of the policies such that the votes are taken at the summer-time peak of a strong El Nino. I am quite sure that a winter vote on climate change will not be as successful. Human nature trumps a strictly scientific analysis of the world (obviously climate change is still happening and a problem in January, but it is harder for the human mind to process it. Part of my work is as a heating contractor. My phone rings much more on September 1 (the first cold day in my part of the world) than on June 15 - when I have slack resources. Human nature).Response:[DB] Here's human nature:
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Publicola at 12:49 PM on 11 May 2011Meet The Denominator
Hi all, Poptech is on record claiming that articles on his list are "peer reviewed" because they "can be" peer reviewed: -------------------------------------- Poptech: "[My list] is overwhelming evidence of a peer-reviewed papers supporting skeptic arguments against AGW or AGW Alarm" Me: "Your joke of a list counts multiple 'viewpoint' - aka OpEd - articles authored by non-natural scientist Sonja Boehmer-Christiansen. How do you know that said articles have been peer reviewed?" Poptech: "Because these can be and you have not demonstrated otherwise." http://www.huffingtonpost.com/social/Poptech/climate-scientists-conference-2011_n_857588_87410332.html -
Camburn at 12:37 PM on 11 May 2011Lindzen Illusion #6: Importance of Greenhouse Gases
Pizza anyone? dana1981@42. You are totally correct. I was wrong in my ref to Dressler and h2o vapor. H20 vapor may not be always positive as a feedback. It depends where it is at. http://www.springerlink.com/content/m2054qq6126802g8/ -
Riduna at 12:29 PM on 11 May 2011Upcoming 'Climate Change Denial' book launches in Sydney and Canberra
Comments by Dr Hewson should be interesting. Particularly to Tony Abbott. -
DSL at 12:11 PM on 11 May 2011It'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. -
AndrewMF at 11:53 AM on 11 May 2011It'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. -
Eric (skeptic) at 11:22 AM on 11 May 2011CO2 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. -
Ken Lambert at 11:02 AM on 11 May 2011Lindzen 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. -
dhogaza at 10:42 AM on 11 May 2011Lindzen Illusion #6: Importance of Greenhouse Gases
Camburn ... dude ... it's a many pizza boxes model ... -
Tom Curtis at 10:20 AM on 11 May 2011Lindzen 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. -
RobertS at 09:54 AM on 11 May 2011Lindzen 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. -
dana1981 at 09:34 AM on 11 May 2011Lindzen 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. -
Camburn at 09:23 AM on 11 May 2011Lindzen 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. -
Camburn at 09:17 AM on 11 May 2011Lindzen 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. -
Tom Curtis at 09:11 AM on 11 May 2011Lindzen 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. -
Tom Curtis at 09:02 AM on 11 May 2011Lindzen 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. -
drrocket at 08:43 AM on 11 May 2011CO2 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. -
Bob Lacatena at 08:42 AM on 11 May 2011Lindzen 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. -
Albatross at 08:41 AM on 11 May 2011Lindzen 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. -
Camburn at 08:39 AM on 11 May 2011Lindzen Illusion #6: Importance of Greenhouse Gases
KR: I didn't want to argue over the deffinition of slab at all. -
scaddenp at 08:09 AM on 11 May 2011Lindzen 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). -
julienx2k2 at 07:46 AM on 11 May 2011Crux 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. -
KR at 07:32 AM on 11 May 2011Lindzen 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. -
Camburn at 07:19 AM on 11 May 2011Lindzen 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. -
scaddenp at 07:10 AM on 11 May 2011Lindzen Illusion #3 and Christy Crock #5: Opposing Climate Solutions
Ken, fair enough but you said, Victoria was 12.5% availability, not capacity. -
Bob Lacatena at 06:33 AM on 11 May 2011Lindzen 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. -
dana1981 at 06:24 AM on 11 May 2011Lindzen 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. -
RobertS at 06:16 AM on 11 May 2011Lindzen Illusion #6: Importance of Greenhouse Gases
Camburn @26, Your link doesn't support your definition. -
Camburn at 06:16 AM on 11 May 2011Lindzen 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. -
Camburn at 06:12 AM on 11 May 2011Lindzen 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.
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