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Comments 62601 to 62650:

62601. keithpickering at 03:59 AM on 4 March 2012
       Wall Street Journal 'Skeptics' Misrepresent the IPCC
       Anteros @22 "It seems you would all rather take the word of a sketchy, hand-drawn impressionistic graph than the specific written predictions of the FAR." The graphs and the text agree, when extended out to 2100. But the WSJ didn't extend their graphs out to 2100. And it is clear, looking at the graphs, that the IPCC projections indicate that the early part of their projection (the part we're in now) shows warming at a lower rate than the overall century-long rate. It is therefore utterly decpetive for the WSJ to use the overall century rate as the IPCC projection for the first twenty years: that wasn't the IPCC projection at all, for those first twenty years. "We used the 0.3 degrees per decade from the prediction of the FAR BAU. As I pointed out in my first comment, the error was in the SkS post above, suggesting that the [estimated from a graph] 0.32C was closest to the high climate sensitivity. It isn't - it is the 2.5C/2xCo2 best estimate." It is for the first twenty years. If the WSJ had wanted to be honest, they could have published the actual IPCC graph, which actually goes out to 2100. They didn't, and because they didn't, they gave a false impression of "where we should be now". "The FAR predicted, specifically that the BAU scenario would eventuate if few or no steps were taken to limit emissions of GHG's. And for those people clutching at straws with the Montreal protocol, that was signed and sealed 3 years before the IPCC FAR." The Montreal Protocol did not enter into force until 1989, and it is clear from the details of the emissions scenarios that neither BaU nor Scenario B anticipated any significant reduction of CFCs. See FAR Annex, figure A-3.
       Response:

       [DB] Fixed spacing.

62602. dana1981 at 03:55 AM on 4 March 2012
       Wall Street Journal 'Skeptics' Misrepresent the IPCC
       Bob - yes, there are really a lot of problems with the WSJ graphic, and we've only touched on a few here. The link in comment #1 to our post on the subject shows how to do the analysis properly.
62603. Bob Loblaw at 03:35 AM on 4 March 2012
       Wall Street Journal 'Skeptics' Misrepresent the IPCC
       ...while I'm at it.... Hasn't anyone noticed (or did I miss a comment?) that the original "Reality vs. Alarm" graph has used the trick that Tamino talks about here? They've started each IPCC prediction from the single value for that year, rather than a more realistic middle-of-the-noise value. The peak temperature for 1990 gives the "IPCC 1990" line a jump start above all the rest. If that projection started at 0.1 instead of 0.3, then the line wouldn't be that far off. By using 0.3, the graph is assuming that whatever caused the temporary upward spike in 1990-1991 will never go away as the "IPCC 1990" projection moves forward in time.
62604. Bob Loblaw at 03:21 AM on 4 March 2012
       Wall Street Journal 'Skeptics' Misrepresent the IPCC
       Coming in late.... It looks like Anteros (or the sources he/she is using) are playing the following game: - both the expert and the fake skeptic agree that C = A * B - the expert says "my best estimate of B is 2.5, but it could be as low as 1.5 or 4.5" - the expert says "I don't know what A is going to be in the next 20 years. If it is 10, then C will probably be 25, but it could be as low as 15 or as high as 45, because of my uncertainty in B. Let's call that value of A 'Business as Usual'. If A is 5, then C will probably be 12.5, but in the range 7.5 to 22.5. If A is 2, then the range for C changes to 3 to 9, with a best estimate of 5". - 20 years later, it turns out that A was about 4, and that C was about 12, which implies that B is about 3. - To the expert, none of the scenarios for A were matched exactly, but the results for C = A * B, lead to only a slight change in the "best estimate" for B (within the range from 20 years ago), so the expert is pretty happy and thinks she's done well. After all, her area of expertise is in the estimation of B and the measurement of C, not guessing what will happen to A. - the fake skeptic, on the other hand, is claiming that the expert predicted that A would be 10 and B would be 4.5, so C should have been 45, so the fact that C was 12 means that the expert got everything wrong and can't be trusted to give us an accurate value for B. Whether the fake skeptic is really that silly, or thinks everyone else can be fooled is an exercise for the reader.
62605. Bob Loblaw at 02:51 AM on 4 March 2012
       Greenhouse Effect Basics: Warm Earth, Cold Atmosphere
       dunc461: Again,a review of some "first principles". Gases do only emit and absorb at certain wavelengths (aka wave numbers), and this is a basic principle of spectroscopy. In Planck's law, emissivity is a function of wavelength. More so, Kirchhoff's Law says that emissivity equals absorptivity at the same wavelength (all other factors being equal), so if CO₂ is absorbing at a particular wavelength, it should also emit at that wavelength. ...but as Tom has pointed out, energy absorbed by one molecule can be transferred to other molecules, so the bulk radiation emitted from a layer of the atmosphere has properties that are a mix of the bulk atmospheric constituents, not the single (or few) gases that do the absorbing. In your last post, I think you've roughly got the idea, but the way you are looking at it is a bit unusual, and you have missed one extremely important thing. The unusual part is that in radiative transfer, you usually just think of the upward-directed and downward-directed fluxes as individual values that occur (or can be measured) at a point in the atmosphere - not "generated by the layer below" - because it doesn't matter if is was emitted by the layer below, or whether it just passed through the layer below having been emitted from other layers further down. The usual way of describing this process is to use Beer's Law. Thus, the heating due to IR absorption is (upward IR)*(portion absorbed) + (downward IR)*(portion absorbed). This is just mathematical arrangement, however, and is done that way because it is easier to see what is going on and arrange things for computer calculation. The error is that you've forgotten about solar radiation. It is also being absorbed (according to Beer's Law), and needs to be included in the energy balance.
62606. Bob Loblaw at 02:22 AM on 4 March 2012
       Postma disproved the greenhouse effect
       Re YOGI@63 Hmmm. You seem to feel that cloud must be warmer than you (or the surface) to "feel the warmth". How about these conditions?: a) clear sky, warm night, surface at 30 degrees C, so upward-emitted IR is about 480 W/m^2. Back radiation from clear sky about 340 W/m^2, which translates to an apparent sky temperature (for the purposes of IR radiation) of about 5 C. Net IR at the surface is -140 W/m^2 (i.e. a loss of 140 W/m^2). Feels cool. [Although I've selected these temperatures arbitrarily, they are realistic.] b) Identical to a), except that cloud has moved in at an altitude of about a kilometer, and the base of cloud is at about 25 C (i.e. still colder than surface). Back radiation from sky is now from cloud, not clear sky, and is about 450 W/m^2 (based on 25 C). Net IR at the surface is now only -30 W/m^2 (loss of 30), so the loss of energy from the surface is reduced from 140 to 30 W/m^2 - or only about 21% of what it was. [Again, arbitrary, but realistic, numbers.] To me, the second case (substantially less net IR loss from surface) will "feel warmer", even though the cloud is cooler than the surface (or me). Do you disagree with this scenario? Are you trying to say that the surface (or you) will feel no extra warmth unless the overlying cloud is actually warmer than the surface?
62607. paulhtremblay at 01:58 AM on 4 March 2012
       Wall Street Journal 'Skeptics' Misrepresent the IPCC
       >>If the only thing the IPCC was offering up to the world was an estimation of climate sensitivity, the FAR would have been a very short document. That's a very disingenuous argument. It assumes that the IPCC's main goal consisted in predicting how much CO2 the world would release. In fact, that prediction consisted only a very small part of the IPCC report, and as others have pointed out, has nothing to do with the science of AGW, and does not diminish the egregious errors of the WSJ article.
62608. Eric (skeptic) at 01:31 AM on 4 March 2012
       Postma disproved the greenhouse effect
       YOGI, the presence of clouds at night will keep the earth's surface warmer (i.e. will inhibit radiational cooling), all other things being equal. The clouds can be any temperature from relatively warm low clouds to very cold high clouds but will mostly be cooler than the surface. Yet they cause the surface to be warmer than it otherwise would be.
62609. Tom Curtis at 01:25 AM on 4 March 2012
       Wall Street Journal 'Skeptics' Misrepresent the IPCC
       Anteros is clearly not interested in arguing his case in good faith. This is no surprise, for if he did argue it in good faith his case would vanish. Further, in order to prosecute his case, he is clearly prepared to misrepresent the IPCC, and anybody else that suites his purpose. Therefore I see no point in further discussion with him. I will note that when I took his criticisms at face value, and pointed out the consequences (@43 above), he merely dismissed it as "quibbles about hundredths of a degree". To show the significance of these "quibbles" below: The graph is the WSJ graph with the IPCC FAR 1990-2030 trend for scenario A shown in green. It also shows in yellow the IPCC FAR trend from 1990 to 2030 for scenario C, ie, the scenario that most closely matches the actual historical forcings if we allow for the IPCC FAR's incorrect estimate of forcing for a doubling of CO2; and in orange the trend for scenario D, as discussed above. Anteros can talk about quibbles as much as he likes, but it is transparent that had the WSJ 16 correctly represented the IPCC FAR projections (by any reasonable standard of "correctly") it would have significantly weakened their case. Anteros has suggested that we cannot learn from past mistakes if we do not recognize them. He is correct, which is why it is heartening that in both SkS discussions the nature of the errors made in IPCC FAR have been clearly identified. This contrasts sharply with Anteros and the WSJ 16 whose sole purpose seems to be to point vociferously at the error without discussing its causes, thereby distracting people from any real thought on the situation.
62610. Dikran Marsupial at 01:01 AM on 4 March 2012
       The Independence of Global Warming on Residence Time of CO2
       owl905 (i) The ice core data shows that even through an event as extreme as a major glaciation, the response of the natural carbon cycle is a change of only about 90-100 ppm, and in each case, an equilibrium is restored on the scale of tens of thousands of years. This is true, even though CO2 is thought to have provided positive feedback amplifyng the change in forcings. So why doesn't this positive feedback result in runaway warming or a snowball earth? Simple, there are other feedback mechanisms that exist, that oppose it. David Arher's primer on the carbon cycle is well worth reading, one of the things that it explains is why CO2 can provide positive feedback on short (by geological standards) timescales and negative feedback on longer timescales (via the "weathering thermostat") (ii) You wrote "arguing in favour a return to natural levels in a useful period of time" I am arguing no such thing. The adjustment time estimate of 74 years is likely an underestimate of the most rapid response of the oceans to an increase in CO2. This won't bring us back to pre-industrial levels. For that you need the slower response processes by which carbon is taken down into the deep ocean (thousands of years) and a full return to pre-industrial conditions is only possible by permanent sequestration of the carbon back into the lithosphere by weathering, which will take tens to hundreds of thousands of years. This is mentioned in my paper and links are given to more authoratative works. We can however stabilise CO2 levels much more quickly by cutting emissions to a point where they match environmental net uptake, which will limit the change to our climate. (iii) Additionally, your remark to MHauber that the missing CO2 accounting is virtual proof of a mystery sink is far beyond what the accounting, the chaotic nature of the pollution, or the science, supports." The sink isn't a great mystery, we know that the carbon is taken up by the other reservoirs, but we don't know exactly how much is going into each reservoir. However the point is that assuming conservation of mass, we don't need to know where in the natural environment the carbon is going to know with high confidence that it is being taken up by the natural environment. If you think this is beyond science, then the mass balance argument has appeared in several papers, at least one of which was referenced in my paper. I suspect the reason it doesn't appear more often is that it is so obvious as to be taken for granted. If you think it is false, then please do point out which step is incorrect. (iv) "And that ocean 'carbon sink' is so poor, ocean acidification has become one of the great pollution problems. That's exactly why suggestion of oceanic sequestering of a decade ago went to the trash heap. " Actually that is not correct. The surface waters are still taking up substantial amounts of anthropogenic emissions (note the evidence of an increase in the airborne fraction is highly equivocal, which suggests that the surface ocean has not yet saturated). The thing that limits the rate at which the oceans can take up CO2 on longer timescales is the transfer of CO2 from the surface waters to the deep ocean. On long timescales, the oceans are still very powerful carbon sinks.
62611. dunc461 at 00:36 AM on 4 March 2012
       Greenhouse Effect Basics: Warm Earth, Cold Atmosphere
       Tom Curtis @51 Thanks, I really appreciate your help and look forward to your future posts. It really didn’t make sense to me that the energy absorbed would only be emitted at certain wavelengths. That is why I was looking for higher "window" rates at the top of the atmosphere. Lapse rate is a new term for me. My current understanding is that lapse rate is defined as “The rate at which air temperature falls with increasing altitude.” and it is effect of the GHCs on lapse rate that causes the ”greenhouse” effect. In simple terms, am I correct in saying that the temperature of given layer in the atmosphere (except the top and bottom layers) is the temperature at which the sum of the following is equal to zero. BBR = Black Body Radiation 50% BBR Generated in the layer below + BBR that passed through the layer below + 50% BBR Generated in the layer above + BBR that passed through the layer above + Heat of absorption by GHC +/- Sensible Heat gain or loss by convection */- Latent Heat gain or loss - Heat of adiabatic expansion - Portion of pass through BBR from layer above to layer below - Portion of pass through BBR from layer below to layer above - 50% BBR Generated to the layer below - 50% BBR Generated to the layer above = 0
62612. Bob Lacatena at 00:32 AM on 4 March 2012
       Wall Street Journal 'Skeptics' Misrepresent the IPCC
       52, Anteros, The problem is that any focus on the "prediction" and the "error" concerning the emissions scenario is a huge waste of time, a distraction, and down-right silly. If the emissions scenario was inaccurate for a period of five or ten years it simply means they failed to properly predict the economics and policies of an entire world of hundreds of nations and billions of people over a very short time frame. What is more important is that it says nothing whatsoever about the science. And it provides no comfort whatsoever to those who wish to claim that the science is invalid. You are like a man who has been told he as diabetes because you eat too much ice cream, but the doctor was wrong about the ice cream, your real sin is chocolate cake. So do you walk out of the doctor's office whistling gleefully because he was wrong about the factors behind your diabetes? Your focus on the emissions scenario and your eagerness to use words like "big error" and "wrong" demonstrate nothing except for your own narrow focus and apparent wish to ignore the science at any cost. And your eagerness to declare the entire process as wrong rather as a result, rather than to recognize that the difference in emissions scenario confirms, rather than diminishes, the strength of the science, makes all of your words suspect.
62613. Dikran Marsupial at 00:29 AM on 4 March 2012
       Postma disproved the greenhouse effect
       YOGI you have been asked to clarify your position and give an explicit answer on two questions. Instead you have given only the vaguest response possible. This is an indication that you are trolling. Please demonstrate that you are not by giving direct, unambiguous answers to the questions you have been asked.
62614. Anteros at 00:22 AM on 4 March 2012
       Wall Street Journal 'Skeptics' Misrepresent the IPCC
       Lotharson - I'm not sure you understand actually what a prediction is If the only thing the IPCC was offering up to the world was an estimation of climate sensitivity, the FAR would have been a very short document. It baffles me that you don't understand the comment "the emissions scenario was the big error". Unless you want to backtrack and say it was the climate sensitivity? When you say "the BAU scenario never eventuated you are absolutely right. But you fail to see that it was defined in a specific manner - that did eventuate. In other words "few or no steps were taken to limit the emission of GHG's". So this is why Barry Bickmore said the predictions were "way off" and Gavin Schmidt said they were "wrong" - because they were What is so hard to understand/admit about that? Of the two constituents of the prediction, one of them was very wrong. See Gavin's original comment for clarification if you're still confused.
62615. Lotharsson at 23:30 PM on 3 March 2012
       Wall Street Journal 'Skeptics' Misrepresent the IPCC
       Anteros:

       The emissions scenario was the big error in 1990

       Don't be ridiculous - and don't fallaciously pretend that there was only one scenario. They provided four, precisely because they couldn't predict what the world would do. It's horrendously illogical and deeply disingenuous to complain that predictions predicated on a scenario that did not eventuate are wrong - especially when other scenarios were provided that were much closer to realised emissions. Speaking of which:

       For the BAU scenario ...

       How many times do people have to point out that the BAU scenario never eventuated, and therefore it is invalid to compare BAU scenario projections/predictions with observations before you understand that insisting on such an invalid comparison is utterly fallacious? Every single claim anyone makes about FAR temperature predictions that presume a BAU scenario is moot. Every single one. (Which doesn't leave many of yours in play.) For example, acknowledging that point entirely collapses your argument that the WSJ "FAR" trend line is somehow a valid and non-misleading choice because it is based on BAU/best sensitivity. If that's how they chose it, they are engaging in deliberate deception or deep incompetence. Clearly the only predictions/projections from FAR that can be validly compared directly to subsequent observations are those for scenarios that are reasonably close to the forcings that actually transpired - i.e. Scenario D, or for reasons explored above possibly Scenario C. And that in that case, even the high estimate in the table given in the OP was about 0.25 C per decade averaged over the century (and even less in initial decades), which is already well below the "FAR" trend line drawn by the WSJ. And the best estimate was somewhere between 0.17 and 0.18 C per decade - which is way below the WSJ trend line. The WSJ clearly did not choose the "best" estimate for anything approaching the actual forcings, which means they did indeed exaggerate the FAR projections. What part of this do you disagree with? And if you absolutely insist (although thus far without any supporting evidence) that the written text about predictions/projections is more authoritative than the graphs, then under the only valid scenarios for comparison with observations we have (from the IPCC quote given above):

       "...just above 0.1°C per decade (Scenario C) and about 0.1 °C per decade (Scenario D)"

       (noting that those estimates did not provide uncertainty ranges in the quoted text). That comparison makes the WSJ "FAR" trend line egregiously overstated (i.e. by a factor of more than 3x), wouldn't you agree?
62616. Riccardo at 23:26 PM on 3 March 2012
       Postma disproved the greenhouse effect
       Clouds warmer than the surface? It's called temperature inversion and does not lead to the formation of clouds.
62617. CBDunkerson at 23:16 PM on 3 March 2012
       Wall Street Journal 'Skeptics' Misrepresent the IPCC
       I'm sorry, but why are we indulging Anteros's increasingly convoluted semantic 'justifications'? Sirrah. You entered this thread with a false quotation; "Based on current model results, We predict: An average rate of increase of global mean temperature during the next century of 0.3C per decade (with an uncertainty range of 0.2-0.5C per decade)" So far as I can see you have never acknowledged or explained this. So long as that remains the case I see no reason to believe that you are willing or able to discuss matters in good faith. You also seem unable to acknowledge that the BAU emissions scenario did not come to pass. As you say, it assumed that no steps would be taken to mitigate GHG emissions. Instead, we have seen the successful implementation of the Montreal Protocol (hardly a given when the research papers upon which FAR was based were written), the spotty implementation of the Kyoto Protocol, numerous smaller efforts at GHG reduction, and the collapse of the Soviet Union... all resulting in emissions measurably lower than those specified for the BAU scenario. Yet you continue to insist that this BAU scenario, rather than observed emissions, is the 'right' scenario to use for comparison to observed temperatures. Again, why should we take anything you say seriously when you are insisting that we should ignore observed reality? If we take the 2.5C 'most likely' sensitivity range from IPCC FAR, actual observed emissions, and the fact that the IPCC stated warming is expected to be lower in early decades and higher in later (rather than the straight line the WSJ 16 used) then we find the results are consistent with observed warming. The only way you get the IPCC FAR being 'way off' is by insisting on using the BAU Scenario A emissions... which are 'way off' from what actually happened. Thus, your sole objection would appear to be that the IPCC presented an emissions scenario which did not come to pass. In fact, they presented several. Because there was no way they could possibly know what mitigation efforts and economic conditions would exist in the future. Your insistence on focusing only on the highest of those possible scenarios as 'their prediction' is thus perverse.
62618. YOGI at 23:12 PM on 3 March 2012
       Postma disproved the greenhouse effect
       Back-rad works for sure, you can feel the warmth of clouds on a cold night. So as long as it warmer than the surface, I have no objection.
62619. Anteros at 22:15 PM on 3 March 2012
       Wall Street Journal 'Skeptics' Misrepresent the IPCC
       HH @ 47 To confirm that we're not disagreeing about obvious things. The CS of 2.5 is certainly close to the current best estimate. The predictions indeed have two fundamentally different components - the emissions scenario and the CS. Either (or both) can be the reason a prediction fails to match subsequent events. The emissions scenario was the big error in 1990.
62620. Anteros at 22:10 PM on 3 March 2012
       Wall Street Journal 'Skeptics' Misrepresent the IPCC
       Tom Curtis - I'm a bit baffled. You state that the word prediction is in the title of the SkS article. Indeed - that would lead one to believe there was going to be some reference to the IPCC FAR prediction. There isn't - at all. It is indeed true that the word is allowed in reference to a 1975 paper. This seems to me to prove my point - and I apologise for not anticipating some astonishing pedantry. It is true, then, that the word 'prediction' occurs once in the article, having nothing whatsoever to do with the IPCC FAR. Do you have any concern about why the predictions of the FAR vanished completely in an article about the FAR predictions. If the WSJ authors had done that, what might you have (legitimately) said? You claim that the FAR prediction comes with an error range. Again, indeed it does, but the limits of that error range (the specified uncertainty) are merely the two other CS's considered - 1.5 & 4.5C/2xCo2. For the BAU scenario and the best estimate of 2.5C/2xCo2 there is only one prediction - 0.3C per decade. Whatever quibbles there are about hundredths of a degree, the claim that the WSJ line is nearest the 'high' sensitivity is false. It is nearest the best estimate. I should repeat, again, that from the very beginning of this thread (and the thread at RC which prompted this one) I have made the point that I agree with Professor Bickmore's view which drastically disagrees with the original SkS article. That was - and is - the motive for my commentry. Hyperactive Hydrologist - the predictions of the FAR given to the relevant world leaders by the IPCC were specified in both the SPM and the Overview of the FAR. Tom Curtis quotes them @ 13. As I have mentioned previously the 1992 UNFCCC was constructed and signed on the basis of the FAR predictions. The fact that, as Barry Bickmore says, they were "way off" is not something to sweep under the carpet or to pretend never happened. Before moving forward with better predictions (as happened by SAR '95) it is surely important to admit that the predictions were, in fact, "way off". To hide from that fact is disingenuous.
       Response:

       [DB] To be clear, the individual perpetuating "astonishing pedantry" is you.  You entered this thread with a straw-man mis-quote and have been tearing at that house of cards you erected since.

       To hide from that fact is indeed disingenuous.

62621. Hyperactive Hydrologist at 21:59 PM on 3 March 2012
       Wall Street Journal 'Skeptics' Misrepresent the IPCC
       Apologies, It seems I failed in reading the executive summary. The word predicted appears in point e) in relation to the BAU scenario. However the BAU scenario assumes a certain emission trajectory and radiative forcing and therefore can be seen as a prediction. I feel like I am quibbling over semantics. For me the important point I am taking from this article is that a large proportion of the uncertainty in climate models lies with the assumptions made in the scenarios. This for me increase my confidence in the actual models.
62622. Hyperactive Hydrologist at 21:18 PM on 3 March 2012
       Wall Street Journal 'Skeptics' Misrepresent the IPCC
       Maybe we need to include some definitions taken from the TAR. Unfortunately they didn't seem to do a glossary for the FAR. Climate prediction A climate prediction or climate forecast is the result of an attempt to produce a most likely description or estimate of the actual evolution of the climate in the future, e.g. at seasonal, interannual or long-term time scales. See also: Climate projection and Climate (change) scenario. Climate projection A projection of the response of the climate system to emission or concentration scenarios of greenhouse gases and aerosols, or radiative forcing scenarios, often based upon simulations by climate models. Climate projections are distinguished from climate predictions in order to emphasise that climate projections depend upon the emission/concentration/ radiative forcing scenario used, which are based on assumptions, concerning, e.g., future socio-economic and technological developments, that may or may not be realised, and are therefore subject to substantial uncertainty.
62623. Hyperactive Hydrologist at 21:11 PM on 3 March 2012
       Wall Street Journal 'Skeptics' Misrepresent the IPCC
       Anteros, I am really confused by your "predictions" "projections" issue. I have looked through the IPCC FAR chapter 6, the modelling chapter, and the title of sub chapter 6.6, containing the modelling results, clearly states - 6.6 Projections of Future Global Climate Change. The chapter itself contains the word predictions twice. Both occasions in the introduction when discussing types of climate models. The word prediction never occurs in the sub chapter 6.6.
62624. Tom Curtis at 21:08 PM on 3 March 2012
       Wall Street Journal 'Skeptics' Misrepresent the IPCC
       Anteros @22, I am happy to concede that you used whatever method you claimed, but unless you are one of the authors of the WSJ article, or have received private communication from them, your conjecture about the method they used has no more standing than does Keith Pickering's conjecture. Never-the-less, let us assume that you are right. So, suppose we examine the IPCC FAR to see what their prediction of temperature rise was for the first few decades of the 21st century. From the executive summary of Chapter 6, we read:

       "e) Based on the IPCC Business as Usual scenarios, the energy-balance upwelling diffusion model with best judgement parameters yields estimates of global warming from pre-industrial times (taken to be 1765) to the year 2030 between 1.3°C and 2.8"C, with a best estimate of 2.0°C. This corresponds to a predicted rise trom 1990 of 0.7-1.5°C with a best estimate of 1.1^oC. Temperature rise from pre-industrial times to the year 2070 is estimated to be between 2.2°C and 4.8°C with a best estimate of 3.3°C This corresponds to a predicted rise from 1990 of 1.6°C to 3.5°C, with a best estimate of 2.4°C"

       You will notice that: 1) The best estimate temperature rise from 1990 to 2030 is 1.1 degrees C, or 0.275 degrees C per decade. That is 11.3% less than the trend shown by the WSJ article (estimated as 0.31 C per decade by pixel count on the graph), so on your terms they have over estimated the IPCC FAR prediction by 12.7%. That is the very best that can be said for your,and the WSJ 16's case, and it isn't much. 2) The best estimate temperature rise from 1990 to 2070 is 2.4 degrees C, or 0.3 degrees C per decade. That is 9% greater than the projected trend per decade from 1990 to 2030. Therefore your frequently made contention that the IPCC FAR "predicted" a constant rate of temperature increase over the full century is false. Therefore you are not justified in using the stated average trend over the full 110 year period from 1990 to 2100. 3) The prediction comes with an error range, the low end of which is a 0.7 degree C rise from 1990 to 2030. That corresponds to a decadal trend of 0.175 degrees C per decade. This compares to the 0.185 degrees C per decade from the instrumental record (GISTEMP) over the period 1990-2011 (0.16 HadCRUT3, trends from woodfortrees.org). The IPCC FAR clearly indicated that short term variability would prevent a monotonic increase, saying:

       "Because of other factors which influence climate, we would not expect the rise to be a steady one."

       Therefore to show that their "predictions" had failed, you would need to show that temperature increases had fallen outside error range on all temperature series. Clearly, neither you nor the WSJ 16 have done so. What is more, purporting that "... the projections exaggerate, substantially, the response of the earth's temperature to CO2 ..." while not showing the error bars on the prediction, when those error bars show the prediction has not yet been falsified is deceptive conduct. So much can be said using your, and (as you claim) the WSJ 16's standard. That is, even if their approach was correct, they have significantly overstated the predicted trend, failed to acknowledge that the trend increases over time during the century, and failed to show error bars which would refute their primary claim in relation to the graph. But their standard is not correct. It amounts to interpreting a conditional as a direct statement. In every location that the IPCC FAR makes a temperature "prediction", they actually make three or four, specifying a prediction under BAU, and then specifying the prediction for other forcing scenarios. Therefore they do not predict that temperatures will rise by 1.1 degree C by 2030. Rather,they predict the temperature increase on the assumption of one forcing scenario, and then specify it for other forcing scenarios. Therefore it is not true to say they predicted a given temperature increase without specifying the forcing scenario used. There predictions have the logical form of: If forcing scenario A, temperature range A. As is shown above, the actual forcing scenario followed was scenario D, and therefore the IPCC FAR prediction for events as they turned out is their prediction for scenario D. A case can be argued that we should adjust the IPCC FAR predictions to account for their overestimate of the forcing of a doubling of CO2, which they overestimate by 110%. In that way you would make their "predictions" conditional on changes in GHG concentrations rather than on changes in forcings. Based on that, an actual forcing of +0.63 W/m^2 should be treated as a forcing of 0.7 W/m^2 in assessing their predictions. On that basis we should use their scenario C predictions (0.18 C/ decade) rather than their scenario D predictions. But there is no basis for using their scenario A predictions, because the projected changes in GHG concentrations did not come to pass. This insistence that conditionals be treated as direct statements is bizarre. Done consistently, it literally allows you to infer anything you want, and hence is the sign of a fool. Done strategically it is the sign of a scoundrel who has no compunction in ignoring rational reasoning for rhetorical purposes. It is of a piece with your still unacknowledged, and still unapologetic misquotation of the IPCC FAR.
62625. Tom Curtis at 19:38 PM on 3 March 2012
       Wall Street Journal 'Skeptics' Misrepresent the IPCC
       Anteros @36, the original SkS post on the FAR contains the word "predictions" twice - once in the title and again when referring to "Broecker's 1975 prediction". Your original claim was,

       "Now, my point was that you never mentioned [any] of this in your article. You never mentioned the word "prediction" once."

       Clearly that claim is false. Grow a set and admit error.
       Moderator Response: [Riccardo] unclosed tags fixed
62626. Albatross at 19:15 PM on 3 March 2012
       Wall Street Journal 'Skeptics' Misrepresent the IPCC
       Anteros, "You misrepresent me by saying I claimed Keith never used the word 'prediction'. I referred to the original post, as you did, and which was discussed at RC - which you have referred to yourself." I find it ironic you taking exxception to people (accidentally) misprepresenting you when you misrepresented Gavin Schmidt. However, that I misrepresented you was unintentional (it really was), and I apologise for that. Here we tend to speak to the thread at hand, so I naturally assumed that you were discussing Keith's post. Unfortunately, you seem determined to be hung up on semantics-- one needs to step back and look at the bigger picture and the topic of this thread-- Lindzen using a chart that does not support his claim that the models exaggerate the warming (i.e., climate sensitivity). Surely we can all agree on that point. Do you agree that their claim that the instrumental record supports a lower climate sensitivity is not supported by the literature, as I showed in my post 27 above. It is late here and I need to sign off. Alex makes some good points,and I hope that he can access the actual data instead of estimating trends off charts. Maybe we`ll get to the bottom of this yet. I look forward to seeing your list of errors made by Lindzen et al., whenever you get around to it of course.
62627. Albatross at 19:01 PM on 3 March 2012
       Wall Street Journal 'Skeptics' Misrepresent the IPCC
       Anteros @31, "You say I "claim to be a true skeptic". This is totally false - I have never made such a claim, and it seems you have made many other incorrect assumptions too." I'm really not sure how to interpret this, I was giving you the benefit of the doubt when I stated that you claim to be a true skeptic-- that is the deafult position, at least for a good scientist. But by your own admission you now state that you are not a true skeptic. That is a rather odd assertion for you to make. How Lindzen et al. arrived at that slope is actually not immediately obvious, because they failed to provide specifics. But this is actually all moot-- because what you keep failing to recognize is that the entire premise for their claim that the models are wrong relied on that figure, when the figure in fact does not support their claim. BAU did not happen as expected, as was explained to readers in the above OP, but Lindzen et al. did not share that with their audience. Now I am open to the possibility that Keith erred in his calculations in Table 1. Right now, however, it appears the only way of obtaining a slope of 0.3 C or more for 1990-2010 is to use BAU and a CS of 4.5 C.
62628. Alex C at 18:52 PM on 3 March 2012
       Wall Street Journal 'Skeptics' Misrepresent the IPCC
       I too am interested in how the 0.24 figure was obtained. I myself just did rough pixel-counting to get 0.5˚C over the time period in question (1990-2010), though that's not nearly as substantive as having the decadal means. I unfortunately cannot download the data, it's available here: http://cera-www.dkrz.de/WDCC/ui/Compact.jsp?acronym=IPCC-DDC_FAR_GISS_SCA but one needs to have a login to obtain it. Unless someone else knows of where this is available on the web...?
62629. Alex C at 18:50 PM on 3 March 2012
       Wall Street Journal 'Skeptics' Misrepresent the IPCC
       Anteros @37: I'm not of the opinion that the original WSJ article was referring to the high-end scenario. I think that your explanation of how the trend was obtained is understandable to reject that notion; however, I think that the means by which the 0.32 figure was obtained is incorrect. I also do agree that the AR1 prediction was wrong. It was based off of an incorrect projection of emissions (which is rather independent of the model, but anyways...), and used a slightly overestimating relationship between CO2 concentration and forcing (and maybe with other gases? I haven't looked into that). I think that the more recent models are much more reliable, being more sophisticated in both variable inclusion and also in resolution.
62630. Anteros at 18:36 PM on 3 March 2012
       Wall Street Journal 'Skeptics' Misrepresent the IPCC
       Alex C - So is the slope in the WSJ article closer to the 0.5C of the 'high' sensitivity? To your apparently substantive point - of course, the BAU predictions were wrong. That is the main reason the FAR prediction was wrong. My point is that it is important to admit it was wrong, before learning the relevant lessons.
62631. Anteros at 18:32 PM on 3 March 2012
       Wall Street Journal 'Skeptics' Misrepresent the IPCC
       Albatross - You misrepresent me by saying I claimed Keith never used the word 'prediction'. I referred to the original post, as you did, and which was discussed at RC - which you have referred to yourself. Keith's post wasn't even written then. As I said, I found no references to the FAR predictions - the word appeared not to exist. If you're giving people free passes this is what you're letting through. I'm sorry you feel the need to descend to a list of accusations. And it's a pity you insist on making false assumptions about what I am or what I believe.
62632. johngray at 18:31 PM on 3 March 2012
       Nordhaus Sets the Record Straight - Climate Mitigation Saves Money
       Hi Fairoakien - go to top of page see "MOST USED Climate Myths" point 3 "It's not bad"
62633. Alex C at 18:28 PM on 3 March 2012
       Wall Street Journal 'Skeptics' Misrepresent the IPCC
       Pardon the all caps NOT at my previous post mods, if you could either cross it out or fix it that would be appreciated. I had started to write several of those in, but caught myself - obviously not fully though.
62634. Alex C at 18:27 PM on 3 March 2012
       Wall Street Journal 'Skeptics' Misrepresent the IPCC
       Anteros @31: >>>The reason this is obviously incorrect is that the slope most closely matches the BAU prediction of 0.3C per decade. No it doesn't. You have not sufficiently addressed what I stated at 12, and Tom at 13, that the 0.3/decade trend is the average over the whole period, and is not the rate at the beginning of the time period - your point about 1˚C by 2025 brings the rate down to 0.286˚C/decade, NOT your 0.32˚C/decade, and what more you're still committing the same fallacy by averaging over a time period longer than the one you're trying to observe (i.e., the trend is less than 0.28 for the first two decades). Even more importantly, you have yet to respond to the points that AR1 BAU did not happen, and that their forcing relationship was overstated in AR1.
62635. Anteros at 18:21 PM on 3 March 2012
       Wall Street Journal 'Skeptics' Misrepresent the IPCC
       Keith Pickering - Can I enquire how you got your figure of 0.35C per decade for the 'high' sensitivity and the BAU scenario? I ask because the FAR states that it is 0.5C per decade. This is obviously behind the disagreement about which sensitivity the WSJ authors used to derive their graph.
62636. Albatross at 18:18 PM on 3 March 2012
       Wall Street Journal 'Skeptics' Misrepresent the IPCC
       Anteros 29, For the record I do not happen to agree with Dr. Bickmore's characterization of the FAR prediction. You clàim "You also make the false assumption that my purpose is to defend Lindzen et al - you are very much mistaken" That is not an assumption at all, it is based on your obsession with semantics while completely ignoring the multitude of errors, distortions and half truths made in the WSJ by Lindzen et al. I have yet to you on this thread take issue with the egregious errors made by Lindzen. How about you demonstrate for us that you are a true skeptic. Please list for us all here a list of the errors, distortions and problems in the two WSJ articles written by Lindzen et al. There are many to choose from so it should be fairly easy for you to spot them. Go for it. This thread is about Keith's OP and Lindzen et al's failed attmept to claim that the models exaggerate climate sensitivity-- again the entire premise of their argument is false. Also, you originally claimed that Keith never used the word "prediction" in the above OP, when you were shown that was wrong instead of conceding error you go ahead to make another false claim, "I found one example of the word prediction in the OP, and it didn't refer to the FAR predictions!!". Actually, it appears five times above, three times in relation to FAR. So far you have misrepresented Gavin Schmidt's position on this issue, accused Keith of erasing/removing text from FAR, and have demonstrated that you are not amendable to reason. You are kidding yourself at this point if you still believe that you have any credibility or that you are behaving as a true skeptic would.
62637. Chris Colose at 17:47 PM on 3 March 2012
       Greenhouse Effect Basics: Warm Earth, Cold Atmosphere
       Anthony, In general, the greenhouse effect depends intimately on the vertical temperature profile. Models of snowball Earth have a rather isothermal atmosphere (especially in winter) much like modern Antarctica, and this makes it difficult to generate a strong greenhouse effect. Tom is right about Titan, which has an organic haze upper layer (though the greenhouse effect wins out on Titan, this anti-greenhouse only partially cancels) and the problem is similar to the nuclear winter issue as well. As far as the CO2 "blip" in the center: as Tom notes, the stratopshere cools which somewhat offsets this effect (not seen in MODTRAN) and the decrease in emission toward the wings more than offsets the increase in the center. This is all accounted for in line by line radiative transfer studies.
62638. Albatross at 17:36 PM on 3 March 2012
       Wall Street Journal 'Skeptics' Misrepresent the IPCC
       Anteros, "You make the same mistake as Keith Pickering by saying the authors of the WSJ article use the "very high end of the climate sensitivity range" They don't - as I pointed out." Are you one of the signatories? Where in the WSJ article did they spell it out how they arrived at that slope? If it makes you feel any better, I find your condescending tone and recalcitrant attitude both here and at RC equally insulting. Regardless, the entire premise of Lindzen et al's graphic is false as I showed at 27 above. Any reasonable person will be able to recognize that. You continue to undermine your credibility and claim of being a true skeptic when you continue to give the disinformers who signed the WSJ article a free pass, and also when you attempt to distract everyone from their multitude of errors and distortions and misrepresentations. Do whatever your belief system compels you to do, but it will not and cannot change the facts or the physics. The climate system will continue to accumulate energy (at varying rates) in response to the positive planetary imbalance initiated by humans increasing GHGs and triggering positive feedbacks. Good night.
62639. Anteros at 17:33 PM on 3 March 2012
       Wall Street Journal 'Skeptics' Misrepresent the IPCC
       Albatross I'm sorry to see that you're not interested in discussing this issue - apart from ad hom sneers, you have steadfastly refused to engage with my criticism. Why would that be? You also make the false assumption that my purpose is to defend Lindzen et al - you are very much mistaken. If you read my comments, you will see that I was agreeing with Professor Bickmore that the FAR predictions were "way off" and in doing so, made a comparison the the rather different (and unjustified) claims by SkS. I found one example of the word prediction in the OP, and it didn't refer to the FAR predictions!! Perhaps you're counting the title and the SkS logo? Still, you haven't made an attempt to justify changing the language of the FAR and its central prediction - which has been expunged from the above post.
62640. Albatross at 17:15 PM on 3 March 2012
       Wall Street Journal 'Skeptics' Misrepresent the IPCC
       Adelady @25, No you are not missing anything.
62641. Albatross at 17:12 PM on 3 March 2012
       Wall Street Journal 'Skeptics' Misrepresent the IPCC
       The indignant claim is made @10 that: "The upper and lower uncertainty limits were, of course, model results from runs with 1.5 and 4.5 degC/2xCo2. Now, my point was that you never mentioned ANY of this in your article. You never mentioned the word "prediction" once." Someone clearly failed to read the OP. The emission scenarios and sensitivities (and various cominations) are listed in Table 1. The word "prediction" or "predictions" appears five times in the post. The fake skeptic also claims @10 that: "On the Realclimate thread Professor Barry Bickmore called the predictions "way off" and Gavin said they were "wrong"." This is what Gavin Schmidt actually said: "[Response: Note that projections are a function of two things - the scenario and the model. What was wrong in FAR was the scenario (too fast growth rate of GHGs, no aerosols, no ozone, no BC etc.), not the model (though the projections were with simple emulators not GCMs). Indeed, models today have similar sensitivities and with the same scenario will give the same temperature rise. - gavin]" So the claim in the WSJ made by Lindzen et al. that their graph demonstrates "that the projections exaggerate, substantially, the response of the earth's temperature to CO2" is pure and utter nonsense, and Gavin Schmidt does not buy it either. Someone here is being disingenuous and it is not SkS. Also, Lindzen et al. claim that "when one examines the historical temperature record throughout the 20th century and into the 21st, the data strongly suggest a much lower CO2 effect than almost all models calculate" is demonstrably false. See, for example, Hegerl et al. (2006). More recently Huber and Knutti (2011) who found looking by the conservation of energy over the instrumental record that: "The resulting distribution of climate sensitivity (1.7-6.5 C, 5-95%, mean 3.6 C) is also consistent with independent evidence derived from palaeoclimate archives." Lindzen et al. are wrong, so it is perhaps understandable why the fake skeptics continue to try and distract everyone from that inconvenient fact.
62642. Anteros at 16:55 PM on 3 March 2012
       Wall Street Journal 'Skeptics' Misrepresent the IPCC
       Albatross @ 23 You make the same mistake as Keith Pickering by saying the authors of the WSJ article use the "very high end of the climate sensitivity range" They don't - as I pointed out. I'm sorry that I couldn't see anything else through your rather insulting rhetoric. Keith Pickering - I'm surprised you used a 'corrected' graph to try to work out the predicted temperature rises from the FAR. They are spelled out in words (and the graphs constructed subsequently). The FAR is very clear in its predictions. As I noted, it means the WSJ line is closest to the 'best' estimate, not the highest. It's worth pointing out the caveat noted by the IPCC [because for some reason or other, nobody here has seen fit to mention it..] which is that WG3 estimates of what the BAU emissions would be were 20% higher than the estimates used for the model predictions. The message being, of course, that the IPCC FAR predictions could actually be quite conservative.
62643. adelady at 16:41 PM on 3 March 2012
       Wall Street Journal 'Skeptics' Misrepresent the IPCC
       Thanks keith, tom, dana, wingding, Uncle Tom Cobbley and all. I am constantly amazed at people unable to take advantage of a menu. The FAR offers a range of 12 choices without knowing which of them will turn out to be applicable. . 20 years later, it's perfectly obvious which of the original 12 are and are not still on the table. To make comparisons, we look for the best match with the inputs, then compare with the data for outcomes. What's so hard about that? Or am I missing something.
62644. Albatross at 16:27 PM on 3 March 2012
       Wall Street Journal 'Skeptics' Misrepresent the IPCC
       Err @22, " We used the 0.3 degrees per decade from the prediction of the FAR BAU" Is that the royal "we" or is the fake skeptic on this thread claiming to be a co-author of the diatribe written by Lindzen et al.? Otherwise, the onus is on Lindzen at al. to demonstrate and justify exactly how they arrived at that trend-- not their self-designated apologists. And said fake skeptic also has a rather inflated sense of entitlement as to which grievances of theirs must be addressed.
62645. Albatross at 16:12 PM on 3 March 2012
       Wall Street Journal 'Skeptics' Misrepresent the IPCC
       Well done Keith! This is yet another shameless example of Dick Lindzen and his fellow fake skeptics willfully (they do know better, or they can claim ignorance if they choose)distorting and cherry picking in order to confuse and mislead the public. They could only create their illusion by choosing the very high end of the climate sensitivity range and the most pessimistic emssion scenario. Worse yet, now in 2012 they try and claim that the prediction was wrong when they obvioulsy used the most pessimistic scenario possible. It is bemusing and uncompelling when certain vocal fake skeptics demosntrate their one-sided skepticism by nit picking and arguing strawmen, whilst giving Lindzen et al. free pass on their egregious errors. Lastly, it never ceases to amaze me how fake skeptics somehow manage to get stuck in the past (McIntyre is still obsessing about a seminal paper published in 1998), Lindzen and his fellow fake skeptics are infatuated with the first IPCC assessment report from 1990 (that was 22 years ago folks!), and Michaels is obsessed with a Hansen et al. paper written back in 1988. So much for their claims about advancing the science ;)
62646. Anteros at 15:54 PM on 3 March 2012
       Wall Street Journal 'Skeptics' Misrepresent the IPCC
       I don't know quite what to make of the fact that no-one has addressed my criticisms. It seems you would all rather take the word of a sketchy, hand-drawn impressionistic graph than the specific written predictions of the FAR. And if anyone is playing at semantics, it is those people [like the original article] that substitute the word 'projection' for 'prediction'. Tom Curtis @ 13 You say there is no justification for using the high sensitivity of graph A. Indeed - neither the WSJ article, or myself, did that. We used the 0.3 degrees per decade from the prediction of the FAR BAU. As I pointed out in my first comment, the error was in the SkS post above, suggesting that the [estimated from a graph] 0.32C was closest to the high climate sensitivity. It isn't - it is the 2.5C/2xCo2 best estimate. The idea that 0.3C per decade was implied to only average out later in the century is firmly rebutted by the prediction that temperatures would rise one degree by 2025 (if steps were not taken etc etc) To cut to the chase, this whole defence of a very poor prediction is that climate sensitivity is believed to be roughly what it was believed to be 20 years ago - and that this is the only way to judge whether the IPCC FAR prediction was accurate. Professor Bickmore, Gavin Schmidt and many others (including myself, obviously) disagree. The FAR predicted, specifically that the BAU scenario would eventuate if few or no steps were taken to limit emissions of GHG's. And for those people clutching at straws with the Montreal protocol, that was signed and sealed 3 years before the IPCC FAR. 194 countries signed the 1992 UNFCCC, on the basis of the predictions of the FAR. To even begin to learn lessons from the failed predictions, it is essential to accept and admit that the predictions were wrong. It isn't complicated, and the first step is to use the words used in the FAR, particularly the word 'prediction'.
62647. keithpickering at 15:36 PM on 3 March 2012
       Wall Street Journal 'Skeptics' Misrepresent the IPCC
       Well, I was going to say something intelligent, but it looks like everyone else said it already. Thanks Alex C, Tom Curtis, and Wingding.
62648. KR at 15:18 PM on 3 March 2012
       The Independence of Global Warming on Residence Time of CO2
       owl905 - The Earth climate is under a overall state of negative (damping) feedback, based upon the S-B relationship. The oscillations seen in paleo records are reflections of the climate stabilizing under various forcing conditions. Even the PETM resulted, eventually, in a stabilized climate, as the excess CH4 and CO2 were (over tens/hundreds of thousands of year) absorbed by weathering and the carbon pump to the ocean depths. The geologic balances are certainly not speedy, but they are there, and cannot be ignored. "...the record shows much longer interglacials before that time..." - Yes, driven by the Milankovitch cycles. Those provide the time frame for the glacial intervals. I don't believe Dikran (or anyone else, for that matter) is stating that CO2 levels, ocean acidification, or other climate change effects will "...return to natural levels in a useful period of time..." - but rather that they are stating that over the long term view the climate will find another equilibrium. Although perhaps one we don't find particularly pleasant... --- Whether we enjoy the process or not, the carbon cycle will stabilize over the long term - certainly after we've burned all the fossil fuels. But in the meantime, we're looking at a very long and unpleasant interval with global warming, mass extinctions, agricultural losses, and other issues that can be (hopefully) mitigated to some extent by acting while we're not over-committed to warming.
62649. KR at 15:08 PM on 3 March 2012
       Wall Street Journal 'Skeptics' Misrepresent the IPCC
       Anteros - I find it curious that you fail to recognize the conditional in the FAR. Namely, the statement: If this emission pattern, then this result You then criticize the rather old projections based upon emissions patterns that simply did not occur. In other words, you criticize the consequent while ignoring the influence of the antecedent. That's a failure of logic on your part. Until you acknowledge that, you are simply playing semantic games. You are certainly not invalidating the rather primitive FAR projections, which are still holding up well. At best, you are mistaken, at worst, you are misrepresenting the IPCC to insult it. I leave it up to your response to see which is the case here.
62650. Alex C at 15:00 PM on 3 March 2012
       Wall Street Journal 'Skeptics' Misrepresent the IPCC
       The point about the forcing/concentration equation being different might have some implications for how correct Figure 4 is, though not much. Comparing forcing figures is fine, since the relationship between forcing and temperature change has always been handled the same way, but if you want to compare true apples to apples, then concentration data between real world and the FAR models should be compared, not forcing. Comparing concentrations, and using the same forcing/concentration equation, the observed forcing should be slightly lower in Figure 4 above (or the model result slightly higher). By how much for either, I don't know.

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