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Comments 58151 to 58200:

58151. monkeyorchid at 18:18 PM on 1 June 2012
       In Search Of: Himalayan Ice Loss
       For clarity, I suggest adding "in rate" to the line: "with a sharp increase IN RATE after 1997 (Shahgedanova et al., 2010)"
58152. skywatcher at 15:52 PM on 1 June 2012
       Models are unreliable
       Clyde #537 - I see you have attempted to answer Bob and I's questions (both are similar). However, your answers consciously avoid any statement of why the expert in a field (heart surgery or climate) cannot become an expert modeller of a process in that field. Why is it that somebody, who has attained skill in understanding the processes of how something works, is precluded from encapsulating that knowledge in computer code? What I want to know is this: What is unique about a "modeller", that means neither a climatologist or a heart specialist can ever become one? How, in your opinion, do you become a "modeller"? Exactly what are the unique skills a modeller has? You see, fundamentally, what a "modeller" is, in this context, is someone who has the ability to generate computer code that results in an approximate representation of one or more processes in the climate system. They will have the ability to test that code, and to validate that code against expected results using synthetic data, as well as against real-world data. They can then correct their code or adjust the uncertainties accordingly. They will be able to estimate the uncertainties in their results and evaluate the strengths and weaknesses of their model. This is a technical skill, but one that is eminently achievable by physical/environmental scientists. By doing so, they become specialist climate modellers. You still have provided not one shred of justification as to why such scientists cannot do this. I don't actually believe you are willing to answer these questions adequately. Your subsequent casual comment concerning a Greenland climate paper equally shows you have little understanding of climatology, palaeoclimate, forcings, and regional versus global variations, to add to your evident failure to substantiate your original disparaging claims about climate modellers. Did you think warming/cooling was globally monotonic?
       Moderator Response: [DB] Fixed link.
58153. scaddenp at 15:09 PM on 1 June 2012
       Models are unreliable
       Clyde - that natural fires occur is not evidence against arson, but it would be better to direct comments to Climate has changed before. Computer models do "predict" past warming - its just that the forcing are different.
58154. Clyde at 15:05 PM on 1 June 2012
       Models are unreliable
       I hope this is not off topic for this thread. The reason i think its not is the paper gives more evidence of past warming be equal to or greater than today's. Making climate models in my view not reliable enough to pass new laws & regulations. You only get a small part & have to pay to read the full paper. No i didn't pay to read the full paper. Another paper with evidence of past warming being equal to if not more than today's. My apologies again for this mistyped hyperlink.
       Moderator Response: [DB] Your link is indeed off-topic for this thread. Future off-topic comments will receive moderation.
58155. Clyde at 14:55 PM on 1 June 2012
       Models are unreliable
       Bob Loblaw 534 First let me say i was only curious as to which was more complicated, GCM or HTML coding. I have no experience in GCM (big surprise i know -_^) coding. In the very little HTML coding I've been involved with its a pain in the butt. 1) What is your definition of a "computer modeler"? Somebody who can write the code & has the computer to run the code. 2) On what basis do you claim that any particular "climatology expert" is not knowledgeable about computer modeling, and how would this affect the work that they are doing? I'm going by say a doctor. A heart surgeon can operate on a heart, but that doesn't mean they can write the code & run it on a computer. If my comment left the impression i don't think any scientist has the ability to do both, that wasn't what i meant. 3)What else would I need in my background to convince you that I know enough about "computer modeling"? (My background was presented in this comment.) I don't recall saying you don't know enough about "computer modeling." I only "know" you from the brief interaction we've had here. The reason i asked you the question about the different coding was because you said you have written scientific code before.
58156. Peter42 at 14:53 PM on 1 June 2012
       IEA CO2 Emissions Update 2011 - the Good News and the Bad
       To scaddenp @14 (11.44 am 1 June 2012): Thanks for the information that wind/hydro/geothermal have no subsidies operating where you are. Would you let us know where that is, please? Tom Curtis’ suggestion (@ 16, 12.24 pm 1 June 2012) strikes me as an equitable approach, of carbon dioxide taxes in developed countries, while developing countries catch up. To Sphaerica @15 (12.12 pm on 1 June 2012): I try to separate motive from policy; a good motive behind a poor policy results in a poor policy, and a poor motive behind a good policy results in a good policy. My understanding of your post is that my statement about the need for inexpensive energy for developing nations, is false; your reason is that you distrust absolutely the motives of some or many or even all who present that view. Certainly the “cry of ‘we need cheap fossil fuel energy to help the poor’” may be hypocritical of some, but not all. Further, while I quite accept the genuine conviction of most who argue that we humans are responsible for most recent global warming, one must accept that not all who disagree are disingenuous. I continue to discuss this issue with quite a number of people: there are those who agree, disagree, or reserve their judgment. I’ve not found any to be disingenuous. Further in my #13 post there is an example from the Indus past, which illustrates the deleterious effects of major climate change on populations, in this case arising from non-human causes. My own view is that as well as other actions, we need to equip people better to be able to cope with climate change. Enabling them to lift themselves out of poverty is one such step.
58157. Clyde at 14:48 PM on 1 June 2012
       Models are unreliable
       Bob Loblaw 533 I read the comment you requested & understand your feelings about Pielke Sr. To the best of my knowledge his reason for turning of the comments on his blog was to avoid dealing with name calling/childish behavior. So far i haven't had that problem with you nor anybody else. This not the only time he has issued the challenge & not the exact page i was looking for. It does have the info needed if anybody wants to refute his claim. I would think if the models are as good as some say this should be an easy task. Read more here. This label, of course, can be avoided if the researchers provide quantitiative model and observational comparisons of multi-decadal regional and local predictions of changes in climate statistics, and show them to be skillful in terms of what metrics are needed by the impacts community. I invite anyone who has published such a study to present a guest post on this weblog alerting us to such a robust scientific study.
58158. skywatcher at 14:15 PM on 1 June 2012
       Models are unreliable
       Tom, that first graph you show is even more egregious for another reason - the projections are shown by Evans as being initialised from a single high point in the noise of the temperature record in 1988. In reality, Hansen's model runs begin before 1960, and the individual runs are already diverging by 1988, depending on the different settings [e.g. scenario A has no volcanic forcing after 1988] of the model: The scenarios A, B and C are spread over ~0.2C around 1988, and A does not cross B or C after this point (contrast Evans' A and B separation with Hansen's A and B). By doing this, Evans greatly exaggerates discrepancy between modelled and observed temperatures, a discrepancy not actually present (see in detail here at RealClimate, 3rd fig). Below is my estimate of the positions in 1988 of Hansen's Scenarios A, B and C (shaded grey circles), and Evans' start point for all three (blue square), based on GISS (used by Hansen) and UAH (used by Evans) data, with the temperature plots offset so they overlap in WoodForTrees plotting package: The reality is that much of the visual discrepancy in Evans' chart is a consequence of his misrepresenting the positions of the model runs w.r.t. to 1988 temperature. He thus shifts all three model runs much too high, compared to the temperature. Readers are left to ask the question why Evans chose to start all three model run plots from the same spot, a positions higher than any of the model runs as they were actually presented in Hansen's 1988 paper. They can then ask the question why Clyde thinks this is a good example of models not reproducing reality...
58159. Bob Loblaw at 13:21 PM on 1 June 2012
       Models are unreliable
       Re: Clyde's definition of "computer modeller" and pointers to blogs that purportedly show model weaknesses. You have utterly failed to provide a useful definition of "computer modeller". It is the equivalent of telling me that a "frobnitz gleabinator" is someone who can "gleabinate a frobnitz". As for your link to JoNova's site: I see no point in going to a blog written by someone with no basic understanding of climatology. Others have already posted critiques of that information, and I see no need to add to them now. As I mentioned in my earlier request, please provide links to real scientific literature (Pielke Sr. also doesn't count in this area of expertise), or at least web sites where real scientific information is presented. When you post such links, please provide at least a short description (in your own words) of just what it is I should expect to find there. Now, to continue this discussion, can you please provide me with answers to the following questions that I have already posed to you: 1) What is your definition of a "computer modeler"? 2) On what basis do you claim that any particular "climatology expert" is not knowledgeable about computer modeling, and how would this affect the work that they are doing? 3)What else would I need in my background to convince you that I know enough about "computer modeling"? (My background was presented in this comment.)
58160. Bob Loblaw at 13:05 PM on 1 June 2012
       Models are unreliable
       Re: Clyde's mention of Pielke Sr. and his "challenge": I have no interest in going to Pielke's web site to find out what sort of "challenge" he has issued. He does not allow comments at his blog (last I visited), and I have no interest in trying to "engage" in a one-sided conversation completely in his control. If you wish to place a comment here describing what you understand the challenge to be, then I would be willing to discuss it with you. Pielke Sr. has participated in discussions here at SkS (in some of the blog posts I linked to above), and at Real Climate, and I have debated with him during those discussions. He is free to return here where we can debate on even terms. Since you don't have the time to read the many blog posts I referred you to, I will only suggest that you read this comment of mine on one of those threads, which may explain why I have no respect for Pielke Sr. as a scientist.
58161. Tom Curtis at 12:59 PM on 1 June 2012
       Models are unreliable
       Peter42 @528, the "no dogpiling" rule is designed to avoid people, normally new questioners and/or skeptics, from facing an overwhelming number of responses, thus unintentionally intimidating them. It is certainly not intended to stop side conversations. That said, discussion of Hansen's 1988 predictions are probably off topic here, and should probably be carried across to Dana's excellent post on the topic. My point was not specifically about Hansen's predictions except that Evans completely misrepresents them, either through ignorance where he claimed knowledge, or through willfull deceit; and that therefore reference to his claims has no place in any intelligent discussion of this topic. That said, none of the three scenarios actually occurred, although what actually occurred more closely approximates to B than either other scenario. As Dana says:

       Total Scenario B greenhouse gas radiative forcing from 1984 to 2010 = 1.1 W/m2 The actual greenhouse gas forcing from 1984 to 2010 was approximately 1.06 W/m2 (NASA GISS). Thus the greenhouse gas radiative forcing in Scenario B was too high by about 5%."

       Note that Dana uses a higher value for CO2 concentration than I do, presumably because he got his data from a different source. And yes, there are issues with Evans relative placement of predictions and temperatures (to compare trends, the trend of the different projections should be centered on the trend line of the data at the initial point of the graph to avoid misleading visual cues) and his choice of HadCRUT3 data rather than the more accurate GISTemp or NCDC temperature records.
58162. Bob Loblaw at 12:55 PM on 1 June 2012
       Models are unreliable
       With Jim Eager stepping back and several others chiming in, and another request to avoid dogpiling, for the moment I will restrict my comments to a few direct statements from Clyde. First "Which is harder/more complicated - Writing code for GCM or writing HTML codes for a website? I consider this to be a rather misleading question. It's like asking "which is harder to edit? A book written in English on the growth of multinational corporations, or a book written in German on how to rebuild the engine of a Leopard tank? Both require editing skills, but one benefits from a knowledge of economics and business (and the English language), while the other is easier if you have a detailed understanding of internal combustion engines, tools (and can read and write German). ...but, to answer your question: - given the specifications of the required procedures, any competent programmer can likely implement the algorithms. - the major stumbling block is in determining the algorithms to use, and someone who knows climatology and numerical methods will do better at a GCM, and someone that knows HTML and graphics displays (or whatever the web page is supposed to do) will do better on the web page. In my personal experience (writing web pages by creating HTML in a text editor), the programming skills I developed in my climatology career made HTML a trivial exercise (for relatively simple web pages), and programmers that only know web development do a poor job at any sort of scientific/numerical programming.
58163. scaddenp at 12:53 PM on 1 June 2012
       Models are unreliable
       TC - Jim Eager stepped aside 523 so I thought I would continue. Your excellent post was composed as I was composing mine.
       Moderator Response: TC: It happens. If it were me I was asking you to stand aside, I would step aside in that your post was more directly relevant to Clyde's argument, and you are far more qualified on this topic than I. As it happens, Skywatcher beat you to the punch. I consider my post an aside to rebuff the use of outrageously flawed misinformation.
58164. Tom Curtis at 12:24 PM on 1 June 2012
       IEA CO2 Emissions Update 2011 - the Good News and the Bad
       Sphaerica @15, indeed! If reducing the cost of fossil fuels to third world countries so that their citizens could be lifted out of poverty where in fact our policy objective, there could be few better policies than a wide spread tax on fossil fuels (carbon tax) in first world countries only. By increasing first world costs, it would reduce first world demand and hence prices for those fossil fuels to the third world. Of course, that is not our objective - but neither is it that of those who oppose any suggestion of a carbon tax. Indeed we hear arguments carbon taxes (or emissions trading schemes) on the mutually contradictory grounds that: (a) cheap energy is needed to lift third world citizens out of poverty; and (b) that carbon tax proposals are just a leftist conspiracy to enrich the third world at the expense of the first world, and the United States in particular.
58165. scaddenp at 12:23 PM on 1 June 2012
       Models are unreliable
       (snip) As to JoNova/David Evans misinformation - well look around Skepsci for take downs, (eg hot spot and Evans (snip) Hansen's 1984 model - yes it had sensivity wrong for well understood reasons. see Lessons from past predictions 1981 (and rest of that series for interest). And yes, climate sensitivity is still uncertain, but very unlikely to be less than 2 (or more than 4) - but claiming a past prediction is falsified by data on sensitivity doesnt fly when sensitivity wasnt a robust prediction. (snip)
       Moderator Response: TC: With regret, comments sniped for compliance with the no dogpiling rule. Explicit discussion of Hansen 1988 was retained as being a relevant response to my post,rather than to Clyde. If either of the two current respondents to Clyde with to step aside in your favour, I shall restore your comment (if the html code is working as it should). In that respect I note that your expertise is in computer modelling of petroleum basins.
58166. Peter42 at 12:18 PM on 1 June 2012
       Models are unreliable
       Tom Curtis “How reliable are climate models?” (# 527: 10.38 am 1 June 2012) To Tom Curtis: I’m seeking clarification here, so I hope these question does not fall into the category of “dogpiling” (a term I’m loathe to use, given its homophonic noun alternative). I note your criticism of David Evans’ chart overlaying Hansen’s 1988 predictions with NASA satellite data of global air temperatures, where you demonstrate that the current CO2 level corresponds closely to Hansen’s prediction for Scenario B. Is your main point in that part of your analysis, that Evans should have noted that Scenario B “actually occurred”? Or is there more that I have missed? I’m a bit confused by your paragraph “So, for every gas modeled, the actual 2011 concentration is greater than the projected scenario B concentration, often much greater. In two cases, even the scenario C projected concentration is greater than the actual concentration; yet Evans says that Scenario A emissions is what happened.” Does the four row table above that paragraph, show the 1988 figures used in Hansen’s modelling? My last question is whether there is any issue with the Evans chart of the actual NASA air temperatures – the black line? I’d appreciate your help. Thank you.
58167. Bob Lacatena at 12:12 PM on 1 June 2012
       IEA CO2 Emissions Update 2011 - the Good News and the Bad
       Peter42,

       ...the alleviation of poverty through development for which inexpensive energy is essential.

       This is the latest denier credo, and one of which I've already grown tired, partly because it is so vacuous. No one in the 1st World is working to raise the 3rd World out of poverty by giving them cheap, easy energy. Quite to the contrary, 1st World societies are voracious for oil, while the supply is dwindling, thus continually raising the price and moving it further and further out of the reach of the poor. The cry of "we need cheap fossil fuel energy to help the poor" is garbage. It's just an excuse to conveniently ignore one problem by giving lip service to another, so our society can let people live their lives irresponsibly. This is a lame, lame argument for inaction.
58168. Peter Lang at 12:03 PM on 1 June 2012
       Nordhaus Sets the Record Straight - Climate Mitigation Saves Money
       dana1981 - cumulative.
58169. dana1981 at 11:45 AM on 1 June 2012
       Nordhaus Sets the Record Straight - Climate Mitigation Saves Money
       Peter, I don't see where you get $1345 billion from. In 2050, the biggest difference on chart 5:13 (between the medium global action and high price scenarios) is less than $200 billion.
58170. scaddenp at 11:44 AM on 1 June 2012
       IEA CO2 Emissions Update 2011 - the Good News and the Bad
       "Your argument is then necessarily based on the presumption that humans are largely responsible for current global warming." Yes, because the evidence (as supposed to the misinformation campaign) is overwhelming. Obviously all the natural factors are at work as well, but current warming (post 1975) is human. To propose otherwise requires some evidence which is sorely lacking in the published science. As to cost, relative costs of renewable energy/nuclear power to FF vary enormously on the globe. Here, 75% of electricity is from wind/hydro/geothermal with no subsidies operating. While FF is subsidized, it is very hard to assess competitiveness. Removing all subsidies is the first and necessary step. Will that mean higher energy costs? yes, but lower taxes. Let the market sort it out. After that comes pricing carbon. This is trickier because the adaption costs for not limiting carbon are born not by the emitter but often elsewhere and by another generation. To suggest that someone else pay the true cost of your "cheap" fuel suggests a value to respect rights to me. Suggests for real solutions welcome.
58171. Peter42 at 10:45 AM on 1 June 2012
       IEA CO2 Emissions Update 2011 - the Good News and the Bad
       To Scaddenp (10.46 am 31 May 2012): Thank you for your reflection about the developed nations bearing the costs of “de-carbonising” (which I hope doesn’t include vaporising you and me, given our personal carbon content), while others catch up, a proposal argued strongly on the international stage. It appears to me that you understand the point I was making, that cheap fossil fuels are lifesaving and poverty destroying for under-developed countries, at least for the present. In your first sentence you ask “how about the little problem that changing climate will likely adversely affect the poor in many places much more strongly than those who created the problem in the first place?” Very true, and (-Snip-) Climate change remains a threat, and many contributors to Skeptical Science are quite convinced that a major role is currently played by humans in exacerbating such change. Some others in the community at large, are not so convinced. (My language is deliberately temperate, as the polarisation that occurs through terms such as “deniers” and “alarmists”, inhibits if not prevents objective and constructive discussion.) Your argument is then necessarily based on the presumption that humans are largely responsible for current global warming. I’m not arguing here against that presumption – my main point is that we have a balancing act – and your suggestion about cost-sharing offers a constructive balancing. I have some questions about costs in my reply to CBDunkerson below. To CBDunkerson (22.45 pm 31 May 2012): I have gratefully used solar power for years (hot water systems), and have long thought we should capitalise on wind and sun and other renewable energies. I’ve spent only a little time looking at wind and solar scheme costs, but have been surprised at how much those technologies appear to be subsidised. Your argument is an interesting one, that we need higher costs for fossil-fuel energy, in order to achieve grid-parity with alternative sources. Evidently you share the same presumption as Scaddenp above. I had anticipated that research on solar energy and mass production would have brought costs down far more by now. Perhaps more time is needed in research and improved manufacturing (which must also be included in whole of life costing, as we know). Your second sentence “we do not have to choose between cheap energy and clean energy” does not seem applicable today, and in fact your further informative discussion supports that inapplicability. That is, renewable energy is both cheap and clean, only when the cost of fossil fuels rises to equivalent or greater levels. Am I misunderstanding you?
       Moderator Response: [DB] Off-topic snipped.
58172. Tom Curtis at 10:38 AM on 1 June 2012
       Models are unreliable
       Clyde @552 links to an atrocious analysis by David Evans, who by all accounts (particularly his own) is an expert in computer modeling. Evans criticizes two models which are supposedly representative of IPCC model predictions, the 1988 prediction by Hansen, and the projections by the IPCC First Assessment Report (FAR). He says of them:

       "The climate models have been essentially the same for 30 years now, maintaining roughly the same sensitivity to extra CO2 even while they got more detailed with more computer power."

       Oddly, in the IPCC Third Assessment Report (TAR) we read:

       "IPCC (1990) and the SAR used a radiative forcing of 4.37 Wm-2 for a doubling of CO2 calculated with a simplified expression. Since then several studies, including some using GCMs (Mitchell and Johns, 1997; Ramaswamy and Chen, 1997b; Hansen et al., 1998), have calculated a lower radiative forcing due to CO2 (Pinnock et al., 1995; Roehl et al., 1995; Myhre and Stordal, 1997; Myhre et al., 1998b; Jain et al., 2000). The newer estimates of radiative forcing due to a doubling of CO2 are between 3.5 and 4.1 Wm-2 with the relevant species and various overlaps between greenhouse gases included. The lower forcing in the cited newer studies is due to an accounting of the stratospheric temperature adjustment which was not properly taken into account in the simplified expression used in IPCC (1990) and the SAR (Myhre et al., 1998b). In Myhre et al. (1998b) and Jain et al. (2000), the short-wave forcing due to CO2 is also included, an effect not taken into account in the SAR. The short-wave effect results in a negative forcing contribution for the surface-troposphere system owing to the extra absorption due to CO2 in the stratosphere; however, this effect is relatively small compared to the total radiative forcing (< 5%). The new best estimate based on the published results for the radiative forcing due to a doubling of CO2 is 3.7 Wm-2, which is a reduction of 15% compared to the SAR. The forcing since pre-industrial times in the SAR was estimated to be 1.56 Wm-2; this is now altered to 1.46 Wm-2 in accordance with the discussion above. The overall decrease of about 6% (from 1.56 to 1.46) accounts for the above effect and also accounts for the increase in CO2 concentration since the time period considered in the SAR (the latter effect, by itself, yields an increase in the forcing of about 10%)."

       (My emphasis) A 15% reduction in estimated climate sensitivity is not "roughly the same sensitivity". What is more, early climate models included very few forcings. Evan's comment on that in his video saying (falsely) that they only include CO2, and do not include natural forcings. However models used in the Third and Fourth Assessment reports most certainly used natural forcings, as well as a wide range of anthropogenic forcings. Therefore the claim that "[t]he climate models have been essentially the same for 30 years now" is simply false. More troubling is the graphic Evan's uses: First we have the label indicating the projections dependent on CO2 emissions as if CO2 was the only forcing modeled by Hansen. Indeed, in the video, Evans explicitly states just that, ie, that CO2 was the only modeled forcing. In fact Hansen included five different anthropogenic gases in each model run, so checking just CO2 emissions does not check how well reality conformed with any particular scenario. Far worse, he labels scenario A as "CO2 emissions as actually occurred". What actually occurred, and entirely unpredicted by Hansen, was that the Soviet Union collapsed resulting in a massive reduction of very polluting Soviet Block industry, with a consequent massive reduction of CO2 emissions from the Soviet Block: As a result, current CO2 levels (ignoring seasonal variation) are only 390.5 ppmv, which compares to the 391 ppmv projected by Hansen for 2011 in scenario B. In other words, Evans is claiming that CO2 emissions followed scenario A whereas in reality they have not yet caught up to scenario B. Here are the current concentrations of the other GHG used in Hansen's model: Gas | Actual__ | Hansen (Scenario) ___CH4 | 1810 ppb | 1920 (Scenario C) ___NO2 | _323 ppb | _330 (Scenario B) _CFC11 | _240 ppt | _275 (Scenario C) _CFC12 | _533 ppt | _961 (Scenario B) So, for every gas modeled, the actual 2011 concentration is greater than the projected scenario B concentration, often much greater. In two cases, even the scenario C projected concentration is greater than the actual concentration; yet Evans says that Scenario A emissions is what happened. Given the size of the discrepancies, there are only two possibilities. Either Evans did not bother looking up the data before making his assertion - an assertion he has made repeatedly while strongly emphasizing his expertise. Or he is flat out lying. Seeing Clyde introduced Evans' rubbish to this discussion, he now needs to answer several questions: Do experts make assertions about data which they have not bothered looking up? Do they lie? And why, given that they are supposedly so skeptical, have no fake "skeptics" picked up on these errors and criticized Evans for them? Finally, for a proper analysis of those predictions, I recommend the posts by Dana on Hansen's 1988 predictions, and on the predictions of the First Assessment Report. I don't think Dana claims to be an expert on climate modeling, but at least he treats the data with integrity.
       Moderator Response:

       TC: I again request that we avoid dogpiling. As Jim Eager has withdrawn, I ask that only Bob Loblaw and Skywatcher, as people with directly relevant experience to the topic make further responses to him. I ask that posters forgive my slight hypocrisy also responding, but I am sure you will understand my distaste for the introduction of Evans' effort in what hopes to be a conversation guided by evidence and aiming at truth. In the event, future responses to Clyde other than by Bob Loblaw or Skywatcher will be deleted as dogpiling, unless either withdraws, in which case Muoncounter can take up the cudgels.

       [DB] Lest some think that this is moderation by fiat by TC, this action has the full support of the moderation staff of SkS. TC has merely implemented a jointly discussed and approved action.

58173. Martin A at 10:22 AM on 1 June 2012
       CO2 has a short residence time
       DM: Yes, thank you, you are right, nonlinearity is not required for (adjustment time)>(residence time) for your model. I guess that your model, though linear itself, approximates a nonlinear relation between the atmospheric CO2 concentration and rate of diffusion from atmosphere to environment better than the linear relation assumed in ES09. I think I should have said that for (adjustment time) > (residence time) then dC/dt cannot be directly proportional to C ie if you have dC/dt = const.V + F_i then you will get (adjustment time)=(residence time). I'm working on using the Mauna Loa data to reproduce your result and to get an understanding of why your model is a better representation of reality than ES09.
58174. Tony O at 09:28 AM on 1 June 2012
       Ian Plimer Pens Aussie Geologist Gish Gallop #2 of the Week
       Have you noticed how every business failure every decision to off shore production or services is blamed on the carbon tax. This seems particulary so in Sydney, not so bad in Perth.
58175. Peter Lang at 09:23 AM on 1 June 2012
       Nordhaus Sets the Record Straight - Climate Mitigation Saves Money
       dana1981 - my apologies; my second link should have pointed readers to: the two comments on 4 May. Below is an expanded version. Benefit to cost ratio of the Australian CO2 pricing scheme to 2050 In an interesting exchange between Roger W. Cohen, William Happer and Richard Lindzen, and reply by William D. Nordhaus on “The New York Review of Books” here Professor William Nordhaus (hereafter WN) said: “The final part of the response of CHL comes back to the economics of climate change and public policy. They make two major points: that the difference between acting now and doing nothing for fifty years is “insignificant economically or climatologically,” and that the policy questions are dominated by major uncertainties. Is the difference between acting now and waiting fifty years indeed “insignificant economically”? Given the importance attached to this question, I recalculated this figure using the latest published model. When put in 2012 prices, the loss is calculated as $3.5 trillion, and the spreadsheet is available on the Web for those who would like to check the calculations themselves. If, indeed, the climate skeptics think this is an insignificant number, they should not object to spending much smaller sums for slowing climate change starting now.” Particularly note this bit:

       When put in 2012 prices, the loss is calculated as $3.5 trillion, …. If, indeed, the climate skeptics think this is an insignificant number, they should not object to spending much smaller sums for slowing climate change starting now.

       I am surprised that WN says the $3.5 trillion is a significant number, given that it is cumulative to 2050 and is for the whole world. I am also surprised that WN says skeptics “should not object to spending much smaller sums for slowing climate change starting now.” I consider the Australian situation and calculate the costs to achieve the Australian share of the $3.5 trillion reduction in climate damages would be around nine times greater than Australia’s share of the estimated $3.5 trillion saving. Here is how I did my calculations. I converted the estimated $3.5 trillion world damages avoided to the Australian proportion on the basis of Australia’s share of world GDP, i.e. 1.17%. So Australia’s share of damages avoided is 1.17% x $3.5 trillion = $41 billion. That is the cumulative damages avoided by Australia to 2050. It assumes an optimal CO2 price, the whole world implements the CO2 price in unison, and an economically efficient system is implemented across the whole world. It also assumes Australia’s share of world GDP remains constant. The Australian Treasury estimated the loss of GDP that our legislated CO2 tax and ETS will cause. [ However, it seems they may have underestimated because they, apparently, have not estimated the compliance cost]. The cumulative loss of GDP to 2050 is $1,345 billion (undiscounted) (Chart 5:13), or $390 billion discounted at 4.34%, which I believe is the discount rate that is the default in RICE (2012) and gives the value of $3.5 trillion quoted by WN. If my calculations are correct, the benefit, to Australia, of the optimum CO2 tax rate (if the world implements an economically efficient CO2 pricing scheme in unison) would be $41 billion and the cost (reduced GDP) would be $390 billion. Therefore, the benefit to cost ratio is 0.11. [benefit/cost should be greater than 1 for the policy to be justified] . Therefore, I do not understand WN’s statement that “[sceptics] should not object to spending much smaller sums for slowing climate change starting now.” My calculations suggest we would spend nine times greater sums, not smaller sums, to achieve the benefits estimated by WN.
58176. skywatcher at 09:18 AM on 1 June 2012
       Models are unreliable
       Clyde, so far, your case is entirely evidence-free regarding: 1: what you regard as a specialist computer modeller? 2: what expertise such a person would have that it is impossible for a climate modeller to acquire? (who will spend most of their research life from at least PhD onwards writing code, usually beginning with a background in physics or earth/environmental science). 3: why somebody who has spent many years, perhaps even decades, coding climate models would not then be an expert in coding? Are there some secrets that they never let out of the computer science department? I've coded small climate models, and I've worked with a number of people who professionally code much more sophisticated ice sheet and climate models - you baselessly insult their intelligence and hard-won expertise. I've seen physicists attempting to code ice sheet models and making a pigs ear of it in the first instance because they didn't have the understanding of earth systems, glacier dynamics and climate to make such a thing realistic (they learned, gradually!). I've seen the reverse - the physics expertise is equally hard-won. I have not seen a computer scientist even have a go because they would need to get to grips with two major things: how a climate system works, and the mathematics of the thermodynamics/mechanics required to calculate components of the model. Quite how you think the pure coder who can write very tidy Fortran/C++/Python could do this better than the existing experts is remarkable. It is much easier to begin with an understanding of climate and physics, and graduate onto writing computer code, which is fundamentally not that difficult to do, than the alternative.
58177. Alex C at 08:53 AM on 1 June 2012
       Modeled and Observed Ocean Heat Content - Is There a Discrepancy?
       Bob Tisdale: I've been looking through the interwebs to see if I could find anything on the GISS Model ER simulations past 2003 to see whether or not the straight-line extrapolation is an accurate estimation of what the models actually said would happen. I came across a post at Troy's, you commented there so I think you might be familiar: http://troyca.wordpress.com/2011/10/06/giss-er-and-ocean-heat-content/ I think that, in the absence of a more formal showing of the model output (and since I don't see any reason to suspect Troy has done anything wrong in his plotting), this should serve as a useful tool for all of us to see how the models predicted the past decade. The straight-line extrapolation that you use (and RealClimate and others) appears to be a pretty accurate estimation of the model output over the last decade, so I don't see any reason to stand by the opinion that you're misrepresenting the model output. However, the model output starting after 2004 does not appear to actually be based on known data, but the A1B scenario specifications. To compare the model output to the observations makes the assumption that our climate system has seen comparable forcing to A1B, which isn't obvious is the case since again we had an increased aerosol effect, a prolonged solar minimum through 2008/2009, for instance. I can't see how the model's A1B output is any better than the linear extrapolation, because it is just as physically unrepresentative of the past decade. Feedback on this of course appreciated, from anyone that might have anything else to add on to this as well.
58178. Alex C at 07:37 AM on 1 June 2012
       Modeled and Observed Ocean Heat Content - Is There a Discrepancy?
       Bob Tisdale: Your graph of the tropical Pacific is not accurate, and I find it strange you would think anyone would think that two different datasets would have *identical* anomalies, even taking into account the guaranteed offset since the 0-2000m dataset must necessarily have higher OHC than 0-700m. Where are you getting your data? I have obtained it from the exact same source you referenced me to at WUWT, here: 700m: http://climexp.knmi.nl/data/ien3_ohc700_120-280E_-24-24N_n.dat 2000m: http://climexp.knmi.nl/data/ien3_ohc2000_120-280E_-24-24N_n.dat These are the two datasets plotted against each other over the time frame you have given. I zeroed both to a 1970-1995 baseline. http://i47.tinypic.com/2aflv0h.png 0-700 is in red, 0-2000 is in blue. They are not the same datasets, contrary to what you posted. You posted the exact same data overlaid, I'm curious why.
58179. muoncounter at 07:27 AM on 1 June 2012
       Models are unreliable
       Clyde#521: "I might have more trust in the models if i knew the scientist running them had expertise in computer modeling." How do you know they do not have such expertise - or do not have available those who do? It would appear you missed this model quality-check from the Intermediate version of this argument. If your argument with computer models is that 'scientists don't know how to program,' that song is old and tired. I suggest you look here or here. If your argument is 'you can't trust a computer model,' I suggest you look here to see how computer models impact medicine and here to see how pervasive computer models are. If you distrust modeling so much, be prepared to give up a lot of what we now take for granted as part of our 'quality of life.'
58180. scaddenp at 07:15 AM on 1 June 2012
       Dear Heartland, Stop using Arthur Robinson's Trick to Hide the Incline
       Past temperatures have to be derived from proxy data of various kinds. Historical (pre-thermometer) records are of much use for evaluating the significance of these proxies. ie is the temperature record in proxy consistent with historical accounts or is it too localised to be of use). See for example Ljungquist 2010 for proxies.
58181. Rob Painting at 06:08 AM on 1 June 2012
       Modeled and Observed Ocean Heat Content - Is There a Discrepancy?
       Alby @30 - Yes there is a great deal of difference between the Levitus and Lyman methodologies. This was discussed in one of Lyman's papers, and touched upon in Von Schuckmann & Le Traon (2011). Levitus infills missing data with the average, whereas Lyman interpolates from adjacent measurements. Levitus' method will tend to underestimate changes as the anomalies relax toward zero. AFAIK there is no agreement yet on which is the better approach.
58182. DSL at 05:46 AM on 1 June 2012
       Models are unreliable
       Clyde, your (now deleted) Arctic comment has been responded to on a more appropriate thread.
58183. DSL at 05:42 AM on 1 June 2012
       Arctic icemelt is a natural cycle
       I'd invite Clyde to Neven's site, where such issues are the meat of daily discussion and where offering one's personal models is encouraged. The daily graphs page is a good bookmark as well. You're right, though: you'll get hammered for not addressing the carefully measured data and instead relying on a relative handful of newspaper reports, many that report from small areas of the Arctic. Note that Zwally said "at this rate," and if he was thinking of the drop from 2006 to 2007 that's certainly true: a drop of 1.5 million sq km in minimum extent per year would definitely have the summer free of ice by 2012. However, "at this rate" is the simplest model, and I'm sure that Zwally would never bet on it--not in 2007. As extreme as the 2007 extent was, it's been beat by 2011, and 2012, after a bizarre spring, is now racing down at a rate that may be unprecedented over the last 30 years. Volume set a record low in 2011 as well, and 2012 is tracking almost dead on top of 2011.
58184. Jim Eager at 05:37 AM on 1 June 2012
       Models are unreliable
       Well, since Clyde refuses to acknowledge all the things that climate models have gotten right, and that they are useful for understanding how climate behaves in the present and will behave in the future, or that scientists can even be competent climate modelers, and is now directing people to Jo Nova's site to support his argument, as per the moderator's request I hereby defer my right of reply to anyone else wishing to waste their time continuing the discussion with him.
58185. Rob Painting at 05:25 AM on 1 June 2012
       Modeled and Observed Ocean Heat Content - Is There a Discrepancy?
       Bob Tisdale@ 28 - No I did not miss either of those points, in fact upcoming posts make those issues very explicit because they help elucidate the observations. The most significant effect human pollution aerosols have is their influence on cloud formation processes. And yes, I fully expect the global brightening trend over the 1990's played a part in the faster rate of ocean warming over that interval. It seems to be consistent with both the observations and our physics-based understanding. For instance, how does one explain the near-linear trend in sea level rise over the last two decades? The contribution of meltwater from both the Greenland and Antarctic icesheets has accelerated yet sea level rise hasn't - this implies the thermal component (ocean warming) has slowed when compared to the decade prior to 2003. I, for one, do have reservations about the ocean models, but it's for other reasons. They are after all imperfect, but useful, approximations of the real world.
58186. Clyde at 05:21 AM on 1 June 2012
       Models are unreliable
       Sorry about the post above. More evidence the computer models are not good at predicting future climate change. One minor "type O" & things come out wrong.
58187. Clyde at 05:09 AM on 1 June 2012
       Models are unreliable
       Jim Eager 516 I guessing if you had a peer reviewed paper you would give credit to all who helped in writing of the paper IE any folks who had been computer modelers by trade. My definition of a computer modeler would be somebody who's primary job was making computer models. I might have more trust in the models if i knew the scientist running them had expertise in computer modeling. So yes i would prefer the scientist give the data they want modeled to somebody who's primary job is computer modelling. No i wouldn't bet my life on computer model predictions. My using the betting of life is not a good thing to do IMO. My apologies to all. (-Snip-)
       Moderator Response: [DB] Off-topic snipped.
58188. Clyde at 05:04 AM on 1 June 2012
       Models are unreliable
       Bob Loblaw 512 I have no idea if Pielke Sr is right or wrong when he issued the challenge. All i know is if anybody has taken him up on it he hasn't posted it..at least not yet. The link below is not the challenge (I'll try to find it later) but has several peer reviewed papers casting doubt on predicting future climate based on computer models. Read more here. I've read articles that Kevin Trenberth has a theory where the "missing heat" went. Another example of the models not being very accurate. How can you just a model[s] that missed 10 years of heat? My first try with the hyperlink deal. Hoping this works.
58189. Clyde at 05:01 AM on 1 June 2012
       Models are unreliable
       I appreciate all the help everybody is giving. I can't reply to everybody. Thanks to the moderator who has ask the "dogpiling" be kept down. Bob Loblaw 510 Which is harder/more complicated - Writing code for GCM or writing HTML codes for a website?
58190. Albatross at 03:54 AM on 1 June 2012
       Modeled and Observed Ocean Heat Content - Is There a Discrepancy?
       Daniel, Thank you very much! I'm almost too scared to ask how you did that ;)
58191. Albatross at 03:53 AM on 1 June 2012
       Modeled and Observed Ocean Heat Content - Is There a Discrepancy?
       Hi Rob @25, To continue from where the post went missing: ....and that is ignoring for the moment the dicey practise of making sweeping generalizations (as certain contrarians are doing) based on the analysis of less than 10 years of data when we are dealing with an inherently noisy system. Even though the model output after 2003 has not been using the most up to date forcings, the descrepancies are actually not nearly as large as claimed by some. The amount of disagreement also depends on the depth range being considered, and which analysis one is using whether it be the method of Lyman et al. (2010), Levitus et al. (2012) or Hamon et al. (2012). Yet, the "skeptics" choose to take one analysis product as "truth". Regardless, this strawman argument that have been getting some people so excited may very likely be moot once the models are run using the latest forcings for CMIP5 (i.e., the model runs for the next IPCC asessment report). Not only that, but it seems that this red herring that "skeptics" are floating is to try and distract people from the fact that the climate system is continuing to accumulate heat. I am also very curious why contrarians are so reluctant to use the 0-2000 m data from Levitus et al. (2012) [which incorporates the ARGO data] when they are freely available on the web, [Source]
       Moderator Response: [DB] I was able to restore your missing portion of your previous comment.
58192. Tom Smerling at 02:56 AM on 1 June 2012
       Richard Alley's Air Force Ostrich
       Moving right along.... These EOM clips starring Richard Alley are real gems. This is the "state of the art" for climate communication. Nobody says it better. Bloggers: Upon request, this week EOM enabled copying of the embed codes from their YouTube page. So now you can copy the embed code for any of EOM's 67 short clips from EOM's YoutTube channel, and simply paste the code directly into your blog post.
58193. Albatross at 02:50 AM on 1 June 2012
       Modeled and Observed Ocean Heat Content - Is There a Discrepancy?
       Rob @25, Gavin Schmidt did show those model data through 2010 in a presentation, but those model output data after 2003 were not generated using the updated forcings. Note how well the GISS-EH model does for most of the record (up until 2003), but that is when it was run using the best estimates of the actual forcings for 1880-2003. So the model output after 2003 did not take into consideration the recent extended and deep solar minimum, nor did it take into account the significant increase in aerosol loading, for example. And that is ignoring for the moment the dicey practise of making sweeping generalizations (as certain contrarians are doing) based on the analysis of
       Moderator Response:

       [Albatross] Somehow the second half of my post disappeared. I'll do my best to reproduce the original.

       [DB] Text and graphic restored. And don't ask how. ;)

58194. Bob Tisdale at 02:44 AM on 1 June 2012
       Modeled and Observed Ocean Heat Content - Is There a Discrepancy?
       Sphaerica: Thanks for the link. Rob Painting: Thanks for suggesting I look into Hatzianastassiou et al (2012). Somehow you missed the fact that the aerosol contribution to surface solar radiation (the SSR in the graphs you posted) was considered by the authors to be secondary to clouds. And you also missed the fact that the authors concluded it was a two way street, with the increase in surface solar radiation during the 1990s contributing to the warming then.
       Moderator Response:

       [DB] Somehow you missed the link to the Updated Comments Policy, with its strictures against inflammatory tone being especially relevant.

       Note that dialogue here is best-considered a two-way street, with an observance of the Comments Policy being given more than a passing nod.

58195. dana1981 at 02:08 AM on 1 June 2012
       Nordhaus Sets the Record Straight - Climate Mitigation Saves Money
       Peter Lang - I see no sources for your numbers. If you wish to be taken seriously, you have to provide sources for your figures which can be back-checked.
58196. Bob Lacatena at 02:05 AM on 1 June 2012
       Modeled and Observed Ocean Heat Content - Is There a Discrepancy?
       Bob, See here (correct name is N. Hatzianastassiou)
58197. Bob Tisdale at 00:00 AM on 1 June 2012
       Modeled and Observed Ocean Heat Content - Is There a Discrepancy?
       Rob Painting: Regarding your 22:59 PM on 31 May, 2012 comment, Glenn Tamblyn’s comment at WUWT reflects his lack of understanding of the subject at hand. My reply to him is here: http://wattsupwiththat.com/2012/05/30/dana-nuticellis-skeptical-science-ohc-grapple-down-for-the-count/#comment-997765 It reads: Glenn Tamblyn says: “When in fact you have no idea what the GISS model predicts for 2004-2012. They haven’t modelled it. you are simply assuming that if they were run for that latter period they would predict exactly the same trend as they did for the previous decade.” Of course they have modeled it as part of the models they submitted to the CMIP3 archive. Gavin simply elects not to include it in his presentation at RealClimate. Why? His answer from this post: http://www.realclimate.org/index.php/archives/2009/12/updates-to-model-data-comparisons/ There he writes, “Another figure worth updating is the comparison of the ocean heat content (OHC) changes in the models compared to the latest data from NODC. Unfortunately, I don’t have the post-2003 model output handy, but the comparison between the 3-monthly data (to the end of Sep) and annual data versus the model output is still useful.” And he continues, “(Note, that I’m not quite sure how this comparison should be baselined. The models are simply the difference from the control, while the observations are ‘as is’ from NOAA). I have linearly extended the ensemble mean model values for the post 2003 period (using a regression from 1993-2002) to get a rough sense of where those runs could have gone.” And what does the GISS Model-ER mean look like through 2010? It looks like a trend extrapolated from 1993-2003: http://i52.tinypic.com/3536rsm.jpg Refer to the discussion of Figure 3 in my post here: http://bobtisdale.wordpress.com/2011/06/14/giss-ohc-model-trends-one-question-answered-another-uncovered/ Rob, with respect to the graphs you provided, do you have a link to the paper? Google provides zero returns for the name Hatzianastissou.
58198. Rob Painting at 22:59 PM on 31 May 2012
       Modeled and Observed Ocean Heat Content - Is There a Discrepancy?
       Bob, Glenn Tamblyn has pointed out perhaps the most egregious flaw in your posts. You complain that the models don't match reality over the period in question, and yet you present no evidence of the GISS simulations over that period. Consider for a moment the global aerosol trend for much of that interval, from Hatzianastissou (2011): A large dimming is apparent in the Southern Hemisphere, which of course is predominately ocean. If these aerosol estimates are the basis for GISS modeling over the period in question, we'd expect a noticeably slower rate of ocean warming in the upper 700 metres in the model runs. Thus far you seem to be arguing a strawman.
58199. CBDunkerson at 22:45 PM on 31 May 2012
       IEA CO2 Emissions Update 2011 - the Good News and the Bad
       Peter42, unfortunately the situation you describe is a false dilemma. That is, we do not have to choose between cheap energy and clean energy. The dramatic drop in solar power costs during the brief window while it looked like the age of cheap fossil fuel power was ending proves that energy which is cheap and clean is entirely possible. We could have had current solar technology decades ago if R&D had been adequately funded... but there was no political will to do so because a cheap alternative already existed. The problem now is that we've gone from a situation where global 'grid parity' for solar power seemed inevitable before the end of the current decade to one where we again have an abundant cheap alternative and thus could potentially stop pursuing further improvements in solar power. On the up side there are some places where solar grid parity has already been achieved and which cheap shale gas won't impact. Hawaii, for example, has historically gotten most of its electricity from oil because coal and natural gas are too expensive to ship over the ocean. Using oil for electricity generation is fairly expensive and Hawaii is a sunny place... so solar power dropped below grid prices in Hawaii a couple of years ago. A new boom in shale gas won't change that. So Hawaii and various other places where solar is already below grid parity will likely continue transitioning over to solar power. Hopefully that ongoing local development will be enough to continue driving down costs to the point that solar costs become cheaper than fossil fuels globally.
58200. Bob Tisdale at 20:55 PM on 31 May 2012
       Modeled and Observed Ocean Heat Content - Is There a Discrepancy?
       Tom Curtis says at 09:16 AM on 31 May, 2012: “The graph was produced by Bob Tisdale, whose analysis is normally massively flawed, so I am not providing a link.” You presented obsolete NODC OHC data from a 3-year-old May 13, 2009 post. The NODC has updated their dataset twice since then. Is there any reason you presented obsolete data? Also, my website requests that you provide a link to the post when using a graph. You failed to do that. (snipped link to graphs no longer displayed) Your claim that my “analysis is normally massively flawed” is baseless. And you’ve expressed your misunderstandings in the rest of your comment. The variations in tropical Pacific OHC are in fact a function of ENSO, but there is no difference in tropical Pacific OHC for depths of 0-700m and 0-2000m: http://i46.tinypic.com/dbi51j.jpg The data contradicts your claim of “greater conduction of water to the depths, and hence an overall cooling of the surface waters (0-700 meters).” BTW, 0-700 meters is not the surface. And did you mean subducted? Also, you must not have looked very hard for a paper that discusses the additional variability of the North Atlantic OHC. Lozier et al (2008) “The Spatial Pattern and Mechanisms of Heat-Content Change in the North Atlantic” identifies the NAO as the driver of decadal North Atlantic OHC variability. Link: http://www.sciencemag.org/cgi/content/abstract/319/5864/800?rss=1 Have a nice day!
       Moderator Response: TC: Link snipped as the graphs have been removed and the link is no longer required for copyright reasons.

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