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Comments 85201 to 85250:

85201. Charlie A at 04:42 AM on 24 May 2011
       Roy Spencer’s Latest Silver Bullet
       Albatross -- as shown in the table 8.2 linked in your post #22, the Transient Climate Response for the various models averages about 1.8C, and for GISS-E is listed as 1.5C. Note that the TCR is higher than the short term transient sensitivity, as the TCR is defined as the model output with a 1% increase of GHG each year, averaged over the 20 year span centered on the point where the GHG have doubled. Since doubling at 1% rate takes 70 years, the 20 year averaging period is from year 60 to year 80. Now look again at my comment #9 that seems to have caused such great angst. All I said saying is that the short (1955-2010 is ONLY 55 years) period of the OHC over which Spencer calculated sensitivity means that his calculated 1.3C for doubling sensitivity is not surprising since it consistent with the various models used in AR4, including GISS E which has short term sensitivity of 1.2C/doubling at 5 years and 1.8C/doubling at 100 years. (or perhaps 1.1C at 5 and 1.6C/doubling at 100 years if 2.7C/doubling is used as equilibrium sensitivity rather than the 3.0 that I have more recently). Somehow, my saying "Spencer's 1.3C for doubling CO2 doesn't matter because it isn't all that different than GISS E sensitivity" gets treated as a heretical statement. Strange.
85202. Eric the Red at 04:17 AM on 24 May 2011
       Carter Confusion #2: Green Jobs
       Am I reading this correctly? That renewable energy has higher labor costs per unit of energy than coal or gas?
       Response:

       [dana1981] Possibly, depending on the costs per job.  But renewable energy is lower cost on other fronts (i.e. fuel and transportation)

85203. Eric the Red at 04:06 AM on 24 May 2011
       UQ Physics Colloquium this Friday: Communicating Climate Science and Countering Disinformation
       I think it would help to communicate the realities of climate change if references to the Doran study were removed. According to the study 82% of participants thought that human activities (without specifying which) were a significant factor in changing global temperatures. CO2 was never mentioned. In fact among climatologists, the number was only 88% (not 97%), and nowhere did it saw they were convinced. Part of the difficulty among those of us who which to communicate climate change effectively is overcoming these types of errors which have been used against us as examples of "exaggerations." It is difficult to counter disinformation from our adversaries, but it is even more difficult when the perpretrators are our own.
85204. Bob Lacatena at 04:05 AM on 24 May 2011
       Skeptical Science Educates My Students
       Phila, Yes. My main point is that Pirate's predilection for believing in his own version of the science, rather than science's version of the science, is that as a science teacher he is then imposing his ignorance on pupil after pupil, year after year. He needs to hold himself to a much higher standard. Being part of the crowd (and jumping off the bridge because Johnny did it, too) is unacceptable. I don't care how many thousands of people he thinks believe the GW is natually caused. It doesn't matter. He's a science teacher. If he's going to express any opinion or knowledge of the subject whatsoever to his students, he owes it to them, his school, his school's townspeople, and all of the rest of us to understand what he's talking about before he says a word. And if what he believes is at odds with the published science, the various science organizations and academies around the globe, the science faculty at a local university, etc... then he better be dang sure that his Galileo complex is well-earned... because otherwise, he's the Spanish Inquisition imposing his own personal views of science (no matter how popularly they may or may not be shared by the less educated around him) on his pupils.
85205. Albatross at 03:07 AM on 24 May 2011
       Roy Spencer’s Latest Silver Bullet
       All, Regarding this claim made by Charlie @20, "If we accept Albatross's characterization of GISS-E model as having 2.7C CO2 doubling sensitivity" Had the contrarian bothered to follow the link that I had provided they would have seen that it was not my characterization but a link to RealClimate, which includes a comment by Dr. Gavin Schmidt (who works extensively with the model) concerning the model's climate sensitivity, it also made reference to Table 8.2 in the IPCC AR4 report. Thanks Sphaerica @21. Good points. Now moving on.
85206. Phila at 02:52 AM on 24 May 2011
       Skeptical Science Educates My Students
       Harry Seaward: So, if a kid comes to me and has a strong fundamentalist religious background and believes in Creationism - I tell them fine, but you still have to demonstrate your case to me and the class during your required presentation in a logical, scientific manner. Interesting. Could you give us an example of a "logical, scientific" argument for the Earth being, say, 6,000 years old? Sphaerica: Comment less and study more, pirate. Pirate was trumpeting his informal survey of the faculty at his unnamed school months ago; despite all the resources for self-education he's fortunate enough to have, he still seems to feel that his casual exercise trumps actual scientific data. It's kind of sad to see someone with so many opportunities to learn, and so little interest in making the most of them. To me, what Harry and Pirate both indicate is that too many Americans apply a sort of libertarian property-rights doctrine to personal opinion, so that correction becomes something akin to trespassing or theft. In the real world, of course, some people are actually just wrong, and the "willful" part of willful ignorance is the problem, rather than a mitigating factor.
85207. curiouspa at 02:52 AM on 24 May 2011
       Carter Confusion #2: Green Jobs
       I should change my moniker. It generates an immediate negative response. Consider me questioning rather than skeptic/denier. I have issues with the numbers quoted from the UNEP study. When I read the study, it lists the number of jobs existing in 2007, not necessarily created in the past 7 years. Also, the number of direct jobs is 89,000. There are 99,000 indirect jobs, and who knows what that means. This is an example of shoddy reporting/use of statistics. I suspect that Calzada has a similar bias the other way in the numbers he quotes, and for all we know, may just make them up. However, it is always important to remember our own personal bias when quoting statistics. I believe this report was incorrectly used.
       Response:

       [dana1981] My mistake (not the UNEP's), thanks for catching that.  I've updated the post and rebuttal accordingly.

85208. ClimateWatcher at 02:49 AM on 24 May 2011
       Carter Confusion #2: Green Jobs
       So let G = the number of green jobs. Let C = the number of carbon jobs. If we replaced all carbon jobs with green jobs, and they were equivalent, then G = C This would mean no net increase in jobs. Say that G > C Since employee costs are typically the highest cost of business, this would mean that green energy would cost more. Sat that G < C then green energy would be more economical, thanks to lower employment costs, but probably not a big jobs benefit ( similar to the ongoing automation and computerization of our economies)
       Response:

       [dana1981] No.  You're ignoring all non-labor costs.  As noted in the article, fossil fuels have higher transportation costs, just as one example.

85209. Bob Lacatena at 02:49 AM on 24 May 2011
       Roy Spencer’s Latest Silver Bullet
       20, Charlie A, You included the set up (i.e slow GISS ModelE-R response to forcing), but left out the core of Hansen's paper:

       Below we argue that the real world response function is faster than that of modelE-R. We also suggest that most global climate models are similarly too sluggish in their response to a climate forcing and that this has important implications for anticipated climate change.

       Then later:

       We believe, for several reasons, that the GISS modelE-R response function in Figs. 7 and 8a is slower than the climate response function of the real world. First, the ocean model mixes too rapidly into the deep Southern Ocean, as judged by comparison to observed transient tracers such as chlorofluorocarbons (CFCs) (Romanou and Marshall, private communication, paper in preparation). Second, the ocean thermocline at lower latitudes is driven too deep by excessive downward transport of heat, as judged by comparison with observed ocean temperature (Levitus and Boyer, 1994). Third, the model's second-order finite differencing scheme and parameterizations for turbulent mixing are excessively diffusive, as judged by comparison with relevant observations and LES (large eddy simulation) models (Canuto et al., 2010).

       At the same time, the focus of Held's paper is merely to separate and distinguish fast from slow acting responses to climate change. It assumes no predicative capacity whatsoever, and is based on a single model with known and quantifiable limitations. His main takeaway is our presumed ability to correctly estimate/measure the level of fast-acting responses in short time frames (the steep rise), un-muddled by slow-acting factors (the more shallow plateau). The ultimate fact, however, is that it is very early on in the game to be assuming that we know how fast things will happen. But if it does take as long as predicted, then that's very, very bad, because it means we might not make any effort to mitigate our CO₂ levels whatsoever, and it will be many generations before the world discovers how very badly we've fouled up the climate. Imagine that climate sensitivity turns out to be 6˚C, and people 300 years from now have to live with a 3˚C increase, knowing that a catastrophic additional 3˚C is "in the pipeline." On the surface, it appears to be a good argument for business as usual, when to any moral person it is an argument for the opposite. But in the end, both papers are complex and nuanced. They're perfect papers from which to cherry pick scraps of info that can easily be misunderstood.
85210. CBDunkerson at 02:10 AM on 24 May 2011
       Shapiro et al. – a New Solar Reconstruction
       Sphaerica, even if we make a lengthy list of assumptions which Ken didn't specify (e.g. no change in aerosol particulates, no ozone deterioration, no 'land use' changes, et cetera) there is still no single answer. The TSI needed to maintain any specific 'climate state' (and note that the 'climate state' at the start of the industrial revolution was something called 'the Little Ice Age') would be constantly increasing for thousands of years as the cooling from the orbital forcing grew greater. So, in short, no Ken's question cannot be answered... because it is founded on his false belief that "the variation in TSI is the only 'external' forcing". Given the existence of other forcings, which are changing over time, it is completely impossible to cite a single TSI value which would maintain a stable climate on an ongoing basis. He is looking for a fixed TSI value which keeps the climate stable and no such number exists.
85211. dhogaza at 02:00 AM on 24 May 2011
       Carter Confusion #1: Anthropogenic Warming
       Jonicol: "I want to understand the characteristics of its absorption in various molecular bands and the physical processes involved in the redistribution of that energy through intermolecular collisions and subsequent convection upwards of that energy. " Look deep into the exit pupil of a CO2 laser, turn it on, and get back to us afterwards if you want to argue that physicists don't understand the physics ...
85212. Charlie A at 01:56 AM on 24 May 2011
       Roy Spencer’s Latest Silver Bullet
       One more accusation of misrepresentation to discuss: At the end of post #10, Albatross says "The sensitivity of the GISS-E model, at least the last time I looked was +2.7 C. So you misrepresented them too." I assume that this is in response to my #9: "The GISS E model has a sensitivity of only about 1.2C/doubling in the short term (5 years, for example) and only about 1.8C over a century timeframe.", since that is the only mention of GISS E before Albatross's accusation. If we accept Albatross's characterization of GISS-E model as having 2.7C CO2 doubling sensitivity, then my statement "about 1.2C/doubling in the short term (5 years, for example) is equivalent to saying that I expect the climate response function of GISS-E to be 1.2/2.7 = 44% at 5 years and 1.8/2.7= 67% at 100 years. Looking at Hansen's graph of climate response function (copy in post #16, above)the response at 5 years is difficult to read, but it is appears to be just under 40%; and the response at 100 years is slightly less than 60%. It doesn't take any complicated math to see that my comments about 1.2C rise after 5 years and 1.8C after 100 years in response to a 100% step in CO2 corresponds to a GISS-E equilibrium sensitivity of 3.0C for a doubling. My statements about GISS-E in post #8 are further supported by Hansen himself, who in Hansen et al 2011 page 18 says "About 40 percent of the equilibrium response is obtained within five years. This quick response is due to the small effective inertia of continents, but warming over continents is limited by exchange of continental and marine air masses. Even after a century only 60 percent of the equilibrium response has been achieved. Nearly full response requires a millennium." Hmmmm. 40 percent after 5 years. 60 percent after a century. In other words, using the Albatross number of 2.7C/doubling for equilibrium sensitivity, this corresponds to 0.4x2.7=1.1C after 5 years, and 1.6C after 100 years. A bit less than my 1.2 and 1.8C description in #8. Albatross ---- is Hansen misrepresenting the model GISS-E ?? Figure 8a from Hansen 2011 is in post #16 above and shows the climate response for the 0-123 years. To further put things into perspective, here is Figure 7, which shows much more of the slow response, 0 to 2000 years. Held showed response graphs 0-20 years and 0-100 years. Caption from Hansen 2011 for the above figure: "Fig. 7. Fraction of equilibrium surface temperature response versus time in the GISS climate model-ER, based on the 2000 year control run E3 of Hansen et al. (2007a). Forcing was instant doubling of CO2, with fixed ice sheets, vegetation distribution, and other long-lived GHGs."
85213. dana1981 at 01:55 AM on 24 May 2011
       Shapiro et al. – a New Solar Reconstruction
       The thing is, there's no answer to Ken's question. A change in temperature is caused by a change in forcing (for the solar forcing, that's a change in TSI). So assuming all other forcings were zero, you could get equilibrium for any unchanging TSI value, as long as you give the system enough time to reach that equilibrium. Now if you want to calculate equilibrium at a specific given temperature, that's a different story, as Riccardo notes.
85214. Paul D at 01:55 AM on 24 May 2011
       Carter Confusion #2: Green Jobs
       Of course the subject of creating jobs is at cross purposes in the world of free market 'capitalism' politics. On the one hand a typical ideologist has moral views in that they want to do their best to create jobs, on the other hand in order to increase turnover/profits etc. humans are an expensive 'resource'. The two do not work together, which is why you have crashes and booms. It isn't much better in the world of socialism, where a lack of realism and an obsession with protecting jobs hinders change and assumes everyone can consume vast amounts of resources for the sake of social justice. Enter the world of genuine green politics, where there are no guarantees of jobs and no guarantee of increasing wealth. It's realism, facts and a dumping of egos.
85215. Riccardo at 01:40 AM on 24 May 2011
       Shapiro et al. – a New Solar Reconstruction
       Not sure I understand what Ken is asking. He wrote "There must be a theoretical magnitude of TSI which produces an equilibrium ie. above it and the Earth warms -below it and the Earth cools in the absence of all AG forcings. " From this sentence it appears that he's changing cause and effect. I mean, given the magnitude of the TSI (and the other parameters, of course), you can calculate the equilibrium temperature. Doing it the other way around, as Ken is apparently asking, means to give the equilibrium temperature and then calculate the TSI. Am I right Ken?
85216. michael sweet at 01:39 AM on 24 May 2011
       Skeptical Science Educates My Students
       I teach at a public high school in the south and I find it impossible to believe Pirates claim, that the majority of his students at a public school in the US South would believe the theory of evolution. Many students do not believe the Theory of Evolution, but will not state their beliefs to a science teacher they do not trust. A more likely explaination would be that Pirate reaches incorrect conclusions in his informal surveys. Pirate has previously posted his students on line surveys which reflect his (Pirates) opinions, so his claims to be teaching how to think independently are falsified by his students work. As others have pointed out, how can Pirate be claiming to be teaching science when he does not teach what the National Academy of Science says about the subject? Perhaps he has a better authority on science? Who?
85217. Albatross at 01:29 AM on 24 May 2011
       Roy Spencer’s Latest Silver Bullet
       Re Charlie's comments--this is how contrarians try and derail threads. It is funny how "skeptics" and contrarians and those in denial about AGW mock and deride climate models and believe them to be of little or no use, that is until they mistakenly think that such models support low climate sensitivity, transient or otherwise. Spencer is guilty of that, and so it seems are his uncritical supporters. Analyzing the OHC data correct, as Bickmore appears to have done, one obtains an equilibrium climate sensitivity of over 3 C. Quoting Bickmore from the above post: "When I did a least-squares regression, varying the feedback factor to fit the OHC data, I got an a value of 1.1 W/m^2/K, which amounts to an equilibrium climate sensitivity of about 3.4 °C. This is not only within the probable range given by the IPCC, it’s very close to their central estimate of 3 °C. When I adjusted the model to produce an average heat flux of 0.2 W/m^2 for 1955-2010, I got an a value of 0.7 W/m^2/K, i.e., a climate sensitivity of about 5.2 °C, which is above the IPCC’s most likely range. " From Forster and Gregory (2006): "Here, data are combined from the 1985–96 Earth Radiation Budget Experiment (ERBE) with surface temperature change information and estimates of radiative forcing to diagnose the climate sensitivity. Importantly, the estimate is completely independent of climate model results. A climate feedback parameter of 2.3 1.4 W m 2 K 1 is found. This corresponds to a 1.0–4.1-K range for the equilibrium warming due to a doubling of carbon dioxide... " From Gregory et al. (2002) [Source SkS]: "Gregory (2002) used observed interior-ocean temperature changes, surface temperature changes measured since 1860, and estimates of anthropogenic and natural radiative forcing of the climate system to estimate its climate sensitivity. They found: "we obtain a 90% confidence interval, whose lower bound (the 5th percentile) is 1.6 K. The median is 6.1 K, above the canonical range of 1.5–4.5 K; the mode is 2.1 K." From Wigley et al. (2005) who used the short-term response of the climate system to the Pinatubo eruption to estimate climate sensitivity: "After the maximum cooling for low-latitude eruptions the temperature relaxes back toward the initial state with an e-folding time of 29–43 months for sensitivities of 1–4°C equilibrium warming for CO2 doubling. Comparisons of observed and modeled coolings after the eruptions of Agung, El Chichón, and Pinatubo give implied climate sensitivities that are consistent with the Intergovernmental Panel on Climate Change (IPCC) range of 1.5–4.5°C. The cooling associated with Pinatubo appears to require a sensitivity above the IPCC lower bound of 1.5°C, and none of the observed eruption responses rules out a sensitivity above 4.5°C." Enough obfuscation already.
85218. Bob Lacatena at 00:52 AM on 24 May 2011
       Shapiro et al. – a New Solar Reconstruction
       Re my #19 comment, it's also probably not a fair question, in that computing the answer might be a fairly complex exercise. Ken might want to try to derive the answer himself before asking it of others.
85219. Bob Lacatena at 00:51 AM on 24 May 2011
       Shapiro et al. – a New Solar Reconstruction
       I hate to jump to Ken's defense, but I think his question deserves an answer (although it's accompanied by that low, dramatic, foreboding background music that implies that it's the lead in to some sort of pending "gotcha" argument). But all he's basically saying is, given the state of climate variables set prior to industrial times (and I'm assuming that this includes the global mean temp at that time), what TSI would have held the planet in that climate state (barring a new forcing)? Alternately, the same question (and perhaps it's what he meant, it's unclear) could be applied to pre-industrial forcing/feedback variable settings, but current temperatures, although that's sort of a not-possible condition, since the increased temps would continue to change the feedbacks, so there isn't any set single "TSI" setting would not hold the system in equilibrium, because the "feedback forcings" would continue to change. Instead, you'd need a projection of changing TSI values needed to continually counteract the feedbacks and hold the temperature at present levels while the feedbacks stabilize -- which is a totally artificial situation with no application to the real world.
85220. Charlie A at 00:42 AM on 24 May 2011
       Roy Spencer’s Latest Silver Bullet
       Albotross #10 says "You are misrepresenting Held's research, that or you do not understand what his 2010 paper was about." and #11 Stephen Bains says "Charlie A clearly misinterpreted Fig 1 in Held et al 2010, ...Charlie A has misinterpreted this plateau as "equilibrium" despite the authors explicitly stating "the system is clearly still far from equilibrium when it plateaus,..." " Both of those are clear misreadings of my post #10, where I said "Held describes the NOAA GFDL CM2.1 response to a 100% step in CO2 as a rise to 1.5C in 3 or 4 years, then a plateau at that level for 70 years until it starts to slowly rise. Looking at the graphs, I would characterize it more like a 1.4C sensitivity CO2 doubling with a tau of 4 years, followed by 0.35C per hundred years slope for the next few hundred years. " The term "plateau" was used by Held, not me. As I stated in comment #9, I prefer to characterize Fig 1 of Held 2010 (below) as a 1.4C response with 4 year time constant, followed by a 0.35C/100 years slope for a the next few hundred years. The 0.35C/100 years is the long tail, and will further slow after a few centuries. The total rise after many centuries is estimated to be 3.4C for a doubling of CO2. When discussing OHC from 1955 to 2010 and trying to determine sensitivity, we are not diagnosing or estimating the equilibrium sensitivity after centuries (or for GISS E, >2000 years). For this "short" period of only 55 years, climate models have a transient sensitivity that is much lower than the final equilibrium sensitivity. Graphically, this can be seen in Figure 1 of Held et al 2010 (clickable link to full text pdf in my post #9) Note that the above plots are for the full GCM model CM2.1, which has an estimated equilibrium sensitivity of 3.4C for a doubling of CO2. This estimate, by the way, is not found by running full model to equilibrium, but instead is from a 2 box model that emulates the full model.
85221. KR at 00:23 AM on 24 May 2011
       Coral atolls and rising sea levels: That sinking feeling
       Arkadiusz Semczyszak - A fairly minor nitpick (compared to your sourcing of information from WUWT): You posted essentially identical items both here and on this thread. It would be better to post a single item on the more appropriate thread and a link on a related thread if necessary.
85222. Tom Curtis at 23:21 PM on 23 May 2011
       Skeptical Science Educates My Students
       Harry Seaward @85, if a student presents you an assignment arguing for creationism, then it is not possible that they have argued in a logical manner based on the evidence. The evidence for evolution is not weak, and any body who believes the scientific evidence supports creationism has either misrepresented the evidence, cherry picked evidence, or failed to treat the evidence in a logical and scientific manner. Most probably they have done all three. If you cannot detect that, and fail to mark down their selective argumentation, or logical fallacies, you have no place teaching biology. Much the same can be said about teaching climate science. If a student thinks they can show the Earth's temperatures have not risen, that the greenhouse effect does not exist, or that humans have not caused the large recent increase in CO2 levels, they should fail the course for they have either not understood the content, or failed to apply scientific thinking to that content. The should fail for exactly the same reason a student who exits a course on Newtonian dynamics and gravitation should fail if they still think "what comes up must come down" or that there exists an inertial force.
85223. CBDunkerson at 23:21 PM on 23 May 2011
       Shapiro et al. – a New Solar Reconstruction
       Ken, no TSI is not the only long term pre-industrial temperature forcing. The same TSI can have different impacts depending on orbital tilt of the planet... the northern and southern hemisphere have different albedos and different climate feedback cycles. This can be seen in the ~100,000 year glaciation cycle... which is driven by orbital forcing. Fluctuations in TSI forcing over the same time frame are miniscule in comparison. Thus, as Dana indicated, any answer to your question would require definition of the other forcings present. Currently the orbital forcing is producing a slow cooling trend. Thus, without enhanced GHG warming the TSI required to tip the planet into a warming trend would be very high... short term oscillations might occasionally spike high enough, but the long term TSI trend is nowhere close.
85224. Arkadiusz Semczyszak at 23:16 PM on 23 May 2011
       Shapiro et al. – a New Solar Reconstruction
       Dana1981 I congratulate the "revolutionary vigilance" But I hope to talk about SSI and SIM ... Courage ... But it is worth to read my reference - I recommend. Best regards, Yours faithfully A. Semczyszak
85225. Ken Lambert at 23:03 PM on 23 May 2011
       Shapiro et al. – a New Solar Reconstruction
       dana1981 #6 "Ken, your question doesn't really make sense. The Earth will be in equilibrium if the net forcing is zero. Thus the TSI value to keep it in equilibrium depends on all other forcings." If we go back to pre-industrial tmes, all the AG forcings from IPCC AR4 disappear. We are left with climate responses only - S-B Radiative feedback and Water Vapour & Ice Albedo feedbacks. Aside from the occasional big volcano, the variation in TSI is the only 'external' forcing. There must be a theoretical magnitude of TSI which produces an equilibrium ie. above it and the Earth warms -below it and the Earth cools in the absence of all AG forcings.
       Moderator Response: [Dikran Marsupial] The reason that the forcings in AR4 dissapear prior in pre-industrial times is because forcings are defined as changes from pre-industrial (1750) values. Note also that the climate system has a 'momentum', which means that true equilibrium cannot be reached. For a very approximate answer, you could try some simple climate models (such as those in the first few chapters Pierrehumbert's book on planetary climate). Or perhaps average the TSI reconstructions for interglacials (but bear in mind the error bars).
85226. Harry Seaward at 22:58 PM on 23 May 2011
       Skeptical Science Educates My Students
       Dana @ 61 "For example, if I were teaching a biology class..." But, you're not. I am. I have to teach to the curriculum standards because we have state mandated end of course testing. We never see the exam prior to handing it to our students, and the testing is monitored. Now you will just have to take my word on this because I can't supply you the evidence due to privacy concerns, but my students routinely score at the top levels as compared to their peers in our school, district, region and state. As a matter of fact, my Tech Prep students can match up against a lot of College Prep students. However, I am not so concerned about those numbers, as long as when my students leave me at the end of the year knowing how to "think" logically. So, if a kid comes to me and has a strong fundamentalist religious background and believes in Creationism - I tell them fine, but you still have to demonstrate your case to me and the class during your required presentation in a logical, scientific manner. During explorations of various topics, I've yet to see a faith-based site trump a science-based site, but I have seen the reverse happen.
85227. les at 22:52 PM on 23 May 2011
       Skeptical Science Educates My Students
       Don't worry Chris, I'm not typical ... they probably haven't got that much attention overall.
85228. Charlie A at 22:31 PM on 23 May 2011
       Roy Spencer’s Latest Silver Bullet
       @Kevin C --- the expected increase in global average temperature for a doubling of CO2 is generally accepted to be in the 1.2 to 1/5C range when no feedback is assumed. The 1.5 to 4.5C range estimated by IPCC is assuming significant positive feedback. So if the models have relatively small feedback on short timescales (in this case, meaning less than 100 years), then the observations by many that the climate models have a sub-century transient sensitivity of 1.2 to 1.5C is not surprising. To me at least. ------------- Thanks for the link to GISS forcings page. Unfortunately, if you follow the future scenarios link, and then select tropical aerosols,you will see the same "flatline after 1990" set at the bottom of http://data.giss.nasa.gov/modelforce/trop.aer/ .
85229. chris1204 at 22:22 PM on 23 May 2011
       Skeptical Science Educates My Students
       Alas, dear les, I never expected my humble offerings to get so much attention.
85230. Charlie A at 22:22 PM on 23 May 2011
       Roy Spencer’s Latest Silver Bullet
       I gave a reference to the homepage of Isaac Held's blog and mentioned blogposts 3 through 6 as being the relevant ones. I see there is a need to be more specific. Blogpost #3. The simplicity of the forced climate response shows how the globally averaged results of the CM2.1 model can be emulated with reasonable precision with a very simple 2 term model with 4 year time constant. The parameters for this emulation include a sensitivity of 3.5 W/(m2 K0, which is the equivalent of about 1.5 C increase for a doubling of CO2. Willis Eschenbach has detailed a similar calculation for both GISS E and the CCSM3 models. See Zero Point Three Times Forcings and Life is like a Black Box of Chocolates For more details and a replication of the same toy model of GISS E in R, see Climate audit post Willis on GISS Model E". ------------------- If you prefer to see what Hansen says about this, then look at figures 7 and 8 of his recent self published white paper, "Earth's Energy Imbalance and Implications". Here's a copy of Figure 8A, showing the response function of GISS E for the first 123 years. Fig 7 shows the longer term response, with about 80% response at 600 years and almost to equilibrium after 2000 years. So if the GISS E equilibrium response is 3.0C for a doubling of CO2, the GISS E models predicts only a 1.2C rise 8-10 years after a doubling of CO2; about 1.5C rise at 50 years after a doubling of CO2, rising to 2.4C after 600 years and then 3C after 2000 years.
85231. JMurphy at 22:12 PM on 23 May 2011
       Coral atolls and rising sea levels: That sinking feeling
       Arkadiusz Semczyszak, when I saw that your first 3 links were from WUWT and CO2SCIENCE (i.e. non-scientific), I didn't read any further. You really do need to ask yourself why you rely so much (especially in that last post of yours) on second-hand information filtered through blogs.
85232. les at 22:07 PM on 23 May 2011
       Skeptical Science Educates My Students
       81 - Chris. It's a little difficult. the SkS site isn't a bulliten board or such. There's no 'like' button and chat / off topic meanderings is largely not appreciated... so people may not reply or respond to all your posts. Could be the best place for your contributions re: Aristotle, physics etc. would be FaceBook?
85233. Marcus at 22:06 PM on 23 May 2011
       Carter Confusion #1: Anthropogenic Warming
       I'm also curious-how did these people, supposedly with backgrounds in physics, miss something as basic as the ability of Carbon Dioxide to absorb infrared radiation. I'm no expert in physics, but even *I* know about this basic property of the Greenhouse Gases. They also don't seem to understand that evapo-transpiration is good at explaining heat transfers over very short time frames, but really isn't a very good model for explaining the long term build up of heat in the atmosphere & our oceans. Maybe a remedial education is in order?
85234. Arkadiusz Semczyszak at 22:05 PM on 23 May 2011
       Coral atolls and rising sea levels: That sinking feeling
       So look past changes in “coral” sea level (eg. Maldives) compared with the current. Ocean acidification and coral bleaching ... In area of the tropical reefs just changed acidification ( here and here) ... when coral bleaching we must remember the conclusions of this work: Suggett & Smith, 2010. - notes contained therein - the recommendations: “While this synonymous association has undoubtedly been key in raising public support, it carries unfair representation: nonlethal bleaching is, and always has been, a phenomenon that effectively occurs regularly in nature as corals acclimatize to regular periodic changes in growth environment (days, seasons etc).” “While bleaching induced coral mortality must remain our key concern it must be better placed within the context of bleaching signs that do not result in a long-term loss of reef viability.”
85235. Marcus at 22:02 PM on 23 May 2011
       Carter Confusion #1: Anthropogenic Warming
       @ Tom Curtis: Hasn't that always been the Denialist meme? The idea that 97% of the world's climate scientists don't *really* understand how the climate works-only a handful of "truth-seekers"-like Nicol, Kinninmonth, McLean & Plimer really understand what's going on. Or at least that's what they want the media & policy-makers to believe. I've seen Kinninmonth's "hypothesis" before, & they sound just as bogus when Nicol lays it out as it did when Kinninmonth originally proposed the idea. Of course the hypothesis doesn't work, because it then doesn't explain how the planet has managed to warm by around +0.5 degrees C over the last 30 years. After all, what happens to that heat once it reaches the atmosphere? Tropospheric Warming & Stratospheric Cooling would suggest that its not getting beyond the troposphere, which is pretty much as high as evaporative processes actually work anyway. After all, what goes up, must come back down again.
85236. les at 21:55 PM on 23 May 2011
       Carter Confusion #1: Anthropogenic Warming
       33 jonicol - Thanks for that! It's very encouraging to know that you need no more than 2nd year physics to understand climate science.
85237. Marcus at 21:55 PM on 23 May 2011
       Carter Confusion #1: Anthropogenic Warming
       Just a few points John Nicol. #1: Being a meteorologist-no matter how distinguished-is not the same thing as being a climate science. This is a distinction which still appears to be utterly lost on the members of the Denial-o-sphere. #2: Weather is chaotic & hard to predict; long-term climate is relatively stable & easy to predict *if* you know what the long-term inputs & feedbacks are-because all the chaos of individual weather events tend to cancel out over periods of years to decades to centuries. Heck, if *weather* were so unpredictable over the longer-term, then we'd have no such thing as *Seasons*-but seasons represent one form of long-term stability that climate represents. #3: Whatever William Kinninmonth's past calling, his current close ties with organizations like the Lavoisier Group & now ACSC-both organizations fully funded by the Fossil Fuel Industry-makes any statements made by him highly suspect & incredibly biased. Same is true of Plimer & McLean, both of whom have shown a willingness to misrepresent the data to advance the denialist agenda. You see, John, your little song & dance might get you loads of attention from your mates at The Australian, but here we hold contributors to a much higher standard of evidence-& evidence is something which Carter, Kinninmonth, Plimer & McLean have never had.
85238. chris1204 at 21:53 PM on 23 May 2011
       Skeptical Science Educates My Students
       Shucks, les, and here I was taking you seriously all this time. Win some, lose some.
85239. Tom Curtis at 21:43 PM on 23 May 2011
       Carter Confusion #1: Anthropogenic Warming
       jonicol @33, so I am to understand that the new denier position du jour is that the climate is much to complex to be fully understood ... except by Kinnimonth who understands everything.
85240. Marcus at 21:42 PM on 23 May 2011
       Humlum is at it again
       Jarch-The Theory of Evolution is full of holes-with breaks in the evolutionary record & an inability to properly quantify the *rate* of evolution in various species. Yet we still accept the theory of evolution because its backed by the fossil record & by our knowledge of how genetics, anatomy & a host of other biological processes work. Compared to Evolution, the Theory of Anthropogenic Global Warming is much more robust & more easily quantifiable. So I see once again, Jarch, that your claims are completely without any substance. Indeed, they're utterly nonsensical & display a complete lack of knowledge of how science actually works.
85241. Arkadiusz Semczyszak at 21:39 PM on 23 May 2011
       Corals are resilient to bleaching
       And what happened with this paper? Interpreting the sign of coral bleaching as friend vs. foe, Suggett & Smith, 2010.: “While this synonymous association has undoubtedly been key in raising public support, it carries unfair representation: nonlethal bleaching is, and always has been, a phenomenon that effectively occurs regularly in nature as corals acclimatize to regular periodic changes in growth environment (days, seasons etc).” “Observations of non and sublethal bleaching (and subsequent recovery) are arguably not as readily reported as those of lethal bleaching since (1) the convenient tools used to quantify bleaching yield major ambiguity (and hence high potential for misidentification) as to the severity of bleaching; and (2) lethal bleaching events inevitably receive higher profile (media) attention and so are more readily reported.” “While bleaching induced coral mortality must remain our key concern it must be better placed within the context of bleaching signs that do not result in a long-term loss of reef viability. [...]”
85242. Bob Lacatena at 21:36 PM on 23 May 2011
       Skeptical Science Educates My Students
       apiratelooksat50,

       The various science departments at that school are heavily slanted towards support of the AGW theory. However, the faculty at the state university of about 30,000 students generally leans toward support of natural causes of GW.

       And what does this tell you? The people who are qualified to make the call (i.e. that understand and respect the science) are "heavily slanted" towards accepting AGW. The rest don't want to believe, and don't have the foundation in the sciences which would force them to accept the truth, so they rather casually refute it. I say "casually" because I know that if they understood it, or even talked to the science department, they would not hold the position on the issue that claim. I think it's your job to teach science, not your own interpretation of the science. So far, actual climate scientists (that whole 97 of 100 thing) say "AGW," and the science departments at your nearby university say "AGW. The English and history and art teachers all say "natural," and the uneducated student body says "natural," and you say "natural", and then you present that as a "balanced" position to your own students (and probably with more than a little "hint" in your voice, because you agree with the English teachers and the uneducated college students). Where are you failing in this picture? No one who understands the sciences has doubts about this. If you honestly have doubts, then you don't understand the science. If you are a science teacher, that's unacceptable. Comment less and study more, pirate.
85243. jonicol at 21:34 PM on 23 May 2011
       Carter Confusion #1: Anthropogenic Warming
       Marcus, I just thought I should let you know that Bill Kininmonth happens to be one of Australia's most distinguished meteorologists. To help you understand what that means, he has studied the atmosphere, its changes and the physical processes which influence its behaviour in great detail. He is first a physics graduate, with an understanding of a great deal of the necessary mathematics and thermodynamics as well as advanced Newtonian mechanics involving Lagrange's equations, Euler's equations in various appropriate co-ordinate systems whether Cartesian, Spherical or Cylindrical. He understands the connditions in the atmosphere where it is appropriate to describe the mechanics in terms of Lagrange's equations and where it is necessary to apply an Eulerian approach. He understands the differential equations of fluid dynamics and the interaction between the ocean and wind together with the effects on the atmosphere of evaporation and condensation. He understands the mechanism in its totlaity involved in warming the atmosphere by evaporation from the oceans and water bodies, as well as the cooling effect this has on the water. He understands the cooling of the land surface by wind associated also with the ewarming oif the air followed by upwards convection. Over the past many years since his retirement he has continued to apply this knowledge in analysing climatic situations which after all are largely, though of course not totally, an extension of meteorology. My question to you is: Do you understand all of these things?
85244. les at 20:40 PM on 23 May 2011
       Skeptical Science Educates My Students
       78 Chris: I did appreciated the humor of 70 and, even more so, your other weird takes on the history of physics and philosophy... but 'repeating' a witticism (76) seems to indicate that it is you who are taking your ideas seriously! But, yes, the appropriate audience may, indeed, be amongst the more easily impressed.
85245. dhogaza at 20:34 PM on 23 May 2011
       Humlum is at it again
       Nitpick on "AGW theory". There really is no such thing. We have: 1. a theory of how changing concentrations of GHG and associated feedbacks affect climate. 2. an *observation* (not hypothesis or theory) that humans are dumping large quantities of CO2 into the atmosphere, and various projections of what that means for the future derived from applying #1. "AGW theory" is typically used by the denialsphere to emphasize the "A" part, which many want to believe is politically driven, from the physical underlying theory, for which no conspiracy theory fits. Let's not help them out. It's a small thing, but it annoys me.
85246. chris1204 at 20:30 PM on 23 May 2011
       Skeptical Science Educates My Students
       Dear les and scaddenp The world comprises two groups of people - those who appreciate my sense of humour and those who don't. Admittedly, there might just happen to be other ways of classifying people but let's not go there :-) Oh well, I'll have to pick my audience more carefully next time.
85247. Kevin C at 20:10 PM on 23 May 2011
       Roy Spencer’s Latest Silver Bullet
       Great post! I was particularly interested in the following paragraph:

       In a recent blog post, climatologist Isaac Held examined just this issue. He actually took a model exactly like Spencer’s and fit it to the output from a GCM that he uses. Then he estimated the equilibrium climate sensitivity of both models by running them with a constant forcing equivalent to doubling the CO2 in the atmosphere, and finding the temperature they settled into after a while. It turned out that whereas the GCM had a sensitivity of about 3.4 °C (2x CO2), the simple model only had a sensitivity of about 1.5 °C. This is interesting, because the simple model was parameterized specifically to mimic the output of the GCM. Could it be that the issue of overall climate sensitivity is more complex than a model like Eqn. 1 can address, at least over timescales of a few decades? Could it be that such a model would consistently low-ball its estimated climate sensitivity? One thing is clear–Roy Spencer hasn’t asked questions like these, whereas bona fide climate modelers like Isaac Held have.

       I've been reading back over some of Authur Smith's old posts on two-box and other models, and had just come to this one (link) on calculating the response function directly by what is essentially a parameterised deconvolution. He also gets a low sensistivity: about 1.7C/2x over 50 years, although this increases to 2.7C if you integrate the long tail beyond 50 years. Tamino's 2-box model gives 2.4C, but he is also integrating a long tail. Integrating over a long tail seems suspect when you are deconvoluting a 130 year time series which shows probably only 40 years of unambiguous CO2 forcing, so from both of these I draw the same conclusion as you: simple models give low values of sensitivity compared to GCMs. (I'll try my own deconvolution when I get time). The question 'why?' is certainly the interesting one. Could the long tail issue be the key? e.g. suppose GCMs include a significant contribution from a heat resevoir (presumably the deep ocean) with a characteristic time in the high-decades to centuries? And that the simple models can't reproduce this because of the short period over which CO2 forcing has been dominant? I guess that's a question which could be answered by simulation. Or alternatively by using paleoclimate data in deriving the parameterisation of the simple model. Kevin p.s. Possible sources for Spencer's 2003-2010 data: he may have reconstructed the forcings himself from the raw data, but NASA also provide predictions for the future forcings here: http://data.giss.nasa.gov/modelforce/ - go to the 'Future scenarios' section just above the citations. I would have started here and updated the CO2 and solar data.
85248. les at 19:57 PM on 23 May 2011
       Skeptical Science Educates My Students
       76 - Chris: Totally off topic, but that is a cheep bit of philosopause you're doing there. Quintessence is not re-cycling of an ancient concept, but an ancient name - indeed, in a tongue-in-cheek way. Nor (re 70) is Quintessence identical with Dark Energy - it's a mathematical formulation of a kind of scalar field which may be a candidate for modeling dark energy. I wouldn't bother mentioning it; but this is exactly the kind of woolly reasoning that crops up in "skeptical" arguments - like "well, the sun produces heat so much be responsible for GW", in which folks don't appreciate the details and the degree to which these things are quantifiable can calculable.
85249. chris1204 at 18:48 PM on 23 May 2011
       Skeptical Science Educates My Students
       Sorry, I can't get the link to work. However, if you trawl through the Wikipedia entries on Quintessence and Dark Matter, you'll find references to the ether of early classical physics (not the same thing but nevertheless we see some evidence of recycling of an ancient concept). After all, leeches are now all the rage in some fields of medicine today (but of course, they're bred in aseptic settings).
85250. scaddenp at 18:47 PM on 23 May 2011
       Skeptical Science Educates My Students
       "However, the faculty at the state university of about 30,000 students generally leans toward support of natural causes of GW." The science faculty? The basis for such a statement would be very interesting. Frankly, I would expect science departments of all varieties to support the view of published science. If it doesn't, then sounds like your country is utterly stuffed. The typical "skeptic" scientist is someone from outside climate science who has "gone emeritus". This isnt too unusual - look at Pauli and Hoyle - but finding an instance of such folk being actually right is whole lot tougher. Examples anyone?

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