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Comments 61551 to 61600:

  1. Rob Painting at 07:17 AM on 24 May 2011
    Coral atolls and rising sea levels: That sinking feeling
    Arkadiusz Semczyszak - See the discussion, references, and particularly Figure 3, provided in the advanced version of this rebuttal. Coral bleaching is likely to have caused the "drowning" of ancient atolls as continental plate motion transported them north through the equatorial "hot zone". And don't confuse natural bleaching with mass coral bleaching.
  2. Carter Confusion #1: Anthropogenic Warming
    I am agasin disappointed that the reponses to my attempts to draw attention for the need to discuss the scientific aspacts of climate change have failed to ignite any passion beyond discussing what climate scientists know and what meteorologists, geologists and physicists know from their background. Sure basic Lagrangian mechanics is the subject of second year physics but Eulerian theory in its fullest form is certainly third year level and well beyond, being the basis in tensor form of Einstein's theory of General relativity. I know this is irrelevant. I am not going to speculate on what climate scientist's background's might be but up until fairly recently climate scientists came across from geography as in the case of Andy Pitman and Matthew England UNSW for instance. That too is irrelevant. However, you must surely recognise that climate science is basically mechanics, fluid dynamics, hydrology, oceanography and, if you include the effects of carbon dioxide, quantm mechanics and high resolution spectroscopy with experience in line broadening and statistical mechanics of gases. Without deep knowpledge in all of these areas, there is not a lot to be done which is useful in the field of climate. As even the climate scientists would agree, climate is a long term assessment of what happens in the weather. The physics which is used to understand this is what is applied to meteorology.
    Response:

    [dana1981] Perhaps you are unfamiliar with our site, but discussing the scientific aspects of climate change is the fundamental purpose of Skeptical Science.

    We've allowed this discussion to get far off topic.  Everyone please keep future comments relevant to the subjects in Carter Confusion #1, or take your comments to the relevant discussion subject.

  3. Carter Confusion #2: Green Jobs
    Ron@6 "Once it becomes more economically feasible to invest in alternative sources of energy there will be a period in which transitioning from old technologies to new technologies..."

    But fossil fuel based technology is 'un-naturally' cheap in historical terms, we are effectively in a very short 'blip' in history where energy has been held at artificially low levels, by exploiting 'solar energy' stored millions of years ago.
    The historical normal 'price' for energy should be a lot higher, the question is whether humanity can see through the artificial state we are in now and start excepting the fact that energy prices should be higher in order to survive.
  4. Roy Spencer’s Latest Silver Bullet
    Albatross, I find do not fully understand Spencer's calculations (assuming that I have found the one that Bickmore refers to ---- it is quite strange that there is no link to Spencer's blogpost). It is also clear from the article that Dr Bickmore does not understand what Spencer has posted. I have not bothered to try and resolved the differences in approaches and understanding between the two gentlemen.

    My main interest in the article was the graph of forcings from Hansen through 2010, along with a link for those forcings. Unfortunately, it turns out that the Dr Bickmore's statement about the provenance of the forcings is erroneous (which he corrected in comment #7, but not in the headpost), and his link only shows the 1880-2003 GISS forcings, with fixed aerosol forcings post 1990.

    A typical problem I have with serious discussion of this article are statements like "One of the problems I pointed out was that his model assumed a 700 m mixed layer in the ocean, when it is really something more like 100 m. In other words, his model assumed that the entire top 700 m of the ocean heats up and cools down at the same rate, which is nonsense."

    A simple review of Spencers calculations shows that, if one is using OHC for the upper 700 meters and the heat capacity for the upper 700 meters, then what one calculates is the average temperature for the upper 700 meters. That Spencer calculates an average temperature for the upper 700 meters is not the same as Bickmore's assertion that "his model assumed that the entire top 700 m of the ocean heats up and cools down at the same rate, which is nonsense." For the sort of analysis that Spencer attempted to make any sense, the layer used for OHC must have essentially zero heat flux crossing the lower boundary, and therefore it is a given that there will be a temperature vs depth variation. Dr. Bickmore's article is written as an attack rather than a discussion or review.

    And I originally noted, a finding of transient sensitivity of 1.3C is not sufficiently novel to motivate me to wade through the mess.
  5. Q and A with Dr Haydn Washington, co-author of Climate Change Denial
    JimJim@23,

    Please also note the Anderegg 2010 paper which found that out of the top 200 climate researchers (out of 1,372, ranked by number of climate publications) 97% agreed with the conclusions of the IPCC.
  6. Bob Lacatena at 06:07 AM on 24 May 2011
    Q and A with Dr Haydn Washington, co-author of Climate Change Denial
    23, JimJim,

    Don't be silly. The questionnaire went out to over 10,000 people. Of those, a little over 3,000 responded. Of those, they belonged to various sciences, so about 150 were climate scientists. Of those, only 79 were actively publishing in the field in the last five years.

    You expect them to have worked with 100,000 questionnaire's? 1,000,000?

    There is nothing whatsoever wrong with a survey of that sort. Especially when the result was an overwhelming 97%.
  7. Q and A with Dr Haydn Washington, co-author of Climate Change Denial
    Talk about cherry picking he is using the 97% number which is based on one study of 77 scientist. Only 77 people and he talks like that is 97%
  8. Roy Spencer’s Latest Silver Bullet
    Charlie,

    Spencer arrived at the curious number of 1.3 C for equilibrium climate sensitivity (he refers to climate sensitivity is the same context as reported in the IPCC) for doubling CO2, because he made several errors as outlined by Dr. Bickmore.

    Spencer has again been shown to be guilty of undertaking a seriously flawed analysis-- do you dispute Dr. Bickmore's debunking of Spencer's error riddled analysis?
  9. Carter Confusion #2: Green Jobs
    It is inevitable that jobs will be lost within the carbon sector only to be offset by job increases in alternative energy technologies.

    The catalyst will be rising costs due to growing demand and shrinking resource within the carbon sector.

    Once it becomes more economically feasible to invest in alternative sources of energy there will be a period in which transitioning from old technologies to new technologies will likely produce a temporary spike in unemployment rates as workers will need to transition as well and will likely entail learning all new skills before re-entering the job market.

    However once this period of transitioning is complete there is potential for substantial growth within the alternative energy sector (not just in construction projects, but trained technicians to maintain the systems) as it scales quite well to suit a multitude of needs (right down to micro, or even nano scale). Needs that could only be met with large scale offerings in a carbon based economy. And substantial growth brings jobs, and wealth, and most of all -- energy security (think outside the obvious).
  10. Bob Lacatena at 04:59 AM on 24 May 2011
    UQ Physics Colloquium this Friday: Communicating Climate Science and Countering Disinformation
    Eric,

    ???

    The study clearly states that the 97% of actively publishing climate scientists comes from:
    ...those who listed climate science as their area of expertise and who also have published more than 50% of their recent peer-reviewed papers on the subject of climate change...
    How is this in any way a problem?

    The CO2 nitpick is similarly silly. Obviously the problem is more nuanced than just CO2, yet the implication that maybe some of those scientists might subscribe to the Pielke "it's land use" or some other variation, and would have ticked off "no" if the question had explicitly stated CO2 emissions, is absurd.

    This train of thought is a real stretch in trying to diminish the authority or reach of the Doran study.

    P.S. Your post has a serious "concern troll" scent to it.
  11. Carter Confusion #2: Green Jobs
    Eric the Red wrote: "That renewable energy has higher labor costs per unit of energy than coal or gas?"

    In the short term renewable energy creates more jobs than coal or gas. This seems self evident given the relative amounts of construction required. That doesn't necessarily translate to higher labor costs as not all workers are paid the same wage. For instance, dangerous coal mining probably pays better than digging post holes for solar panels. I don't think the article above provides enough information to determine overall labor costs.

    It is also noteworthy that renewable energy doesn't have many costs other than labor. That is, you don't have to pay for wind and sunshine like you do coal, oil, and gas. Ergo, comparing only construction costs or even just labor costs could be very misleading.
  12. 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.
  13. 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)

  14. 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.
  15. 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.
  16. 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.
  17. 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.
  18. 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.

  19. 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.

  20. 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.
  21. 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.
  22. 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 ...
  23. 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."
  24. 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.
  25. 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.
  26. 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?
  27. 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?
  28. 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.
  29. 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.
  30. 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.
  31. 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.
  32. 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.
  33. 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.
  34. 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.
  35. 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
  36. 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).
  37. 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.
  38. Skeptical Science Educates My Students
    Don't worry Chris, I'm not typical ... they probably haven't got that much attention overall.
  39. 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/ .
  40. Skeptical Science Educates My Students
    Alas, dear les, I never expected my humble offerings to get so much attention.
  41. 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.
  42. 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.
  43. 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?
  44. 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?
  45. 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.”
  46. 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.
  47. 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.
  48. 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.
  49. Skeptical Science Educates My Students
    Shucks, les, and here I was taking you seriously all this time. Win some, lose some.
  50. 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.

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