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Comments 75151 to 75200:

  1. CERN - Saying Nothing About Cosmic Ray Effects on Climate
    Chris, There is a large body of evidence regarding climate sensitivity. Unfortunately, the more evidence accumulated, the greater the range has become. This is likely due to changes in recent models that were not incorporated into earlier versions, while averaging over the entire dataset. While the observed warming during the 20th century may have resulted in a calculated climate sensitivity close to 2, using data from 1880 - present, yields a climate sensitivity of ~1.75 per doubling of CO2. This assumes that the observed temperature increase was solely due to the increased atmospheric CO2 concentration. Incorporating any other direct forcings such as solar, aerosols, or volcanic activity, and indirect forcings such as ENSO events, clouds, urbanization, etc. would not only change that value, but add additional uncertainty. I know some people do not like to talk about the uncertainty because it raises doubts among the general populace, and others like to play up the uncertatinty for the same reason. However, refusing to admit this only fools ourselves. IMO, the 2-4.5 range is rather optimistic as it assumes low forcings for many of the attributes mentioned in this thread, and low tropical convectional heat transfer. This may just be my bias (or age) showing, but I have always maintained that direct observations and measurements are more reliable than modelling.
  2. CERN - Saying Nothing About Cosmic Ray Effects on Climate
    jpat (@ 47) re: "...although I note your assumption that the solar cycle and GCR are exact equivalents, the validity of which I am unsure." Of course I didn't say they are "exact equivalents", but that the solar irradiance and GCR flux have essentially the same (antiphase) relationship with respect to the solar cycle. You can see this here, for example. and I don't understand this: "...you seem to have an ability to distinguish cause from effect that my 35 years have not afforded me." Which cause/effect relationship are you thinking of specifically? Are you suggesting that the very marked warming of the last 40 years is the cause of the massive enhancement of atmospheric greenhouse gas concentrations?That makes zero sense. Or that changes in tropospheric temperature are the cause of the solar cycle? (only joking!) It would help if you could clarify. "Really? My understanding is that there is great uncertainty about the feedback mechanism by which CO2 exerts its effect on global temperatures, both in process and magnitude." Yes there is uncertainty about the magnitude of the equilibrium response to greenhouse gas forcing. A large body of evidence supports an equilibrium response near 3 oC at equilibrium per doubling of [CO2], but this might be as low as 2 oC and as high as 4.5 oC taking an estimate of 95% certainty into account (the high-climate-sensivity side of the earth respone to greenhouse forcing isn't well constrained). Even simple consideration of 20th century warming indicates that 2 oC per doubling is likely to be an absolute lower limit since we've already had the amount of warming equivalent to a climate sensitivity of 2oC without factoring in the warming still to be accrued due to already emitted grenhouse gases, and the large negative aerosol forcing that counters the effect of enhanced greenhouse forcing. But it's correct to say that the warming we've seen is consistent with expectations, without proving that any specified values of climate sensitivity and response time constants are correct. as for: "Really? The authors of the paper you referenced say "Contrary to recent assessments based on theoretical..." That's good, you've read the paper and you highlight an important point. The examples I gave about concordence of greenhouse-responsive attributes (stratsophereic/tropopause/diurnal temp range effects etc) aren't from models as such but arise from broadly straighforward principles that underlie our understanding of the greenhouse effect. Looking specifically at the Lean/Rind discussion that you highlight indicates that of course the Global Circulation Models (GCM's) are not completely correct. We wouldn't expect them to be, and in fact should be a little suspicious if they purported to be so! So global scale warming is occurring broadly as our basic understanding (and models) predict as described by Lean/Rind (and many other analyses). However detailed descriptions of the latitude-specific responses and so on seem not to be fully captured in models. That highlights the utility of models, since they increase confidence that we've got the broad (higher-level) aspects of the climate system about right, and also show us the (sub-levels) where efforts at imporved understanding might be focussed.
  3. Republican Presidential Candidates vs. Climate Science
    In a welcome bit of irony, a new poll finds that the hard anti-science stance amongst most of the GOP presidential candidates may actually be generating increased belief in AGW amongst Americans. Basically, when the crazy guy who thinks the best way to deal with his entire state being on fire is to pray for rain says that 'anthropogenic global warming is a complete fraud'... people start to wonder if maybe they need to take another look at the facts.
  4. Climate's changed before
    Thanks.
  5. Water vapor is the most powerful greenhouse gas
    PCB, yes I noted that water vapor concentrations vary significantly... but the fact that it can get up to 95% of total greenhouse warming, total greenhouse gas molecules, relative humidity, or other factors does not explain what 95% factor Ken was referring to as a constant. As to your claims about water vapor variations not being considered in climate models... they just aren't true. At that, the very term 'CO2 models' suggests a fictional belief system... climate models account for a large number of forcings and feedbacks, not just CO2.
  6. One-Sided 'Skepticism'
    I am surprised that no one has pointed out that it actually has warmed from 2003 to 2011, so Pielke is mistaken about 'cooling'. There are plenty of facts out there; it is better to avoid working oneself up in a froth but to keep pointing out the errors.
  7. One-Sided 'Skepticism'
    As the ad hominem argument comes back again and again and anyhow in the denialist discourse, I think it's time to introduce the concept of ad hominem fallacy fallacy.
  8. Arctic sea ice low – what does it really mean?
    villabolo, no I can't offer any papers or other objective evidence. Personal opinion? OK. My view would be that the major influence over this period is the steadily warming ocean waters. Regardless of the season, there is always liquid water beneath all but the tightest of landfast ice. And that water is now warmer, year in, year out, than the same inflows and currents were 15 and more years ago. (Warm being a relative term. I'm not starting swimming classes.) That warmth constantly weakens even if it doesn't actually melt ice. It also means that much less insolation and shorter time periods are needed to get the melt season going. Even if we get our act together to cut ghg emissions, we'll have to see several years, if not decades, of less and less ice because of that ocean heat being unable to dissipate before various currents carry it to the ice.
  9. One-Sided 'Skepticism'
    The interpretation here is that his "Pielke Piles It On" posts wanted to start with a pitch in the dirt about ad homenim's: in this case, the titles used on SKS. He used the standard ploy of deflection when his own words mocked his claimed affront at the content. The real intent of his original post was support for the two UAH custodians. The content of his post is a revisionist apology for the seemingly never-ending fixes required to the complex MSU datasets. The lead-in rub at Blog-x (SKS was convenient) was to create underdog sympathy for Christy and Spencer. In that sense it worked. After reading his defence, I feel even sorrier for those two than I did before.
  10. One-Sided 'Skepticism'
    Wow! I just read Pielke's so-called rebutal. "Hasn't since 2003". What ever happened to noisy data, and long trend lines and statistical signficance? What is that man thinking? And since he does seem to believe in global heat accumulation where does he think the heat is going? Is it just staying in the oceans? What?
  11. Arctic sea ice low – what does it really mean?
    Silly question of the week. Does anyone have a rough idea how much the ice would have been effected if Solar insolation had not dropped since 2002?
  12. One-Sided 'Skepticism'
    NewYorkJ, Not to sound like a concern troll, but I think you would have helped me with the specifics on why Spencer's 1997 work was so wrong. And given Pielke no wiggle room.
  13. One-Sided 'Skepticism'
    Dr. Pielke, Since comments aren't allowed on your blog, I'll address this question here. You say "The ad hominem presentations on this subject include those from the weblog Skeptical Science" with the subject being the robustness of the UAH MSU temperature data. In your response, you do point out an article entitled "Satellite measurements of warming in the troposphere". I looked over this article and could not find any ad hominens. In fact, I see a very good analysis of the claim being addressed, which was Bob Carter's fairly recent statement "Satellite measurements indicate an absence of significant global warming since 1979, the very period that human carbon dioxide emissions have been increasing rapidly." The article ends with the statement "Science advances by trial and error. The result is an increased knowledge of how to measure the temperature of the troposphere from space." which I would hope you can agree with. So please identify the ad hominens in that article on any others dealing with the UAH record. If you find no ad homs, perhaps you could highlight and discuss what specifically you feel is inaccurate. Next, is there anything about Spencer or his work you are willing to criticize? SkepticalScience has been remarkably reserved at staying away from anything personal, given Roy Spencer series of statements overstating his case, past and present. Recall that in 1997, he wrote: "So the programs which model global warming in a computer say the temperature of the Earth's lower atmosphere should be going up markedly, but actual measurements of the temperature of the lower atmosphere reveal no such pronounced activity. In theory, one could argue that the computer models are accurate, and that the real measurements have some problem. However this is not the case. An incredible amount of work has been done to make sure that the satellite data are the best quality possible. Recent claims to the contrary by Hurrell and Trenberth have been shown to be false for a number of reasons, and are laid to rest in the September 25th edition of Nature (page 342). The temperature measurements from space are verified by two direct and independent methods. The first involves actual in-situ measurements of the lower atmosphere made by balloon-borne observations around the world. The second uses intercalibration and comparison among identical experiments on different orbiting platforms. The result is that the satellite temperature measurements are accurate to within three one-hundredths of a degree Centigrade (0.03 C) when compared to ground-launched balloons taking measurements of the same region of the atmosphere at the same time." Accurate Thermometers in Space Given the history and magnitude of the errors, I find it strange that there are many who will swear by the satellite record, all the while depicting the surface record as fraudulent, and those who manage it as frauds. Lastly, I don't see anything fundamentally wrong with what Trenberth, Abraham, and Gleick wrote, other than perhaps their use of the word "forced" in reference to the major errors. I suppose "forced" isn't technically true, in that they could have ignored the errors that had become obvious, but such a course of action would have been unlikely. The authors could have done without that word. Could you point out specifically what you feel is inaccurate and what needs to be retracted? Thanks for your time. I'm glad you've stopped by here on occasion and hope you will stick around to read beyond the headlines, and maybe make some constructive contributions here.
  14. One-Sided 'Skepticism'
    Chris@1204, Come on, please don't try and play it is only "satire" card; this is about science and truth. I am willing to bet you that his target audience would not have seen it that way-- many of his readers at his blog do not believe in the so-called "greenhouse" effect. So they are pretty gullible for the most part and he is preying on that. And you forget, there is in fact a myth out there on the internet that we humans are contributing to the rise of CO2 by exhaling, and Spencer is feeding that myth in a public forum. Do you deny the existence of the myth? Spencer knows better, it is inexcusable. And it is along the lines of Christy twice failing to set the senator straight who fed him the "1970s global cooling scare" myth when he testified before the US Congress recently.
  15. CERN - Saying Nothing About Cosmic Ray Effects on Climate
    47, jpat,
    I am just trying to separate out what we know from observation vs what we think we know from simulation.
    Then start reading. This site is full of information. Start anywhere. Search for anything. Read. Learn. The WUWT [-snip-] mantra that "the models" are the end all and be all, and the weapons of evil and falsehood, is quite simply as I described it... [-snip-] Read and learn, and drop the lame, uninformed comments like "one of the knobs the modelers twirl" (wrong) and "what we think we know from simulation" (gross exaggeration and misdirection).
  16. CERN - Saying Nothing About Cosmic Ray Effects on Climate
    jpat - "We're interested in what causes the trend.", as if the variability in a non-linear dynamic system is incapable in and of itself as causing a trend. I can tell you without fear of contradiction that that is decidedly not the case." You need to look at the boundary conditions, namely conservation of energy - the centerpoints around which chaotic systems (i.e., non-linear systems) must orbit in their strange attractors. See the Chaos theory and global warming: can climate be predicted thread for a discussion of this. Non-linear interactions and state-space changes cannot modify energy levels ab inito - they can cause chaotic variations around energy equivalences, but not create/destroy energy. Non-linear interactions cannot cause an unlimited trend, as any study of strange attractors will tell you.
  17. Climate's changed before
    Mankind's influence aside, should we otherwise be in a cooling phase of a Milankovitch cycle at present, in other words, on a downward slope, chart-wise?
    Response:

    [DB] In the absence of anthropogenic forcings, yes.  Since the Holocene Climatic Optimum some 6,000+ years ago the net forcings (without man) have been negative and the overall temperature trend downward.

    The long, slow slide back to glacial conditions had already begun.  Now evidence shows we have little to worry about (the next cold phase of the ice age cycle).

  18. One-Sided 'Skepticism'
    As another example, do you agree with Roy Spencer when he said that as a result of addressing climate change, "Jogging will be outlawed. It is a little known fact that the extra carbon dioxide (and methane, an especially potent greenhouse gas) emitted by joggers accounts for close to 10% of the current Global Warming problem"? You mean you didn't notice the satirical context? Hello?!?!
  19. One-Sided 'Skepticism'
    When Skeptical Science and Real Climate use science to critique papers and comments by Spencer, Lindzen, Christie etc, I have never seen a rebutal based on science. Just like Dr. Pielke in this instance, it is inuendo, personal attacks, and change the subject. One can only conclude that their objectives are not scientific, but rather propaganda.
  20. CERN - Saying Nothing About Cosmic Ray Effects on Climate
    Also, note the response to Lean and Rind's analysis on trends by Stott and Jones 2009.
  21. One-Sided 'Skepticism'
    Key statement at Pielke's: Comments Off. On the other hand, the "Insightful interview" he relates, http://pielkeclimatesci.wordpress.com/2011/09/02/insightful-interview-in-eos-of-dr-de-zheng-sun-climate-dynamics-why-does-climate-vary/ insightfully suggests that things may be worse than we thought.
  22. Climate Communication: Making Science Heard and Understood
    pirate#30: "writing using an economy of words in a way that is easily understandable." That description applies equally well to lab and research reports, which are richer in content. "Writing the survey in the best attempt to remain neutral ... is not an easy task" agreed. So I would think you would want your students to have already learned something about the subject before attempting this difficult task. Unless your school year is vastly different, it's pretty early to have finished the subject of climate change. What information are your students using as the basis for their questions?
  23. CERN - Saying Nothing About Cosmic Ray Effects on Climate
    'if the variability in a non-linear dynamic system is incapable in and of itself as causing a trend." - however, this is not the case for any physical model of climate. You might like to see here "Isn't in fact this sensitivity one of the knobs the modelers twirl?" No, sensitivity is an output not an input. It is bound into the model by way of the equations that describe interactions within the climate system. These are either straight physics or parameterisations from emperical data. With no feedback, it obviously still warms the climate - just slower. For increasing CO2 NOT to warm the planet, then there must exist a negative feedback stronger than the sum of the positive feedbacks. There is no evidence for such a system.
  24. One-Sided 'Skepticism'
    The big time deniers, needing to explain to themselves why scientists do not agree with them, conclude that it is all politics (projection) and this absurdity forces them into endless additional absurdities. Note by the way that "It's all politics" is absurd to start with. There is a real planet earth with a real climate. Hence there really is a right answer. It can not be all politics.
  25. One-Sided 'Skepticism'
    On the subject of delayed warming, remember our cooling layer of acid sky (sulfate areosols) which goes away when we try to stop warming. Just a little good by kiss.
  26. One-Sided 'Skepticism'
    Bern, there is a referee. Reality. But, we have to wait a lot longer than we usually do for the 'third' referee in the box to announce the result of a disputed call.
  27. Arctic sea ice low – what does it really mean?
    More heat for CBD: August was a warm month in the Arctic...and the Antarctic as well: [Source] Looks like da Summertime at bot' da poles, eh?
  28. CERN - Saying Nothing About Cosmic Ray Effects on Climate
    Chris, you seem to have an ability to distinguish cause from effect that my 35 years have not afforded me. Re 44, we are in general agreement in paragraphs 1 and 2 although I note your assumption that the solar cycle and GCR are exact equivalents, the validity of which I am unsure. Then you state, "But as far as global warming we're not interested in the contributors to variability around the secular trend. We're interested in what causes the trend.", as if the variability in a non-linear dynamic system is incapable in and of itself as causing a trend. I can tell you without fear of contradiction that that is decidedly not the case. >Working the other way, we know that all else being equal, increased [CO2] must cause warming and we have a reasonble handle on how much. Really? My understanding is that there is great uncertainty about the feedback mechanism by which CO2 exerts its effect on global temperatures, both in process and magnitude. Isn't in fact this sensitivity one of the knobs the modelers twirl? >Our confidence that this is the case is further establshed by observations that greenhouse-specific correlates of warming (stratospheric cooling, raised height of tropopause, specific effects on diurnal temperature range and so on) are observed as expected. Really? The authors of the paper you referenced say "Contrary to recent assessments based on theoretical models [IPCC, 2007] the anthropogenic warming estimated directly from the historical observations is more pronounced between 45S and 50N than at higher latitudes (Figure 3d(right)). This is the approximate inverse of the model simulated anthropogenic plus natural temperature trends in IPCC (Figure 9.6)...Climate models may therefore lack – or incorrectly parameterize -fundamental processes by which surface temperatures respond to radiative forcings." As someone with a lot of experience with these kinds of models, I am suspicious of their usefulness in attribution. That does not mean I am skeptical of AWG, I am just trying to separate out what we know from observation vs what we think we know from simulation.
  29. apiratelooksat50 at 11:04 AM on 16 September 2011
    Climate Communication: Making Science Heard and Understood
    Sphaerica at 30 We do need to continue our dialogue. I am now back from Wisconsin and swim season is winding down. My request for some of the posters here to design the survey is genuine.
  30. apiratelooksat50 at 11:03 AM on 16 September 2011
    Climate Communication: Making Science Heard and Understood
    muoncounter@28 Our school is an early college academy where students can get dual credits in high school and college level courses. We are also an Exemplary Writing School and focus on writing. The educational benefit to writing a survey is valid. In ANY class writing and reading are paramount. 1. It is writing using an economy of words in a way that is easily understandable. 2. Writing the survey in the best attempt to remain neutral and not present a bias is not an easy task for anyone (see #11).
  31. CERN - Saying Nothing About Cosmic Ray Effects on Climate
    jpat#40: "a bit convenient for those trying to disprove the GCR hypothesis." One hardly needs 'convenience.' GCRs have a long way to go before rising to the level of hypothesis. Refer to the 4 unproven requirements in this posting; then ponder Esop's dent-making point, as well as the stunning lack of results in the paper discussed here.
  32. One-Sided 'Skepticism'
    My mistake, I was just thinking about surface warming and not taking the global energy imbalance into account.
  33. CERN - Saying Nothing About Cosmic Ray Effects on Climate
    "...the justifications for the adjustments to PMOD data seem implausible and the effects of those adjustments over the time period in dispute a bit convenient for those trying to disprove the GCR hypothesis."
    I'd say the opposite! First, the question of whether ACRIM, PMOD or IRMB composite is used has essentially no effect on conclusions re CRF contributions. The CRF has simply not trended significantly in the direction required for it to have contributed to the secular warming trend. In fact the year 2010 is the warmest year on record in the NASA Giss compliation occurring at a time when the CRF is the highest it's been since direct measures began. Since the CRF is proposed to affect climate through cloud nucleation which is an effectively instaneous response (max cloud response a few days after change in CRF according to Forbush event analysis), it's very difficult to consider a significant role for CRF when the period with the maximum cooling contribution coincides with the maximum warming on record. For those that wish to assert that solar irradiance has undergone a tiny rise, rather than a modest fall during the last 25 years, the use of the ACRIM composite would actually be the "oh-so-convenient" observation! But it's a little hard to swallow that the solar outputs wax and wane in a rather regular fashion, but suddenly undergo a jump of a few tenths of a W.m-2, just during the few months when the satellite observations were lost! In fact the Lockwood paper I linked to above discusses this in detail and you should read it. The bottom line is that the Acrim composite is (among other problems) simply incompatible with independent (ground based) observations that span the "gap". But the Lockwood 2010 paper gives lots of insight on this...
  34. One-Sided 'Skepticism'
    KR, when SkS discusses the 'delayed warming', we are quite clearly discussing not only what Dana mentioned, but also the warming due to already emitted CO2. So Pielke isn't actually arguing against our argument. He's arguing about thermal lag. That quote he used came from a post that spelled out the reasoning about risk, BAU emissions, and all the rest. He's yet to acknowledge anything in that post besides a sub-title. We should all be skeptical.
  35. One-Sided 'Skepticism'
    Is it just me, or does this strike anyone else as the opening salvo in an attack on SkS, following the Eureka Prize win that (hopefully) raised SkS' public profile? I wouldn't be at all surprised to see other 'sceptics' start to weigh in on the matter, much as they done previously with Dr Mann and others. Talking about playing the player, not the ball... shame there's no referee in this match.
    Response:

    [DB] "shame there's no referee in this match"

    There is one; that would be me.  ;)

  36. CERN - Saying Nothing About Cosmic Ray Effects on Climate
    jpat (re 42) one of us isn't getting it and I don't think it's me! Something has caused the earth to warm rather dramatically especially since the 1970's. The warming (which can be described as a secular warming trend), is associated with a massive increase in thermal energy in the climate system that can be directly measured in the oceans. On top of that trend there is variability that has cyclical (solar), stochastic (ENSO) and contingent (e.g. volcanoes) contributions. If we take out the non-solar contributions from this set as S-F claim to have down ('though with zero insight into methodology!), we're left with what might just be the solar cycle contribution. That does indeed correlate weakly with the solar cycle. No problem there I think we'd agree (as would Frolich and Lockwood no doubt). But as far as global warming we're not interested in the contributors to variability around the secular trend. We're interested in what causes the trend. S-F is consistent with lots of work that the solar, ENSO and volcanic contributions to the large warming trend are near zero over this period (e.g. see Lean and Rind 2008, I linked to above). They cause variabilty ("noise" on the warming trend, but (as S-F) indicate make little contribution to the trend. Working the other way, we know that all else being equal, increased [CO2] must cause warming and we have a reasonble handle on how much. The warming trend is consistent with this contribution (i.e. enhanced greenhouse forcing). Our confidence that this is the case is further establshed by observations that greenhouse-specific correlates of warming (stratospheric cooling, raised height of tropopause, specific effects on diurnal temperature range and so on) are observed as expected. As S-F says the contribution to the secular warming trend is due to greenhouse gases. Their odd inference that these could be "natural" greenhouse gases makes no sense at all. And since they give us no insight into the origin of their odd thoughts on this we're none the wiser, other than to say that there is zero evidence that "natural" greenhouse gas contributions have been of any significance whatsoever...
  37. One-Sided 'Skepticism'
    dana1981 - "...but that heat will come from the oceans..." I'm going to have to disagree; that heat will go into the oceans, not come from them, until they reach rough thermal equilibrium. Current temperatures (including ocean heat values) measure what is now in the climate system. The 'delayed warming', or as I prefer to describe it the 'unrealized warming', is the warming remaining to fully cancel out forcing imbalances. There is considerable thermal lag as joules of energy accumulate (primarily in the oceans), and imbalances are not redressed immediately. This is true as long as we have a TOA forcing imbalance and thermal lag. This was discussed at some length in Has Earth warmed as much as expected thread.
  38. CERN - Saying Nothing About Cosmic Ray Effects on Climate
    " we know that the cycles involved are too short to explain the observed trends." Though there is an obvious 11 year cycle there are also several cycles of much longer duration which have been found to correlate with cool and hot cycles of the earth. As the planets revolve around the sun their gravity affects the sun in complex, long cycles which can be mathematically analyzed and predicted. Theodor Landscheidt made some amazingly accurate long term projections of el nino cycles based on the dynamics of the sun. Those methods predict decades of global cooling which will be obvious in a few years if correct. Here is a link to an elementary summary written after several long term predictions came true: http://www.john-daly.com/sun-enso/revisit.htm We certainly shouldent ignore this line of study as it will be impossible to ignore if the predictions come true.
  39. CERN - Saying Nothing About Cosmic Ray Effects on Climate
    Chris, You wrote "The data in S-F Fig. 2 is a straightforward confirmation that solar variation can have had little contribution to the secular warming trend that is especially apparent since the 1970's." I do not see how this follows. If we take out known forcings and the trend (which we both agree is in all likelihood a system response) and establish that the residual is well correlated to another hypothesized forcing, than you've accounted for the vast majority of systemic inputs. How then do you justify your statement that the observed trend is "due to the massive enhancement of greenhouse gas concentrations." The reasoning seems circular to me. That attribution is what you have to prove. It can't appear in your presumptions.
  40. Crux of a Core, Part 3... Dr. Ole Humlum
    Thanks Rob. Then there should be more posts relating to his website ;) It is clever, but misleading. To the diagram/chart: Humlum may have adjusted the chart, but his a priori belief is that CO2 has nothing to do with global warming. The chart, adjusted or not, reflects this belief. So my main point was the general one that he is still using the diagram with this particular combination of temperature and CO2 to prove that "The past temperature changes show little (if any) relation to the past atmospheric CO2 content" And "It can, however, from figures [2,] 3 [and 4] be concluded that the temperature increase 1975-2000 is not unique when compared with past records, and that the net effect on temperature by atmospheric CO2 has been small or even absent"(From Humlums site Besides this very doubtful (a priori) conclusion and use of data, if I understand you correctly there are also these issues: 1. He knows of this post, but still uses the lowest estimation in Box et al 2009 (which he refers to as Brox et al 2009) 2. He is still using a local record, your main point of misrepresentation of GISP2 3. Box et.al. 2009 end their data in 2007, but Box has an additional three years of data that Humlum is not using. 4. He is still using a CO2 record that ends in 1777 To me that makes his diagram/chart five times misleading, but I may be wrong.
  41. CERN - Saying Nothing About Cosmic Ray Effects on Climate
    Argh, the last sentence should read "that the sensitivity to various forcing functions are not constant with time or that the operating point would exhibit near step changes in response to small input perturbations."
  42. CERN - Saying Nothing About Cosmic Ray Effects on Climate
    Chris, Sorry, I don't have access to the scientific literature. But from what I have been able to find, the justifications for the adjustments to PMOD data seem implausible and the effects of those adjustments over the time period in dispute a bit convenient for those trying to disprove the GCR hypothesis. It wasn't my suggestion re natural greenhouse gases. The entire 2nd paragraph was a quote from the paper. But in any case, I don't see your point. If it can be established that a forcing function (be it ITS, GFR or a combination of the two) accounts for significantly more of the variance than is currently modeled, one should not expect the model to track reality nor rely on them for attribution studies. Superposition does not apply. You can just assume small input errors will lead to small output errors that will average out. I've spent 35 years in the design and modeling of non-linear, coupled feedback systems. In all but the lowest of order, these systems can be identified by the fact that they do not exhibit equilibrium in the LTE sense of the word. In the presence of noise, such systems can change regimes at the drop of a hat, exhibiting a whole new dynamic where feedback paths previous insignificant suddenly dominate. A quasi-equilibrium may be reached for a time then suddenly and without apparent cause the output trends off in a new direction. This of course makes attribution challenging, to say the least. Now one would expect a priori that a system as complex and non-linear as the climate would exhibit similar characteristics, so it doesn't seem surprising to me in the least that the sensitivity to various forcing functions are not constant with the operating point.
    Response:

    [DB] "Sorry, I don't have access to the scientific literature."

    Chris' link to Lean and Rind 2008 was directly to an openly-available copy.  Lockwood 2010 similarly was/is freely available (via link from Chris' link), here.

  43. Water vapor is the most powerful greenhouse gas
    'and a major defect in the CO2 models is that they assume it is constant" Sorry, perhaps you would like to explain this further (with references). "It is also different in concentration [and behavior with light] at different altitudes in addition to varying between humid and desert areas near the surface." Not exactly news to climate modellers. What is your point here?
  44. One-Sided 'Skepticism'
    KR @25 - I belive Pielke is basically right on this point. The surface will continue to warm until equilibrium is reached, but that heat will come from the oceans. As long as you account for all the heat in the Earth system, you don't have to worry about the thermal lag. Of course if you're going to take that approach, you do have to account for the entire Earth system, including the deep oceans, which Pielke tends to ignore (including in this "response" post). Taking the deep oceans into account invalidates his argument.
  45. CERN - Saying Nothing About Cosmic Ray Effects on Climate
    jpat, re you comment about integrative systems, the only way this would be of sigificance would be if the small rise in solar output from around 1920's to early 1950's was sufficient to drive the tropospheric temperature towards a significantly raised new equilibrium. However, in such a case the rate of temperature response would have been largest at the earliest part of the response (specially for the troposphere which responds quite quickly to forcings). That's incompatible with the empirical temperature data. In any case the solar scientists that address the earth temperature response to solar variation have determined that the early to mid 20th century increase in solar contributions are rather small. For example, this paper by Lean and Rind (2008) (solar scientists like Lockwood and Frolich) is an accessible account and also describes the earth surface response to the solar cycle which S-F "rediscovered"!
  46. One-Sided 'Skepticism'
    "Similarly, weblogs such as Skeptical Science, if they want to move the debate on the climate issues forward, need to move towards a more constructive approach." A comment like this makes Pielke seem like a concern troll. He has very little of substance to say on the things we're saying, but rather is highly critical of how we're saying it. There is, in my opinion, little room for this kind of attitude. If the fake skeptics are lying to the public, we have no obligation to be polite in pointing it out.
  47. One-Sided 'Skepticism'
    Dr. Kerry Emanuel has some sage words in an op-ed: "Science tells us that the extent and severity of climate change faced by our children's generation will be determined by the hard choices we must make today. Political leadership is about ensuring that we adults face up to this task. We cannot afford to have those leading our nation misrepresent, or be silent about, the reality and risks of climate change." That last paragraph also applies to scientists, including Dr. Pielke. While some scientists are turning a blind eye to the risks, others (including SkepticalScience) are being pro active in this regard.
  48. CERN - Saying Nothing About Cosmic Ray Effects on Climate
    jpat, It would help if your criticism of the PMOD composite comes from a reputable source (aka peer-reviewed science). For a very thorough discussion of the ACRIM/PMOD/(IRMB) composites and the justification for using PMOD see Lockwood 2010 Not sure what you're trying to say. The data in S-F Fig. 2 is a straightforward confirmation that solar variation can have had little contribution to the secular warming trend that is especially apparent since the 1970's. That's due to the massive enhancement of greenouse gas concentrations. Can't see your basis for suggesting that might be due to "natural greenhouse gases". That seems very odd indeed! What do you mean by that? If you're saying that the solar cycle variation induces a tropospheric temperature response I doubt anyone would disagree. That's well established, but rather irrelevant both to mid 20th century to contemporary global warming, and to the possible contribution from cosmic rays. It's simply not possible from S-F Fig 2 to seperate the contributions from solar irradiance (which we know categorically has an effect on temperature) and from cosmic rays. They have essentially the same (antiphase) profile with respect to the solar cycle. So S-F confirm that solar contributions (TSI, CRF, open solar flux, sunspot number) has had an insignificant contribution to the recent and contemporary secular (greenhouse gas forced v. likely) temperature trend, and that solar variability through the solar cycle has an effect on tropospheric temperature. Nothing controversial about that at all, and it's certainly not in conflict whatsoever with Lockwood-Frolich. S-F clearly misunderstood the Lockwood-Frolich paper and produced a rather redundant and unpublishable web report.
  49. CERN - Saying Nothing About Cosmic Ray Effects on Climate
    >In other words the cumulative warming has nothing to do with changes in solar outputs which have been broadly trendless (trending in a cooling direction since the mid 1980's) This statement is nonsense. In integrative systems, it is the area under the stimulus curve that counts, not the trend. And in non-linear systems, even symmetrical inputs can give rise to trending outputs.
  50. One-Sided 'Skepticism'
    Well, you can't expect such characters to objectively re-evaluate the actual quality of their work. They are perfectly aware of what the truth actually is, they just have a desperate need to hide from it. Trying to discuss rationally with them as if they can be convinced of anything is futile. The important thing from a scientific standpoint is simply to continue being right, and equally important is to make sure everyone is concretely aware of the exact position of the scientific consensus and where those representing political interests are wrong. Eventually there will come a point where general public hits the tipping point of overwhelming acknowledgement, and the next manipulation from the denialists will be attempts to distort the public's memory of what the science had been saying all along. I imagine there is a degree to which I must be preaching to the choir.

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