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Comments 74451 to 74500:

  1. SkS Responses to Pielke Sr. Questions
    chris - I am glad you brought up Scott Denning's involvement with the Heartland Institute. I know Scott quite well (he and I were colleages at Colorado State University) and I respect his views. Even more importantly, he is willing to engage with the community you call "skeptics". It is also commendable that the Heartland Institute was willing to provide a forum for alternative viewpoints (much as Skeptical Science is doing with my comments although I do not fit in the label of "climate skeptic"). We need more reaching out between the different groups. The Heartland Institute and Skeptical Science have this reaching out in common.
  2. SkS Responses to Pielke Sr. Questions
    Chinahand - you write "Human influences are dominated by our use of fossil fuels causing the emissions into the atmosphere of both greenhouse gases, the most important of which is CO2, and aerosols." The human effects on the enviroment are certail much more than from fossil fuel emissions, so I assume you mean human influences on the climate system. Your way of framing as a hypotheses fits with hypothesis #2b, which has been rejected, in my view (and that of many of my colleagues, as exemplified in the WIREs paper I included in an earlier comment.
  3. SkS Responses to Pielke Sr. Questions
    Dikran Marsupial - for my views on the tropical temperature trends, see Christy, J.R., B. Herman, R. Pielke, Sr., P. Klotzbach, R.T. McNider, J.J. Hnilo, R.W. Spencer, T. Chase and D. Douglass, 2010: What do observational datasets say about modeled tropospheric temperature trends since 1979? Remote Sensing, 2(9), 2148-2169. http://pielkeclimatesci.files.wordpress.com/2010/09/r-358.pdf
  4. SkS Responses to Pielke Sr. Questions
    alan_marshall - You make a fundamental statement which is not supported by the science - You write "The first is correct because the climate is driven by CO2. The major forcings are CO2, methane, etc. and their positive feedback through water vapour, as illustrated diagrammatically on the Sks site." Climate is driven by the spatially and temporally variations in solar heating of the Earth by the Sun. CO2 and the other greenhouse gases represent one major way the climate system responds to this source of energy.
  5. SkS Responses to Pielke Sr. Questions
    Albatross - regarding #42, perhaps this new paper will clarify for you the role of land use/land cover change as a first-order climate forcing Pielke Sr., R.A., A. Pitman, D. Niyogi, R. Mahmood, C. McAlpine, F. Hossain, K. Goldewijk, U. Nair, R. Betts, S. Fall, M. Reichstein, P. Kabat, and N. de Noblet-Ducoudré, 2011: Land use/land cover changes and climate: Modeling analysis and observational evidence. Wiley Interdisciplinary Reviews: Climate Change, Invited paper, accepted. http://pielkeclimatesci.files.wordpress.com/2011/09/r-369.pdf where we write "For those regions that have undergone intensive LULCC, or will undergo intensive change in the future, failure to factor in this forcing has profound consequences. Investments in adapting to ongoing human-induced climate change and natural variability will remain founded on incomplete and potentially misleading information. This in turn leads to a higher risk of misaligned investment in climate adaptation, which is a vastly more expensive outcome than the costs of resolving the impact of LULCC on the Earth’s global and regional climate. Unless we undertake a thorough assessment of the role of LULCC on climate, an incomplete understanding of the role of humans in the climate system will persist."
  6. SkS Responses to Pielke Sr. Questions
    Albatross - You make two errors in your comments. First, a Forum article in EOS is peer reviewed. Second, you write "As someone with numerical modeling experience, I'm confused by Dr. Pielke's (who is a modeler) claim that "Models themselves are hypotheses", in his book "Mesoscale Meteorological Modeling" which is on my bookshelf here, he says on page 1 that "....it is necessary to understand the basic physical and mathematical foundations of the models...". Quite different from what he said in his testimony. He then says "There is no way to test hypotheses with the multi-decadal global climate model forecasts for decades from now as step 2, as a verification of the skill of these forecasts, is not possible until the decades pass." This leads me to conlcude that Dr. Pielke is of the opinion that models are nothing more than untestable hypotheses...it would be a great shame if he thinks that his life's work amounts to that." Models have a basis in fundamental physics (their dynamic core) and also include engineering components (i.e. tunable paramters) as discussed in my book. Their forecasts can be tested, and if the model prediction and the observations are in a large enough disagreement (e.g. determined by skill scores or other tests), the model is rejected as providing skillful forecasts. For forecasts from the climate models, decades from now, we have to wait for those decades to pass. I hope your misunderstandings are corrected. I am pleased that you have my book. :-)
  7. SkS Responses to Pielke Sr. Questions
    Tom Curtis - I have framed two distinct testable scientific hypotheses. The relative importance of enhanced GHG forcing and ocean acidification (from added CO2) is certainly included. We will just have to disagree and move on, if you will not present two testable hypotheses of your own which we can discuss.
    Moderator Response: [John Hartz] If this were a conference call, I would politely ask Dr. Pilke and Tom Curtis to continue this discussion off-line. Having said that, let's move the discourse to other topics that have not yet been addressed in any depth on this comment thread, e.g., the metrics for measuring climate change.
  8. SkS Responses to Pielke Sr. Questions
    KR - You write "I have to strongly disagree (as I have before, on other venues) with your emphasis on regional effects over global effects." The weather that affects people is regional and local in scale. The global average tells us little, if anything, about weather patterns such as droughts, floods and so forth. It may be that a higher global average surface temperature is correlated with changes in frequencies in these extreme weather events; the models have not shown skill in such a prediction. Regardless, however, it is the changes in regional and local climate statistics that matter and that is where our focus should be.
  9. SkS Responses to Pielke Sr. Questions
    I am very surprised to see a scientist even consider asking question number three. Why would you only look at a small subset of data, unless you are motivated by what you wish to find.
  10. SkS Responses to Pielke Sr. Questions
    MODERATOR: - I get the impression that the steam has run out for Issues 1 & 2. Would you please formally announce that the topic is shifted to Issue 3: on preferred diagnostics for global warming? - I note that Dikran Marsupial's post at #44 seems relevant to the new topic. - Of course, if Dr. Pielke has more to say on 1 & 2, we can re-adjust.
  11. SkS Responses to Pielke Sr. Questions
    Having read this thread, and observed the efforts of Dr. Pielke to avoid addressing simple observations and interpretations with simple forthright statements (as opposed to creating the impression that our understanding and policy should be centred around nit-picking issues of semantics and sentence construction.... ...I cannot recommend highly enough the short talk by Dr. Scott Denning at the recent Heartland Institute "Climate Science" meeting. Dr. Denning knows how to call a shovel a shovel, and cuts through exactly the sort of prevarication and nit-picking that is such a drain on productive discourse and policy making. Can't be recommended highly enough.
  12. SkS Responses to Pielke Sr. Questions
    I think I understand Prof Pielke's scientific desire to say things are alot more complicated than just CO2, and even just Greenhouse Gases. I agree land use changes, aerosols, black carbon, sulphates etc have important impacts. My main point, though, is that if coal, and other fossil fuels, were used less then many of these issues would be reduced. CO2 is being used as a proxy for Carbon, which is being used as a proxy for fossil fuels - which contain sulphates, emit aerosols, and cause carbon black. This is about framing - and reading the different statements I find the nuances interesting, but a bit too nit-picking, but hey this is a debate about science where details matter. But basically isn't the hypothesis: Although the natural causes of climate variations and changes are undoubtedly important, the human influences are significant and increasing due to population growth and increased energy output with economic growth. Human influences are dominated by our use of fossil fuels causing the emissions into the atmosphere of both greenhouse gases, the most important of which is CO2, and aerosols. The adverse impact of the use of fossil fuels on regional and global climate, along with land use change from increasing population, constitutes the primary climate issue for the coming decades. This tries to cut away from the nit-picking science and goes to the basic causes - our economy is based on fossil fuels, our population is growing and increasing its use of these fuels and this is effecting the climate.
  13. Hockey stick is broken
    Albatross, looking at http://www.cru.uea.ac.uk/cru/people/briffa/qsr1999/qsrfig1.csv it has the series result only without any supporting data or metadata (e.g. # of trees). Here's the data released roughly 10 years later: http://www.cru.uea.ac.uk/cru/people/melvin/PhilTrans2008/YamalADring.raw Please let me know if I've missed something, but it seems cut and dry to me.
  14. Dikran Marsupial at 17:55 PM on 21 September 2011
    SkS Responses to Pielke Sr. Questions
    Prof. Pielke, please could you comment on the paper by Douglass et al. Douglass D. H., Christy, J. R., Pearson, B. D. and Singer S. F., "A comparison of tropical temperature trends with model predictions", International Journal of Climatology, Volume 28, Issue 13, pages 1693–1701, 15 November 2008 This paper purports to show that observed tropical trophospheric temperatures are inconsistent with model projections, however the statistical test they used is obviously flawed (it would reject the theoretically ideal model which had perfect physics, infinite temporal and spatial resolution and an infinite ensembe to give a perfect characterisation of internal climate variability). Do you agree that this paper is flawed and the conclusion not supported by the evidence?
  15. Dikran Marsupial at 17:18 PM on 21 September 2011
    Climate is chaotic and cannot be predicted
    Dana69 (on another thread) wrote: "If climate is deterministic in nature you could have reasonable assurance of the outcomes. If more stochastic (governed by the laws of probability) it would be problematic. ... Seems most arguers here land on the deterministic side." Both weather and climate are deterministic. A chaotic system is one that is deterministic, but so sensitive to initial conditions that it is essentially unpredictable beyond a short prediction horizon. STochastic processes are not necessarily a problem either, the field of statistics (the mathematics of stochastic processes) is well developed and we have means of dealing with it. One of them is Monte Carlo simulation, which is the basis for both weather forecasting and climate projection (although used in different ways). "They do not specifically say so, but the reference to Lorenz and the use of “attractor” imply that chaos theory is being invoked here not determinism." If you knew anything about chaotic systems, you would know that they are deterministic. A little bit of knowledge can be a dangerous thing if one is not fully aware of the limits of ones knowledge. I suspect the scientists who wrote that section of the IPCC reports have a very sound grasp of chaos theory and understand very well what it implies for climate projection.
  16. SkS Responses to Pielke Sr. Questions
    The Games People Play ... I suspect Pielke is playing games here. Although I cannot speak on behalf of Sks on this post, I make the following observations. If a climate skeptic puts forward two alternative “framings” of the debate, neither should be given blanket endorsement. The best response would be for Sks to formulate its own preferred “framing” of the issues. It is likely that Pielke thinks he can entrap Sks, cherry-picking words or phrases in Sks’s response in an effort to discredit it, outside of the context of Sks’ well structured and comprehensive analysis of the evidence. Compare the alternative texts and spot the differences. I believe Sks should be prepared to do a phrase by phrase analysis, endorsing one or other option for each phrase (or neither) as appropriate. Consider the alternative texts in Pielke’s second question: Mike Hulme i: human greenhouse gas emissions Mike Hulme ii: human greenhouse gas emissions, land use changes and aerosol pollution The first is correct because the climate is driven by CO2. The major forcings are CO2, methane, etc. and their positive feedback through water vapour, as illustrated diagrammatically on the Sks site. However, the second wording might be seen as more comprehensive in that it specifically includes greenhouse gases and aldebo changes associated with agriculture as well as the negative forcing of aerosols. Therefore, in relation to this phrase alone, I agree with Dana in saying “the second framing is probably more appropriate, as addressing climate change will involve more than just CO2 emissions reductions”. Mike Hulme i: climate changes that cannot be explained by natural causes Mike Hulme ii: which exacerbate the changes and variability in climates brought about by natural causes. I think Pielke sees the first as a solid endorsement of AGW, while the second is a softer partial endorsement of AGW. For this phrase, would not SKs back the first? Mike Hulme i: we are causing it Mike Hulme ii: humans are contributing to climate change This is similar to the above example. The first as a solid endorsement of AGW, while the second is a softer partial endorsement of AGW. Again, would not SKs back the first? Mike Hulme i: it is happening right now Mike Hulme ii: it is happening now and in the future for a much more complex set of reasons than in previous human history The first as an emphatic statement that climate change is underway (as we are witnessing in the Arctic). The second is a softer statement, and seems to suggest a more uncertain trajectory for global warming because of “complexity”. Again, should not Sks reject this fudge language and back the first? Do you now see the trap? In the first option we encounter, I think Pielke entices the reader to endorse the second wording. He seeks to get a simple endorsement of “Mike Hulme ii”, in order to trap the reader (and potentially Sks) into endorsing by implication the second wording for the remaining options. As I have argued above, I think Sks would be much more likely to back the first phrase in these latter choices. Perhaps Dana should qualify his response to Pielke’s second question. The same phrase by phrase analysis should be applied to Pielke’s Hypothesis 2a and Hypothesis 2b, but I leave that as an exercise for the reader. Oh the games people play now Every night and every day now Never meaning what they say now Never saying what they mean …
  17. Chasing Pielke's Goodyear Blimp
    "Christy's Twisties". I like it! :-D nealjking: I dunno, I think you'd find it difficult to find a word that I found offensive but you didn't... :-P (not that I'm challenging you to!) Having said that - considering the robustness (there's that word again! ;-) of the debate on the topic, it seems clear there's a significant part of SkS' readership that finds the term offensive (as puzzling as that is to some of us). So maybe it should be changed. Either way, it's John's call, methinks.
  18. SkS Responses to Pielke Sr. Questions
    Dr. Pielke assures us that land-use change is a "first- order" climate forcing. But nowhere, at least where I can find does he indicate the magnitude of this forcing in W m-2 (with error bars) or in terms of his preferred units, Joules. He appears to be stating a fact without providing a quantifier to justify his assertion. Some estimates of land-use change did appear in WG1 of TAR in 2001. They say: "Following Hansen et al. (1997b), Shine and Forster (1999) recommended in their review a value of -0.2 Wm-2 with at least a 0.2 Wm-2 uncertainty. We adopt those values here for the best estimate and range, respectively; however, in view of the small number of investigations and uncertainty in historical land cover changes, there is very low confidence in these values at present." Even if one takes the upper range, one is probably looking at <0.5 W m-2, quite small compared to the expected forcing from GHGs and tropospheric ozone, for example. Also, note the uncertainty-- hardly a given as suggested by Dr. Pielke. As evidence of the importance of land-use change on climate (he does not specify "global" or regional", but it is made in the context of "future behavior of Earth’s climate"), Dr. Pielke in his EOS essay cites Takata et al. (2009). However, that is a regional modeling study using an AGCM. So I sense a double standard by Dr. Pielke when it comes to the value of the AOGCMs. Maybe Dr. Pielke would like to comment on the paper by Sitch et al. (2005)? I and others have no doubt that land-use and land cover change can have marked local and even regional effects on weather and climate, but remain unconvinced that human land-use change is currently (or in the future will be) a first-order driver of global climate and TOA radiation imbalance. That may have been the case in the late 19th and early 20th centuries when the forcing from GHGs was much smaller. Dr. Pielke does not also seem to appreciate that changing climate in itself can also bring about land-use change as eco zones change. There is also an interesting self-contradiction in Dr. Pielke's logic when it comes to his argument about what he considers to be first-order climate forcings and how one monitors climate change, but I'll save that for later. And, contrary to claims made by Dr. Pielke, the role of land use is not being ignored or played down in the IPCC assessment reports. From AR4, "Understanding land-use and land-cover changes is crucial to understanding climate change. Even if land activities are not considered as subject to mitigation policy, the impact of land-use change on emissions, sequestration, and albedo plays an important role in radiative forcing and the carbon cycle." All for now.
  19. SkS Responses to Pielke Sr. Questions
    Readers, While discussing hypotheticals and semantics of carefully crafted hypotheses is intriguing, it is for the most part not constructive. And despite claims to the contrary by Pielke et al. (2009), the hypotheses being discussed are not helpful in expediting taking meaningful action on AGW. In fact, I would argue that in this case the hypotheses were presented to fabricate debate, exaggerate uncertainty and foster doubt. With regards to the "hypotheses" presented in Pielke et al. (2009) In his oral testimony to the House of Representatives Energy and Commerce Committee hearing on "Climate Science and EPA’s Greenhouse Gas Regulation" in March, 2011, Dr. Pielke is on the public record saying: "With respect to climate change, in 2009 18 Fellows of the American Geophysical Union accepted an invitation to join me in a paper where we discussed three different mutually exclusive hypotheses with respect to the climate system:" And "Hypothesis 2b is the IPCC perspective. In our EOS paper, we concluded that only Hypothesis 2a has not been refuted." He then provides this citation: Pielke Sr., R., K. Beven, G. Brasseur, J. Calvert, M. Chahine, R. Dickerson, D. Entekhabi, E. Foufoula-Georgiou, H. Gupta, V. Gupta, W. Krajewski, E. Philip Krider, W. K.M. Lau, J. McDonnell, W. Rossow, J. Schaake, J. Smith, S. Sorooshian, and E. Wood, 2009: Climate change: The need to consider human forcings besides greenhouse gases. Eos, Vol. 90, No. 45, 10 November 2009, 413. Copyright (2009) American Geophysical Union. Dr. Pielke appeals to his own authority and that of the AGU ("18 Fellows of the AGU") when he discusses the where the hypotheses first appeared. Now the way that is presented to the casual reader it sounds looks very much like a citation for a journal paper does it not? Academics and research scientists alike mean "journal paper" when they say "paper". Well that 2009 citation is not a "journal paper", it was published in the "Forum" section of EOS, the official newspaper of the AGU. The guidelines for EOS are clear they say that: "Eos does not publish original research results" And "Eos is a newspaper, not a research journal" Now maybe things were different when their opinion piece was published in EOS in 2009. If so my concerns are unfounded, and I sincerely apologize for bringing it up. But if not, it could be fairly argued that Dr. Pielke is misleading many people (inlcuding members of the House of Representatives) into thinking that these hypotheses appeared in a peer-reviewed paper in an AGU journal. As a member of the AGU (American Geophysical Union) I take strong exception to him doing so, and I urge him to address this matter. Additionally, Dr. Pielke does not in his testimony in March 2011 clearly indicate that dealing with AGW and reducing GHGs emissions is urgent and that prompt action must be taken. Why not? Not surprisingly, his personal position is quite a different view from the policy statement issued by the AGU on behalf of its almost 60,000 members from over 130 countries who are members of the AGU. That statement says very clearly: "If this 2°C warming is to be avoided, then our net annual emissions of CO2 must be reduced by more than 50 percent within this century." One last intriguing observation on Dr. Pielke's testimony. As someone with numerical modeling experience, I'm confused by Dr. Pielke's (who is a modeler) claim that "Models themselves are hypotheses", in his book "Mesoscale Meteorological Modeling" which is on my bookshelf here, he says on page 1 that "....it is necessary to understand the basic physical and mathematical foundations of the models...". Quite different from what he said in his testimony. He then says "There is no way to test hypotheses with the multi-decadal global climate model forecasts for decades from now as step 2, as a verification of the skill of these forecasts, is not possible until the decades pass." This leads me to conlcude that Dr. Pielke is of the opinion that models are nothing more than untestable hypotheses...it would be a great shame if he thinks that his life's work amounts to that.
  20. SkS Responses to Pielke Sr. Questions
    Given Dr. Pielke's statements what would people think of putting together a joint statement from "warmists" and "skeptics" on the need for alternative energy development and moving toward a low carbon economy?
    Moderator Response: [John Hartz] SkS is all about getting the science right, not about representing a particular point of view.
  21. SkS Responses to Pielke Sr. Questions
    Tom Curtis and Dr. Pielke: You may choose to argue fine differences of meaning between your formulations of dichotomy. What I am failing to see is any value-add over what I'm saying right here: "I think we can agree that there are land-use issues as well as atmospheric additives that impact on climate. Land-use issues are under more local control, whereas atmospheric additives need to be considered from a global perspective as well. I don't think we can afford to dismiss any of them."
  22. SkS Responses to Pielke Sr. Questions
    Okay, I am curious. If GHG is not the main forcing, then the only other candidate "forcing" that I can think of would be a reduction in industrial aerosols since 1945 if this can be regarded as a forcing. Its not particularly useful forcing since we dont want to make the air dirty and the aerosols are associated with GHG gas release anyway.
  23. SkS Responses to Pielke Sr. Questions
    Dr Pielke @32, unfortunately I cannot accept either of your reworded hypotheses, which now constitute a false dichotomy. Specifically, the most important challenges in the coming century are the global issues of enhanced GHG forcing and ocean acidification. This perspective is not represented by either of your two amended hypotheses. With respect to Neal King (@34), I think the word-smithing is important. As originally stated, the vague distinction encouraged people to see denial of 2a as the unreasonable assertion that non-GHG forcings, and regional effects are irrelevant for policy purposes. Regardless of Dr Pielke's intentions if formulating the hypothesis, we all know there are many "skeptics" unscrupulous enough to try and turn that vagueness into an ad-hominen attack on the consensus understanding of climate science. Dr Pielke's further amended framing of the issue, in contrast, precludes a global focus on what is fundamentally a global problem. Further, I believe that Dr Pielke's difficulty in framing the two hypotheses stems from an unwarranted assumption that certain commonly recognized facts are inconsistent with the consensus understanding of climate science. By not consistently and untendentiously framing the issue, he sneaks those assumptions into the discussion with out having to explicitly formulate and defend them.
  24. Hockey stick is broken
    Eric @120, "Skywatcher, "ancient" only because Briffa did not release his data for almost 10 years" SImply not true. You are, again, believing uncritically what Mr. McIntyre is feeding you. I could show you why you are wrong, but I would prefer that you be a true skeptic and discover the truth on this matter yourself. I'm saddened by this Eric, I used to consider you one of the more informed and reasonable "skeptics", but your actions of late have soured that.
  25. SkS Responses to Pielke Sr. Questions
    Dr. Pielke - I have to strongly disagree (as I have before, on other venues) with your emphasis on regional effects over global effects. That is only reasonable if the regional variations are sufficient to mitigate the global effects of rapid climate change. There are certainly huge variances across different regions of the world, but if the average of those regions change - with concomitant effects/costs on agriculture, sea level of coastal regions (where most of humanity resides), etc., regional variations will certainly not save us those costs. There's certainly no evidence for regional variations overriding global effects in the majority of the areas that are/will be affected. And, in fact, mitigating the global effects will mitigate regional changes as well. --- My 2 cents on the anonymity issue? I'm not interested in argument by authority, implied or otherwise - I would much rather people judge what I say by content.
  26. SkS Responses to Pielke Sr. Questions
    I propose we declare the topics of anonymity and harassment as "off topic."
  27. SkS Responses to Pielke Sr. Questions
    Dr. Pielke, #32: I can't get very excited about the word-smithing that's been going on so far. I stick with what I said at #21.
  28. SkS Responses to Pielke Sr. Questions
    It is interesting to see that Dr Pielke thinks that climate sensitivity is not important (Drs Spencer and Lindzen might wish to disagree). Climate senstivity tells us how much the world is warming in relation to the added CO2, and whether this warming is going to continue into the future. Temperature increases are logcally linked to many of the key impacts of climate change - increased severe precipitation events (water vapour), more intense droughts (heat and drying), snow and ice loss (water availability, albedo), sea level rise. These are all observed. Failures in GCM estimates of regional climate (claimed in Pielke et al's 2011 manuscript) is not an excuse to ignore the observed trends in snow, ice, water vapour, sea level and extreme events. These trends will be worse with high climate sensitivity. All of these changes have very real local effects, and will impact your decisions whether you're a Texan or Pakistani farmer, or if your water comes from dwindling snows, or if you live within a metre or two of sea level, for example. If climate sensitivity were low, we'd have little reason to think that the magnitude of each of these products of higher temperature would be likely to increase in the near future. As sensitivity is high, clearly demonstrated by a wide variety of sources (including the important palaeoclimate and geological-scale estimates that incorporate all feedbacks), summarised in Knutti and Hegerl 2008, we have extremely good reasons to believe that these impacts will increase as global temperature continues to rise. It's a pity Dr Pielke does not think climate sensitivity is important, as it would help him to encourage policymakers to develop more effective adaptation and mitigation strategies. I would fully endorse Tom's comment in #31 re threats to individuals, and would be interested in Dr Pielke's response.
  29. Hockey stick is broken
    Albatross the issue is not what Dr Briffa thinks or says now, the issue very narrow: whether anyone should have used the Briffa-Yamal series in building reconstructions between 2000 and 2009 when he finally released the raw data, when there were other series created with more data. CB, is there a thermometer in Yamal? Briffa used the HadCrut grid cell which is not remotely similar to most local instrument measurements (mostly flat in the last part of the 20th century). Even for that grid cell temperature, there are other better-correlated series. Skywatcher, "ancient" only because Briffa did not release his data for almost 10 years. A handful of trees matching up to a coarse grid cell is not a sign of agreement particularly when other series have a better match to local temperatures (not gridded) temperatures. My first two links in #91 both show that.
  30. SkS Responses to Pielke Sr. Questions
    Tom Curtis If you feel this separates them better, lets use these two hypotheses Hypothesis 2a: Although the natural causes of climate variations and changes are important, the human influences on regional climate are significant and involve a diverse range of first-order climate forcings, including, but not dominated by, emissions into the atmosphere of greenhouse gases including CO2. Most, if not all, of these human influences on regional climate will continue to be of concern during the coming decades. Hypothesis 2b: Although the natural causes of climate variations and changes are undoubtedly important, the human influences on regional climate are significant and are dominated by the emissions into the atmosphere of greenhouse gases including CO2. The adverse impact of these gases on regional climate constitutes the primary climate issue for the coming decades." Please try to wordsmith further is you feel edits are still needed. I conclude (as Mike Hulme also agrees), policy responses would differ significantly depending on which hypothoesis is not rejected. From my view, and that of an increasing number of my colleagues, the second hypothesis has been rejected.
  31. SkS Responses to Pielke Sr. Questions
    With regard to anonymity of comment, it is the simple fact of the matter that publicly speaking out on AGW in defiance of the various "skeptical" misinformation machines has resulted in climate scientists being subject to various forms of public harassment including, but not limited to abusive emails, death threats, and illegal hacking and distribution of private correspondence. Dr Pielke has not, to my knowledge, condemned such acts, and does continue to associate with people who have endorsed them to various degrees. This should not be read as approval, but it is inconsistent with any vehement disapproval of such tactics. To object to people choosing to not make themselves targets of abuse, death threats and illegal hacking is therefore, disingenuous at best, and hypocritical at worst. Given Dr Pielke's stated concerns about anonymity, can we expect from him a clear condemnation of those like Anthony Watts and Christopher Monckton who variously practise or endorse various (though not necessarily all) of the above forms of harassment?
  32. SkS Responses to Pielke Sr. Questions
    Dana Nuccitelli - Thanks for clarifying.
  33. SkS Responses to Pielke Sr. Questions
    Dr Pielke @19, as you are the author of the supposed dichotomy, it is for you to reformulate the dichotomy, not me. As an initial step, you can make the following (highlighted) changes to make the to statements formally contraries:
    "Hypothesis 2a: Although the natural causes of climate variations and changes are undoubtedly important, the human influences are significant and involve a diverse range of first-order climate forcings, including, but not limited to, the human input of carbon dioxide (CO2) but not dominated by, emissions into the atmosphere of greenhouse gases, the most important of which is CO2. Most, if not all, of these human influences on regional and global climate will continue to be of concern during the coming decades. Hypothesis 2b: Although the natural causes of climate variations and changes are undoubtedly important, the human influences are significant and are dominated by the emissions into the atmosphere of greenhouse gases, the most important of which is CO2. The adverse impact of these gases on regional and global climate constitutes the primary climate issue for the coming decades."
    As you also seem to be defending the claim that regional effects are more significant than global effects, you may wish to explicitly state that as part of 2a. Finally, you need to clarify what you mean by "dominate". As I do not know your thinking I cannot do that for you. However, of the four possible meanings in my post, I feel confident in stating that most commentators here would reject 2b if "dominate" is interpreted as "That the GHG forcing is sufficiently greater than the sum of all other forcings that for practical (policy) purposes, the other forcings can be ignored". I suspect most would also consider a gloss of "dominate" as "That the GHG forcing is greater than any other individual forcing" as being too weak. Having said that, neither is entirely satisfactory as stated in that they do not sufficiently discriminate between positive and negative effects, and gross and net effects. Specifically, it is clear IMO that the absolute value of the net forcing of GHG is greater than the absolute value of the net aerosol forcing; but it is may be less than the sum of the absolute values of the gross effects (positive and negative) of aerosols. Further, given the distinction between global and regional effect is important to your understanding of dominance, it is not certain any of my glosses captures even your approximate meaning. As it is you who asked the question, it is for you to clarify these points.
  34. CERN - Saying Nothing About Cosmic Ray Effects on Climate
    tblakeslee#74+: "it is conceivable that these variations are related to varying phenomena in the sun's activity" That sounds remarkably tentative. Presumably these variations are ongoing over a very long time. Where are the prior warming episodes that correspond to these cycles? Why has the current warming managed to coincide with a massive increase in atmospheric co2? "GCRs don't need to be decreasing to cause warming." That's the Svensmark consensus. Are you skeptical? "Remaining at a constant low level reduces cloud cover causing a gradual rise in temperature which is cumulative." I have no idea what that means or why it would work that way. Unfortunately for this hypothesis, there is still no direct proof that GCRs have anything to do with cloud cover.
  35. Philippe Chantreau at 11:01 AM on 21 September 2011
    SkS Responses to Pielke Sr. Questions
    I would advise all to not pay the least attention to the anonymous thing. It is a common tactic used at WUWT to avoid dealing with the substance of comments. SkS comment policy has no restrictions on the use of real names vs. screen names. As far as I can remember, no comment here was ever dismissed on the basis that the poster was anonymous, regardless where his/her opinion leaned. Of course, one can decide to ignore the content of a comment, even if perfectly valid, only because the commenter remains anonymous; it is a choice everyone is free to make. Considering the insults and threats from skeptics that are not so unusual in this debate, I find it perfectly understandable also that some would choose to remain anonymous.
  36. SkS Responses to Pielke Sr. Questions
    I should also note that while I drafted up this post and contributed significantly to it, a number of SkS contributors provided input as well. It was another consensus effort.
  37. SkS Responses to Pielke Sr. Questions
    Dr. Pielke, I am not anonymous. As Bibliovermis notes in #23, sometimes I include my full name, sometimes I don't. However, my background information is provided in the Skeptical Science Team link provided by NewYorkJ in #25.
  38. SkS Responses to Pielke Sr. Questions
    Something we can all agree on: The Skeptical Science Team (About -> Team) includes a diverse range of contributors, including, but not limited to, John Cook.
  39. SkS Responses to Pielke Sr. Questions
    I agree with John Hartz I think the replies to Dr Pielke's questions and the SkS questions put to him are sensible and well considered. Comments and responses to both will hopefully prove instructive and interesting - though I have always regarded both Pielkes as "skeptics". This of course does not mean the product of a SkS-Pielke dialogue will be predictable - but will it be fruitful?
  40. SkS Responses to Pielke Sr. Questions
    Dr. Pielke, Dana1981's full name is at the bottom of the rebuttal articles that he writes. e.g. Not So Cool Predictions. (written by Dana Nuccitelli [dana1981]) You do realize that casting aspersions on the content based on the pseudonymity of the author is an ad hominem, right?
  41. SkS Responses to Pielke Sr. Questions
    Your answer for glacier mass balance is not correct the mass balance loss as reported to the WGMS and by the WGMS and noted by decade for the BAMS state of the climate series in 2010 is greater than noted above. In the 1980's it was -180 mm per year not decade. In the 1990's it was -370 mm per year, in the 2000's it was -630 mm per year.
  42. CERN - Saying Nothing About Cosmic Ray Effects on Climate
    The CGRs control cloud formation but it takes time to change the temperature of the earth and oceans. Steady low CGR levels reduce cloud formation but it takes years of cloudless days to get the oceans and earth heated up.
  43. SkS Responses to Pielke Sr. Questions
    From a more practical, less philosophical perspective: I think we can agree that there are land-use issues as well as atmospheric additives that impact on climate. Land-use issues are under more local control, whereas atmospheric additives need to be considered from a global perspective as well. I don't think we can afford to dismiss any of them.
  44. SkS Responses to Pielke Sr. Questions
    Dr. Pielke, Hypothesis A states "the human influences are significant and involve a diverse range of first-order climate forcings, including, but not limited to, the human input of carbon dioxide (CO2)." which would be consistent with IPCC AR4. Hypothesis A does not state what the other influences besides CO2 are, and does not speak to land use changes, as you assume above. As you can see from the radiative forcing figure referenced in #13 and #14 (also SPM.2 in the Summary for Policymakers WG1), the human influences include CO2, N2O, Halocarbons, ozone, black carbon, and aerosols. The IPCC and the evidence is also consistent with CO2 being the single-most important anthropogenic contributor and is consistent with Hypothesis B (although as I've noted in #13, the scope of the IPCC report tends to inevitably underestimate the severity of long-term impacts of the human addition to atmospheric CO2). What I'm not sure you're understanding (but what Hulme appears to understand) is that these statements are not remotely close to being Mutually exclusive.
  45. SkS Responses to Pielke Sr. Questions
    Tom Curtis - I invite you to reframe into two "oppositional" testable hypotheses. The 19 co-authors of our paper [all Fellows of the AGU] concluded the ones we presented are distinct. However, I welcome to use your comment above to do this if you feel they are not separate enough. On your comment, "To that purpose, perhaps you could indicate if you disagree with the relative forcings indicated by the IPCC AR4, and if so by how much. They certainly seem to indicate that the sum of GHG is currently the dominant forcing of climate change" this is only true from the IPCC figure in terms of the global average radiative forcing, even if you accept their values. You stated that the "the sum of GHG is currently the dominant forcing of climate change". As one counter example, in terms of their role on weather patterns, and thus on climate, see Matsui, T., and R.A. Pielke Sr., 2006: Measurement-based estimation of the spatial gradient of aerosol radiative forcing. Geophys. Res. Letts., 33, L11813, doi:10.1029/2006GL025974. http://pielkeclimatesci.wordpress.com/files/2009/10/r-312.pdf In terms of CO2, and its fractional role in terms of the global average radiative forcing, I provided my estimate, based on the available literature, in my answer to one of dana1981's questions [note: it would be nice to know who dana1981 is; it is unfortunate that anyone feels they need to be annoymous].
  46. Hockey stick is broken
    Eric #112: Why do you waste your time with ancient, disproven arguments from McIntyre? I'll pick on one of your statements: "It is equally possible that those faster growing trees are impacted positively by another unknown factor." Sounds a lot like "unknown unknowns" to me. You're arguing that these trees agree with the instrumental/proxy record both recently and farther into the past millennium, yet you think there's a 50/50 chance that the trees are measuring the wrong thing but accidentally coming out with the right result? For that to be true, you need to believe two things: 1) that the trees measured past climate proxies well, yet broke down in the past 50 years, like the trees of the divergence problem. 2) that the trees which agree with the recent instrumental record have, within the last 50 years, picked up a new signal, not present in their palaeo records which drives their temperature record up very like the instrumental series. Or you could simply agree that these trees are succeeding in picking up the recent temperature series as they did with pre-1950 temperatures. In that way, the trees agree with many other independent proxy records as well as instrumental temperatures. It's hardly 'equally probable', that the trees have these two suspiciously coincident unknowns. It shows what you get if you take your information from McIntyre...
  47. SkS Responses to Pielke Sr. Questions
    NewYorkJ - The 2007 IPCC focuses on CO2 mitigation; e.g. see Contribution of Working Group III to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, 2007 B. Metz, O.R. Davidson, P.R. Bosch, R. Dave, L.A. Meyer (eds) Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA. The physical science basis focuses on added greenhouse gases, and a top-down global perspective as given in Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, 2007 Solomon, S., D. Qin, M. Manning, Z. Chen, M. Marquis, K.B. Averyt, M. Tignor and H.L. Miller (eds.) Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA. I am pleased, however, that you see the need to move towards hypothesis 2a.
  48. SkS Responses to Pielke Sr. Questions
    John Hartz - The term "broadly consistent" covers a lot of territory. I certainly would not write the IPCC connection that way. Regardless, however, his key conclusion is that, as he writes [what are really a statement of hypotheses 2a and 2b) ”….these two different provocations – two different framings of climate change – open up the possibility of very different forms of public and policy engagement with the issue. They shape the response. The latter framing, for example, emphasises that human influences on climate are not just about greenhouse gas emissions (and hence that climate change is not just about fossil energy use), but also result from land use changes (emissions and albedo effects) and from aerosols (dust, sulphates and soot). It emphasises that these human effects on climate are as much regional as they are global. And it emphasises that the interplay between human and natural effects on climate are complex and that this complexity is novel.” A focus on the radiative forcing of added CO2 as the dominate environmental threat is not supported by the scientific evidence. Policies that focus on that single issue which result in negative effects on other environmental and social concenrs is not good policy, in my view.
  49. CERN - Saying Nothing About Cosmic Ray Effects on Climate
    tblakeslee - Clouds respond to temperatures in a matter of hours or at most days. No visible trend or offset, as you claim in GCR's has been observed corresponding to recent temperature changes. Your hypothesis still does not fly.
  50. SkS Responses to Pielke Sr. Questions
    (It looks like Tom Curtis is already starting on that approach, so I'll get out of his way.)

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