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Comments 74301 to 74350:

  1. SkS Responses to Pielke Sr. Questions
    VeryTallGuy @75 Well said. I also noticed Pielke's devotion to balance in his "We need more reaching out between the different groups. The Heartland Institute and Skeptical Science have this reaching out in common". You know, the "two equal sides"-tactic. That said, I think Pielke sr. actually this time has answered at least some of the questions. Kudos to Dr. Pielke for that.
  2. SkS Responses to Pielke Sr. Questions
    pbjamm @70, you raise an interesting point. I believe the most important cause of the rapidly retreating arctic sea ice extent (and volume) is the reduced albedo from the melting of sea ice and reduced snow extent. While technically a feedback rather than a forcing, that is itself a regional event so this is one case where Dr Pielke can claim that regional factors are more important in the particular evolution of the regional climate than are global factors. To see this, we need only compare the distinct reaction between Arctic and Antarctic. Having said that, it still remains true that the initial reduction in sea ice extent was a consequence of the enhanced greenhouse effect, a global factor. So even when regional factors dominate the particular evolution of regional climate (an hypothesis 2a situation) understanding of the long term evolution of the regional climate may only be understandable by reference to global factors.
  3. SkS Responses to Pielke Sr. Questions
    Seems to me that Pielke’s case is in many ways a tour de force of familiar skeptic tactics. Notably 1) “If we don’t know everything, we must know nothing” fallacy. Expertly done with the "as we don’t know detailed regional impacts, global warming is irrelevant” line. 2) Cherry picking of datasets. Firstly, brilliant delivery on the “OHC is the only measure that counts” issue being at the same time basically scientifically sound (most of the heat does, of course, go into the ocean) yet at the same time spectacularly myopic in ignoring the rather inconvenient multiple other lines of evidence. Secondly, in using only the most recent data from ARGO on OHC rather than the whole record. 3) Shamelessness. Showing truly admirable chutzpah in switching seamlessly from the UAH temperature to OHC as preferred metric when UAH ceased to show the right trend. 4) Obfuscation. When challenged, don’t answer the question but move on. Magnificent examples in the current brouhaha: moving the discussion on from his attack on SKS to his preferred topic of the OHC issue. Also throughout the thread referencing largely irrelevant papers rather than actually answering questions. 5) Avoidance (via taking the moral high ground). He has carefully avoided defending the obviously unjustifiable elements of Christy’s testimony - by claiming to want to move the discussion on the science. And who could argue with that, on Skeptical Science? You've got to hand it to him, he's a class act
  4. One-Sided 'Skepticism'
    Critical mass "My point is that the authors of this site seem to automatically accept that a pro-AGW scientist such as Dr Trenberth or Dr Hansen will get it right (even when they disagree with each other) and if one of the 'usual suspects' says something different then they generally must be wrong." Whatever his past successes, Dr Lindzen's viewpoint on climate sensitivity is not widely accepted in the scientific literature because observations and modeling results do not bear it out. Predictions based on his viewpoint also fail spectacularly to represent past trends in temperature. If you read the linked threads, you find that SkS is merely reporting the evidence for and against his positions. It does not presume he is wrong a priori because he is a "skeptic." It shows he is likley wrong because his positions put him at odds with the data and our understanding of physics (based on lots of data). The same can be said for many of the other "skeptic" positions. The evidence for AGW is so overwhelming that you are almost forced to argue that the evidence is wrong to hold an opposite opinion. I guess that's one reason one often hears AGW skeptics spout conspiracy theories about data manipulation. As for intentions, I cannot explain why Lindzen refuses to back down on his positions, nor can most of the climate scientists I personally know (note that I am not one). As DM notes, it does on occassion happen that brilliant scientists head down the wrong track, for whatever reason, sometimes spectacularly so. Past success does not guarantee future success. Though it does warrant a measure of personal respect, it does not excuse his ideas from critical inspection.
  5. SkS Responses to Pielke Sr. Questions
    If regional climate is governed by regional land use changes then what exactly is happening in the Arctic to cause the sea ice to melt?
  6. SkS Responses to Pielke Sr. Questions
    In all seriousness, there may be aspects of issues which we can agree to, and other aspects that we cannot - at least not in one session of discussion. In that case, it may be useful to document items of agreement, which can be recorded; and items for further discussion (if that seems to be fruitful). I believe Dana is taking a few notes, so maybe if we can spell out the agreements and isolate the items where no further progress is likely today, we will be able to cover more ground before everyone runs out of steam. Does that make sense to people?
    Moderator Response: [John Hartz] I concur.
  7. Dikran Marsupial at 00:36 AM on 22 September 2011
    One-Sided 'Skepticism'
    critical mass wrote: "but I find it hard to explain why a scientist like Dr Lindzen gets it right in over 100 papers and then goes off the rails in the critical area of climate sensitivity and then refuses to retract or acknowledge what others claim as errors." Actually that is all too common a career trajectory, it is not difficult to think of excellent scientists that have gone badly wrong when they have strayed even slightly from their field of primary expertise. Scientists are very prone to Dunning-Kruger, you get used to being an expert but most of the time you still have to start at the beginning when moving into a new field, which doesn't come easily to some. There is no need to question motivation, and I would avoid doing so as (i) it is pretty irrelevant as to whether the science is correct and (ii) it (quite rightly) contravenes the comments policy.
  8. SkS Responses to Pielke Sr. Questions
    Moderator - To be more specific, in my comment here I was considering the regional/global distinction, which received a 'move along' admonition, not the phrasing of 'which statement do you agree with'. I consider posing repeated statements that you attempt to get agreement to a rhetoric exercise, and am (personally) quite done with that. Cattle prods may be appropriate there. But as a different issue, framing the question of climate as regional, when the changes in regional climate are driven by global climate change, is disingenuous. And (again, my opinion) an attempt to avoid dealing with those global issues. And I think Tom Curtis agrees with me, and has expressed it quite clearly.
    Moderator Response: [John Hartz] Given the structure of Dana's article, it was inevitable that this comment thread would contain multiple comment threads. My concern is that we not create a Gordian knot.
  9. One-Sided 'Skepticism'
    #200 chris DM #199 and you make some good points - but I find it hard to explain why a scientist like Dr Lindzen gets it right in over 100 papers and then goes off the rails in the critical area of climate sensitivity and then refuses to retract or acknowledge what others claim as errors. There is either an issue of bad faith or political motivation here or an irreconcilable difference of opinion. My point is that the authors of this site seem to automatically accept that a pro-AGW scientist such as Dr Trenberth or Dr Hansen will get it right (even when they disagree with each other) and if one of the 'usual suspects' says something different then they generally must be wrong. Michael Sweet #204 mades this point for instance: "Currently Dr. Hansen and Dr. Trenberth are debating about "missing heat" versus aerosol cooling. It seems likely that one of them will be wrong in the end. Since neither has made an outrageous claim, when the energy path is finalized neither will look bad". I would suggest that had the likes of Dr Lindzen made a claim like the 'delayed Pinitubo rebound effect' as a contributor to the recent reduction in warming imbalance as postulated by Dr Hansen, this site would be condemning it as a 'flawed hypothesis' and even bizarre or unhinged.
  10. SkS Responses to Pielke Sr. Questions
    Moderator: It's called a joke. I cannot believe KR was offended by that.
  11. SkS Responses to Pielke Sr. Questions
    KR, #69: The first two topics seem very closely related, and have received about 60 comments. I think the SPCA should be concerned!
    Moderator Response: [John Hartz] Your admonition registers on my Snarky Meter. Please keep it civil.
  12. SkS Responses to Pielke Sr. Questions
    Moderator(s) - While I have no desire to beat dead horses, the repeated urging to move to the next topic after less than a full exchange (i.e., at least one back-and-forth) on previous topics is rather counterproductive.
    Moderator Response: [John Hartz] While I understand your frustration, we need to "keep those doggies moving" before winter sets in.
  13. SkS Responses to Pielke Sr. Questions
    Just to let everyone know, especially Dr. Pielke, as he has become interested in SkS's outreach attempts (which is a good thing), SkS has several posts within the last few months that discuss reaching out to those with differing viewpoints for policy ideas. I cover Scott Denning's Heartland talk I introduce free market ideas for Libertarians scaddenp's GHG emission mitigation solutions - a challenge for the Right? I also discuss climate ethics that I believe can be a bridge between the political divide As far as your son's "Climate Fix", while I can't personally endorse that this will solve the overwhelming problem we face, there are certainly ideas in there that we can all agree on. SkS, as far as I know, is not against any particular policy, just agrees with the science institutions asking for legislation that will fulfill the needed purpose of assisting us through the coming global challenge.
    Moderator Response: [John Hartz] Let's move the discussion forward to the next topic, i.e., the metrics for measuring climate change.
  14. SkS Responses to Pielke Sr. Questions
    Jonathan @63, Your comment certainly highlights why we should make every effort to maturely address the science that informs us on the contemporary, short and longer term magnitude of the climate response to enhanced greenhouse forcing. We already have some good insight into both the magnitude and timescales. This issue (hard-headed and mature assessment of the science) is one of the sub-texts of this thread. Dr. Denning, in the video linked to several times here makes a forceful statement on this exact point. Incidentally, I should point out that I came across Dr. Denning's lecture while perusing Bart Verheggen's excellent blog, and so owe him a hat tip!
  15. Hyperactive Hydrologist at 22:17 PM on 21 September 2011
    SkS Responses to Pielke Sr. Questions
    Regional weather patterns are driven by global atmospheric and ocean circulation. I don't quite follow how regional land use changes can have an impact on globally driven weather. The only exception to this, that I can think of, is convective rainfall on the local scale. Perhaps someone can enlighten me on this subject. Of course from the emission point of view land use change from agriculture and forestry accounts for 30% of GHG emission. Increasing emissions from these sector has a significant impact on atmospheric GHG forcing. With increasing global population and demand for food it is very likely that emission will continue to rise. Better management is required to meet global demands while preserving existing forestry.
  16. Dikran Marsupial at 22:16 PM on 21 September 2011
    SkS Responses to Pielke Sr. Questions
    Jonathon The flaw in your argument is that current emissions may be causing a small amount of climate change in the short term, but committing us to large scale climate change on longer timescales. In that case waiting and adapting may be much more costly (or impossible) than mitigation now. This is a real concern, hence climatologists interest in equilibrium as well as transient climate sensitivity.
  17. SkS Responses to Pielke Sr. Questions
    Dr Pielke @50, consider the following hypothesis:
    "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 global climate constitutes the primary climate issue for the coming decades."
    Although it is an amended version of your (amended) 2b as presented in your post @32, the shift from a regional to a global focus is fundamentally important. By making that shift it states a hypothesis which I suspect most SkS commentators will agree with, but which you clearly disagree with. In contrast, I (at least) believe that whether purely regional forcings or global forcings are most significant to changes in climate in a particular region at present depends strongly on the region in question. The recent, and unusual aridity of South West Western Australia, for example, is almost certainly due to changes in the Hadley Cell brought about by global warming. I have no doubt that you can point out regions in which the regional forcing is clearly more significant. But I have no doubt that by 2100 the climate response will be dominated by global forcings at all scales. You attempt to rebut this perspective in responding to KR @49, but frankly I am not buying it. I live in a state whose weather is dominated by wind patterns in the central Pacific, thousands of kilometers away, wind patterns I have never personally experienced. It is true that the rain that fall on my head falls only in Brisbane, and the wind that blows in my face blows only in Brisbane. To conclude from that that we can determine the strongest influence on the weather I experience by determining the strongest forcing in the immediate vicinity of Brisbane is a non-sequitor; and indeed, a complete failure to understand the distinction between weather and climate. From a different perspective, the largest seasonal influence on my quality of life is the Northern Hemisphere Winter. The increased consumption of oil for heating drives up petrol prices while I enjoy summer sun, and has a far larger direct impact on my quality of life than any regularly recurring event relating to Brisbane weather. And note that it is the NH Winter. It is not the Seattle Winter, and the Moscow Winter and the Oslo Winter, as if these are somehow separable and could occur at distinct times. If they could, they would have little or no impact on me. But they are not separable. The NH winter is an irreducibly hemispheric climactic event, and any attempt to analyse it as the sum of many regional events will completely misunderstand it.
    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.
  18. SkS Responses to Pielke Sr. Questions
    Bart, In the long run, your assertion is correct; we need to limit how much we change the environment. In the short term, the magnitude of global warming is important, because it will dictate how we should proceed with our limits. If the magnitude is great and the timeframe is short, then drastic actions need to be undertaken immediately. If the magnitude is low and the timeframe long, then we can take the time to implement the best possible adaptive measures with minimal impact on the populace.
  19. SkS Responses to Pielke Sr. Questions
    For those who prefer reading over video watching, here's a little recap of Scott Denning's talk at Heartland.
  20. SkS Responses to Pielke Sr. Questions
    Pielke Sr's reply to Q3 is worth noting, as it highlights that people can agree on the broad question of what needs to be done, while disagreeing about details of the scientific picture. Quoting Herman Daly: "if you jump out of an airplane you need a crude parachute more than an accurate altimeter." "3. Do you agree that continuing on our current business-as-usual emissions path presents an unacceptable (in your opinion) risk to the biosphere and to human society in general within the next century? Pielke Sr: Of course. The emission of CO2 into the atmosphere, and its continued accumulation in the atmosphere is changing the climate. We do not need to agree on the magnitude of its global average radiative forcing to see a need to limit this accumulation. The biogeochemical effect of added CO2 by itself is a concern as we do not know its consequences. At the very least, ecosystem function will change resulting in biodiversity changes as different species react differently to higher CO2. The prudent path, therefore, is to limit how much we change our atmosphere. By continuing to argue on global warming and its magnitude, I feel you, and others, are missing an opportunity to build up a larger consensus on how to properly deal with the myraid ways we are altering the climate and the environment, in general. Even if there were no global warming (or even cooling) in the coming decades, we still need to limit how much we change the environment (including land use change, nitogren deposition, CO2 etc)."
  21. SkS Responses to Pielke Sr. Questions
    Dr. Pielke, I don't see the need to restrict attention to ONE focus. Surely we can walk and chew gum at the same time?
  22. SkS Responses to Pielke Sr. Questions
    Incidentally Dr. Pielke (re @ 56), as you say Scott Denning did indeed engage with the so-called "skeptics" at the Heartland Institute. He lambasted them for their nit-picking and obfuscation of the science, exhorted them to start taking the isues seriously, and questioned whether their unwillingness to engage maturely with these issues might be because they are "cowards"! He did this in an engaging and admirable manner but his point was deadly seriously. Would that everyone involved with obfuscation and prevarication on issues of profound importance would take his sentiments to heart.
  23. SkS Responses to Pielke Sr. Questions
    Dr Pielke, your conclusion:
    "Regardless, however, it is the changes in regional and local climate statistics that matter and that is where our focus should be."
    seems to be relevant to adaptation policy but is not helpful in consideration of mitigation policies, unless you mean that it is the local scale consequences that should impel us to address mitigation at the global scale (which I guess is a pretty obvious point, but maybe you could confirm that you agree with this). For example if our best understanding on warming-induced precipition regime changes to global warming indicates progressive latitudinal expansion and severity in the currently drought-susceptible latitude bands, then this is something that can only really be addressed by mitigation on the global scale, even if we are already committed to having to make local scale adaption policies. Once the terrestrial environment stops being a net sink for anthropogenic greenhouse gases, these considerations will become ever more pressing. The same could be said for sea level rise. Efforts at mitigation requre global scale consideration. Impacts and adaptation will occur on the local scale [The Dutch Delta Commision on sea level rise is taking local implications of 21st sea level rise on the 1 metre plus scale very seriously, whereas presumably the inhabitants of North India have little concern about 21st century sea level rise, but do have concerns about warming induced attentuation of mountain glacier sources of water supplies and so on.] So we're stuck with adaptation at the local scale. The extent to which these become difficult and then possibly unacceptable burdens on our resources depends on our willingness to make the difficult decisions at mitigation on the global scale I'm glad that you (Dr. Pielke) respect the views of Dr. Denning and hope that you agree with the sentiments he presented in his recent short talk where he highlights both the reality of the issues and a mature approach to addressing them. He clearly consders that consideration of greenhouse gas forcing on the global scale is the issue that needs to be addressed.
  24. Dikran Marsupial at 21:11 PM on 21 September 2011
    SkS Responses to Pielke Sr. Questions
    Prof. Pielke Perhaps I wasn't sufficiently clear, I was not asking for your views on tropical temperature trends. I was asking for your view on that specific paper by Douglass et al., which as I pointed out contains a very severe statistical error that fundamentally undermines the conclusion drawn. I note that the paper you reference cites the Douglass et al paper as "pointing to the potential for fundamental problems with the models", however it hardly provides support for such a contention as the methodology used did not show that the observations were inconsistent with the models as claimed. Do you think the method used by Douglass et al. is statistically sound? A direct answer would be greatly appreciated. By the way, on page 2161, Christy et al. (2010) says "This implies there is a 3% chance that the trend is non-positive in a statistical sense". This appears to be a clear example of the p-value fallacy. A 3% probability of observing a trend at least as great assuming the null hypothesis is true is not the same as there being a three percent probability that the null hypothesis is true. N.B. I will happily discuss Christy et al. (2010) (which appears to also have statistical errors) with you after you have answered my question regading the Doulgass et al. paper.
  25. 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.
  26. 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.
  27. 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
  28. 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.
  29. 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."
  30. 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. :-)
  31. 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.
  32. 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.
  33. 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.
  34. 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.
  35. 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.
  36. 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.
  37. 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.
  38. 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?
  39. 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.
  40. 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 …
  41. 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.
  42. 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.
  43. 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.
  44. 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.
  45. 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."
  46. 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.
  47. 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.
  48. 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.
  49. 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.
  50. SkS Responses to Pielke Sr. Questions
    I propose we declare the topics of anonymity and harassment as "off topic."

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