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Comments 74351 to 74400:

  1. SkS Responses to Pielke Sr. Questions
    I propose we declare the topics of anonymity and harassment as "off topic."
  2. 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.
  3. 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.
  4. 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.
  5. 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.
  6. 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?
  7. SkS Responses to Pielke Sr. Questions
    Dana Nuccitelli - Thanks for clarifying.
  8. 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.
  9. 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.
  10. 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.
  11. 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.
  12. 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.
  13. 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.
  14. 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?
  15. 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?
  16. 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.
  17. 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.
  18. 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.
  19. 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.
  20. 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].
  21. 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...
  22. 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.
  23. 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.
  24. 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.
  25. 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.)
  26. CERN - Saying Nothing About Cosmic Ray Effects on Climate
    I certainly agree that today's CO2 surplus comes from fossil fuel burning but I was referring to Veizer's finding. Kuo's paper explains the pre fossil variations nicely: http://www.nature.com/nature/journal/v343/n6260/abs/343709a0.html GCRs don't need to be decreasing to cause warming. Remaining at a constant low level reduces cloud cover causing a gradual rise in temperature which is cumulative. They are rising again and if the cloud theory is right we will see cold cloudy weather for decades. Time will tell which theory is right. The current la nina seems to be coming back so we may not have to wait long to find out who is right.
  27. SkS Responses to Pielke Sr. Questions
    To avoid confusion, I wonder if we can all focus on one question/response at a time. Maybe topic 1 would be a rational place to start? Discuss that until there's no more juice; and then move to the next?
  28. SkS Responses to Pielke Sr. Questions
    Dr Pielke @11, the two hypotheses presented by you for your first question may be intended to be contraries, but in fact they are not. The are:
    "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). 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."
    I have bolded the differences between the two hypotheses. You should note that: a) 2a only refers to CO2 explicitly, which means that for the purposes of 2a other GHG such as CH4 and NO2 are distinct "first order climate forcings". In contrast, in 2b CO2 is grouped with all other GHG and declared to be dominant. Consistent with that, the sum of all GHG forcings in 2a could be dominant even though CO2 by itself is not. b) 2a makes no declaration as to whether CO2 (or all GHG) represent a dominant forcing or not. As such it does not contradict the claim that the sum of all GHG is dominant, it merely asserts that there are other significant forcings, and hence does not contradict 2b. c) The term "dominant" in 2b is vague, and may indicate any of the following: - That the GHG forcing is greater than any other individual forcing; - That the GHG forcing is greater than the sum of all other individual forcings; - That the GHG forcing is much greater than the sum of all other forcings; or - 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. The first two of these alternatives are certainly consistent with the spirit of 2a, and only the last contradicts the spirit (though not the letter) of 2a. Consequently, if you intend that the two hypotheses be contraries, you need to tighten up your language substantially. 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: I note in passing that the two hypotheses from Mike Hulme are also not contraries, whatever his, or your intentions, and fail to be contraries for very similar reasons to those above.
  29. SkS Responses to Pielke Sr. Questions
    Radiative forcing from IPCC AR4 Might want to also consider Carbon dioxide emissions and their associated warming could linger for millennia Given that IPCC projections tend to focus most closely on the next 100 years, seems they aren't grasping the full long-term impacts of CO2 emissions. At any rate, I don't see how anyone could state the IPCC is at odds with Hypothesis 2a, but Dr. Pielke is free to make his case.
  30. CERN - Saying Nothing About Cosmic Ray Effects on Climate
    tblakeslee - "When the oceans are warm CO2 comes out of solution but it is an effect not a cause as shown by the time delay." I strongly suggest you read the CO2 is coming from the ocean thread, as that is an incorrect statement as proven by isotopic analysis and the acidification of the oceans. And you have still not addressed the fact that GCR's do not correspond to the temperature changes of the last 50 years. That GCR hypothesis does not match the facts, and when that happens, it's time for a new hypothesis.
  31. SkS Responses to Pielke Sr. Questions
    Dr. Pielke About your suggestion that SkS speak to Mike Hulme directly, I would point out that Hulme developed six ways of framing the phenomenon of climate change. He said this about those framings: "These six frames around climate change all attract powerful audiences, interests and actors in their support. All of them – with the exception of climate change as mostly natural – would be broadly consistent with the scientific knowledge assessed by the Intergovernmental Panel on Climate Change." Source: "You’ve been framed: six new ways to understand climate change," by Mike Hulme, The Conversation, July 5, 2011. To access this post, click here To the best of your knowledge, has Hulme changed his mind since the posting of his paper?
  32. CERN - Saying Nothing About Cosmic Ray Effects on Climate
    The orbital momentum is an an important part of the forecasting. Quting from the paper I referenced (under the diagram plotting the center of mass: "The large solid circle marks the sun's surface. Most of the time, the CM is to be found outside of the sun's body. Wide oscillations with distances up to 2.2 solar radii between the two centres are followed by narrow orbits which may result in close encounters of the centres as in 1951 and 1990. The contribution of the sun's orbital angular momentum to its total angular momentum is not negligible. It can reach 25 percent of the spin momentum. The orbital angular momentum varies from -0.1·1047 to 4.3· 1047 g cm2 s-1, or reversely, which is more than a forty-fold increase or decrease (Landscheidt, 1988). Thus it is conceivable that these variations are related to varying phenomena in the sun's activity, especially if it is considered that the sun's angular momentum plays an important role in the dynamo theory of the sun's magnetic activity." Here is a newer paper that has more details: http://arxiv.org/ftp/arxiv/papers/1005/1005.5303.pdf The sun is like a dynamo that makes magnetic fields which block GCRs. Luminoscity is a minor factor. Its about magnetic fields. Here is a 2006 interview with Veizer where he still is defending the solar connection. When the oceans are warm CO2 comes out of solution but it is an effect not a cause as shown by the time delay.
  33. Debunking Climate Myths from Politicians
    gavin, First off, it a fallacy that you need tropical forests to produce oil. Oil source rocks come from a variety of sources. Type I and II (especially) kerogens are best oil producers, and originate from plankton and spores. Marine black shales are examples. I work at opposite end of planet and I am unfamiliar with arctic source rock but I believe Mesozoic black shales are common. Land sources (forest/peat) form type III kerogens and are gas-prone. They are minor players in the oil world. And yes, plate tectonics matter. Need to look at where arctic was when source rock was formed. No ice caps in mesozoic though so productive ocean enough to produce the required source rock even if it was in on the pole. Its a debatable question as to whether a warmer climate is better or not. What isnt debatable is that rapid climate change in either direction is bad. Our civilization and agriculture is deeply dependent on current sealevel and climate and changing it quickly would be expensive in many ways.
  34. SkS Responses to Pielke Sr. Questions
    My response and answer to your questions might be clearer in my weblog post on this but I have entered it here too. Dr. Pielke's questions are underlined in the text below, and the answers from SkS follow. 1. Of the two hypotheses below, which one do you conclude is correct? (see Dr. Pielke's post for the two hypotheses offered) The two aren't mutually exclusive, and both are correct. CO2 is the dominant radiative forcing causing the current global energy imbalance. R.Pielke Sr. Response - First, let me thank you for moving on to actual science issues. In response to your first answer, they actually are separate hypotheses and only one of them can be correct. We discuss this in 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. http://pielkeclimatesci.wordpress.com/files/2009/12/r-354.pdf where we wrote "Hypotheses 2a and 2b are two different oppositional views to hypothesis 1. Hypotheses 2a and 2b both agree that human impacts on climate variations and changes are significant. They differ, however, with respect to which human climate forcings are important.......... we suggest that the evidence in the peer- reviewed literature (e.g., as summarized by National Research Council (NRC) [2005]) is predominantly in support of hypothesis 2a, in that a diverse range of first-order human climate forcings have been identified." "We therefore conclude that hypothesis 2a is better supported than hypothesis 2b, which is a policy that focuses on modulating carbon emissions. Hypothesis 2b as a framework to mitigate climate change will neglect the diversity of other, important first- order human climate forcings that also can have adverse effects on the climate system. We urge that these other climate forcings should also be considered with respect to mitigation and adaptation policies." and "The evidence predominantly suggests that humans are significantly altering the global environment, and thus climate, in a variety of diverse ways beyond the effects of human emissions of greenhouse gases, including CO2. Unfortunately, the 2007 Intergovernmental Panel on Climate Change (IPCC) assessment did not sufficiently acknowledge the importance of these other human climate forcings in altering regional and global climate and their effects on predictability at the regional scale. It also placed too much emphasis on average global forcing from a limited set of human climate forcings. 2. Of the two perspectives below [from Mike Hulme], which one do you agree with? (see Dr. Pielke's post for the two perspectives offered) Again, the two perspectives are not mutally exclusive, and both are correct. As Hulme notes, they are simply two different framings. In terms of climate policy, the second framing is probably more appropriate, as addressing climate change will involve more than just CO2 emissions reductions. R.Pielke Sr. Response - If the second framing is more appropriate, we have made progress towards agreement as that framework fits with hypothesis 2a. I also suggest you contact Mike Hulem for his view whether both perspectives can be "correct". 3. What is your preferred diagnostic to monitor global warming? SkS doesn't have a preferred diagnostic - all lines of evidence must be taken into account. It's important to look at all the data in totality to monitor global warming (surface temperature, ocean heat content, atmospheric temperature, TOA energy imbalance, sea level rise, receding ice, etc.). R.Pielke Sr. Response - Global warming or cooling involves changes in Joules of heat in the climate system. This involves changes in heat in the oceans, land, atmosphere and cryosphere. As concluded by Jim Hansen and others, the ocean is by far the component of the climate system where the large majority of this heating and cooling occurs. Receding ice, surface temperature, atmospheric temperatures make up only a relatively small portion of global warming and cooling. What is your best estimate of the observed trends in each of these metrics over the last 10 years and the last 20 years? 10-year trends are generally not statistically significant (see Santer et al. 2011, for example). The approximate best estimate observed trends for some of these metrics over the last ~20 years are as follows. TLT: 0.18°C per decade. Surface temperature: 0.18°C per decade. Ocean Heat Content (OHC) upper 700 meters: 6.3 x 1022 J per decade. Sea level rise: 32 mm per decade. Arctic sea ice volume: -2900 km3 per decade. Glacier mass balance: -180 mm w.e. per decade. 4. What do the models’ predict should be the current value of these metrics? The surface temperature change is roughly consistent with model predictions, though perhaps a bit on the low end. The predicted TLT trend is approximately 0.26°C per decade. Sea levels are rising faster and Arctic sea ice is declining far faster than models predict. OHC in the upper 700 meters increased more than the models expected from 1961 to 1999, and has increased less than models project since 2003. There are a number of factors that may explain the recent discrepancy: as noted above, this is too short of a timeframe for a valid statistical evaluation; models generally do not take the increases in aerosol emissions over this period into account; there is a wide range of estimates of upper 700 meter OHC trend since 2003, varying by nearly two orders of magnitude; and the oceans are much deeper than 700 meters, and the so-called "missing heat" may very well reside in the deeper oceans (i.e. see Meehl et al. 2011). We have discussed this subject previously here and more recently here, taking the deep ocean into account. One reason that we like to rely on multiple lines of evidence, rather than depend on one single indicator, is that any one can be wrong. The history of the UAH measurements comes to mind: the measurements were in conflict with other methods for tracking temperature change (and with climate model projections) for over a decade; eventually, most of the discrepancy was resolved (in favor of the models) only after very subtle analysis of the physical behavior of the instruments. R.Pielke Sr. Response - The oceanographers who work with the ocean heat data are convincing (at least to me and a number of other colleagues) that since the completion of the Argo network, it is a robust metric (within defined uncertainty bars) such as Josh Willis placed on the figure he provided me for the article Pielke Sr., R.A., 2008: A broader view of the role of humans in the climate system. Physics Today, 61, Vol. 11, 54-55. http://pielkeclimatesci.wordpress.com/files/2009/10/r-334.pdf 5. What are your preferred diagnostics to monitor climate change? That depends on how "climate change" is defined, but again, it is necessary to look at all lines of evidence and data. R.Pielke Sr. Response - You avoided answering this question. This is actually an essential issue to resolve. The NRC (2005) report [http://www.nap.edu/openbook.php?record_id=11175&page=200] defines climate change as "The system consisting of the atmosphere, hydrosphere, lithosphere, and biosphere, determining the Earth’s climate as the result of mutual interactions and responses to external influences (forcing). Physical, chemical, and biological processes are involved in interactions among the components of the climate system. " This is much broader than just global warming and cooling. Please clarify your view. 6. Is global warming (and cooling) a subset of climate change or does it dominate climate change? Again, that depends on how "climate change" is defined. Long-term global temperature and climate changes are both ultimately caused by global energy imbalances. R.Pielke Sr. Response - The recognition that climate changes can occur without any global energy imbalance is central to the much needed broader view of how humans are altering the climate system. Please clarify what is "climate change" in your view. Now that we have answered your questions, there are a few issues on which we would like to understand your perspective, Dr. Pielke. SkS Questions for Dr. Pielke 1. Approximately what percentage of the global warming (increase in surface, atmosphere, ocean temperatures, etc.) over the past 100 years would you estimate is due to human greenhouse gas emissions and other anthropogenic effects? And the past 50 years? This is a good question. It is a still incompletely understood mix of a variety of human caused radiative forcings (e.g. CO2, methane and several other greenhouse gases, land use/land cover change, black carbon (soot), sulphates, and other aerosols) and natual climate variations. Several years ago I did a back of the envelope estimate and came up that ~26% of the positive radiative forcing was from CO2; see slide 12 in Pielke, R.A. Sr., 2006: Regional and Global Climate Forcings. Presented at the Conference on the Earth’s Radiative Energy Budget Related to SORCE, San Juan Islands, Washington, September 20-22, 2006. http://pielkeclimatesci.wordpress.com/files/2009/09/ppt-69.pdf. This number certainly changes through the last 100 and the last 50 years, and remains uncertain. The complexity of these radiative forcings is discussed in some detail in NRC (2005) - http://www.nap.edu/openbook/0309095069/html/. Despite the vigor with which you criticize Roy Spencer, he actually has been instrumental in elevating our awareness that natural variations in cloud cover, as a result of temporal variations in atmospheric circulation features, as causing long term variations in the TOA radiative imbalance. 2. Do you find Spencer, Lindzen, and Christy's arguments that equilibrium climate sensitivity is in the ballpark of 1°C or less for doubled atmospheric CO2 plausible? If so, how do you reconcile this low climate sensitivity with the paleoclimate record, for example needing to explain ~5°C swings in average global surface temperature between glacial and interglacial periods (i.e. see the figure below from Hansen and Sato 2011)? I do not find the glacial and interglacial periods as useful comparisons with the current climate since when we study them with models, they have large differences in imposed terrain (e.g. massive continetal glaciers over the northern hemisphere which will alter jet stream features, for example). In any case, I find the discussion of the so-called "climate sensitivity" by all sides of this issue as an almost meaningless activity. I posted on this in So-Called “Climate-Sensitivity” – A Dance On The Head Of A Pin - http://pielkeclimatesci.wordpress.com/2011/09/09/so-called-climate-sensitivity-a-dance-on-the-head-of-a-pin/ 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? 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). 4. Do you agree that continuing on our current business-as-usual emissions path presents an unacceptable (in your opinion) risk to marine ecosystems in the form of ocean acidification within the next century? Regardless of whether we reduce the alkalinity of the oceans (since there may be buffering from the added CO2 through mixing from below) we will be altering ecosystem function both in the oceans and in the atmosphere. Since we do not know the consequences of doing this, the smart thing to do is to work towards reducing the extent we alter the chemisty of the oceans and the atmosphere. 5. Do you think that we should begin to move towards a low-carbon economy, thereby reducing anthropogenic GHG emissions? I am very much in favor of energy sources which minimize the input off gases and aerosols into the atmosphere. Much of my career has been involved with reducing air pollution (both in research and in policy). What we should move towards is an economy with as small a footprint on the natural environment as possible. In terms of how to do this with respect to carbon emissions, I completely agree with my son's perspective as he presents in The Climate Fix - http://theclimatefix.com/
    Moderator Response: [John Hartz] Thank you for your prompt response. To make it easier for everyone to follow your response, would it be OK if we were to bold face your set of questions to SkS and the set of SkS questions to you?
  35. Are you a genuine skeptic or a climate denier?
    Dana69 - You seem to be overlooking my statement here, "...the world isn't 33C warmer than it would be without greenhouse gases?" The atmosphere with greenhouse gases causes the climate to be about 33°C warmer than it would be without those gases. Therefore your antecedent "if the atmosphere doesn't drive climate", and hence your syllogism, are quite false. See even a basic writeup of the Greehnouse Effect for some details. Please - read some of the science. Your repeated contradiction of basic physics is either ignorance of said science or, quite frankly, just making stuff up to object - denial.
  36. Trenberth, Fasullo, and Abraham Respond to Spencer and Braswell
    @Stig "I think commenter Bart Verheggen was quick to point out that Watts has misunderstood the paper, and none other than Roy Spencer confirmed it." It's doubtful that the readership at WUWT would even ask themselves the question, that if WUWT is misrepresenting someone batting for their own team. Then how much are they misrepresenting someone from the opposing team? When will Spencer & Braswell raise their standards bar a little & aim to publish in journals of higher repute?
  37. SkS Responses to Pielke Sr. Questions
    Currently, on Bishop Hill Blog, SS is being accused of rewriting history in the good old Stalinist way. http://bishophill.squarespace.com/blog/2011/9/20/cooking-the-books.html#comments Would one of the mods care to comment?
    Response: [John Hartz] The Bishop Hill post is being reviewed by the SkS author team as we speak.

    [John Cook] I've posted a response in the Bishop Hill comments thread.
  38. Are you a genuine skeptic or a climate denier?
    480, 482, Dana69,
    The atmosphere does not drive climate.
    Patently false and evidence of denial.
    It can have some affect, but the amount and extent is a large variable up for discussion.
    Patently false and evidence of denial. Do you have anything to say other than "I don't believe in science?"
  39. Debunking Climate Myths from Politicians
    Hi scaddenp, The guy making the comment was a skeptic. I'm studying carbon management and as part of an assignment I had to ask him what he thought about offsets. That set him off in a 'friendly' tirade. So given that you mention plate tectonics, I assume you are suggesting that the fossil fuels were created from fossils which were originally from warmer areas and moved underground? And if the earth was warmer than now, is the common response that it wasn't so harmful as humans weren't around yet? Thanks.
  40. SkS Responses to Pielke Sr. Questions
    I will note that the recent increase in 'skeptic' blogs attacking SkS is actually a compliment - Bishop Hill, Pielke, Watts, JoNova, etc., are taking the information here seriously enough to denigrate it. That said, I would encourage moderation in the rhetoric in return. When someone without an axe to grind comes upon a discussion, the person ranting is likely to be dismissed. I will always treasure the episode on JoNova's blog where one of the regular skeptics was told by the site moderators to tone things down, as his accusations of 'liar!!!' were making me look good. Let's take the high road, eh?
  41. SkS Responses to Pielke Sr. Questions
    John (Hartz) my post (and this may be true of some of the others) is (a) a highlight of what I imagine many posters would find very useful and relevant, and (b) refers to Drs Pielke in reference to the general policies of these individuals. I do agree with your sentiment, but in that case it might have been better to put an embargo on comments on this thread until Dr Pielke responded. If you open a thread for comments you can't not expect to receive them...!
    Moderator Response: [John Hartz] Because I am a relative newcomer to the ranks of SkS Moderators, I have yet to delete anyone's posts on a comment thread. I would, however, point out that you began your post with "This is slightly off topic..." Otherwise, your points are well taken.
  42. Are you a genuine skeptic or a climate denier?
    KR, Does the whole argument rest on "product of the atmosphere"? I misspoke, I meant to say CO2 is part of the atmosphere, and if the atmosphere doesn't drive climate, then CO2 doesn't drive climate. That is a basic syllogism.
  43. Are you a genuine skeptic or a climate denier?
    Dana69 - "The atmosphere does not drive climate. CO2 is a product of the atmosphere." Really - such amazing statements... So the 29-30 billion tons of CO2 from our yearly emissions are a 'product of the atmosphere'? And the world isn't 33C warmer than it would be without greenhouse gases? As I said, denial. Until and unless you actually read up on the science, I don't think it's worthwhile discussing matters with you. I would suggest The Carbon Dioxide Greenhouse Effect as a starting point. As to the uncertainties in various values - they exist. But, you appear to be certain that the numbers are zero, when all evidence points to non-zero ranges. So based on some uncertainty you are claiming values outside any range supported by evidence. That's not rational at all, and in fact is a logical fallacy.
  44. CERN - Saying Nothing About Cosmic Ray Effects on Climate
    tblakeslee#71: "orbital momentum of the sun undergoes a forty to one increase" 'Orbital momentum'? Do you mean 'angular momentum'? And how does a change in momentum of any kind have anything to do with cosmic rays? "As Shaviv showed, GCRs can account for very large changes in climate" Shaviv 2005 shows this: the CRF/climate link therefore implies that the increased solar luminosity and reduced CRF over the previous century should have contributed a warming of 0.47 ± 0.19°K, while the rest should be mainly attributed to anthropogenic causes. That's if there is a CRF/climate link, a point that has not yet progressed beyond mere hints.
  45. CERN - Saying Nothing About Cosmic Ray Effects on Climate
    tblakeslee, Shaviv showed nothing of the sort. Shaviv (and Veizer) made a tentative hypothesis that the passage of the Earth through the spiral arms of the galaxy might modulate the cosmic ray flux on 100's of million year time scale with a broad cyclic effect on Earth temperature. There is no evidence that this hypothesis has merit, and Shaviv's coauthor Jan Veizer, reassessed his temperature reconstruction and concluded that the temperature variation through a major part of Earth history doesn't actually correlate at with the putative CRF effect at all. In fact Veizer concluded that the major determinant of Earth temperature in the deep past is atmospheric [CO2]: R.E. Carne, J.M. Eiler, J. Veizer et al (2007) Coupling of surface temperatures and atmospheric CO2 concentrations during the Palaeozoic era; Nature 449, 198-202
  46. Are you a genuine skeptic or a climate denier?
    KR, We both come to conclusions in different ways. If you are comfortable with the level of uncertainty, and are willing to act using the precautionary principle, so be it, but that does not in of itself validate the argument. The atmosphere does not drive climate. CO2 is a product of the atmosphere. It can have some affect, but the amount and extent is a large variable up for discussion. Try to quantify that.
  47. Are you a genuine skeptic or a climate denier?
    Ugh - KR - you beat me to it. Forget leaving the house--simple thought, having been rendered functionless, would be almost impossible.
  48. SkS Responses to Pielke Sr. Questions
    In my opinion, the first five posts should be withdrawn or deleted because Dr. Pielke has not yet responded to Dana's article. It's rather cheeky to assume that one knows in advance what Dr. Pielke's response will be.
  49. CERN - Saying Nothing About Cosmic Ray Effects on Climate
    The paper is a bit old because Landscheidt died in 2003. He did publish in refereed journals such as Solar Physics and Climatic Change. The Journal of Coastal Research Special Issue No. 17 (1995), p 371-382 included the paper I referenced. The orbital momentum of the sun undergoes a forty to one increase and decrease due to the various planets orbital relationships. As Shaviv showed, GCRs can account for very large changes in climate including the very large swings from ice age to warm periods. Hardly a "minor effect." Here is another paper that shows that relationship and also discusses the accurate predictions of La Nina and El Nino periods based on planetary gravitational effects on the sun. http://www.john-daly.com/sun-enso/revisit.htm Most of the distressing weather this year including the famine in Somalia, floods in Australia and the US midwest were caused by the same La Nina that Landscheidt predicted using sound science a decade ago. Thanks for the good comments but I really feel that a theory is only as good as its ability to predict and I remain very impressed with the solar/cloud connection.
  50. SkS Responses to Pielke Sr. Questions
    Looks like many of the questions were designed for entrapment. I'm amazed there wasn't "do you still beat your wife?"
    Moderator Response:

    [John Hartz] Which set of questions are you referring to?

    [Daniel Bailey] Inflammatory struck out.

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