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Comments 70151 to 70200:

  1. Cardinal Pell needs to practise what he preaches on climate change
    Mankind's Power to Create and Destroy The title and opening remarks in Cardinal Pell’s speech encapsulate all that is deficient in his worldview. His reference to the Biblical story of the Tower of Babel indicates that, to him, the idea that mankind can change the climate of the Earth is as prideful and far-fetched as the tower builder’s belief they could reach heaven. This idea is profoundly wrong both in terms of the science and theology. As to the science, John has answered that well. As to the theology, Genesis chapter 1 states that man was made "in the image of God", and was given authority to rule (responsibly) over the Earth. This means that man, like God, has the power to create and destroy. Should Cardinal Pell doubt our ability to wreck the environment, we need to look no further than our power to split the atom in the bombs dropped on Hiroshima and Nagasaki. We came perilously close to nuclear Armageddon during the Cuban missile crisis of 1963. I believe by the grace of God, we were saved at that time by President Kennedy, who unlike Cardinal Pell, understood the destructive potential of mankind’s follies.
  2. There's no tropospheric hot spot
    #10 Mango, you like taking the emotive line, but I am after a scientific reasoning as to why you believe that the tropospheric hotspot is specifically an AGW signature. The 'advanced' tab clearly shows that it is by no means unique to AGW, so where do you think this is wrong, and upon what scientific basis? You have, elsewhere, insinuated that data has then been massaged to fit the models (much like Lindzen suggested as discussed above), yet clearly this is not the case. This area of the science is one that has significant uncertainties (as the Thorne graph above shows), yet is not fundamental to the validity of our understanding of the climate system. Lindzen, Monckton and others love to portray otherwise, and I'd hate to see you be taken in by their misinformation. Forget the emotion, or feeling hurt that you've been called out on these statements you've made, as you now have a great chance to present the science for your case.
  3. Stratospheric Cooling and Tropospheric Warming - Revised
    Hi Mango @115, "appears to be really worried about why I am here" "or do you not want to engage in civilised conversation" Now you are arguing strawmen, and are also being paranoid. You still have not specified exactly which statements you have made that people are alleging are wrong. instead you now say Posters at the BBC blog are always telling me I'm wrong about everything". Regardless, I and others here, are happy to engage in a cvil scientific discussion with you. What are say your three primary issues/positions that you have, that you have been told are wrong, and which you believe refute or call into question the theory of AGW? We can then address them on the relevant thread. I was under the impression, going by your very first comments on another thread, that they had something to do with temperature trends in the stratosphere no? Specifically, you seem to think that because the stratosphere has not cooled recently that this is a significant flaw in the theory (no quotation remarks required) of AGW. Let us look at the big picture shall we, instead of cherry picked short-term trends that have no statistical significance and which, as such, cannot be used to accept or reject the null hypothesis. [Source]
  4. Extreme Events Increase With Global Warming
    How about also considering that the effects of blocking patterns are more severe in a warmer world? (ie both more severe drought - higher evaporation rate, and more severe flooding - rain intensities are jigher so a prolonged pattern has greater effect).
  5. Medieval Warm Period was warmer
    I've read the Mann et al 2009 paper linked above and I've a question. The authors compare the overall pattern of change between Medieval Climate Anomaly and Little Ice Age, as reconstructed from proxies and simulated by models. And they conclude : « The observed patterns of change, even when averaged over multicentury intervals, are unlikely to be entirely forced in nature, as there is also a potentially important role for purely internal, natural variability. » Reference to the unforced natural variability is unclear for me. I have often read that such an intrinsic variability cannot create any long term trend. This is a typical Tamino argument : energy is redistributed, not created, by (unforced) natural variability so you do not expect from it any decadal-to-century trend in surface temperature, just a season-to-year signal, up-and-down noise. So, what are Mann et al alluding to when they mention such a « purely internal » variability which could explain part of the averaged multicentury pattern ?
  6. Tar Sands Impact on Climate Change
    “Conventional wisdom has it that the next election will be fought exclusively on the topic of jobs. But President Obama’s announcement last week that he would postpone a decision on the Keystone XL pipeline until after the 2012 election, which may effectively kill the project, makes it clear that other issues will weigh in -- and that, oddly enough, one of them might even be climate change.” Source: “Bill McKibben, Puncturing the Pipeline” TomGram, Nov 15, 2011 To access this insightful analysis, click here.
  7. Stratospheric Cooling and Tropospheric Warming - Revised
    I'll read through the comments and get back to you, (-snip-) OK, albatross, you read the comments, seemingly everywhere! Posters at the BBC blog are always telling me I'm wrong about everything and they tell me all the answers lie at SkS. I do read the links, even though I suspect the posters at the BBV never read the links from the opposing camp And that's why I'm here - to engage in conversation. I'm not saying you will convince me, I really think the AGW "theory" is flawed, but I'm open to being convinced and I have, on several occasions at the BBC and WUWT, stated that we shouldn't read too much into papers that, for example, show lower climate sensitivity than the IPCC would have us believe, because the papers are still based on models not on empirical data (-snip-)
    Response:

    [DB] Welcome to Skeptical Science.  Here we focus on the science, not on rhetoric or ideology; that focus immediately separates SkS from the other sites you reference. Please familiarize yourself with the Comments Policy of this site.  Note that a continued focus on "camps" or "tribes" detracts from one's credibility here.

    Inflammatory snipped.

  8. Stratospheric Cooling and Tropospheric Warming - Revised
    Mango @109, "AGW hypothesis" Actually, it is the theory of AGW. There is a significant/important difference between a "hypothesis" and a "theory".
  9. Stratospheric Cooling and Tropospheric Warming - Revised
    Mango, You see this is exactly why I asked my questions @10. I do not recall questioning why you are here. I am glad to here that you are willing to listen to the evidence, but we shall see. Now in order to help you and to focus the discussion I repeat, specifically, what statements have you made that "they" have told you were wrong. You made reference to that in your post @100 when you said: "People tell me i am wrong and point to SkS, so i thought i would ask here" Someone in the interim has replied to one of your other questions that asked after reading a post, but I am more interested in what you have been saying that people claim is wrong, the alleged real reason for you being here. Can we please help you address that?
  10. World Energy Outlook 2011: “The door to 2°C is closing”
    Philippe : I agree, my first words were imprecise. Also, I understand and share your concern, but a larger debate on market-equilibrium models failure, short-termism in economy policy and illusion of infinite exponential growth in a finite planet (Bartlett from Bernard) would probably be off-topic here. (Note that IEA as well as IPCC SRES share a basic assumption of sustained economic growth for coming decades… non compatible for example with a fast fossil depletion.) Furthermore, I also quoted the correlates of energy so as to remind a fundamental fact : whatever your economic system is (capitalist, socialist, feudal, etc.), it’s very unlikely that a low production and consumption of energy will meet the common criteria of human welfare. Bolivia, Yemen or Haiti have an ideal energy consumption per capita for climate stabilization, but few people in developped or emerging countries would consider their HDI as their new ideal. There would be no debate if we can simply give up fossil fuels without any sacrifice, or if climate stabilization was the unique problem of humanity. Look at the Millenium Development Goals of United Nations : most of them are not energy-free in their achievement and no climate objective is sustainable that would worsen on short-term the vulnerability to non-climatic hazards or threats. IEA (and Andy) message is clear : we’re committed to act for climate stabilization, and to act now. So, part of the debate should now deal with the efficiency and security of present energy alternative to fossil fuels ‘other things beeing equal’, because if we condition our climate action to the instauration of a perfect economic and political world system, we will never act ! And similarly, if we choose the worst solutions revealing their negative side-effects for other human needs or concerns, a long-term policy will be very difficult to maintain. On biofuel in their current generation, I think there are all sort of reasons to consider they may be a local and partial solution (eg Brazilian way if enviromentally constrained), but to doubt and even to fear their global extension to the detriment of agricultural use. Most studies do find an influence on crops price, so we cannot just pick those which don't so as to conclude there is no risk at all. (Thereafter, a quite devastative assessment of biofuel by International Energy Forum, including the crop price risk) http://www.ief.org/PDF%20Downloads/Bio-fuels%20Report.pdf Edmh : hem, we're discussing IEA report, 450 scenario and choices in energy policy, not exactly your topic.
  11. Stratospheric Cooling and Tropospheric Warming - Revised
    Mango, short answer... You are wrong in thinking that OLR has increased. There is a net 0.9±0.5 W/m2 imbalance... less, not more. The proper value is, I think, hard to detect reliably considering all of the noise inherent in the system and without better satellite measurements and longer time periods with which to accumulate averages (although Trenberth appears to have done so, and I'd have to look at his paper again to see how)... and sadly satellites keep failing to reach orbit and funding for them is rather dry with the Republican Party in power in the U.S. House. At the same time, however, KR's link to Is the CO2 Effect Saturated as well as this link to Have American Thinker disproven global warming? together show that while the total imbalance is difficult to detect, the expected changes in specific frequencies of OLR -- fingerprints not of any imbalance and warming, but of the effects of CO2 in particular -- are detectable and present. Your argument/question is not invalid. We simply don't have the resources to observationally support or refute the question of which substance, ozone or CO2, is more responsible for the cooling of the stratosphere. But we do have other observations that more than suffice to make us believe that answering that particular question is not all that important. No one really thinks for a minute, nor should they based on the wealth of other evidence, that CO2 is somehow not responsible for both warming the planet and cooling the stratosphere, exactly matching what is predicted by our firm understanding of the physics, but instead that ozone is cooling the stratosphere and some other mysterious, unnamed, unknown force is warming the globe, while CO2 is somehow surprisingly not behaving as all physics expects. So, you see, the proposition that ozone is responsible for cooling the stratosphere requires four huge assumptions:
    • Ozone is responsible for the cooling of the stratosphere.
    • Something else (as yet unknown) is responsible for global warming.
    • In spite of our good understanding of the physics and all other observations that support this, CO2 is somehow not warming the globe.
    • In spire of our good understanding of the physics and all other observations that support this, CO2 is somehow not cooling the stratosphere.
  12. Philippe Chantreau at 03:35 AM on 18 November 2011
    Eschenbach and McIntyre's BEST Shot at the Surface Temperature Record
    I'm going to need aspirin if I see more TLAs...
  13. Stratospheric Cooling and Tropospheric Warming - Revised
    Actually, now that I look at the UNrounded values, it seems that Trenberth IS showing the radiative imbalance; 341.3 incoming - 101.9 reflected = 238.5 OLR + 0.9 imbalance The imbalance is labelled 'Net absorbed' at the bottom middle of the diagram.
  14. Stratospheric Cooling and Tropospheric Warming - Revised
    Mango, consider Trenberth's energy flow diagram; From this we can see that: 341 W/m^2 incoming solar radiation - 102 W/M^2 reflected solar radiation = 239 W/m^2 OLR Thus, we can also use this diagram to identify some things which could change the amount of OLR. For instance, an increase in OLR could be due to increased incoming solar radiation (which goes through a semi-regular cycle of about 11 years), increased surface reflection of solar radiation (e.g. due to higher snow coverage than usual), or increased cloud cover causing more atmospheric reflection of solar radiation. Thus, if you are angling for 'any increase in OLR for any duration disproves AGW' then you are incorrect... many things can and do cause short duration increases in OLR. Indeed, over the long term greenhouse gases have no impact on OLR. Energy out MUST equal energy in - though not immediately. An increase in greenhouse gases can cause an energy imbalance (note that Trenberth's diagram only depicts balanced flows) by temporarily decreasing the OLR rate until temperature rises enough that OLR becomes balanced again.
  15. Stratospheric Cooling and Tropospheric Warming - Revised
    @Albatross Does it really matter why I'm here? As long as I am prepared to be convinced (and I am prepared), isn't that enough? @All We seem to agree that there could be 2 reasons for the cooling stratosphere, CO2 and / or ozone depletion. The answer seems to be where in the stratosphere the cooling is happening, so do we have the records to show if the cooling affects the whole of the stratosphere or just the upper stratosphere? ----- The AGW hypothesis suggests outgoing longwave radiation should decrease. I've read the post: http://www.skepticalscience.com/American-Thinker-claims-to-have-disproven-global-warming.html which, as the author of the AT article confirms in the comments, shows that OLR has remained constant over the period to 2006 "We have increased the CO2 in the atmosphere about 17% from 1970 to 2006 (328ppm vs. 383ppm) and the OLR appears to have remained constant when you look at the raw data from these three papers". Essentially we have over 30 years of satellite data which seems to show no overall decrease in OLR and possible an overall increase (didn't read all the comments) My understanding is OLR has increased over the full satellite period, but I could be wrong, so: Has OLR slightly decreased, slightly increased, decreased significantly, increased significantly or stayed the same over the satellite period? If OLR has increased to any extent, what are the possible causes? If OLR has increased to any extent does this invalidate the enhanced green house effect hypothesis? TIA
  16. The Debunking Handbook Part 1: The first myth about debunking
    John... This looks to be a great resource that I'd like to hand out to a few people. A suggestion, please consider adding permission to the PDF to be duplicated as many commercial copy shops will not allow copies to be made by them without it.
    Response: [JC] Good idea, thanks for the suggestion.
  17. World Energy Outlook 2011: “The door to 2°C is closing”
    Or "is worth a thousand words". But Grandma was french.
  18. World Energy Outlook 2011: “The door to 2°C is closing”
    "A picture is worth than a thousand words" (Grandma et al.)
  19. There's no tropospheric hot spot
    Is there such a thing as a graph showing the actual observed data - not prepared by Monckton that both sides can agree on?
  20. There's no tropospheric hot spot
    @9 Can't win, can I? If I ignore links to SkS I'm condemned as a "denier" for not listening to both sides and if I engage with readers of SkS I'm immediately pounced upon to confess my sins. In answer, yes I have read the advanced tab and no I am not convinced, hence the questions
  21. World Energy Outlook 2011: “The door to 2°C is closing”
    Edmh's assertion of 12% is off by a factor of 10. The real increase is 120%, not 12%. Just to clarify things for readers who may fall for the pseudo-logic of non-mathematical declarations that do not include actual math, Edmh's false and unsupported assertions amount to (I assume, since his rambling, emotional assault was so thin on details):
    • CO2 effects are logarithmic.
    • The difference in forcing from the current level of 390 ppm to a doubling of the preindustrial value of 285 ppm to 570 ppm will only represent a 12% increase in forcing over the current level.
    Let's look at that. A doubling of CO2 from 285 ppm will increase temperatures by 3 degrees. This can be written as:
    ∆T = 3•log2 (ppm-CO2/285)
    Forcing at 285 ppm is presumed to be our base, that is
    3•log2(285/285) = 3•log21 = 0˚C
    Put into words, a zero increase over the base level of 285 ppm has no effect on mean global temperature. Forcing at 570 ppm (double the original) is a factor of 1, that is
    3•log2(570/285)= 3•log22 = 3˚C
    Put into words, a doubling of CO2 to 570 ppm increases temperatures by 3˚C. Forcing at 390 ppm (where we were a few years ago, we're now at 395 ppm) is 1.36˚C, that is
    3•log2(390/285) = 3•log21.37 = 3 • 0.454 = 1.36˚C
    Put into words, if we stopped right now the global mean temperature would rise, with time, to a point 1.36˚C above the general global mean for the past 5,000 years (but with all of the same natural variation seen in the last 2,000 years of about ±0.3˚C). The difference between a doubling, 3˚C, and the current forcing, 1.36˚, is
    3 - 1.36 = 1.64 ˚C.
    So if we succeed in stopping at a doubling of CO2 (which deniers like Edmh strive to prevent us from doing by arguing against any action at any time) then that added CO2 will increase temperatures 1.64˚C beyond the 1.36˚C to which we have already committed ourselves, or as a percent
    100 • 1.64 / 1.36 = 120.5%
    120.5%. Not 12%. Off by an order of magnitude -- a factor of 10. And, of course, what we really care about is temperatures, not percents. We are rolling the dice and gambling with civilization and hundreds of millions if not billions of lives even if we stop at 2˚C. Policy analysts hope that 2˚C won't be so bad that hundreds of millions die or become refugees, and the resulting burden on the economy and food production doesn't overwhelm us all. And this assumes that climate sensitivity really is only 3˚C per doubling. Current estimates are in the range of 2˚C (increasingly unlikely) to 4.5˚C. So that equation could be 3.5•log2CO2 or 3.8•log2CO2 or 4.5•log2CO2 or worse yet even 5•log2CO2. We are at 1.36˚C. If we want to stop at 2˚C, we need
    3•log2(X/285)=2.0 log(x/285) = 2.0 / 3 x/285 = 22.0 / 3 x = 285 • 22.0 / 3 = 285 • 1.59 = 452 ppm
    450 ppm is a number you may have seen recently. Like in this post (up above, The 450 Scenario). And, of course, even a 120.5% increase in forcing presumes that we are able to stop cold at 570 ppm.
  22. Eschenbach and McIntyre's BEST Shot at the Surface Temperature Record
    Carl Thanks for dropping by to SkS and for the kind words (and brickbats). I was the author behind the opinions about STAR, Fu & V&G so let me clarify my intent. This post and my linked post on the satellite data began as a response to a post by Willis Eschenbach at WUWT. We at SkS often find we are trying to correct misinformation about the published science, often of a vague and misleading nature. However in the case of the post by Eschenbach I felt he was making an unreasonably definite staement about the degree of accuracy in the satellite temperature products. Perhaps he intended that as a means of casting too much doubt on the quality of the surface temperature products, presumably as a means of suggesting that they have a 'problem' and UHI is the likely culprit - ignoring the fact that the surface records include corrections for UHI. As you are probably well aware, the various temperature records have become quite politicised, with 'skeptics' using whichever record could seem to bolster their claim, until they switched to another claim. So some years ago, when the UAH & RSS TLT products still showed significant differences the lower UAH product was always the skeptics darling. Since the two products are now giving similar results, this seems to have dropped away. What I wished to do with this post was to highlight to a general audience that there are actually 5 different groups who are or have examined the satellite data and reached somewhat varying results. The work by the Star, Fu & V&G teams appears to be virtually unknown outside scientific circles compared to the UAH/RSS products. I also feel that getting a graph of the weighting functions for the different channels in front of as many eyeballs as possible was an important exercise in informing people that the satellite records aren't as clearcut and black-and-white as they sometimes portrayed in the Blogosphere. To your specific criticisms. The basis for the numbers for Fu are taken from Fu et al 2004, Fig 3. The bar graph highlights the difference between the basic T2 results from both RSS & UAH and the same values when the Fu method was applied to produce their T850-300 result. The key point I wished to convey was how much the Fu method altered the original T2 values. And the figure of around 0.2 comes from this graph. I do point out that this is from earlier data and provide a link to the NOAA site for the current Fu adjusted figures. I have included the weighting function for the Fu product to allow the reader to see the effect it has and that in particular its peak weighting is at essentially the same height as T2. To your comments about the Star data and suggesting a TLT trend from it. I know they don't yet have a TLT product although it is in the works. My purpose here was simply to highlight that since their SNO method is producing a significantly higher TMT value than either RSS or UAH, that a TLT trend when they produce it could well be higher as well. In this respect I was simply trying to suggest what seemed plausible. My comments there were: "So what trend would Zou produce if the TLT calculations were added as well? We can’t know for certain yet, but they must be higher than UAH or RSS simply because their starting point from the TMT trend is so much higher. For a definitive answer we will need to wait for their analysis. But we can possibly make a ballpark estimate. If we simply take the difference between the TMT and TLT values for RSS & UAH as being indicative of how much the TLT processing adds to the underlying TMT trend, and add them to the Zou teams TMT trend we might get some idea". Not intended to be definitive, just suggestive. Hopefully the Star team will be able to produce their TLT product soon so we can gain clarification. The thrust of this post was arguing against the implicit claim made by Eschenbach that particular temperature products were significantly better quality than others wereas it seems from the work of all the teams working on both surface and satellite temperature analyses that you are all converging towards a common point in the analysis but it is not yet completely clear how close each teams results are to that desired definitive result. You are all circling the target and a prettty damn close. And my hat is off to you guys working on the satellite data. That is one hell of a tricky problem, teasing meaning out of such a complex problem. If you have any further comments we would be glad to hear them, or if you were interested in writing a guest post on some of these topics, John Cook would love to hear from you. As an aside, a personal interest of mine, which I included as a speculation at the end of my post, is whether it is possible to apply a method akin to the TLT algoritm or the Fu method to tease out an upper Tropospheric signal without the stratospheric cooling bias. Looking at the weighting functions for TTS and TLS and their corresponding trends from UAH, RSS and Star, it certainly seems plausible that the TTS signal is indicative of a warming upper troposphere combined with a cooling stratosphere. Is such an analysis technically possible and do you know if anyone is planning such a project. I don't know what the scientific utility of such an analysis might be but it would certainly be useful as a data product in the public debate about AGW.
  23. World Energy Outlook 2011: “The door to 2°C is closing”
    Edmh @26, first, your "summary" contains multiple denier myths, including the canard that CO2 only contributes 5% of the greenhouse effect. You add a few straight out falsehoods of your own, including a claim that CDIAC disagrees with the IPCC about the temperature effect of increased CO2 concentrations. Indeed, your table of temperature effects is best described as a complete fiction. More troubling is your claim in your spreadsheet that an increase in atmospheric CO2 from 900 to 1000 ppmv would have no effect on temperatures. In fact, given the best estimate of climate sensitivity, it would increase Global Mean Surface Temperature by over 0.4 degrees C. In fact, given reasonable estimates of fossil fuel reserves, we can increase atmospheric CO2 concentrations to levels well beyond 5000 ppmv, with consequent forcings significantly greater than any experienced from the combined effects of solar and CO2 concentration changes since the evolution of the first vertebrate, the common ancestor of all fish, amphibians, reptiles, birds or mammals. Further discussion of this topic can be found where is it on topic, ie, the rebuttal of the denier myth that The CO2 effect is saturated.
  24. The Last Interglacial Part Five - A Crystal Ball?
    skept.fr #1 - If you are asking if it's possible to infer local as in specific regional temps, then no. Local temps are influenced by numerous factors such as vegetation, proximity to ocean, prevailing wind direction etc. Modelling estimates that the various forcings in play during the Eemian led to a global temp of up to 1 degree C above present day. Arkadiusz Semczyszak #7 - Whilst Rundgren et al (2005) provides an interesting and useful result, it needs to be taken in the context that it's based on a leaf stomatal index proxy with whopping great error bars.
  25. Arkadiusz Semczyszak at 20:45 PM on 17 November 2011
    The Last Interglacial Part Five - A Crystal Ball?
    MIS 11 - it is worth noting that here too we have serious objections: Rohling et al., 2010.: “MIS-11 is often considered as a potential analogue for future climate development because of relatively similar orbital climate forcing ...” “However, there is an obvious difference in that the current interglacial (Holocene) spans a single insolation maximum (summer, 65°N), while MIS-11 spanned two (weak) astronomical precessiondriven insolation maxima separated by a minor minimum (due to coincidence of a minimum in 400-ky orbital eccentricity with a maximum in the Earth's axial tilt ...”
  26. Arkadiusz Semczyszak at 20:45 PM on 17 November 2011
    The Last Interglacial Part Five - A Crystal Ball?
    Solar variability. It is worth recalling how much "link to orbital eccentricity," must be amplified to explain the creation (and end) - not just the last - interglacial. Beer et al., 2000.,: “If one computes the global and annual mean of solar forcing caused by the 100 kyr period of eccentricity one gets an amplitude of in the spherical mean. This value is too small to be detected in climate records. But, despite the tiny global forcing value, we can observe the 100 kyr frequency during the last 800 kyr in most paleoclimatic records. The global mean temperature changes between glacial and interglacial periods are large: about 20C for polar (Johnsen et al., 1995) and 5 for tropical regions (Stute et al., 1995).” Beer et al. 2006. : “ Note that the mean annual global insolation changes caused by the eccentricity are very small (<2.5 Wm −2 )” “The existence of feedback mechanisms is illustrated by the discussed glacial-interglacial cycles that are related to a [-all caps snipped-] annual mean change in insolation.” “This implies that the climate system has the potential to respond significantly to even [-all caps snipped] forcings and that this response may depend strongly, not only on the amplitude, but also on the duration of the forcing with potentially larger effects for longer lasting or repeated forcings.”
    Moderator Response: (Rob P) No more all caps please. You have commented here long enough to know the rules. Further breaches may result in your post being deleted.
  27. Arkadiusz Semczyszak at 20:44 PM on 17 November 2011
    The Last Interglacial Part Five - A Crystal Ball?
    Atmospheric CO2 during the Last Interglacial was comparable to the pre-industrial Holocene and reasonably stable ... Is worth to draw attention - Rundgren et al., 2005. - on Figure 4 - "raw" data. Together with a possible range of deviations - fluctuations of CO2 are possible (and in a relatively short time) between 160 and c. 350 ppmv CO2. Changes in the Eemian p.CO2 may thus be significantly underestimated. These changes, however, took place in a relatively short period of time: „... centennial to millennial changes were followed by more rapid CO2 oscillations within the range of c. 255–285 ppmv between c. 2700 and 3000 years after the onset of the Eemian.” Of course these changes are smaller and slower than today, but if you can call them: „reasonably stable” ?
  28. Dikran Marsupial at 20:36 PM on 17 November 2011
    World Energy Outlook 2011: “The door to 2°C is closing”
    Edmh The radiative forcing from CO2 rises only logarithmically with the concentration, so in a sense, yes "effect of CO2 as a Greenhouse gas becomes ever more marginal with concentration". However the point that you are missing is that CO2 concentrations are rising approximately exponentially, which means that CO2 radiative forcing (the effect on the climate) is rising linearly. "From the present position of a atmospheric CO2 concentration of ~390 ppmv, there is only ~12% of the effectiveness of CO2 as a Greenhouse Gas remaining even as emissions increase." This is simply incorrect, logarithmic relationships have no upper limit.
  29. World Energy Outlook 2011: “The door to 2°C is closing”
    But the effect of CO2 as a Greenhouse gas becomes ever more marginal with concentration This article is predicated on the suggestion that a temperature rise of +2 degC must not be exceeded Remarkably, IPCC Published reports themselves show that the effective temperature increase caused by growing concentrations of CO2 in the atmosphere radically diminishes with increasing concentrations. The effectiveness of CO2 as a greenhouse gas is well understood in the climate science community to reduce logarithmically as concentrations increase. Although the IPCC accepts that this crucial effect exists, it certainly does not emphasise it. The IPCC does not explain the devastating consequences of this fact in their Summary for Policy Makers, and it thus fails to provide conclusive support for its claim. When it states "Warming of the climate system is unequivocal. Most of the observed increase in global average temperatures since the mid-20th century is very likely due to the observed increase in anthropogenic greenhouse gas concentrations." Thus any unquestioning, policy making reader is unequivocally lead to assume that all increasing CO2 concentrations are progressively more harmful because of their escalating Greenhouse impact. This is not so. From the present position of a atmospheric CO2 concentration of ~390 ppmv, there is only ~12% of the effectiveness of CO2 as a Greenhouse Gas remaining even as emissions increase. These guys miss the crucial point that only 12% of the effectiveness of CO2 as a GHG remains however much the concentration of CO2 increases So however much CO2 is emitted its never going to have that 2degC effect And nobody seems to see this (-snip-) flaw in the alarmist argument see http://diggingintheclay.wordpress.com/2011/09/21/quantifying-co2-mitigation/ read the summary at the end
    Moderator Response:

    (Rob P) All Caps edited.

    [DB] "But the effect of CO2 as a Greenhouse gas becomes ever more marginal with concentration"

    Incorrect.  Please support this assertion with a link to a reputable source.

    "The effectiveness of CO2 as a greenhouse gas is well understood in the climate science community to reduce logarithmically as concentrations increase."

    Incorrect.  The temperature rise produced by logarithmic increases concentrations of CO2 rises is about 3° C per doubling.  Thus, there is no loss of "effectiveness".

    "Although the IPCC  accepts that this crucial effect exists, it certainly does not emphasise it."

    This "crucial" effect does indeed exist, as I have described it.  That the IPCC fails to "emphasise it" to your satisfaction is your issue.

    "The IPCC does not explain the devastating consequences of this fact in their Summary for Policy Makers, and it thus fails to provide conclusive support for its claim."

    IBID.  Inflammatory tone struck out.

    "Thus any unquestioning, policy making reader is unequivocally lead to assume that all increasing CO2 concentrations are progressively more harmful because of their escalating Greenhouse impact. 

    This is not so.   "

    Unsupported assumptions, speculations and allegations, on your part.

    "From the present position of a atmospheric CO2 concentration of ~390 ppmv, there is only ~12% of the effectiveness of CO2 as a Greenhouse Gas remaining even as emissions increase."

    Incorrect, as Dikran points out subsequent to your comment.

    "These guys miss the crucial point that  only 12% of the effectiveness of CO2 as a GHG remains however much the concentration of CO2  increases"

    Repetitively incorrect and IBID.

    "So however much CO2 is emitted its never going to have that 2degC effect"

    IBID, and spectacularly so.

    Inflammatory tone snipped.  Less ideological posturing and more emphasis on using citations to reputable sources would begin to lend you credibility.  And if you are just another sock puppet of Galloping Camel/Peter Morcombe:  you know better than to continue your modus operandi as above.

  30. How to Avoid the Truth About Climate Change
    An excellent talk - give or take the sound quality ;) A clear exposition of arguments always gives one room to think... something occurred to me re the Galileo gambit: Ignoring the appalling revisionist history of the "Galileo Movement", the point that was made clearly in the talk is that Galileo, and the other astronomers of the time, where trying to match their observations to a 'physics' model, not a Physics model. The Physics model awaited Newton and then Einstein for further refinement. Once we had that, the observations made a lot more sense, 'bad' observations could be spotted more easily, the 'killer argument' data defined. There is a parallel, for example, with the "it's natural cycles" brigade and the pure trend / spectrograph analysers. They are doing 'physics' and ignoring the Physics. If, in the spirit of charity, one where to lend Galileo to the truth-challenged, for the moment... Then they are identifying them selves with a methodology which connects assumption to observations without intervening Physics insight. Worth noting that to accomplish this, many people spend much time trying to undermine the Physics / models etc.
  31. The Debunking Handbook Part 1: The first myth about debunking
    As alan_marshall #1 said!
  32. Philippe Chantreau at 19:06 PM on 17 November 2011
    World Energy Outlook 2011: “The door to 2°C is closing”
    I will add that I am no advocate for biofuels, which do not make sense in their current schemes of production, from a carbon budget point of view. Large agri-businesses are the main actors pushing these fuels. they are carbon inensive in their production that they do not present any significant advantage.
  33. Philippe Chantreau at 19:01 PM on 17 November 2011
    World Energy Outlook 2011: “The door to 2°C is closing”
    I understand what your point was skept; however, it should have been worded rather as "may have participated in" since, as you pointed yourself, some research failed to find any evidence tha it actually did. As is stands now, there is no single greater threat to the World economy than speculation and the behaviors of the major actors in the economy. As a risk, speculation dwarfs the effect of any possible climate mitigation policy by orders of magnitude. It is bad behavior, wishful thinking and speculation that brought the current crisis, costing literally trillions. I'm sure you'll then understand that I'm unimpressed by a problem that has not been showed to be significant, let alone exist at all. I would take the economic concerns of skeptics more seriously if they were ever ready to address, or even acknowledge the real economic problems, the kind that can demonstrably cause a crisis like the current one.
  34. The Last Interglacial Part Five - A Crystal Ball?
    5, skept.fr, ClimateWatcher's references to the Eemian and Holocene were a throwaway statement intended to let him say anything he wanted without seeming to be off-topic. His real intent was to carry forth the lame denier meme that since summer/winter temperatures/insolation vary so greatly within each year that CO2 variations must be comparatively negligible.
  35. Extreme Events Increase With Global Warming
    Norman#61: First of all, quoting a smattering of links is hardly deserving of the term 'research.' Second: Your NASA link on blocking? Stalled Weather Systems More Frequent in Decades of Warmer Atlantic The researchers observed the frequency of blocked weather events in the North Atlantic ... over the entire twentieth century and compared it to the evolution of ocean surface temperatures for the same area. They then removed the effect that global warming has on water temperatures, and found that decades with more frequent, recurring blocking events in the North Atlantic corresponded to those decades when the North Atlantic Ocean was warmer than usual, as it is now. Nothing there about global warming - by design. Your 'Abstract describes': Winters with clusters of more frequent blocking between Greenland and western Europe correspond to a warmer, more saline subpolar ocean. It's not clear from that whether blocking causes warming or warming causes blocking.
  36. Extreme Events Increase With Global Warming
    "If the blocking patterns remain the same with global warming, I see no logical reason to assume more extreme heat waves (greater frequency)." Norman, your final paragraph in #61 seems to explain where you are going wrong. You seem unable to understand what happens when you shift a Gaussian distribution to the right. Tom Curtis in #61 does a good job in trying to explain. You do realise that the graphs in Hansen et al 2011, posted by muoncounter in #30, directly contradict your above claim, and that these are observations?
  37. Extreme Events Increase With Global Warming
    muoncounter @58 and DB, Here are some of the sources of the blocking patterns argument. First comes from skywatcher's post 44 on the "Review of Rough Winds: Extreme Weather and Climate Change by James Powell" In Stu Ostro's presentation he shows how extreme weather is caused by numerous blocking patterns. skywatcher link in post 44. NASA research on blocking patterns. Old article on blocking patterns. abstract describes how blocking can lead to warming. blocking patterns. Tony Lupo to study blocking. There are many others all saying close to the same thing. Blocking patterns create much of the extreme weather we experience. Heat, cold, snow, rain (in the extreme). My point is not that absurd or farfetched and it seems all who study the phenomena are in agreement as to what it will do to regional weather. If it can be demonstrated that global warming increases blocking patterns, then it would logically follow that global warming will result in more weather extreme events. Otherwise it would just be factual that global warming will raise the avearge temperature and make things warmer. If the blocking patterns remain the same with global warming, I see no logical reason to assume more extreme heat waves (greater frequency). I would agree that the heat waves that do occur will be warmer (by a few degrees) than similar heat waves in the past.
  38. Extreme Events Increase With Global Warming
    Norman @48 and @55, you appear to working under several misconceptions. First, nobody is denying that meteorological, and major climactic events have the dominant role in day to day weather. There is a drought in Texas because of a La Nina event. There was a heat wave in Moscow because of a blocking event. Trivially, the probability of exactly identical heatwaves of blocking events occurring at exactly the same time without greenhouse gas forcing is almost zero (butterfly effect); but almost as trivially and far more importantly, La Nina's and blocking events would have occurred at very similar frequencies in the absence of GHG forcings. What is being claimed is that global warming influences the events that occur so that very high temperatures become more common than they once where. Second, you can approximate to the effect of global warming by simply adding the monthly value of the trend in global warming to the monthly or daily temperatures. This is a very crude approximation, but it does not lead you totally astray. Based on that, for example, John Nielsen-Gammon (state climatologist for Texas) argues that:
    "This record-setting summer was 5.4 F above average. The lack of precipitation accounts for 4.0 F, greenhouse gases global warming [edited 9/11/11] accounts for another 0.9 F, and the AMO accounts for another 0.3 F. Note that there’s uncertainty with all those numbers, and I have only made the crudest attempts at quantifying the uncertainty. But this will do until something better comes along."
    I would quibble that the drought was partly the result of the heat, so that some of the "drought contribution" is a secondary effect of global warming. But Neilsen=Gammon's position is perfectly reasonable. You could also as a crude model simply add the regional global warming anomaly to the Russian heatwave and say that that was the contribution of global warming. That contribution is not 0.8 degrees C, ie, the global anomaly, but closer to 1.8 degrees C (four decades of the decadal trend) for the Moscow region). But using the correct figures, the approach is not unreasonable. Using that approach, you would say that global warming added 1.8 C to the 6.67 degree C July 2010 Moscow anomaly, or 27%. However, leaving the analysis there seriously underestimates the effect of global warming on the return frequency of extreme events. For example, even a 0.8 degree C increase in mean temperatures represents a significant fraction of a Standard Deviation. For high Standard Deviation events such as those in the US in 1936 or Moscow in 2010, even a small increase in temperature can greatly increase the return interval. As an example of this, your state SD of the Bismarck record was 5, whereas, the actual value was 4.89. That 0.11 difference in SD increases the return interval by more than 70%. That is, a 0.67 degree C increase in temperature can increase the return inverval from 32,000 years to 56,000 years assuming normal distribution. For actual values found such as the Moscow event, the return interval can be increased from 1 in 260 year events to 1 in 1000 year events just by that small difference in temperature. Hence, using this crude model, the only logical conclusion is that global warming significantly reduces the return period of extreme temperature events. Finally, and briefly, it is not at all clear that the crude model is in fact warranted. There is evidence that global warming is changing the frequency and intensity of ENSO episodes (although the evidence is not conclusive). There are good logical reason to expect a non-stationary climate, ie, one significantly warming over time, to not be as well behaved as a stationary climate. These are areas around which there is legitimate debate. But without venturing into those areas, the conclusion you are arguing against follows directly from your own premises. And a final note about your 52, despite the many records set in the state, the map you show (as also the one from GISS) shows the highly localized nature of the very extreme heat. Further, I'll see your 17 states from 1936 and raise you 19 national records from 2010.
    Response:

    [DB] Fixed html issues.

  39. Extreme Events Increase With Global Warming
    Norman, please, please go look at the Hansen graph that muoncounter linked to in #30. It demolishes your statement in #55, and I really would like you to understand that. The 'modest' global warming we have experienced has greatly increased the chances of seeing a 'hot' or 'extremely hot' spell of weather. That's not projected, that is from observations. We should hope that blocking patterns (whatever your 'research') don't materially increase in a warming world - Hansen's and R & C's work show that the increasing number of extremes needs no help...
  40. Extreme Events Increase With Global Warming
    Norman#55: "The research I have done on the topic still indicates ... " OK, out with it. Trenberth, tamino, Hansen, R and C have all put their work on the table. Call: What cards do you have, other than your Bismarck ace-in-the-hole?
  41. Extreme Events Increase With Global Warming
    Norman#48: "the current amount of global warming would only increase the average a few degrees." Well, that's a start; despite the fact that it reveals a very basic misconception. The key word in that statement is global. Increasing the global - or even hemispheric - average temperature by 'a few degrees' is a lot of warming. But your fascination for individual location, short term records is more of the same 'I can't see it, so its not happening.' How does one month in Bismarck, ND equate to all of Europe showing a significant increase in the number of summer days much warmer than a 30 year average? The graphs here include your 1936 heat wave. At that time, approx 40% of the NH land area saw summers classified as 'hot' and very little area was classed as 'extremely hot.' Now we see approx 80% 'hot' and nearly 20% 'extremely hot.' What happened in Bismarck this past summer is just a tiny spot out of that land area. How can you continue to miss this point?
  42. Extreme Events Increase With Global Warming
    Norman @50, the data source you link to is just the daily temperatures for July 2011. That is a small data set, and distorted high by global warming. More importantly, it is a daily mean. The July 2010 temperature often quoted for Moscow was a monthly average. That means while, assuming a normal distribution and no global warming, the probability of a Moscow 2010 heat wave is only 1 in 66,667 in a given year, the probability of a Bismarck maximum under the same assumptions, and using your data is only one in every 32,258 years. Of course, temperature records are not normally distributed. Accounting for that, and for global warming, Tamino shows that the average return interval of a Moscow style heat wave is 260 years given the current level of global warming, or close to 1 in every 1000 years without global warming. (Note that that makes the event 4 times more likely based on global warming, an independent confirmation of Rahmstorf and Comou.) The correct estimate of the temperature record for Bismarck requires a similar detailed analysis to that provided by Tamino, using more than a single months data. One thing we can be sure of, however, is that the result will (once again) show the event to be significantly more probable than the Moscow event. Finally, you still appear to be arguing that because you can role a '12' on a pair of standard dice, that shows you will not role '12's more frequently if you use a standard die, and a second die numbered '2' to '7'. Such an argument is a game effort in denialism, but is doomed to failure for anyone prepared to look at the data logically.
  43. Extreme Events Increase With Global Warming
    Rob Painting @53 Yes that is true, the cold extremes would diminish and the warm extremes would increase. I agree with this logical thought process. As I look at Figure 1 from you above original post, I know the current global warming is about 0.8 C. This would shift the distribution curve just slightly to the right. Not enough to really affect the 2010 Moscow anomaly either way or make it more likely. If the model projections for global warming are correct with a large temp increase (due to possibility of enhanced effects...doubling CO2 levels by themselves will only raise the global temp a couple of degrees) then the shift will definately make 2010 events much more likely as they become normal events. The research I have done on the topic still indicates that blocking patterns caused this heat wave and the pattern would have taken place regardless of warming.
    Response:

    [DB] "Not enough to really affect the 2010 Moscow anomaly either way or make it more likely."

    Based on what citation do you state this so authoritatively?

    "The research I have done on the topic still indicates that blocking patterns caused this heat wave and the pattern would have taken place regardless of warming."

    Then feel free to submit that research for publication in a reputable journal.  In the meantime, you continue to prosecute your agenda of selective cherry-picking & disregarding all evidence that doesn't conform to your preset view of things.

    Shorter response: you continue to waste the time of others here.  For now.  This will not last, however...

  44. Extreme Events Increase With Global Warming
    Norman, the question you are failing to answer is this: Why does the existence of any past individual event change anything about the increasing probability of extremes in a warming world? Your #50 is irrelevant - all it shows is that in the map for 1936 a la Hansen et al 2011, North Dakota would have experienced a >= 3-sigma event and been coloured brown. Otto would have had a hot summer had he been in the town named after him. You're still avoiding the focus of everyone's issues with you: that nobody here doubts that large extremes happened in the past. But the data here (Hansen and R & C) provide strong evidence for the frequency of heatwaves increasing - the Gaussian distribution flattening slightly and shifting to the right, and each year, a greater proportion of the Earth's surface experiences extremes. Without being pejorative, I do wonder if you get what probability is all about?
  45. Extreme Events Increase With Global Warming
    Norman @52 -"It was also the coldest February recorded in the US. It has the record number of consecutive days below zero in the lower 48th (41 days). Yes, hardly a surprise given this occurred early in the observational record. This asymmetry of warm vs cold records is discussed in Rahmstorf & Coumou, although I don't deal with it in the blog post. I you take a gander at Figure 1 in the post above, that's a gaussian (or normal) distribution. Keep moving that distribution to the right (climate warming trend) and the cold extremes (to the left) gradually diminish. In other words the frequency of record-breaking cold extremes decrease - as observed in figure 2 in both the GISS data and the Monte Carlo simulations.
  46. Extreme Events Increase With Global Warming
    Tom Curtis @46 You do have excellent posts. I would suggest you click on the source of the 1936 graph of the heat wave (1st graph). From the larger article the graph was part of: "Seventeen states broke or equaled their all-time record absolute maximum temperatures during the summer of 1936 (still standing records)." It was a large extent pattern and if you look into the article you will see it started in June and set state records, extended and grew in July and then persisted in August setting records in all three months so it was quite large and enduring. The amazing thing about 1936 is that not only was it very hot in the summer, it was the extreme of extreme years. It was also the coldest February recorded in the US. It has the record number of consecutive days below zero in the lower 48th (41 days). In the article they list many of the record high temps.
  47. Extreme Events Increase With Global Warming
    Norman @ 43 - Just to add to the comments made by others, the important point you miss is the warming climate leading up to the North American heatwave made a record-breaking warm extreme more likely. You provide evidence that actually supports the findings of Rahmstorf & Coumou. So once again: In a stationary climate (no warming trend) the probability of record-breaking falls (the 1/n rule). This doesn't mean that natural variability alone cannot break records, just that the odds decrease with each subsequent observation. In a warming climate the probability of record-breaking warm extremes increase. This assumes of course, that the standard deviation follows a gaussian distribution - which it does in the case of the GISS global and Moscow July temperatures. As Tom Curtis has already pointed out to you, arguing probability on the basis of a singular event is an illogical premise.
  48. Extreme Events Increase With Global Warming
    skywatcher @47 I ran a standard deviation of Bismark, North Dakota July 2011 data (should be fairly typical for that area it would seem as the average temp came very close to the long term average for this area). Using this standard deviation calculator found here. I entered data from here. into the standard deviation calcualtor. The results were: Mean: 84.26 F Standard Deviation: 6.07 The record high in July for Bismark is 114 F set in 1936. 114 F is sigma 5 (5 standard deviations away from the mean).
  49. Extreme Events Increase With Global Warming
    This Science Daily item might explain a few things that perplex some of us about extreme weather events . Erratic, Extreme Day-To-Day Weather Puts Climate Change in New Light I hope someone will soon do a post here on this AMS Journal of Climate paper "Trends in daily solar radiation and precipitation coefficients of variation since 1984." from Medvigy & Beaulieu. I don't recall their names but this stuff looks interesting and relevant for those trying to get their head around the implications or causes of extreme weather effects. It will be interesting even if it only evokes a more detailed analysis from others disputing or elaborating on the results they have so far.
  50. Extreme Events Increase With Global Warming
    muoncounter @45 "If you accept the Hansen paper's data as accurate - and you've posted a GISS graph, so I have to assume you do - then how can there not be an increased probability of heat waves?" I would agree that the average temperatures will be higher but the current amount of global warming would only increase the average a few degrees. That is because I do not feel that exterme heat waves are random fluctuations in the temperature field but are caused by patterns that develop. The NASA article I am linking to does suggest global warming may increase heat waves. That is because it is possible global warming of the oceans may produce more blocking events. In this way I can accept that global warming can lead to more heat waves. But the NASA article can easily explain the Hansen data posted in #5 by Albatross. Blocking patterns have been changing with time and are controlled by the ocean temperature. When researchers get a complete picture of what causes and maintains blocking patterns it will then explain if global warming will increase the probability of heat waves. If global warming causes blocking patterns to decrease then I would not believe the probability of heat waves would increase. Though I would believe the average daily temperature would increase. NASA article on blocking patterns.

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