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Comments 74651 to 74700:

  1. Trenberth, Fasullo, and Abraham Respond to Spencer and Braswell
    This is just yet another in a mountain of examples of WUWT spinning and misrepresenting the science to further their own ideological agenda. But of course Pielke Sr. says it is an excellent science site and that he thinks Watts is "devoted to the highest level of scientific robustness". This is what these guys does, they ignore or forget that a paper has been refuted and that the science has since moved on and simply keep rehashing the same old mantra. They seem to think that if one keeps repeating an error that it becomes truth. Well it doesn't. What is also lost on them is that why would anthropogenic forcing be the first external forcing to not result in a net positive feedback in the climate system (paraphrasing Dr. Nielsen-Gammon)? How does one explain the medieval warm anomaly of interglacial if a strong negative cloud feedback is operating? You don't. They do not get it because they do not wish to--- their ideological blinkers are obscuring their objectivity and their logic.
  2. Observations of Climate Change from Indigenous Alaskans
    For another chilling first-hand account of climate change's impact on the Arctic, check out: "Rare Arctic creatures in trouble" posted on CNN today (Sep 20, 2011).
  3. Hockey stick is broken
    KR, All proxies could be considered cherry-picks, as we do not have a uniform global coverage. I do not know how you could possible make that statment recarding the Lundqvist paper, as it clearly states, "The highest average temperatures in the reconstruction are encountered in the mid to late tenth century," and "The temperature of the last two decades, however, is possibly higher than during any previous time in the past two millennia, although this is only seen in the instrumental temperature data and not in the multi-proxy reconstruction itself." Portions of the globe have cooled during the twentieth century, but that does not mean that global temperatures have decreased.
  4. Hockey stick is broken
    An error on my part in my last posting - the Oppo 2009 article states that SST's in the Indo-Pacific warm pool were similar to modern values. But please note that, as Rob Painting pointed out, the MWP was not uniform spatially: Portions of the world were fairly warm during the MWP, portions were much cooler. The global temperature was not as warm as present, and you are cherry-picking spot measurements.
  5. Hockey stick is broken
    Jonathan - Not one of your references supports your assertions. The Ljungqvist data directly contradicts you, see the New temperature reconstruction thread. Current temperatures are higher than anything in the last millenium. From your second link, Oppo 2009, the abstract states - "Reconstructed SST was, however, within error of modern values from about ad 1000 to ad 1250, towards the end of the Medieval Warm Period. SSTs during the Little Ice Age (approximately ad 1550–1850) were variable, and approx 0.5 to 1 °C colder than modern values during the coldest intervals." (emphasis added) The Greenland GISP2 data is interesting, and very limited. See the entire discussion at Crux of a Core, multiple parts. Primarily, that is not a global record. Please - read the works you link to. Currently you appear to just be making stuff up.
  6. Hockey stick is broken
    First, with one exception, the graphs show that recent temperatures are the warmest in ~500 years. I have no argument with that statement; and many scientific association seem to agree, as many of their statements claim that recent temperatures are higher than any time in the past four centuries. They have backed away from claims of the past millenium. The following are a few temperature reconstructions in peer reviewed literature that support my earlier statement. Also, see the Greenland ice core data in post #59. You seem to be selectively choosing that data which supports your position, while ignoring that which does not. This is similar to what you are saying about using proxies to misrepresent the data. http://www.nature.com/nature/journal/v460/n7259/abs/nature08233.html http://agbjarn.blog.is/users/fa/agbjarn/files/ljungquist-temp-reconstruction-2000-years.pdf Recent temperatures may very well be warmer than any tiem in the past millenium. However, there is sufficient data in the literature which shows otherwise.
  7. Positive feedback means runaway warming
    102, jpat, But you cannot accurately depict this system with such a simple differential equation, hence a graphical representation of such an equation is no more accurate or applicable than the equation itself. The last time I checked, using a hammer to propel a car forward was ineffective, even though the effort does not overturn belief in hammers as effective nail-driving instruments.
  8. One-Sided 'Skepticism'
    207, Philippe, Thanks for the links. In particular, I've been looking for more history on "who knew what and when" in the MSU/UAH satellite temperature record debacle. It doesn't tell everything, but it at least fills in some of the blanks. It would be good to understand exactly how resistant Spencer and Christy were to correcting the problems in their data, and why it fell to others (Mears et al) to ultimately find the issue.
  9. Hockey stick is broken
    Jonathan - "Because no significant difference has beenestablished between the NH temperatures then and today." That's not just wrong, that's blatantly wrong, and contradicted by the peer reviewed literature. As CB said, read above! I'm puzzled as to why you would make such an unsupportable statement.
  10. Positive feedback means runaway warming
    I'm done here but one final note. The toy model presented above is not an electrical circuit, its a graphical representation of a differential equation. Last time I checked Poincare and LaPlace had not been overturned.
  11. Chasing Pielke's Goodyear Blimp
    Memo to my fellow SkS authors: Let's change the damn "Christy Crocks" button and move on!
  12. Are you a genuine skeptic or a climate denier?
    Dana69:"Therefore analysis in detail, leading to meaningful forecasts or projections, is fundamentally impossible in principle." Surely you can tell that's a patently absurd conclusion, generated from an improper application (or understanding) of chaotic systems. The climate where I live can be described very simply: hot and humid in the summer, cool and humid in the winter. The point is that climate is determined over a long-period; individual chaotic events average out.
  13. Hockey stick is broken
    Jonathon wrote: "Because no significant difference has beenestablished between the NH temperatures then and today." That statement is simply false. As extensively documented in the post at the top of the thread.
  14. Trenberth, Fasullo, and Abraham Respond to Spencer and Braswell
    @2,3,4 I think commenter Bart Verheggen was quick to point out that Watts has misunderstood the paper, and none other than Roy Spencer confirmed it. Another commentator ('Fredb' - ??) referred to some of Watts’ language in the post: "... can be persuaded to commit professional suicide and resign?" "... all the wailing and gnashing of teeth ..." "... the stunt pulled ..." "... machinery that predict catastrophic levels of positive feedback ..." So Pielke sr. now famous statement that Watts "is devoted to the highest level of scientific robustness" stands on firm ground – not. Now back to the Trenberth, Fasullo and Abraham?
  15. Are you a genuine skeptic or a climate denier?
    472, Dana69,
    Earth’s atmosphere is such a “complex system”. Therefore analysis in detail, leading to meaningful forecasts or projections, is fundamentally impossible in principle.
    This is wrong. The butterfly effect is applicable to weather, not climate. It is probably not possible to accurately predict weather beyond a few days in advance, but climate is a hundreds-years-long average. Your argument is equivalent to saying that the movements of water in the ocean are so complex that it is impossible to predict the timing and height of the tides.
    ...atmosphere does not drive “climate change”...
    This is false, or at best misleading. Atmosphere by itself does not drive climate change, but it is a major factor. Attempting to imply otherwise is a blatant act of denial.
    If you think I simply spout this in an attempt to deny the obvious...
    Actually, yes, I do, because while you include selected facts, they are a miniscule representation of the bigger picture. To imply that plate tectonics and only plate tectonics controls climate is utterly absurd, simplistic, and, yes, a clear effort to spout in an attempt to deny the obvious.
    Moderator Response: Everybody, please move this conversation to the thread "Climate is chaotic and cannot be predicted." Thanks.
  16. Hockey stick is broken
    CB, By localized, do you mean NH only? Because no significant difference has beenestablished between the NH temperatures then and today. I agree that some proxies have been used to misrepresent the data.
  17. Trenberth, Fasullo, and Abraham Respond to Spencer and Braswell
    I conduct a study of a new cancer causing medicine. I have twelve subjects. I limit my report to the 3 least afflicted and the 3 most afflicted. The three least afflicted got better, but they were expected to do so anyway through normal treatment. The three worst afflicted all died, but they were so far gone that no drug would have saved them. The six middle patients were all greatly improved by the drug, but I don't report that. My analysis, limited to the three best and worst cases, clearly shows that the drug is ineffective and further research into it should be halted. That's good science for you.
  18. Are you a genuine skeptic or a climate denier?
    Dana69, if what you were saying were true then we would have to conclude that it is absolutely impossible to predict that Winter will usually be colder than Summer. I don't think that really holds up.
  19. Trenberth, Fasullo, and Abraham Respond to Spencer and Braswell
    @Phil M: WUWT's problem there is that they just didn't understand the paper and got it completely wrong. Allan's paper doesn't say anything about modern day feedbacks. It doesn't support Spencer & Lindzen's assertions in the slightest and it looks like a decent paper. There are no errors found in it yet, unlike LC09 and SB11.
  20. One-Sided 'Skepticism'
    No, Shub. Ad hominem has been well-explained above and on other threads. The case you point to would, if demonstrably unreasonable, simply be a form of non sequitur or post hoc ergo propter hoc.
  21. Are you a genuine skeptic or a climate denier?
    If you base your philosophy on that premise, that nothing can be meaningfully modeled, then I expect you to stick with it. Any further claim from you about the future will be taken as hypocritical. I'm joking. I don't think you meant to adhere strongly to L & M, but then why even mention it? Scientists know the climate is complex. They know that every actual system is complex and inter-related. Still, to the extent that physical laws are established, so too are established patterns of interaction. Vaunted? Do you really want to go down that road? I have made no assumptions about your attitudes toward anything, Dana69. Indeed, where I was unsure about your understanding, I asked questions. You have been given the chance to interact in a reasonable manner, whether to put forward your case against AGW and thereby, to some extent, establish your position (with all the attendant ideological implications) or to explore the science through open and objective (to the extent possible) dialogue. The use of "vaunted" suggests condescension, and condescension is the surest way to non-violently end a relationship. I'll accept evidence if you want to argue the basis of such condescension, but I won't descend into an insult-fest.
  22. Hockey stick is broken
    Jonathon, the issue Chris discussed was the misuse of a small area proxy to falsely claim a global trend. This does not suggest that proxies are unreliable... just that some people will misrepresent them. That said, the tree ring divergence problem of the past century does show an example of proxy results being unreliable. However, when you get matching temperature proxy results from glaciers, stalagmites, rock boreholes, tree rings, and many other sources it becomes very difficult to argue that they ALL experienced some effect OTHER than temperature which caused matching variations. Which is one of many reasons that the original Mann 1998 finding that the MWP was a localized effect with global temperatures significantly lower then current is now considered far more strongly established than it was then.
  23. Trenberth, Fasullo, and Abraham Respond to Spencer and Braswell
    @Phil M The abstract for Richard P Allan's paper says, "The cloud radiative cooling effect through reflection of short wave radiation dominates over the long wave heating effect, resulting in a net cooling of the climate system..." . Isn't that what we had always thought, as it's the basis of the long-standing proposal -- about to be tested -- that geo-engineered clouds will help cool the atmosphere. I'm struggling to understand why this should lead to anyone making exaggerated claims about 'nails in the coffin of AGW' and other such comments floating around the denialosphere.
  24. Hockey stick is broken
    Chris, I think you have highlighted one of the difficulties in using proxy data. Roh234 showed that even recent proxies can result in opposite conclusions. Consequently, some scientific organizations have backed away from claiming that recent temperatures are higher / lower than those during the MWP.
    Response:

    [DB] "some scientific organizations have backed away from claiming that recent temperatures are higher / lower than those during the MWP"

    Kindly please support that assertion with links; thanks!

  25. Chasing Pielke's Goodyear Blimp
    Make it rhyme? Christy's Twisties? Or if you want more accurate, Christy's Sophistry?
  26. Positive feedback means runaway warming
    jpat#91: "resampled the data to a 5 year interval using standard interpolation" There's a problem: Standard interpolation or not, you can't claim higher temporal resolution in processed data than you have in the raw data (you can claim higher SNR; that's the point of processing). But to say you've squeezed out 5 year resolution from irregularly sampled ice cores is akin to creating something (supposed information) from nothing (gaps in the original data). At the very least, you should filter the sampled data back below the aliasing frequency of the original and then realize you might not be fully imaging these hundred year lags.
  27. Hockey stick is broken
    Roh234 (@ 87) shows how easy it is for those that wish to misrepresent the science to pick-n-choose stuff that seems to support their misrepresentations. He shows a graph from Keigwin (1996). This data set refers specifically to a location in the Sargasso sea. If one was to address this particular data set scientifically, one would likely conclude that it was consistent with the evidence that the temperature variations during MWP (and to a lesser extent) during the LIA, were significantly related to ocean current and wind transport regime changes (solar driven?) that changed the distribution of global heat, with a large contribution involving “Gulf Stream” heat transport to the high Northern latitudes. It’s not surprising that temperatures in the Sargasso sea are sensitive to these. In support of this interpretation Keigwin and Pickart (1999) have shown that if one samples historical temperatures from cored proxies in the Laurentian Fan area to the NW of the Bermuda Rise, Sargasso Sea data, that sea surface temperatures were apparently much colder during the MWP compared to the LIA, and the temperatures of the Bermuda Rise-Laurentian Fan vary in “antiphase” as current regimes change. So if Roh234 (or the people that construct and disseminate misrepresentations) were to have selected Keigwin and Pickart (1999) rather than Keigwin (1996) he would have come to the opposite conclusion. Interestingly, Monckton uses the Keigwin 1996 graph to pursue exactly the same misrepresentation which is perhaps testament to the inherent laziness of those that consider it useful to attempt to pull the wool over our eyes!
  28. Positive feedback means runaway warming
    jpat, You should also consider that heat is not distributed evenly across the planet. A mean global temperature change of ∆T may be conceptually divided into at least 7 separate values by latitude (although the actual system is continuous in nature): equatorial, and NH and SH values for sub-tropical, temperate, and polar. These changes are non-linear (for instance, warming now is much greater at the equator than the south pole, and much greater at the north pole than the equator. As already explained, the strength of the effects of such temperature changes on feedback factors (ice, vegetation, ocean dynamics) vary by latitude as well, so now for each latitude you have a different ∆T, a different area, a different potential for impact (due to area, amount of insolation, and angle of incidence of the sun) and so an entirely different feedback value dependent upon absolute temperature and latitude.
  29. Positive feedback means runaway warming
    jpat, You are currently paralyzed by (a) restricting your thinking to circuit design and (b) trying to oversimplify the system. In particular, you need multiple feedback loops (short term CO2, long term CO2, H2O, low equatorial clouds, low NH clouds, high clouds, ice, CH4, etc.) which all interact with each other, some in non-linear ways, and with clock cycles that introduce varying delays. They are also bounded in unexpected ways. For example, the extent of ice cover can only advance and retreat so far, and ice further south is much more powerful since it covers a larger area, winter daylight hours are longer, and the sun strikes at a stronger angle of incidence. So the forcing-feedback effect Fice of the retreat of ice ∆I in response to a positive temperature change ∆T is also dependent on the actual ice extent I at the time of the change combined with the orbital configuration Xorbit. The ice extent I is itself dependent not only on temperature but also the current orbital configuration Xorbit. Fice is also moderated by the amount of low NH clouds Clow NH and aerosols A (since both of these block light and thereby negate any effects of ice on the surface). That's just a simplified set up for ice. The effects of CO2 and H2O are similarly complexly moderated (ice, aerosols and low clouds reflect visible light, resulting in less IR to feed the greenhouse effect, for example). The feedback loop for H2O is far, far faster than that for CO2. The different mechanisms for changing CO2 in the atmosphere (vegetation growth, vegetation decay, temperature-dependent ocean absorption/out-gassing, the very important biological pump, etc.) all work at different rates. In addition, the growth and decay of vegetation, like ice, is dependent on latitude... lower latitudes have more area, and are more hospitable to plant growth, so the initial effects of the retreat of the ice sheets on CO2 changes related to vegetation are far greater at lower latitudes than later retreat further north. The biological pump which is thought to cause the most abrupt and important changes in atmospheric CO2 in transitions between glacials and interglacials is, like all other factors in the system, bounded, non-linear and self-limiting. The entire system is just far, far, far more complicated than you are considering right now. A mechanic who tries to model the system in terms of an accelerator pedal, fuel line, fuel pump, etc. would have a better chance of producing an accurate analog of the system than an electrical engineer. I said it before: hammer/nail syndrome You are very strongly advised to stop trying to translate everything into your chosen profession and perspective, and instead to learn the science as it stands. You will be eternally stalled if you keep trying to hammer 27 round climate pegs into one, square EE hole.
  30. Chasing Pielke's Goodyear Blimp
    adelay: And, to be clear, I am talking about conversation that we are having in the present moment, not about conversation that we might think of happening at some time under some special conditions ... And I don't like the term because it offends me, not because it offends Christy. To first approximation, I don't really care what offends Christy.
  31. Are you a genuine skeptic or a climate denier?
    [inflamatory deleted] In 1960 Edward Lorenz asked, “Does the Earth have a climate? The answer, at first glance obvious, improves on acquaintance.” About 1975 Benoit Mandelbrot expanded on Lorenz’s Chaos Theory –positing a “butterfly effect” with “strange attractors” etc.– by formulating Fractal Geometry, a depiction of natural reality as non-random but strictly indeterminate, self-similar on every scale. Together, Lorenz and Mandelbrot determined that extrapolating phenomena of suitably complex systems (those where three or more variables interact) is mathematically as well as physically impossible. Earth’s atmosphere is such a “complex system”. Therefore analysis in detail, leading to meaningful forecasts or projections, is fundamentally impossible in principle. Climatologists adducing ambiguous historical data, necessarily incomplete and inconsistent, to plot not merely local but global temperatures decades in advance are either [deleted at posters' request] As Lorenz suspected, atmosphere does not drive “climate change”. From 1964, geophysicists have known that plate tectonics, Alfred Wegener’s “continental drift” hypothesized in 1912, constantly reconfigures continental dispositions on geologic time-scales. Cyclical Pleistocene glaciations began when North and South America walled off Earth’s eastern and western hemispheres, blocking circulation of deep-ocean (bathymetric) currents, regularly resetting global thermostats. This phenomenon will only end 12 – 15 million years from now, when hemispheric landmasses shift sufficiently to re-establish oceanic circulation patterns. Basic physics, whereby evaporating hot air rises to draw cooler northern currents underneath, cites convection currents rather than any micro-pollutant as symptom, not cause, of long-term cyclical “climatic” shifts. Precipitation becomes key– flooding rains in summer, blizzard snows in winter. “Weather”, yes, but inextricably a part of Lorenz’s and Mandelbrot’s “complex system". If you think I simply spout this in an attempt to deny the obvious, please feel free to check out your own vaunted IPCC report that agree with the same. 14.2.2 Predictability in a Chaotic System "The climate system is particularly challenging since it is known that components in the system are inherently chaotic; there are feedbacks that could potentially switch sign, and there are central processes that affect the system in a complicated, non-linear manner." http://www.ipcc.ch/ipccreports/tar/wg1/504.htm [inflamatory deleted]
    Moderator Response: [Dikran Marsupial] Please read the comments policy, inflamatory comments are unhelpful. The weather is chaotic, however the climate (long term statistical behaviour of the weather) probably isn't. Non-linear does not mean "unpredictable". [Somebody else] Also please read the post "Climate is chaotic and cannot be predicted" and comment further there, not here.
  32. Hockey stick is broken
    Eric, as I explained in comment #90 above (and as can be clearly seen in Ro234's first graph), McIntyre's 'alternative' tree ring data series diverge from reality over recent decades. So the question is... why should Briffa have sought out and incorporated erroneous data? McIntyre is here not disputing the 'stick' but rather the 'blade'... the recent large upward turn. Yet that is established not only by selection of ACCURATE tree ring proxies, but by numerous other proxies (see the main post above)... and actual surface temperature measurements... and satellite readings... and ice loss... and species migration... and... The planet has NOT experienced a massive drop in temperatures since the 1950s. So McIntyre's argument that Briffa should have shown that it had is pure nonsense. He's accusing Briffa of malfeasance for showing CORRECT results.
  33. Hockey stick is broken
    The thread of the argument in the top post is a little disorganised. The skeptical point at the top begins "In 2003 Professor McKitrick teamed with a Canadian engineer, Steve McIntyre, in attempting to replicate the hockey stick and debunked it as statistical nonsense...." M&M03 doesn't get discussed at all in the article proper, which is a bit of an oversight I think. Also, McIntyre 2004 (?) is referenced, but the paper linked is actually McIntyre & McKitrick 2005.
  34. Trenberth, Fasullo, and Abraham Respond to Spencer and Braswell
    Over on WUWT, I notice how they love to exagerate the scientific position so that it's always "catastrophic" & "CAGW". "Spencer and Braswell plus Lindzen and Choi, it throws a huge monkey wrench in climate model machinery that predict catastrophic levels of positive feedback enhanced global warming due to increased CO2." http://wattsupwiththat.com/2011/09/20/new-peer-reviewed-paper-clouds-have-large-negative-feedback-cooling-effect-on-earths-radiation-budget/ If you start at that point, anything less than catastrophic or apocalyptic means the conned can declare it was all overhyped.Classic strawman.
  35. Positive feedback means runaway warming
    Just to note: circuit theory is a particular case of network theory. Azimuth is the home of mathematicians who's are a bit good at the former and interested in climate science... The series on network theory have plenty, classical, feed back loop models which do not run away. If someone was really interested, they might ask there to analyse this.
  36. Trenberth, Fasullo, and Abraham Respond to Spencer and Braswell
    Spencer & Braswell's model choices were very suspicious. Why didn't they compare 10 year model runs with 10 year observations to get an apples-to-apples comparison. Why didn't the reviewers pick up on this obvious dodgy choice and the lack of quantified errors? Did they run the models and get the same results as Trenberth et al? If so, why did they choose the 6 they did? They had a reason (3 most/3 least sensitive), but if I was doing the analysis and I noticed that some of the models (e.g. ECHAM5) did quite well, then I would wonder why and publish them. Did SB automate the analysis without checking the fit of the models to data (so their scripts would just return 3 most/3 least sensitive), or did they see this, decide they didn't like it and hide the data? Lindzen & Choi was similarly suspicious. They used a subjective method to pick time periods for analysis, just HAPPENED to pick periods which gave a low sensitivity and apparently 'forgot' to test the sensitivity of their model to find out it was mostly useless. Pretty large blunders that, if honestly made, you'd hope the scientists would own up to and correct.
  37. Chasing Pielke's Goodyear Blimp
    Chemware, #89: Yes, it is ridicule. And it is appropriate, because what these guys are doing is ridiculous: science in bad faith. Bern, #97: Wanting to avoid offending our own readers, or potentially new readers, is not at all equivalent to letting the self-described skeptics frame the issue. It's a free way to expand mind-share. adelady, #100: If you're not offended by the word "crock", that just means you aren't one of the people who are offended by that term. I am. I'm sure that if we sat down around a dictionary, there would be terms that don't offend me but do offend you; in that case, it would be polite for me to avoid using these terms in conversation with you, to the extent possible without encumbering the communication. Don't you think so?
  38. Chasing Pielke's Goodyear Blimp
    Surely if SkS had a blog list on a side panel, beneath or opposite the Christy Crocks button there'd be a link to 'Climate Denial Crock of the Week'. I really don't understand the fuss.
  39. Chasing Pielke's Goodyear Blimp
    Why chase the blimp? Because it's a very interesting and fascinating blimp (hence such an effective diversionary tactic). There are lots of engrossing questions there worth exploring. But before doing so, I just wanted to remind people of what this conversation was about in the first place.
  40. Chasing Pielke's Goodyear Blimp
    Why chase Pielke's Goodyear Blimp or respond to his diversionary tactics at all? Is anyone being a tad oversensitive?
  41. Positive feedback means runaway warming
    jpat - I dont know electrical circuits but one obvious thing you need is a second feedback circuit (albedo is of similar magnitude but much faster response). Second, can you build one so that feedback response is different when temperature is rising than when it is falling?
  42. Chasing Pielke's Goodyear Blimp
    It's an interesting discussion here. I'm left with two thoughts: Perhaps the badge "Christy's Crocks" should be changed, to something like "Christy's Confusions", to avoid offending those who only know of one association for the word "Crock". However, that immediately leads me to my second thought: At what point do we draw the line, and stop letting the self-described "sceptics" control the framing of the discussion? It's a tough question to answer. On the one hand, being polite and analytical, not emotional, is what scientists are trained to do in their communication (some have more success at achieving this goal than others). On the other hand, as the interview interrogation of David Karoly by Alan Jones showed, that approach doesn't work so well in the world of the 'sceptical' media. Similarly, if it's a message for the general public, and you have one person speaking in a calm, scholarly tone about data, models, and probabilities, while another person is jumping up and down, frothing at the mouth, screaming about economic ruin and "condemning billions to a CO2 death"... well, you know, if the media themselves don't act like journalists and expose those claims for what they really are, perhaps the real sceptics need to?
  43. Climate Communication: Making Science Heard and Understood
    The communication problem is that rational argument frequently does not succeed in changing peoples' minds. This excellent site provides the rational argument, but do not for a moment think that its words will affect entrenched ideas. We need to woo people, not bludgeon them with facts. See the interesting article "How Facts Backfire" at http://www.boston.com/bostonglobe/ideas/articles/2010/07/11/how_facts_backfire/
    Response:

    [DB] Hot-linked URL.

  44. One-Sided 'Skepticism'
    Philip You state: "Saying that Spencer and Christy are "somewhat infamous" as the guys who claimed their data invalidated global warming until others corrected their errors is a mere statement of fact. They did that and are known for it. That is a simple fact." Merely calling Spencer and Christy 'infamous' is not an ad-hominem argument. Implying that there may be cool biases in the UAH record due to the prior infamous history of errors in the UAH record, is, an ad-hominem argument. The Sept 14 article makes such an ad-hominem argument. The article above states: "He [Pielke Sr] seems to think Christy Crocks and Spencer Slip Ups pertain to satellite temperature data analysis: ... Unfortunately for this piercing critique, these two series of articles do not touch upon the topic of the satellite temperature data. Indeed, the only time SkS has mentioned this work was when we used it as an example of the self-correcting nature of the scientific process." Clearly, all the above claims are refuted.
  45. Just Put the Model Down, Roy
    I wish I would have read comment 57 before posting 58.
  46. Just Put the Model Down, Roy
    @Rob Honeycutt >> I would be very interesting to use Roy's model to produce a "paper" showing extremely high climate sensitivity and publish it in the same journal this one was published. Right. Perhaps adjust the main equation a little if necessary. Then start the show by producing a new set of parameters that lead to similar predictions 100 years out after matching current data. [At this point "skeptics" will be jumping in their seats.] Then get a new set of parameters that lead to 200 deg C increase instead. Finally, wrap up with yet another set of values that predicts 200 deg C decrease despite overlapping with current satellite data. The point of the exercise would be to demonstrate to the layperson that we can construct a complex curve to resemble, in close-up range, any simpler curve (such as a simpler curve approximating satellite data of a certain time period). [Ask a mathematician to state a proper theorem and quantify it more accurately.] Intuitively, what is happening is that some parts of the complex formula look like the simpler curve while other parts of the complex formula cancel out or are close to zero during the particular close-up region. These parts that disappear during that region then kick in as we move away. A physical hypothetical example would be that some very high "positive feedbacks" are dormant until some level of its independent variables (eg, some particular gas level in the atmosphere or some temperature value) are triggered or until "exponential" growth "kicks in" at the resolution we are looking at. Another intuitive explanation is that we can trace over whatever simple curve we want and then draw out the rest of the curve into the future however we feel like it. This technique is sometimes also described this way "add your favorite data points next to satellite data points and let your 5 year old child connect the dots".
  47. Positive feedback means runaway warming
    The lag between a positive temperature forcing and CO2 coming out of the oceans is relatively large, due to slow ocean circulation. Once the CO2 gets into the atmosphere, it operates immediately as a forcing on climate. In your electical system above, it gets there via the slow feedback, and so there would be a delay between the temperature change (which has to rise first) and the CO2 (which amplifies the temperature change, but rises later). Now consider what happens if you release a very large amount of CO2 directly into the atmosphere. We've done that, adding more that the entire CO2 difference between LGM and Holocene within about 100 years. Does the CO2 wait patiently for 800 years before operating? No, it starts working as soon as a suitable packet of longwave radiation passes by! How will your graph look now? Will there be much of a lag between temperature response and CO2? Which one will rise first, all other factors excluded?
  48. Positive feedback means runaway warming
    We seem to be talking past each other so let me try one more time to illustrate the difficulty I'm having. Consider the following toy model of the climate. Forcing function F drives the input. It gets summed with the feedback signal and converted to temperature by Gain2. The feed back path encapsulates the functional relationship between Co2 and temperature. The transfer function models the time lag between a change in temperature and the corresponding change in CO2 concentration at node C. Gain1 handles the conversion from CO2 to radiant energy. The feedback is positive but low enough that the system is stable. The paleo temperature record corresponds to the signal at T, the CO2 record to the signal at C. We ask ourselves, what is the expected time relation between T and C under closed loop conditions? Answer: Same as under open loop conditions! I.e. feedback can not change the open-loop relationship between T and C. If the physical mechanism that produces CO2 when the temperature rises includes a lag (and it does), we expect to see that same lag under closed loop conditions. How can it be otherwise? The relationship between T and C is defined by the blocks between them. And note that relationship is completely independent of the complexity of the transfer function which could include other internal feedback loops, other gain paths etc. I can think of no system formulation that could possible convert a lagging signal to a leading signal. I hope this clears up my conundrum.
    Response:

    [DB] Since you are fond of analogies, let me share this one with you: 

    Your conundrum, distilled, is that you are treating climate science as some that learn a foreign language:  you are insisting upon translating the words you hear into English before assembling them into sentences.  However, to truly learn a foreign language, one must learn enough vocabulary, sentence structure and syntax to understand the foreign language in your head without the need for translation.  In essence, you need to be able to think in that foreign language before true understanding of it is then reached.

    That is what is retarding your understanding.  As it has retarded the understanding of electrical engineer-types like RW1 and co2isnotevil before you.

  49. Positive feedback means runaway warming
    I think this point has laready been made, but jpat, you seem to be desiring a single, simple function to explain palaeoclimate and feedbacks. Except... climate variations depend on a series of interrelated systems, each operating at different rates, with different magnitdes at different phases of the climate history. Stephen Baines describes some of that complexity. As climate is forced into a cooling, we get ice sheet expansion over North America and northern Europe, increasing the albedo effect, and having knock-on effects for temperature, water vapour, biomass, CO2, sea ice and a whole lot of other things, each operating at a different rate, with different lags, and feeding back to temperature and drawing down a little more CO2. The process is self-limiting, because eventually the ice can't grow enough for albedo to overcome mid-latitude insolation and the forcings don't remain permanently low, and so with the present continental configuration, high-latitude glaciation is easy, but global glaciation is not so easy. Once it's in place, you need a sufficient forcing to drive the system in the other direction. When the forcing operates in the other direction, the now kilometres-thick ice sheets over North America and N Europe begin to melt, and can do so quite rapidly due to dynamical processes, especially when the height of the ice sheet begins to drop. That aids all the other feedbacks operating in a warming direction, but there is an element of self-limiting as eventually the big ice sheets have shrunk and so the albedo component can't drop quite so fast, and the forcing is no longer at a maximum. In order to continue the melting into the next vulnerable ice sheets - Greenland and West antarctica - you need an extra forcing kick. CO2 can operate as a forcing or a feedback (the molecules have no memory of how they got into the atmosphere, they just trap heat), and by releasing lots of CO2, we've provided the extra kick in forcing, which means that Arctic sea ice, Greenland and West Antarctica are vulnerable. There's nothing magical about why most interglacials appear to have approximately similar magnitudes, as that is a function of continental configuration and the length of the forcing. During the last interglacial, it's likely that parts of Greenland and West Antarctica melted as well. That's a very long way of saying that you cannot easily represent the full interrelationships of forcings and feedbacks with a simple function. In fact, the best way to capture the relationship is to build a model of all the relationships (a simple function is merely a simple model after all), incorporating all the radiative physics as best we can. You'll get even better results if your model is a spatial one that can capture trickier concepts like continental configurations and ocean circulations. This has been done, they are called GCMs. You didn't seriously think that the experts in this field who have worked on this for their whole careers hadn't thought of all this? You can't come at climate science from an unrelated field and completely grasp all the complexities without a great deal of effort. You seemed to be suggesting that you can, if your misconceptions about the palaeo record & CO2 and how much it's all 'figured out' in #58 and elsewhere are anything to go by. I can only recommend you re-read Sphaerica's advice in #51.
  50. Debunking Climate Myths from Politicians
    Oh, but the earth HAS been warmer than now. In Pliocene, there was no glacial cycle and much still in more distant past. Probably warmer in the HCO as well in much more recent history but that was due to sun.

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