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All IPCC definitions taken from Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Annex I, Glossary, pp. 941-954. Cambridge University Press.

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Comments 86901 to 86950:

  1. Chip Knappenberger at 01:33 AM on 4 May 2011
    Frauenfeld, Knappenberger, and Michaels 2011: Obsolescence by Design?
    skywatcher@87, Perhaps I am missing something here. You and Dikran are suggesting that the negative melt anomalies in the late 70s/early 80s are the result of positive anthropogenic climate forcings? Or that they are not really negative anomalies, but rather represent the mean climate state at the time? Or perhaps even that the natural state was trending downward and then anthropogenic positive forcing stopped that downward trend and turned it positive? I guess all of these things are possibilities that would invalidate my conclusion. It is just, that in my opinion, I don't ascribe to any of them...but, admittedly, I could be wrong. -Chip
  2. Frauenfeld, Knappenberger, and Michaels 2011: Obsolescence by Design?
    In addition to Dikran's point, #84, the appeal to 'naural variability' does not stand up. There has to be a process driving that change - presumably you (FKM) envisage that process reversing? What forced the variability, and why would melt be at all likely to return to some 'natural' base level given the well-understood climatic forcings in place at present?
  3. Rob Honeycutt at 01:19 AM on 4 May 2011
    Frauenfeld, Knappenberger, and Michaels 2011: Obsolescence by Design?
    Chip @ 58... Your response is not very compelling to me for a couple of reasons. First, on an interpersonal level you're not responding to what I'm saying. You're merely speaking "at" me, not to me, and reposting things that I've already read. Second, your case is still not compelling, and is fact extremely concerning, in that you're essentially abdicating responsibility to get the research right. On one hand you're saying, "We didn't do the actual research" and then you're contradicting statements from one of the key people who DOES do the actual research. And those statements (from Dr Box) have been, obviously, quite forceful in their condemnation of the conclusions of FKM2011.
  4. Chip Knappenberger at 01:15 AM on 4 May 2011
    Frauenfeld, Knappenberger, and Michaels 2011: Obsolescence by Design?
    Dikran@84, I was referring to a return from the negative ice melt anomalies in the late 1970s/early 1980s. With or without anthopogenic forcing, natural variability still exists, and since there is the possibility that positive climate forcings from human activities is not what led to the negative ice melt anomalies in the late 70s/early 80s, then a non-anthopogenic-induced return from those anomalies should not be out of the question. Right? -Chip
  5. Dikran Marsupial at 01:04 AM on 4 May 2011
    Frauenfeld, Knappenberger, and Michaels 2011: Obsolescence by Design?
    Chip Knappenberger@82 There was signficant anthropogenic influence on the greenhouse effect in place in the late 1970s and early 80s (and decreasing negative forcing due to aerosols) so to use that as evidence that without positive forcing from AGW a return to the long term mean is a non-sequitur. Perhaps there is something missing from your post? There is no reason to expect a return to the long term mean according to mainstream climate science, which includes the CO2 being a greenhouse gas, climate sensitivity being of the order of a couple of degrees C per doubling and albedo feedback. All three of those suggest a return to the long term mean is unlikely.
  6. Lindzen Illusion #3 and Christy Crock #5: Opposing Climate Solutions
    Sphaerica at 00:17 AM on 4 May, 2011 I have noticed this "alarmism against mitigation" for some time now. Dan Moutal mentioned an interesting similar pattern by the time of the CFC problem: people claimed that prices of apliances would skyrocket, poor countries would be denied access to these conveniences, manufacturers would go bankrupt, and so on. Of course, the world survived the Montreal protocol quite well.
  7. Lindzen Illusion #3 and Christy Crock #5: Opposing Climate Solutions
    Bern, Alexandre, Absolutely, it is a simple concept at the highest level; it is more complicated as you get into the details. I concur on everything you said, FF industry, US indebtedness to China, US in historical view (nevermind when the world's hungry turn their baneful eyes from their own leaders to the US), etc. IMHO, it would be foolish for the US to try to strong-arm China. It is to be hoped that we have a rational leadership when talks resume. No, I would guess that China is not interested in a carbon tax. A tax is how governments steer a free market, and China's market is not as free as the US's. Any agreement would have to focus more on emissions reductions rather than the mechanism for how those reductions were achieved. Pity that CO2 satellite did not make it in to orbit. My main point is that, despite the rather un-democratic nature of it, it might be more effective to pursue an emissions agreement amongst the top few economies rather than pursue one that is acceptable to 100 or more at the start. At this point, I, personally, would accept a non-democratic solution over no solution.
  8. Chip Knappenberger at 00:57 AM on 4 May 2011
    Frauenfeld, Knappenberger, and Michaels 2011: Obsolescence by Design?
    The Skeptical Chymist, I am not sure that you have it quite right when it comes to our statistical tests. There are 20 years during our reconstructed period (1784-1978) in which the observed melt index for 2007 was contained within the 95% confidence bounds about the reconstructed value. So our “test” was on individual years, not a particular period. If this explanation doesn’t answer your question, then perhaps I am not understanding it correctly. As far as whether or not the current melt extent and trend are important or not, our point was that there seems to have been another extended period of positive melt anomalies across Greenland for several decades in the early/mid 20th century, and that period did not result in a large uptick in the rate of sea level rise (although there is some evidence that the rate of sea level rise did increase a bit during that period). This led us to conclude that if the current melt extent stayed somewhat equivalent to what it was back then, we wouldn’t expect a big jump in the rate of sea level rise as a result of cryospheric processes (surface melting and dynamic ice loss from glaciers). Clearly, if the melt (and other losses) where greater than back then, then so too will be the contribution from Greenland. 2007 and 2010 were years with a lot of melt. 2008 and 2009 were not. -Chip Knappenberger
  9. michael sweet at 00:54 AM on 4 May 2011
    Lindzen Illusion #3 and Christy Crock #5: Opposing Climate Solutions
    Ken, For only the most simple example: If energy costs go up 50% and I install more insulation so that my energy use goes down 60% I save money and have lower total bills. Your suggestion of bankruptcy is alarmism of the worst kind and is easily shown to be untrue. If I install a ground source heat pump I save money, even if energy costs go way up, and it expands the economy since I have to pay to have the heat pump manufactured installed.
  10. Chip Knappenberger at 00:37 AM on 4 May 2011
    Frauenfeld, Knappenberger, and Michaels 2011: Obsolescence by Design?
    Several commentors here seem to have taken issue with the idea that some of the positive trend in ice melt observed across Greenland from 1979-2010 could potentially have resulted from natural variability. The reason the results of our paper suggests this, to me at least, is that the ice melt in late 1970s and early 1980s (i.e. the early years of the satellite record) was considerably below the long-term average (or at least as we have reconstructed it). So, even without any positive forcing from a greenhouse effect being enhanced by anthropogenic influences, a return to the long-term mean (at some point) would seem a reasonable expectation. I doubt that the entirety of the trend in ice melt extent across Greenland from 1979-2010 results from natural variability, but it would seem a bit foolish to rule out the possibility of any contribution whatsoever, based upon our results. So, to me, the contribution is probably greater that zero and less than a 100%--so I am comfortable with my characterization that a “sizeable” portion “could potentially” be a result of natural variability. -Chip Knappenberger
  11. How climate change deniers led me to set up Skeptical Science website
    Albatross@54 I think that comments regarding the quality (or lack thereof) of other climate blogs are relevant and on topic for this thread. I became a regular (lurker) here because of SkS' quality of science and dialog when compared to places like WUWT. Ken Lambert@everywhere Please stop trying to derail this thread and take the discussion back where it belongs.
  12. The Skeptical Chymist at 00:24 AM on 4 May 2011
    Frauenfeld, Knappenberger, and Michaels 2011: Obsolescence by Design?
    Barry@77 Yes it is perfectly acceptable for a reviewer to submit a rebuttal of a paper which they reviewed but which they consider has major flaws. From reading Dr Box's blog it appears he is doing so. Regarding the authors statement that "one more year of data is not going to materially affect our analysis or conclusions" I agree with Albatross@61. The last few lines of a papers' abstract is where you put your "take home" message/ most important conclusions. It is very clear that including 2010 data would have required a rewrite to this section, because it would have altered their "take home" message. To state otherwise, as Chip and Co did, is simply incorrect. Otherwise if Chip@58 is still around I have a question or two as my uni (oddly enough) doesn't have an online subscription to JGR. 1) You tested whether the melt in 07 was sig diff to the melt between 1923-1961. Why did you test against 20 specific years, instead of the whole high melt period? 2) Why does your paper emphasis the duration of the historical high melt period vs present melting? Given that temperature increases in Greenland (and hence melting) are only just getting started, wouldn't the magnitude of the melting and trend of melting be more important? Or to rephrase, the current high melt is almost certain to last for longer than the previous, why is the fact that is hasn't (yet) particularly important?
  13. Frauenfeld, Knappenberger, and Michaels 2011: Obsolescence by Design?
    skywatcher wrote : "Aside from that, I feel Dr Box should have conducted the second review, and insisted on paper rejection as the changes had not been made. Had he done that, and the paper still been accepted, he would have a stronger case. But having not done that, he was not in a good position to cry foul that the paper got through." I'm not so sure about that - remember the kerfuffle over O'Donnellgate, with regard to the Antarctic ? It seems that there would be an outcry no matter where in the chain these criticisms are made, and if a paper is refused publication because of the involvment of someone whom the so-called skeptics could claim was censoring 'opposing' views...well, that would unleash a great wailing and gnashing of teeth in the Denialosphere !
  14. Bob Lacatena at 00:17 AM on 4 May 2011
    Lindzen Illusion #3 and Christy Crock #5: Opposing Climate Solutions
    16, Ken,
    Bankrupcy??
    This is alarmism of the worst kind, and the crux of the problem with those who fiercely resist the science and the solutions. This panicked fear that costs must be extreme, to the point of destroying economies, is absurd. First, no one is very easily going to give up comforts, let alone necessities. No one is going to sit idly by while all of civilization crumbles. That only happens when the economy spirals out of control through greed and mismanagement (see 1929, 1987, 2007). Second, a transition to alternate energy sources does not represent a net loss to society as a whole. The infrastructure of society is constantly being renewed. Nothing lasts. Manufacturing and transportation equipment, roads, rail lines, power lines, power plants, everything is constantly being maintained or replaced. So if we simply change what we use to replace the old... newer, better techniques using renewable energy sources rather than fossil fuels... there is no net loss to the economy. The loss is only to those who would profit from purely fossil fuel solutions. In the long run, there is a net gain for society. All economies benefit. In fact, the only losers will be those who desperately cling to the old, inefficient and uneconomical ways, as the smarter, more adaptable economies move forward and embrace change. Alarmism and panic are not helpful.
  15. How climate change deniers led me to set up Skeptical Science website
    Ken Lambert @64, while you have not made any significant errors of calculation, you have persistently made conceptual errors which if left uncorrected would result in errors in the final result of up to two orders of magnitude. You are equally persistent in never acknowledging these errors as errors, not matter how glaringly obvious they may be. Of these, my favourite examples are your rather arbitrary decision that the incoming flux for 90 days must really be the incoming flux for (approx) 10950 days, a view you returned to repeatedly and have never acknowledged as a mistake; and your decision that the average incoming flux over a 90 day period was the peak incoming flux over that period, and that consequently it needed to be divided by two to find the average. To cap the later of you then divided the result by two again apparently because the measured 2 million square kilometer reduction in sea ice did not fit your prejudice. Again, you have refused to acknowledge that that mistake was a mistake. All of this is of a piece with the original basis of discussion, your insistence that the low altitude of the sun in the arctic summer must raise ocean albedo so much that any calculation showing a strong positive feedback from loss of arctic sea ice can be rejected out of hand. In arguing for this, you never calculated the relevant values, but merely insisted the work of a number of scientists who had was flawed. Apparently the effect was so obvious it did not need calculation, and the scientists so stupid that they had missed it entirely in their calculations. The belief that you can rebut the scientists without making the calculations makes no sense without those two assumptions. I attempted to supply the calculations for you - making sure to bias the results in favour of your arguments. Unfortunately I made a number of trivial errors which needed to be tracked down and corrected. Now that they have been tracked down and corrected, they clearly show your original assumptions about the magnitude of the effect where mistaken. Rather than acknowledge your error, you have launched a major attempt to disrupt this thread - and changed the subject on the Flanner thread. You have certainly not, or course, acknowledged your error. I have resisted pandering to your attempts to derail this thread until now. Rather, I responded on the appropriate thread. Rather than filling this thread up with your false claims, perhaps you also can keep the discussion where it belongs.
  16. Frauenfeld, Knappenberger, and Michaels 2011: Obsolescence by Design?
    Seems to me there are several issues that come out - 1: statistical significance of the recent years in relation to past years according to the model. Whether or not they are technically correct is actually less of an issue than their avoidance of the modern trajectory of change. It's quite disingenuous to talk of that trajectory earlier in the paper, yet leave it out of the conclusions. 2: Avoidance of the issue of mass loss versus surface melt - mass loss includes ice loss through calving, which has accelerated since the mid-20th Century. Surface melt is not necessarily therefore a good proxy for sea level rise resulting from Greenland. Both the above points allow two of the authors, as noted by others above, to falsely suggests that 'there's nothing to see here' in Greenland, despite all the evidence of accelerating mass loss described by Daniel Bailey. 3: The review process. I have to say I agree with barry here - I don't like the airing of private reviewer comments such as has happened here. That does not seem to me to be good academic discourse. Aside from that, I feel Dr Box should have conducted the second review, and insisted on paper rejection as the changes had not been made. Had he done that, and the paper still been accepted, he would have a stronger case. But having not done that, he was not in a good position to cry foul that the paper got through. That the other (anonymous) reviewer gave the paper a free pass as far as can be seen, is perhaps more of an issue, but the natural process of academic discourse should be allowed to progress - ie that relevant academics submit responses critiquing the paper. Given how (deliberately) poorly-written the conclusions are, and that it is already out-of-date, I suspect this will happen.
  17. Ken Lambert at 23:30 PM on 3 May 2011
    Lindzen Illusion #3 and Christy Crock #5: Opposing Climate Solutions
    "It's important to distinguish between prices and bills – an increase in the former doesn't necessarily cause an increase in the latter, if other measures are taken to prevent bills from rising." And in a competitive economy what measures would those be? Bankrupcy??
  18. Waste heat vs greenhouse warming
    RSVP - I considered providing a detailed response to your last posting. The thing is, I would just be repeating what I and other posters have said, over and over and ... (repeat as desired). I believe, instead, that I'll just leave that as a coda to this discussion. You've consistently displayed what I consider a cardinal sin of intellect - You have failed to learn in the face of obvious errors in your thinking. You're locked into your opinion, come Hades or high water. Your opinion holds proof against both quantitative and qualitative evidence to the contrary. There's nothing I can do about that - a rational discussion seems impossible. I believe readers can peruse this thread and come to their own conclusions based on what has been presented. Finis.
  19. Dikran Marsupial at 23:07 PM on 3 May 2011
    Frauenfeld, Knappenberger, and Michaels 2011: Obsolescence by Design?
    chris@79 Until I got to the bit that said "I have a feeling you are arguing for the sake of it somewhat (or seeing who can raise pedantry to its most extreme level - you might be inching ahead now!).", I was going to reply to your post, but I see little point if you can't conduct a scientific discussion in a civil manner. Especially after calling my interpretation of the review "silly" because I based in on words Box had actually used. No, I haven't been engaging in pedantry, merely stating my opinion on Box's review and correcting a few errors in your responses. As it happens the statement that you object to in the abstract, seems fine to me. Yes, it is uninteresting, but I am in favour of papers that place bounds on the strength of conclusions that can be drawn. Unless you can identify a methodological flaw in the statistical test that supports that statement, then there is nothing wrong with it. Unless you can behave in a more scientific manner, that is the end of the discussion for me. P.S. No problem about the "Dikram", it is not my real name anyway.
  20. Ken Lambert at 22:43 PM on 3 May 2011
    How climate change deniers led me to set up Skeptical Science website
    Daniel Bailey #59 I must be in a parallel universe. Daniel - there was no error, no retreat and diversion escape plan - no Black Knight. I invite all SKS readers to the "Flanner" thread and ask any one of them to point out my errors. Your comment is such a breathtaking distortion of the facts that I am frankly shocked at the attempt.
  21. Frauenfeld, Knappenberger, and Michaels 2011: Obsolescence by Design?
    Has anyone done the numbers to determine if the idea that, "...waiting for one more year of data is not going to materially affect our analysis or conclusions. While the melt across Greenland has been elevated for the past 10 to 15 years (and continues in 2010), this period of time is still only about half as long in duration as the elevated (reconstructed) melt across Greenland from the 1920s through the early 1960s. So the addition of one more year of melt data (i.e., 2010), will not impact this comparison.” ? I'm not sure that Dr Box's comments hit on that specifically - but i'm a layman and might be reading things improperly. From what I've learned of the review process, disclosing review comments, the identity of reviewers (even if oneself) and the editor immediately after a paper has been published, especially in an effort to rebut the paper, undermines the process. When skeptics disagree with a study/theory/conclusions/methodologies, we encourage them to do some work and submit. Dr Box, of course, is in the perfect position to do this. I'm not sure if submitting a direct rebuttal is kosher for a reviewer of a paper, but if so, that avenue is wide open to Dr Box. Disseminating information that is meant to be confidential in a blog (or series of) is not meritiricious, no matter the reason. Dr Box may or may not be right here (I don't know), but it seems to me we've sidled towards the contrarian's way of doing things. Signed - regular follower and great appreciator of skepticalscience.
  22. muoncounter at 22:38 PM on 3 May 2011
    Could global warming be caused by natural cycles?
    RW1#182: "if the trend amount is less than the amount of observed variation over the trend, it's not outside the range of natural variability." The question was (and still is): what exactly is that range of natural variability? Until you provide said range, together with a documented analysis of how its derived, you have no business making any such claims. scaddenp#187: "Does winter wipe out a whole summer of warming?" This appears to be an echo of prior comments.
  23. How climate change deniers led me to set up Skeptical Science website
    Perhaps, johnd, you should read THE AUSTRALIAN more closely, especially the National Affairs section : Monckton's back: Christopher Monckton is returning to Australia in July to warn about the threat of the carbon tax. May 02, 2011 7:41AM Haven't read about that on SkS yet...
  24. Could global warming be caused by natural cycles?
    johnd wrote : "The El-Nino Index is still in negative territory, about -1, and though it is weakening slightly, it is expected to strengthen again and remain negative well into 2012." Where are you getting your information from, concerning the prediction into 2012 ? The latest NOAA ENSO Cycle: Recent Evolution, Current Status and Predictions states : A transition to ENSO-neutral conditions is expected by June 2011
    Moderator Response: [muoncounter] fixed link
  25. Frauenfeld, Knappenberger, and Michaels 2011: Obsolescence by Design?
    apologies, I shouldn't call you Dikram when your name is clearly Dikran...my bad
  26. Frauenfeld, Knappenberger, and Michaels 2011: Obsolescence by Design?
    Exactly Dikram... it doesn't tell you anything interesting.. it's obvious really. And yet the abstract of the paper we're discussing contains the sentence: ”The greatest melt extent over the last 2 1/4 centuries occurred in 2007; however, this value is not statistically significantly different from the reconstructed melt extent during 20 other melt seasons, primarily during 1923–1961.” Call me picky, but apart from the falsehood of the sentence about greatest melt extent, the sentence contains a statement that I think we both agree doesn't tell you anything interesting. My point, which I keep banging on about (and I believe we both agree on) is that a reviewer might be expected to pick up on that. That sentence simply shouldn't be there. I have a feeling you are arguing for the sake of it somewhat (or seeing who can raise pedantry to its most extreme level - you might be inching ahead now!). The point about the Douglass analysis is that it was an inappropriate test of the comparison of empirical and model data to assess whether models could be invalidated (shown to be inconsistent with...) on the basis of some statistical analysis of uncertainty associated with the empirical data. They did it to attempt to pursue a misrepresentation most likely. I'd say that is a "pseudo" analysis. A pedant might disagree! But since I've hopefully made clear exactly what I mean when I use the prefix "pseudo" in this context, there really shouldn't be cause to quibble, should there? It's very important in science to try to convey clear what one means. Would that reviewer's of papers would be so careful...
  27. Lindzen Illusion #3 and Christy Crock #5: Opposing Climate Solutions
    Chris G, Bern China's economy is growing fast, and so are its emissions. But unlike the US, they're investing heavily in renewables too. The US is being held hostage of FF lobbyists. It's perhaps an important weak point of their democracy, and it's making them lead the world's denialism and delayed action. Which is ironic, given the fact that a lot of the climate science, research and monitoring is US made. China does not seem interested in a carbon tax, AFAIK. They're doing the transition from a central command, just because the government saw it strategically fit. The US and EU, as large consumers, could impose efficency and environmental standards to exporters. This could be a big impulse for cleaner practices. The carbon tax could play an important role here, making these cleaner energy and goods more attractive to the internal consumer. But the US is choosing to lag behind. This will not look good in future history.
  28. Could global warming be caused by natural cycles?
    It must be confusing trying to use the UAH figures each month to try to determine the state-of-play of the planet. As well as desperately trying to convince yourself that because March 2011 has the same anomaly as March 1980, AGW has magically gone away, you would also be up and down, from happy to sad, like a jack-in-the-box : Most of 2010 highest since 1998 ? The globe obviously hasn't warmed since 1998. Jan 2008 lower than since the beginning of readings ? We are now in global cooling. Early 2007 showing highest anomalies since 1998 ? The globe obviously hasn't warmed since 1998. Jan 2000 lower than since the beginning of readings ? We are now in global cooling. 1998 the highest since the beginning of readings ? That's obviously not right and can be ignored, or used to state that the globe hasn't warmed since that time. Nov 1984 lowest anomaly ever (since the beginning of readings) ? We are now in global freezing.
  29. Dikran Marsupial at 20:24 PM on 3 May 2011
    Frauenfeld, Knappenberger, and Michaels 2011: Obsolescence by Design?
    chris@73 I suspect the reason paleoclimate people don't perform such a statistical analysis isn't because there is any methodological problem but simply that it doesn't tell you anything interesting whatever the result. It is not a valid argument to cliam that thr FKM test is invalid/inapropriate because paleoclimate people don't use that test - there has to be a first time for everything. So far you have given no statistical reason why the test is not valid (the data being too noisy is not a good statistical reason - it certainly doesn't make it "numerology"). The interpretation of the result of the test is another matter (c.f. my comment regarding frequentist statistical tests - being unable to reject the null hypothesis does not mean the null hypothesis is true, it never has and it never will). BTW, there was nothing "pseudo" about the statistical analysis of Douglass et al. They correctly applied the wrong test, but the test itself was perfectly correct statistics, it just didn't test what they thought they were testing.
  30. Frauenfeld, Knappenberger, and Michaels 2011: Obsolescence by Design?
    since we're being pedantic, I really should have said: "Santer's paper was addressing something quite specific - the question of the extent to which uncertainties in tropical tropospheric temperature could be used to invalidate expectations from models." And even that's not quite right, but I haven't got time right now to rewrite that sentence, and I expect you can see what I'm trying to say...
  31. Frauenfeld, Knappenberger, and Michaels 2011: Obsolescence by Design?
    O.K. fine Dikram. Yes the IPCC's designations ("likely", very likely") map onto estimates of probability ranges. However they don't address these with a numerical statistical analysis and assign measures of statistical significance to comparisons of contemporary and historical (paleo) parameters Santer's paper was addressing something quite specific - the question of the extent to which uncertainties in tropical tropospheric temperature could be used to validate expectations from models. Since a (pseudo) statistical analysis was used by ohers to attempt to infer that empirical measures and their uncertainties showed that empirical measures were inconsistent with models, it was appropriate for Santer et al to address the comparison with a statistical analysis. [apols for the long sentence!] However (and I may be wrong, since I haven't devoured every last bit of published data), I haven't seen any attempt by the paleo community to assign statistical significance to comparisons of contemporary and historical data (e.g. the paleo analyses of Mann, Briffa etc.). The reasons why this is a dubious approach is indicated in my post you just responded to. Of course one can do a statistical analysis of anything and assess apparent statistical significance in differences between whatever one choses. However attempts to do this in comparing paleodata with large uncertainties, to contemporary data with lesser uncertainty is playing at numerology. Of course if the authors of the paper were to test the statistical significance of differences between their model of paleo melt and their model of contemporary melt, that would be more acceptable even if the 95% confidence level significance is still somewhat meaningless in relation to what we'd really like to know (difference in real melt now and real melt then). But it's not up to me to address this in detail. That's the role of the reviewers of the paper...
  32. Could global warming be caused by natural cycles?
    Marcus at 18:39 PM, where are you getting the information that La-Nina is officially finished? The El-Nino Index is still in negative territory, about -1, and though it is weakening slightly, it is expected to strengthen again and remain negative well into 2012.
  33. Dikran Marsupial at 19:26 PM on 3 May 2011
    Frauenfeld, Knappenberger, and Michaels 2011: Obsolescence by Design?
    chris@69 There is no reason why tests of statistical significance cannot be used to compare observations with model hindcasts/reconstructions - it is done quite regularly by climatologists working with specialist statisticians (e.g. the Santer 17 paper). If you have a reason why this particular comparison is invalid, then you need to explain why in more detail. Secondly, the IPCC do not use qualitative estimates - if you look at box TS1 on pages 22 and 23 of the most recent WG1 report, you will find those "qualitative" terms map directly onto quantitative probability ranges. Without tests of statistical significance, how do you suggest scientists working with models avoid drawing conclusions from spurious correllations? Having said which, frequentist hypothesis testing is a bit of a mess anyway and many scientists and most of the general public tend to misinterpret the results of such tests.
  34. Could global warming be caused by natural cycles?
    "The problem fundamentally is the entire trend can be wiped out in just one year or so of natural variation." No, it can't. I think you're confused as to what a trend represents -- it's the average slope, not the temperature [anomaly] at a point in time. "In general, if the trend amount is less than the amount of observed variation over the trend, it's not outside the range of natural variability." If that were the criteria we would never be able to discern a trend in any observational series. I'd feel a whole lot better about my stock portfolio over the past 4 years...
  35. How climate change deniers led me to set up Skeptical Science website
    Marcus at 18:24 PM, you are confirming my point. Virtually everything I know about Monckton is through what I have read from the various threads devoted (did I say devoted?) to Monckton here at SkS. Unlike yourself I don't even feel the need to avail myself of even greater knowledge by scrutinising "The Australian" to see how much time they devote to him, or who invites him to speak. I only read "The Australian" online and honestly can't recall even seeing any mention of him there. Perhaps I need to seek out any mentions of him through their search function. Anyway, here seems to provide a more than adequate blow by blow coverage of his engagements. You now have me wondering who gives him the greatest attention, pro-rata that is, "The Australian" or SkS?
  36. Could global warming be caused by natural cycles?
    Indeed, RW1 is doing a *mega* cherry-pick. Pick a single month from the *least* reliable source (UAH) of *satellite* data (so failing to see the warmth in the polar regions), & even then he can *barely* achieve the result he's looking for. April here in Australia was pretty well above average-especially now that the La Nina is officially finished-so I wonder if he'll compare April & May results?
  37. Could global warming be caused by natural cycles?
    Wow, that's Cherry Picking at its *worst* scaddenp. I mean, hasn't he heard the saying "one swallow doesn't make a Spring"-the same can be applied to climate data. The simple fact that the monthly temperatures not only bounce back, but tend to bounce higher & higher every few years indicates that all that extra heat energy is still in the system, & continues to build up.
  38. How climate change deniers led me to set up Skeptical Science website
    Well John D, you might want to ask that bastion of "Skepticism"-The Australian-why they frequently devote so much space to the rantings of Monckton & Plimer? Also, why is Monckton frequently invited to give testimony at Congressional Hearings in the US, & why do the various skeptic conventions around the world frequently feature one of these two people as Guest Speaker? You might not credit them with too much importance or influence, but I'm afraid you're still in a minority amongst your fellow "skeptics".
  39. How climate change deniers led me to set up Skeptical Science website
    It has always fascinated me the amount of attention, threads and posts that are directed against Plimer and Monckton by the more regular contributors here. They are obviously seen by many here as being far more important and influential than what I or most sceptics seem to credit them with.
  40. Ken Lambert at 17:52 PM on 3 May 2011
    How climate change deniers led me to set up Skeptical Science website
    chriscanaris #53 "I don't recall any sceptic here citing Plimer or Monckton in support of their positions both of whom I find somewhat an embarrassment (but I'm happy to stand corrected)." Well I have never quoted the work of Plimer or Monckton in any of my arguments put forward on SKS. chriscanaris: "the sheer weight of ad hominem argument levelled at Ken beggars belief and can't go unremarked." The reason for that attack was the attackers were shown by my reasoned argument and calculations to be factually wrong on several important numbers. This unleashed the torrent of abuse.
    Response:

    [DB] Your failed attempts to recast the dialogue of the Flanner thread to cover your errors are transparent.  Multiple transgressions of the Comment Policy have forced moderation; your subsequent blaming of the moderation as cause for your failure to prove your arguments ring hollow, as does your trying to reframe comments critical of your retreat & diversion escape plan as being "abuse".

    You were in error, you were corrected on the error, and you have spent weeks trying basically saying "no I wasn't".  Black Knight Syndrome embodied.

  41. Frauenfeld, Knappenberger, and Michaels 2011: Obsolescence by Design?
    Chip Knappenberger 1 - Why are comments not allowed in response to your post on this paper at worldclimatereport.com? 2 - How is interesting historical data from a few sites relevant to the multiple integrated observations of warming and melting over most of Greenland, the Canadian Archipelago and indeed the entire Arctic? I ask question 2 in the context of Patrick J. Michaels' post at the Cato Institute in which he uses this already obsolete paper in conjunction with another debunked paper to conclude that: "...the recent increase in melt across Greenland (contributing to a negative trend in SMB) may in part a result of rising temperatures from sources other than dreaded greenhouse warming, and therefore extrapolating the observed trends in SMB forward may not be such a great idea." http://www.cato.org/... It is interesting that Michaels seems focused on the idea that beachfront property is - presumably - a good investment because coasts are not at risk. Would you do him the kindness of directing him to recent studies which show that he should rapidly dump any such investments which he may have in more northern latitudes? http://www.sciencenews.org/view/generic/id/73737/title/With_warming,_Arctic_is_losing_ground It is ironic that Michaels posts under the banner 'current wisdom'. Wouldn't the banner 'obsolete folly' be more apt?
  42. Waste heat vs greenhouse warming
    KR 419 When the sun shines, it is because there is an open sky. The ground warms, and this heat sees the same open sky. Cooling by radiation is optimal. When the sun doesnt shine due to cloud cover, while conditions for radiative cooling are less optimal, there is also less heat to radiate in the first place (due to the clouds). Along comes humanity doing something else. Adding heat incessantly, regardless of cloud cover night or whatever. Then come the denialists saying this isnt a problem, and that things are warming mainly due to the extra CO2. Extra heat being trapped when radiative cooling conditions are optimal (i.e. see first paragraph above).
  43. Could global warming be caused by natural cycles?
    He is just looking at March and comparing to every other month, not the annual global average. Its not even especially low.
  44. How climate change deniers led me to set up Skeptical Science website
    The Albatross has landed. Best wishes to all.
  45. Waste heat vs greenhouse warming
    muoncounter 420 "The waste heat is irrelevant." If the waste heat coming out of a power plant was on whole being lost in the form of thermal radiation, no one would be able to approach it. Instead of requiring an ultra sensitive CCD to amplify this energy for your photos, you could just raise your hand and feel it. The plant is cooled by the mass of fluids (air and water) carrying 99.999% of the heat away, and it appears you are underestimating the mass associated with these fluids.
  46. Could global warming be caused by natural cycles?
    RW1, do you even bother to check your claims? The average global temperature anomaly for 1980 was +0.02 degrees C above the 1979-2000 average. In 2008, the temperature was +0.1 degrees above the 1979-2000 average. Given that 2008 was (a) a La Nina year & (b) the nadir of the previous solar cycle & (c) Given that there are some pretty significant holes in the coverage of the satellite temperature measurements, I think this kind of debunks your entire premise. Of course, looking at year-to-year variability is a complete strawman anyway, what is more important are the following facts: (1) The average temperature anomaly for each decade has been *warmer* than the decade before. (2) The difference between the temperature anomaly for each decade is getting *larger*. (3) That the trend-line for warming is statistically significant. Now, if this were all down to just internal variability, then at least one, if not all, of those facts above shouldn't be the case. The question then remains. How, in the absence of a downward trend in Total Solar Irradiance, do you explain a total of +0.5 degrees of warming between 1979 & 2009?
  47. Frauenfeld, Knappenberger, and Michaels 2011: Obsolescence by Design?
    skywatcher at 10:45 AM on 3 May, 2011 No I don't think it's reasonable at all. One cannot make interpretations about statistical significance when comparing empirical contemporary data determined using one method, with historical data constructed with a model. This is partly the reason that the IPCC use qualitative estimates in these sorts of comparisons ("likely"; "very likely" etc),and why papers on paleotemperature reconstructions don't include measures of statistical significance. It's easy to see some of the problems. For example historical date reconstructed with a model have large associated uncertainties. All it requires for contemporary data to be "not statistically significant" with respect to the historical reconstruction, is that one has large error bounds on the historical data. It then becomes very difficult for differences in the contemporary data to achieve statistical significance, especially at the 95% confidence level. So I think the inclusion of statistical significance was entirely unwarranted, and the truly offending statement shuld have been removed from the abstract. Unfortunately, at least one reviewer of the paper gave the authors a free pass on this. He's shown us his confidential review which remarkably classed the methodology as "good" and raised not a peep about the statistical analysis. It's very unfortunate....
  48. trunkmonkey at 16:04 PM on 3 May 2011
    Models are unreliable
    360. The signature of the burning must be included in the ice cores, so I concede this, except for the possibility that the models are initialized a bit too high. Mizmi is the real expert but grasses are C4 plants adapted to the declining CO2 levels of the Pleiocene. They use less CO2 that the forest they replace.
  49. Frauenfeld, Knappenberger, and Michaels 2011: Obsolescence by Design?
    Tom Curtis at 12:18 PM on 3 May, 2011 Tom, I can only say again that I agree with you. As you pointed out above, and I pointed out here (see point [4]), there are some categorically incorrect statements in the paper that simply shouldn't have been allowed to stand. Unfortunately the main reviewer of the paper chose not to address these. So we can only complain about the situation after the fact. In my opinion Dr. Box could hardly have done a better job of playing into the hands of the misrepresenters. It's unfortunate to have to say so. Dr. Box had an opportunity to re-review the paper in early Jan 2011. Apparently the temperature/melt data used to compile the MKF reconstruction wasn't available to update their model to include 2010, and the editor chose to over-rule the recommendation that the authors delay publication to wait for this (an acceptable editorial decision in my opinion). However the melt data described elsewhere was available at least by late December. Therefore Box was in a very strong position in early Jan 2011 to give very strong guidance to the editor that categorically false statements MUST be removed from the paper in the light of independent data that shows the 2010 melt to be a new record. If this was done MFK would have been in a much weaker position in their attempts to misrepresent the relationship between contemporary and historical melt.
  50. trunkmonkey at 15:51 PM on 3 May 2011
    Models are unreliable
    scaddenp 359: "That would be why DO have climate effects coming out of interglacial but not now?" Does the system really care about glacial/interglacial stage? Isn't meltwater, meltwater, whenever it ocurrs? If our efforts have accelerated the melting, does it matter that the triple net Milankovitch "forcings" languish in the future? Berenyi Peter, 355., is saying that he sees no SST increase. (Alley 2005) has an interesting discussion of this. He states that several models predict meltwater, but that the results are equivocal.

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