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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 62701 to 62750:

  1. The Independence of Global Warming on Residence Time of CO2
    "t is reasonable to suppose that this was the release of methane from clathrates trapped" However, isotopic evidence from CH4 in ice bubbles points to this being of swamp or oceanic source rather than clathrate.
  2. The Independence of Global Warming on Residence Time of CO2
    You would have to be incredibly blinkered to maintain that the carbon increase in the atmosphere is not anthropogenic. However, not to forget that atmospheric carbon increased sharply at the end of each glacial and was virtually certainly the result of the melting and not the cause. It is reasonable to suppose that this was the release of methane from clathrates trapped under the 3km of ice with the methane sourced from shale, coal and oil deposits over the 100k years the ice existed as well as from the anaerobic breakdown of organic material. On release it would have been rapidly oxidized to Carbon dioxide. If Greenland melts, there may be similar deposits waiting under the ice to further push global warming. http://mtkass.blogspot.co.nz/2011/08/end-of-ice-ages.html
  3. The Certainty Monster vs. The Uncertainty Ewok
    "As I understand it, there are really only three options that can explain Curry's nonsensical hypotheses: 1) She has not read the ARs. 2) She has read the ARs, yet chooses to misrepresent and distort their content and even fabricate strawmen, 3) She is not well and is losing control of her faculties." When Curry first went public with her odd ideas, she engaged Gavin Schmidt in a lengthy thread over at RC. It was clear that either she hadn't read AR4, or she had only skimmed it superficially. She made many of the arguments then that she continues to make now, and Gavin and others did their best to educate her on what the scientific work that underlies the IPCC reports (and the reports themselves) say. She's been corrected a multitude of times since, including the responses to her "uncertainty monster" paper. Yet she's not budged an inch. It's possible that #2 is true but I wouldn't be surprised to learn that #1 (is still?) true. I don't think #3 is true. It's really frustrating to see someone in her position remain absolutely deaf to all attempts to educate her as to her mistaken assumptions about mainstream climate science. It's one thing when someone who's relatively uneducated like anthony watts refuses to learn. But a department chair at GIT? geez.
  4. Scafetta's Widget Problems
    Hmm, when someone postulates that their forecasting tools are going to better than physical models, then I sense the possibility for a bet. So when do you think your "model" will deliver a climate that is outside the predictions of climate models?
  5. Fritz Vahrenholt - Duped on Climate Change
    Elsa you are repeating "But the problem for your side in this is that it results in a theory that cannot be falsified." Repeating this does not make it true. Climate theory makes predictions all the time. For a given set of forcing, you will get a given climate. (ie a 30 year average). Even the primitive model that was basis for Broekner paper got climate for 2010 right within the constraints. Your comment on this was to complain that the paper didnt predict decade of only slowly rising temperatures. Well of course it didnt because even the most advanced climate model today has no skill at decadal predictions. I would note a recent comment from Gavin Schmidt. "Obviously people have thought of this and there are a number of ideas that are being tested - but none of them really give what it wanted (i.e. predictions that will reproduce the interannual ups-and-downs that you could compare directly to the obs). For instance, a lot of work is being done on initialised predictions where you take the ocean state for the last few years, attempt to synchronise the various 'oscillations' and then run it forward. This shows some skill for a few years in something like the AMO, but can't give realistic ENSO forecasts longer than the specialised ENSO forecasting systems (i.e. 6 months or so). So the interannual short-term variability doesn't seem to be predictable. There are also big issues with drift in these runs, which makes even the multi-year trends someowhat difficult to interpret. Another idea is run multiple ensembles for short periods, pick the one that is closest to reality and continue the next set of ensembles from that one and so on. But this only produces a plausible hindcast that is attuned to the actual interannual variations, not a prediction. The fundamental issue is that it is likely to be very hard (if not impossible) to predict ENSO phase 5 or 10 years ahead of time and that puts a real limit on how good any short term predictions can be.- gavin" You seem to be claiming that because you cant falsify a model with tomorrow's temperature, then its not falsifiable. This is wrong. Look at how well climate models predicted climate instead. Your "repeat but with one variable changed" approach does not work in many of the natural sciences. Fortunately we have developed the tools (contrary to your earlier false assertion) for dealing with multivariate hypotheses. It is possible to imagine all sorts of futures which would invalidate models.
  6. The Certainty Monster vs. The Uncertainty Ewok
    At least the title of this article makes sence. From my experience, the idea that there is actually a serious debate over climate change is what causes most inaction, not the actual arguments of the deniers.
  7. The Certainty Monster vs. The Uncertainty Ewok
    DSL, Curry still teaches and has grad students. My advice to any grad students considering enroling in the School of Earth and Atmospheric Sciences at GIT would be to run away and fast.
  8. Michael Hauber at 11:35 AM on 2 March 2012
    The Independence of Global Warming on Residence Time of CO2
    'Michael Hauber In the scenario you suggest, where the hypothetical sink were controlling atmospheric CO2 levels, the level would remain near the equilibrium level, rather than rising rather rapidly.' Not if the equilibrium level is determined by temperature, and temperature is rising rapidly. As an example, consider a see-saw with a small bucket on one side (atmosphere) and large swimming pool on the other side (ocean). Connect them with a pipe, and poor water slowly into the bucket, while tilting the see-saw so that the bucket gets lower and the swimming pool gets higher. With the right balance, it would be possible to pour water into the bucket at a rate faster than the water level in the bucket is rising. Water would be flowing through the pipe from the bucket to the swimming pool. But the level in the bucket would not be determined by the amount of water poured in, but by the tilt of the see-saw. I certainly do not believe that the oceans are responsible for the increase in Co2, but pointing out it is theoretically possible, unless you consider additional facts beyond what is presented in your argument.
  9. Scafetta's Widget Problems
    "... which is not the gravitation of Sir Newton, but the density of the volumes." I recall from the Cosmos TV series when Carl Sagan noted that the gravitational attraction of the obstetrician was larger than that of Jupiter, Saturn, or Mars - simply because (s)he was much closer. Thus throwing some severe doubt on astrology... Volker - Quite seriously, if you cannot point to a physical mechanism (a testable one, with some evidence), you are simply engaging in climastrology.
  10. Scafetta's Widget Problems
    "... which is not the gravitation of Sir Newton, but the density of the volumes."
    Oh my! And next up from Volker, how white dwarf and neutron stars hundreds of light years away, with extreme densities (but somehow nothing to do with their gravity), control the future of the Solar System ... Sphaerica's point #57 resoundingly seconded!
  11. Bob Lacatena at 10:43 AM on 2 March 2012
    Scafetta's Widget Problems
    Volker,
    I do not need a mechanism...
    To be taken seriously, yes, you do.
  12. Volker Doormann at 10:25 AM on 2 March 2012
    Scafetta's Widget Problems
    Dikran Marsupial wtote at 07:12 AM on 2 March, 2012: “Volker, the scientific component of my objection was that you had not demonstrated that the coherence was anything more than temporary and actually existed throughout the satellite records.” I have demonstrated, and AFAIK as the _first_ researcher in climate, that there is coherence between the main frequency of the season cleaned sea level oscillations of the satellite records with the frequency of the heliocentric synodic tide function of the couple of Mercury/Earth over the whole time interval of the satellite measurements as a fact. I have no idea what mechanism is involved in that coherence; the fact is that the phase coherence shows high sea levels if the solar tide function shows spring tides and vice versa. And the high sea level peaks are also visible in global temperatures of the UAH satellite measurements as a higher temperature. If you call this a not more demonstration, that is your freedom; but I think it is worth to discuss it in the science community because a possible mechanism can bring more light into the basic question of the cause of the global warming. “I also pointed out that you had not performed a statstical analysis to see if a temporary coherence is surprising. Those are both valid scientific points, which you have refused to address.” I have refused your claim because I not agree with you on that analysis. A trained eye is able to see in a graph if there is a correlation or not. I have no possibility and no software to calculate a correlation coefficient. But each interested guy can perform such coefficient, because all date are public. It is not necessary that I must perform that. An other point is that the statistic tool is not an adequate tool to get a significance here; a significance is given better by a great number of comparisons of well known temperature reconstructions or proxies with the all the relevant solar tide functions, like A. Moberg et al, Bond et al, Zorita, R. Edwards, Mangini, G. Patzelt, and 10+ more, inclusive hadcrut3 and UAH. But as you know, there are differences between the proxies, maybe from different chemical processes in stalagmites and tree rings. I have done some hundred comparisons and have found by empery the strength of the tide functions of the several couples. “There is also the point that, like Scafetta, you need a plausible physical mechanism that can explain the strength of the effect, not just the correlation/coherence.” No, you are wrong. To realize a precise climate forecasting tool for the next millennium I do not need a mechanism, I do need only the NASA ephemerides and the empirical fitted tide function strengths. But nevertheless I have some hints about the physical background, which is not the gravitation of Sir Newton, but the density of the volumes. Rest snipped. V.
    Response:

    [DB] ...

    DNFTT, people.

  13. Dikran Marsupial at 09:44 AM on 2 March 2012
    Fritz Vahrenholt - Duped on Climate Change
    Elsa, Do you actually know which observations Plass used? Have you read the paper? Elsa wrote "But the problem for your side in this is that it results in a theory that cannot be falsified." This is not true, as I have already pointed out here where I wrote "If we have data or projections for the other forcings, then we can use the theory to determine/project the plausible range of the response to the combined forcings. If the observations lie outside that range then the theory is falsified. It really isn't rocket science." How do we disentangle the various effects of different forcings? Using something called an attribution study. There is a wide body of literature on this subject, start with the relevant chapter of the IPCC WG1 report. Thus it seems to me that not only are you unwilling to answer questions, you are also ignoring the responses to your assertions. As DB suggests, DNFTT seems the appropriate response. You had your chance to demonstrate that you were interested in the science by looking at the work of Plass; sadly it is clear that you are not interested in the answers to your questions.
  14. Scafetta's Widget Problems
    Note, the figure shown by skywatcher @54 is essentially the same as Figure 6 in the post above (with a few minor differences).
  15. Scafetta's Widget Problems
    I was constructing a response to a comment which made unsupported assertions, which has gone as I previewed, but for the benefit of readers, here's RealClimate's take on comparisons between AR4 models and data. Give me these over climastrological cycles any day! RealClimate 2011 update to model-data comparisons
  16. Fritz Vahrenholt - Duped on Climate Change
    pbjamm (-Snip-)
    Response:

    [DB] The topic of this thread is Fritz Vahrenholt - Duped on Climate Change; please stay on-topic.

    Off-topic portion snipped.

  17. Daniel Bailey at 09:09 AM on 2 March 2012
    Fritz Vahrenholt - Duped on Climate Change
    And with this most recent comment, elsa stands revealed as full-blown troll. DNFTT.
  18. Fritz Vahrenholt - Duped on Climate Change
    elsa@86 "But the problem for your side in this is that it results in a theory that cannot be falsified. Whatever happens the theory can be made to fit the facts." I would certainly hope that the theory fits the facts otherwise it is worthless. If we followed your model of science then it would be impossible to expand knowledge when new information was learned. All old ideas and theories would have to be completely discarded when anything new was learned that was not explained entirely by the old. Rubbish
  19. Ocean acidification isn't serious
    As Science is behind a paywall, here's a link to a report on the recently published Hönisch et al. (2012). The study found that, if CO2 emissions continue at their current rate, we're on track for ocean acidification unprecedented in the last 300 million years. Muttkat, perhaps you can show us why the testimony has value. Where is the science? And have you read the series on ocean acidification from working scientists Doug Mackie, Christina McGraw, and Keith Hunter?
  20. Scafetta's Widget Problems
    It's a good thing if people can come here and engage. There is a wide gap in understanding among most of the people out there. To close off this forum to most non-scientists and to people who don't already understand and obviously can't agree would represent a missed opportunity.
  21. Fritz Vahrenholt - Duped on Climate Change
    Dikran You asked me "Please tell me which observations he used that are non-repeatable." I repeat the answer is all of them because the world does not stand still. We cannot try to test eg the temperature with a given level of CO2 and all other factors being equal over and over again. Each of them will have moved on and be different so the circumstances that we need to test the theory in a meaningful way cannot exist. You then say "CO2 radiative forcing is only one of the forcings that govern long term climate, as it says, for instance in the IPCC WG1 report. Does AGW theory say that temperatures cannot fall while CO2 levels rise? No, it doesn't." I completely accept that. But the problem for your side in this is that it results in a theory that cannot be falsified. Whatever happens the theory can be made to fit the facts. That is not to say that your theory is wrong (although I think that quite likely) but it not a scientific one for the simple reason that we cannot test it in any meaningful way. How can we disentangle the various effects of CO2, other greenhouse gases, water vapour,aerosols, sunspots just to name some that we know of? How about the ones that we do not know of?
  22. Scafetta's Widget Problems
    DM, since this is authentic climastrology, perhaps we can persuade Tamino to waste his time by performing said statistical analysis for Volker. I'm sure Volker would welcome the chance to have an independent statistical analysis of his theory. I'm certain that if Tamino found robust significance across a variety of tests, he would help publish the findings. I do wonder, though, if Volker would abandon the theory if no significance was found.
  23. The Certainty Monster vs. The Uncertainty Ewok
    I disagree, Dana. The cartoon does makes sense. The problem is that the sense is completely uninformed by a well-understood convention that Curry, once upon a time, completely agree with. How much more evidence is necessary before the conclusion that she is incompetent can be generally drawn? Does she still teach? Or has she become an administrator?
  24. Scafetta's Widget Problems
    >> [JH]You have astutely avoided telling us what you are attempting to acheive in your serial and rambling postings. I came here to learn and to discuss. Learning is an engaging process. I believe I speak for most humans when I say that learning is weak if done by rote. You have to lay your doubts out on the table. My communication skills are rather limited, so perhaps I ramble more than makes you comfortable. I thought I was following the Comments Policy that I have seen pointed out to others.
    Moderator Response: [JH] I just wanted to make sure that you were not here to make mischief. My aplogioes for being gruff. Please proceed.
  25. The Certainty Monster vs. The Uncertainty Ewok
    Josh has a problem with the concept of 'statistical significance', I see.
  26. Radiative Balance, Feedback, and Runaway Warming
    Ricardo, currently a moderator (JH) believes I am "meandering". I asked for clearer guidelines on what to comment and what not to comment, eg, so I can avoid this "meandering". http://www.skepticalscience.com/news.php?n=1293#76064 I did not major in communications, that's for sure. And it does bother me not to come through clearly. To keep this fairly short, thanks for your information (the optical thickness part). I still think there is an apparent coincidence not yet covered on the temperature-pressure near matchup. [I would have to calculate optical thickness height to the lower .7 albedo flux at TOA and verify that this Venus lapse rate line sort of overlaps the similar slope line on earth by the time the pressures line up.] And the "non-GHE" case was not of 100% N2 with absolutely no ghg (I should have been clearer) but of using very low ghg % such as we find on earth. The 0 GHE case is trivial, as you pointed out. Sorry for the confusion.
  27. The Certainty Monster vs. The Uncertainty Ewok
    Lars - yes, I saw that. The cartoon makes no sense whatsoever, and then for Curry to say it "encapsulates all this" just made me shake my head in disbelief. It's bad enough for a climate scientist to advertise a cartoonist who constantly belittles climate scientists (I rarely visit Curry's, but have seen her post several Josh cartoons), but then to claim that particular cartoon makes sense is just astounding to me.
  28. Scafetta's Widget Problems
    JH#47, "meandering comments"? It would really help me know what you were talking about if you were a little more specific. I would like to know what questions or replies can be entertained here and which can't (maybe using a few samples of what I wrote). I can try to keep the forbidden comments to some other website and here stick to what is allowed. The closest possible violation I saw from the Comments Policy would be being off-topic. Although I was specifically invited to come and reply on this thread.
    Moderator Response: [JH]You have astutely avoided telling us what you are attempting to acheive in your serial and rambling postings.
  29. Lars Karlsson at 07:19 AM on 2 March 2012
    The Certainty Monster vs. The Uncertainty Ewok
    Have you looked at the Josh cartoon that Curry links to? "Josh encapsulates all this with a cartoon." I mean, seriously...
  30. Dikran Marsupial at 07:12 AM on 2 March 2012
    Scafetta's Widget Problems
    Volker, the scientific component of my objection was that you had not demonstrated that the coherence was anything more than temporary and actually existed throughout the satellite records. I also pointed out that you had not performed a statstical analysis to see if a temporary coherence is surprising. Those are both valid scientific points, which you have refused to address. The component of my post that was speculation was clearly labelled as such, and so is no excuse to dismiss the substantive scientific issue. There is also the point that, like Scafetta, you need a plausible physical mechanism that can explain the strength of the effect, not just the correlation/coherence. If you are interested in scientific based dialogue, then you need to conform to the conventions of science, for instance performing a proper statistical analysis of the data, or responding constructively to criticism, by for example, demonstrating that the claimed coherence is not merely a temporary artefact.
  31. Volker Doormann at 06:54 AM on 2 March 2012
    Scafetta's Widget Problems
    [DB] wrote: “If you did not wish to participate in science-based dialogue, of which experimental repeatability is an integral part, than why are you here?” (-snip'Complex question / Fallacy of interrogation / Fallacy of presupposition. The question presupposes a definite answer to another question which has not even been asked.'-) Dikran Marsupial wrote at 06:53 AM on 1 March, 2012: “If the coherence exists over the extend of the satelite record, then plot a graph of the coherence across the satelite record, better still, perform a proper statistical analysis. I suspect the coherence doesn't extend over the whole period of the observations, which would imply that the correllation is no more than a temporary correllation and is essentially meaningless.” I have given my arguments regarding that my astronomical method to forecast the climate is based on the real geometry and real objects in the solar system, while the math of N. Scafetta is not. If Dikran Marsupial has an idea or a theory or a personal suspection it is his personal opinion. A science based dialogue would take my given arguments and either one agree with or refute the method in a scientific manner. You are wrong, if you presuppose that the reply of D.M. is science based; it is not. On 1 March, 2012 at 06:42 AM I have given 8 URL’s of graphs, showing the results of my method including several thousand repetitions of solar tide periods. If you wrote your response some two hours later on 09:18 AM on 1 March, 2012, you must have had knowledge on the repeatability. Last point. If you are interested in a scientific based dialogue, the suspect to a person is not a method of science. V.
    Moderator Response:

    [DB] Buck up, answer questions put to you directly and spell out the physical causal mechanisms that support your hypothesis (_not_ a theory) complete with what significance testing you have done. 

    Failure to do so is an abject admission that you are practicing climastrology, not science.

    Pointlessly off-topic snipped.

  32. Scafetta's Widget Problems
    KR >> it is extremely difficult to tell whether they are different fits or not. I think I see your point. I would assume that the fits followed some standard algorithm or goal (eg, maximize xyz). If key algorithm/function details for setting up the equation for each half actually come from an analysis of the whole (consciously or subconsciously), then that would spoil the predictive claims. >> hand-tuning ... There's a significant risk of confirmation bias. Yes. >> ..a small set of cycles ... There's a significant risk of confirmation bias. Well, the small number of cycles mostly appear to come from a standard approach I think. You did mention the 4yr cycle but that might just be a detail. >> not terribly useful for predictions when the underlying forcings are changing. Although frequency analysis can help identify patterns that were not seen before. It can augment MLR used by L&R08. It may give insight into PDO, AMO, and other such cycles. It may identify subtle coupling or small cycles within the cycles. I may help clean out their precise boundaries. It may also help understand shorter term ENSO. The derived data is data with a fresh face and that can help future efforts to understand the physics. I have not read Lean and Rind 2008 (nor the details of Scafetta'11), but I have heard that the models are not generally designed to deal with very short-term "weather". If a sound approach using frequency analysis proves to track future changes fairly closely for 1-30 years after the training period (ie, the range where many models are weak ??), then it seems modellers would want to improve the models in this way. It may be cosmetic to "tune" the model officially once per decade, but all else being equal who wouldn't prefer to have their model reduce short-term error significantly?
    Moderator Response: [JH] Your serial posting of meandering comments suggests that your primary objective may be to "gum-up" the SkS comment threads. Deniers who have previously played this game have been banned. We are closely monitoring your activity.
  33. Greenhouse Effect Basics: Warm Earth, Cold Atmosphere
    Professor Ray Pierrehumber had an excellent review paper on this topic Infrared Radiation and Planetary Temperature
  34. Radiative Balance, Feedback, and Runaway Warming
    GC - why would you give time to such astrology when there is perfectly good physical explanation for climate? Scafetta has another problem - how to explain why the known physical properties of GHGs do NOT affect climate, given the observed effects on DLR.
  35. Radiative Balance, Feedback, and Runaway Warming
    Jose_X we already talked about the no-GHE case and you replied that it was not your interest ("My second scenario is not 100% N2 (which is this simple case you answered)"). Keeping in mind that we're talking about a rather crude aproximation, if you have a not too low absorbtion the lapse rate is not determined by the exact amount of greenhouse gas absorption, it's determined by specific heat and gravity. Where absorption matters is in the optical thickness as function of height needed to determine where to start extrapolating backward to the surface. You may easily understand that it's not by chance or other weird reasons that the temperatures in Venus and Earth atmospheres are similar for equivalent pressure levels. It's not that "it seems to cast some doubt to what all of that CO2 is doing."
  36. The Certainty Monster vs. The Uncertainty Ewok
    OT I was always a bit disappointed that the Ewoks were not actually Wookies (or a similar race); it would have been so much more believable that Wookies could tear up stormtroopers. Fighting a Wookie in close quarters would have been, ah, frightening. Yeah, Lucas wanted primitives to defeat the techie STs, and Wookies have tech, but hey, still today, some humans are still in the stone age. It isn't as though technology spreads everywhere instantaneously; though, it sure seems that way.
  37. Radiative Balance, Feedback, and Runaway Warming
    Ricardo 67>> In the real case, use the adiabatic lapse rate, the emission altitude from the effective radiation temperature and extrapolate back to the surface. I do thank you for the advice even though in this case I already knew what you stated, but the problem is that if we are going to test GHE vs no such effect I don't think measuring the lapse rate is acceptable since we only have one Venus like planet to measure (so we can't measure the w/GHE and also the w/o GHE cases). The idea would be to derive the lapse rate for the GHE and for the non-GHE cases and compare those two to each other (and while we are at it, compare the GHE case to Venus measurements).
  38. Radiative Balance, Feedback, and Runaway Warming
    I noticed a piece at the beginning of #66 was snipped. "Ricardo, (-snip-)". It's probably a good thing that was snipped although no insult was intended. Here is a translation of what I had written. "Ricardo, I was going to state at the top of that comment that Huffman appears to have a lot of anger towards the climate science community." The intention of that line above would have been to warn anyone who went to read that link not to get distracted with the snide remarks (and outright insults) against climate science that pepper the website; however, I did opt not to forewarn anyone when I provided the link, and then Ricardo apparently found the link offensive and made it clear he did not like/trust the person. Of course, I was not asking anyone to like or trust the person. As I already explained, I had offered the link for reference purposes to the question I had about the GHE on Venus.
  39. CoalGeologist at 05:22 AM on 2 March 2012
    Greenhouse Effect Basics: Warm Earth, Cold Atmosphere
    Thanks to all for the subsequent discussion. I'm glad I asked! I see nothing wrong with owl905's "pool table" analogy ( @34), as further explained by CBDunkerson ( @40). Tom Curtis's "pipe" analogy ( @36) can be reconciled with the pool table simply by coiling the pipe so that the outlets occur at the same point. If the pipes are carrying heat (and there's no internal friction), then the flow rate will be the same, yet the spatial concentration of heat will be greater in the longer coiled pipe (a hookah?) than in the shorter straight pipe (a calumet?). (With apologies to Ray Pierrehumbert and others, I like a nice, simple model much more than differential equations, though I'm glad someone can figure out the associated math!)
  40. Scafetta's Widget Problems
    Jose_X - Since Scafetta's two fits (1850-1950 and 1950-2010) are both hand-tuned, using the same basic cycles and almost the same phase shift as each other, and since they are derived from his earlier work with much the same 60-year cycle, it is extremely difficult to tell whether they are different fits or not. Note that hand-tuning a small set of cycles (which are representative of, but not the primary components of, the signal - Tamino found a roughly 70-year cycle to be the peak for this data set) is not the equivalent of analyzing the data and seeing where it leads you. There's a significant risk of confirmation bias. I'm not ignoring the partial data sets he used - but I will point out that hand-tuning can lead you to assuming your consequent. Other notes: The Loehle and Scafetta 2011 paper referenced in the OP states that these cycles are strictly short term variations, that: "The residuals showed an approximate linear upward trend of about 0.66°C/century from 1942 to 2010. Herein we assume that this residual upward warming has been mostly induced by anthropogenic emissions, urbanization and land use change. The warming observed before 1942 is relatively small and is assumed to have been mostly naturally induced. The resulting full natural plus anthropogenic model fits the entire 160 year record very well. " (emphasis added) And given that Lean and Rind 2008 clearly show that short term variation is actually attributable to solar, volcanic, ENSO, and anthropogenic influences, not astronomical cycles, Scafetta's work really does not hold up. --- 'Curve-fitting' is analysis, a description. Not a model, not the underlying physics, and not terribly useful for predictions when the underlying forcings are changing.
  41. Scafetta's Widget Problems
    Jose_X - solar activity is very difficult to predict. Solar cycles 24 and 25 are both expected to be weak ones, however.
  42. The Certainty Monster vs. The Uncertainty Ewok
    Yes, the Ewok managed a very creditable showing against the Evil Empire, at the end of the day--er, movie. The storm troopers were certainly frightened of them by then! I had wondered if perhaps Dr. Curry's 'not cherry picking' comment was trying to invoke the notion of falsification via one negative result--a la Einstein's "I can never be proven right. . ." But it's hard to quite make that thought work--finding a stretch with less warming surely doesn't allow one to beg off proper assessments of significance.
  43. Scafetta's Widget Problems
    dana1981 (or anyone), what does climate science say about the ability to "predict" solar intensity? I really have very little idea of how much this intensity is anticipated, except that there is some sort of 11-year cycle. Do we have bounds for the range? Also, does anyone have a link to a sensitivity study? Thanks. [.. now back to google]
  44. Scafetta's Widget Problems
    gallopingcamel @38 - the models used in the IPCC report are physically-based and physically-constrained. Scafetta's is not. That is why the latter is curve fitting (allowing variables to fit the data unconstrained by physical reality) and the former is not. To be blunt, Alec Rawls has no idea what he's talking about. He is clearly entirely unfamiliar with the body of climate science (and solar) literature. His comments are based on his 'gut feeling' whereas the IPCC is based on a comprehensive literature review. Not unlike the difference between the IPCC and Scafetta.
  45. Volker Doormann at 04:10 AM on 2 March 2012
    Scafetta's Widget Problems
    gallopingcamel at 01:53 AM on 2 March, 2012 says: “Scafetta has found a strong correlation between planetary motions and short term climate changes. “ No. Scafetta has several time cycles in years of sinusoid function superimposed and fitted in time and amplitude to a short time interval of the global temperature spectrum. This has nothing to do with neither astronomy nor planetary motion. It’s simple Math. “For his theory to gain traction he must develop a plausible mechanism to support his theory.” (-snipI think here is a general misunderstanding about the basic elements in science. A mechanism is an element of the science of physics, because physics deals with forces and causality. Causality is the idea that a cause is followed in time by an effect. There are other elements in science than physics: logic and/or geometry, which have no mechanism. There are also motions of two objects and it is impossible to say, which object follows ( http://de.wikipedia.org/w/index.php?title=Datei:Orbit5.gif&filetimestamp=20050818225817 ) It is a perpetual mobile because it moves without any drive energy or loss energy over millions of years. There is no time delay in this motion, only a ratio of 3:2 in the geometry.-) (-snipThis may show, that geometry is first relevant, also in astronomy and gravitation, but not a mechanism. The logic goes that if there is a geometric connection from the science of geometry in nature than physics can look for a possible mechanism if there is any. -) V.
    Response:

    [DB] Off-topic meanderings snipped.

  46. Scafetta's Widget Problems
    KR, but if you guess blue, you will be right a fair amount of the time. If you identify that blue is correct 35% of the time, you may be able to improve your existing physics model which had been accounting for blue 40% of the time. Frequency decomposition is not the end of it because there truly are many cycles in nature (expect blue a very large portion of the time every 24hrs starting at noon). Further, I mentioned that a claim was made in the paper that weighing to 1850-1950(?) was able to do a very good job predicting (the untrended cycles) from 1950-2000. Also, teaching/testing with the periods flipped also did very well. You are ignoring that. The odds of that happening (for red noise) are very small. [I'm assuming there was actually a "good" job done.. say relative to what a typical climate model would do.]
  47. The Certainty Monster vs. The Uncertainty Ewok
    Now, "the uncertainty Gungan", that I can get behind without reservation. :)
  48. The Certainty Monster vs. The Uncertainty Ewok
    Incidentally, as a fan of the old Star Wars trilogy I must raise some slight protest regarding (a) the use of a photo of what is unambiguously the Ewok character named Wicket to represent 'Philip the uncertainy Ewok', and (b) the suggestion of Ewoks that "they are nothing to be scared of" given the role played by the Ewoks in the film Return of the Jedi. Tongue firmly held in cheek, of course.
  49. Radiative Balance, Feedback, and Runaway Warming
    Jose_X - I have replied here.
  50. Scafetta's Widget Problems
    Jose_X - "The model states essentially 1850 < t < 2000 and 2000 < t < 2100 iirc. To hindcast further is interesting but void." In that case Scafetta's model is nothing more than a limited description of that data. Such a description provides no ability to extrapolate outside the period, either in hindcast or forecast (to quote, "interesting but void"). It's not a model, it's a frequency decomposition. I can look up at noon and provide a description of the sky - "It's blue!". But this says nothing about the physics of the interaction of light and air, and will not allow me to predict a red sky at dusk/dawn. Scafetta claims that he has a model of the climate based on cycles and trends - he does not. He only has a description. And that provides essentially zero predictive power.

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