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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 62001 to 62050:

  1. 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.
  2. 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?
  3. 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.
  4. The Certainty Monster vs. The Uncertainty Ewok
    Josh has a problem with the concept of 'statistical significance', I see.
  5. 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.
  6. 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.
  7. 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.
  8. 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...
  9. 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.
  10. 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.

  11. 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.
  12. Greenhouse Effect Basics: Warm Earth, Cold Atmosphere
    Professor Ray Pierrehumber had an excellent review paper on this topic Infrared Radiation and Planetary Temperature
  13. 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.
  14. 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."
  15. 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.
  16. 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).
  17. 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.
  18. 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!)
  19. 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.
  20. 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.
  21. 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.
  22. 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]
  23. 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.
  24. 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.

  25. 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.]
  26. The Certainty Monster vs. The Uncertainty Ewok
    Now, "the uncertainty Gungan", that I can get behind without reservation. :)
  27. 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.
  28. Radiative Balance, Feedback, and Runaway Warming
    Jose_X - I have replied here.
  29. 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.
  30. Stephen Baines at 03:31 AM on 2 March 2012
    The Independence of Global Warming on Residence Time of CO2
    DM In your exchanges with him, what arguments did Essenhigh use to support his position. I can't imagine a defensible argument. I mean, this distinction between residence time as applied to tracers, and net uptake as applied to total CO2 concentrations and the role of the ocean has been well stablished since Suess and Revelle. As you show it is a simple matter of accounting. This was established science before I was even born!
  31. The Certainty Monster vs. The Uncertainty Ewok
    "...it will curry favour..."
    Pun intended? :-)
  32. Radiative Balance, Feedback, and Runaway Warming
    Can the Scafetta comments (#82-#86 and this one) be moved over with a link back to this thread for reference purposes? I really wasn't interested in analyzing that topic here (or now) and apparently neither is KR. FWIW, I like the gist of this comment http://www.skepticalscience.com/news.php?n=1293#75633 and found KR's http://www.skepticalscience.com/news.php?n=1293#75634 informative.
  33. The Certainty Monster vs. The Uncertainty Ewok
    Dana@16, You know, this really makes me wonder if Curry has even read the IPCC assessment reports. 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. I hope it is not #3. If it is #1 that would be truly embarrassing and reflect poorly on her for talking through her hat. If it is #2, that also reflects incredibly badly on her because it suggests that she is being mendacious and insincere. This is no win for Curry in the realm of scientific integrity. Unfortunately , it will curry favour with the angry mob of fake skeptics who frequent her blog.
  34. Radiative Balance, Feedback, and Runaway Warming
    It seems the webserver garbled the < I had used in comment #84. I'll repeat a large paragraph near the top: I accepted the hindcasting was horrible before 1850. My comment was that no attempt was made to find a "trend line" going back beyond 1850. The model states essentially 1850 < t < 2000 and 2000 < t < 2100 iirc. To hindcast further is interesting but void. The trends are clearly very important to approaching the actual temperature values and were not done. Reusing the linear trend (or had you used the linear and quadratic) as you do is interesting but void. The true older trends likely represent very long term cycles or no real "cycles" at all. [If the analysis were to be extended further, you would probably want to use a large basis set (sinusoids and maybe even polynomials, wavelets, etc) and not just two "trend" curves.] Anyway, without the longer analysis, the short-cycle analysis doesn't become void, but, yes, further back hindcasting will almost surely fail. Now, the short-cycle ....
  35. The Certainty Monster vs. The Uncertainty Ewok
    Composer & Albatross - yes, it seems as though Curry confuses the AGW theory with some sort of CO2-only hypothesis (i.e. only CO2 influences temperatures). This is evident from her quotes in the 'Curry Misrepresents AGW Theory and IPCC Report' section. For example,
    "I find it difficult to think than [solar forcing and natural internal variability] aren’t important in explaining the variability earlier in the century."
    According to the AGW theory and IPCC, they are! This is really basic stuff too - something any climate scientist should fully understand.
  36. Radiative Balance, Feedback, and Runaway Warming
    The browser didn't show me #83 until after submitting #84 (in rep to #82).
  37. Radiative Balance, Feedback, and Runaway Warming
    KR, we might be miscommunicating a little, but I'm sure we are also disagreeing. 1: I accepted the hindcasting was horrible before 1850. My comment was that no attempt was made to find a "trend line" going back beyond 1850. The model states essentially 1850
  38. The Certainty Monster vs. The Uncertainty Ewok
    Dana, Excellent post! It is very disturbing that Curry (chair of the School of Earth and Atmospheric Sciences at The Georgia Institute of Technology) does not understand the difference between a "hypothesis" and a "theory". I am willing to bet that even her students know the difference. Moreover, the options are not mutually exclusive. And I really have a problem with her chracterization of the first option as "IPCC AGW hypothesis". She is playing rhetorical games and polarizing the discussion. The IPCC was not the originator of the theory of AGW for goodness' sakes! The theory of AGW has arisen from the growing body of scientific/theoretical and observational evidence since the days of Fourier and Arrhenius. Moreover, the IPCC does not discount natural external forcings (e.g. solar, volcanic aerosols) nor does it discount internal climate variability/oscillations. In short, her possibilities are nonsensical, incorrect and not not mutually exclusive. Mighty Drunken @12 is correct, she often writes in such an obscure and convoluted style that it makes it almost impossible either understand what she is driving at or to hold her accountable. Curry is also very good at obfuscating and evading being held accountable or correcting glaring errors. Although Dana has very nicely nailed her in his post above. If Curry is paying attention and decides to respond to Dana's post I predict that she will be evasive, argue strawmen and cede nothing. In other words, she will just continue to obfuscate even more. Really, at this point her job is now clear, it is not the at the chair of the School of Earth and Atmospheric Sciences, rather it is being a "Merchant of Doubt" and feeding fodder to the fawning and uncritical fake skeptics who have overrun her blog. For the most part that blog is a cesspit of ignorance and hatred, and is virtually void of any credible scientific and rational discourse. Curry's rapid descent from a once reputable, objective and rational scientist is disheartening and should also be an embarrassment to The Georgia Institute of Technology. It has also not gone unnoticed by her colleagues and peers, including (FWIW) me. And why does Curry's three bizarre hypotheses/theories remind me of Pielke Senior trying the same trick in an opinion piece in the AGU's newspaper EoS in 2009? Hypotheses that were quickly dismissed as nonsensical by eminent climate scientists. Curry needs to be more original than this, but first she must learn how to formulate hypotheses correctly.
  39. The Certainty Monster vs. The Uncertainty Ewok
    Curry is IMO fabricating what the "AGW hypothesis" is all about. Any reasonable construct of the Earth climate system takes into account incoming solar energy, greenhouse gases, inter-play between components of Earth climate system (e.g. ENSO), albedo (from ice or aerosols), and hemispheric insolation (continental position & Milankovitch cycles). As such, an "AGW hypothesis", if such a thing even stands separate from the rest of our understanding of atmospheric physics and climatology, is nothing more than the observation that human-induced increases in greenhouse gases have the expected effect of warming the Earth climate system, moderated or amplified by the other forcings. The surface/satellite temperature records are a tiny part of our understanding of AGW, moderated as they are by the various interchanges of energy within the climate. As such, Curry implying that periods where lower solar insolation, higher aerosol albedo, and interchange of energy within the Earth climate system (e.g. very strong El Nino in 1998 followed by various La Ninas & weaker El Ninos in the 2000s) somehow "refute" any hypothesis at all is, IMO simply mendacious.
  40. The Certainty Monster vs. The Uncertainty Ewok
    Curry's III seemed to me to be an obfuscated way of saying that we don't know anything, or, we don't know enough to make any predictions. We don't have any way of knowing if a coin will come up heads or tails, but we do have considerable knowledge of thermodynamics. If we drill a hole (remove some weight) on the '6' side of a die, we may not be able to predict every roll, but we can predict with confidence that '6' will come up more than it did before. Mike #5, I've had the same thought about time frames for temperatures rather that temperatures within a time frame. Though, I can not argue with the counters that Tom and chriskoz made. My own motivation was driven by my perception that a lot of people seem to think that warming will end at some point, even if BAU continues, and I want a way to make it clear there is no upper limit. At least there isn't one that we care about, because we will pass the point where we can sustain much, if any, population prior to running out of fossil fuels. It is just a matter of when, rather than if, that will happen, if BAU continues. I do have a quibble with the amount of skew in Chris' distribution. It makes sense if the actual warming were only big-O(ln(CO2)), but the feedbacks may make it more linear, at least over the range we care about. Thinking back on Hansen's observation of the increasing coverage of 3-sigma conditions, and looking at the poor harvests that occurred when and where they did, I'm wondering if we can predict a time window when an event like the Russian wheat harvest of 2010 hits a typical agricultural area 1 year in 10 (present day?), 1 year in 5, and so on.
  41. Greenhouse Effect Basics: Warm Earth, Cold Atmosphere
    To correct a slight error in my preceding post, the comparison was between two models, not three.
  42. Radiative Balance, Feedback, and Runaway Warming
    My apologies, my previous comment should have been redirected to the Scafetta Widget thread to stay on topic. Please respond re: Scafetta there.
  43. Greenhouse Effect Basics: Warm Earth, Cold Atmosphere
    dunc461 @41: 1) The observations where made at 17:34 GMT (ie, 11:34 AM in Texas), on Central Time Zone April 22nd, 1969. The surface temperature was 298 K, as measured by a Nomad buoy. The reason for the slight difference between measured and brightness temperatures is that the emissivity of sea water is not exactly 1. The radiosonde data used to set up the model was recorded 100 km from the satellited observation site, and 26 minutes later. 2) As you are obviously very keen on checking the empirical validation of models, you may be interested in this data from Dessler et al, 2008, which compared Outgoing Longwave Radiation observation by the Ceres satellite with three models. The first graph shows the scatter plot of model predictions against observations for the best performed of the three models. Any point falling on the black line shows a perfect match between model and observation. Across the 134,862 observations, the match between model prediction and satellite observation is remarkable. I really wanted to include this plot with the original article as it is far more telling than evidence than the Conrath observation that I did include. In the end, the ease of comparison between the Modtran output, the validation of the wavelength by wavelength comparison, and the need to keep the post reasonably brief mitigated against it. Never-the-less the knowledge of just one paper making comparisons of over 134 thousand observations, each proving the existence of the greenhouse effect really makes me chuckle whenever I see yet another internet blogger masquerading as a skeptic and saying that nobody has ever observed the greenhouse effect. Caption: Figure 1. Scatterplot of 134,862 measured values of OLR against OLR calculated by the Fu-Liou model, both in units of W/m2. The solid line is the one-to-one line. And just for good measure, here is figure 2 from the same paper, comparing accuracy of two of the models over a range of latitudes and surface temperatures. It is not just coincidence of circumstance which allows such stunning predictive accuracy. Need I say it? Radiative transfer physics is settled science! 3) I cannot provide any experimental data showing that "... all energy absorbed is emitted at the same wave number", because the assumption is false everywhere except in lasers. More importantly, it is irrelevant because no such assumption is made either in models of radiative transfer, nor in my article.
  44. Radiative Balance, Feedback, and Runaway Warming
    Jose_X - "The main failure has to do with no reasonable guesstimate for a trend curve going far back. This failure is independent of frequency analysis." I would greatly disagree. There are now about a dozen decent proxy reconstructions of temperature for the last thousand years or so - with no major disagreements. As shown in the comparison here, Scafetta's cycles diverge drastically outside their training interval. They fail in hindcasting, which provides zero evidence that they will succeed in forecasting. Frequency analysis can be helpful in attribution and identification of causal relationships - but it cannot stand alone. You need to follow up by examining the physics. Scafetta performed a very basic frequency analysis on a certain period of one temperature record (not crosschecking against more than one temperature record, incidentally), made some very odd data processing choices (there's a frequency peak at ~4 years, which he does not discuss - but he runs the temperature data through a 4-year smoothing, which eliminates it!), and then fits those frequencies to various astronomic periods without a causal link. That's about as straightforward a case of Correlation without Causation as it gets. Going on the physics, on the other hand (as in Lean and Rind 2008, and in Foster and Rahmstorf 2011), including radiative physics: start with a causal link, examine the time evolution of the forcings for attribution, and from that determine the influence and weighting of various inputs - that has both hindcast and forecast capabilities. And, given that said attributions do account for the evolution of the temperature record given our knowledge of the forcings (within quite small variations), Occam's Razor indicates that invoking mysterious cyclic influences via unsupported linkages is both unnecessary and foolish.
  45. Bob Lacatena at 02:05 AM on 2 March 2012
    Greenhouse Effect Basics: Warm Earth, Cold Atmosphere
    41, dunc461,
    ...all energy absorbed is emitted at the same wave number...
    What do you mean by this?
  46. Dikran Marsupial at 02:01 AM on 2 March 2012
    Scafetta's Widget Problems
    gallopingcamel You are right to say that for Scafetta to gain any traction he will need to develop a plausible mechanism that can explain not only the correlation, but also the strength of the effect. As it happens, I suspect the correlation is not actually all that good, given the number of unconstrained variables he has to play with. All I can say is "good luck with that!" ;o) However, you statement that the IPCC models are examples of curve fitting is simply wrong. GCMs are physical models, not statistical models. They do have some capacity to be tuned, but they are very constrained in this by having to obey the laws of physics programmed into them. Ever wonder why skeptics haven't made a GCM that can explain the observed climate change without CO2?
  47. Mighty Drunken at 01:53 AM on 2 March 2012
    The Certainty Monster vs. The Uncertainty Ewok
    CBDunkerson in post #8 said what exactly what I was going to say. I can't resist pointing it out again though... I find Curry has a certain way with words which manages to take simple concepts and shroud them in convoluted wording which makes you wonder what Curry is really trying to say. Is her convoluted writing related to her (convoluted) thought processes as she tries to please the "skeptics" while not throwing away her scientific credibility? She wrote, "Is it “cherry picking” to start a trend analysis at 1998? No, not if you are looking for a long period of time where there is little or no warming, in efforts to refute Hypothesis I." To reword what I think she is saying, "Is it “cherry picking” to start a trend analysis at 1998? No, not if you are trying to cherry pick a period with little warming." You can't scour the data to look for departures from the hypothesis without taking into account all the other data you just overlooked.
  48. gallopingcamel at 01:53 AM on 2 March 2012
    Scafetta's Widget Problems
    Scafetta has found a strong correlation between planetary motions and short term climate changes. He is all too well aware that he now faces a much harder task. For his theory to gain traction he must develop a plausible mechanism to support his theory. Will he succeed? I for one wish him well as this task may take many years. The IPCC's models are also examples of curve fitting and their predictions will diverge from observations as time rolls by. You complain when Scafetta refines his models yet have nothing to say about the continuing tweaks to the IPCC's models. Here is specific information obtained by comparing leaked AR5 WG1 drafts with AR4. The writer is Alec Rawls in a debate with William (Stoat) Connolley: "I agreed not to quote the AR5 draft, but I did provide a link to the equally ludicrous ratio of 14 to 1 used in AR4. (The exact number is 13.833.) Does Connolley want to call that a lie too? The raw evidence (solar climate correlations vs. CO2 climate correlations) says that the sun is the much stronger driver, yet the IPCC assumes that CO2 has many times the warming effect of solar variation. In for a penny in for a pound apparently. The exact AR5 FOD ratio is 39.857." All of you can check the 13.833 yourselves; it is in the AR4 documents. If you want to confirm the 39.857 number contact me: http://www.gallopingcamel.info/IPCC.htm
  49. Bob Lacatena at 01:48 AM on 2 March 2012
    The Certainty Monster vs. The Uncertainty Ewok
    SRJ, That's an excellent graphic. Looking at it that way sort of puts an exclamation point on the whole "it's stopped warming" meme, simply by demonstrating how noisy, and yet patterned over the recent long term, the climate has been.
  50. The Certainty Monster vs. The Uncertainty Ewok
    # 8 To avoid discussions of cherrypicking, I think a good approach is to fit a local model to the entire time series. That model can then be used to evaluate over which periods the time series show significant changes. And no need to discuss when to start the analysis since all data is used from the time series discussed. Gavin Simpson gives a good introduction to this approach at his blog. The following plot for HadCrut shows in blue which periods had a significant increase: I hope this is not too far off topic.

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