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Comments 123851 to 123900:

  1. It's the sun
    Cliff Oates, can you attribute any physical meaning to your linear weighting function? It looks a bit arbitrary.
  2. Did Phil Jones really say global warming ended in 1995?
    In comparing data, article states: "the areas omitted by HadCRUT are some of the fastest warming regions in the world" If this is about detecting "global" warming, why does regional warming even enter into the equation? If taking "proxy" CO2 measurements from a volcano in Hawaii makes sense, why not apply the same idea for measuring temperature? PS Addressing JonMoseley's comment "To be valid science, one must state that a measurement that is not statistically significant is equivalent to ZERO." Agreed. And personally, with all these spots on communication blunders, one notices that its the reader or audience that is always portrayed as at fault for not understanding or misinterpreting explanations.
  3. It's the sun
    Since sunspot activity is observed for numbers, energy and radiation charistics a complete thermal balance with the earth is a very difficult if not impossible task. I believe that the oceans with their tremendous heat capacity are the key to the earths global temperature. The sunspot numbers count could be used as an indication of the sun's variation from a nominal output. I plotted an a weiighted sunspot number vs time from 1770 to the present. The average sunspot was developed using weighting factors of .4, .3, .2 and .1 for the periods of 0-10, 10-20, 20-30 and 30-40 years before the date of the data point. The resulting plot is consistant with observed long term temperature trends. It would predict the rapid temperature increase of the past century.
  4. Is CO2 a pollutant?
    Suibhne, yes the G&T paper covers EM radiation (incorrectly) in subsequent sections. However, at the start they define a premise that rising CO2 can only be causing warming if it significantly changes the thermal conductivity of the atmosphere as a whole... and then go on for a few pages to show that it doesn't... but then no proponent of the greenhouse effect ever claimed it did because that's not how the greenhouse effect works and G&T are simply, in that section, ignoring radiation physics. In later sections, when they do discuss radiation, they incorrectly dismiss radiative transfer on the grounds that it doesn't conform to thermal conductivity... in essence repeating their original false premise. Again, show me something in their paper which proves that the greenhouse effect does not exist. You insist it is in there, but have repeatedly refused to cite it.
  5. Did Phil Jones really say global warming ended in 1995?
    theendisfar, please follow the comment policy: "No off topic comments. Stick to the subject at hand. If you have something to say about an unrelated topic, use the Search form in the left margin to find the appropriate page."
  6. Is CO2 a pollutant?
    suibhne, i didn't reply to your accuse to Smith on the air molecule behaviour because it's irrelevant to our discussion. Not sure what you are quoting. I assume it was this: "Molecules don't know what the local temperature is, so "hot" molecules happily travel from cold regions to hot ones, and vice versa." If you have followed the whole reasoning, he was contrasting single molecule behaviour with macroscopic "averages". In this sense, it's absolutely correct and does not violate any law of thermodynamics. Indeed, temperature itself is a thermodynamic quantity and can be properly defined only as an ensamble average. Let me quote from a good old book (Terrel L. Hill, "Statistical Thermodynamics", chapter 1, the very first paragraph): "The object of thermodynamics is to derive mathematical relations which connect different experimental properties of macroscopic systems in equilibrium - systems containing many molecules, of the order of, say, 10^20 or more. However useful, these interconnections of thermodynamics give us no information at all concerning the interpretation or explanation, on a molecular level, of the observed experimental properties." With this in mind, we can go one step further and easily see that there's no violation of any law of thermodynamics (as too often claimed in certain quarters) when a molecule radiate a photon toward a warm object simply because thermodynamics does not apply at the single molecule level. A molecule will not choose the direction of the emitted photon, it can not. Still, thermodynamics applies at the macroscopic level, or, in terms of statistical thermodynamics, to the ensamble averages of the mechanical or thermodynamic quantities. So it should come as no surprise that the net overall flux will always be in the right direction.
  7. Is CO2 a pollutant?
    Riccardo Point well made ..For this discussion to go anywhere you need to deal with the actual physics involved. I have to sign off as time presses. But what did you think of Smiths howler?- surely we can agree on that.
  8. Is CO2 a pollutant?
    CBDunkerson You imply by saying ... we must look at two factors; thermal conductivity and isochoric thermal diffusivity..that G&T do not deal with EM radiation. Most of their paper deals with em radiation! To selectively misquote and then prove a point will not further anyone's understanding.
  9. Is CO2 a pollutant?
    suibhne, you're actually missing that many climatologists have a PhD in Physics. You are also missing that one needs to know, for example, atmospheric physics as well. As i'm sure you may notice, i've actually read several opinion including Staples's and commented on the physics behind it. For this discussion to go anywhere you need to deal with the actual physics involved, not just use this sort of propaganda-based claims like "climatologists need to study physics".
  10. Is CO2 a pollutant?
    Tom Dayton Looked at your long list of refutations-two! The AP Smith one(above) and a German one that Eli Rabitt was going to use but since apparently has backed off) Interestingly at the end of the blog Eli asks for help from someone who knows some Physics ..Eli thinks it good that anyone writing on climate understand basic thermo. Other than that a passing acquaintance with the data and the basics helps a heap... Riccardo You seem to have looked at the AP Smith website, what a howling mistake he makes about gases in a gravitational field! At first I thought it was a hasty slip up but he seems to be persisting in it. If you have any basic knowledge of Physics you will know its embarrassing. Further you state... "This is really graduate level climatology." Perhaps they should teach more Physics in the climatology classes and elementary mistakes will be reduced. I would recommend anyone with an interest in this topic to read the A P Smith blog as the arguments are teased out and positions clarified.
  11. There's no empirical evidence
    Argus, did you ever imagined that there's not just CO2 around? Did you noticed that you (as opposed to the climatologists) are using the wrong logic that because there has been warming in the past (not anthropogenic for sure) current warming can not be due to CO2? Did ever read a general climate paper where all of what you cite ("e.g. the oceans warm up, more water vapour in the atmosphere, more clouds, less radiation reaches the surface") are give the due importance? Can you really belive it's so easy to dismiss a theory that has passed through decades of scientific scrutiny before being widely accepted?
  12. Is CO2 a pollutant?
    Suibhne, International Journal of Modern Physics B? Nope, never heard of it. Not surprising given its 2008 impact factor of 0.558. Still, an actual indexed scientific journal published G&T. How very sad for them. I already listed some of the paper's blatant flaws. I note that you still refuse to cite a single passage in support of your claim that it disproves the 'greenhouse effect'. So hey, allow me; In section 1.1 G&T assert that in determining whether CO2 is warming the planet we must look at two factors; thermal conductivity and isochoric thermal diffusivity... which are basically factors for determining the transfer of heat between molecules. What G&T leave out is that molecules can also be heated by electromagnetic radiation. In short, they start from a first principle of ignoring the central cause of greenhouse warming. Their claim would also mean that heat from the Sun only reaches Earth by being conducted from one molecule to the next... NOT in the form of EM radiation. Which is, of course, pure idiocy. That's page one. It goes downhill from there.
  13. Is CO2 a pollutant?
    suibhne, Staples, in turn, has his share of misinterpretation of how the radiative balance of the surface-atmosphere system works. Trying to falsify the atmospheric greenhouse effect just because it depends on the number of, he thinks, arbitrary layers is really straw man. Is this supposed to be the backfire? This is really graduate level climatology. But anyway, "It has been widely refuted in many ways" read those many others if you don't like that one and also look at the basic mistakes in Gerlich paper an average physics student will notice. Hint #1: wrong application of the second law of thermodynamics. Hint #2: the radiative balance and net fluxes Hint #3: thermal conductivity of the atmosphere Don't need to continue, there's clearly much more. Any interested reader will easily find information over the internet or find them by himself in the paper. The real question here should be how come that such a pedantic and aggressive (they talk about "scienti c fraud") paper made it through peer review in Internation Journal of Modern Physics.
  14. There's no empirical evidence
    David Rourke (on 3 December, 2009) is right, and the responses to his posts are wrong! He points out a flaw in the argumentation. Faulty logic should not be used to prove the AGW theory. Those who opposed his criticisms did not understand basic logic. The assertion 'A implies B' says that if A occurs then B also occurs, but it does not prove that B is always caused by A. If we observe B, we cannot be sure that the reason is A. Example: We know that the burning of tyres causes black smoke, but if we see black smoke in the distance, we do not know that it comes from tyres burning. There could be other sources. An example from using climate data: there was a major period of continuous global warming from 1900 to 1940. This would seem to prove that our grandparent generation burned maybe even more oil and coal than we have done the last 50 years, since global warming obviously did occur, and since increased CO2 in the atmosphere is known to cause global warming. But they did not! They added considerably less CO2 than we do now. So there must be other explanations to global warming that have to be considered. By the same token there could be other mechanisms in action that counteract the effect of the (documented) increase in CO2, e.g. the oceans warm up, more water vapour in the atmosphere, more clouds, less radiation reaches the surface - result: global cooling or return to status quo.
  15. Is CO2 a pollutant?
    suibhne said, "Until a peer reviewed refutation of it appears then it must be considered to be the best Physics take on the topic. That's the way it works in science I'm afraid." So I take it that means that you accept that all other publications since that time are now the best physics, replacing G&T? They are, after all, newer. This is silly.
  16. Is CO2 a pollutant?
    I knew this was headed towards G&T. Sometimes a paper is just so bad in elementary ways, it isn't worth the trouble of a formal response. Among many errors (and much misplaced arrogance, and irrelevant discussions of glass greenhouses), they seem to think there's a violation of the Second Law in the greenhouse theory. There is not. Heat always flows the right way, in the theory.
  17. Is CO2 a pollutant?
    suibhne, the Gerlich and Tscheuschner article has been thoroughly discredited in multiple places by multiple people. One list of those is at RealClimate.
  18. Is CO2 a pollutant?
    CBDunkerson The peer reived article you inquired about G. Gerlich, R. D. Tscheuschner: Falsification Of The Atmospheric CO2 Greenhouse Effects Within The Frame Of Physics. International Journal of Modern Physics B, Vol. 23, No. 3 (30 January 2009), 275-364 Perhaps if you have any specific criticism after reading the paper you can set these out in a formal way.
  19. The Dunning-Kruger effect and the climate debate
    Having only just heard of the D-K effect, and not yet read their paper, and obviously very prone to it myself, I'm going to postulate the existence of a reverse D-K effect that might affect a whole field of study. It seems possible, and I'm not even slightly suggesting that this is true with climate science, that whole subject areas attract the less academically able, and that the individuals in this area see themselves as good academics with sound reasoning skills just because they are as good as their close colleagues.
  20. Is CO2 a pollutant?
    Suibhne wrote, "Until a peer reviewed refutation of it appears then it must be considered to be the best Physics take on the topic. That's the way it works in science I'm afraid." No... it really isn't. As has been explained on this site before, 'peer review' does not mean 'proven true' or even 'best available science'. What it is SUPPOSED to mean is that the text has been reviewed to identify and eliminate any obvious errors and conforms to standard scientific practice. You still haven't said where it was published, but it can't have been in any journal with any kind of solid reputation because that study is just complete nonsense. Note that I cited specific errors and failings in the text and you respond only with an unfounded assertion of the paper's 'truth'. Again, CITE where exactly it disproves greenhouse warming. You claim it does this, so you must be able to show where.
  21. The Dunning-Kruger effect and the climate debate
    What do you call the effect when you find you have more experience, wisdom, insight, brains, etc., than anyone else around you? It can be very lonely "up" here on Mt. Olympus.
  22. The Dunning-Kruger effect and the climate debate
    I have to thank the editor for responding to my comment. But again I have problems with the graph. The quantity being reported is now gigatonnes of CO2, not atmospheric concentration. And the time scale is shrunken even more, now going back to 1000AD. Secondly it is comparing a hypothesis with a fact. There is no way to distinguish CO2 emitted by humans from CO2 occurring from non-human activities. Second, the amount of CO2 emitted by humans graphs follows the global population graph. But the global warming hypothesists tend to discount CO2 emitted by humans because it's source is from plants that sequester CO2 and is therefor part of a natural loop that neither increases nor decreases CO2 concentration. I think the graph meant to say, "CO2 increase due to human burning of hydrocarbons previously sequestered from the atmosphere when CO2 levels were much higher than today." I think this somewhat touches on what Ned and Marco said too. There is agreement than that previous CO2 levels did not lead to a runaway global temperature rise, but a limited rise and that driving by the sun has a huge influence on global temperature. We may be seeing that at present. We'll know as the next solar cycle revs up as it is now. If there is a limit to how much CO2 can raise global temperatures we can breath a sigh of relief. There is such a limit in science as CO2 just closes the lower temperature window to re-emission of thermal radiation from earth's surface. So as global temperature rises CO2 has less of an effect on greenhouse warming because the wavelengths of the thermal IR are higher than the notch effect CO2 has. In other words as the temperature rises CO2 becomes transparent to the emitted radiation and therefore becomes less of a greenhouse gas. The Dunning-Kruger effect brings to mind what writers thousands of years ago already recognized. "How precious are thy thoughts unto me, O God! how great is the sum of them! If I should count them, they are more in number than the sand..." Psalm 139:17-18 In other words the writer was admitting he was unskilled and God had skill.
  23. Is CO2 a pollutant?
    Riccardo The "refutation" you cite is a non peer review paper by Arthur P Smith If you go to his own websites you will find that this attack have backfired. A contributor to this threads has been Fred Staples a Physicist whose was responsible for heat transfer in a nuclear power plant. He patiently and with good manners demolishes this attack because his understanding of thermodynamics is far superior. If you Google Arthur p Smith, not spaghetti,the arrogance of physicists, you can catch up with his thread. Currently Smith has boxed himself into a corner by saying that a gas molecule moving upwards in the Earths Gravitational Field would remain at a constant temperature. This as any high school physics student knows is rubbish. Typical High School Physics Question is" using the kinetic theory of gases calculate the rms speed of a N2 molecule at STP and if this molecule moved vertically upwards how high would it get, what would happen to the temperature as it went higher" (Answers 517m/s,13.6Km,drops constantly)
  24. Did Phil Jones really say global warming ended in 1995?
    Tamino on OpenMind did a post on how much time was needed to establish a trend from GISS data. Tamino really knows his stuff! http://tamino.wordpress.com/2009/12/15/how-long/
  25. Is CO2 a pollutant?
    suibhne, Gerlich and Tscheuschner paper was originaly an arxiv papaer in 2007. It has been widely refuted in many ways (for example here). It took two years to get published somewhere but it's essentially the same. There are two ways of refuting a paper, comment on it or ignore it. Now the latter will suffice.
  26. Is CO2 a pollutant?
    # CBDunkerson 133 I'm afraid it was published in a Physics journal which is perhaps why you haven't heard of it. Until a peer reviewed refutation of it appears then it must be considered to be the best Physics take on the topic. That's the way it works in science I'm afraid. Just repeating to yourself "it is rubbish" ten or more times will not alter the situation
  27. Is CO2 a pollutant?
    That G&T stupidity actually got published? In a real scientific journal? I'm gonna guess GRL, E&E, or something I've never heard of before... and probably never will again. I remember when they first self published it a couple of years ago. After about 50 pages it got to be too much, but I remember they couldn't figure out a simple effective temperature equation (objecting that factors of 0.7, which comes from albedo, and 0.25, from 1/r^2, were just 'made up'), insisted (repeatedly ad nauseum) that since the 'greenhouse effect' does not work the same way as an actual greenhouse it cannot exist, and claimed that Fourier and Tyndall never said anything about gases warming the planet - that was just 'made up' by Arrhenius. It is a work of pure denial... complete with lengthy screeds against 'evil warmists'. It reads like one of Bob Armstrong's 'everyone who has ever studied science other than me is an idiot' posts rather than any kind of scientific study. Please, if you think there is ANY validity to that paper, quote or summarize some argument from there which ISN'T completely ridiculous.
  28. Dikran Marsupial at 20:13 PM on 17 February 2010
    Did Phil Jones really say global warming ended in 1995?
    Tobjoyce@53 says: "Statistical significance is given usually as a p-value which is the probability that the data occurred by chance alone." no! The p-value is the probability of observing a statistic as extreme as that observed, assuming the null hypothesis is true, by chance in a large number of independent replications of the experiment. That is not the same as the probability that *this* data occurred by chance (as that would be the probability that the null hypothesis is true). Indeed frequentist approaches fundamentally can't answer such questions, they can only make statements about things like the proportion of events of a particular nature in a large number of replications of an experiment. There is nothing wrong with that per-se, but it is important to view the result of the test within the statistical framework in which was conducted, or misunderstandings will arise. JonMoseley (3) made essentially just that error, treating the lack of statistical significance as demonstrating the null hypothesis to be true (or at least highly likely to be true), and then mistakenly claiming that the models were wrong for not also supporting the null hypothesis (not that he was right about that either). Anyway, don't listen to me, I am a Bayesian so I may have strong prior beliefs about frequentist significacnce testing! ;o)
  29. Is CO2 a pollutant?
    Correction to 131 Gerhard Gerlich and Ralf Tscheuschner
  30. Is CO2 a pollutant?
    carrot eater 129 The peer reviewed Gerhard and Tscheuschner paper removed the "Greenhouse Effect" (which labelled co2 as a threat to humanity) from the realms of serious scientific study. Since it was published in March 2009 there has been no peer reviewed refutation of their position If a successful challenge to G&T is to happen I would expect it to come from say a Professor specialising in Heat Transfer Thermodynamics
  31. Did Phil Jones really say global warming ended in 1995?
    argh ... "statistically significant growth"
  32. Did Phil Jones really say global warming ended in 1995?
    As Joe Romm puts it the problem is in the question, something like asking "are you still beating your wife?". If you by instinct answer "no, of course" you're admitting that once you did. Tamino gives another example. You have been measuring a child's height for years to follow his growth. If asked if you can prove that there has been a stistically significant growth in the last week you have to say no, so the child is not growing any more. What i want to say is that there is no meaningfull answer to a meaningless qustion but reformulating it.
  33. Is CO2 a pollutant?
    For anyone who wants to see a reasonably detailed deconstruction of Bob Armstrong's arguments, I recommend his and my exchange at S&R here, down toward the bottom: http://www.scholarsandrogues.com/2009/11/20/climategate-not-likely/ Furthermore, I dealt with the bulk of his arguments using physics (complete with the math, calculations, derivations, etc.) in three documents also available at S&R: http://www.scholarsandrogues.com/wp-content/uploads/2009/11/BobArmstrong.pdf http://www.scholarsandrogues.com/wp-content/uploads/2009/11/emissivity.pdf http://www.scholarsandrogues.com/wp-content/uploads/2009/11/Venus.pdf Bob never responded after I posted the last two .pdfs, yet here we find him making some of the same wrong claims that I am pretty confident I disproved. The only argument he made at my site that I didn't take on is his MgO sphere example from above, but I'm pretty sure that he's misunderstood it badly. I think that the power in the interior of his hypothetical room should be constant, so the MgO ball ends up being the same temperature as the room no matter what it's albedo is (power density drops as r^2 as you leave the walls of a spherical room and move toward the center, but the area of the sphere drops as R^2 too, leaving the power constant). But I didn't prove it rigorously with calculus. If anyone reads those docs and sees major flaws in my math, please let me know. I'm planning on using the Venus doc as a baseline for a "debunking this bad argument" post at some point (or maybe John can. :)
  34. Did Phil Jones really say global warming ended in 1995?
    That's a very good point, GFW. Perhaps Phil Jones, in his reply, should have said "there is no statistically significant change from the previously established warming trend". Easy to second-guess in hindsight, though, isn't it?
  35. Did Phil Jones really say global warming ended in 1995?
    I just realized what the correct rebuttal is to people who choose short recent time periods and say things like "you can't reject the null hypothesis, so there's no statistically significant warming". Here's the thing. The upward linear trend since the mid 70s (30+ years) is known and is easily shown to be statistically significant. So the null hypothesis for short time periods near present is "that rate of warming continues". And guess what? There is no cherry pick that will allow anyone to reject *that* null hypothesis. We can easily quantify what it would take to reject continued warming. When that condition is met (and I'm not expecting it) then climatology would have some 'splaining to do. But only then, and it sure isn't likely.
  36. The Dunning-Kruger effect and the climate debate
    KLR @ #78: There is a nice graphic presentation of the consensus on this issue. John has it in this article. Seems very clear to me.
  37. Did Phil Jones really say global warming ended in 1995?
    Again, Arkadiusz Semczyszak, you are mistaken. If you take a look at the GISS data, you'll see there is a very good relationship between the apex & nadir of each solar cycle & the warmest & coolest years within that cycle. Even if that were not so, the 2000-2009 portion of the current cycle was by no means normal-its the deepest solar minimum in over a century-& it lasted around 4 years-yet still temperatures moved generally upwards. Lastly, it doesn't alter the fact that, beyond the normal cycles, solar activity has been trending downward for the last 30 years, yet temperatures have been trending upwards over this same time period. I've seen several papers which conclude that the correlation between solar activity & deltaT ceased at least as early as 1979 & possibly as far back as 1950.
  38. The Dunning-Kruger effect and the climate debate
    Someone should have a graphic presentation of the consensus on this issue. Recently I saw a graph illustrating the number of climatologists signing onto some anti-AGW petition versus those declining, it was quite striking. More of that, please. Show just how much of a minority your opponents are, and how lopsided the qualifications of the respective camps are. logicalscience.com is a good start but you need to direct your efforts towards the unlettered, to say nothing of educated people who lack the time to read page after page of documents attempting to reach a conclusion. There needs to be a clearinghouse for links to info of this sort as well. The extant resources I find lacking in various ways, it should be a dedicated endeavor, rather than expending enormous amounts of time debating people with irrational emotional attachments to political postures, which accounts for the bulk of the anti-AGW sentiment in the public, not any true spirit of scientific inquiry. You may enjoy attempting to knock sense into random heads but we are really wasting our time here arguing with these people.
  39. Did Phil Jones really say global warming ended in 1995?
    Steve L. @#59 "As D.Marsupial says in #24, one fails to reject the null hypothesis; one doesn't accept the null hypothesis" Yes, you are right; that is the way I should have put it.
  40. Did Phil Jones really say global warming ended in 1995?
    When Steve L wrote "if the effect size and sample size are small relative to the noise in the system," he was referring to statistical power.
  41. Did Phil Jones really say global warming ended in 1995?
    The important question about trends is not about statistical significance, which is very much dependent on the methods used, but of stability. Starting with the latest records, and extending the observation period backwards, does the trend coefficient stabilize in a reasonable time, and on what? Trends for shorter periods may very well be statistically significant - that is mostly a question of fluctuation, noise, level. But are they stable? The 1995-2009 GISS trend of ca 0.15 degC/decade seems to be a relatively stable figure. To get much higher values, you have to cherry-pick observational series, and likewise, to get much lower values, you have to omit a lot. Interestingly, the GISS and UAH trends are very close to each other. Of course, there is really no scientific significance associated with the 0.05 level, it's just one practical about reporting and one formal about what we, by convention, may report. Only great fools would disregard a result at the 0.06 level because "it is not significant" - after all, it's 94% chance there is something there. Likewise, as you would get a 5% significant result by chance one in out of 20 trials, you really can't "trust" a randomly chosen 5% result. It's all about looking at the whole picture of information. And when we can get results as significant as we like just by extending the observation period a little, any talk about "null hypothesis acceptance" her may be utterly misleading. The rank viewpoint may be useful, but I think it should be used carefully in simplistic statistical modeling: If, for instance, all the last 10 years are among the top 30 on record (I haven't checked that, just an illustration, but it's not too far off), it's far too early to talk about "cooling", even if we may have entered into a new period, with new trends. We just have to await the further development.
  42. Did Phil Jones really say global warming ended in 1995?
    Re: TobyJoyce in #55 -- it's good for you to provide a basic summary (and I look forward to the one John Cook promised in #19). However, I'd like to take issue with your last statement that "the null hypothesis would be accepted." As D.Marsupial says in #24, one fails to reject the null hypothesis; one doesn't accept the null hypothesis. This sort of terminology is adopted because the null hypothesis (hypothesis of no difference) may be statistically indistinguishable from the alternate hypothesis if the effect size and sample size are small relative to the noise in the system.
  43. Did Phil Jones really say global warming ended in 1995?
    Oops, Binomial formula should be 9*0.5^8*0.5^1=0.0178
  44. Did Phil Jones really say global warming ended in 1995?
    There is another way we can look at this borrowed from quality assurance methods. It is a bit crude, but it looks to me like 8 of the last 9 points in Figures 1 and 2 are above the mean of all the points (which seems to be about 0.35). If we set the probability of being above the mean to be 0.5, then it just an application of the Binomial Theorem - the probability of that happening is 9^0.5^8*0.5^1 = 0.0178, which makes it significant at the 5% level. The deduction is that there is an "upward shift in the mean" between the start of the sequence of points and the end. In QA, this is called a "run above the mean". If you take all the points, 9 are above the mean & 6 below, which has a 0.1527 probability.
  45. Is CO2 a pollutant?
    suibhne If your complaint is going to be based on the Second Law, then rest assured that nowhere in the system is there a net flow of heat from a cold point to a warmer point. Heat is always flowing in the correct direction.
  46. Did Phil Jones really say global warming ended in 1995?
    There seems to be a bit of confusion about "statistical significance". Statistical significance is given usually as a p-value which is the probability that the data occurred by chance alone. If an hypothesis has a low enough p-value, we tend to accept it because the evidence (data) is therefore unlikely to be by chance alone. Ronald Fisher, who introduced p-values, set 5% and 1% as threshold values for significant *"highly significant" results. But there is an element of subjectivity about p-values. Suppose your p-value is 0.0505? Is that significant? Some practitioners suggest just publishing the p-value and then deciding. Jones did not publish his p-value but it must have been less that 10%, or quite close to 5%. The null hypothesis in this case is that the slope of the fitted trend line through the points = 0. If the 95% confidence interval for the slope contained 0,then the null hypothesis would be accepted.
  47. Is CO2 a pollutant?
    suibhne, you believe Tom Dayton and carrot eater are laboring under a misunderstanding, but you don't explain how. Could you do that? Thanks!
  48. Is CO2 a pollutant?
    Tom Dryton and carrot eater It seems to me you are in need of some grounding in thermodynamics. Could I recommend Equilibrium thermodynamics by C.J.ADKINS The mechanisms you describe seem contradictory and unphysical.
  49. Did Phil Jones really say global warming ended in 1995?
    Tom Dayton,John Russell Read the Nature interview very revealing!..... and a reply from Keenan, D. J. underneath article. Energy & Environment, 18, 985-995 (2007).
  50. Is CO2 a pollutant?
    Here's an augmentation of CBDunkerson's response regarding CO2 "lifetime": CB used the correct phrasing "how long CO2 levels remain elevated," because that is what matters--the total amount of CO2, not which individual CO2 molecules make up that level. Often the blogosphere uses the ambiguous term "CO2 lifetime." That can be taken to mean "duration of an individual CO2 molecule's residence in the atmosphere," which is irrelevant. If one molecule (Lucy) is absorbed out of the atmosphere, with the consequence that that particular absorbing mechanism now cannot absorb a different molecule (Ethyl) which newly has entered the atmosphere, then the level of CO2 has not dropped due to the absorption of Lucy. Lucy and Ethyl can play tag forever, with one at a time being in the atmosphere, with the consequence that the level stays constant. What matters is the balance between emission and absorption, from all sources and sinks. When emission increases faster than absorption, the level in the atmosphere increases, despite the constant swapping of individual molecules.

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