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Comments 124051 to 124100:

  1. 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.
  2. 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.
  3. 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.
  4. 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.
  5. 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.
  6. 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.
  7. 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.
  8. 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.
  9. 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.
  10. 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.
  11. 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.
  12. 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)
  13. 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/
  14. 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.
  15. 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
  16. 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.
  17. 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)
  18. Is CO2 a pollutant?
    Correction to 131 Gerhard Gerlich and Ralf Tscheuschner
  19. 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
  20. Did Phil Jones really say global warming ended in 1995?
    argh ... "statistically significant growth"
  21. 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.
  22. 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. :)
  23. 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?
  24. 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.
  25. 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.
  26. 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.
  27. 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.
  28. 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.
  29. 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.
  30. 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.
  31. 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.
  32. Did Phil Jones really say global warming ended in 1995?
    Oops, Binomial formula should be 9*0.5^8*0.5^1=0.0178
  33. 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.
  34. 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.
  35. 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.
  36. 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!
  37. 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.
  38. 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).
  39. 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.
  40. Is CO2 a pollutant?
    Bob Armstrong, on the issue of how long CO2 levels remain elevated (your other points having been addressed by carrot eater)... you should consider the ice core record. You dismiss estimates of centuries as ridiculous, but in fact every time there has been a CO2 increase of ~100 ppm (which is about where we are over the pre industrial revolution level) in the ice core records it has taken place over a period of a few thousand years... and then required ~100,000 years to return back down to the previous level. Mere centuries are thus a very 'hopeful' estimate when compared to every past instance for which we have data. It is unfortunate that you are so certain of the validity of your errors. Had you shown a more open mind you might have learned something.
  41. The Dunning-Kruger effect and the climate debate
    HumanityRules at 19:54 PM on 16 February, 2010 Helps to remember that over the long term climate variability one way or another imposed by solar fluctuation will dither widely while more or less exhibiting no net long term change (unless we go forward millions of years). On the other other, what we know of the behavior of C02 when it is illuminated by IR tells us it will impose a steady net increase in the amount of heat energy retained within our atmospheric envelope. I think it's easy to overlook this important difference between one driver of variability (or net variation) and another. what we know now tells us that given a few decades, added C02 in sufficient quantities will always win over solar forcing as a driver of climate change. Also, having noticed a common error creeping into this thread, I'm going to be redundant yet again (r2) and point out that we devote fanatical amounts of engineering expertise to controlling anthropogenic emissions of substances also found as natural constituents of the atmosphere. C0 is a prime example. So it's a fallacy to say that C02 in excessive amounts is not a pollutant. A quick check of the dictionary will help with this.
  42. Did Phil Jones really say global warming ended in 1995?
    suibhne @44 I think I'm right in saying that the CRU have pointed out that they do not generate any original data (records)-- that is, they don't go off to the South Pole, or wherever, to gather readings -- so if Jones said he is not very good at keeping records, it doesn't necessarily mean that he's lost original data, or not know where the original data exists. As I said -- in effect -- earlier, he's a dolphin that's found himself in a pool of sharks. He might be more intelligent and knowledgeable than they are, but his teeth are seriously inadequate.
  43. Is CO2 a pollutant?
    Bob Armstrong: Please review more carefully what Kirchhoff's law actually requires. It should be in any decent physics book. It does not require materials to be grey bodies, which is good because we can clearly see that they are not. Things do have different colors, after all. It only requires that the absorptivity and emissivity be equal to each other at a given wavelength. It does not require either quantity to be constant over wavelength. You can see this emipirically. Look up the emissivity of snow. In the wavelength range where snow might emit (long IR), the emissivity is close to 1. But of course snow is a poor absorber of visible light. Wavelength matters.
  44. Did Phil Jones really say global warming ended in 1995?
    But suibhne, the 2008 paper affirmed the conclusions of the 1990 paper, while lacking the possible flaws of the 1990 paper.
  45. Is CO2 a pollutant?
    suibhne: It isn't a matter of a time delay. The issues are that CO2 radiates back towards the Earth (the surface sees more radiation than it used to), and that the emission that finally makes it out to space is emitted from higher up in the atmosphere, where it is colder (less radiation is leaving the earth system than is arriving, so the system has to warm up). With nitrogen, you get none of that. By the way, CO2 doesn't always instantly radiate a photon as soon as it absorbs one. It can collide with neighboring molecules and thus warm up that pocket of air. But that's still fine; the CO2 will still emit at some rate set by the local temperature. These sorts of things are easily learned about in a textbook that covers radiation transfer in the atmosphere. I suggest simply getting one.
  46. Did Phil Jones really say global warming ended in 1995?
    angusmac @47, see the comments policy for how to post figures. Hopefully you can relate your graph to the discussion.
  47. Did Phil Jones really say global warming ended in 1995?
    Phil Jones may rewrite part of 1990 report. Nature online 16/2/2010
  48. Did Phil Jones really say global warming ended in 1995?
    oracle2world: Is it accurate? 'There has been no warming since 1995' is a very different statement from 'there has been no statistically significant warming since 1995'. In Jones' set there is a warming trend, and every year after 2001 has been warmer than 1995. There has been warming. It is not statistically significant because a certain combination of known noise could recreate that trend in 5%+ of cases. Of course, if you think my stats understanding is wrong, point me to where I can read up and fix it.
  49. Did Phil Jones really say global warming ended in 1995?
    Tom Dayton I Hope that you understand why I remain sceptical about the disputed Chinese readings. No doubt the issue will be examined by each of the two inquiries.
  50. Is CO2 a pollutant?
    Tom Dayton I was in part answering post 119, who if correct with instantaneous absorption and emission of IR, would imply almost that nothing had happened and since IR moves at 3*10^8m/s, then any delay is negligible. Water vapour is still in the atmosphere(in much greater quantities) and is an even better IR absorber. Further conduction from Earth surface by all atmospheric gases plus convection including wind will distribute and even out the Earths surface temperature

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