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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 23151 to 23200:

  1. Naïve empiricism and what theory suggests about errors in observed global warming

    Tom Curtis @14

    I accept paragraph one. I also often comment for the wider readership on various subjects, rather than just to convince the person I'm replying to.

    Regarding the rest of your comments in paragraphs two and three, I accept one single experiment would not falsify a theory, as all experiments are based on theories regarding instruments and methods, of which we cannot be 100% certain.  But how many experiments would you need? It seems the same point applies over and over. One could argue we have 'enough' experiments,  and they have strong underlying theories, but all that is rather subjective.

  2. Naïve empiricism and what theory suggests about errors in observed global warming

    nigelj @12, first, I certainly had no intention to "talk down to you".  In everything I write at SkS, I am always aware that this is primarilly an educational cite, whose readership is much larger than the number of people who commentate, and who cannot be presumed to have a significant education in science, still less philosophy of science.  As a result I am inclined to go back to basics, to spell out things in small steps, and to link to sources of technical terms, even when I know that is not necessary for the person to whom I directly respond.  If that has, in this case, created an impression of condescension, I am sorry.

    That said, however, your response shows that you have not appreciated, or do not agree with my fundamental point.  Quoting Lakatos again, "There are no such things as crucial experiments".  No single experiment can ever falsify a theory by itself, still less a scientific research program.  That is because every experiment uses instruments that are presumed to operate in a particular way based on yet other theories, so that the "failure" of the experiment calls into question not just the one theory, but all theories involved in the design of the instruments.  An experiment, together with an assessment of the relative robustness of the theories under test and involved in understanding the instruments may lead to the dropping of a particular theory as falsified, but that assessment itself involves knowledge of the reliability of the different theories in other experiments, not to mention assessments of their relative cohesion and simplicity.

    One experiment may act as the final straw for a given scientist, or a large number of scientists; but if other scientists continue to espouse the theory, that does not thereby make them irrational.

  3. Naïve empiricism and what theory suggests about errors in observed global warming

    I'd modify Victor's "And it is important that a theory can be proven wrong, that it is falsifiable. If not, you did not describe the theory clear enough." I would make that "...can have the balance of evidence showing it wrong," rather than "proven." Always there are assumptions and uncertainties that come along with evidence both theoretical and observed, which prevent absolutely proving anything either true or false.

  4. Naïve empiricism and what theory suggests about errors in observed global warming

    Tom Curtis @11

    Yes I agree that Einsteins "alleged" quote on experiments could be manipulated by climate deniers. However your point seems a little pedantic to me, as we are always going to get this sort of thing from deniers. For example it's well known that a theory can also be falsified by new information or discrepancies, and deniers can point at this as a general belief that any reputable scientist would subscribe to. Sadly denialists will try to find some so called new information, and missunderstand it or twist it. 

    And basically one experiment could falsify a theory, but it would have to be a convincing experiment replicated etc. The more compelling the theory the more convincing the experiment would have to be.

    I was really just making the point that deniers want 100% proof of climate change theory, when this is a strawman argument because 100% proof is impossible in any major theory of science. Proof belongs to mathematics.

    Please dont talk down to me about problems of observations. I mentioned the same thing in my post. Try to read past line one. 

    I'm also well aware that a complex but well established theory like climate change is not falsified by some problem with some specific aspect. Although the usual suspects would swear black and blue it is.

  5. Naïve empiricism and what theory suggests about errors in observed global warming

    nigelj @10, it matters because AGW deniers and other pseudoscientists latch on to the Einstein quote and insist that all the entire theory of AGW (or evolution, or the safety of vaccines) has been overthrown by their one preferred experiment that they are probably misinterpretting in any event.  

    Neither of the actual quotes from Einstein (@2 above) supports this sort of naive falsificationism.  It is possible from the second of the quotes that Einstein was a naive falsificationist, but that is not consistent with generally deep thinking about philosophy of science.  Certainly, Popper, who Einstein highly praised, was not a naive faslificationist, saying:

    "Every test of a theory, whether resulting in its corroboration or falsification, must stop at some basic statement or other which we decide to accept. If we do not come to any decision, and do not accept some basic statement or other, then the test will have led nowhere. But considered from a logical point of view, the situation is never such that it compels us to stop at this particular basic statement rather than at that, or else give up the test altogether. For any basic statement can again in its turn be subjected to tests, using as a touchstone any of the basic statements which can be deduced from it with the help of some theory, either the one under test, or another. This procedure has no natural end. Thus if the test is to lead us anywhere, nothing remains but to stop at some point or other and say that we are satisfied, for the time being."

    (See my discussion here.)

    This can be illustrated by Einstein's general theory of relativity, and his cosmological constant which he once described as his greatest mistake, but which is no being rehabilitated.  In essence, at the time Einstein formulated the general theory (1915), astronomers believed that the universe consisted of just one galaxy.  That theory was not disproved until 1923, by Erwin Hubble.  Because a single galaxy is necessarilly non-expanding, Einstein felt a need to modify his theory so that it predicted a non-expanding universe to fit the "observations" of the astronomers.

    It may be objected that the non-existence of other galaxies was itself a theory, not an observation, but that misses the point.  All observations are theories, if often simpler theories - unless we restrict the term to descriptions of the instensity and relative spacing of various colours, sounds, tastes, smells and sensations.  Even the "observation" that the pressure on my fingertips is caused by the cup I can see in my hand goes well beyond the strict data and represents the very often believed, but potentially wrong (at least from a logical point of view) theory of the existence of an external world.  Indeed, sometimes such "observations" are falsified in our own experience, as when we have a dream that accounts for a phenomenon in the dream, which upon waking we discover was a real phenomenon intruding into our sleeping mind.

    If that is getting too philosophical for you, Victor's example @9 well illustrates the point that "observations" are not just given.  They come with certain assumptions which themselves can be falsified.  In a similar vain, Eddington's famous observations that "confirmed" general relativity included observations from two instruments.  Those from one more closely matched the predictions of General Relativity, while those from the other more closely matched Newton's theory, as interpreted at the time.  The later were discarded as inferior, but clearly no simple falsification of Newton was involved.  To further complicate things, the discrepant observations were later (1979) reanalyzed as being more in agreement with General Relativity.

    Further, as Lakatos said, all new theories are born in a sea of anomalies (ie, of "observations" that contradict the theory but that are put aside in the short term in the hope that later analysis will clear them up).  Elsewhere he wrote:

    "In the distorting mirror of naive falsificationism, new theories which replace old refuted ones, are themselves born unrefuted. Therefore they do not believe that there is a relevant difference between anomalies and crucial counterevidence. For them, anomaly is a dishonest euphemism for counterevidence. But in actual history new theories are born refuted: they inherit many anomalies of the old theory. Moreover, frequently it is only the new theory which dramatically predicts that fact which will function as crucial counterevidence against its predecessor, while the ‘old’ anomalies may well stay on as ‘new’ anomalies."

    (Foot note 14.  It is highly recommended that you read the whole article.)

  6. Naïve empiricism and what theory suggests about errors in observed global warming

    Does it even matter precisely what Einstein said? We all get the general theme of what he was saying, which is perfectly reasonable, namely that you can't be 100% certain about some theory, or 100% prove a theory. In fact proof really only applies to mathematics.

    Maybe one day we would have 100% certainty. However at "this stage" of human development we can't really be 100% for numerous different reasons. For example we can't be certain observations are always 100% correct, and we cant be 100% certain things like inductive logic would always produce the right answer.

    But we can be about 99% certain that various theories or laws are correct, at least in a certain range of definable conditions. For example we would have to be at least 99% certain of the theory of evolution.

    This is the best we can do, some level of certainty. Humanity either bases it's decisions on science and levels of certainty, or mysticism. Theres no other alternative.

    Sometimes we just have to accept some things are certain for all practical purposes. The world is 99.999% certain to be a sphere (or oblate spheroid whatever the correct shape is). It would only be flat if we were all living in some "Matrix" like the movie, and being deceived into thinking it was a sphere. Chances of this are not high. 

  7. Naïve empiricism and what theory suggests about errors in observed global warming

    matematik:

    "Even if Einstein didn't say "No amount of experimentation can ever prove me right; a single experiment can prove me wrong", is there still truth or value in the statement?"

    There is a core of truth in this. You cannot prove that a theory is right. Certainty is the realm of religion.

    And it is important that a theory can be proven wrong, that it is falsifiable. If not, you did not describe the theory clear enough.

    However, actually showing a theory to be wrong is normally not just "one experiment". Because one experiment always tests a multitude of theories. In case of the faster than light neutrinos, a theory that was tested was that the cable was attached well to the instrument. That turned out to be the theory that was refuted and not the theory that nothing can go faster than light.

  8. Naïve empiricism and what theory suggests about errors in observed global warming

    Even if Einstein didn't say "No amount of experimentation can ever prove me right; a single experiment can prove me wrong", is there still truth or value in the statement?

  9. State of the Climate 2015: global warming and El Niño sent records tumbling

    nigelj @ 5

    Thanks for clarifying the issue for me

  10. One Planet Only Forever at 01:05 AM on 26 August 2016
    Naïve empiricism and what theory suggests about errors in observed global warming

    In my previous comment I had not included another group that always needs "excuses". The fans of full freedom of everyone in Free Market Capitalism.

    The understanding and explanations of what is wrong with allowing everyone to be free to do as they please lead to requirements for the advancement of humanity that are contrary to the interests of many people who developed a taste for getting away with benefiting from activities that can be understood to be unacceptable, activities that all of humanity can not be allowed to develop to enjoy, activities that even a portion of humanity cannot continue to benefit from indefinitely on this amazing planet, activities that have to be fought over by people trying to be the ones who get to enjoy the most personal benefit, fighting that has to be "excused".

  11. One Planet Only Forever at 00:56 AM on 26 August 2016
    Naïve empiricism and what theory suggests about errors in observed global warming

    "The main blog of the mitigation skeptical movement, WUWT, on the other hand is famous for calling trying to understand the reasons for discrepancies: "excuses""

    The use of the term "excuses" by the likes of WUWT can be "Understood and Explained".

    Many people who know they behave unacceptably "excuse" their behaviour by claiming everyone else is like them. If they did not have a way to "excuse" what they can understand is unjustified they would feel obliged to change their thinking, beliefs and behaviours.

    Of course, those who are guided by the pursuit of better understanding with an honourable objective, like “the advancement of humanity to a lasting better future for all”, are open to constantly changing their minds, but only when it is justified by the accumulated evidence (and since there is never likely to be evidence regarding spiritual matters they can maintain a scientific way of thinking while maintaining spiritual beliefs).

    As Einstein said "Science without religion is lame, religion without science is blind."

    So it is possible to "understand and explain" why the likes of WUWT resort to the term "excuses" rather than "explanations". And it is also possible to understand the high number of fundamentalist religious adherents who are in the habit of using “excuses” for their preferred beliefs. But that "understanding and explanation" does not "excuse" what they desire to believe and try to get away with doing.

  12. meher engineer at 16:34 PM on 25 August 2016
    Katharine Hayhoe on Climate and our Choices

    well said, DR Hayhoe. Have circulated the video widely.

  13. One Planet Only Forever at 14:28 PM on 25 August 2016
    Naïve empiricism and what theory suggests about errors in observed global warming

    There are other things to keep in mind regarding Einstein quotes.

    "The Great Thoughts" compiled by George Seldes and published in 1985, includes the following footnote regarding the Einstein quotes included in it:

    "All quotes dated up to October 1954 were acknowledged and corrected by Dr. Einstein, who read the Mss. and replied: "Many things which go under my name are badly translated from German or are invented by other people." Among the paragraphs Dr. Einstein deleted, for example, was his supposed reply "There is no hitching-post in the Universe" to the request for a "one-line definition of the theory of relativity" made by a boat-train reporter the day he arrived in America (December 30, 1930)."

  14. Naïve empiricism and what theory suggests about errors in observed global warming

    Over at Victor Venema's blog, the comment I liked best was the one that said:

    "As Einstein himself noted, "I never said half the crap they say I did on the Internet."

  15. Katharine Hayhoe on Climate and our Choices

    Dr. Hayhoe will also be interviewed highly publicly in September during the Texas Tribune "Tribfest", Sat., Sept. 24, 3 pm. Unfortunately, they named the session The Gospel of Climate, playing straight into the "climate change science is a religion" crowd ... no doubt a provocative title. On top of that, Dr. Hayhoe will be one of only two scientists/intellectuals (Dr. Webber from UT the other) in the whole field of speakers in the Energy and Environment sessions ... good luck!

  16. State of the Climate 2015: global warming and El Niño sent records tumbling

    Jonbo @ 4.

    Good article in your link. The PDO is swinging positive to a warming phase, and the AMO could be swinging to a cooling phase, all over the next decade or so. Remember neither of these drives global warming from greenhouse gases, and can only influence that trend to some extent.

    However the Pacific ocean is larger, so would be the dominant force globally and is entering a warming phase. We are heading for warming globally as a whole, but some north atlantic coastal areas could maybe cool or warm more slowly, or have associated dry periods.

  17. Naïve empiricism and what theory suggests about errors in observed global warming

    Also at my blog the main discussion was about the sources for the Einstein quotes. It does not matter much for the story, but I will be more careful next time.

  18. 2016 SkS Weekly News Roundup #34

    Reposting here Mary Ellen Harte's semi-weekly compilation of Climate Change and Green-Energy links in Huffington Post for interested parties.

  19. Naïve empiricism and what theory suggests about errors in observed global warming

    I have always been a bit suspicious of the quote, "No amount of experimentation can ever prove me right; a single experiment can prove me wrong" often attributed to Einstein.  That quote espouses a naive falsificationism which is inconsistent with the subtle thought of Einstein on the philosophy of science.  It turns out the quote appears in none of Einstein's writtings, and though attributed to Einstein by several sources in print, none of those attributions specify at time, place or person to whom it was said.  Therefore, the quote must be considered dubious at best.

    Einstein has written similar things.  In "Induction and Deduction in Physics" he wrote:

    "A theory can thus be recognized as erroneous if there is a logical error in its deductions, or as inadequate if a fact is not in agreement with its consequences. But the truth of a theory can never be proven. For one never knows that even in the future no experience will be encountered which contradicts its consequences; and still other systems of thought are always conceivable which are capable of joining together the same given facts."

    And in an unpublished note he wrote:

    "The scientific theorist is not to be envied. For Nature, or more precisely experiment, is an inexorable and not very friendly judge of his work. It never says "Yes" to a theory. In the most favorable cases it says "Maybe," and in the great majority of cases simply "No." If an experiment agrees with a theory it means for the latter "Maybe," and if it does not agree it means "No." Probably every theory will someday experience its "No"—most theories, soon after conception."

     

  20. gorm raabo larsen at 07:03 AM on 25 August 2016
    Katharine Hayhoe on Climate and our Choices

    Thanks - Brief and Excellent !

  21. There's no correlation between CO2 and temperature

    MA Rodger & Tom Curtis:

    Because Victor cannot abide by the SkS Comments Policy, he has relinquished his privilege of posting comments on this site. Therefore, please do no post any new responses to him.

    Thank you.

  22. victorag@verizon.net at 06:42 AM on 25 August 2016
    There's no correlation between CO2 and temperature

    #121 MARodger:

    What Lovejoy's Figure 3a represents to me is how easily data can be distorted to support just about any theory, providing one is clever enough to adroitly juggle the statistics. And of course Lovejoy is not alone. I see this sort of distortion everywhere in the cli. sci. literature.

    For some examples see the following list

    It wouldn't be so bad if the various attempts reinforced one another or were even consistent with one another, but in most cases they are not. Extraordinary claims require extraordinary evidence. It's not enough to pull a few rabbits out of a hat. The evidence must be there, it must be clear and it must be objective. While highly complex and even convoluted technical discussions are appropriate in a purely scientific paper, it should be possible to boil all that down into a clear and simple explanation that any educated person can understand. And no, simply reiterating over and over that "climate change is real" won't do. 

    Moderator Response:

    [JH] Sloganeering snipped.

    [DB] This participant has recused themselves from further participation in this venue, finding the burden of complying with this venue's Comments Policy too onerous.

  23. victorag@verizon.net at 06:17 AM on 25 August 2016
    IPCC admits global warming has paused

    #10 Tom Curtis: "Further, your argument against the temperature effect of CO2 is entirely statistical."

    I never said I rejected statistics. My point, in agreement with Fyfe's point, is that it is not always the best tool in all circumstances and can sometimes distort the physical reality behind the raw data. 

  24. State of the Climate 2015: global warming and El Niño sent records tumbling

    Thanks for the replies. I read the post article, which looks like we will experience warming from the PDO but then I read that we are entering a cooling period in the AMO. https://theconversation.com/the-atlantic-is-entering-a-cool-phase-that-will-change-the-worlds-weather-42497. Whether these two effects will balance each other out regarding overall surface tempeature, I haven't a clue.

  25. Water vapor is the most powerful greenhouse gas

    Old Sage: Your most recent comment was deleted itn its entirety because it violated a number of prohibitions set forth in the SkS Comments Policy

    You are now on the cusp of relinquishing your privilege of posting comments on this site.

    Moderator Response:

    [PS] Old sage needs to answer the question above. He instead asks questions readily answered in a text book and by people here (see Postive feedback = runaway greenhouse) but seems utterly incapable of understanding the answer. Answering how he understands the temperature of a surface to be determined is best way to sort out misunderstanding/misapplications of physics.

  26. victorag@verizon.net at 01:39 AM on 25 August 2016
    There's no correlation between CO2 and temperature

    #130 MARodger. Thanks very much for going to all this trouble, MA. I won't respond in detail for the usual reason, so all I'll say at this point is:

    I see what Wolfe sees.

    Moderator Response:

    [JH] The discussion of scatter plots has now run its course. It's time to move on to other topics.

  27. Climate-related disasters raise conflict risk, study says

    Haze,

    What you are refering to is called CO2 fertilization, a stabilizing feedback. This stabilizing feedback, all else equal, should be large enough to counter emissions, given a healthy environment. But the environment is not healthy, and this stabilizing feedback is far too small to counteract fossil fuel emissions. Second factor often neglected is that leaves are not all created equal. While C4 plants (mostly grasses) represent only 3 % of species, they represent a disproportionately large % by more than an order of magnitude of photosynthesis due to higher efficiency. They also do better at lower atmospheric CO2 levels. Those same grasses while temporarily fixing more CO2 also have a mature phase with highly increased albedo. (amber waves of grain?) And the 4th factor is instead of producing a woody trunk, c4 grasses put 30% or more of those increased products of photosynthesis directly into the soil in what is called the "liquid carbon pathway". Not only is a higher rate of carbon fixed, but a much higher % is directed into the stable carbon pool as opposed to the labile carbon pool. This "greening" is actually part of a transition to lower efficiency plant species in some areas and part of the long slow process of desertification in some areas as well. (less soil carbon holds less water in the soil to hold plants over through a drought)

    So while you can claim that "seems to fly in the face" if you wish, but digging deeper into the highly nuanced interactions actually brings a different result.

  28. Climate-related disasters raise conflict risk, study says

    Speaking of envronmental degredataion, check out the recently created website:

    Sixteen years of change in the global human footprint 

    The human footprint map measures the cumulative impact of direct pressures on nature from human activities. It includes eight inputs:

    • the extent of built environments,
    • crop land,
    • pasture land,
    • human population density,
    • night-time lights,
    • railways,
    • roads, and
    • navigable waterways.
  29. These are the best arguments from the 3% of climate scientist 'skeptics.' Really.

    eljoris @13, any "current flow" in space is in the form of the passage of positive (typically protons or ionized helium nuclei) or negative particles (typically electrons).  As such, in the vicinity of the Earth, such currents are experienced as components of the solar wind, or galactic cosmic rays; and the energy of the "electrical current" is just part of the energy contributed by those sources.  Both have been quantified, with cosmic rays contributing approximately 0.0000032 W/m^2, and the solar wind contributing a relatively "massive" 0.00035 W/m^2.  These figures include the energy from the particles physical impact, along with that from any current they carry.  For comparison, the total anthropogenic forcing increased by about 1.8 W/m^2 from 1880 to 2010, ie, approximately 560,000 times the energy recieved from cosmic rays, and 5000 times the energy received from the solar wind.  Because these energy sources are so small relative to the normal forings (changes in solar output, volcanism, anthropogenic forcings) they are neglected by climate scientists.

    Cosmic rays may have a secondary effect in which they influence cloud albedo and cloud greenhouse effect.  Current evidence suggest that any such effect is small, but potentially much larger than any direct energy effect.  Climate scientists certainly pay attention to this possibility. 

  30. Naïve empiricism and what theory suggests about errors in observed global warming

    When theory and observations do not match, the theory can be wrong, the observations can be wrong and the comparison can be wrong. What is called observations is nearly always something that was computed from observations and also that computation can be imperfect. Only when we understand the reason, can we say what it was. 

    This is a really good comment and one the deniers don't get. All their hot air about the pause/hiatus and the "excuses" examining the internal variables that could result in such periods is a good example.

    Tx

    All the best.

  31. These are the best arguments from the 3% of climate scientist 'skeptics.' Really.

    As a layman, and non native English speaker, I have a question for the well read to which I haven't yet found an answer on this site: The Earth with its magnetic field is a giant electric dynamo floating in the open electric environment of the solar system which is not separated from the electrical environment of the galaxy. Furthermore, the vacuum of space is a plasma filled environment with loose electrons and electric potentials do generate current flows over intergalactic distances. (This is not even controversial.)

    The physical parts of the Dynamo heat up depending on the intensity of this flux, and science does already know that voltage potentials in the sun-earth space vary with time. Wouldn't it be scientifically prudent to atleast send probes out to verify how this variable changes over time at various points in the solar system and outside of the solar system in our small branch of the galaxy? 

    Compared to this large potential for external forcing (pun intended), and various interacting cycles -which might depend on the relative position and movement of our earth within and through this field of electric potentials-, CO2 and for that matter all other earth based variables might just be overqualified and overweighted. 

    Is this potential mechanism actively being researched? I would like to know how climate science has refutiated that hypothesis because it just 'feels' like something you would need a well researched answer to, taking into account various cycles. Do they even keep an open mind to that possibility or just turn a blind eye to it? 

    Kind regards.

  32. There's no correlation between CO2 and temperature

    Concerning the bogus nature of the Danley Wolfe graphic introduced into this discussion by Victor Gauer (but on the wrong thread).

    May I introduce my own graphic of three panels that illustrates the bogus nature of Wolfe's analysis, my graphic linked here (usualy 2 clicks to 'download your attachment')

    The top panel reproduces Wolfe's data plot, LOTI (I actually use LOTI as published in May 2014 - what should have been the Wolfe data - it is very close to Wolfe's data and indestinguishable for the data most recent to May 2014) plotted against MLO CO2. Note Wolfe repeatedly says he uses GISTEMP Met Station data but he is obviously wrong. He uses LOTI but adds 14ºC to the values. He calls this "absolute" rather than an anomaly although it is simply the anomaly shifted by 14ºC so not the monthly "absolute" values.

    Added to the Wolfe data is the LOTI data for June 2014-to-date as published today. The annual CO2 cycle (unlike the annual LOTI cycle) remains as per Wolfe's plot. Its inclusion has no physical justification, just as retaining the annual LOTI cycle would have no physical justifictaion. Its inclusion is patently wrong.

    The central panel plots the same data but adds a trace using 12-month averages for MLO CO2 and a red trace that additionally uses the 12-month averages for temperature. As the rate of increase in CO2 has been rising over the decades, the red trace is effectively the LOTI time series but with the early years squished up and the later years stretched out. The ratio of most-squished:most-stretched is about 1:3. So conpared with the more normal time series plot of LOTI, this CO2-series plot will markedly eccentuate any slowdown in the LOTI record during the later years.

    The third panel introduces the trend lines drawn on by Wolfe (the black trace). The flat part of the trend for the later years is not calculated as Wolfe describes. Wolfe's "1998-2014" result can be reproduced (down to the "158 observations") using May 2014 published data and the period 4/2001-5/2014. The other flat trend for the earlier years is undescribed by Wolfe. Importantly, the sloping trend Wolfe shows joining the flat eary section to the flat later section cannot be the result of any analysis. It is probably drawn fancifully simply to connect the top and bottom flat trends. It is entirely bogus.

    The yellow trend is the OLS trend for Wolfe's data through the middle part of the data with the narrower yellow lines extending that trend to the ends of the data. The OLS trend for the entirety of Wolfe's data is represented by the white plot and is very little different from the full-length yellow trend plot. It is thus evidently bogus to attempt to argue that there are any periods either at the start or at the end of this data with significantly lower trends. Yet Wolfe does just that!!!

  33. victorag@verizon.net at 14:19 PM on 24 August 2016
    There's no correlation between CO2 and temperature

    #127 P.S.

    Tom, if you go to the SkSc trend calculator, setting the start date to 1960, the end date to 2016, and the moving average to 0 — and select HadCrut4, you'll see a more up-to-date representation that's even closer to your scattergram.

  34. victorag@verizon.net at 13:52 PM on 24 August 2016
    There's no correlation between CO2 and temperature

    Tom's scatterplot

    Global warming 1960-2009

    (from this site www.walkersands.com/Blog/climate-change-in-the-age-of-google/)

    #127  So, Tom, what you are saying is that the congruence I see between these two graphs is a meaningless optical illusion?

    One other thing. Your correltion of 0.857 covers the entire scattergram, which was not the point. The claim is that three different scattergrams are represented, the first showing little to no correlation, the middle showing significant correlation and the last also showing no significant correlation. That's what I see in both Wolfe's graph and yours. And if there's a problem assigning a statistically derived value to each of these because they're too short, then as I see that's a problem with the statistical methodology, not with our ability to evaluate the data per se.

  35. Climate-related disasters raise conflict risk, study says

    Haze @5 . More greening [leaf area] in recent decades is evident from the satellite images. This is good for herbivores and livestock. However, higher average temperatures, storms, and heat-waves have a deleterious effect on maize, rice and wheat crops (but especially the maize). Overall crop yields decline . . . and greater extension of croplands is needed.

    Arguably, that produces an environmental degradation - it depends on what definition is used !

  36. Climate-related disasters raise conflict risk, study says

    RedBaron@4.  Your comment  "Why would AGW, whose major component is environmental degradation, be any different?"  seems to fly in the face of the many reports noting the increased greening and decreased browning of the planet due to the effects of CO2.  

    For example, Zhu et al note from satellite measurements of leaf area index (LAI)  "a persistent and widespread increase of growing season integrated LAI (greening) over 25% to 50% of the global vegetated area, whereas less than 4% of the globe shows decreasing LAI (browning). Factorial simulations with multiple global ecosystem models suggest that CO2 fertilization effects explain 70% of the observed greening trend, followed by nitrogen deposition (9%), climate change (8%) and land cover change (LCC) (4%).  

  37. 2016 SkS Weekly Digest #34

    At a recent auction of electricity in Chile, an un-subsidized solar farm was the lowest bidder with a bid of 2.72 cents per kilowatt hour.  Joe Romm discusses the auction here.  People who say renewable energy is too expensive will have to explain why coal was almost twice as expensive in this auction.  The Atacama desert has a very high sun resource but they need more long distance transmission lines to bring the power to their cities.   

    Hopefully solar will continue to decrease in price so that buisinesses install solar to save money.  Already, according to Forbes, ""Wal-Mart [is] the single biggest commercial solar generator in the country (United States)."  (in November 2015 they had about 105 megawatts of solar installed.  They save money by installing solar arrays on their roofs.  Other commercial real estate owners are starting to install solar, it is cheaper than the grid.

  38. There's no correlation between CO2 and temperature

    victorag @126, for any scatter plot where the data has a correlation less than 1, and conforms approximately to a linear trend, if you take a small section of the total data measured by distance along the x-axis, the subsection of the data will look like it has a much smaller correlation.  That only indicates that by using a small section of the data you are maximizing the noise to signal ratio.  Because the temperature noise is autocorrelated, the small subsection may give the appearance of a very different trend, but again that is just a product of cherry picking.

    If you want to find a genuine divergence from the scatter plot, you need to find a significant body of data that lies more than two standard deviations from the trend line.  In this case, that means +/- 0.3 C relative to the line 0.0094X - 3.05.  For the demarcated x values, this gives parameters of:

    X value Mean -2 SD +2 SD
    300 -0.23 -0.52 0.06
    320 -0.05 -0.34 0.24
    340 0.14 -0.15 0.43
    360 0.33 0.04 0.62
    380 0.52 0.23 0.81
    400 0.71 0.42 1
    420 0.89 0.6 1.18

    A quick check shows that there are no major clusters of points lying outside the +/- 2 SD limits, and hence no reason to assume a break point in the trend.

    We can take this further by extending the data using that from Law Dome.  Unfortunately when we do so we are limited to annual values generated by a 20 year spline smooth for CO2, and hence annual values for temperature.  That artificially inflates correlation, but not by much given the small variance of CO2 to begin with.  It has no effect on trends.  So, having done so we find the trend is 0.0097 X - 3.13.  The values are within two standard errors of the predicted trend and intercept based on the Mauna Loa data, and are minimally divergent in absolute values.  That indicates the observed trend in the Mauna Loa/Temp scatter plot is robust, and has been in effect since 1850 at least.  Given that, looking to subdivide the Mauna Loa data is clearly not justified (and not justified on two distinct tests).

    There are reasons for a slight visual distinctiveness in the two regions you point out.  Specifically, both the rate of increase in CO2 concentration and in temperature have tended to increase over time.  This results in the points being more densely scattered on the left of the graph than on the right.  This is even more apparent on the Law Dome scatter plot.  As it happens there was an acceleration in the increase in CO2 concentration about when CO2 concentration reached 340 ppmv, which accounts for the denser plot below that level.  Near 400 ppmv the distinctive appearance results from the reduced linear least squared error fit for temperature (ie, not the underlying trend, but the superficial trend) followed by the spike in temperatures starting around 2013.  That reduced superficial trend, however, does not carry the temperature values outside 2 standard deviations of the y estimate, however, and therefore is irrelevant unless it were to continue and carry the values outside that range.  Of course, with the recent spike in temperatures it has patently not done so.

  39. victorag@verizon.net at 05:58 AM on 24 August 2016
    IPCC admits global warming has paused

    #9 Tom Curtis

    I responded to your last post, with the new scattergram, on the other thread. To my eyes your result isn't that different from Wolfe's.

  40. victorag@verizon.net at 05:56 AM on 24 August 2016
    There's no correlation between CO2 and temperature

    #125 Thanks so much, Tom, for the very thorough explanation, and the corrected scatterplot. Maybe my eyeballs are deceiving me, but I see more or less the same picture as in Wolfe's scatterplot. Random until roughly 340 ppm, correlated until roughly 380, and then random again — with a bit of a spike after 400. What do you see?

  41. IPCC admits global warming has paused

    victorag @6, I quite agree that:

    "Statistical analysis is a vital tool in any climate scientist’s toolbox. However, even the application of sophisticated statistical tools can shed more heat than light, particularly in arguments that focus on limited aspects of statistical significance rather than on broader physical understanding. . ."

    You, however, cannot consistently do so.  First, that is because it means Fyfe et al's acceptance of evidence of a change in forcing leading to a slow down logically precedes their acceptance of the existance of a slow down.  Logically, therefore, it is not an attempt to plug up a theory and make it resistant to contrary observations (as you have elsewhere suggested).  Either the evidence of reduced forcing that justify belief in a slow down is sound (in which case your attempt to impugn it is ill motivated), or it is not (in which case it cannot be relied on to infer the existence of a slowdown, where the statistical evidence is inadequate to justify that inference).

    Further, your argument against the temperature effect of CO2 is entirely statistical.  (Bad, and cherry picked statistics, but statistical never-the-less).  But if you accept the principle above, you cannot rely on entirely statistical arguments in judging the effect of CO2.

    In short, your defence of Fyfe et al based on that quote is, for you, a matter of tactical convenience only as there is no evidence you apply that principle more generally.

  42. victorag@verizon.net at 05:40 AM on 24 August 2016
    IPCC admits global warming has paused

    Here's another study, dating from 2014, thus prior to Fyfe et al., in which the "hiatus" is taken seriously — only in this case the authors are unable to account for it: Application of the Singular Spectrum Analysis Technique to Study the Recent Hiatus on the Global Surface Temperature Record

    Some excerpts:

    From the abstract:

    Global surface temperature has been increasing since the beginning of the 20th century but with a highly variable warming rate, and the alternation of rapid warming periods with ‘hiatus’ decades is a constant throughout the series. . . 

    Henceforth, MDV [multidecadal variability] seems to be the main cause of the different hiatus periods shown by the global surface temperature records. However, and contrary to the two previous events, during the current hiatus period, the ST [secular trend] shows a strong fluctuation on the warming rate, with a large acceleration (0.0085°C year−1 to 0.017°C year−1) during 1992–2001 and a sharp deceleration (0.017°C year−1 to 0.003°C year−1) from 2002 onwards. This is the first time in the observational record that the ST shows such variability, so determining the causes and consequences of this change of behavior needs to be addressed by the scientific community.

    From the Discussion section:

    After the maximum warming rate associated with MDV was reached by approximately 1990, ST showed a distinct peak from 1992–2001, with an unprecedented increase of its warming rate from 0.0085°C year−1 to 0.017°C year−1, almost doubling in one decade. After this warming rate peak, the ST shows a pronounced decline, 0.017°C year−1 in 2001 to 0.003°C year−1, in 2013. This type of quick fluctuations in the ST warming rate has no precedent in the observational record (Fig. 3a). . . 

    Therefore, the very recent strong changes observed in the warming rate associated with the ST appear to be a global phenomenon that had not occurred before (at least not during the last 160 years). It could not be attributable to MDV or any other form of climatic variability (such as solar cycles), as the different contributions are effectively separated by the SSA analysis (Fig. 2). This unprecedented modification of the ST behavior should be more deeply studied by the scientific community in order to address whether a change in the global climate sensitivity [21] has recently occurred.

    Here's an article on these findings from the European Commission's website: Last decade's slow-down in global warming enhanced by an unusual climate anomaly

  43. IPCC admits global warming has paused

    victorag @8, I have responded to your comments on CO2 correlation on the original (and appropriate) thread.  In the comment I have shown that:

    Using the data as downloaded (Mauna Loa monthly plus BEST LOTI) increases the correlation fractionally.

    And that Wolfe cherry picks a restricted temperature data set which artificially deflates the correlation

    I have also shown a new scatter plot satisfying your stricture that the data as downloaded be used (except for interpolation of missing months).

     

    MA Rodger, regardless of Briggs merits or otherwise, correlation is covariance divided by the product of the standard deviations of the data.  Smoothing reduces the standard deviation, and therefore must increase the correlation.  This was something I was quite aware of which was why my primary analysis used monthly data to obviate any issue of inflating the correlation by smoothing.  As I went out of my way to avoid artificially inflating the correlations, I take exception to Victor's suggestions that my mathematics has been manipulation rather than analysis.

  44. There's no correlation between CO2 and temperature

    victorag has mistakenly posted a response to my post @119 on the incorrect thread.  As the comments are off topic on the other thread, I will reply here.

    Victor wrote:

    "Regarding the difference between "eyeballing" and statistical analysis: there are many ways to manipulate results using statistics, whereas one's eye sees the data directly. Sorry, but where the picture is clearly there for all to see, I'll trust my eye, thank you."

    First, and most obviously, it is as easy to distort with graphs as it is with statistics.  Indeed, in some respects easier.  Second, I find the imputation that my statistical analysis, which I fully described, were designed to manipulate the data, still less to "modfied [the data] to produce the desired result".  For the full Mauna Loa comparison I used the same Mauna Loa data that was used by Danley Wolf, with the sole exception that I used anomaly data because the temperature data was anomaly data, and I wanted to compare like to like, and that I interpolated missing values.  I deliberately used monthly data to avoid artificially smoothing the data.  Over the full interval of Mauna Loa data, had I instead used the raw montly values (with interpolation for missing months), ie, used the data essentially as downloaded, it would have increased the calculated correlation from 0.855 to 0.857, a negligible difference.  That clearly demonstrates that my high calculated correlation was not an artifact of using anomaly data for CO2 concentration.  It should be noted that Mauna Loa, because of its location in the northern hemisphere, experiences a larger seasonal cycle in CO2 concentration than does the global average, so that using the raw data with no seasonal cycle adjustment itself represents an artificial deflation of the correlation.

    "Smoothing creates artificially high correlations between any two smoothed series."

    This is an obvious consequence from the formula for correlation, which is the covarriance divided by the product of the standard deviations.  Smoothing reduces the size of the standard deviation and thereby increases the correlation.  But, just as it is possible to artificially inflate correlations by reducing the standard deviations of the data, so it is possible to artificially deflate increasing the standard deviation (of which more later).

    "Regarding scattergrams: the scattergram offered by Tom lacks sufficient detail to be very useful. Here's another that does, compiled by Danley Wolfe from raw data available to all at:

    Mauna Loa: ftp://aftp.cmdl.noaa.gov/products/trends/co2/co2_mm_mlo.txt

    NASA GISS: http://data.giss.nasa.gov/gistemp/tabledata_v3/GLB.Ts.txt

    Wolfe does nothing to "massage" his data, it's directly transcribed from the two sites referenced above."

    First, Wolfe did not "directly transcribe" the data.  Specifically, with regard to temperature he added the mean annual temperature durring the baseline period to all values in the mistaken belief that he would thereby convert them from anomaly values.  Anomaly values are calcultated from monthly means, however, so Wolfe's hybrid data represents neither anomaly values or the actual temperatures experienced.

    Second, Wolfe cherry picks his data set.  Instead of using the GISS Land Ocean Temperature Index, he used the GISS Land (Meteorological Stations only) data.  Because that data represents only a third of the globe, and because it largely excludes oceans, the data is far more variable than the GISS LOTI.  Thus by cherry picking the meteorological station data, he takes advantage of the fact that inflating the standard deviation of the data artificially deflates correlations (alluded to above).  This by itself deflates the correlation by about 20%, and the R-squared by about 36%.

    He gains further advantages from his cherry pick.  First, because of the limited geographical area covered by his data, temperature variability is more influenced by local factors, and less influenced by global factors - further decreasing the correlation with CO2.  Second, the meteorological station data is distinctly flater after 1998 than is the Land/Ocean data, thereby further deflating the correlation in the so called hiatus period.  Wolfe is doing well, in that he got three distortions of the data from just one cherry pick.

    In any event, here is a scatterplot of the monthly Mauna Loa data as downloaded except for the interpolation of missing values, against the BEST LOTI.  The correlation as previously noted is 0.857 (R^2: 0.734):

  45. victorag@verizon.net at 04:23 AM on 24 August 2016
    IPCC admits global warming has paused

    #7 MA Rodger

    If Wolfe's scattergram doesn't suit you, why not produce one that does? But if you do, please use raw data, not data that's been statistically modfied to produce the desired result. 

  46. IPCC admits global warming has paused

    Victor Gauer @6.

    I was wondering how long you would take to introduce Danley Wolfe's fabrication into SkS. His MLO CO2 data is as stated but is unadjusted for the annual cycle. And the GISTEMP data isn't as Wolfe states. It is not "NASA GISS global mean (absolute) land temperatures" as Wolfe claims. It is the NASA GISS LOTI anomaly with 14ºC added. (In detail, its origins appear to be a 'collection' of LOTI data. It is certainly not the LOTI data as published in May 2014.) The steep slopey line Wolfe draws on to his graph has no basis other than arbitrarily joining up the two flat unslopey lines, which are themselves not the cherry-picked OLS results that Wolfe claims. When I have a moment I shall illustrate graphically how dreadful this nonsense from Mr Danley Wolfe truly is.

    And after a quick google, Dr William M Briggs appears not to be a good expert to rely on uncritically. Specifically here, what does he mean by "smoothed"? Is it a concern for anything under discussion here?

  47. victorag@verizon.net at 02:35 AM on 24 August 2016
    IPCC admits global warming has paused

    #2 Tom Curtis. I'm not qualfied to distinguish between the claims of Werner and Fyfe, but I do find myself agreeing with Fyfe when he comments on the value of a purely statistical analysis:

    Statistical analysis is a vital tool in any climate scientist’s toolbox. However, even the application of sophisticated statistical tools can shed more heat than light, particularly in arguments that focus on limited aspects of statistical significance rather than on broader physical understanding. . . 

    These results illustrate the dangers of relying solely on a statistical test to tell us whether there is, or is not a physically-based change in warming rates.

    Regardless of which view is the correct one, such disputes shed light on the problems faced by climate scientists intent on proving their thesis beyond reasonable doubt. It's all too easy to fall back on the notion that it's now up to skeptics to provide the evidence they themselves have been unable to provide.

  48. victorag@verizon.net at 02:10 AM on 24 August 2016
    IPCC admits global warming has paused

    (My apologies again: the links I provided got lost when I re-pasted this post. Please delete post #4. Thank you.)

    For reasons already stated, I will be brief, so as not to waste my time with long explanations that might get edited or deleted. Maybe it's better that way anyhow.

    Regarding the difference between "eyeballing" and statistical analysis: there are many ways to manipulate results using statistics, whereas one's eye sees the data directly. Sorry, but where the picture is clearly there for all to see, I'll trust my eye, thank you.

    Regarding statistical smoothing:

    Smoothing creates artificially high correlations between any two smoothed series. Take two randomly generated sets of numbers, pretend they are time series, and then calculate the correlation between the two. Should be close to 0 because, obviously, there is no relation between the two sets. After all, we made them up.

    But start smoothing those series and then calculate the correlation between the two smoothed series. You will always find that the correlation between the two smoothed series is larger than between the non-smoothed series. Further, the more smoothing, the higher the correlation. (From the blog of Dr. William M. Briggs (PhD in Mathematical Statistics))

    Tom Curtis at #119: Regarding scattergrams: the scattergram offered by Tom lacks sufficient detail to be very useful. Here's another that does, compiled by Danley Wolfe from raw data available to all at:

    Mauna Loa: ftp://aftp.cmdl.noaa.gov/products/trends/co2/co2_mm_mlo.txt

    NASA GISS: http://data.giss.nasa.gov/gistemp/tabledata_v3/GLB.Ts.txt

    Wolfe does nothing to "massage" his data, it's directly transcribed from the two sites referenced above.

     

  49. There's no correlation between CO2 and temperature

    MA Rodger @123, given how wrong Victor is regarding CO2 concentration/Temp correlation, I think you are being over generous in your interpretation, unless, and until Victor corrects the record.

  50. There's no correlation between CO2 and temperature

    Tom Curtis @122,

    You are entirely correct except that Victor has been so frequently using the phrase "CO2 emissions" down this thread in place of 'increased atmospheric CO2 levels' or 'anthropogenic CO2 forcing' or whatever, that I ignore the true meaning of it and substitute the sensible intended meaning.

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