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Comments 66151 to 66200:

66151. Tom Dayton at 10:20 AM on 23 January 2012
       The National Center for Science Education defends climate science in high schools
       Another organization that tries to educate about climate change is the U.S 's National Earth Sciences Teachers Association. Their executive director Dr. Roberta Johnson yesterday was on NPR radio's This American Life in episode 424, Kid Politics, Act Two. Host Ira Glass had her in one studio and a young teenager in another studio. He had the Dr. give her best arguments and the teenager respond with how convincing it was. The teen was thoroughly unconvinced. The teen's bottom line was that she might be convinced if she saw both sides of the argument laid out side by side. Hey! That's what Skeptical Science does! Will somebody please tweet or comment on Facebook to that radio program? I don't tweet and I rarely Facebook. Also it would be good for somebody to ensure the Dr. knows that SkS provides what the teen was asking for.
66152. skywatcher at 10:18 AM on 23 January 2012
       A Comprehensive Review of the Causes of Global Warming
       patonomics, it seems you asked something quite unreasonable in reality. Reality is a lot more complex than a physical model of reality (google "spherical chicken" or "spherical cow"), yet some consequences of complex interactions are adequately modelled by simplifications, and other consequences are not dependant on the details of the complexity. You cannot write an equation for the totality of a volcanic eruption, with magma, tephra fall, gas released, pyroclastic flows, landslides, lahars, earthquakes and the rest. But you would not expect a single equation for such a complex process, yet it would be utterly naive to suggest we have no idea of how volcanoes work, or their environmental and even climatic impacts. Not all science works by deriving individual equations or laws. Why not look at the following thread: Ten indicators of a human fingerprint on climate and see if you can find a reason why these indicators are not valid. See if you can find fundamental reasons why Richard Alley's AGU presentation on CO2 as the key 'control knob' on climate is fundamentally flawed. The physics of human-caused global warming and more broadly of the greenhouse effect is not a theory on its own, but a consequence of the theories governing atmospheric physics, and absorption/emission of radiation by materials at specific wavelengths See Spencer Weart's excellent history of the CO2 greenhouse effect. Without these theories, most of astronomy and astrophysics, dependant on understanding stellar chemistry based on the absorption and emission of radiation by gases at specific wavelengths would not work. Heat-seeking missiles would miss - their development is inextricably tied to our understanding of the greenhouse effect). A myriad of other modern technologies do not work if you disregard the principles behind the greenhouse effect. But not everything that "works" has a single meaningful equation that describes its operation. The challenge for those doubting the validity of climate science is to find a way that the overarching physics works, yet somehow does not apply to our atmosphere, where it has been observed to work.
66153. patonomics at 09:40 AM on 23 January 2012
       A Comprehensive Review of the Causes of Global Warming
       I must humbly acknowledge all responses and offer personal respect to each individual (in favor and against my views as critics) individually for your kindness so far. I think I am blessed. Here I will record some of clarification which will give clarity about my views further. To respond respected Moderator’s Response at #29 : I 100% agree with you “Grain silos are not good models of the Earth's climate system.” And I never claimed that, if you read between the lines in #29. The central point to mention there was “Grain silos are simplistic and manageable and completely observable and verifiable case if one compare with climate science. And even with today’s critical skills in modeling and with super computers, still it create lots of error. Climate science is with multitude of variables and much more complex. So when simple case (Grail silos) is NOT accurate what to expect predictions accuracies in complicated science of Climate”. To respond #30 @Tom Curtis: The case I have referred is part of scientific analysis with temperature in Centigrade, and I have NOT discussed this as Scientific Jugglery, so please please give attention about what they (researchers) said and done and measured temperature in Centigrade only NOT in Kelvin, also “in that particular case” science of seed/grain has no need to be referred with base of Temperature Kelvin 0, so please stop distorting the facts. I know most of the participants in this forum are serious and they do understand you are trying to distort the facts. To respond #31 @muoncounter: I definitely agree with you is lot of laws to explain something in physics. My submission is: if someone in this earth, claims human generated CO2 as deterministic reason (or most likely, and cannot be unlikely) for surface temperature rise of earth, it should be quantitatively deterministic. “So the claim such claim” temperature can be expected (if it’s NOT too much expectation form a lifelong student of science) to ask for deterministically defined in an equation along with many other variables which have positive and/or negative impact on surface temperature variations in this earth. To respond #32 @Glenn Tambly: in the following general equation f (X1, X2, X3, . . . . . Xn) is neither simplistic nor complicated, its general equation, and capable to be actually derived as simple or as complicated once wants to make it. So the general equation is left to one who wants to make it deterministic with respect to all integrated knowledge of co2 generation from all known sources, from land, sea, other water bodies, all animals (including amebas to humans), and all plants, and ALL other variables in climate that one claims to vary the temperature T(temp at time t) = f (X1, X2, X3, . . . . . Xn)* + c, * Where X1, X2, . . . . , Xn are variables, and they may very well be multidimensional To Respond #34 @Philippe Chantreau: I respect you as a person that you are doing your best to respond. I need to clarify I have no connection with “University of Waikato” what so ever, I just googled for and I get references and just refer it to make my point. Here I have again googled for World’s top university in Physics and now will be using some reference from University of Cambridge (that claims to be number 1 University in Physics)” which may not be offensive to you (I can just hope with a positive mind). I respect your views and you any way, and still we both can agree to disagree with our own individual perceptions. I hereby submit to you, please see the following, if you will like to agree or disagree with information, I agree with. (-snip Philosophy of Science What Is Science? Hasok Chang, Anna Alexandrova (8 lectures, Michaelmas Term) What makes science better than, or at least different from, other systems of human thought? Is there such a thing as the scientific method? Is the development of science a linear, orderly and cumulative process, or an unpredictable sequence of changes? Karl Popper rejected empirical proof as the ideal of scientific knowledge, arguing that a genuine attempt to falsify one's own theories was the hallmark of the critical attitude essential to science. In contrast, Thomas Kuhn regarded a dogmatic adherence to a paradigm as the hallmark of 'normal' science. Imre Lakatos attempted to reconcile these views, to show how critical progress was compatible with a degree of dogmatism, according to his 'methodology of scientific research programmes'. Paul Feyerabend saw such attempts as futile, arguing that science progressed best when it was not constrained by any rigid notions about method. After reviewing these conflicting views on the nature of science and its method, we will finish with some careful reflections on whether science can reliably attain the truth about nature. Introductory reading: Alan F. Chalmers, What Is This Thing Called Science?, 2nd or 3rd edition (I have just read the book in 2011, and find really eye opening for me, and I think I should had read this book much much earlier probably in my primary school days as I had started with curiosity in science) Theory and Evidence Hasok Chang (4 lectures, Michaelmas Term) Whatever one might think of the scientific method, it would be difficult to deny that we do give more credence to a theory as it accumulates more positive evidence. But there are many complex questions. Measuring the degree of confirmation is not a trivial matter. Some classic paradoxes show that what we mean by 'positive evidence' at all can be highly ambiguous. The theory-ladenness of observation creates a threat of circularity in the confirmation relation. The presence of auxiliary assumptions blunt the force of any confirmation or refutation that an observation may have on a theory. And what kind of theory can we confirm by evidence, in any case? Is it a law of nature embodying causality or necessity? Or is it merely an empirical regularity? Or a model that is not meant to be literally and completely true of the world? Introductory reading: Alan Musgrave, Science, Common Sense and Scepticism Hidden obnoxious comment here-) To respond #35 @ Rob Painting: refer my response to #34 that I have no relation or connection to “University of Waikato”, I have just googled to find references from a University, to make my point. And I do respect you and your views, even when I have possess an individual mind, to agree or disagree with some science. I claim that I do not have “A sheep's herd mentality” – I own a mind of my own, and can validate facts when logically presented and stand alone with my own judgments or change my judgment, even when whole world is against me. So please keep your personal attack mentality for responding to someone. You can neither heart me nor make me happy.
       Response:

       [DB] Long off-topic segments snipped.

66154. skywatcher at 09:24 AM on 23 January 2012
       Climate Change Denial and the Media - Banishment of Science Reality
       skeptikal #25, you'll find people here are entirely welcoming to enquiring minds, but tend to react sensitiviely to those parroting tired old myths such as the claim that we only think it's happening because of models. In reality our understanding is based on a wealth of direct empirical evidence of a human fingerprint on the global warming signal - note particularly the reduction in heat escaping to space and more heat returning to Earth at GHG-specific wavelengths. This evidence is right in line with over a century of predictions based on the physical properties of CO2, and right in line with a wealth of palaeoclimatic evidence demonstrating that CO2 is the biggest control knob on climate (I'd hugely recommend watching this Richard Alley presentation - the speaker is perhaps the Republican most worth listening to in the world!). As others have said, data adjustment, which you put such a negative spin on, happens necessarily all the time. It is not done arbitrarily, and is always documented and justified. It is crucial to extract meaningful information from indirect sources, be they thermometers, sea floor sediments, or electromagnetic radiation; it is also crucial if you want to bring together multiple data sources, say thermometers at different elevations and so on, if you want a meaningful combined record. Genuine scepticism is a valued trait (every good scientist is fiercely sceptical of both their own work and others, however good the work is), but please provide evidence for your sceptical views on climate. Be sceptical not only of information that is in conflict with your worldview, but also be sceptical of information that agrees with your worldview.
66155. EliRabett at 08:04 AM on 23 January 2012
       The role of stratospheric water vapor in global warming
       The oxidation of methane occurs mostly in the troposphere with a lifetime of ~ 5 years. However, this is not complete, and some leaks into the stratosphere. Methane in the stratosphere is the source of much of the water vapor there, since little can get through the cold trap at the tropopause. It is correct to say that methane oxidation in the stratosphere is the source of the additional water vapor there. It is not correct to say that methane oxidation occurs mostly in the stratosphere
66156. JMurphy at 07:12 AM on 23 January 2012
       How do Climate Models Work?
       Very good, informative and easy-to-understand article. Thanks.
66157. Rob Painting at 06:47 AM on 23 January 2012
       A Comprehensive Review of the Causes of Global Warming
       Earth sciences taught at the University of Waikato is appalling. My youngest son just finished at Waikato (not studying Earth sciences though) and was flabbergasted at the fake-skeptic nonsense Earth sciences students were mouthing. So if Patonomics is going there I fully understand his confusion on climate science. Earth sciences at Otago or Victoria University are of a far higher standard.
66158. John Hartz at 06:43 AM on 23 January 2012
       Climate Change Denial and the Media - Banishment of Science Reality
       The Op-Ed that pbjamm referred to is: “The verdict is in on climate change” by Naomi Oreskes published by the LA Time on January 22, 2012. The sub-title of Oreskes throught provoking article is: “When it comes to climate change, open-mindedness is the wrong approach.”
66159. actually thoughtful at 06:26 AM on 23 January 2012
       2012 SkS Weekly Digest #1
       KR - on the issue of whether sites will hold themselves to the standards they "set" for SkS - I can answer that the site called Wattsupwiththat (WUWT) will - Here is what WUWT says about SkS (the only site WUWT holds out for special treatment): "(unreliable) due to (1) deletion, extension and amending of user comments, and (2) undated post-publication revisions of article contents after significant user commenting." Other than my post at 58 I know nothing about (2). But I can tell you that yesterday, on WUWT moderator amending my comments (by deleting harmless links to SkS) - I say harmless because it didn't involve any controversy, just answering another posters claims with an appeal to the facts (handily categorized here at SkS). I then responded by asking the moderator to allow a debate on the science to occur. Deleting request to allow science on WUWT I don't know what "extension" means -but the moderators did comment (inside my post) - which might be what extension means. So yes, a double standard is now documented. I doubt there is much surprise. I implore SkS to give us a site that is above this type of tit-for-tat - transparency, transparency, transparency! Beyond the borehole type concept KR mentions, I think serious consideration needs to be given to an archive for update/erroneous articles - this could have all kind of labeling that marks it as old/out of circulation/errant/wrong etc. - but transparency means you can see how things looked. And yes - our mistakes will be there for the world to see - even after we fix them. And any serious, credible person will put SkS up another 2 or 3 notches in respect for having the balls to do it. I note that *doing it right* always takes more effort than doing the minimum acceptable. I hereby offer some of my time to help in the *do it right* effort. As always, I sincerely appreciate all the behind the scenes work, and benefit from the end results.
66160. John Mason at 05:56 AM on 23 January 2012
       Arctic methane outgassing on the E Siberian Shelf part 2 - an interview with Dr Natalia Shakhova
       Wili, The goose has been in the oven for sometime already! Hence my parting statement, which I think you will tend to find in most articles on this subject. WRT your question: lots of possibilities to read into this statement still. 50 Gt over what time period? A year? Ten years? Ten hours? Is there enough methane present for it all to come out in one place or, as I suspect, and alluded to in the article, is not a more likely scenario one in which an increase in outgassing via multiple pathways occurs over an extensive area? We don't know. Detection would depend on synoptic patterns at the time, which would control boundary-layer windfields in terms of direction, fetch and speed. An alternative might occur if a 5-15% methane-air mix was generated: enough of that and any ignition-source would provide something more likely to be picked-up on seismographs.... However, one could speculate until the cows come home and such topics are likely better for discussion over a pint or two of beer! Other questions likewise abound: thus I'm looking forward to examining the next data-release and in due course the results from further fieldwork. I am sure we will be returning to this topic again and again in the coming years. But for now, I would caution that is very tempting to jump to conclusions WRT Arctic methane, but in doing so without strong evidence, one is diverging from science, which is something I'd prefer to leave to politicians!
66161. funglestrumpet at 05:43 AM on 23 January 2012
       How do Climate Models Work?
       barry @ 13:08pm (comment numbers all at '1' at time of writing) I would support your point if the articles showed any sign whatsoever of becoming typical of GreenPeace output. However, I see no harm in tub thumping in the comments section, if only because it is likely to be read by persons such as myself, who come here for accurate information on the topic and quite possibly feel as I do that there are overwhelming forces with a vested interest in keeping b.a.u. At least it sure feels that way. I for one will feel it all worthwhile if, say, my suggestion that the opening ceremony of the Olympics by subject to protest by the younger generation who are going to be subject to major effects of climate change, gets taken up by some activist group or other. Heaven knows, can it really be argued that simply proving people like Monckton wrong is a success? Lets face it, he doesn't seem to have changed his script, does he? He even gets introduced to Congress as one of the world's leading climate science experts! Perhaps SKS needs a 'paramilitary' wing! (I joke - with Shakespeare's 'many a true word ...' in mind.)
       Moderator Response: [muoncounter] Further comments on 'tub thumping' are off topic for this thread. Use 'The Big Picture' thread for general comments about advocacy. If you have more specific advocacy issues, find the appropriate thread.
66162. wili at 05:27 AM on 23 January 2012
       Arctic methane outgassing on the E Siberian Shelf part 2 - an interview with Dr Natalia Shakhova
       Thanks for the clarification, John. I get the sense that by the time we have a really good idea of what is going on, our goose will already be pretty well cooked. I wonder if you could clarify something else. If there was a major one-time eruption of methane, of the sort Shakhova discussed (~50 Gt iirc), how long would it take a land-based monitoring station a thousand or so miles away to detect it?
66163. Chris G at 05:15 AM on 23 January 2012
       2011 Hottest La Niña Year on Record, 11th-Hottest Overall
       Re: John (#11) If the ocean retains relatively more energy (heat) during a La Nina relative to an El Nino, I suppose this means we can expect more verbiage about "missing heat" in 2012. It'll be an easy cherry pick to show a lack of temperature increase in the atmosphere while ignoring the temperature increase of the oceans, in the totality that we can measure, rather than just whatever layer happens to fit the preconceptions. Re: Tom (#21) Thanks for that reference. I have had heard, in the past, and had trouble accepting, that the human signal (GHG) only started about 1950. I always figured it was there, just hard to detect. And then there is the bit of, feedbacks aside, a constant increase of GHGs would produce a logarithmic (decreasing slope) curve, but an increasing rate of growth of GHGs should produce an increasing slope curve. If you add them together, does the result have a positive or negative second derivative? Anyway, that reference clears a few things for me.
66164. Tom Curtis at 04:47 AM on 23 January 2012
       Monckton Myth #11: Carbon Pricing Costs vs. Benefits
       Waldo @46, Monckton made a similar effort against Australia's Carbon Tax which was demolished in analysis, but unfortunately I cannot lay my hands on the analysis at present. Looking briefly over his Canadian effort I have already detected one error in which he under estimates the temperature effect by a factor of 14, even granting his numbers for change in CO2 concentration (which I have not checked). If you want good information on the Canadian Scheme, probably this is your best bet. It claims a 1.5 billion dollar net current benefit assuming a 3% discount rate; which compares to Monckton's claim of a net 6.4 Billion dollar cost. Given that the gross cost is estimated at $8.2 Billion, with a benefit of $6.7 Billion dollar Gross benefit excluding the benefits from reduced greenhouse emissions, Monckton's claim is unlikely to stand up to analysis.
66165. Waldo at 03:56 AM on 23 January 2012
       Monckton Myth #11: Carbon Pricing Costs vs. Benefits
       Hello! I have been reading this site for some time and decided to ask the opinion of the commentators here on Monckton's "Regulation Without Reason" http://jonova.s3.amazonaws.com/monckton/canada-coal-2011.pdf I've found that it has one obvious problem in that it purposefully excludes the co-benefits of the regulations being assailed. The math appears fuzzy as well but I'm not a math wiz so I was hoping to get some insight into that portion of it. Thank you!
66166. pbjamm at 03:54 AM on 23 January 2012
       Climate Change Denial and the Media - Banishment of Science Reality
       michael sweet@24 The comments section of that Op-Ed is one of the saddest things I have ever read. There is a desperate need for some actual facts over there, but I doubt that the commenters are interested anything but talking points.
66167. Philippe Chantreau at 03:34 AM on 23 January 2012
       A Comprehensive Review of the Causes of Global Warming
       Patonomics your repeating of the same sentence as if it was a mantra does not flatter others' perceptions of your intrinsic ability to reason on your own. The U. of Waikato's language is overly simplified and erroneously compares level of certainty of concepts that can not be put on the same scale. It is inadequate and misleads the readers into thinking that there is a hierarchy where there isn't one. Thinking critically involves scrutiny of even the sources that teach us to think. Are you always going to recite the same mantra from U.Wai?
66168. Bob Lacatena at 03:18 AM on 23 January 2012
       How do Climate Models Work?
       Kate, I've been a bit overwhelmed with work, so I didn't get to see this post before you put it up, but when you mention that grid cells are often 100 km wide, which seems large, you might also point out that the surface of the earth is 510,072,000 km². A 100 km cube/wedge will have a contact surface area of of 10,000 km². This means (not accounting exactly for the spherical shape of the earth, and how the wedges change in dimensions as one approaches the poles) that you have somewhere around 51,000 cubes in your surface grid alone!!! And then you need to multiply that by the number of levels in your atmospheric representation! So while 100 km may seem "huge" to a small, lonely, self-centered person (or any other sort of person), when one is talking about a global climate model... not so much.
66169. Philippe Chantreau at 03:10 AM on 23 January 2012
       Climate Change Denial and the Media - Banishment of Science Reality
       Skeptikal, the fact that you bought into the myth that scientists were predicting an ice-age in the 70s clearly indicate that you are lacking on the skepticism front. Yet you adorn yourself with that screen name. What did you expect? There is no shortage of ways for you to prove that you are not a fake, if you truly are not one.
66170. les at 02:45 AM on 23 January 2012
       Climate Change Denial and the Media - Banishment of Science Reality
       I think the comment in 26 should be appended to the comments policy or displayed in the user registration page...
66171. Tom Dayton at 02:36 AM on 23 January 2012
       Climate Change Denial and the Media - Banishment of Science Reality
       skeptikal, you will find that the tones and assumptions you make in your comments tend to get reflected in the tones of the responses. Re-read your original comment for its tone and assumptions, then re-read the immediate responses to that comment for their tones. Then re-read your subsequent comment for its improved tone and assumptions, and note the consequent improvement in the tones of the responses. It is typical for commenters new to Skeptical Science to adopt a combative, assumptive, and scattershot approach that is typical on other sites that have looser commenting policies. The typical result is what you experienced initially. It is also not unusual for such commenters to finally read the comments policy carefully, including the requirement to stick narrowly to the topic of the particular post you are commenting on, and to use the Arguments list (hover over the Arguments link in the horizontal bar at the top of the page to see alternative presentations), and the Search function to find the appropriate thread, read that original post first, and only then comment. Especially helpful is to click on the Newcomers and Big Picture buttons at the top of the home page and follow the suggestions there. When commenters then adapt their approach accordingly, they have a much improved experience. I believe "Eric (skeptic)" had that experience; he seems to enjoy most of his interactions here and his contributions are appreciated by other commenters, authors, and moderators despite his definite planting of at least one foot in the skeptic camp. (Caveat: He seems to be more of a true skeptic than a denier, which is a big help.) Eric should correct me if I have misrepresented his experience.
66172. skeptikal at 02:08 AM on 23 January 2012
       Climate Change Denial and the Media - Banishment of Science Reality
       Tom Dayton & muoncounter, thanks for taking me seriously. Tom, there's quite a lot of links on Tamino's Climate Data Links page you gave me. Should keep me busy for a while. muoncounter, thanks for encouraging me to read the SkS posts that explicitly address my need to be convinced, but I've already been labelled a fake and don't feel all that comfortable here. Does anyone know what I have to do to cancel my membership?
66173. prokaryotes at 00:28 AM on 23 January 2012
       Arctic methane outgassing on the E Siberian Shelf part 2 - an interview with Dr Natalia Shakhova
       How does the methane and nitrous oxide from permafrost thaw and denitrification, affect the ozone layer? "At low latitudes, methane in the stratosphere breaks down into hydrogen oxides, which attack ozone. Nitrous oxide can decompose to form ozone-eating nitrogen oxides. " http://discovermagazine.com/2002/nov/breakozone/ Last year they found a ozone hole at the north pole, at the size of the south pole ozone hole.
66174. michael sweet at 23:26 PM on 22 January 2012
       Climate Change Denial and the Media - Banishment of Science Reality
       Naomi Oreskes has an interesting Op-Ed piece in the Los Angeles Times. She likens Climate Science to a trial and the scientists to the jury. The first two comments were deniers.
66175. John Mason at 23:19 PM on 22 January 2012
       Arctic methane outgassing on the E Siberian Shelf part 2 - an interview with Dr Natalia Shakhova
       Wili, In response to your first question, clearly the methane is being released as a feedback to warming. What I was careful NOT to say was to which bit of the warming: that resultant from the Holocene transgression or that heaped upon it by Mankind. At the moment, we don't know, as Shakhove herself says: the point is we need to evaluate the situation further. How one goes about determining whether the post-1980s abrupt seawater warming reported by Dmintrenko et al is causing this effect I don't know, but I would hazard a guess that should the rate of methane emissions in the coming years be found to be increasing in tune with this extra warming then we should have a pretty good idea, likewise with the ARS data you refer to.
66176. michael sweet at 22:57 PM on 22 January 2012
       A Comprehensive Review of the Causes of Global Warming
       Patanomics, the equation you seek is called a climate model. See the climate model thread which starts with a simple equation just like you asked for!
66177. Glenn Tamblyn at 21:31 PM on 22 January 2012
       2011 Hottest La Niña Year on Record, 11th-Hottest Overall
       AT #1 Possibly missing several things. Between 1910 and 1955 the worlds temperature record was in flux. Initially stations were being added to the Arctic. Then much latter stations were added to the Antarctic. So the temperature record has some significant possible distortions during that period. Also the SST record was distorted due to a discontinuity caused by a shift in the proportion nof nUS vs UK ships involved in SST measurement during the War Years. So one cannot assume that the 1910/40 curve is really the result of an early warming pattern, rather than simply a result of othet factors not well analysed. And without that curve, the longer term pattern has a different meaning.
66178. jyyh at 21:22 PM on 22 January 2012
       How do Climate Models Work?
       As this is a basic article on how climate models work, I'm not sure if my question is on the right place. The last figure shows the observed ice loss vs. the IPCC projection, do you know how much energy this extra melt has taken? I'd imagine it's out of the other parts of the earth system, so a slight overestimate of temperatures could be seen elsewhere in the models. I guess what I mean to ask is, has the heat transport from the tropics to polar areas speeded up, and how could this be measured?
66179. Glenn Tamblyn at 19:16 PM on 22 January 2012
       A Comprehensive Review of the Causes of Global Warming
       patanomics. Not wanting to seem to dump on you, but the idea of a few equations that encapsulate what you are looking for is rather simplistic. The function you are looking for probably has lot more aspects than that, including complex time domain relations. Why do you expect such eqns? Surely the appropriate approach it to take the findings from a wide range of scientific disciplines and combine th0em together. Rather than look for a simple set of eqns.
66180. Jenpalex at 19:00 PM on 22 January 2012
       How do Climate Models Work?
       Does your model predict the slowdown in temperature increase since 1998? Does it have the property of even 'accurate' regression models of increasing forecasting error as fufure forecasting distance increases? By what criteria do you judge the forecasting accuracy of your model?
       Moderator Response: Your questions are misplaced on this thread, because the original post is a basic explanation of how climate models work. Your question belongs on the thread "Models are Unreliable," which you can find by entering that phrase in the Search field at the top left of this page. But read the original post on that appropriate thread before posting your questions, because your questions already are answered there.
66181. Alex C at 16:16 PM on 22 January 2012
       2011 Hottest La Niña Year on Record, 11th-Hottest Overall
       Chris G @23: True, if you assume continuity along the horizontal axis (which, regarding time, makes physical sense, but the data is not presented as a function of a continuous variable). You could of course align any mean with any fractional abscissa, but cosmetically (to use your word) it would make more sense to have an X-year centered running mean actually centered on a year, and not a piece of a year (or, month, and not a piece of a month).
66182. Chris G at 15:10 PM on 22 January 2012
       2011 Hottest La Niña Year on Record, 11th-Hottest Overall
       Alex, Hmm, I'm not aware of any difficulty calculating the mean of an even number of points or any requirement that the endpoints of the running mean has to align perfectly with endpoints of the periods of the base measurement. Time can be considered a continuous variable; the middle of a month exists as surely as the start or end. In minutes, X Y 00:01:00 1 00:02:00 2 00:03:00 3 00:04:00 4 If you are calculating the mean of these points, and consider that Y is the mean of the period from the start of the period ending at X, you get means of 00:02:30 2.5 IDK, in my mind, that is just as valid a point, and could be graphed just as easily as 00:03:00 3 would have been if there had been 5 data points (following the same pattern). Hmm, that is actually not correct. If 00:04:00 is the endpoint of a period of 4 minutes, then the middle of that interval is at 00:02:00. You have to consider time not as points, but as intervals. And, you have to know if the point in the dataset represents the start, end, or middle of that interval. Cosmetically, it could be a little easier to deal with the periods of the base measurement aligning with the period of the calculated mean, but if you can put 2.3 children per couple on a graph, I'm pretty sure you can define a point in the middle of a month. For that matter, months are kind of a poor choice for period; there is not the same amount of time in all months. Nevermind leap years, and leap year February. I'm sure that people that deal with temperature record data have figured all this in, but let's not assume that what's convenient for cosmetics or human thought patterns is a requirement of reality. On the other hand, I'm open to the idea that I missed something. Or, maybe I'm overstating the obvious. Or, maybe I'm just overstating the obscure.
66183. muoncounter at 14:51 PM on 22 January 2012
       A Comprehensive Review of the Causes of Global Warming
       patonomics#29: "I will highly appreciate if anyone refer me to "Climate Science Laws"" The laws you seek are no more than the laws of physics, such as Conservation of Energy, Stefan-Boltzmann, Planck's Radiation Law, Kirchoff's Law of thermal radiation, etc. Do you insist that every sub-discipline have its own unique set of laws? If so, what are the 'Laws of Quantum Mechanics'? If, by your earlier comment, we cannot capture all of quantum mechanics in a single deterministic equation, do you claim to invalidate what is often called the most successful scientific theory we have?
66184. jyyh at 14:08 PM on 22 January 2012
       2011 Hottest La Niña Year on Record, 11th-Hottest Overall
       Then there's the question of how much data is available from the Arctic and Antarctic during the war times, if it was relatively cold in these locations, this could bring the CRU observational dataset down. The topmost snow/ice from Greenland and Antarctic icecore locations should provide some evidence.
66185. Tom Curtis at 13:58 PM on 22 January 2012
       A Comprehensive Review of the Causes of Global Warming
       patonomics @29, it may be a "34% error bound", but it is an accuracy of approximately 99% (3 degree K temperature range at approximately 290 degree K). Whether that is accurate enough depends critically on the reason the temperature is being modeled.
66186. Tom Curtis at 13:39 PM on 22 January 2012
       2011 Hottest La Niña Year on Record, 11th-Hottest Overall
       jyh @20, Foster and Rahmstorf have already used the Southern Oscillation Index instead of the Multi-variate ENSO Index to test the robustness of their analysis, so that aspect should be no problem. Given the removal of exogenous factors, the result should be not a linear trend over the entire century, but a variable curve approximately matching anthropogenic forcings, ie, the green curve in this figure from Lean and Rind (2008): Based on the empirical model produced by Lean and Rind (below), we would expect large excursions from the "anthropogenic" signal in the periods 1910-1915, and 1940-1945, and a smaller excursion in the period 1960-1964. On top of that we would expect small, fluctuations about the anthropogenic signal. I put "anthropogenic" in "shudder quotes" above because Lean and Rind do not model all anthropogenic factors. In particular they do not model Black Carbon, which I suspect was a major influence in the high temperatures during WW2. It should be noted that in the period 1880 to 1940, BC and sulfates found in Greenland ice cores rise to a peak around 1910, before gradually tailing of. The reduction after 1910 would be because of the transition from coal to oil as a major fuel. Because the sulfates and BC are significantly correlated, they would have to a significant extent counteracted each others effects. In contrast, BC from WW2 would come from the burning of cities, and would not have significant associated sulfate emissions. Because of the direction of the prevailing winds, cities burning in Europe would also not have left a significant record in Greenland.
66187. patonomics at 13:22 PM on 22 January 2012
       A Comprehensive Review of the Causes of Global Warming
       We learn the following about Science " Theories are more certain than hypotheses, but less certain than laws." I happen to be involved in 3D heat generating equation calculation and validation in a closed miniature atmospheric calculation in 1990 & 1991 for grain silos. I am amazed by a even 2011 publication which claims only over 34% error bound [(3.1-2.3)*100/2.3] and still claim "model is considered sufficiently accurate and reliable". Then what to expect from real earth atmosphere predictions, where closed system experimentation and observation is not feasible. There gain silo case is as follows
       The standard error of predicted versus observed headspace air and wall temperatures was in the range of 2.3°C to 5.3°C and 3.1°C to 5.5°C, respectively. The standard error of predicted versus observed headspace humidities was around 7%. The developed model is considered sufficiently accurate and reliable to predict air temperature and relative humidity at multiple locations in the headspace of a grain storage silo. What to expect when one claims to see what the scientific literature and data have to say about exactly what is causing global warming I will highly appreciate if anyone refer me to "Climate Science Laws", if there are any, for my assimilation of knowledge as I am getting hunted by close friends who claim there are ready prove & certainty about AGW but could not substantiated by any validated document so far. - If there is none, I do not want any initiative to throw any unsubstantiated articles as references (about certainty) is this regard.
       Moderator Response:

       Grain silos are not good models of the Earth's climate system. For actual results of climate models compared to observations, see the Skeptical Science argument "Models are Unreliable." (Type that into the Search box at the top left of this page.)

66188. barry1487 at 13:08 PM on 22 January 2012
       How do Climate Models Work?
       funglestrumpet@38, what you say is exactly what I imagine is happening. We have for years tried to unlace politics and ideology from the discussion of the science, demanded of ourselves that we maintain a purely scientific argument, and pointed out to the contrarians where they err in this respect. Their perversion of reason is the most frustrating aspect of the general debate, I reckon, and I think the reason-based community has become weary of being primly objective with little apparent effect. At its heart, the debate over climate science is an activist pursuit. It may be we've become tired of covering it with a mask of neutrality, and that it's not enough to "carry on as we are." Tom Curtis@17, agree with all of that. However, the posts you cite are not representative of occasional forays at SkS into areas that are not purely scientific. These are all recent. I believe this is a trend, and the extra latitude in the articles here lately has resulted in some disconnects with the mission statement, which is explicit about devotion to pure science. http://www.skepticalscience.com/about.shtml Technically, the mission statement might be amended. But I just wanted to bring this adjustment in priorities (if such is occurring) to light so that we're aware of it and more effective for being so.
       Moderator Response: [muoncounter] Please take continued discussion of what you perceive to be some sort of 'sea change' at SkS to The Big Picture. You will note that particular thread, originally written in 2010, has a section on advocacy and policy.
66189. climateadj at 13:07 PM on 22 January 2012
       How do Climate Models Work?
       Tom... how astute of you! I simply (mis)described climatoloy for annual variability. My experience is that one can run any 12mth perod thru my program and end up with the same result. Then again, I'd like to see a professional examination of this subject.
66190. jyyh at 12:40 PM on 22 January 2012
       2011 Hottest La Niña Year on Record, 11th-Hottest Overall
       "periods of 1880-1940, 1910 to 1940" I think MEI isn't calculated that far in history, as it takes note of many atmospheric variables not commonly and widely measured before war. But, there's SOI, and as he says it's robust then it seems there should be no reason why this couldn't be done. Aerosol loading may have changed for alterations in ff use, though, i'd imagine
66191. Tom Curtis at 12:01 PM on 22 January 2012
       A detailed look at climate sensitivity
       Eric (skeptic) @75, using your numbering: 1) On the Serial Deleter thread, I gave two criteria under which SkS practice should be considered sub-par: a) That "...not including figure 3b of Knutti and Hegerl has resulted, or facilitated, in misrepresentation of some part of Knutti and Hegerl by SkS"; or b) That "...not including figure 3b of Knutti and Hegerl has resulted in a failure to canvass issues that should have been canvassed in a post on SkS." In case (a), you would have found an example in which SkS practice could be (and should be) criticized in much the same manner as Michaels is criticized in the OP of the "serial deleter" thread. In case (b), you would have found an example in which SkS practice did not rise to the level of misrepresentation, and hence was not so criticizable; but in which it still represented a serious lapse from the standards which we would expect. It is noticeable that you do not criticize the OP in this article on either of these grounds. Instead you criticize it on the much weaker grounds that it contained relevant information. Of course, it does contain relevant information. Fortunately, however, we do not and should not expect articles of any nature to contain all relevant information. Where they to do so, nothing short of a expanded exposition of any scientific paper referred to would be acceptable; for, of course, all the information in those papers is relevant, and so is the background knowledge that could be expected of the scientists to whom the papers are addressed but which cannot be expected of the general public (hence the expanded exposition). Such a requirement would make any blog post extraordinarily long and turgid even by my long winded standards. You may suggest that the information in this case is so relevant that it should have been included, or that the information could have been included simply by including the figure (or both). The second, however, is false simply because the figure assumes background information, part of which I expounded after the bolded "more importantly" in my post 72. Because the figure is easy to misinterpret without background knowledge (and doubly so given the presence of people who would IMO willfully misinterpret it), its inclusion would have required adding at least two paragraphs to the two paragraph section on paleoclimate above, plus additional paragraphs in other sections in that the figure is not restricted to paleoclimate. Given an intent to communicate succinctly and clearly, the additional text required to include the relevant information from the graph was too high a load for the additional information required. And of course, much of the information about certainty is already included in the error bars from figure 3a, so it is not true that the additional relevant information should have been expanded on in the original article. Of course, the additional information is included in the article in the minimal form of a link to the original article by Knutti and Hegerl. Given this, and given the factors mentioned above, while the information in figure 3a is relevant, it was certainly not sufficiently relevant that it needed to be canvassed explicitly in the OP. That fact should lay to rest any suggestion that SkS is applying a double standard with respect to the use of graphs in its criticism of Michaels. 2 & 3) The issue of uncertainty in climate regimes is a major factor when considering a sensitivity analysis in relation to a particular period. It ceases to be a significant factor when a large number of paleo sensitivity analyses are made across a large range of different climate regimes. That is because a robust result found across all paleoclimate regimes almost certainly applies in any particular regime, including our current regime. I know that is simply repeating my point from 72 above, but I do not see anything in what you write that tends to rebut it. Yes there are other non-forcing related factors which adjust the base global average temperature for a given radiative forcing, either by altering the strength of feedbacks, or by altering the heat distribution of the Earth (with greater variation allowing a lower Global Mean Surface Temperature). Changes in land cover and land/sea proportions could also make minor changes to emissivity which would also adjust GMST relative to a particular forcing. But it is extraordinarilly odd that these factors should some how combine to produce the same apparent climate sensitivity when comparing either the pliocene (3 C warmer, low ice, higher sea levels) or the LGM (6 C cooler, much ice, lower sea levels) to the present day. It is even odder that with a climate sensitivity for doubling CO2 of between 3-4 degrees C during non-glacial periods and double that during glacial periods (due to the increased feedback from ice albedo effects) explains 85% or more of the variation in CO2 concentration, as found by Park and Royer (2011). Please note that this is the long term climate sensitivity, ie, the climate sensitivity allowing for meltback or growth of "permanent" ice sheets. In the absence of such ice sheets, that should approximate to the Charney Climate sensitivity discussed in the article above. Hence Park and Royer tends to confirm that the Charney climate sensitivity is in the range of 3 to 4 degrees C, and has been across all geographical conditions encountered in the last 540 million years. Once weatherable land surface is factored in, the primary determinant of CO2 levels is temperature. As Park and Royer show, factoring in weatherable land area allows an even greater explanation of the variance in CO2 levels with a presumed non-glacial climate sensitivity of 3-4 degrees C (figure 10). Hence a climate sensitivity given feed backs excluding long term changes in "permanent" ice sheets of 3-4 degrees C is a very robust feature of the phanerozoic.
66192. Riccardo at 11:20 AM on 22 January 2012
       How do Climate Models Work?
       climateadj use a dice as an analogy. You can hardly predict next result but in the long run you know the probability.
66193. funglestrumpet at 11:18 AM on 22 January 2012
       How do Climate Models Work?
       barry @ 14 What do you recommend then; just carry on as we are watching the world go to hell in a handcart? We see Copenhagen go by in a flurry of missed opportunities and then Durban do the same. We see the sort of tricks that the likes of Monckton, Lawson, Lindzen, Christy, Spencer and Michaels, to name but a few of the denialati, get up to. We see the enormous support given by the fossil fuel industry towards a b.a.u. scenario and nothing much happens to raise that publicly as an issue. We have America, one of the world’s most polluting nations, with a mainstream political party that has climate change denial as a rite of passage to membership. We have articles published here repeatedly reporting how things are just moving from bad to worse and we do nothing, but simply get the science right! Anything else is “Just not cricket, old boy!” Well, to hell with that. I come here to understand the science and this site is excellent at meeting that need. But the reason behind my desire to understand the science is that I am very concerned about the future that my children and grandchildren face. I assume that many others have the same concerns as me and come to the same trough of knowledge for the same purpose. So from time to time I might write something that could be considered advocacy. I make no apologies for that. I will do whatever I can to protect my family and if that is frowned upon, well go on then, frown. My family come before all other considerations. I am not alone in getting exasperated at the lack of action on combating climate change. It was obvious in her excellent article on Methane outgassing in the Arctic that Dr Natalia Shakhova is fed up with the lack of action on the issue. Perhaps she, more than most, can see just how urgent things are, especially if the methane outgassing follows a worst case scenario. She too can see just how much of a hindrance all this arguing about whether the warming is anthropogenic or not is. If it were not climate science, but the science surrounding that of a particular model of aircraft, say, we would have grounded the whole fleet long before now because of the danger posed by continued operation. Yet planet earth can carry on with business as usual. We can always catch another aircraft. We cannot catch another earth.
66194. Tom Curtis at 11:15 AM on 22 January 2012
       How do Climate Models Work?
       climateadj @35, I do not see where you performed a mathematical step in order to examine seasonal variance rather than variance simpliciter. I'm not up on the maths involved, but it seems to me that if you just plot the variance of the data, it may well be dominated by quasi-periodic oscillations such as ENSO, or indeed possibly even by long term trends if seasonal variation is low compared to long term changes in temperature.
66195. Tom Curtis at 11:02 AM on 22 January 2012
       2011 Hottest La Niña Year on Record, 11th-Hottest Overall
       Alex C @18, Tamino writes:

       "For the updated results, rather than use TSI (total solar irradiance) to represent solar variations I used sunspot counts, because they’re easy to get, kept up-to-date, and already available as monthly averages."

       The "easy to get at" and "available as monthly averages" may be particularly important factors in that his updated software passages included a program which gathers the data from the internet, and formats it for you so that you can easily keep the analysis up to date. It may be that the programming task was easier in that respect with sunspot numbers than TSI. Of course, I am speculating, and if you think it is important, you should ask him. What I do know is that in Foster and Rahmstorf (2011), Tamino wrote:

       "To test whether the results might be sensitive to these choices, we also did experiments characterizing el Nino by the southern oscillation index (SOI) rather than ˜MEI, characterizing volcanic aerosols by the volcanic forcing estimate of Ammann et al (2003) rather than the AOD data from Sato et al, and using monthly sunspot numbers as a proxy for solar activity rather than TSI. None of these substitutions affected the results in a significant way, establishing that this analysis is robust to the choice of data to represent exogenous factors."

       That being the case, the switch to sunspot numbers should make no significant difference.
66196. John Hartz at 10:28 AM on 22 January 2012
       How do Climate Models Work?
       climateadj; Thanks for the clarification and the link to your calculations. Alas, I am not qualified to assess the reasonableness of your computations and of your tentative conclusion.
66197. Alex C at 09:55 AM on 22 January 2012
       2011 Hottest La Niña Year on Record, 11th-Hottest Overall
       Tom Curtis @16: I have typically seen 11 year running averages, and thought that it was for much the same reason as that a centered mean cannot be given for an even number of years. I am aware of the solar cycle length average, but the thought that it was the primary driver behind a choice of 11 years hadn't occurred to me before (I suppose it should have, hm?). Thanks for the clarification. I personally found Tamino's switch to sunspot number interesting. I thought that TSI data was updated continuously (daily), why use a proxy instead of the real deal?
66198. Tom Curtis at 09:54 AM on 22 January 2012
       2011 Hottest La Niña Year on Record, 11th-Hottest Overall
       It would be interesting if one of the tech savvy people at this site used Tamino's software to adjust for exogenous factors for the periods 1880-1940, 1910 to 1940, and 1880 to 2011. (I have just made the same suggestion to Tamino, so you may want to hold of to see how he responds.)
66199. Tom Curtis at 09:47 AM on 22 January 2012
       2011 Hottest La Niña Year on Record, 11th-Hottest Overall
       Alex C @13, while the reason for the odd number of months is as you give it, the reason for choosing an approximately 11 year running average is almost certainly to remove the solar cycle. (I suspect your aware of that, and have merely phrased your response to Chris G @10 poorly.)
66200. Tom Curtis at 09:41 AM on 22 January 2012
       2011 Hottest La Niña Year on Record, 11th-Hottest Overall
       Sorry, I forgot to include the link to Tamino's site for those not familiar with it.

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