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Comments 50001 to 50050:

50001. Tom Curtis at 14:30 PM on 13 January 2013
       Greenhouse effect has been falsified
       Wig4@104: 1) A variety of experiments have been performed by people attempting to quantify the strength of the effect of trapping IR radiation by glass in warming greenhouses. Most famously, this was done by R. W. Wood in 1909, who found no measurable effect. The lack of measurable effect has been misinterpreted by Wood and others as a refutation of the atmospheric greenhouse effect. In fact, while some have repeated Wood's experiment and found no measurable effect, others have found a 15 to 20 degree C increase in temperature relative to control when trapping IR radiation. That 15-20 degrees C is, however, less than half of the total increase in temperature. Further, in greenhouses in which the presence of vegetation limits the increase in temperature of the surface, and hence the increase in IR radiation from the surface, the effect will be even smaller. It follows that the prevention of air circulation carrying away excess heat is the major cause of increased temperatures in greenhouses. Ergo, greenhouses primarily work by "by blocking convection" as indicated in the original article. 2) Your argument devolves down to a mixture of garbled facts and outright errors. Let's start with the basics: a) The total upwelling IR flux at the surface is greater than the incoming SW flux times (1-albedo); b) The total upwelling IR flux at the Top Of the Atmosphere (TOA) approximately equals the incoming SW flux times (1-albedo). c) The difference between the upwelling IR flux at the surface and that at the TOA is the atmospheric greenhouse effect; and it can only exist because components of the atmosphere absorb IR radiation from below (lower atmosphere and or surface). c') If components of the atmosphere did not absorb IR radiation, then by necessity the upwelling TOA IR flux would equal or exceed that at the surface, resulting in no atmospheric greenhouse effect. c") If the atmosphere did not absorb more upwelling IR radiation from the surface than the atmosphere alone emitted at the TOA, then by necessity the upwelling TOA IR flux would equal or exceed that at the surface, resulting in no atmospheric greenhouse effect. c"') If the atmosphere absorbs more more upwelling IR radiation from the surface than it alone emits at the TOA, then be necessity the upwelling TOA IR flux will be less than that at the surface, and hence there will be an atmospheric greenhouse effect. From the points above, it is clear that atmospheric absorption of IR radiation is necessary for the existence of an atmospheric greenhouse effect. Ergo, as a simplified account, saying that the "atmospheric greenhouse works primarily by blocking thermal radiation" is sufficiently accurate. Radiation of IR radiation by the atmosphere reduces the strength of the atmospheric greenhouse effect, and in the special and unusual case where the atmosphere is warmer than the surface, will result in a cooling of the surface. Typically, however, the atmosphere is cold enough that there is a substantial atmospheric greenhouse effect, and the colder the atmosphere the stronger that effect will be. I refer you to my article, Warm Earth, Cold Atmosphere for a more detailed discussion, including examples of "proven, measured quantifications" of this effect. Finally, I note that IR radiation from the atmosphere is restricted in the range from which it will radiate, with a large a smaller atmospheric window from which there is essentially no radiation (or absorption) except in the presence of clouds. Further, I will note that the atmospheric greenhouse effect is so-called for historical reasons, and nothing save a foolish pedantry is served by railing against history.
50002. Ray at 12:19 PM on 13 January 2013
       Met Office decadal forecasting explained: the reality
       Looking at Figures 2 and 3. the slope at the later portions of the white line on the two graphs are markedly different, a difference that I don't think has been discussed here. Exactly what is that white line showing and why the differences? Presumably these differences are due to the differences between HadGEM3 and HadCM3. Is that correct? If so and as HadCM3 has been used in earlier predictions, is it not possible that in the future, predictions from HadGEM3 will be shown to be different from those of the succeeding generation of climate models? Should the answer be in the affirmative this could indicate the science of climate change may be somewhat less settled than has been suggested. Whatever, I'd very much appreciate elightenment on the questions I've asked re the "white line"
50003. Flakmeister at 10:27 AM on 13 January 2013
       Nature Confirms Global Warming and Temperature Record Accuracy
       One picture is a 1000 words or so... http://xkcd.com/54/
50004. Phil at 10:26 AM on 13 January 2013
       Resolving Confusion Over the Met Office Statement and Continued Global Warming
       Rob @81 I wonder whether people like smerby, don't appreciate the full extent of the sources of evidence for climate sensitivity. In other words smerby might be assuming (sorry if I'm putting words into your mouth, smerby) that future temperature rise projections come from a climate sensitivity value that is solely determined from the temperature record for the last 30 years and therefore such projections assume that there are no long term (multi-decadal) oscillations. (Conversely, of course, smerby would then believe that if multi-decadal oscillations did exist and the last 30 years was on an up-swing, then future temperature rise projections would be over-estimated). In actual fact only a very few of the methods of determining climate sensitivity use the recent temperature record, and so the supposition of a multi-decadal oscillation does not alter the long term trend.
50005. Albatross at 10:21 AM on 13 January 2013
       Met Office decadal forecasting explained: the reality
       The reality, of course, is very different from how those in denial about AGW and fake skeptics are trying to spin this story. As always, it is best to go to the source. Here is a BBC Radio 4 segment in which they try and set the record straight, but without actually bringing themselves to admit they messed up or apologizing to the Met Office. I would encourage people who are still convinced in the myth being promoted by those in denial to listen to the words of Prof. Julia Slingo, who is the chief scientist of the agency who actually made the experimental forecast.
50006. Doug Hutcheson at 10:16 AM on 13 January 2013
       A Brief Note on the Latest Release of Draft IPCC Documents
       Mal Adapted @ 25, I don't quite agree with your final sentence. I don't think anyone expecting BAU is in denial, necessarily. The problem is more subtle than that: I think people in general are optimists, who don't have the time to think through all the issues. I have a more pessimistic view, based on my understanding that the IPCC chooses to err on the side of caution in its pronouncements, so that reality is likely to be somewhat worse than they care to admit. As for BAU, I predict most nations will continue as they are now, for as long as they can, until various crises overwhelm them. I base that on a combination of two human traits: greed and optimism.
50007. Tom Curtis at 10:07 AM on 13 January 2013
       Resolving Confusion Over the Met Office Statement and Continued Global Warming
       smerby @80 writes:

       "[T]he records also show that the leveling off should last for another 20 years."

       The record shows nothing of the sort. I have just finished an analysis of how successfully you can predict future temperatures from trends of a given length. As it happened, for a ten year prediction, a 16 year trend performed significantly worse than simply adding 0.085 C to the current month's temperature. That makes the 16 year trend a very poor predictor of future temperatures. The best prediction from linear trends is obtained by adding 0.046 C (the mean under projection) to the 24 year trend projection. That yields a projection on HadCRUT4 data for 2022 of 0.744 +/- 0.391 C anomaly relative to 1961-1990; and approximately a four in five chance of exceeding the current consecutive 12 month record. Far better than any prediction from recent trends, however, is a prediction from physics. Here for example, is a comparison of the prediction from 16 year trends and that from CO2 forcing alone: As you can see, prediction from trends performs far worse than prediction from physics, even when you only include one (albeit dominant over the long term) forcing. When you include all forcings plus ENSO, as Kevin C does, there is not contest between the predictions made from physics, and those made from trends only: Yet you want to predict a 36 year pause in global warming from a cherry picked 16 year trend in contradiction to the physics? As I said, your claim has no basis.
50008. Wig4 at 10:01 AM on 13 January 2013
       Greenhouse effect has been falsified
       "Intermediate" level article copy contains this passage : quote ...//... A glass greenhouse works primarily by blocking convection, and an atmospheric greenhouse works primarily by blocking thermal radiation, and so the comparison is not exact. ...//... This is blatantly wrong information. (1) ((A glass greenhouse works primarily by blocking convection)) Nonsense. Glass greenhouse works promarily by blocking IR with wavelenght above 3000 nm from leaving. (This is related ti SiO2 glass, other glass-types have different IR-block out limits) It's reflected inward again. This causes partial reabsorption by solid materials, re-emitting IR, reflected again, and again and again in this enclosed space, until losses are getting effective through conduction. (air-glass-air, and I calculate these loss rates 'everyday' through my practise... 99,9% correctly calculable...) Convection originating from air-contact with the solids is heating the air, not the radiation. That is the glass-glasshouse effect. Of coarse the heated air will leave if you open windows, but that if childish talk when explaining physics of the greenhouse effect. The total heat capacity contained in the enclosed air, however, is futile compared to the heat capacity of the solids. That explains the extreme speed of the glass-greenhouse effect. Ventilation of a greenhouse will lower very little of the temperature gain on the solids. The re-re-reflexion mechanism is still working. Only the air temperature, by ventilation, is fooling us we broke down this greenhouse effect. Nonsense, it goes on. We're only evacuating the resulting air convention heat, witch has, as said, a very low heat capacity. (Only water vapour contains a higher heat capacity, due to it's latent heat energy content, not temperature.) I'm really shocked to find such nonsense written down in presumed "intermediate what science says". Because science never said such a thing. Where is that article sourced? A journalist's sensation box ? .... By the way, I see Ned and others, all over this discussion, play with the notion quote ...//... confused about the distinction between "near infrared" and "thermal infrared" wavelengths ...//... While these terminologies are rather useless in science, when describing thermodynamic processes. We quantify only, we don't play with words. (This whole discussion lacks quantification, btw.) Sun radiation boosts a serious amount of direct molecule activating IR-radiation (roughly 1000 - 5000 nm), from which up to 3000 nm is passing glass. At the total 45% IR present in sunlight, at least 30% is contributing to direct molecule vibration activation, "heat". Because this depends to the receiving molecule, the global % contributing directly to heat excitation from the sunlight is not exactly definable. Earth-born IR-radiation peeks at about 10,000 nm, but starting only over 2500 nm. This explains fully the "trap" of reflexion behind Si02 glass. (2) ((an atmospheric greenhouse works primarily by blocking thermal radiation)) Nonsense again. Atmospheric "greenhouse" (fake terminology use, grown over the years.... never use the same terminology for 2 totally different physical systems...) works primarily by absorption of IR-radiation. In some stage of this discussion, I saw the 100% correct statement that all molecules of whatever kind, within a gas mix, in one location, equalise onto the exact same temperature, though the collisions among each other. This means, that if one kind of molecule warms up faster then another kind of molecule, related to a specific IR waverlenght, the resulting accumulated heat is extremely fast redistributed over all at random neighbour molecules. First physical concern is = available heat capacity of the mixed gas. (This capacity always if futile, compared with solids on earth. Only the watervapour ice cristals physics provide something of non-futile proportions) If RE-emitting of radiation (different wavelenght, in most cases ?) is happening, now, the original captator is in minority position within the total gas composition (including suspended ice crystals.) As said, RE-adiation can happen in all kind of different wavelenghts, through this mechanism. I like to see proven measured quantifications within this real-reality complex process, not wet-finger work.) Apart from RE-radiation, chemical driven heat converting processes can take place. On this level , all 5 heat dissipation mechanisms are active at the same time. Convection, conduction, radiation, latent energy conversion, chemical energy conversion. I read zero.dot.zero comments, until now about this complex reality. (From both sides of the discussion table, by the way.) I'm not an active scientist. I have studied, however, thermodynamics, in my accademic years, and I feel horror when anyone is talking gibberish within this domain. I read ridiculous theoretic simplicications of those very complicated thermodynamic processes within the so called "peer revieuwed scientific majority", and I encounter just as much riduculous stupidities from the opposition side. It is sad. Fact is that at least all basic laws of thermodynamics have been proven correct. (-snip-) Anyway, greetings to all, and my wish to get this into real science backed discussion. (I just touched a microscopic detail within the whole topic... ;-) )
       Moderator Response: [DB] Please familiarize yourself with this site's comments policy (link adjacent to the comment box). All caps usage is forbidden (converted to lower case in this instance; future violations will ensure moderation up to and including deletion of the entire comment). Inflammatory tone snipped.
50009. Nick Palmer at 09:48 AM on 13 January 2013
       16  ^  more years of global warming
       I was quite enjoying the comments bunfight on the Youtube version. Rob Honeycutt was answering every silly comment with real science and I was chipping in with my down-home analogies to try to get through to the worst of them the difference between large cyclical variations and small cumulative forcings - waves vs tide on a beach and over-eating averaged over decades vs binge eating/crash diets. Most "anything but CO2" commenters seem incapable of understanding why picking start/finish times on a proper graph can give a totally false impression of the underlying trend. Sometimes, simple analogies like those above can get through.
50010. Doug Hutcheson at 09:31 AM on 13 January 2013
       Met Office decadal forecasting explained: the reality
       chriskoz @ 13, it is available from the Firefox extensions searchable when you navigate to Tools/Add-ons. I have had it for ages and it seems pretty reliable, although it relies upon users to add their own ratings when they encounter problems with a particular site. Mods: apologies for the off-topic post, but I don't see a way to email chriskoz privately - is that possible?
       Moderator Response: [DB] Request sent on your behalf.
50011. rugbyguy59 at 09:25 AM on 13 January 2013
       16  ^  more years of global warming
       Thanks Rob. And I certainly understand why the comments were blocked. I think the moderation had created a tone that was far better than the other videos on climate change. But I can only imagine it was a nightmare. Chris Mooney is likely correct and it is very difficult to maintain a calm, rational tone on a forum like YouTube, although you do it better than most. The only thing I wondered was if the number of comments might play a role in how highly YouTube recommends videos to those looking at similar stuff. However it looks like the number of views continues to climb.
50012. gws at 08:41 AM on 13 January 2013
       Resolving Confusion Over the Met Office Statement and Continued Global Warming
       smerby, can you give some evidence for these assertions: "Records of global surface temps and sea surface temps going back to the late 1800s support the current leveling off trend and the records also show that the leveling off should last for another 20 years. I know the current trend can be attributed to noise but is 1/3 of a climate cycle and could continue the next 20 years." Did you get that from the scientific literature or some blog site?
50013. vrooomie at 07:55 AM on 13 January 2013
       Resolving Confusion Over the Met Office Statement and Continued Global Warming
       smerby, first let me say thanks for returning to the discussion, with what appears to be an open(ed) mind: It does appear that you are trying to get past prior denialist fake talking points. That said, what you still call "leveling off" to me, and statistically, isn't so much a 'leveling' but a tendency toward a less steep slope.' It's not just a semantic point, but rather a more precise science-language-based way of interpreting the data. "Leveling" would be a slope of near zero, and that is not what we're seeing, especially overall, if we examine all sinks of downwelling radiative energy. I think I can fairly speak for most, if not all, climate scientists and those who are deeply and constructively engaged in the field: No one is trying to 'scare' people, per se, but we have reached a point--again, supported by *many* lines of evidence--where we simply do NOT have any more time to wriggle about, till we know 100% of what can be known. Sir Paul Nurse's takedown of Delingpole comes to mind, inasmuch as a consensus of the globes experts have arrived at essentially the same position, that the confidence level of the "A" in GW being real to a factor of 2 sigma. Yes, we need to keep level heads, and we all here are trying; however, at the *very* same moment, we are also deeply troubled by what we see, both in the progression of what we pretty well knew 20 years ago, and the damage that is being caused by the denialati, watts among one of the worst. Everything, and I mean ~everything~ that can be brought to bear upon this issue---solar, wave energy, geothermal, efficiency (conservation witha capital C, foremost), sustainable farming, shipping, and distribution factors, the list is way too long to continue here. the facts we need are here, they are vetted by somewhere north of 14 *thousand* scientists and organizations, and they all point to the same issue. We are running out of time. By all means, keep asking questions, and I can guarantee you will find an answer here at SkS, but also, please consider stopping the spread of FUD, in any way that you *might* be involved in: The stakes of inaction are just getting too high for that. It's that frustration that you may see sometimes bubble to "our" surface. If we don't, the stress the global population WILL experience, dealing with a 2C to 4C rise in surface temps, will go ~waaaay~ beyond any stress you currently sense.
50014. Mal Adapted at 07:41 AM on 13 January 2013
       A Brief Note on the Latest Release of Draft IPCC Documents
       CBDunderkson:

       I expect it to be business as usual... except that you'd park your car over an induction charger in the driveway each night rather than periodically going to something called a 'gas station'. Long term there'd also be vast health and economic benefits, but there are too many variables in how those would play out to predict changes on everyday life.

       That's certainly an appealing vision. But as educated people (I mean the participants in this ongoing discussion), surely we all understand that the environmental disasters we confront -- AGW, biodiversity loss, overuse of fresh water, depauperation of the oceans,and on and on -- are costs of the production of economic goods and services, hitherto held external to the prices we pay for them? If the destruction is to be halted, and human society is to become sustainable, the externalities must be internalized. When that's accomplished, prices for all goods and services will rise, for the luxury and leisure we all (on average, at least) enjoy if not for basic necessities. We've been drawing down the world's natural capital on credit, but now we've got to start paying as we go. I swear I'm not going Lomborg on you all, but I don't believe the world's poor will allow the price of food, clothing and shelter to soar ever farther out of reach. Either we will pay our share and theirs too (willingly or otherwise), or the liquidation of natural capital will continue. In the long term, we can hope that keeping all production costs internal will drive producers to use resources and energy more efficiently; but eventually a limit will be reached, and efficiency imposes costs of its own in any case. Into the foreseeable future, we will consume less, or pay more. I'm sorry, but anyone thinks business as usual can go on is in denial.
50015. Rob Honeycutt at 07:22 AM on 13 January 2013
       Resolving Confusion Over the Met Office Statement and Continued Global Warming
       smerby.... The problem is, increasing levels of CO2 represent increasing radiative forcing. Regardless of the signal you see in the surface temperature data, it's the change in forcing that is the problem. If there is no reduction in radiative forcing, that just means when the surface temperature does return to the long term trend, it's going to do so more abruptly.
50016. smerby at 06:43 AM on 13 January 2013
       Resolving Confusion Over the Met Office Statement and Continued Global Warming
       Good points all. I see leveling off trends over the past 10 years with global surface temperatures, sea surface temperatures, and OHC down to 700 m. OHC down to 2000 m has not leveled off and continues to warm so that is where the global warming is. Records of global surface temps and sea surface temps going back to the late 1800s support the current leveling off trend and the records also show that the leveling off should last for another 20 years. I know the current trend can be attributed to noise but is 1/3 of a climate cycle and could continue the next 20 years. I understand that each leveling off period is warmer than the past and could be attributed to increased C02. These are periods that we can bear down on finding alternative energy sources without stressing people.
       Moderator Response: [RH] Fixed image widths.
50017. Kevin C at 06:38 AM on 13 January 2013
       Resolving Confusion Over the Met Office Statement and Continued Global Warming
       Actually there's the core of an interesting question in Smerby's #72. Let me pose it more precisely: Based on our current understanding of the temperature record, what would it take to keep temperatures within 0.05C of the current decadal average for another 15 years? Now the answer should be obvious. We would need either: a) A series of strong volcanic eruptions, or b) A grand solar minimum and a rather greater corresponding change in background than is reflected by the current consensus(1), or c) An increasingly negative ENSO state, or d) The climate to start behaving in a way rather different to the way it has behaved for the last 35 years (simple model) or 130 years (forcing model). A solar minimum doesn't look like it is up to the job, and we don't have a means to forecast volcanoes, so we're stuck with rolling the dice on those or hoping for a drastic change - either for ENSO to start behaving in a way it hasn't before, or for the relationship between temperature and forcing+ENSO to break down. Of course there's no reason it should break in a way that helps us. My turn for an analogy: That seems to me like walking off a building and hoping for a change in the law of gravity before you hit the ground. (1) You can still find a lot of old TSI graphs with very large changes between the Maunder minimum and today. These do not reflect the current consensus.
50018. william5331 at 06:24 AM on 13 January 2013
       2013 SkS Weekly News Roundup #2
       So far, predictions, such as the rate of decline of Arctic ice have been surpassed by reality. http://thinkprogress.org/climate/2012/12/06/1293011/noaa-climate-change-driving-arctic-into-a-new-state-with-rapid-ice-loss-and-record-permafrost-warming/ The next little surprise Giya may have in store for us is the rate of melting of the Greenland ice sheet. http://mtkass.blogspot.co.nz/2012/11/greenland-melting.html
50019. Bob Loblaw at 06:22 AM on 13 January 2013
       Resolving Confusion Over the Met Office Statement and Continued Global Warming
       To extend Sphaerica's house analogy, the deniers are standing next to the fridge, and every time the door opens and a bit of cool air spills out, they say "see? The house has stopped warming!". In spite of the fact that the fridge is simply moving energy from the air inside the fridge to the air outside the fridge (back coils) - much as ENSO mostly just shifts heat around from one part (the atmosphere) to other parts of the globe (oceans).
50020. Bob Loblaw at 06:18 AM on 13 January 2013
       Resolving Confusion Over the Met Office Statement and Continued Global Warming
       Clyde@31: Well, if the comment was behind a paywall (others have pointed out how to get around that), then the reply is too, so I presume that you had not read the reply, either. Posting a link to a paper/reply that you haven't read, presenting it as rebuttal to another paper/comment that you haven't read strikes me as rather odd behavior. As for wanting the source of the data in the figure, then you should have asked that to begin with instead of wasting people's time with ill-formed questions. Unless, of course, that is your goal.
50021. Bob Lacatena at 05:54 AM on 13 January 2013
       Resolving Confusion Over the Met Office Statement and Continued Global Warming
       72, smerby, Also note that every bit of carbon we add to the atmosphere is like turning the thermostat up -- but it's broken, so it can't be turned down. If you turn your thermostat up to 100 degrees and then break it, your house won't jump up to 100 degrees in minutes. If it starts to warm and you turn some fans on to make it seem cool, circulating the air better around the house, that may mask the problem but it's not going to change anything in the long run. Your house is going up to 100 degrees and you can't stop it unless you fix the thermostat (and in this case there is no possible way to fix the thermostat -- there is no possible way to extract the CO2 from the atmosphere once it is there). Any supposed "slow down" in global warming isn't because these years of CO2 emissions are somehow less powerful than other years. It just means that other, impermanent factors are obscuring the effects of CO2 -- temporarily. So, if a quiet sun, Chinese aerosols, and an unusual series of La Niña events minimize warming, and then all of those factors go away, or if those factors never existed to begin with, it doesn't matter. The planet will still reach roughly the same temperature in roughly the same amount of time. So this doesn't buy us time. On the contrary, it lets deniers pretend that they can ignore the problem, wasting precious time that is turning a solvable, manageable problem into an "oh-no-oh-my-God-oh-shoot-what-are-we-going-to-do" panic, because people are going to weight until it's too late.
50022. Bob Lacatena at 05:47 AM on 13 January 2013
       Resolving Confusion Over the Met Office Statement and Continued Global Warming
       smerby, We're not in a flat line. That's a denial fantasy that has been debunked repeatedly. Look here.
50023. DSL at 05:00 AM on 13 January 2013
       Resolving Confusion Over the Met Office Statement and Continued Global Warming
       Not feeling like responding to my questions, smerby? Ok. There is no "buying time." Global warming, as has been noted . . . and noted . . . and noted, has not stopped. The ocean heat content trend has shown no hiatus period, and it represents 92-3% of the global energy anomaly. That energy will return to the surface eventually, as it must. The time to do something was always "now." Why should we wait for a few lower-trend years? Develop alternative energy now. Cut energy use now. Buy simple when possible. Buy local when possible. Save the energy for things that have lasting value.
50024. Dikran Marsupial at 04:54 AM on 13 January 2013
       Resolving Confusion Over the Met Office Statement and Continued Global Warming
       @smerby There is more to global warming that global surface temperatures, there is also the oceans, which have continued to warm. The oceans have a much greater heat capacity than the land, so if the land doesn't warm but the oceans do, then no time has been bought at all. Secondly, trends with cherry picked start dates are pretty meaningless, they are not even statistically significant evidence that surface warming has actually slowed. There is a very good chance you are just seeing noise masking the underlying warming.
50025. smerby at 04:14 AM on 13 January 2013
       Resolving Confusion Over the Met Office Statement and Continued Global Warming
       Question here, based on the global surface temperature record since the late 1880s, could the current flat line we are in continue for the next 15-20 years before warming resumes. If so, would that not buy us time to develop affordable alternative energy sources?
50026. heb0 at 03:52 AM on 13 January 2013
       16  ^  more years of global warming
       At first I also thought disabling comments was a poor choice (I can already hear the cries of "SkS silences discussion!"), but when I saw that there was a prominently-displayed link to the comments section here, I changed my mind. In my experiences, talking about climate on YouTube is a nightmare. The character limits mean you end up posting as many as a dozen replies to explain a single idea, and the reply system, while better than it once was, still makes it difficult to follow the conversation. Registering an account here is quick and simple, so that's not a sufficient excuse for anyone who wants to also claim any sort of interest in the discussion. The strategy, while also likely simplifying moderation, might also work to draw in more people like me, who don't have a great degree of knowledge or formal training on climate science. That would be a great thing because SkS, while becoming more and more widely read, still seems to mostly attract commenters who are either quite familiar with the subject or are so invested in their pseudo-scientific ideas (and sometimes conspiracy theories) that they aren't likely to learn much. Maybe a YouTube presence can change the audience for the better.
50027. Rob Honeycutt at 03:39 AM on 13 January 2013
       16  ^  more years of global warming
       Rugbyguy... We certainly appreciated your contributions on the Youtube channel comments. We discussed internally how to manage the comments on the channel and, basically, Youtube's system is just not set up for moderation as it's done here at SkS. John would have to give out his password to multiple people and every moderation action would be done as if John were doing it, regardless of who actually did it. It would be a huge land mine of potential conflicts. And on top of that, it just doubles the work of moderation when we have two discussion threads; one here and one on Youtube. Ultimately, we decided, any video we post will also have a blog post here connected to it. All the people on Youtube (skeptics included) are welcome to post their thoughts and observations here. Chris Mooney has this recent article out discussing how the tone of a comments section can act to polarize people when commenting goes negative. Youtube is rife with hyper-negative comments threads, especially on the climate issue. We would like to avoid driving people apart. We would prefer that people come here where we can administer our policies of keeping the discussion on topic and about the science, without personal attacks. My sense is that most of the guys who were commenting on YT will not come here and participate. SkS has proven over and over again that skeptics can participate in discussions, but this is a more challenging atmosphere due to the fact that there are well informed people here and the commenting policies are strictly enforced. Those who are just looking for a fight will do well to keep their commenting limited to YT channels. Those who want to participate in substantive discussions should be more than willing to participate here.
50028. Kevin C at 02:14 AM on 13 January 2013
       No warming in 16 years
       I can give a partial answer to that. On longer timescales you can't approximate the human contribution as linear, so you need to use a method which takes into account radiative forcing. The simplest approach is to use the 1- or 2-box model method of Rypdal to find the response function which maps radiative forcing onto temperature, plus the El Nino term. If you do that (using the GISS forcings and GISTEMP) on 1880-2010 then you get this:
       While limited to annual data and finishing at 2010, the model shows the same slowdown post 1998, and for the same reason as in the video - the trend in ENSO. In fact the ENSO term is almost identical (marginally larger) to the value used in the video. This very simple model (20-30 lines of R or python) gives a very good fit of temperature from forcing and ENSO without invoking any multidecadal oscillations with an R2 or 92%. On the basis of this analysis at least there is no justification for invoking longer term climate cycles. That would seem to settle the issue, however the case isn't completely closed. The result does depend on the choice of forcings. If instead you use the Potsdam forcings, the ENSO term is the same so the conclusions of the video are unaffected, but there is room for a small contribution from a multidecadal oscillation. I've been looking into the differences in forcings and understand some of the issues, but there are others I need to track down. One other slight complication - there was a slight reduction in the forcing trend in the early '90s, I believe related to the phaseout of CFCs. That should also produce a slight change in temperature trend. But it's probably too small to detect over a 20 year period.
50029. jake7351 at 01:04 AM on 13 January 2013
       Resolving Confusion Over the Met Office Statement and Continued Global Warming
       Nice to see a youtube post. Have thought for a long time that sks should set up a channel (not under John Cooks name) and post a ~monthly vid (would much prefer a quality monthly vid than poorer quality weekly vid). I think alot of my friends are interested in the science of climate change to watch a 10min sks vid every month, but not interested enough to become a regular sks (or realclimate or CSIRO etc) reader
50030. John Russell at 22:09 PM on 12 January 2013
       Met Office decadal forecasting explained: the reality
       The commonly seen denial meme that suggests anything involving models must be wrong/suspect (exemplified perfectly by William @#1) is based on a complete lack of understanding of what a 'model' is, in the scientific sense of the word. Here is a useful, simple primer which is a good starting point for anyone at a basic level of understanding (with a number of useful links at the end).
50031. Philip Shehan at 21:19 PM on 12 January 2013
       The Y-Axis of Evil
       Another update on D Boehm/Smokey (Now calling himself D Boehm Stealy) He appears to have "pulled his head in skightly since this was posted on WUWT. perhaps someone over there has had a quiet word to him. Philip Shehan says: January 11, 2013 at 2:30 pm moderator: regarding your comment: Philip Shehan says: January 11, 2013 at 1:15 am (reply -There are numerous moderators. Speculating about motives is not welcome. ~mod) I am aware there are many moderators. I did not assume or suggest anything else. That said, I apoloogise for any offence caused to moderators who I am sure do their job honestly, diligently and impartially. I was critical of the behaviour of only one person, who appears to be a moderator. This person is commenting on the posts of others when those posts have not appeared and that is clearly unnacceptable. The fact that the suppressed comment was addresed to this person,who may have been acting as moderator at the time, gives rise to the suspicion that the supposedly impartial umpire is in fact a player who is rigging the game. That possibility should be alarming to everyone.
50032. chriskoz at 20:29 PM on 12 January 2013
       Met Office decadal forecasting explained: the reality
       Doug @11, Please provide the location to your addon, I'm very curious... As for 'the ausralian's article, I simply don't have time to waste for reading it. If I had to opine it, I'd violate the coent policy with my choice of words, so no, thanks.
50033. Sapient Fridge at 19:41 PM on 12 January 2013
       Met Office decadal forecasting explained: the reality
       In the Australian article Davie Whitehouse of GWPF wrote: "the so-called sceptics who were derided for questioning them were actually on the right track" But back in 2008 the Australian was publishing articles predicting rapid cooling and an ice age. Given current weather events I would suggest that those particular 'sceptic' predictions were most definitely not the right track... The Australian will publish anything as long as it denies AGW.
50034. curiousd at 19:10 PM on 12 January 2013
       Greenhouse effect has been falsified
       Further digging around leads me to conclude that the 265 degrees I get in tropics using Modtran for an "effective" radiating temperature is about right. Maybe I am starting to get this stuff.
50035. Doug Hutcheson at 18:22 PM on 12 January 2013
       Met Office decadal forecasting explained: the reality
       Lars Karlsson @ 10, I followed your link to the Australian article, but I have installed a Firefox add-on called 'Web Of Trust', that warns me if I navigate to a site with a poor reputation. Sure enough, I received a warning that the site had been rated 'untrustworthy' by other users. What's this? A mainstream media site untrustworthy? Well, I am surprised. (/sarc) Taking heed of good advice, I did not bother over-riding WOT to read the article. ROTFLMAO. "8-)
50036. Lars Karlsson at 17:18 PM on 12 January 2013
       Met Office decadal forecasting explained: the reality
       Here is a link to the article in the Australian that doesn't require subscription. They heavily rely on the not very reliable David Whitehouse of the GWPF.
50037. rugbyguy59 at 15:48 PM on 12 January 2013
       16  ^  more years of global warming
       Gents, I this is truly an excellent presentation. It's a shame the comments have been disabled on YouTube. Your were certainly engaging most of the big pseudo-skeptics in that milieu. The comments policy was helpful in maintaining reasonably civil discussion. However, I would imagine the number of comments were a bit much to moderate. But once again from someone who visits the site constantly thank you all. It is most helpful.
50038. Tom Curtis at 15:09 PM on 12 January 2013
       Met Office decadal forecasting explained: the reality
       newairly @8, The Australian is a disgrace. Its repeated inaccuracies in reporting, not just on climate change, make it little more than a propaganda rag, IMO. With regard to that particular article, they write: "On one analysis, the forecast confirms what many people have been saying for some time. Global warming effectively stopped 17 years ago and, if the new forecast is accurate, that "pause" will be extended to 20 years." By my analysis, made not by simply eyeballing the chart, but by digitizing it and analyzing it, the new predictions while lower than the previous predictions, predict that 4 out of the next 5 years will break the current HadCRUT3v annual global temperature record. Not only that, but the temperature trend from December 1996 will increase by a factor of five relative to the current trend from that period, said trend being much ballyhooed as "no warming". The only possible way these figures can be treated as extending "the pause in global warming" to twenty years is by pure spin. The deniers are taking us for fools; and in the Australian's "Environment Editor" have found a fool ready to swallow any claptrap they put out without analysis and without thought. Year 1961-1990 1971-2000 1998 0.529 0.411 2013 0.503 0.385 2014 0.544 0.426 2015 0.578 0.46 2016 0.587 0.469 2017 0.541 0.423
50039. curiousd at 13:02 PM on 12 January 2013
       Greenhouse effect has been falsified
       This last comment by Sphaerica leads me to check out with you folks my latest delving into Modtran as an educational tool. 1. Used default settings except looking down from 16 km. This means above most convective heating (Forster 1997).I have found that at equator 17 km is about coolest atmospheric layer. 2. My plot of the change in outgoing flux per doubling of CO2 also had a maximum at 16 km, using 1 km increments. 3. At 17 km the narrow, by Doppler, not pressure, broadened, upward going emission peak due to upper atmospheric CO2 had become manifest in the saturation region of the bending mode absorption. So another reason to stop at 16 km. Default CO2 is 375 ppm. No relative humidity. 4. Using a digitizing program I measured the areas under the 260 K black body peak AND the computed absorption spectrum including the large bending mode dip and the smaller ozone, H2O contributions. I use the 260 K curve to correct the real curve for issues in correctly digitizing the high and low wave number limits. Both curves integrate to a bit under the Stefan Boltzman formula if we assume 260 K but the real curve is definitely somewhat greater in equivalent temperature than 260 K I am using as a reference. I don't think the real curve corresponds to over 265 K but I cannot take the time to get really good statistics, and this is digitizing by eyeball. 5. Conclusion.....Yes indeedy, the earth looks - from the Modtran vantage point of 16 km - like a 260 plus something K black body in the tropics. Not unreasonable that integrated over the globe one might thusly get 255 K? I am interested in developing a lab exercise thereby. Comments?
50040. newairly at 12:18 PM on 12 January 2013
       Met Office decadal forecasting explained: the reality
       The Australian newspaper Australian article today has a story which, in part, claims that global warming stopped 17 years ago and this new analysis extends that to at least 20 years. This is despite also quoting from the Met Office response!
50041. Doug Hutcheson at 11:33 AM on 12 January 2013
       A Brief Note on the Latest Release of Draft IPCC Documents
       CBDunkerson @ 23, I agree that stopping use of FF for electricity generation and transport would see the increase in atmospheric CO2 slowed and, perhaps, it would start to reduce. I am not refuting your claim that CO2 would start decreasing: I just don't have the figures at my fingertips, so I will have to do more research to identify whether turning off the pumps would see CO2 levels go into reverse. According to the EIA

       During the past 20 years, about three-quarters of human-made carbon dioxide emissions were from burning fossil fuels.

       Energy-related carbon dioxide emissions, resulting from petroleum and natural gas, represent 82 percent of total U.S. human-made greenhouse gas emissions

       So, 75% of our emissions are from fossil fuels and (taking the US figure as representative of the world as a whole, which may be wildly incorrect) 82% of that 75% is from burning FF for energy. That means 61.5% of our total emissions are from energy use. If we could stop burning FF for energy, worldwide, today, then my inexpert understanding is that atmospheric CO2 concentrations should start a (slow) decline and the total carbon in the atmosphere may remain below the 2°C threshold. As I understand it, the oceans and other vectors of sequestration are absorbing about half our emissions (making the oceans more acidic in the process). If this is correct, it follows that cutting worldwide emissions in half and maintaining that new level constantly, would see atmospheric CO2 levels remaining at their current level. If we cut by the 61.5% I mentioned above and maintain that new level, then I expect CO2 levels would start to decrease. I do not know whether this decrease would be negated by the oceans outgassing CO2 as the partial pressure in the atmosphere changed. My point is that the key metric is the amount of CO2e in the atmosphere. In order to keep this metric within the bounds of a 2°C rise in GST, while continuing to give Annex 2 nations the emissions we have agreed to, Annex 1 nations would have to decarbonise totally (not by just 61.5%), crippling the global economy. All the above is back-of-an-envelope calculation and I am sure I am not accurate with the figures. I certainly do not mean to refute your claim and sincerely hope you are right. Unfortunately, I cannot imagine the 'real world' is ready to decarbonise by the amounts I have suggested and the Annex 2 nations are certainly not going to hold their emissions static at today's levels, so I think we have a snowball in hell's chance of staying below 2°C, which Kevin Anderson is describing as potentially very dangerous. I fully agree with your conclusion that "There is still time to limit the damage using realistic solutions". We have the means to address the problem, but we don't have the political will to do what needs to be done.
50042. curiousd at 11:09 AM on 12 January 2013
       Temperatures Continue Up the Escalator
       Hi Esop in # 18 above....Could you steer me toward the Fred Singer "Unstoppable Warming Every 1500 Years" thing? I will be giving a presentation a few months from now at a place where they will probably throw that one by Singer at me as a question.
50043. curiousd at 10:26 AM on 12 January 2013
       16  ^  more years of global warming
       That is one great teaching video! BTW if you look at my post 29 in the thread "IPCC Temperature Projections Have Been Exceptionally Accurate" there is a plot of the averaged ten data sets in our SKS trend feature, but now temp anomaly plotted against log base two (conc/conc 1850). I think present thread is an appropriate place to mention that plot. Dead fit to straight line with probability no correlation abscissa and ordinate less than one in 10,000.
       Moderator Response: TC: Edited to add image.
50044. John Mason at 09:03 AM on 12 January 2013
       Met Office decadal forecasting explained: the reality
       Aircraft design relies upon computer models. Jetting off somewhere, or just feeling lucky?
50045. CBDunkerson at 08:51 AM on 12 January 2013
       Resolving Confusion Over the Met Office Statement and Continued Global Warming
       SRJ, in that case there is clearly only one 'logical' conclusion... Global warming is intermittent... and caused by volcanoes. :]
50046. Lars Karlsson at 08:07 AM on 12 January 2013
       Met Office decadal forecasting explained: the reality
       DSL, precisely. We humans use different kinds of models all the time (usually informal ones). Without models, one could neither predict the future nor understand the past. All that would remain is instinct. And although our models usually are incomplete and often wrong in one way or another, thinking with models is a lot better than not thinking at all.
50047. Kevin C at 07:10 AM on 12 January 2013
       Met Office decadal forecasting explained: the reality
       Fortunately we're not dependent on models. We've got past climate. This Knutti and Hegerl graphic from 2008 is getting dated, there's been so much work on this in the past 5 years which it doesn't cover.
50048. Kevin C at 06:50 AM on 12 January 2013
       16  ^  more years of global warming
       JoeT: Good question. The only way I've tested that is in a more recent calculation where I allow the trend post 1997 to be different to the trend pre 1997. You do get a very small difference, but it's less than 1 σ and so indistinguishable from noise. I'm not very well read on aerosol measurements, but I think Kaufmann worked his out on the basis of fuel usage. The issues is complicated by the fact that aerosols are not well mixed through the atmosphere and have different effects depending on where they are.
50049. DSL at 06:20 AM on 12 January 2013
       Met Office decadal forecasting explained: the reality
       I mean, try walking across the street without a model of how traffic moves on a street. The intuitive model will likely be accurate enough to get a person across the street without incident, though inaccuracies will occur from time to time (hopefully not fatal). Using no model . . . well, it keeps the EMTs busy anyway.
50050. Rob Honeycutt at 06:17 AM on 12 January 2013
       Met Office decadal forecasting explained: the reality
       This is speculation on my part, but I would imagine that modeling Arctic sea ice loss is an entirely different animal from surface temps. With surface temps you can at least do hindcasting to test the models. I image that hindcasting, or any other testing methods, would not be as accurate for sea ice loss, if possible at all.

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