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Comments 87451 to 87500:

87451. RyanStarr at 12:14 PM on 27 April 2011
       Muller Misinformation #1: confusing Mike's trick with hide the decline
       I asked what was a non sequitur nil point and pointed out that it was difficult getting a straight answer to straight questions from you guys. The question being do you agree with John Cook's quote. The mod snipped the whole post. He/She leaves your post unedited telling me that I act like a school teacher. Is this how we discuss science?
       Moderator Response:

       [DB] In order to be fair, comments with content in violation of the Comments Policy yet containing substantive points germane to the topic of the thread will typically have the egregious portions snipped. Repeated violations of the policy will result in the comment being deleted en toto.
       
       Per my response to you above, the criticism mentioned was of the technique, not the person utilizing the technique.  Just to be clear.
       
       I did not infer from Les' comment about teaching that there was intent to demean. Les? Want to elaborate on that point?

87452. Bob Lacatena at 11:59 AM on 27 April 2011
       CO2 effect is saturated
       149, RW1,

       This amount represents the theoretical maximum that can be emitted to space from the clear sky atmosphere, which is less than 169 W/m^2 emitted by the atmosphere depicted by the Trenberth diagram.

       Wrong. You are discounting energy from other sources (such as thermals, latent heat, energy absorbed directly from the sun, and energy transferred from clouds to the "clear sky," as you call it). The input into the "clear sky" is 78 from the sun, 17 from thermals, 80 from latent heat, an unknown fraction of 396 from the surface, and an unknown amount transferred from clouds. You cannot separate the clouds from the clear sky with that diagram. You can't figure out how much energy the "clear sky" has to emit. You can't do it, except in the single, explicit case in the diagram where outgoing LWR is separated between clouds and "clear sky." You cannot back yourself into the numbers you'd like to see. You can't do it. You can't do it. (And even if you could, it has no bearing whatsoever on the topic of the post, i.e. whether the CO₂ effect is saturated.)
87453. Bob Lacatena at 11:47 AM on 27 April 2011
       Clouds provide negative feedback
       146, RW1,

       However, the vast majority of the Earth is not snow or ice covered, which is consistent with net negative feedback for clouds, globally.

       So you say, but you offer no (substantive) support that actually proves this. You keep saying there's a net negative cloud effect, but (1) you don't prove it, and (2) as several people have pointed out, the important factor isn't the net current effect, it's the net change as a result of warming. Similarly, your logic is only so much "thought experiment" with no substantive calculations. It's easy to say things like "strong cooling effect" without backing such statements with actual numbers.
87454. muoncounter at 11:46 AM on 27 April 2011
       Cosmic ray contribution to global warming negligible
       HR#31: "an issue for any work trying to find correlations between clouds and anything, including all those papers that refute Svensmark's work." Why? If there's no correlation between GCR flux and any observable weather effect, doesn't Svensmark's hypothesis refute itself? If there's been nothing of value from the CLOUD experiment in the last 5 years, doesn't Svensmark's hypothesis refute itself? And of course, if there's no physical basis for it, doesn't it refute itself?
87455. muoncounter at 11:43 AM on 27 April 2011
       Clouds provide negative feedback
       RW1#146: "the vast majority of the Earth is not snow or ice covered, which is consistent with net negative feedback for clouds" I don't know where you live, but in my neck of the woods, nights don't get cool when there's high humidity (which is almost always) or high clouds. But here's how an actual weatherperson puts it: Clouds are regions of a high density of saturated air, (which form cloud droplets). Clouds (especially low thick clouds) have a high ability to absorb and re-emit longwave radiation. Thus, on cloudy nights much less longwave radiation is able to escape to space. Holding in heat at night is a fingerprint of the enhanced greenhouse effect. So your thesis that clouds will always be negative feedbacks doesn't hold water.
87456. HumanityRules at 11:27 AM on 27 April 2011
       Cosmic ray contribution to global warming negligible
       "There's also a possibility that the whole hypothesis rests on artifacts in cloud data." This is going to be an issue for any work trying to find correlations between clouds and anything, including all those papers that refute Svensmark's work. The sad fact is cloud data is terrible for this sort of work.
87457. RW1 at 10:44 AM on 27 April 2011
       Clouds provide negative feedback
       muoncounter (RE: 145), "Documentary evidence that cloud feedback is positive, courtesy of the good folks at the North Pole webcam site: Spring conditions can be cloudy at the North Pole. Clouds are produced when the North Pole experiences Spring warming and the beginning of Summer melting. Water is evaporated from the melting snow surface, forming the fog and low clouds that are seen in Spring/Summer pictures from the North Pole, such as the one on the right from June 2002. In the left image, from 5/1/02 19:06 UTC, the surface is covered by fog and low clouds. Radiation energy is trapped near the surface and thus the temperatures have increased to a very warm 27 F. -- emphasis added" It's not disputed that the cloud feedback is positive in areas that are permanently snow and ice covered, such as the North Pole. This is because the albedo of clouds is roughly the same as snow and ice, so the net effect of clouds is to warm by 'trapping' additional surface emitted energy. However, the vast majority of the Earth is not snow or ice covered, which is consistent with net negative feedback for clouds, globally. Also, when ice or snow melts from warming (CO2 induced or otherwise), the primary mechanisms that drive negative cloud feedback reassert themselves - specifically the latent heat of evaporation, which has a strong cooling effect on the surface, and the clouds above become more reflective than the surface, which also has a strong cooling effect.
87458. RW1 at 10:01 AM on 27 April 2011
       CO2 effect is saturated
       Sphaerica (RE: 137) "First, you can't just assume that because 1/3 of the sky is clear then that the clear sky absorbs 1/3 of the radiation." I'm not claiming the clear sky absorbs 1/3rd of the radiation. I'm saying that 1/3rd of the average surface radiation is emitted to the clear sky. This amount represents the theoretical maximum that can be emitted to space from the clear sky atmosphere, which is less than 169 W/m^2 emitted by the atmosphere depicted by the Trenberth diagram. "The ability to absorb long wave radiation is dramatically different between clear sky and clouds (clouds probably absorb substantially more, being made up of a powerful greenhouse gas, but I've never really seen any numbers on this)." I'm well aware of this. I don't see how this contradicts anything I've said. Using Trenberth's numbers, the cloudy sky absorbs 89% of the LW surface radiation emitted to it. The clear sky only absorbs 69% of the surface radiation emitted to it. "Clouds and the radiative properties of the surface are also not evenly distributed over the globe, either in space or in time. Everything else is not homogeneous." I never claimed it was. Relative to the energy balance, the averages (cloudy vs. clear sky) are what matter. "Second, you cannot ignore the non-radiative components (thermals and the release of latent heat)." I haven't. I'm well aware of them. "Third, and most importantly, you cannot ignore a major element which is not included in the diagram, which is the transfer of heat between "clear sky" and clouds. What happens when a cloud dissipates? Does the heat vanish? Is it forced to instantly radiate up to space? Does it fall to the ground with the rain?" No heat vanishes. It's either is radiated out to space, radiated down to the surface or returned to the surface in kinetic form mainly via precipitation. "Hint: When a cloud absorbs LW radiation, it is capable of transferring that heat to the surrounding and pervading atmosphere (remember, a cloud isn't a solid object, it coexists in space with the O2/N2 of the atmosphere). So it doesn't really matter which absorbs the radiation." What's your point? That the clear sky absorbs LW too? "The atmosphere (consisting of "clear sky" and clouds) absorbs the radiation, and the two cannot be separated into distinct components re this diagram." The average clear vs. cloudiness comes from the ISCCP data - not the Trenberth diagram. If, as you claim, the diagram is not depicting a 40 W/m^2 "window" through the clear sky and a 30 W/m^2 "window" through the cloudy sky with a total of 169 emitted by whole atmosphere, show me the power in = power calculations that demonstrate it. I have done so. "This diagram is not a GCM. It's just a diagram intended to help communicate the earth's energy budget to the casual viewer, and nothing more. You cannot read as much into it as you are attempting." I never claimed the diagram is a GCM. It's an energy budget diagram. With the exception of the ISCCP data on clouds, everything it taken directly from the diagram.
87459. Daniel Bailey at 10:00 AM on 27 April 2011
       CO2 Reductions Will Not Cool the Planet? We Know
       @ Don9000 Bravo, sir. You have coined a phrase: Climate Appeasement. With that in mind, let us all dwell on the words of Martin Niemöller: First they came for the Jews and I did not speak out because I was not a Jew. Then they came for the Communists and I did not speak out because I was not a Communist. Then they came for the trade unionists and I did not speak out because I was not a trade unionist. Then they came for me and there was no one left to speak out for me. Now is the time to speak out...while yet there is time to make a difference. The Yooper
87460. JMurphy at 09:59 AM on 27 April 2011
       Lindzen Illusion #1: We Should Have Seen More Warming
       That comment from Argus is a fantastic resource as a conglomerate of many so-called skeptical beliefs and complaints. It can be boiled down to sham shock, dismissal, belittling, incomprehension, misunderstanding, selective idolisation, hypocrisy, wishful-thinking, double-standards, a martyrdom-complex, naivety, and an unawareness of the absurdity of most of the claims made.
87461. Don9000 at 09:48 AM on 27 April 2011
       CO2 Reductions Will Not Cool the Planet? We Know
       Tony Abbott's statement, which I have copied below, needs to be understood from the other side's perspective: "So this is a government which is proposing to put at risk our manufacturing industry, to penalise struggling families, to make a tough situation worse for millions of households right around Australia. And for what? To make not a scrap of difference to the environment any time in the next 1000 years." Those of us who grasp that AGW is real and a serious threat easily see the flaws in this line of reasoning. The one sentence rebuttal might read something like this: "Tony, the flaw in your argument is that you fail to realize that failing to act now and going forward to reduce CO2 emissions will result in global temperature increases and climate changes that will end up costing Australian industries and struggling families much much more a generation or two down the line." This line of reasoning is second nature to many of us posting comments to this site, but it is clearly not one easily grasped by most members of the general public. For them, Abbott's statement appears to make quite good sense. As long as this holds true, we have a very perilous path ahead of us. The key flaw in Abbott's reasoning is not that he is denying global warming is happening. Instead, it is one that conservatives (in the general sense of preferring the status quo or old understanding of things rather than the new) by their nature are often guilty of: he has failed to take the additional steps in the reasoning process that are necessary to understand the need for action. Here in the U.S. I would venture to say that many opponents of taking significant action against AGW fall into Abbott's camp. A good analogy is found in the way the British government responded to Nazi aggression during the lead up to the Second World War. Over and over again, under Baldwin and Chamberlain, the British government chose to appease Hitler, rather than confront him. Appeasement had the immediate benefit of putting off the terribly unpleasant idea that much stronger action, as advocated by people like Winston Churchill, might be required. In a similar fashion, Abbott and his ilk are appeasers. Like Baldwin and Chamberlain, they are selective or biased in their use of facts, fail to follow the evidence to the logical conclusions, and yet the path they advocate offers up a far more rosy future to the populace. Whereas Baldwin and Chamberlain appeased Hitler and the Nazis, Abbott and others like him appease those of us who want to continue burning fossil fuels without any limits in the belief that doing so is not a threat. Fundamentally, as the British establishment knew full well, the alternative to appeasement in the 1930s inevitably boiled down to war. My point is that a similar situation exists today. Those of us who believe massive action is required starting right now are effectively in the position of Churchill in the lead-up to WWII. We are, in effect, calling for war. Against this, Abbott's line of reasoning is a siren call for "peace in our time" that many people find quite attractive: like Baldwin and Chamberlain, he and his ilk are betting that the consequences of their form of appeasement will either not be fully apparent till they are long gone, or will be less bad than the Churchills of our time are predicting. Our task is to convince the quavering or ignorant masses that our way is the right way forward. To do this, I think we must begin to draw attention to the craven and flawed nature of politicians like Abbott.
87462. KR at 08:41 AM on 27 April 2011
       CO2 effect is saturated
       Berényi - Also note that in sea level pressure, in the saturated CO2 bands, absorption distance is ~10 meters, not zero, and this distance increases with altitude and reduced CO2 concentration. For unsaturated wavelengths this absorption distance is much further. Given that, I don't believe a simplistic thermal conductivity measure can incorporate radiative effects. Seriously, BP - you're obviously very intelligent. But a lot of very intelligent people have been working in this field for >100 years... if you think you have (once again - I recall about a dozen of these, in UHI, OHC, etc., that did not pan out) found an issue that all the bright people have missed, you might be correct. But it's far more likely that you've missed something.
87463. logicman at 08:28 AM on 27 April 2011
       CO2 effect is saturated
       #145 - BP "It is a well known fact thermal conductivity of gases is extremely low." That is something of a cherry-pick, since it ignores the well-known effects of gases in motion. It is a well known fact that thermal conductivity of gases is extremely low, which is why gases make good thermal insulators if the possibility of convection is restricted, as in foams, wool fabrics, compressed straw, etc. It is a well known fact that thermal transfer rate of gases is extremely high if the refresh rate of air flowing over a surface is high, which is why CPUs, air-cooled engines, radiators of water-cooled engines etc. work so well at transferring heat. Fortunately, just like engineers, climate scientists know about convection and allow for it in their models.
87464. KR at 08:28 AM on 27 April 2011
       CO2 effect is saturated
       Berényi - You should, then, be aware that in English "pulled out of thin air" has extremely negative connotations with regard to numbers, namely "manufactured, made up, baseless". If you were not aware of the ramifications of that phrase, that's one thing. If you were intending it with the connotations attached, it's an accusation of data manufacture. Which is it?
87465. Berényi Péter at 07:58 AM on 27 April 2011
       CO2 effect is saturated
       #142 KR at 06:04 AM on 27 April, 2011 Again - are you retracting your accusation of manufactured data? I don't believe I'm alone in finding that deeply insulting to Trenberth et al. Listen, I have not said data were manufactured. It just came from nowhere in that paper, that's all. And this claim is true, you can verify it for yourself. "That 40 W/m² is not substantiated anywhere in the paper. It was just pulled into Fig. 1. out of thin air". Later on I have found the source in a paper written by the same author 12 years earlier, but the 2009 paper lacked any pointer to the source, window radiation is not even mentioned in the text. Also, the calculation in the 1997 paper is somewhat childish, to put it mildly. And presenting a lower bound as a best guess is misleading as well. More importantly, as the lower atmosphere is heated from below (by absorbed short wave radiation at the surface), most of it is either unstable or marginally stable. If there is excess heat at the bottom, it simply overturns the air column, possibly producing some precipitation (and releasing latent heat) as well instead of proceeding upward painfully by repeated radiation emission/absorption events. It is a well known fact thermal conductivity of gases is extremely low. When measuring this quantity, radiative and collisional heat transfer are not separated, so radiative heat transfer inside the atmosphere can't be substantial. Environmental lapse rate is 0.0065 K m^-1 while thermal conductivity of air is 0.024 W m^-1 K^-1 (that of CO₂ is even lower, 0.015 W m^-1 K^-1). It means upward heat transfer without mass exchange is about 0.16 mW/m², which is negligible. If there is a ~23 W/m² thermal flux in a substance along a 6.5×10^-3 K m^-1 temperature gradient (with no mass exchange), thermal conductivity is ~3.5 kW m^-1 K^-1, which is ridiculous. It is more than that of diamond (2.2 kW m^-1 K^-1), the best thermal conductor of all materials. In rare cases when there is a strong thermal inversion, radiative heat transfer may be somewhat larger, but still rather small compared to other fluxes (and its sign is just the opposite). If Trenberth's figures on surface radiation and back radiation are correct, physics tells us the global atmospheric window is some 50% larger than he claims.
87466. Rob Honeycutt at 07:55 AM on 27 April 2011
       Lindzen Illusion #1: We Should Have Seen More Warming
       Argus said... "In my view it is still possible that within another 25 or 50 years, those who live then will see that he was more right than wrong..." Is there any basis for this belief? If so I'd like to hear it. It's my most sincere hope that Lindzen is right, that there is a mechanism in the system that's going to produce much lower climate sensitivity than what is currently being projected. But I'm not seeing much out there to support Lindzen's position.
87467. Bob Lacatena at 07:52 AM on 27 April 2011
       CO2 effect is saturated
       141, BP, I don't quite understand your comment. I think you just have some hurried mistakes in there. Perhaps you can correct them and re-post, or clarify things:

       ...net heat transport of 23 W/m2 from surface to atmosphere by thermal IR radiation...

       The 23 I see in the diagram is reflected visible spectrum radiation. There is also 17 W/m², but that's for thermals, not "thermal IR radiation." It has nothing to do with radiated heat. Beyond this, you say:

       It means the greenhouse effect is saturated indeed.

       I don't follow you. That is, I don't follow how the proportion of energy from thermals to that escaping through the atmospheric window can have anything to do with whether or not the greenhouse effect is saturated, one way or the other. Honestly, I don't see how anyone could ever take any numbers from such a simple schematic and draw any conclusions whatsoever about the CO₂ being saturated. Can you restate your logic more clearly?
87468. Bob Lacatena at 07:45 AM on 27 April 2011
       CO2 effect is saturated
       142, KR,

       I don't believe I'm alone in finding that deeply insulting to Trenberth et al.

       Agreed. Insulting, unfounded, and pretty far over the top (as if his energy budget diagram is or was intended to be anything more than a back-of-the-envelope presentation of energy flow in the system).
87469. dana1981 at 07:24 AM on 27 April 2011
       Lindzen Illusion #1: We Should Have Seen More Warming
       Argus #89 - do you have something of substance to say about this post? "I like Lindzen therefore he must be correct" isn't exactly a very compelling argument.
87470. pbjamm at 07:16 AM on 27 April 2011
       Lindzen Illusion #1: We Should Have Seen More Warming
       Argus@89 "I guess my comment will be seriously snipped" The only insightful thing in your whole comment. I disagree though. It is more likely to be deleted altogether since it is a long winded complaint that has nothing to do with the topic. I for one cant wait to see both of our comments deleted in order to maintain some decorum on this site.
87471. Argus at 07:03 AM on 27 April 2011
       Lindzen Illusion #1: We Should Have Seen More Warming
       Professor Lindzen is the main target on this site now, I understand. The title "Lindzen Illusion #1" forebodes that we will soon see a series of articles like the Monckton Myths numbers 1 thru 16. I have stayed completely out of this site for some months, but now that I returned I stumbled on this Lindzen theme. The purpose is to prove him wrong on point after point by quoting selected reports, as if it was possible to prove anything within climate science. Climate science exists in the vast grey area somewhere in between physics and statistics. You can measure a lot of things daily or year by year, but it is still just weather when the time scale is 10, 20, or 30 years. You cannot test a climate theory in real life, on the real globe itself, unless you allow for a time scale that is too long for a human scientist. Computer models can be built to 'test' a theory, but a good model yields the desired results - those that were in fact built into the model. I have great respect for Professor Lindzen; he is still an established atmospheric physicist and a famous professor of meteorology, and he has written hundreds of publications within the subject of climate and weather. In my view it is still possible that within another 25 or 50 years, those who live then will see that he was more right than wrong (and that the IPCC was wrong about the glaciers in 2035!). On this site, however it is insinuated that he is a charlatan, a liar and a cheater. All this is of course writings by, and intended for, those that already have a certainty of belief in present-day climatology. They know they are right, and that Lindzen is completely wrong, but will any skeptic convinced by this post and these comments? Reading through all the comments to this thread, I recognize about the same 50 guys that all have the same opinions and are full of implicit faith. They have read hundreds of "reports". They are full of indignation over the fact that some professor who has slightly different opinions (a millimeter here, a tenth of a degree there) is allowed to speak in public. Then we have the 5 or so skeptics that are not so easily convinced. Without them there would be almost no discussion. They are told to go read more "reports" and come back later. If they write something considered off-topic, it is officially (-snipped-). That´s new, at least! I guess my comment will be seriously snipped.
       Response:

       [DB] Do you agree with Lindzen or not, per the topic of this post, that we should have seen more warming?  Otherwise your comment is much ado about nothing.  And thus off-topic...

87472. KR at 06:04 AM on 27 April 2011
       CO2 effect is saturated
       Berényi - You continue to use a tabulation summary as a model. I would suggest you obtain a modern copy of MODTRANS or other radiation modeling code and look at the results yourself. You should also (as Trenberth did) cross-examine satellite spectra, cloud coverage estimation on a global scale, and distribution of humidity over both ocean and land. Once you've done so, and backed up your calculations, your numbers can be taken seriously. If operating from a summary that has been adjusted for internal consistency, with considerable uncertainty on some items - not even close. Please cf. my last link in this post. Again - are you retracting your accusation of manufactured data? I don't believe I'm alone in finding that deeply insulting to Trenberth et al.
87473. Berényi Péter at 05:10 AM on 27 April 2011
       CO2 effect is saturated
       #139 KR at 02:33 AM on 27 April, 2011 Very good; looking up the references. Which, I'll note, support the value in the 2009 paper. No, it does not. It supports only a claim the value in the 2009 paper should be at least 40 W/m², but it can be larger by a wide margin. Trenberth fails to mention this detail. Does that matter? Yes, definitely. According to Trenberth there is a net heat transport of 23 W/m² from surface to atmosphere by thermal IR radiation. On the other hand if global average window radiation is more than 60 W/m², this heat transport is negligible and any net heat transport between surface and atmosphere is mediated by thermals and evaporation. That's a big difference. It means the greenhouse effect is saturated indeed. Surface and atmosphere is in radiative equilibrium (as it should) except for the fraction of radiation that escapes directly to space. For example if effective temperature of the surface is 289 K (16 °C), effective temperature of the atmosphere as seen from the surface is 277 K (4 °C) and window radiation is 62 W/m², the above relation holds. Value of net heat transport by radiation between surface and atmosphere has enormous physical consequences, so you can't miss it by 10's of watts and still claim the physics is understood.
       Response:

       [DB] Again, please substantiate, or withdraw, your allegation of manufactured data made against Dr. Trenberth.

87474. johnd at 04:43 AM on 27 April 2011
       Extreme weather isn't caused by global warming
       michael sweet at 16:53 PM, by what measure have you ascertained that current changes are greater than those that occurred during the period being discussed? From 700 to about 1100 AD the region experienced population increases ascribed to to reliable and above average precipitation. This then changed over a very short period into what is described as the 300 year Great Drought. Given the other civilisations that apparently collapsed at about the same time, both in North and South America, also apparently due primarily to changes in precipitation patterns, perhaps the changes were more widespread. Whilst it seems a common feature of many of those earlier societies to believe their Gods were responsible for bringing the rains, hence the rituals and sacrifices, modern day understanding is of how it is the pattern of SST's that primarily determine precipitation patterns, with land use changes and deforestation further influencing regional climates. It is then not surprising that a number of different early civilisations subject to the changing conditions of the same ocean basins would have experienced similar climatic changes related to shifts in SST's and hence precipitation patterns. Interestingly, one of the more long lasting civilisations, the Mayans, developed and built complex systems of water management which perhaps are indicators of both their ongoing need to manage a vital but variable resource, and that success in doing so is necessary to ensure a society not only prospers, but survives.
87475. muoncounter at 04:26 AM on 27 April 2011
       Clouds provide negative feedback
       Documentary evidence that cloud feedback is positive, courtesy of the good folks at the North Pole webcam site: Spring conditions can be cloudy at the North Pole. Clouds are produced when the North Pole experiences Spring warming and the beginning of Summer melting. Water is evaporated from the melting snow surface, forming the fog and low clouds that are seen in Spring/Summer pictures from the North Pole, such as the one on the right from June 2002. In the left image, from 5/1/02 19:06 UTC, the surface is covered by fog and low clouds. Radiation energy is trapped near the surface and thus the temperatures have increased to a very warm 27 F. -- emphasis added [source] Temperature inset at lower left shows 27F as stated.
87476. CBDunkerson at 04:06 AM on 27 April 2011
       Models are unreliable
       trunkmonkey writes: "Any computer model that predicts temperature as whatever convoluted function of CO2 will always be right because they ALWAYS correlate." Excellent. By this statement we would have to conclude that the current rise in CO2 must result in a correlating rise in temperature. Glad to see you are coming around.
87477. Ari Jokimäki at 03:26 AM on 27 April 2011
       Cosmic ray contribution to global warming negligible
       HumanityRules #26: Couple of quotes from Erlykin et al. conclusion section: "Concerning the troposphere,it seems that there is a finite influence of CR on cloud cover at the level of f ~ 1%, a result that is mainly for clouds below about 6.5km, although when averaged over the entire atmosphere it is smaller than this." "Disregarding the latter fact and taking an average f value of 1%, the temperature change consequent upon the changing CC given by the maximum CR change that could be allowed over the last 50 years can be calculated. Over this period the mean CR intensity appears to have fallen by less than 0.6%, using the data of Bazilevskaya et al.,(2008), so that if the conversion, ΔCR to ΔCC and there by to ΔT is known, ΔT can be calculated. Here, we adopt the conversion ΔCC = 11.3% corresponds to ΔT = 0.5°C from the work of Erlykin and Wolfendale(2010). The increase in temperature predicted is 0.002°C,..." By the way, as far as I have seen, very few of the papers that cite Svensmark's old works give support to the hypothesis. Most are neutral (just mention that there is this hypothesis) and many of them are against the hypothesis and show errors in his work. Here are few papers citing his work and showing that he is wrong. There's also a possibility that the whole hypothesis rests on artifacts in cloud data.
87478. Bob Lacatena at 03:02 AM on 27 April 2011
       CO2 effect is saturated
       RE my comment in 137, I inappropriately said "clouds probably absorb substantially more." I should probably withdraw that assumption upon the realization that while clouds cover on average of 2/3 of the surface, they make up considerably less of the total volume of the troposphere (7%, Lelieveld et al., 1989; Pruppacher and Jaenicke, 1995). This means the atmosphere has opportunities to absorb that same radiation before it reaches the clouds (in the lower, denser part of the atmosphere where there is substantially more CO₂ and water vapor), as well as above the clouds. Comparing the outgoing LW radiation by latitude and season versus the cloud distributions by latitude and season demonstrates an even greater imbalance that must be addressed. Obviously, things are a lot more complex, and such a brash, broad assumption was unwarranted. Apologies for the error.
87479. trunkmonkey at 02:43 AM on 27 April 2011
       Models are unreliable
       I just found the NASA publication (Oct 2010)that I think may be the basis for the link at the top of this site about CO2 being the most important control knob. (This link did not work for me) Wow! The GISS model predicts that if all the CO2 in the atmosphere were neutralized GAT would drop to the level of Wisconsin glaciation in the first year! And would drop to levels capable of producing sea ice near the equator in a decade! As a paleo guy I had to put my feet up and think about this one. On one hand the result is utterly absurd and a clear indication that the model parameterizes far too many magical properties to CO2. On the other hand we actually need a mechanism to explain why climate is so bloody unstable. The forams are telling us that even during the prevuously supposed halcyon periods like the Mesozoic the were wild swings in temperature. The F-15 is an airplane whose "forcings" are so strong that no human has the reaction time necessary to fly it and computers are required to smoothe. Perhaps we have an F-15 climate? Water is a likely candidate for the wild thing with two phase transitions within earth temperature range and attendant latent heat as well as "feeds" back, forth, up, down and sideways. Whether CO2 is the moderating agent is debatable. A serious model of earth climate has to account for three things that vary in both duration and amplitude: On a millenial time scale the DO ocillations. On a million year scale the glacial-interglacial episodes within glacial periods. On a billion year scale the glacial periods themselves with 200 million year intervals of higher temperatures. No model even approaches this standard and ( -invective snipped- ). We know that temperature and CO2 have tracked together like mutt and jeff for 800,000 years. The computer models are hypotheses that CO2 has controlled temperature. I am going to ( -invective snipped- ) by advancing a hypothesis that at least until our own efforts may have decoupled them that over all of the Phanerozoic temperature has controlled CO2. What data have we to contradict this? After all, it is what the ice cores have been trying to tell us if we could only break the chains of our preconceptions. Any computer model that predicts temperature as whatever convoluted function of CO2 will always be right because they ALWAYS correlate.
       Response:

       [DB] Please stick to the science and reduce the level of invective.

       CO₂ Control Knob links:

       1. Richard Alley (Video Presentation) 2009
       2. Lacis et al 2010
87480. KR at 02:33 AM on 27 April 2011
       CO2 effect is saturated
       Berényi - Very good; looking up the references. Which, I'll note, support the value in the 2009 paper. Does this mean you are withdrawing your accusation of manufactured data? There are a lot of uncertainties in the numbers Trenberth presents, as is clearly discussed in the article: amounts of convective activity, latent heat numbers from precipitation, large scale estimation of the surface radiance covering sufficient points to cover variation, etc. Others are much more certain: backradiation, insolation, and so on. Taken together, they add up to 10's of watts. Does that matter? No. Trenberth's energy budget is not a GCM, not predictive, but rather an overview of the data available adjusted for internal consistency. Running off and arguing about differences within the range of error of individual element uncertainties is not productive. Such decimal point gaming certainly has no traction in proving/disproving any element of the radiative greenhouse effect. I'll note that this discussion is rather off topic - unless, as you seem to be arguing, that you are attempting to find more evidence for the fact that the CO2 effect is indeed not saturated.
87481. Berényi Péter at 02:13 AM on 27 April 2011
       CO2 effect is saturated
       #136 KR at 22:44 PM on 26 April, 2011 Trenberth may have thought that it wasn't necessary to to spend much time on a value that has been known for >80 years. A value you could have determined with a few moments of web search, I'll note. Really? I thought the proper way to determine values of physical quantities is to measure them. On the other hand Trenberth simply assumes it is 40 W/m². We can get a deeper insight into his thought process if we consider an old paper of his where the problem is elaborated on briefly. Bulletin of the American Meteorological Society, 1997 Earth's Annual Global Mean Energy Budget J. T. Kiehl & Kevin E. Trenberth "Some of the radiation leaving the atmosphere originates near the earth's surface and is transmitted relatively unimpeded through the atmosphere; this is the radiation from areas where is no cloud and that is present in the part of the spectrum known as the atmospheric window, taken here to be the wavelengths 8-12 µm (Fig. 7). The estimate of the amount leaving via the atmospheric window is somewhat ad hoc. In the clear sky case, the radiation in the window amounts to 99 W m^-2 , while in the cloudy case the amount decreases to 80 W m^-2, showing that there is considerable absorption and re-emission at wavelengths in the so-called window by clouds. The value assigned in Fig. 7 of 40 W m^-2 is simply 38% of the clear sky case, corresponding to the observed cloudiness of about 62%. This emphasizes that very little radiation is actually transmitted directly to space as though the atmosphere were transparent". Taken here to be & somewhat ad hoc, indeed. A value of 40 W/m² would imply a broadband thermal infrared optical depth of 2.29 (which roughly means the average photon gets absorbed 2.29 times before it escapes to space). On the other hand this value averaged over the entire surface is below 1.9, that is, total thermal radiation flux escaping from surface to space unimpeded is above 60 W/m². Trenberth's simple calculation makes two omissions. One is the polar window (above wavelength 16 μm), covered only by weak water vapor absorption lines, so in extremely dry regions (like polar ones) a considerable amount of radiation can get through in that frequency band. The other one is clouds. As clouds are always fractal structures, cloud covered surface has a fractal dimension less than 2 (and decreasing poleward). Cloud fraction is usually determined by counting cloudy vs. clear sky grid cells (pixels). However, the finer the grid resolution is, the less the ratio of cloudy pixels will be, because fractals are just like that. It means even in areas categorized as "cloudy" some thermal IR can get through to space unimpeded. Therefore thermal IR radiation flux originating near the earth's surface and transmitted relatively unimpeded through the atmosphere is measured to be more than 40 W/m², Trenberth's back-of-the-envelope calculation is only good as a lower bound. An error on the order of ~20 W/m² in one of the components is a serious one if an average planetary imbalance of less than 1 W/m² is pursued.
87482. muoncounter at 02:05 AM on 27 April 2011
       Cosmic ray contribution to global warming negligible
       HR#27: "Common sense says the debate is still alive. " Here are Laken et al 2010: These results provide the most compelling evidence presented thus far of a GCR-climate relationship. From this analysis we conclude: (i) a GCR-climate relationship is governed by both the rate of GCR flux and internal precursor conditions; and (ii) it is likely that this natural forcing has not contributed significantly to recent anthropogenic temperature rises. --emphasis added The debate may be 'alive,' but the conclusion seems clear cut.
87483. Philippe Chantreau at 01:44 AM on 27 April 2011
       Cosmic ray contribution to global warming negligible
       Common sense says that there is not that much of a debate if there is no physical mechanism. There is none so far by which cosmic rays can directly influence cloud formation, because it has not been shown that any kind of CCN can actually be generated by CRs. On the other hand, CO2's radiative properties are well understood, so is their physical mechanism, with empirical measurements that agree with the theoretical calculations. It does not prevent "skeptics" to apply all sorts of doubts, even some that indicate complete diregard or lack of understanding of physics. Cloud formation is subject to the kind of variables that "skeptics" take as an excuse all the time to claim that nothing can be asserted with any level of certainty. The lack of physical mechanism prevents any kind of theoretical prediction. The correlation claimed by Svensmark has been examined and not reproduced by other teams. Common sense says there is even less debate there than meets the eye. Papers published that did not confirm Svensmark's hypothesis will cite him as well. I'm not so sure that 462 citations in 14 years is that remarkable. Common sense dictates to go to the physics. If there isn't any for particle growth, this hypothesis should be given low consideration.
87484. damorbel at 00:43 AM on 27 April 2011
       2nd law of thermodynamics contradicts greenhouse theory
       Re #1015 Fred Staples you wrote:- "The theory suggests that doubling the CO2 in the atmosphere moves the boundary between the optically thick region below, and the optically thin region above, where radiation to space is relatively unimpeded. Since this region is colder, outgoing radiation falls, and the sun warms the entire system, shifting the lapse rate to the right." This hypothesis has many weaknesses. One of Tyndall's most important discoveries was that GHGs were the perfect absorbers of their own emissions. This has the important consequence that, if two samples are irradiating each other, heat energy only goes to the cooler from the hotter, (tending to raise it temperature) thoroughly in accord with the 2nd law. The same is true for density, the denser emits more radiation than the less dense, assuming the two samples have the same temperature. Of course in the atmosphere both effects (density and temperature difference) are to be observed, so there is considerable energy transfer, but only upwards. Without energy transfer 'downwards' there will be no heating of the surface by adding GHGs.
       Moderator Response: [muoncounter] This is not a forum for endless repetition of your prior comments (see #143 on this thread and its rebuttal here). If you can only recycle your prior words, perhaps you really have nothing further to contribute.
87485. HumanityRules at 23:39 PM on 26 April 2011
       Cosmic ray contribution to global warming negligible
       3 arch stanton I really should have directed you to his 1997 paper "Variation of cosmic ray flux and global cloud coverage - A missing link in solar-climate relationships" which has 462 references on Web of Science and is still being actively referenced this year. I'm not sure it makes any sense to think the peer-review process would allow "this guy is wrong" to be published 462 times, or that Svensmark would be still getting grants or publishing on this work if that was the case. Common sense says the debate is still alive.
87486. HumanityRules at 23:31 PM on 26 April 2011
       Cosmic ray contribution to global warming negligible
       Ari you wrote "This distribution of correlation results a possible effect to global cloud cover which is smaller than 1%." and "Assuming 1% effect of the cosmic rays to cloud cover, this would cause a warming of 0.002°C in global surface temperature." Can you just confirm what you meant here? My reading is CGR may have been responsible for ~1% change in cloud cover. And this 1% change causes 0.002oC rise in temperature? That doesn't sound right, a 1% change in clouds seems like a lot and would have a significant affect on albedo. Are you sure you got your numbers correct (I can't access the paper unfortunately). This abstract from a presentation by the authors in 2010 suggests a 0.2% CGR flux in the past 50years and a 0.01% change in clouds.
       Moderator Response: [DB] Fixed missing URL.
87487. Bob Lacatena at 23:28 PM on 26 April 2011
       CO2 effect is saturated
       131, RW1,

       which means 1/3rd of the surface is clear sky. 396 W/m^2 x 0.33 = 131 W/m^2 emitted from the surface to the clear sky.

       I won't get into Trenberth's diagram with you again (entirely). I'll repeat that you don't understand it, you are making invalid assumptions, you don't understand enough of the underlying physics of atmospheric heat transfer, and this is all leading to gross misinterpretations. However, concerning this particular statement of yours about "1/3rd ... clear sky"... First, you can't just assume that because 1/3 of the sky is clear then that the clear sky absorbs 1/3 of the radiation. The ability to absorb long wave radiation is dramatically different between clear sky and clouds (clouds probably absorb substantially more, being made up of a powerful greenhouse gas, but I've never really seen any numbers on this). Clouds and the radiative properties of the surface are also not evenly distributed over the globe, either in space or in time. Everything else is not homogeneous. Second, you cannot ignore the non-radiative components (thermals and the release of latent heat). Third, and most importantly, you cannot ignore a major element which is not included in the diagram, which is the transfer of heat between "clear sky" and clouds. What happens when a cloud dissipates? Does the heat vanish? Is it forced to instantly radiate up to space? Does it fall to the ground with the rain? Hint: When a cloud absorbs LW radiation, it is capable of transferring that heat to the surrounding and pervading atmosphere (remember, a cloud isn't a solid object, it coexists in space with the O₂/N₂ of the atmosphere). So it doesn't really matter which absorbs the radiation. The atmosphere (consisting of "clear sky" and clouds) absorbs the radiation, and the two cannot be separated into distinct components re this diagram. This diagram is not a GCM. It's just a diagram intended to help communicate the earth's energy budget to the casual viewer, and nothing more. You cannot read as much into it as you are attempting. So, again: 1) You need to study more before you can comment on or interpret Trenberth's diagram. 2) Trenberth's diagram is not the topic of this thread. [This will be my last post on the subject (here), so please don't come back with an angry list of "but what about this?" questions. I'm not biting.]
87488. HumanityRules at 22:56 PM on 26 April 2011
       Cosmic ray contribution to global warming negligible
       3 arch stanton I just checked Web of Science and there are 167 papers referencing Svenmark's early 2000 paper. I haven't checked all of them and I'm guessing you haven't but if "Little in the scientific literature supported it then and even less does now." was true then almost all would have to have come down against Svenmark's work. If that was true it would be fair to say we wouldn't still have a debate in the science. Just a quick check at 2010 papers finds this paper. The scientific debate seems to be more alive than you present it.
87489. KR at 22:44 PM on 26 April 2011
       CO2 effect is saturated
       Berényi - The infrared atmospheric window was derived in 1918 from the H2O spectra, first estimated (by hand) in 1928. Now the value of transmitted energy is determined as a side product of the line-by-line radiation models, to distinguish between surface radiation actually transmitting directly to space and atmospheric radiation on the edges of the window also radiating to space. Trenberth may have thought that it wasn't necessary to to spend much time on a value that has been known for >80 years. A value you could have determined with a few moments of web search, I'll note. In my opinion, your language here is skating the thin edges of the Comments Policy regarding accusations of deception.
       Response:

       [DB] Sometimes, in the course of human events, it's necessary to reinvent the wheel.

       As you note, the fact that some then find it necessary to reinvent the flat tire is revealing.

87490. Fred Staples at 22:41 PM on 26 April 2011
       2nd law of thermodynamics contradicts greenhouse theory
       In order to discuss the “higher is colder” theory, which most contributors to this thread endorse as the only plausible explanation of AGW, we have to leave the comfortable certainties of thermodynamics, (and G and T) and move on to the more controversial arguments of climate science. A good debate on the basic Physics can be found at “Climateclash.com”, which includes the basic spectroscopy as well as “higher is colder”, presented in a long paper by Ray Pierrehumbert (Infrared radiation and planetary temperature) and numerous posts from Leonard Weinstein. The theory suggests that doubling the CO2 in the atmosphere moves the boundary between the optically thick region below, and the optically thin region above, where radiation to space is relatively unimpeded. Since this region is colder, outgoing radiation falls, and the sun warms the entire system, shifting the lapse rate to the right. To some extent this must be true, but it is reasonable to ask if effect is detectable. It is almost never quantified (an obscure calculation at P 113 of Taylor gives an elevation of 3kms, and a temperature increase of 18 degrees C). With a lapse rate of 6.5 degrees C per 1000 meters, we are looking for an elevation of the effective radiation level of just 154 meters for an increase in temperature everywhere of 1 degree C. Since the transition from thick to thin must be gradual, and different for different frequencies of radiation, there is no possibility of detecting such a change directly. Then there is the role of water vapour. At sea level, the H2O concentration about 12000 ppm, or more than 30 times CO2. Over the troposphere as a whole it is 20 times CO2, and at 5 kms (the region of effective radiation) it is still 4 times greater. Doubling CO2 to 600 ppm will still leave H2O as the dominant greenhouse gas. Thereafter, it falls away rapidly, to create the optically thin region, but it is will still mask the effect of any increase in CO2 absorption at the effective emission point. The only mechanism by which doubling the CO2 concentration can elevate the emission level is absorption, with atmospheric warming (via kinetic energy) and subsequent emission (and consequential cooling). To measure that effect we would expect to find experiments. The usual suspects (Woods and Angstrom) are a century old, and hotly disputed (usually without the tedium of repetition). One experiment reported on the net is at espere.net/united kingdom/water/uk_overview.htm. It is an attempt to demonstrate the greenhouse effect, they pass short wave radiation through gas-filled containers, with long wave radiation filtered out. Back-warming of the gasses is from black cardboard (which absorbed the incoming radiation)in the base of the containers. They compare air (at atmospheric pressure) with 100% CO2, a greater concentration than on Venus. Anyone expecting a dramatic difference will be disappointed. Initially, the CO2 warms rather faster. After 5 minutes the increases are : 100% Co2 15 degrees C Air 10 degrees C In the next 15 minutes additional warming was as follows: 100% Co2 13 degrees C Air 12 degrees C Sadly, the experiment stopped (before equilibrium) just when it was becoming interesting. For those with long lives ahead, the earth’s AGW experiment will go on long enough to resolve doubts and errors, and reach a conclusion.
87491. Bernard J. at 22:40 PM on 26 April 2011
       Lindzen Illusion #1: We Should Have Seen More Warming
       Chris G at #69 and LazyTeenager at #87. 'H Pierce' appears to be one Harold Pierce Jnr, a recalcitrant, statistically-inept AGW denialist who has a long track record at Deltoid of inappropriate use of statistical tests. For example, HPJ used many dozens (at least) of t-tests to compare various weather station temperatures over time, even after the issue of repeated measures was pointed out to him. Further, I suspect that I have previously pointed out to HPJ the very fact of the accuracy of averages of large datasets being greater than the accuracy of any random individual datapoint in the set. Cherry picking and misrepresentation, such as demonstrated by Lindzen in the top of this thread, are prime devices for denying the existence of climate change. Deliberate and incompetent misuses of statistics and analysis are some of the favoured tools to achieve this denial, as tens of thousands of denialist comments on hundreds of blogs and in hundreds of newspapers will attest. Sadly, it is unlikely that objective science can ever really decapitate this beast of ignorance. In this regard, I feel Sphaerica's pain at #62. Perhaps one partial solution would be to have a list of basic statistical rebuttals here similar to the ever-growing list of conceptual rebuttals on Skeptical Science - then all one would need to do is to provide a link, and leave alone the painful repetition of basic explanations that have been covered many times previously.
87492. JMurphy at 19:17 PM on 26 April 2011
       A Convention for Persons Displaced by Climate Change
       I have added a comment on the Texas situation on the Extreme Weather thread.
87493. JMurphy at 19:16 PM on 26 April 2011
       Extreme weather isn't caused by global warming
       This report provides further information to a discussion going on over on the A Convention for Persons Displaced by Climate Change thread : Interior Releases Report Highlighting Impacts of Climate Change to Western Water Resources. Specific projections include: •a temperature increase of 5-7 degrees Fahrenheit; •a precipitation increase over the northwestern and north-central portions of the western United States and a decrease over the southwestern and south-central areas; •a decrease for almost all of the April 1st snowpack, a standard benchmark measurement used to project river basin runoff; and •an 8 to 20 percent decrease in average annual stream flow in several river basins, including the Colorado, the Rio Grande, and the San Joaquin. Report available here : Reclamation : Managing water in the West
87494. Berényi Péter at 19:14 PM on 26 April 2011
       CO2 effect is saturated
       #130 Tom Curtis at 11:21 AM on 26 April, 2011 Trenberth 09 shows a 40 Watt/m^2 atmospheric window That 40 W/m² is not substantiated anywhere in the paper. It was just pulled into Fig. 1. out of thin air.
       Response:

       [DB] "It was just pulled into Fig. 1. out of thin air."

       Please substantiate, or withdraw, this allegation.

87495. RSVP at 19:04 PM on 26 April 2011
       Waste heat vs greenhouse warming
       KR #398 "there's no effect on climate until it ("buried energy") surfaces" I can only assume you deny the effects of convective heat transfer because your models do not include them. Likewise, if you deny the existence of heat conduction in materials, in preference to science fiction, I suppose we are speaking in different languages.
87496. Forced Migration Review at 18:53 PM on 26 April 2011
       A Convention for Persons Displaced by Climate Change
       Coming to this late. You might be interested in articles in Oct 2008 issue of Forced Migration Review focusing on climate change. For example, 'The numbers game' by Oli Brown - online at OliBrown-article Full pdf and contents listing online at FMR31-climate-change best wishes Marion (co-editor, Forced Migration Review)
87497. damorbel at 18:09 PM on 26 April 2011
       2nd law of thermodynamics contradicts greenhouse theory
       Re #1012 Tom Curtis you wrote:- "Consequently if you are not explicitly discussing 2nd law issues, may I suggest you take your discussion elsewhere." The argument I put is that adding gases that radiate (and absorb) are to the mixture comprising the atmosphere in the zone known as the troposphere, cannot change the equilibrium temperature of the surface because this region is almost always colder than the surface. The argument is based on the 2nd Law of thermodynamics which is that energy transfer (which is required for temperature change) cannot result in an increase (i.e. net increase) of the surface energy which would be required for a rise in surface temperature, because the temperature of the troposphere is, in general, lower than the surface. This fact is known because with a few exceptions known as inversions, the gradient of temperature against altitude is negative, meaning that the troposphere is almost always colder than the surface. It may be thought relevant why the Troposphere is always colder than the surface, I suggest this is a relevant matter.
87498. michael sweet at 16:53 PM on 26 April 2011
       Extreme weather isn't caused by global warming
       Johnd, The climate changes caused the Anasazi civilization to collapse. Is that what you want to happen to our civilization? Jahred Diamond used this as one of the examples in his book Collapse about how previous civilizations found changes in their environment too much to survive. Current changes are greater than the Anasazi had to deal with.
87499. Ken Lambert at 14:14 PM on 26 April 2011
       A Flanner in the Works for Snow and Ice
       Daniel Bailey #130 Quite a bard Daniel. We can do science in rhyming couplets if you like - the numbers will still end up the same. I have already calculated the heat gain from the loss of sea ice mass at #66. Using the trend off the PIOMAS chart of -3.5E3 km3/decade, the number comes to 1.17E20 Joules/year. I used 1000kG/m3 for the density of ice, and Tom Curtis 'corrected' my hasty calc by pointing out that the density of Sea Ice is 917 kG/m3. Tom helpfully said: "You forgot to compensate for the lower density of ice, which is 917 kg/m^3 which reduces your figure to 1.07*10^20 Joules per year" Since this reduces my number by a massive 9% to be closer to Dr Trenberth's number of 0.9E20 Joules/year, his pedantry just does not transpose to his own calculations which at various times have be out by factors of 15 times, 2 times (was it 149 times way back in the beginning?)etc etc. Such bizarrity has even extended to Tom quoting temperatures to about 8 places behind the decimal point, for what purpose I cannot fathom. Even if we accept Flanner's number for NET Arctic sea ice melt due to reduced albedo of the missing sea ice, the number is still 5/145ths or 3.45% of the Earth's net imbalance from the Arctic - 4.4% of the planet's surface area. At the beginning of this thread - the theme was the supersized contribution of the Arctic to global warming. Anyway Daniel - what is your point?
87500. adelady at 13:33 PM on 26 April 2011
       A Flanner in the Works for Snow and Ice
       db, I think I'd re-do that graphic without the links from year to year. Just a couple of simple dotted lines. One across at 8000 cubic km, one vertically at 4 million sqkm. Doesn't matter what we think about comparing trends, years, decades. We really are in new territory.
       Moderator Response: [DB] Thanks for the suggestion; that one was not mine, though. The looming Zero point on the graph is compelling in itself. "We really are in new territory." Sadly, yes. And it happens on our watch.

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