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CBDunkerson at 02:01 AM on 23 April 2011Lindzen Illusion #1: We Should Have Seen More Warming
Ron, I have to wonder whether 'freedom of speech' should include 'freedom to lie' in this way. After all, the classic example of the limit of freedom of speech is, 'yelling FIRE in a crowded theater which is not actually on fire'. So there is already a concept that untruthful speech is not allowed when it creates a danger. Likewise, we prevent advertisers from making false statements about their products. Frankly, I'm surprised that false statements about global warming haven't ended up in court yet. There has clearly been false testimony to Congress... which is illegal. There have clearly been cases of defamation against Michael Mann and others. The public statements of many AGW deniers have been both untrue and dangerous. Sooner or later the matter will have to end up in the courtroom... and for all the flaws of modern justice they do at least still require that evidence be true... at which point AGW deniers don't have a leg to stand upon. -
Berényi Péter at 01:53 AM on 23 April 2011Clouds provide negative feedback
#92 Sphaerica at 21:57 PM on 21 April, 2011 I'd suggest that of that 341, since 78 is absorbed by the atmosphere, only 263 is available to be reflected (although this is a gross estimate, since it's more complex than that). If one assumes a cloud cover of .66 then 174 of that 263 is subject to cloud cover. 79 reflected from 174 gives .45, which is well within the ranges given by Hansen 1998 -- even at the upper end. No, that's not correct. Trenberth's figure clearly shows that according to him from the average 341 W/m2 incoming shortwave solar radiation at ToA 78 W/m2 is "Absorbed by Atmosphere" and 79 W/m2 is "Reflected by Clouds and Atmosphere" (right back to space, yes). Therefore a fraction of that 79 W/m2 is reflected by the atmosphere, not clouds, so somewhat less than 79 W/m2 remains to be reflected by global cloud cover. If cloud fraction is 0.66 as you say and no short wave radiation is reflected by the atmosphere from cloud free regions, then average cloud albedo is 79/341/0.66 (=0.35) which is way too small (should be more than 0.42). On the other hand if there is some reflection from the atmosphere in cloud free regions, average cloud albedo comes out even smaller.
It may be the case that average cloud fraction projected to a plane perpendicular to incoming solar rays is much smaller than 0.66. It should be close to 0.5 to bring cloud albedo back to a reasonable range. It would simply mean cloud fraction around polar regions is much higher than the global average while it is lower above the rest of the globe. I do not know if it is the case or not, I have not seen data on average latitudinal distribution of cloud cover. If anyone knows a link to such measurements, that could help a lot.
However, if cloud fraction is so high in polar regions indeed, it would diminish ice-albedo feedback tremendously, because, unlike in glacial times, there is not much ice to be melted elsewhere.
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Ron Crouch at 01:42 AM on 23 April 2011Lindzen Illusion #1: We Should Have Seen More Warming
The misrepresentations to the public in general by Lindzen and others doesn't really concern me that much (that freedom of speech thing). After all are we not pummelled on a daily basis with misrepresentations as we conduct our lives? It's up to each individual to wade through the relentless inputs on a daily basis and sort out the garbage from the truth. Unfortunately few have the luxury to ponder detail and thus are easily swayed. A certain person proved this to be the case in January 1933 (oh how history repeats). What should be of concern is the testimony before such bodies as Congress, and what, if any, analysis of that testimony is taken into consideration by policy makers. -
Chris G at 01:40 AM on 23 April 2011A Convention for Persons Displaced by Climate Change
Many thanks to Albatross, Dan Olner, and Adelady for their information and perspectives. Thoughts: Honestly, if the nations of the world have done so little to address the cause of the problem, I have little hope that they will be willing to proactively invest in mitigating solutions to the problem. Climate refugees will always be difficult to get an exact count on. It's like cancer and smoking, you can't really say with high confidence that any individual contracted cancer because of smoking, but you can say with high confidence that the incidence of cancer is higher amongst smokers. Is it just my eyes, or is there a reasonable association with areas labeled as being at risk for droughts in the 2005 map above and the droughts that have recently occurred in Russia, Texas, and narrowly avoided in China? -
Albatross at 01:20 AM on 23 April 2011Lindzen Illusion #1: We Should Have Seen More Warming
Arkadiusz @21, I'm sorry, but am not sure whether you posted that to critique or support Lindzn's obfuscation. -
muoncounter at 01:20 AM on 23 April 2011Video on why record-breaking snow doesn't mean global warming has stopped
Interesting recent letter in Nature: Kaspi and Schneider 2011 Winter cold of eastern continental boundaries induced by warm ocean waters we show that this anomalous winter cold can result in part from westward radiation of large-scale atmospheric waves—nearly stationary Rossby waves—generated by heating of the atmosphere over warm ocean waters. ... Our results show that warm ocean waters contribute to the contrast in mid-latitude winter temperatures between eastern and western continental boundaries not only by warming western boundaries, but also by cooling eastern boundaries. Figure below: Surface temperature deviation averaged over northern hemisphere winter months and across 40 years. Credit Tapio Schneider Yohai Kaspi
-- source
A standing wave pattern with a wavelength the distance from Seattle to London?
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khayhoe at 01:19 AM on 23 April 2011Skeptical Science in other media
I appreciate the discussion here. Nicholas's statistics are very much in line with my own experience. Moreover, those who believe that the seriousness of global warming has been exaggerated are generally one and the same as those who believe in a young earth. Here is the difference, though, in my mind: Climate change is an urgent problem. It is already seriously affecting our planet and our own health and welfare. If we continue to deny the reality of the problem and don't do something about it within a relatively short period of time, we will be facing some very dangerous consequences of our actions. On the other hand, we (by which I mean any one of us here on planet earth) can happily and safely believe in a young earth for a very long time without this belief having any direct global repercussions. (I understand there are indirect ones regarding our perspective on science--but not in the same ballpark as the very real effects of climate change already manifesting themselves today) So in reaching out to my faith community, I think it is very important to differentiate between these points. On the second one, we can afford to wait. On the first, we cannot. -
funglestrumpet at 00:53 AM on 23 April 2011Lindzen Illusion #1: We Should Have Seen More Warming
Stephen Bains @15 "I don't see any mechanism that would be relevant really, given Lindzen has such a willing audience outside of academia. He has already lost his credibility on this issue in the academic community. What difference does it make?" 1 If no mechanism, create one. 2 The difference it would make is that any public 'striking off' that would result would curtail his appearance before willing audiencies and restrict his being quoted by those politicians with a hidden agenda. If, as you say, Lindzen is discredited within the academic community, yet is called upon to give talks to radio shows and evidence before congressional committees, then something is wrong, very wrong. On any issue, such a thing would be bad, but on one as serious as climate change has the potential to be, it borders on criminal behaviour. Clearly, Lindzen, Christy and suchlike would be wary of behaving the way they do if at risk of being subject to a meaningful sanction. The question that springs to my mind is why is the scientific community so blasé about something that brings all of them into disrepute in the eyes of the general public? The average person on the street has no idea that Lindzen is not to be trusted. All they see is two sides of a difficult (in their eyes) argument going hammer and tongs at each other. The action needed to combat climate change is dramatic and getting more so as time passes. Why on earth would anyone support such measures when as far as they can see there is very real doubt regarding the need? As a relative outsider, it seems to me that the longer the world holds back from making the changes needed, the more it can be said that the IPCC, and the rest of scientific community that agrees with it, is winning all the battles, but slowly losing the war. There needs to be a climate (no pun intended) where people that go beyond the realm of legitimate differences of opinion - and I believe that that is what is under discussion here - are compelled to change their ways or suffer serious consequencies. What those should be and how to administer them is up the scientific community to decide. That is never going to happen if there is no discussion on the matter. All I am trying to do is sow the seeds that may lead to one. I am not qualified to do more and if the issue were not so serious, wouldn't ever bother to do this much. -
Alteredstory at 00:42 AM on 23 April 2011Mars is warming
Something that just came out, and may have an impact: http://www.sciencedaily.com/releases/2011/04/110421190450.htm Large dry ice deposits in Mars's South pole, that look as if they are currently in a dispersal phase - sublimating into the atmosphere as CO2.Moderator Response: [Dikran Marsupial] Activated link -
Ron Crouch at 00:27 AM on 23 April 2011Clouds provide negative feedback
113, RW1, From the ISCCP data, which says that clouds cover 2/3rds of the surface. This means 1/3rd of the surface is clear sky (i.e. cloudless). What about cloud pressure? What about optical thickness? What about cloud albedo? How much is low cloud? How much is high cloud? What is the moisture content in the air column? What are the particulate concentrations in the air column? And there's more. Not quite so black and white is it? -
The Skeptical Chymist at 23:59 PM on 22 April 2011Lindzen Illusion #1: We Should Have Seen More Warming
Arkadiusz @ 21, I read your post and I don't find it convincing. You don't provide any evidence Linzden is correct and most of what you say doesn't even refer to transient climate sensitivity (the subject of this post). One thing though, you quotes from Linzden appear to have him claiming that if there is a discrepancy between the surface temperature data / climate models and the satellite data, then the satellite data will be correct. A little history shows we have been here before and it was the satellite data that was shown to be wrong. Considering how much more difficult it is to get accurate temperature data out of a satellite (or radiosondes for that matter) compared to a ground based thermometers I'm skeptical of such claims. -
Clouds provide negative feedback
RW1 - In reference to Sphaerica's question, on cloud feedback, keep in mind that both Sphaerica and I (as in my post here) are asking about changes in cloud response from the current state, which are what will amplify or (as you seem to be arguing) damp temperature changes. -
Bob Lacatena at 23:40 PM on 22 April 2011Clouds provide negative feedback
RW1, Now that we've identified the flaws in your calculations and can do away with them... 1) Do you have any actual evidence at all that cloud feedbacks would or should be negative? 2) Do you have any response to the question that I've posed 3 times (posts 27, 71, 90) and KR once (post 94)? For the fifth time, do you have any response to the fact that multiple studies, using a wide variety of methods, all point to a climate sensitivity of 3 or greater, and so the chance of cloud feedbacks being negative or neutral is slim to none? -
Bob Lacatena at 23:25 PM on 22 April 2011Clouds provide negative feedback
115, RW1,The surface cannot be "getting" 517 watts in, as it's only emitting 396 W/m^2.
You are ignoring the 23 reflected, 17 transported through thermals and 80 transported through evapotranspiration (396 + 23 + 17 + 80 = 516).Show me the energy in = energy out calculations...
Apologies... I mistyped the 290. The number is for space is 341 in and 341 out (79 reflected by clouds + 23 reflected by the surface + and 239 emitted by the atmosphere/clouds). The 239 comes from ignoring the reflected incoming radiation, which for all intents and purposes never affects the system. So 341 in - 102 reflected = 239. Similarly, 341 out - 102 reflected = 239. Everything balances. -
Bob Lacatena at 23:18 PM on 22 April 2011Clouds provide negative feedback
113, RW1,From the ISCCP data, which says that clouds cover 2/3rds of the surface. This means 1/3rd of the surface is clear sky (i.e. cloudless).
No. The ability of clouds to absorb IR is different from "clear sky" (i.e. the atmosphere). One cannot simply take a percentage. It's a meaningless estimation.If my calculations are in error, why do they accurately predict the correct brightness temperature of 255K?
Where do you do that, and how? -
Tom Curtis at 21:59 PM on 22 April 20112nd law of thermodynamics contradicts greenhouse theory
damorbel @1011, where I discussing the mechanisms of the greenhouse effect I would agree with you. As it happens, however, I am discussing the claim by some deniers that the GHE violates the second law of thermodynamics because the Surface radiation is greater than the incoming Solar radiation and/or because the back radiation is absorbed by the surface, which is warmer than the atmosphere. Neither of those claims is based on the density/temperature profile of the atmosphere, and therefore a simplified model for discussing those objections need not include those profiles. Now if you have a more subtle 2nd law objection to the GHE, just state for the record that your objection is not based either on S < Surf, and the surface absorbing AtmDn; and that the model described above does not violate any laws of thermodynamics and then we can proceed on to your more subtle objections. On the other hand, if you do not have a second law objection, may I remind you of the topic, and that the Moderators have already told you:"The claim that lapse rate or gravitational compression is responsible for the GHE is not directly relevant to this thread, as has already been addressed in multiple links provided. Please take this particular point of discussion elsewhere."
Consequently if you are not explicitly discussing 2nd law issues, may I suggest you take your discussion elsewhere. -
Alec Cowan at 21:23 PM on 22 April 2011The e-mail 'scandal' travesty in misquoting Trenberth on
@Ken Lambert #157 Good for you Ken that you set aside figures; whenever you want to get back to that, go to "It's not warming" or any other more suitable post and let me know. I hope that severe cooling I pointed during that very specific period of 2010 has made you realize you need to learn more about how the planet works. You know I'm not patient with people who reason in a way that reminds me the sound of chalk continually squeaking against a blackboard -unless they are, admittedly, students-. Now you are coming back to what is solid ground for you: Rhetorics.Yet if there were a 'hack' or 'leak' of emails between businesspersons engaged in the oil, nuclear or coal industries, which cast doubt on their theories and public positions - I would bet "London to a brick" that such emails would be screaming out of the internet, the environmentalist industry, and the hackers or leakers would be extolled as public whistleblower heroes deserving of the 'Assange prize'.What an easy way to get some real states. Wait! You said "I would". I say you was likely thinking along the way of "it takes one to know one", but sadly it was just your mirror. You speak of Assange and forget that there are many people (CIA, SMS, RVS, MI6, etc.) that knew those mails -and milliards more- and that they have much to gain (or lose), not from showing themselves as hackers but from following the "inner web of the conspiracy" and revealing it in the proper moment. Imagine Russia, with a lot to lose if this anti AGW politics go on, *not having* (was it good, the *spell* marks: alakazaam!) access to those emails or other "incriminatory" emails and *not having* good scientists to support an explanatory campaign. The decent thing to do is a reality check. The fact is that all get us back to a Hollywood plot and a screenplay-like partial withdrawal of logic that accompanies it if you like to enjoy the movie. Your diasporic urban tribe have made from the "climategate mistique" its own version of Antitrust(2001) with your kin playing the character of Ryan Phillipee. Or maybe it has touches of The Da Vinci Code. Whatever, but the problem stays when one's epistemology is dictated in front of a TV set and not in an academic hall without the ability to tell the difference. -
Arkadiusz Semczyszak at 21:17 PM on 22 April 2011Lindzen Illusion #1: We Should Have Seen More Warming
Worth be simplified - Figure the first - to this scheme - how lot depends on the positive feedbacks! (Well, the clouds are balanced "to zero".) Their opinions Lindzen - similar to those cited by Dana1981 February 4 - short (in the form of post), he also presented here. “The larger predictions from climate models are due to the fact that, within these models, the more important greenhouse substances, water vapor and clouds, act to greatly amplify whatever CO2 does. This is referred to as a positive feedback.” “For warming since 1979, there is a further problem. The dominant role of cumulus convection in the tropics requires that temperature approximately follow what is called a moist adiabatic profile. This requires that warming in the tropical upper troposphere be 2-3 times greater than at the surface. Indeed, all models do show this, but the data doesn't and this means that something is wrong with the data.” “Under the circumstances, it is reasonable to conclude that the problem resides in the surface data, and that the actual trend at the surface is about 60% too large. Even the claimed trend is larger than what models would have projected but for the inclusion of an arbitrary fudge factor due to aerosol cooling.” “Thus, Santer, et al (2008), argue that stretching uncertainties in observations and models might marginally eliminate the inconsistency. That the data should always need correcting to agree with models is totally implausible and indicative of a certain corruption within the climate science community.” "On the planet the most wonderful constituent is water with its remarkable thermodynamic properties. It's the obvious candidate for the thermostat of our system, and yet in most of these models, all water-related feedbacks are positive.” Lindzen 1989. Main attention: Lindzen then (and today) does not deny the warming! “What we have is data that says that maybe it occurs, but it's within the noise” - 1989 As you can see past the main concerns of Lindzen - against the AGW theory (with all objections against the this term) are - for him - to date. And not just for him for example ... “ ... IPCC misrepresentations that haven't already been dealt with on this site ...” Well, maybe my favorite: Landsea, Christopher W., Gabriel A. Vecchi, Lennart Bengtsson, Thomas R. Knutson, 2010: Impact of Duration Thresholds on Atlantic Tropical Cyclone Counts*. J. Climate, 23, 2508–2519.: “Upon adding the estimated numbers of missed TCs, the time series of moderate to long-lived Atlantic TCs show substantial multidecadal variability, but neither time series exhibits a significant trend since the late nineteenth century, with a nominal decrease in the adjusted time series. Thus, to understand the source of the century-scale increase in Atlantic TC counts in HURDAT, one must explain the relatively monotonic increase in very short-duration storms since the late nineteenth century. While it is possible that the recorded increase in short-duration TCs represents a real climate signal, the authors consider that it is more plausible that the increase arises primarily from improvements in the quantity and quality of observations, along with enhanced interpretation techniques.” And this - "to set" example this Figure. -
CBDunkerson at 20:56 PM on 22 April 2011CO2 was higher in the past
5.35 W/m^2 is the measured radiative forcing constant for carbon dioxide. As for terminology... we are currently in an interglacial (i.e. relatively warm) period of the ongoing ice age (i.e. geological period where large ice caps are present). What you have probably heard people saying is that raising CO2 to ~500 ppm might prevent the next glacial period entirely. That is, normally we would expect the current interglacial period to end some time in the next 15,000 years or so and then be followed by a long period of increasing cold which would cause glaciers to spread out from the poles for ~90,000 years and then retreat as the next warming cycle comes around. However, if CO2 were raised to 500 ppm then it would likely take more than 100,000 years to return to pre-industrial levels (barring some new technology to sequester it faster than would happen naturally) and could thus keep the planet warm enough that we skip the next glacial cycle entirely. That'd actually be a good thing... but given that it is thousands of years away not quite as pressing as dealing with the warming we will see over the next two centuries. -
damorbel at 20:04 PM on 22 April 20112nd law of thermodynamics contradicts greenhouse theory
Re #1010 Tom Curtis you wrote:- "But we are discussing an idealized system kept deliberately simple for clarity of discussion." Surely that is the whole point? That is why I offered the constant temperature/density by way of comparison. Simplified models are indeed very useful to help clarify the basics but they only work if they include the major parameters. Leaving out the gravitational force {- snip -}Moderator Response: [muoncounter] Gravitational lapse rate was declared off topic at #972. It's been demonstrated repeatedly that this idea is irrelevant here. -
Tom Curtis at 19:21 PM on 22 April 20112nd law of thermodynamics contradicts greenhouse theory
Damorbel @1009: Yes, the radiation up is less than the radiation down from the atmosphere because the atmosphere is thicker and warmer closer to the Earth than near the tropopause. But we are discussing an idealized system kept deliberately simple for clarity of discussion. Use of such simplified models is standard in physics, whether it be with gravitational equations from point masses, or the use of frictionless surfaces. There is no principled objection to using such simplified models, and in the simplified model, AtmUp = AtmDn. It follows that your point is a mere distraction rather than a contribution. -
damorbel at 16:30 PM on 22 April 20112nd law of thermodynamics contradicts greenhouse theory
Re #998 Tom Curtis you wrote:- "Because thermal radiation is the same in all directions" At the molecular level - yes. But the atmosphere is denser at lower levels so there are more molecules emitting. Also the lower levels are warmer so they emit more intensely. This should not be a surprise since it corresponds with the visible part of the spectrum, there is a net output of radiation, it is the reason why stars shine. Further you wrote:- "if the atmosphere were 303 K, then it would radiate 480 w/m^2 up, and the same down. That would violate conservation of energy." If you accept that the exchange of energy between layers of the atmosphere can be characterised in W/m^2 then "480 w/m^2 up, and the same down" merely makes the case for constant density and temperature. These conditions do not exist in the atmosphere so it makes for a rather pointless discussion. There is no point in arguing about 'violation of conservation of energy' unless you account for all energy, assuming constant density (or temperature) in a gravitationally bound system automatically excludes 'conservation of energy'. -
Albatross at 15:32 PM on 22 April 2011A Convention for Persons Displaced by Climate Change
Tom @44, After Googling "UNEP +2005 +50 million +refugees" earlier today and reading through some of the hyperventelating drivel from some media outlets (including Der Spiegel) and the denialosphere, your post came as a breath of fresh air. Thanks for this and for stating the facts. This is again another case of the contrarians and deniers of AGW demonstrating their bias, prejudice and asymmetrical skeptical and critical thinking skills. Disgusting. Tom, data from the iDMCmay be helpful. Specifically, see their 2009 report titled "Monitoring disaster displacement in the context of climate change ", in which they state: "At least 36 million people were displaced by sudden-onset natural disasters which occurred in 2008, including over 20 million displaced by climate-related, sudden-onset disasters, according to a new report by NRC/IDMC and OCHA. In comparison, 4.6 million people were newly internally displaced during the year by conflict and violence. " I do not know much about iDMC, so caveat emptor-- but from what little I did read tonight they seem reputable and work with OCHA. -
trunkmonkey at 15:26 PM on 22 April 2011CO2 was higher in the past
Ok,ok I'm stumbling over nomenclature here. I never liked the icehouse/hothouse, snowball thing anyway. We are DEFINITELY in a glacial period. Glacial periods have their ocillations. We are currently in a warm phase. Our glacial period is called the Pleistocene. It has been with us for a couple million years, and happens to coincide, generally, with the evolution of the brains that allow us to carry on this discussion. The last glacial period of any consequence was the so called KT about 230 mya at the Permian-Triassic boundary. This one coincided with the greatest extinctions in the history of life. The notable one before that was at the end of the Ordovician about 450 mya. There were extinctions but only a few liverworts and mosses and possibly insects had made it on to land. The really wierd thing is that there are glacial tillites with a carbonate cap in Australia, and if we can believe the apparent polar wander paths Australia was pretty close to the equator then. There was another glacial period about 650 million years ago in the Proterozoic. Everynoe starts getting really grumpy and calling each other names and the apparent polar wander paths diverge before this. You can see that glacial periods are rare in earth history, ocurring roughly every 200 my. Between hese periods Gloval Average Temperature and CO2 are thought to be higher than now. Where dies the 5.35 come from in DeltaF = 5.35*ln(C/C0)? -
Philippe Chantreau at 14:42 PM on 22 April 2011The e-mail 'scandal' travesty in misquoting Trenberth on
KL "AGW enthusiasts are terribly worried about 'stealing' of emails that cast doubt on the measurements behind the AGW case" This characterization is wrong and insulting in several ways. The extent to which deniers are willing to twist data, misrepresent it or put forth outright lies has been extensively demonstrated. Christopher Monckton is a case in point, backing up at nothing to mislead his audience, even tilting a graph to give the impression that there is no trend. I am especially concerned of late with McIntyre and McKitrick fraudulent paper on Mann's statistical methods. I strongly recommend all to read in details the DeepClimate post about this pathetic bag of lies. http://deepclimate.org/2010/11/16/replication-and-due-diligence-wegman-style/ I note also that the transparency advocated by deniers falls on deaf ear with Wegman, but the denier blogs have been eerily silent about it. If it's OK for e-mails to be stolen, shouldn't the materials for the Wegman report be released? Where are the skeptics advocating for it? Nowhere, because their double standards prevent it. BP has been challenged on several occasions on his accusations of fraud that were exclusively based on misunderstanding of materials referred on his site, his best answer was "I'll get back to you." Considering what deniers like McIntyre & McKitrick, Monckton, Beck, Wegman, etc, etc are willing to pull off, no piece of information whatsoever is safe in their hands. Even an invitation for lunch will be shown as evidence of conspiracy or other lunatic nonsense. Yes the reality based among us are worried. Deniers, of course, are not. After all, they have savory characters like Monckton, Wegman or Cuccinelli on their side, what could possibly go wrong?Moderator Response: [DB] Hotlinked URL. -
RW1 at 14:25 PM on 22 April 2011Clouds provide negative feedback
Sphaerica (RE: 110) "The atmosphere absorbs 78 from inbound solar radiation, 17 from thermals, 80 from evapostranspiration/latent heat, and 356 from surface radiation, for a total of 531. It radiates 169 to space from the atmosphere, 30 to space from clouds, and 333 back to the surface, for a total of 532. So the entire system gets 290 in from space, and sends 290 out to space. The atmosphere gets 531/532 in, and sends 531/532 out. The surface gets 517/516 in, and sends 516/517 back out... Each is in balance." Show me the energy in = energy out calculations that demonstrate COE is being satisfied? There is 239 W/m^2 coming in and 239 W/m^2 leaving. The surface cannot be "getting" 517 watts in, as it's only emitting 396 W/m^2. -
RW1 at 14:13 PM on 22 April 2011Clouds provide negative feedback
Sphaerica (RE: 110) "RW1, ...the clear sky only absorbs a total of 131 W/m^2 (0.33 x 396 = 131)... Where do you get this from?" From the ISCCP data, which says that clouds cover 2/3rds of the surface. This means 1/3rd of the surface is clear sky (i.e. cloudless). "But you can't tell how much the "clear sky" absorbs. The "clear sky" does not absorb separately from the clouds. The two are not distinct. Clouds form and dissipate very quickly." The average coverage is what matters to the energy flows. If the surface is 1/3rd clear sky, this means that 1/3 or 0.33 of the average emitted surface power passes through the clear sky. If my calculations are in error, why do they accurately predict the correct brightness temperature of 255K? -
Clouds provide negative feedback
RW1 - "This isn't correct because the clear sky only absorbs a total of 131 W/m^2 (0.33 x 396 = 131). If the clear sky is emitting a total of 169 W/m^2 up - that's more than the energy it absorbs, which is impossible." As Sphaerica quite clearly states, this is completely incorrect. The atmosphere receives about 532 W/m^2 from various sources, and puts out about 532 W/m^2, thus conserving energy. 131 of the input is direct solar energy. 169 of the output is IR to space. Each is just a portion of the energy flowing through the atmosphere, no impossibilities whatsoever. You are displaying a serious misunderstanding the Trenberth energy diagrams, which explains many of the (incorrect) issues you have raised. -
Clouds provide negative feedback
RW1 - "...40 W/m^2 of it passes straight through the atmosphere to space and 30 W/m^2 of the 396 is emitted through the clouds..." No - 30 W/m^2 is emitted by the clouds, heated by radiation, convection, and latent heat. This is not a direct re-radiation or window through the clouds. -
Albatross at 13:59 PM on 22 April 2011The e-mail 'scandal' travesty in misquoting Trenberth on
mclamb6 @158, Well stated, bravo. Those in denial had better be careful what they claim concerning the ARGO data....that is all I'll say for now ;) And all, really, Dr. Trenberth has a long time ago had the last word on this on his web page. -
mclamb6 at 13:49 PM on 22 April 2011The e-mail 'scandal' travesty in misquoting Trenberth on
Actually, Ken, there are two distinct concerns: 1. Stealing of emails. It is telling that you find BP's contribution "sensible". The emails were stolen. Point blank. It would be something else entirely if they were produced by the university pursuant to some type of stated policy of which the particular employee either explicitly or tacitly accepted as a term of employment. Whether BP (or anyone) maintains a separate personal and business account is quite irrelevant. It's a question of expectation. You don't expect your emails business or otherwise to be stolen and published without any authorization. BP and your efforts to defend such actions is moral relativism at its finest--i.e. it's ok because he agrees with the spin given to such emails. Everyone should be concerned about this type of behavior. It's in the same vein as identity theft. 2. Excerpting and misrepresenting the emails as a means of tarnishing the scientists (primary) and the science (secondary). You are engaging in the latter even at 157. The theory is sound as are the observations supporting the theory. Nonetheless, you cherry pick ARGO measurements (which apparently is the new gold standard despite the fact that the ARGO measurements are being refined and there isn't even close to a statistically significant period of observation) and attach your cherry picked measurements to your skewed interpretation of Trenberth's email. At that point, the KL version is a gross distortion of Trenberth's position and the science. If you think that folks here are concerned only about "stealing", you need to re-evaluate what has been posted. -
Bob Lacatena at 12:49 PM on 22 April 2011Clouds provide negative feedback
109, RW1,...the clear sky only absorbs a total of 131 W/m^2 (0.33 x 396 = 131)...
Where do you get this from?If the clear sky is emitting a total of 169 W/m^2 up - that's more than the energy it absorbs, which is impossible.
But you can't tell how much the "clear sky" absorbs. The "clear sky" does not absorb separately from the clouds. The two are not distinct. Clouds form and dissipate very quickly. There are only three components to the ("Trenberth") system; space, atmosphere, and surface. Different components and interactions are represented in each (land/ocean at the surface, sky/clouds in the atmosphere), but you can't separate them for the purposes of Watts bookkeeping (except where he has explicitly done so). The atmosphere absorbs 78 from inbound solar radiation, 17 from thermals, 80 from evapostranspiration/latent heat, and 356 from surface radiation, for a total of 531. It radiates 169 to space from the atmosphere, 30 to space from clouds, and 333 back to the surface, for a total of 532. So the entire system gets 290 in from space, and sends 290 out to space. The atmosphere gets 531/532 in, and sends 531/532 out. The surface gets 517/516 in, and sends 516/517 back out... Each is in balance. You cannot say that the clear sky absorbs 131.Moderator Response: [DB] FYI, Chris Colose is explaining something along these lines to Kevin McKinney over at Open Mind as wespeaktype. Very understandable. -
RW1 at 12:32 PM on 22 April 2011Clouds provide negative feedback
Sphaerica (RE: 105), "This entire paragraph is a misinterpretation of the diagram. You are reading too much into it and seeing things that are not there. 40 pass through the atmosphere (cloudy or not) directly from the surface into space. 356 are absorbed by either the clouds or the atmosphere. His diagram does not distinguish." Have you read the paper? The diagram does distinguish. If you look carefully, it shows that of the 396 W/m^2 emitted at the surface, 40 W/m^2 of it passes straight through the atmosphere to space and 30 W/m^2 of the 396 is emitted through the clouds for a total transmittance of 70 W/m^2 - meaning 70 W/m^2 of the surface emitted 396 goes straight out to space without being absorbed by the atmosphere. "169 is emitted into space from the atmosphere. Again, like the 30 from clouds, you cannot separate this by source." This isn't correct because the clear sky only absorbs a total of 131 W/m^2 (0.33 x 396 = 131). If the clear sky is emitting a total of 169 W/m^2 up - that's more than the energy it absorbs, which is impossible. The 169 W/m^2 represents the total amount the atmosphere, both cloudy and clear sky, is emitting up out to space. -
Bob Lacatena at 12:18 PM on 22 April 2011Clouds provide negative feedback
107, RW1,I've presented much more evidence than just my initial calculations...
Like what? I remember nothing of the sort. I've seen nothing of any weight or importance in anything you've said so far. And no, I'm not going back to re-read the convoluted thread. If you have valid points to make, it is easy enough to state them. An unwillingness to do so speaks volumes....but burden of proof is on those claiming a positive cloud feedback...
Huh? And why would that be? The burden of proof falls on the person trying to convince other people. I'm not trying to convince you of anything. You're trying to convince me. And so far you have a set of calculations that are invalid, logic that is insufficient, and hand waving supported by "I don't think you've been paying attention." -
Tom Curtis at 12:10 PM on 22 April 2011A Convention for Persons Displaced by Climate Change
DB: Thanks - I wondered what the problem was. I included the link so there is no need to actually fix the graphic. -
Tom Curtis at 11:25 AM on 22 April 2011A Convention for Persons Displaced by Climate Change
As I'm coming late to this topic, I want to firstly and primarily thank Dan Olen whose references to primary sources is invaluable. As I understand the situation, in 1995, Norman Myers made a prediction that the number of environmental refugees would grow from 25 million in 1995 to 50 million by 2010. By "refugee" Myers' meant anybody who was currently temporarily displaced, or who had become permanently displaced from their normal place of residence. By "environmental refugee" he meant any "refugee" who had been displaced due to a change in the environment in which they lived, including such changes are increased population and the construction of dams. He explicitly includes people who are displaced because population growth in their original place of residence has been so great that there is insufficient farmland for them to make a living there. He does indicate that by 2025 climate change will exacerbate the situation. But, he is certainly not claiming that there would be 50 million "climate change refugees". For instance, he expects by 2050 (and in the absence of a major engineering program to combat the problem) 12 million displaced people in Egypt due to "sea level rise", but attributes most of that rise to subsidence of the Nile Delta, primarily because the Aswan dam filters silt from the Nile (p 143). In 2005 Myers summarized his report for UNEP, but without the prediction for 2010. At some later date, an unknown system operator at UNEP placed a map showing areas of environmental distress:
(Hosted by News Ltd)
There is, of course, nothing wrong with that, but they placed a title on the map saying "Fifty Million Climate Refugees by 2010"
(Hosted by WUWT)
That is, of course, completely wrong, and completely misrepresents both the original study and the 2005 report. So there has not been a failure of science or prediction at UNEP, but a failure at communication. For this, Myers may be partially responsible in using a non-standard definition of refugee, although one that he did not invent. On the other hand "environmentally displaced person" is an awkward coinage, and he did provide a clear de facto definition of his usage of the term "environmental refugee" as the first paragraph of his original study and the subsequent report. He also carefully discusses the definition of "environmental refugee" and the difficulty distinguishing them from economic "refugees" on pages 17 and 18 of his paper.
Culpable or not, his terminology is unfortunate in that it has lead to widespread misunderstanding. One example of the misunderstanding is in the original post in which David Hodgkinson writes, "The most cited estimate is 200 million climate change migrants by 2050 or one person in every forty-five." According to Wikipedia, that "most cited figure" comes from a subsequent paper by Myers (Myers, N. (1997). ‘Environmental Refugees’, Population and Environment), and therefore clearly refers to "environmental refugees and not just climate change refugees.
So, was the prediction wrong? Well clearly we cannot find out by looking at UNHCR figures. The UNHCR only classifies as refugees or internally displaced people those who "owing to a well-founded fear of being persecuted for reasons of race, religion, nationality, membership of a particular social group or political opinion" has either fled their country (refugees) or moved from their normal place of residence within the borders of their original country (Internally Displaced People) which categories are by definition not environmental refugees. The UNHCR also classifies as IDP a small number of people rendered homeless by natural disasters, but for the vast majority of environmental refugees who have found some form of home, even if it is just a shared room in a third world slum, they do not come under the UNHCR's definition.
To actually know if the prediction was correct or incorrect, we would need an extensive study of international and intra-national migration and the reasons for it, since 1995. Certainly vastly more than 25 million people have moved their place of residence permanently or semi-permanently since 1995, but how many have done it for environmental reasons?
Adelady has already indicated the 4 million Pakistani's still homeless as a result of the 2010 flood. To that we can add 1.24 million Chinese displaced by the Three Gorges Dam. We can add a further 100 thousand environmental "refugees" from Hurricane Katrina (the population loss of New Orleans minus the trend population decline over the 6 years since the Hurricane). What else? I wouldn't know where to look to find out, but would greatly appreciate any additions to the list.
Moderator Response:[DB] Tom, you can't link directly to a picture or graph contained in PDF format with the intent to display it as a picture or graphic here. PNG, GIF or JPG work best. Gremlins dead, fixed image.
-
Ken Lambert at 11:06 AM on 22 April 2011The e-mail 'scandal' travesty in misquoting Trenberth on
Alec Cowan #156 BP #154 Amongst Alec's semantic games there is an important point emerging in the debate following on from BP's sensible contribution. Notice that the AGW enthusiasts are terribly worried about 'stealing' of emails that cast doubt on the measurements behind the AGW case. Yet if there were a 'hack' or 'leak' of emails between businesspersons engaged in the oil, nuclear or coal industries, which cast doubt on their theories and public positions - I would bet "London to a brick" that such emails would be screaming out of the internet, the environmentalist industry, and the hackers or leakers would be extolled as public whistleblower heroes deserving of the 'Assange prize'. One man's thief is another man's hero. Think of it an an involuntary early 'Freedom of Information' disclosure for the public benefit. The facts are that the 'travesty' emails are revealed and give us an insight into the truth of the overheard conversation. This truth shows that Dr Trenberth is frustrated with the 'inadequacy' of the measurement of warming imbalance to support the AGW theory and models. There are two ways to interpret these revelations. One is that the AGW models and theory are right and the maesurement is 'inadequate' or wrong. The other is that the measurement is right, and the theory and models are 'inadequate' or wrong. Take your pick, but if better and more extensive measurement keeps getting the theory wrong - time to look at the theory. -
RW1 at 11:01 AM on 22 April 2011Clouds provide negative feedback
Sphaerica (RE: 103), "Aside from your calculations (which we're still trying to work through), what other evidence do you have of negative cloud feedback?" I don't think you've been paying attention. I've presented much more evidence than just my initial calculations (I suggest you go back and reread the thread from the beginning), but burden of proof is on those claiming a positive cloud feedback, which subsequently leads to an enhanced warming warming of 3 C, rather than a more modest 1 C in line with the system's directly measured response to surface incident energy. -
Bob Lacatena at 11:00 AM on 22 April 2011Clouds provide negative feedback
104, RW1,positive cloud feedback for GHG 'forcing' at the surface is contradictory to the system's response to solar 'forcing' at the surface.
Please explain. This makes no sense.For additional GHG 'forcing' it's nearly a factor of three greater.
Please explain. This makes no sense.Ultimately, for net positive cloud feedback to be supported, this has to be explained by quantifying specifically how the feedback causes this much change for the next 3.7 W/m^2 at the surface from GHG 'forcing' and why it does not for the original 98+% (239 W/m^2) incident on the surface from the Sun.
Please explain. This makes no sense to me whatsoever. -
Bob Lacatena at 10:56 AM on 22 April 2011Clouds provide negative feedback
101, RW1,Trenberth actually has it being less than half...
This is your interpretation, and it's incorrect, as you will see below....which means the net effect through the whole atmosphere is half goes up out to space and half goes down toward the surface.
This is incorrect (probably because it is oversimplified).That aside...
This entire paragraph is a misinterpretation of the diagram. You are reading too much into it and seeing things that are not there. 40 pass through the atmosphere (cloudy or not) directly from the surface into space. 356 are absorbed by either the clouds or the atmosphere. His diagram does not distinguish. 30 are emitted from clouds into space. You cannot say this is part of the 396 (some of it will be from thermals and evapostranspiration/latent heat, and some is the energy absorbed by the atmosphere from inbound radiation... the individual sources are not relevant, and cannot really be separated). 169 is emitted into space from the atmosphere. Again, like the 30 from clouds, you cannot separate this by source. 333 is radiated back down the surface, again from the atmosphere and clouds, without distinction. Specifically, in your calculations:326 - 169 = 157 W/m^2
You can't do this, because the 169 is from the atmosphere, which is also heated by solar input, thermals and evapostranpiration/latent heat. You can't just allocate all of that to the radiation from the surface.157 emitted down from the atmosphere...
No. You can't say this. 333 emitted down from the atmosphere + clouds, that's as much as you can specify.A lot of confusion lies in Trenberth having 78 W/m^2 of the incoming energy from the Sun absorbed by the atmosphere and brought to the surface as 'back radiation'.
But he doesn't have that. In his diagram (which is already a simplification) it is absorbed by the atmosphere and you can't then say where it goes, any more than you can identify the molecules from a cup of water after you've dumped it into a boiling pot. The atmosphere is heated from above by the sun (78), and from below through the processes of radiation (356), thermals (17), and evapostranspiration/latent heat (80). It sheds heat by radiating upward (199, 169 atmosphere + 30 clouds) and downward (333). You cannot do from these numbers what you are trying to do, which is to allocate some measure of this specifically to clouds. Which isn't to say that it can't be done from appropriate sources, or that the information isn't available, only that your calculations here do not and can not do it. -
RW1 at 10:38 AM on 22 April 2011Clouds provide negative feedback
Sphaerica (RE: 93), "5. You think the reduction is so great that 1.9 isn't a problem -- it's not a dangerously high amount of warming. I have not made this claim, though I'm not sure a 1.9 C rise would be 'dangerous'. "6. You discount the fact that the lapse rate feedback might not be as great as estimated, or that CO2 and albedo feedbacks might be greater or kick in sooner than estimated, or that anthropogenic CO2 additions could actually increase with human population growth and expanding industrialization. 7. You discount the fact that other studies point to a climate sensitivity of 3+, which imply that that the cloud feedback estimates are either correct, or that any error is offset by underestimations of other positive feedbacks (or over-estimation of the lapse rate negative feedback). 8. You discount the fact that we've already seen the climate warm by 0.8˚C this century without a noticeable negative cloud feedback, i.e. that the climate is obviously sensitive enough to swing 0.8˚C in a mere 100 years (0.6˚C of that in only the last 30 years) despite your proposed fast acting negative cloud feedback." You're putting a lot of words in my mouth and making a lot of assumptions. I have not discounted anything entirely. Lots of things or combinations of things are theoretically possible. All the evidence has to be weighed very carefully. There are many lines of major contradictory evidence against net positive cloud feedback. I have presented many here, but the simplest and perhaps most significant is positive cloud feedback for GHG 'forcing' at the surface is contradictory to the system's response to solar 'forcing' at the surface. For additional GHG 'forcing' it's nearly a factor of three greater. Ultimately, for net positive cloud feedback to be supported, this has to be explained by quantifying specifically how the feedback causes this much change for the next 3.7 W/m^2 at the surface from GHG 'forcing' and why it does not for the original 98+% (239 W/m^2) incident on the surface from the Sun. -
Bob Lacatena at 10:32 AM on 22 April 2011Clouds provide negative feedback
100, RW1,...one piece of evidence among many in support of negative cloud feedback...
Aside from your calculations (which we're still trying to work through), what other evidence do you have of negative cloud feedback? -
Clouds provide negative feedback
RW1 - I begin to see the problem. You are not distinguishing between the current state of affairs (from the Trenberth diagram) and the feedbacks, or how those values will change with temperature changes. All of the studies show a mean estimate of slightly positive feedback for clouds, with Dessler's including a small possibility of cloud feedback being negative. Do you have any issues with the referenced papers mentioned in this thread? I do not recall seeing any such in this thread so far. If you don't, then you are not actually addressing feedback. -
RW1 at 09:30 AM on 22 April 2011Clouds provide negative feedback
Sphaerica (RE: 98), "How do you get "half?" Citation, please." Trenberth actually has it being less than half - meaning more of the surface emitted energy absorbed by the atmosphere is emitted up out to space than is emitted down toward the surface (specifically, he has 157 W/m^2 emitted down and 169 W/m^2 emitted up). So using his numbers for this component would actually result in even more energy reflected away than retained. That aside, when the atmosphere (clouds or clear sky) absorbs surface emitted LW infrared, it re-emits it equally in all directions, which means the net effect through the whole atmosphere is half goes up out to space and half goes down toward the surface. Using Trenberth's numbers, he has the surface emitting 396 W/m^2. Of this, he has 70 W/m^2 passing through unabsorbed straight out to space (40 W/m^2 through the clear sky and 30 W/m^2 through the cloudy sky). 396 - 70 = 326 W/m^2 absorbed by the atmosphere. He then has 169 W/m^2 designated as being emitted up out to space, so 326 - 169 = 157 W/m^2, which is the remainder and is the amount emitted down toward the surface. 70 + 169 + 157 = 396 W/m^2 total emitted by the surface. 70 + 169 = 239 W/m^2 emitted to space. 239 coming in from the Sun + 157 emitted down from the atmosphere = 396 W/m^2 at the surface. A lot of confusion lies in Trenberth having 78 W/m^2 of the incoming energy from the Sun absorbed by the atmosphere and brought to the surface as 'back radiation'. Only it's not 'back radiation', it's 'forward radiation' yet to reach the surface that last originated from the sun - as opposed to 'back radiation' being energy that last originated from the surface. These distinctions are absolutely critical to understanding the constraints Conservation of Energy puts on the system relative to all the energy flows.Moderator Response: [DB] "it's 'forward radiation' yet to reach the surface that last originated from the sun" Parse:Fail -
JMurphy at 09:30 AM on 22 April 2011Lindzen Illusion #1: We Should Have Seen More Warming
I would ask rhjames to point out any of that "deliberately misrepresented scientific evidence" by the IPCC, but realise it will be a waste of time and he/she will just move on to the next so-called skeptical disinformation meme. -
Stephen Baines at 09:17 AM on 22 April 2011Lindzen Illusion #1: We Should Have Seen More Warming
I would also point out to rhjames that it appears Lindzen in one third of a single testimony made more demonstrably incorrect or misleading statements than an army of skeptics could uncover in the entire IPCC AR4 report, despite its thousands of pages, hundreds of authors and thousands of reviewers stumbling over each other. That's actually quite amazing. A ratio of >3 mistakes:1 Lindzen vs a ratio of <<2 mistakes:100 IPCC authors. IPCC wins!!! -
RW1 at 09:07 AM on 22 April 2011Clouds provide negative feedback
Sphaerica (RE: 93), "Let me summarize my understanding of your logic. 1. Your personal calculations about clouds, based purely on Trenberth's "Global Energy Flows" diagram, "suggest that in aggregate the net effect of clouds is to cool rather than warm." (you haven't actually made this case, but it's your main premise)." Yes. "2. The scientists behind the models admit that the cloud feedbacks are uncertain, vary between models, and provide an important positive feedback (no need to exaggerate this further... leave it at "important"). Correct. The exact wording in the IPCC report is "significant uncertainties, in particular, are associated with representation of clouds, and in the resulting cloud responses to climate change." "3. Your assumption is that since you've "proven" that clouds cool rather than warm, a positive feedback is impossible (despite your lack of understanding of the physics behind how the clouds work on atmospheric temperatures, how they form, and how their formation will be affected by rising temperatures, and the fact that not all clouds are created equal)." No, I've made no claim that anything is impossible. I've presented several lines of evidence and logic against positive cloud feedback. The calculations using Trenberth's numbers are one piece of evidence among many in support of negative cloud feedback, but the calculations in and of themselves do not 'prove' that the cloud feedback is negative. 4. Completely eliminating all positive feedback from clouds reduces estimated sensitivity from 3.1 to 1.9. Yes, 1.9 C for neutral cloud feedback. What they don't show is how much less the sensitivity would be with even a slightly negative cloud feedback. -
Bob Lacatena at 08:57 AM on 22 April 2011Clouds provide negative feedback
96, RW1,...the calculation for the amount of surface emitted energy absorbed by the clouds...
Please clarify this calculation. -
Bob Lacatena at 08:56 AM on 22 April 2011Clouds provide negative feedback
96, RW1,...emitted from the surface (396 W/m^2) absorbed by the clouds, half of which is emitted downward toward the surface.
How do you get "half?" Citation, please.What I've shown is - using Trenberth's numbers at least, the amount of surface emitted energy clouds retain is less than the amount of incoming energy they reflect away
I don't see this, or how you could arrive at this. Trenberth's own diagram does not distinguish between back radiation from clouds versus the atmosphere. Can you clarify how you arrive at that part of your calculation? -
Stephen Baines at 08:50 AM on 22 April 2011Lindzen Illusion #1: We Should Have Seen More Warming
Say rhjames...care to point to any of those supposed IPCC misrepresentations that haven't already been dealt with on this site? If not, do you care to continue discussion on the relevant threads dealing with those already considered?
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