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All IPCC definitions taken from Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Annex I, Glossary, pp. 941-954. Cambridge University Press.

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Comments 87601 to 87650:

  1. Arkadiusz Semczyszak at 21:17 PM on 22 April 2011
    Lindzen 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.
  2. CO2 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.
  3. 2nd 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.
  4. 2nd 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.
  5. 2nd 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'.
  6. A 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.
  7. CO2 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)?
  8. Philippe Chantreau at 14:42 PM on 22 April 2011
    The 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.
  9. Clouds 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.
  10. Clouds 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?
  11. 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.
  12. 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.
  13. The 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.
  14. The 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.
  15. Clouds 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 we speak type. Very understandable.
  16. Clouds 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.
  17. Clouds 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."
  18. A 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.
  19. A 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.

  20. The 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.
  21. Clouds 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.
  22. Clouds 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.
  23. Clouds 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.
  24. Clouds 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.
  25. Clouds 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?
  26. 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.
  27. Clouds 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
  28. Lindzen 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.
  29. Stephen Baines at 09:17 AM on 22 April 2011
    Lindzen 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!!!
  30. Clouds 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.
  31. Clouds provide negative feedback
    96, RW1,
    ...the calculation for the amount of surface emitted energy absorbed by the clouds...
    Please clarify this calculation.
  32. Clouds 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?
  33. Stephen Baines at 08:50 AM on 22 April 2011
    Lindzen 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?
  34. Stephen Baines at 08:41 AM on 22 April 2011
    Muller Misinformation #4: Time to Act
    Billy Joe, I too think people have been more than patient with Gilles. He tried to engage in what was essentially a sematic argument over use of the word "exist" (Echoes of Bill Clinton??). Oi..and that argument was an poorly disquised attempt to shift topic to one already covered elsewhere, extensively, on this site. You can look at those discussions to your heart's content, although I would suggest taking some aspirin first. It's not buried either you can easily find recent postings to those threads using in post links or the handy link up top. I think this site is amazingly well organized! Let's keep it that way and stay on topic.
    Response:
    [DB] Most did not see the many trolling comments of Gilles that the moderators deleted.  A selection from his final day's output:

    Gilles at 15:41 PM on 19 April 2011

    what's the weather in australia BTW?

    Gilles at 15:41 PM on 19 April 2011

    hope your employer doesn't mind if you loose time to track my posts on this forum

    Gilles at 15:40 PM on 19 April 2011

    I'm having breakfast, it's a funny way to start the day :)

    Gilles at 15:39 PM on 19 April 2011

    yes, you're definitely getting nervous :)

    Gilles at 15:36 PM on 19 April 2011

    "but they are rapidly exhausting their bag of tricks to hide the incline."

    The incline ? you mean an acceleration ? how much is the acceleration following you ?

    Gilles at 15:35 PM on 19 April 2011

    are you getting nervous, moderators :) ?

    Gilles at 15:29 PM on 19 April 2011
    Gilles at 15:29 PM on 19 April 2011
    how about this one ?

    Discussion of Gilles and trolling should now be considered off-topic.  Back to the topic of this post...
  35. Lindzen Illusion #1: We Should Have Seen More Warming
    Very revealing rhjames @16-- I'll have to keep your blunder and beautiful example of making unsubstantiated accusations, bias and gross generalizing in mind whenever I read your posts in the future. Sad that you can't bring yourself to be a true skeptic and call Lindzen on his errors.
  36. Clouds provide negative feedback
    Sphaerica (RE: 91), "But you appear later to use this result to compute reflectivity for LW radiation from the ground up. Forgive me if I'm mistaken, but as I've said repeatedly... sorting through your swarm of calculations is a nightmare." No, the calculation for the amount of surface emitted energy absorbed by the clouds just happened to come out about the same as the 79 W/m^2 Trenberth designates as being reflected away. Pure coincidence - nothing more. The difference between the weighted average values came out to be 0.20 and 396 x 0.20 = 79.2, which I just rounded to an even 79 - that's all.
  37. Lindzen Illusion #1: We Should Have Seen More Warming
    funglestrumpet "Surely the scientific community needs to develop some mechanism that can impose sanctions on any of their number when they can be shown to have deliberately misrepresented scientific evidence in the way described herein." If they did that, the IPCC would have been closed down years ago.
  38. Clouds provide negative feedback
    Sphaerica (RE: 90), "!?!?!?!?!????? If you don't get this, you have a huge, huge hole in your understanding. You need to know this. It's critical to everything." I mean in terms of energy lost or retained in the system, a watt is watt. That's all. "You say this, but you have not actually demonstrated it, both because your numbers are unclear, and they contain at least one critical flaw (SW vs. LW distinction), and probably many others." The incoming energy from the Sun (341 W/m^2) is all SW radiation. The 79 W/m^2 is the cloud portion of the albedo, which is the incoming SW radiation that is reflected back out to space off of clouds. The energy trapped or retained by the clouds is LW radiation emitted from the surface (396 W/m^2) absorbed by the clouds, half of which is emitted downward toward the surface. The downward emitted amount represents the amount of energy the clouds are trapping or retaining in the system. 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. This means the net effect of clouds is to cool. If the net effect of clouds is to warm, the opposite would be the case - the clouds would retain more surface emitted energy than they reflect away. Does this explain it better?
  39. More Carbon Dioxide is not necessarily good for plants.
    adrian smits, the current UAH decadal trend is 0.049C, i.e. positive, no matter how you might want to look at it. Is that what you call a non-increase in temperature ? What would you call a negative trend, then - an increase in temperature ? But, looking at the data, I bet you were saying the same between 2008 and 2009; then you probably kept quiet for the last couple of yours; now you want to proclaim a non-increase in temperature; soon you'll be keeping quiet again. Must get confusing for you...
    Moderator Response: [mc] Take this to Global warming stopped in ... or a similar temperature thread.
  40. Stephen Baines at 08:06 AM on 22 April 2011
    Lindzen Illusion #1: We Should Have Seen More Warming
    @ finglestrumpet 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? In the professions, there are regulatory bodies that can enforce bans. IN sports there are associations that oversee participation. There are no certification procedures for working scientists - although some societies are moving in this direction for certain activities. There no bodies with such absolute control in science. There are sanctions against clear misdeeds like falsification or plagiarism that can be imposed by the university and funding agencies. Societies or acdemies can revoke membership. In this case, Lindzen can be said the be stating his opinion. He can always claim to be ill-informed or to disagree with other research for arcane reasons that are hard to evaluate. Coming up will hard and fast rules to counteract such arguments would endanger the cherished goal of academic freedom that is so important for free exchange of ideas. You would be opening the gate to political pressure on scientists from all fronts. The one route of enforcement that might work is in the case of testimony to congress. Perjury and lying to congress rules are rarely enforced, as I understand it. Both parties like to engage in political theater. Such rules wouldn't apply to his origninal testimony either since the issue was still up in the air then - Lindzen just ended up on the wrong side of the debate. Later testimony that reiterated positions that were clearly known to him to be incorrect, however, might be subject to sanction. It would be steep hill to climb though...
  41. What was it like the last time CO2 levels were this high?
    Gracias, Daniel!
  42. A Convention for Persons Displaced by Climate Change
    DSL @39, Well, well. This is what you get when you follow the link at WUWT, "This graphic was originally produced for the Environmental Atlas of the newspaper Le Monde diplomatique. We have decided to withdraw the product and accompanying text. It follows some media reports suggesting the findings presented were those of UNEP and the UN which they are not. We hope this clarifies the situation." However, why the heck were they featuring the graphic on their site in the first place then? Somebody at UNEP has some explaining to do.
  43. A Convention for Persons Displaced by Climate Change
    Harry, in the past there weren't so many people. Second, large migrations of people from one place to another already occupied by people haven't been that pleasant for one party or other.
  44. A Convention for Persons Displaced by Climate Change
    "I appreciate the challenge, but just don't have the time to research it" Its not about research really - it about what is acceptable to a particular ideological position. We need solutions to limit CO2 and they need to be solutions that the economic right will support.
  45. A Convention for Persons Displaced by Climate Change
    Harry @37, They may be correct, but you are assuming that there is no work in progress to apply similar finger printing techniques that found an AGW signal in the 2003 European heatwave. Also, you seem to be dismissing (or at least ignoring) Trenberth's critique of the Dole et al. paper. Good science takes time, give the scientists some time to look at this case properly. I expect that some more papers will be appearing in the literature sometime this year or early next year. Harry @36, I see that you have been doing the rounds reading the gossip on the internet--while you may find the errant prediction regarding the numbers of climate refugees amusing (the prediction it seems was made by environmental scientist Norman Myers), I assure you that those being directly affecting with the increasing frequency of extreme events vehemently disagree. I will be quite honest, these kind of predictions make me uneasy-- it is far to easy for contrarians and those in denial about AGW to cite these misguided calculations as evidence that AGW is exaggerated or to label people concerned about AGW as "alarmist". With that said, I do not believe that prediction was cited in WGII or AR4. Let me guess, you are typing your posts from somewhere in the developed world and not the flood affected region of Pakistan. Easy to make glib and smug comments from the comfort of one's cosy, dry and secure home with plenty of food-- unfortunately, that is not the reality facing those affected by extreme events, extreme events that are increasing as the planet warms. Go here, and click on "6 Billion Others". Casveat-- anecdotal evidence I know, but their experiences are consistent with what the science and observations are finding, not to mention Munich Re. Also, "Among dozens of climate facts and figures, the report shows that the number of people in Latin America and the Caribbean affected by extreme temperatures, forest fires, droughts, storms and floods grew from 5 million in the 1970s to more than 40 million from 2000 to 2009. Overall, adverse weather conditions have cost the region more than US$40 billion in the last ten years. For Mexico the estimated annual cost of dealing with the effects of climate change will be 6.22% of current GDP net present value by 2100 . Such costs will intensify budget constraints across Latin America and the Caribbean and may complicate attempts to reduce poverty and to meet the Millennium Development Goals." [Source] Predicting the number of people that are affected by AGW and that will be affected by AGW is incredibly tough, and that prediction by Myers was clearly very wrong, but that doesn't mean every forecast related to AGW is now wrong, nor does it mean that no-one will be negatively or that no-one has been negatively affected by AGW-- besides, this is still quite early days in our stupid experiment. What is your prediction Harry-- how many people do you think will die or have died or negatively affected as a result of AGW? How many refugees do you expect there will be come 2050? Even if, in the end, only say 1% of the current projection (i.e., 2 million) are affected, that is 2 million too many in my opinion. We have been warned, we know that we are a major contributing factor to this unraveling disaster that is playing out in slow motion.
  46. What was it like the last time CO2 levels were this high?
    Note to mods: Please notice that Gilles did in fact mostly succeed in his goal of wrecking this thread. More to the point, you helped him do it via your tolerance and catering (by responding extensively to his absurdities). There's much of interest about Pliocene climate that might have gotten discussed otherwise. I'm all in favor of free speech, but when the proverbial theater is on fire, shouts of "What smoke? If there is any smoke, you haven't proven it's from in here, that it's necessarily a result of fire, or that your hypothesized smoke and fire would be harmful!" (lather, rinse, repeat) are not only wholly counter-productive but boring. Put another way, this is a learning site, and people can't learn much in threads like this. My advice: Put Gilles in moderation and rigorously delete anything OT or trollish.
    Moderator Response: [DB] OK.
  47. A Convention for Persons Displaced by Climate Change
    Harry, I can't find that figure of 50 million. Can you provide a link? I found where UNEP identified 25 million already on the move, but I can't find a prediction of 50 million refugees by 2010.
  48. A Convention for Persons Displaced by Climate Change
    michael s #35: "It is too early to have scientific evidence for the Texas fires," The drought monitor is a good clue that something unusual is taking place: D4 = 'Exceptional' -- full size source
  49. Lindzen Illusion #1: We Should Have Seen More Warming
    The question to Lindzen, as to any expert, is "Exactly how much will you allow yourself to be wrong, and still be an expert?" Then make a neutral, peer-reviewed assessment of his statements/predictions, e.g. the mentioned 1989 version, and let him comment on it. As for the transient sensitivity, I think it is important to be careful about precise estimates of expected temperatures in a situation with considerable radiation imbalance. The temperature increase we experience now, about 0.15-0.17 deg/decade, is related mainly to the current CO2 level, and very little to the current increase. Even if we froze the level now, we should expect the temperature rise to decrease only slowly at first, with the temperature converging to something we could interpret as representing the transient climate sensitivity (TCS). Afterwards, in a "virtually constant temperature" situation we would, in the course of a few centuries, approach the temperature representing ECS. In a far-from-equilibrium situation, the "expected value right now", may not be very well defined. From the increase observed so far, I strongly suspect the TCS to be above 2 deg C, but that does not necessarily imply the ECS is >3. Of course, Lindzen should be pressed to state exactly what temperature observations would refute his claim of ca 1 deg sensitivity. Of course, he may do this conditionally, he just have to state the conditions as clearly, and they, too, must be easily testable. If he won't, his claim is a specualtion, not a testable hypothesis.
  50. More Carbon Dioxide is not necessarily good for plants.
    Why do you guys talk about weather eg euro heat wave as if its climate change? If that's true then the current temperature of the planet based on the UAH temperature record has not increased at all for the last 30 years.what I'm talking about is way closer to what the climate is than a local heat wave in europe.
    Moderator Response: [mc] See the extreme weather thread for discussion of heat waves.

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