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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 75551 to 75600:

  1. The human fingerprint in the daily cycle
    Norman#131: "During the day time, shortwave radiation dominates" This is merely an expression of daytime warming. Since the ground is increasing in temperature, it cannot be in equilibrium (radiated OLR and all other heat loss must be less than incoming solar). Hence you cannot automatically assume that OLR keeps up with apparent temperature. This is demonstrated for a number of different surface scenarios here. Example: During the day, copious solar radiation is absorbed at the surface, and the ground heats up rapidly. Initially, most of the heat is conducted down into the soil, but as the layer of warmed soil thickens, HS dominates; the heat is primarily transferred to the air. This is promoted by extreme differences (up to 28 K) between the ground temperature and the 2 m air temperature. At night, surface radiative cooling is balanced by an upward ground heat flux. Since the nocturnal boundary layer is very stable, the turbulent heat flux HS is negligible. In this example, HS is the 'upwards surface sensible heat flux.' The point is that greenhouse gases appear to slow the net transfer of the energy radiated from the ground back to space. Most of that transfer is taking place at night, because that is when the ground can cool. Added GHGs make that seem as if nights are warming faster than days - perhaps better put as 'nights aren't cooling as fast as they once did.' The upper of the two graphs from the paper shows a mean warming of 0.2C/decade across all hours; nighttime hours at twice this rate.
  2. Andrew Dessler's New Paper Debunks Both Roy Spencer And Richard Lindzen
    I think that this excellent essay by Stephan Lewandowsky titled "Climate sceptic science: read with caution" is relevant to this discussion. A teaser. "Ideology, subterfuge, and propaganda. That is all there is to climate denial."
  3. Andrew Dessler's New Paper Debunks Both Roy Spencer And Richard Lindzen
    Re Robert Murphy at 00:48 AM on 7 September, 2011 On the other hand, that's music to his fans' ears. He plays for his audience, of course. His book on "Economy" is another hint at that.
  4. Andrew Dessler's New Paper Debunks Both Roy Spencer And Richard Lindzen
    Sphaerica, your understanding matches mine, but remember that one of Spencer's goals in the paper is to show that climate models do not match observations, specifically that the underestimate the radiative gain from a temperature change from ENSO. He can't really use another climate model to prove that some other climate model is different (more or less a tautology). Albatross, I'm going to have to refresh my memory on the conservation of energy issue. I think we agree that what Spencer says online is different from the paper, specifically his claims about sensitivity. Dessler in his paper makes no such claims either. Spencer's accusations are unsupported because nobody is supressing his scientific claims about sensitivity since his paper has none and it was not supressed anyway. Dikran your chess analogy is good, but keep in mind that Spencer's paper did not go out on any limbs that can be easily sawn off (he left that to his blog). In fact he can simply argue the dispute over model choices is more evidence that the models are wrong.
  5. Extreme Flooding In 2010-2011 Lowers Global Sea Level
    villabolo#7: "predictions date back to at least 1994" That's clearly a typo; we're told repeatedly that those models don't work. And if we've learned nothing else, we know enough to believe what we are told, not what we observe. Or at least that's what I've been told.
  6. Miriam O'Brien (Sou) at 02:48 AM on 7 September 2011
    Andrew Dessler's New Paper Debunks Both Roy Spencer And Richard Lindzen
    Here's a video by Dessler on his 2011 GRL paper and debunking of Lindzen and Spencer. Really good of him to do a video for the general public.
  7. NASA Satellites Detect Pothole on Road to Higher Seas
    Sphaerica, When a new theory or explanation arises, the burden of proof usually rests on the shoulders of those who present the new explanation, not on the existing theory. To request a citation for something that is basic to the understanding of ENSO led me to conclude that you were not well versed in the subject. Forgive me if I have misrepresented your knowledge base here. As Rob stated in #25, this may alter the existing thinking, but the onus is still on the new presenters to prove their case in order to convince the status quo. One peer-reviewed paper will not upset the apple cart, but it may lead to re-analysis of the current thinking, and further research.
  8. Andrew Dessler's New Paper Debunks Both Roy Spencer And Richard Lindzen
    Realclimate has posted a link to a version of the paper at Desslers uni page: http://geotest.tamu.edu/userfiles/216/Dessler2011.pdf
  9. NASA Satellites Detect Pothole on Road to Higher Seas
    24, Jonathon,
    You really need to read up on ENSO events before commenting as such.
    Spare me the arrogance. I understand ENSO more than well enough. I asked twice for your citation, a paper I had not seen or been able to find when I looked. Was it so difficult to simply provide that on the first request, or even the second but without the unnecessary hubris?
  10. NASA Satellites Detect Pothole on Road to Higher Seas
    Jonathan - please re-read the post, you appear to missing important details. Such as: "So what's up with the down seas, and what does it mean? Climate scientist Josh Willis of NASA's Jet Propulsion Laboratory, Pasadena, Calif., says you can blame it on the cycle of El Niño and La Niña in the Pacific......................"But El Niño and La Niña always take us on a rainfall rollercoaster, and in years like this they give us sea-level whiplash." This is a re-post of a NASA JPL article, based on material provided by Josh Willis and Steve Nerem, both world experts on the topic of sea level. The temporary exchanges of water between the oceans and continents is now able to be observed using the GRACE gravity satellites - a recent development. See the sister SkS post, highlighted in the green box at the bottom of this post, for further discussion. Don't be surprised if climate scientists modify their views in the light of new observations and measurements. That's how progress is made. I may have the wrong end of the stick, but I assume Carmen Boening's results will appear in the peer-reviewed literature in due course.
  11. On Mowing a Virginia Lawn … And Contemplating a Greenland Iceberg
    People on this site should also read this article Gobsmacking Greenland Glacier Loss Alarming, genuinely, not simply "alarmist". :(
  12. Andrew Dessler's New Paper Debunks Both Roy Spencer And Richard Lindzen
    Dana@14 "short-term temperature changes are dominated by ocean heat transport, not cloud cover changes. " What do you mean by short-term exactly? People tend to think of the oceans changing temperature relatively slowly, so one should be clear about the time scale involved and what is causing the ocean to change on that time scale. I know this is alluded to in the post a few times, but the point must be clear that we are effectively talking about changes brought about by ENSO, no? My concern now is that some people might misinterpret, spin this to claim that ENSO is driving global warming.... I like this part from the body post, "Dessler finds that.... In fact, the heating of the climate system through ocean heat transport is approximately 20 times larger than the change in top of the atmosphere (TOA) energy flux due to cloud cover changes. Lindzen and Choi assumed the ratio was close to 2, while Spencer and Braswell assumed it was close to 0.5." Let me see, should we go with "found using observations" or with the "assumptions" of ideologically driven scientists? ;)
  13. Andrew Dessler's New Paper Debunks Both Roy Spencer And Richard Lindzen
    Eric @11, S&B postulated that clouds caused some of the ENSO temperature changes, not ENSO itself Actually, that is not clear Eric, b/c what Spencer is trying to argue is not clear. If you follow his online discussion (sorry, I cannot recall exactly where that was held off the top of my head, but I did find this), Roy's reasoning was almost incoherent and at times his statements are inconsistent. We know that clouds, especially deep convection, respond to the change sin surface winds and SSTs associated with ENSO, and those changes in cloud cover probably have some feedback. And no comment from you Eric about the problems with Spencer and Lindzen's and Braswell's and Choi's thinking running into trouble with the conservation of energy. "Their real conclusion is that it is not simple to extract cloud feedback (or even the sign) from temperature changes the way that the models are claimed to do. " That may be, but that is most definitely not even close to how their findings have been spun and distorted, not only by the denial misinformation machine, but by Roy Spencer himself. I have said this elsewhere on SkS, and it still applies today (especially after Spencer has now made a rather brazen defamation attempt on Dessler noted by Sphaerica @9): "Spencer is now clearly using science as a political tool in his ideological and political vendetta against the IPCC and climate scientists who are rightly concerned about the impacts of us doubling (or even quadrupling CO2). I find that incredibly disturbing." Spencer's actions of late also make his claims about being interested in advancing the science ring hollow. Eric you noted on another thread that: "With such gross oversimplifications on both sides I can't help but think Spencer is arguing about nothing." Yes, on that we agree.
  14. Dikran Marsupial at 01:41 AM on 7 September 2011
    Andrew Dessler's New Paper Debunks Both Roy Spencer And Richard Lindzen
    When a good chess player plays chess, instead of playing the move that maximises his advantage, he plays the move that minimises his opponents maximum advantage; on other words he plays in the expectation of best play from his opponent. A good scientist publishes his arguments in the same manner; instead of presenting the strongest argument he feels the evidence can support, he presents the strongest argument that an opponent can't refute. So if there are choices to be made in presenting the evidence, you don't make the choices that maximally support your argument, you make the choices that give the least support for your position. If you are right, the evidence should still be on your side even then, and you will have made your paper bullettproof. Roy clearly didn't do that here, he didn't choose the models that were most closely in accord with the data, but those that would clearly make his argument. As it happens those models also happen to be amongst the worst in terms of matching the observations. What he should have done is present the results for all of the models (so there can be no accusation of cherry picking) and then find out why some of the models fit the observations better than others. Unfortunately for him it appears that it is not climate sensitivity. If his scientific career were a game of chess, this move would be annotated with a "?!" at best.
  15. Miriam O'Brien (Sou) at 01:40 AM on 7 September 2011
    Andrew Dessler's New Paper Debunks Both Roy Spencer And Richard Lindzen
    Andrew Dessler has made his paper available here.
  16. Andrew Dessler's New Paper Debunks Both Roy Spencer And Richard Lindzen
    Eric, there are a few key findings in this paper. One is that the heating of the climate system through ocean transport is ~20 times larger than energy changes due to cloud changes. A second is that while cloud changes can lead surface temperature changes, that's a result found in climate models as well, in which surface temperatures are an input. We'll have a bit more on this tomorrow. The bottom line is that contrary to Spencer and Lindzen's claims, the climate is behaving as models expect, and short-term temperature changes are dominated by ocean heat transport, not cloud cover changes.
  17. NASA Satellites Detect Pothole on Road to Higher Seas
    Sphaerica, You really need to read up on ENSO events before commenting as such. The following are a few good links which show the SLR dependence on ENSO events. By the way, I did read the original post, which is why I am commenting. Rob appears to be disputing years of evidence to the contrary. I would suggest that the onus is upon him to provide significant evidence beside the graphic above. While it is possible that the changes in rainfall between EL Nino and La Nina conditions does lead to greater changes in SLR, it is the exception, not the rule to the current thinking. http://www.agu.org/pubs/crossref/1999/1999GL002311.shtml http://www.aviso.oceanobs.com/fileadmin/documents/OSTST/2004/lombard.pdf http://www.legos.obs-mip.fr/fr/equipes/gohs/pdf/lombard.pdf
  18. Andrew Dessler's New Paper Debunks Both Roy Spencer And Richard Lindzen
    8, Eric (skeptic), Your post confuses me. On clouds, Dessler showed that their effect, one way or another, is trivial, so your proposed question of "are clouds forced by ENSO or a feedback from temperature change" is moot. On ENSO, I don't at all see what your problem is. My understanding is that Spencer tried to treat ENSO events as climate change (temperature changes) in and of themselves, without reference to the mechanics that cause them. By ignoring those mechanics, he makes them seem like unrelated climate events controlled by clouds or other factors. To get better results in his claims about models, he also ignored those models that best handle ENSO events. Lindzen did something similar, by treating annual swings in temperature that are caused by a local physical mechanism (ENSO) as if those were actual changes in the heat content of the earth-energy system over longer time scales. You just can't do that. It would be like rocking a parked car, and then claiming you can use that behavior to model how the car would accelerate away with the engine on and a driver behind the wheel.
  19. Andrew Dessler's New Paper Debunks Both Roy Spencer And Richard Lindzen
    "...if what they find happens to disagree with Al Gore..." Spencer *has* to know that no climate scientist gives a rat's posterior about what Al Gore says about the science. This is gutter-level denialism.
  20. Andrew Dessler's New Paper Debunks Both Roy Spencer And Richard Lindzen
    S&B postulated that clouds caused some of the ENSO temperature changes, not ENSO itself. Extending that to "climate change" is unsupported, also they did not quantify the amount of temperature change that was radiatively forced except very roughly (70/30). Their real conclusion is that it is not simple to extract cloud feedback (or even the sign) from temperature changes the way that the models are claimed to do.
  21. Andrew Dessler's New Paper Debunks Both Roy Spencer And Richard Lindzen
    Eric(skeptic) @ 8: that may be the question you would like answered, but it's definitely not the question that S&B11 was trying to answer, which was more like: are clouds causing ENSO (and any and all climate change)? Dessler seems to answer that question strongly in the negative.
  22. Andrew Dessler's New Paper Debunks Both Roy Spencer And Richard Lindzen
    An interesting two pronged attack by Spencer on his blog. First, a post preempting everything that re-iterates how wonderful and indisputable he considers his own paper to be, and how nefarious must be the nature of his critics. Second, today, a post on a completely different subject, but apparently aimed at undermining Dessler's credibility. What I found most comical was the following quote from his first of the two posts, on the brouhaha over his own paper, where he in one breath says that funding by Big Oil is an urban legend, but then goes to accuse other scientists of fudging their own work to gain government funding. I swear, he just Poe'd himself.
    And (BTW) we get no funding from Big Oil or other private energy interests. Another urban legend. I hate to say it, but we need some sharper tools in our shed than we have right now. And the fresh eyes we need cannot have the threat of a loss of government funding hanging over their heads if what they find happens to disagree with Al Gore, James Hansen, et al.
  23. Andrew Dessler's New Paper Debunks Both Roy Spencer And Richard Lindzen
    Dessler essentially admits they aren't measuring sensitivity, but ENSO. Dessler picked some models that do better modelling ENSO yet none of them drop into negative correlation. Understandable since models can't easily predict the pos/neg or neg/pos switch. So what we end up with is "And since most of the climate variations over this period were due to ENSO, this suggests that the ability to reproduce ENSO is what's being tested here, not anything directly related to climate sensitivity." Dessler then tries to unglue himself from the failure of linear regression, lagged or not, by pointing out that temperature response controls ENSO which controls temperature. Thus, he states, "clouds did not cause significant climate change over the last decade" But the question we are trying to answer is are clouds forced by ENSO or a feedback from temperature change (i.e. climate change from CO2 forcing), and if feedback, what sign? The answer from S&B11 is we don't know. Dessler does not answer that question either.
  24. NASA Satellites Detect Pothole on Road to Higher Seas
    22, Jonathon, As I said, however, thermal expansion affects the upper 700 meters. ENSO events affect the upper meters. The amount of actual mixing in those upper meters is even less. In any event there is no net change in heat content, just a redistribution. I do not see how any effects can be more than trivial. Please provide a citation for your claims. As far as sea level rise actually associated with ENSO events... did you even read the post on which you are supposed to be commenting? The cause is the excessive precipitation falling on land (Australia, the northern coast of South America) instead of open ocean. It is not due to thermal expansion. I shouldn't need to say this. Please read the original post. If you wish to dispute it, provide a solid argument to do so, backed by data, calculations and most importantly citations.
  25. Miriam O'Brien (Sou) at 00:08 AM on 7 September 2011
    Andrew Dessler's New Paper Debunks Both Roy Spencer And Richard Lindzen
    Thanks, Rob and Dana for this outline of Dessler's paper. Good to have. BTW - I just popped over to Spencer's blog. From what I gather he is saying in his latest blog article is that to claim global warming will make droughts and floods worse than they would otherwise have been is a load of hooey. And this man is supposed to be helping research climate? I suppose he has tenure, but surely that sort of scientific illiteracy would be grounds for a shift sideways to a clerical or TA role, if not the sack.
  26. Andrew Dessler's New Paper Debunks Both Roy Spencer And Richard Lindzen
    The Spencer paper compares a 100 year model run against 10 year top of the atmosphere measurements, would I be correct in thinking that that 10 years would be influnced by sulphate areosols, methane and CFC levels, by the ENSO which may not come out as neuteral over 10 years and due to dropping solar forcing (although I am not sure about the latter as if it is a TOA measurement it should measure incoming shortwave light).
  27. NASA Satellites Detect Pothole on Road to Higher Seas
    Sphaerica, I already mentioned the local effects of La Nina / El Nino. Yes, the volume affected is only the upper ocean. The deeper ocean has a fairly constant temperature and density, which is unchanged by this surface movement. While the depth is small, the area is large, equating to a volume which is not insignificant as you claim. While you feel that sea level should rise during a La Nina and fall during an El Nino, would you care to give your explanation as to why we are seing the reverse effect as shown in the above graphic. El Nino would be expected to result in less enery loss due to the decrease in the trade winds, hence warming.
  28. Andrew Dessler's New Paper Debunks Both Roy Spencer And Richard Lindzen
    I can't wait to see what drroyspencer.com has to say about this.
  29. Venus doesn't have a runaway greenhouse effect
    Aye, Bob--good grief, when I first came to the climate situation a few years ago, I knew that complaints about the use of "greenhouse" were misplaced, because it was actually stratospheric CO2 radiating heat to the surface. Sigh . . . well, live and learn, and whenever an absolute pops into the head, beat it with a hammer until it breaks down into mere probability.
  30. NASA Satellites Detect Pothole on Road to Higher Seas
    19, Jonathon, I don't believe your statement here is accurate. Any citations that you can provide for that position would be welcome. First, El Nino doesn't actually change the energy content of the ocean except in the reverse fashion that it appears; an El Nino causes a more rapid loss in energy/temperature, while a La Nina enables it to absorb more, so the effects should be reversed. Based on this, sea levels should actually rise due to a La Nina, and drop due to an El Nino. Secondly, the "piling up" of water that occurs does not reach far down at all (considering the upper layer of the ocean is usually taken to mean the upper 700 meters), so the volume of water actually affected by the shift from one event to another is really very small. The overall global affect due to his shift would be minor. Certainly, there are local changes in sea level, in that is part and parcel of the mechanics behind ENSO events. But I don't believe there is any known or presumed global mean sea level change that results from ENSO events due to thermal expansion. I've certainly never seen mention of it until this post, but as stated, the change is a result of where precipitation falls, not thermal expansion. Also, your statements about precipitation changes are too broad. It all depends on where you live and what the season is. El Nino (and La Nina) will make some areas wetter, some drier.
  31. Journal editor resigns over 'fundamentally flawed' paper by Roy Spencer
    @Camburn #47: When you re-read S&B be sure to take into account the humongous error bars associated with it.
  32. Venus doesn't have a runaway greenhouse effect
    96, Rosco,
    ...although why we need to simplify insolation to a constant irradiated disk when we have computer programs which ought to deal with the complex equations seems unnecessary.
    This is exactly true, in that many computer models, which run on super computers and take months to churn through a hundred years of simulation, do in fact do things at that level. The Stefan-Boltzman, disk/area approximation is purely a very simple model for 50,000 foot arguments (meaning, for introductory teaching, trivial blog discussions and explanations like this one). There's an important lesson to be learned there. Everything that is discussed is a simplification of what is really going on (to make it manageable by human minds, or in discussions). In particular, when people get around to "visualizing" the actual interactions of the greenhouse effect they get it all wrong. They try to picture simple "back radiation" and other things that are useful gross oversimplifications in some situations, but are really totally and completely wrong. When you find something that doesn't look right, dig deeper! The answer lies in the as yet unknown complexity, not in the idea that thousands of scientists over hundreds of years have made some obvious, stupid blunder.
    I still have doubts about the relevance to the surface temperature but that can wait till another day.
    That's fine. Keep learning. But really... all of this discussion belongs on another thread. In the future, please be more attentive to the appropriate discussion for the thread in question. Feel free to find a better thread, and leave behind a comment explaining where you've posted your question (although many of us will find it anyway by looking at the "recent comments" page of this site). I'm glad you've come to some terms with the factor of 4 aspect of the equations and can now move ahead.
  33. Andrew Dessler's New Paper Debunks Both Roy Spencer And Richard Lindzen
    @dorlomin #2: As Big Tobacco proved, all the anti-AGW Spin Machine needs to do is create doubt and confusion within the general public in order to prevent government from taking action to address a problem.
  34. Andrew Dessler's New Paper Debunks Both Roy Spencer And Richard Lindzen
    A copy of the paper is apparently available here.
  35. OA not OK part 4: The f-word: pH
    Doug do you have a reference for this? average ocean pH has decreased by 0.11 pH units (from 8.25 to 8.14) since the industrial revolution and is on track to decrease by a further 0.3 units Thank you Tony
  36. Andrew Dessler's New Paper Debunks Both Roy Spencer And Richard Lindzen
    Instead of converging the public debate is still increasingly polarised.
  37. Andrew Dessler's New Paper Debunks Both Roy Spencer And Richard Lindzen
    No wonder the Spencer fanclub consists nearly entirely of people who have no idea what his explanations mean, but loves his conclusions. No wonder his reader is more like a Glenn Beck spectator, and not a physics student.
  38. NASA Satellites Detect Pothole on Road to Higher Seas
    Dave, Compare the surface water temperatures changes in 2008 and 2011 with the SLR graph above. The generally warmer waters from 2003 - 2007 can also be seen. http://1.bp.blogspot.com/-gyjdmjk0b3I/Thl79Kxnb4I/AAAAAAAAGio/EoxXdfvFLgs/s1600/AMSRE_SST_2002_thru_July_7_2011.gif
  39. NASA Satellites Detect Pothole on Road to Higher Seas
    enSKog, Actually, La Nina tends to amplifier the normal state by increasing the trade winds and forcing more warm water towards the Western Pacific. EL Nino is a reverse, whereby the warm Pacific waters are pushed eastward towards South America. These warmer waters atop colder actually induces greater mixing in the eastern Pacific. While local conditions vary, El Nino years lead to have warmer, drier seasons, while La Nina years lead to cooler and wetter. Whether La Nina leads to lower SLR due to cooling of the ocean water or greater precipitation (or both) has not been accurately determined. Since thermal expansion of the oceans is only occurring in the upper portion (the deep ocean has a fairly constant temperature), the El Nino / La Nina cycle can greatly impact this contribution. Claims of changes in SLR should be viewed with respect to ENSO changes in the same way that temperature changes should. Compare the SLR and temperature records for the El Nino of 1998 and the La Nina of 2011.
  40. NASA Satellites Detect Pothole on Road to Higher Seas
    Question- given the huge amount of water moved, shouldn't we see a signal in the surface water temperatures? Did I miss a discussion of this?
  41. Extreme Flooding In 2010-2011 Lowers Global Sea Level
    muoncounter: "But it looks like some folks were predicting heavier rain and more snow back in 2006." Muon, It seems that those predictions date back to at least 1994. http://resources.metapress.com/pdf-preview.axd?code=w7q445p545h78g38&size=largest A. M. Fowler, and K. J. Hennessy 23 June 1994 "It is now widely recognised that the most significant impacts of global warming are likely to be experienced through changes in the frequency of extreme events, including flooding. This paper reviews physical and empirical arguments which suggest that global warming may result in a more intense hydrological cycle, with an associated increase in the frequency and/or magnitude of heavy precipitation. Results derived from enhanced-greenhouse experiments using global climate models (GCMs) are shown to be consistent with these physical and empirical arguments. Detailed analysis of output from three GCMs indicates the possibility of substantial increases in the frequency and magnitude of extreme daily precipitation, with amplification of the effect as the return period increases."
  42. Venus doesn't have a runaway greenhouse effect
    I always had a problem with the factor of 4 thingie being used to reduce insolation. I have actually learnt some things from this discussion. And, whilst I am a sceptic I wasn't always and I really do not have an agenda. The equation always caused me to question. Whilst I could appreciate that it seemed right by all the science I had ever read it still seemed at odds with calculating the effective temperature of earth - heck I know I never bought it. But if I look at as a radiative balance statement- that to maintain radiative balance for earth the OLR over the surface of a sphere only has to be one quarter of the insolation over the disk - well heck that makes some sense - although why we need to simplify insolation to a constant irradiated disk when we have computer programs which ought to deal with the complex equations seems unnecessary. So we have some common ground - there is an area where the insolation is balanced by the OLR and the temperature of this "interface" - for lack of a better word at the moment - is ~255 K or -18 C. I still think all of this discussion has been relevant and there is still some way to go. I still have doubts about the relevance to the surface temperature but that can wait till another day.
  43. Venus doesn't have a runaway greenhouse effect
    Rosco @94, the level of the atmosphere with a temperature of 255 degrees K is on average approximately 5 km, and if the GHG in the atmosphere absorbed and emitted equally at all wavelengths, it would radiate approximately 240 W/m^2 at that level. But in fact the GHG's only radiate at a limited number of wavelengths, so much of the radiation comes from the much warmer surface. Consequently the it is only when you get to the TOA that the sum of energies across all wavelengths of outgoing radiation sums to ~240 W/m^2.
  44. Venus doesn't have a runaway greenhouse effect
    But isn't the area of the atmosphere radiating ~240 W/sq m actually at ~5 km above the Earth's surface?
  45. The human fingerprint in the daily cycle
    131, Norman, If you look at any solar spectrum curve... You see that the most energy comes in at short wave lengths (visible light). During the day this "dominates" because it so outweighs any down-welling IR in any calculations. At night, there is no such incoming shortwave radiation. Infrared radiation dominates. This isn't about "up-welling" at all. It's about what is coming back in to keep the surface warm... short wave sunlight during the day, long wave IR from greenhouse gases at night.
  46. Venus doesn't have a runaway greenhouse effect
    Rosco @91: The equation you misquote applies only for surfaces with no variation in temperature, and with an emissivity of 1. Neither is true of the Earth. In particular, the effective emissivity of the Surface of the Earth significantly less than 1 due to the effects of the Greenhouse gases in the atmosphere. In contrast, the effective brightness temperature of the Earth as observed from space has, by definition, an emissivity of 1. Therefore, for planets with greenhouse gases, this equation only applies at the Top of the Atmosphere. Further, the Earth does not have equal temperatures across the globe, but it has near equal temperatures - sufficiently close that this equation represents a fair approximation. So, let's check out the approximation at the TOA for the Earth. According to NASA, the Black Body temperature of the Earth as observed from space (aka, the brightness temperature) is 254.3, and the radius of the Earth is 6378100 meters. Therefore the total energy radiated to space by the Earth is approximately: 5.6704*10^-8 * 254.3^4 * 4 * pi * 6378100^2 = 1.2122 * 10^17 Watts The TSI equals 1366 Watts/m^2, and the Bond albedo equals 0.306 so the total energy absorbed by the Earth is approximately: 1366 * (1 - 0.0306) * pi * 6378100^2 = 1.2116 *10^17 Watts. That is just a 0.06% difference. Not bad for an approximation. Of course, I understand that you have been so blinded by your need for AGW to be wrong that you will not be able to acknowledge this clear result. Consequently, I suggest you do as climate scientists do and ignore the approximation. Instead, work out the total energy absorbed from the sun using in each cell of a 5 degree latitude by 5 degree longitude cell of the Earth's surface over a one year period. Remember to compensate for the different areas of each cell depending on their latitude. Sum the total energy absorbed. Then determine the total energy emitted from each cell over the year based on the variation of temperature and surface type (which effects emissivity), and sum the results. If you are correct, the sums should be approximately equal. But in fact they will not be, for as has been shown in the General Circulation Models the equality is at the top of the atmosphere, not the surface. IF you are going to dispute the climate scientists who have gone to the effort of just that sort of detailed calculation (and much more), you should yourself make that same level of detailed calculation instead of disputing an approximation used for teaching purposes (as you have been doing).
  47. Venus doesn't have a runaway greenhouse effect
    91, Rosco, This goes back to the problem you were having with the geometry. The energy absorbed is proportional to S(1-r) over the area of a disk. The energy emitted is the same, but it is distributed over 4 times the area because the earth is a sphere and not a flat disk. Perhaps this discussion will make it more clear, but really it comes down to two simple statements: The earth absorbs energy as a disk (πr2). The earth emits energy as a sphere (4πr2). The temperature of the earth reflects this, which is why we divide 1368 by 4 to get 342, which in turn is cut to 240 by the earth's albedo (1-r).
  48. The human fingerprint in the daily cycle
    muoncounter @ 130 I looked at the Malamud paper you linked to. I do not understand this statement from the article: "Our basic hypothesis is that a large part of the temperature and DTR trends at Mauna Loa can be attributed to changes in CO2. At night, longwave radiation and turbulent sensible heat fluxes dominate heat loss. Increasing presence of greenhouse gases will result in enhanced reradiation back towards the surface and hence warming nocturnal temperatures. During the day time, shortwave radiation dominates, particularly in tropical regions." This is my most basic question and the article does not really answer it. What is the meaning of "shortwave radiation dominates"? Shortwave solar energy will have a greater watts/meter flux than upwelling IR but the surface emitted IR will still be greater during the day than at night. Unless shortwave radiation pressure can limit the upwelling IR raditation from being emitted, how does the dominance of shortwave radiation affect the upwelling shortwave radiation (from my physics knowledge, the IR emission is determined by the temperature of the object and its emissivity). During the day you will have greater flux of upwelling IR from the surface than at night because of the greater temperature of the surface. You should have a stronger reradiation during the day than at night, hence more effective GHE (more IR going up during daytime, more coming back down from the omnidirectional energy distribution of greenhouse gasses).
  49. Journal editor resigns over 'fundamentally flawed' paper by Roy Spencer
    Sphaerica: Sorry you couln't watch Dr. North's presentation. It was quit good. The question period was excellent, with both Dr. Lindzen and Dr. North commenting. I seldom do watch video's, as I agree with you. Reading is a lottttt faster, and you can easily go back to re-digest what you have read. I just re-read Dr. Trenbeth's and other two fellows op ed piece. The very tone raised red flags to me, so I feel I must go back and re-read S&B. There may be more value to S&B than my original readings brought to me. Now it will be to find the time.
  50. Venus doesn't have a runaway greenhouse effect
    http://www.atmos.ucla.edu/~liougst/Lecture/Lecture_3.pdf Radiative Equilibrium Energy Conservation Principle at the top of the atmosphere (TOA) Incoming solar energy absorbed = Outgoing infrared energy emitted S (1 – r) x π ae2 = σTe4 x 4 π ae2 σ = Stefan-Boltzmann constant S = Solar constant (total solar energy/time/area at TOA) r = Global albedo ≅ 0.3 ae = Radius of the Earth Te = Equilibrium temperature of the Earth-atmosphere-system Leading to Te = ∜(S(1-r)/4σ) But if we restate the “equality” Incoming solar energy absorbed = Outgoing infrared energy emitted S (1 – r) x π ae2 = Ro x 4 π ae2 (where Ro = σTe4 is the outgoing radiation) we see that this simply says that the outgoing radiation is a quarter of the incoming radiation. Alternatively, taking the original “equality” and dividing both sides by π ae2 you arrive at the interesting postulation that :- S (1 – r) = σTe4 x 4 and thus proving the Stefan-Boltzman equation is wrong. So what has gone wrong here? Clearly the original statement is not an equality !

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