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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 102201 to 102250:

  1. Renewable Baseload Energy
    Rob@351: 1. I do think the electric populsion of masses is going to happen. That is not very far away. Utilities are already planning how to sell more electricity. 2. Most of the "power up" is going to happen in the late night, early morning. 3. That in itself will require a more constant source of power. I agree, we need to do everything we can to limit the use of fossil fuels. They are a finite resource and should be used ONLY when necessary. It is obvious that solar is in its infancy. Nuclear is a mature energy source. Yes, in the US we have lots of NIMBY folks. We have fallen behind the rest of the world in thinking it seems as the rest of the world is building and planning to build 150 nuclear power stations. We are at one presently. Pretty dumb isn't it? http://www.world-nuclear.org/info/inf17.html
  2. 2nd law of thermodynamics contradicts greenhouse theory
    OK. So, damorbel recently wrote this gem: The wavelenth difference is indeed great but what that count for? Sure it indicates that the Sun/Earth system is in considerable disequilibrium. But the only significance of this is the nature of the disequilibrium, which is precisely what we are talking about, the contradiction of AGW/GHE 'science' and the 2nd Law of thermodynamics, exactly the OP topic of this thread. Now, he/she tries to explain it, but the only explanation is: (1) The difference in the wavelengths of radiation emitted by the sun vs. by the earth means that the sun and the earth are not at the same temperature. (2) This temperature difference means that heat will flow from one to the other. It should be obvious that this contributes nothing whatsoever of value. None of this justifies damorbel's nonsensical claim that planetary albedo is irrelevant to temperature ... and none of it has anything to do with AGW, let alone proving a "contradiction" between AGW and the 2nd law of thermodynamics. Damorbel, did you ever read the last paragraph of this comment? Did you understand it? I'd also note that damorbel has still not explained why he/she approvingly cites an explanation at wikipedia that explicitly relies on the exact same mechanism that he/she thinks violates the 2nd law of thermodynamics.
  3. The human fingerprint in the seasons
    I don't know enough geology to produce heat content measurements for land, though I have seen heat content papers of the oceans. However, it struck me that NH versus SH should be similar if I were right about the heat content at depth. So, I tweaked my graph. No disrespect to Muoncounter, but I'm not sure which three samples 'mean:3' is applied to at WoodForTrees; so, I stuck with my first method for now. Besides, as much data is being aggregated already, I doubt that the additional months will change the shape much. Sea Surface Temperature Anamolies 2x2 of NH-SH, January-July It isn't exactly what I was expecting. Instead of NH and SH being very similar, instead, the SH is showing more disparity between winter and summer warming than the NH is. I wonder if I'm just seeing a random correlation or if there is a physical reason for this difference. I'd hazard a guess that it might have something to do with the north pole being in the middle of an ocean and the south pole being in the middle of a continent. Tom Curtis, Continuing... To use a loose analogy, if there is a body being heated by some relatively constant energy source, and you cover it with a blanket, until a new equilibrium temperature is reached, the blanket will be cooler and radiate less energy than the body used to. But, after a new equilibrium is reached, it will radiate exactly the same. Of course, the body will be warmer.
  4. The human fingerprint in the seasons
    actually thoughtfull @65 I still think you are missing HR's point. If you need to invoke TSI measurements then this work does not supply new independent evidence for an increased GHE, because you are reliant on the TSI measurements to interpret the results "correctly". I'm no expert in this field but it seems to me that Michael Sweet @24 had a good point: Given the short lifetime of Water Vapour in the atmosphere then surely it responds to the changing local solar irradiance, but not to heat "trapped" by CO2. Given that, it seems that this work is more convincing the Nighttime/Daytime argument when WV has less time to respond.
  5. Spaceman Spiff at 10:03 AM on 5 December 2010
    Stratospheric Cooling and Tropospheric Warming
    Sphaerica at 03:12 AM on 5 December, 2010: You said: "So CO2 prevents energy from escaping from the troposphere into the stratosphere in the CO2-IR bandwidth, and CO2 actively cools the stratosphere by emitting energy in the CO2-IR bandwidth." This is not correct. CO2 within the troposphere is responsible for emitting most of the light within the 13.5-17 micron CO2 band. This light (except for the sharp spike right near 15 microns) emerges from somewhere within the mid and upper troposphere, where the gas is just becoming optically thin to those transitions. This is what is meant by a "photosphere". The light of stronger transitions (near the bottom of the CO2 spectral feature) will emerge higher up in the troposphere (where the density is lower and the remaining path length out is shorter), where the T is lower and so the thermal emission is weaker. The light of weaker transitions emerges from deeper within the troposphere, where T is higher and thus the thermal emission is greater (the walls of the CO2 spectral feature). Have a look at the figure (from RealClimate) I posted in #126: CO2 absorption strength vs. wavelength. Nearly all of this radiative energy passes through the stratosphere, with the exception of the very strongest transitions lying very near to 15 microns (the sharp spike in the figure I linked to, and visible by running a default radiative model from Archer's website). The photosphere for these transitions lies in the stratosphere, where T is higher and thus so is the emission intensity.
  6. The human fingerprint in the seasons
    So Tom (#54), Convection is a result of lower air holding more energy (or being warmer, and thus relatively less dense on a curve described by atmospheric density driven by gravity and PV=nRT) than the air above it; where does this energy come from if not radiated or conducted from the surface? Convection is a movement of matter, not really a transfer of energy from some matter to some other matter. Flippancy aside, I see your point that the stratosphere will radiate more with more CO2, but it is also true that the troposphere will absorb more with more of any GHG. If it absorbs more, it will also be warmer and radiate more. What I've read leads me to believe that stratospheric cooling has more to do with the radiative imbalance that the earth is currently in. Mouncounter, Thanks! Don't mind at all, wouldn't have posted what I had if I wasn't looking for some other ways of doing it. Thinking more on the difference between the degree of warming of the NH compared to the SH. I would hazard a guess that it has something to do with the NH having a lot more land surface than the SH. Heat at the surface of the ocean gets distributed downward a lot more readily than heat at the surface of land. So, you'd want to look more at heat content down to some depth than surface temperatures.
  7. Stratospheric Cooling and Tropospheric Warming
    Bob Guercio at 08:51 Yes, its one of those subjects that takes a bit o nutting out... but then it all becomes clear, and the T profiles vrs altitude suddenly make sense. It was something that took me many hours to fully "get". (thanks to science o doom, and Ramanthan and Dickinson)
  8. 2009-2010 winter saw record cold spells
    #14: "become an annual skeptic talking point. " It already has. Try searching 'coldest November in living memory'. But here is some interesting anecdotal perspective on historic winters in the UK.
  9. 2nd law of thermodynamics contradicts greenhouse theory
    No, damorbel, you are incorrect that "the total scattering depends only on the amount of scattering material." Scattering does depend on frequency of the radiation and the size of the reflecting matter. But your obsession with scattering is not relevant to absorption, which is the problematic behavior of greenhouse gases. Just to get you off of your reflection obsession, let's assume that you are correct that the same amount of radiation emitted by the atmosphere, water, and land toward space are reflected back, as the amount of radiation coming from the Sun that is reflected by all those. As that emitted radiation is on its way toward space, before it is reflected back down, some of it is absorbed by greenhouse gases. The absorbed radiation's energy can't be reflected, because it's not in the form of radiation any more. Only some of that energy immediately is turned back into radiation. So right there you've got a greenhouse gas trap of radiation and therefore a trap of energy, completely in addition to any reflection. Even if you were correct about reflection (you're not), the greenhouse gas absorption effect would exist, so increasing greenhouse gases would trap more energy.
  10. Stratospheric Cooling and Tropospheric Warming
    Joe, As I reread what you wrote, I realize that you were correct. I needed time to digest everything and put the pieces together. Thank you, Bob
  11. Stratospheric Cooling and Tropospheric Warming
    Bob Guercio @ 145 Yes... but the thing is with the denser atmosphere at lower altitudes, is that what is emitted by co2, is absorbed by co2, simply because there are more molecules per volume. As you rise in altitude, with the reducing pressure, the molecules absorb less and less of the emitted radiation of their neighbors. Just due to the distance/space between molecules. So at lower altitudes, even though a molecule at a warmer T is emitting more, its simply swapping energy with its neighbors. But once you reach the tropopause, the distance between molecules, means that more energy escapes than what is absorbed from its neighbors. I tried to explain the reason for this at 57. Collisional exchanges with a gas at radiative equilibrium, will mean that energy is being deposited into the n2, o2, when the co2 is a net radiator, the collisional exchange will work the other way, from the warmer n2 @ o2 to the cooler co2(because it is loosing energy through radiation.)
  12. The human fingerprint in the seasons
    #63: "either a solar or CO2 initial forcing will be accompanied by a strong H2O GHG positive feedback" The cause and effect of this mechanism seems a trifle thin and the story quickly becomes quite convoluted. a. If we postulate that once the initial solar or CO2 forcing gets a warming cycle started, do we then suggest that H2O feedback alone is sufficient to keep it going? Is H2O feedback sufficient to restart the warming system after a transient cooldown, such as a Pintatubo type event? b. If solar alone is the initial forcing, where is the record of that solar event? Have they happened in the past? Where are those records? c. How can CO2 be an 'initial forcing', when CO2 forcing continuously increases with the log of the CO2 concentration relative to 'pre-industrial'? Initially the ratio of CO2 to pre-industrial would be close to 1 and its log close to 0. d. If it is accepted that CO2 is the initial forcing, why is the same mechanism (CO2 forcing) not continuously doing the forcing? How does it get switched on and off? As I said, convoluted. It is stunning that some folks will accept these complicated schema when there is a far simpler answer at hand.
  13. actually thoughtful at 08:36 AM on 5 December 2010
    The human fingerprint in the seasons
    Sphaerica - we KNOW there is no notable solar input to the current warming - from direct measurements of insolation, not from the seasonal patterns this post discusses (although the data here re-confirms the fact of no solar fingerprint). It seems my analogy stands.
  14. 2009-2010 winter saw record cold spells
    11 & 12 - Sure it's not winter 2009-2010, but given the change in Arctic weather patterns, it may become an annual skeptic talking point.
  15. Renewable Baseload Energy
    Camburn @ 350... Can you really not see that you are doing exactly what you are claiming renewables proponents are doing? You are presenting nuclear as a "proven technology" that we should be "crowing from the rooftops" about. That says to me that you are completely ignoring the inherent negative aspects of nuclear. And again, you are also ignoring that nuclear can't switched off when people go to bed at night. That means you run spin reserve. So, ultimately nuclear is not very flexible. The larger a percentage of output that is dedicated to nuclear the less efficient it is. Renewables are exactly the opposite. Everyone here is saying both are needed to address the issue of AGW. Neither is a panacea. Both have strengths and weaknesses. But we need to do everything we can to limit our use of fossil fuels. The only thing I'm going to crow from the rooftop about is our political leaders accepting publicly that we need to address this important issue so that we can begin to get serious about it.
  16. Stratospheric Cooling and Tropospheric Warming
    Guys, I guess I'm thinking of one thing after another. The troposphere. More CO2 so more absorption of IR. This causes the vibrational energy of CO2 molecules to increase. Somehow this vibrationalal energy gets converted to K.E. to increase the temperature. In this case, a collision results in more k.e. of the particles. Right? My intuition here is not as solid even though this is probably what is happening. Bob
  17. The human fingerprint in the seasons
    The prescription medicine would still be detectable through multiple methods. Historical solar irradiance changes are also detectable.
  18. Stratospheric Cooling and Tropospheric Warming
    Sphaerica and everybody else who helped me. I'm sure that temperature differentials play a role in all of this but getting into that would just add complexity to a nice and simple model and make the essence of all of this more difficult to understand. Do you agree? Bob
  19. The human fingerprint in the seasons
    actually thoughtful, I think you missed HR's point. The fact is that either a solar or CO2 initial forcing will be accompanied by a strong H2O GHG positive feedback. That strong positive feedback will have the same GHG signature, and that will obscure the fact that in the case of solar forcing the initial forcing does not have such a signature. In your analogy, a better example would be for two different drivers, one who drank a lot of alcohol, and another who drank a little bit of alcohol, but combined it with prescription medicine. Both test positive for a blood alcohol content over the limit, and both caused horrific car crashes, and in that way the two are difficult to distinguish, but the prescription medicine distinction is lost without further evidence to support it.
  20. Stratospheric Cooling and Tropospheric Warming
    Sphaerica, You said: As a result, the CO2 in the troposphere is more likely to absorb IR in that narrow CO2 band, but then passes it on through collisions to the abundant, non-emitting O2/N2, raising temperatures and somewhat "blocking" that band of radiation. Alternately, the CO2 in the more rarefied stratosphere is more often excited by collisions with the more abundant O2/N2, and emits the gained energy through radiation before it can pass it on through another collision. Me: I can't believe this but I understand this perfectly. I've had one of those Eureka moments. I'll add one fine point for total clarity or maybe I'm simply rephrasing what you guys have said. And I'm keeping with my very simple model of an atmosphere of two layers, the troposphere and stratosphere and composed only of nitrogen and carbon dioxide. Temperature depends only upon the kinetic energy of the molecules. Thus, after a collision, a molecule with no vibrational energy may now have vibrational energy and that molecule has less kinetic energy. So this diminution of kinetic energy from multiple molecules lowers the temperature. That molecule that has more vibrational energy deexcites and emits IR that may be absorbed by another deexcited molecule or it may simply fly off into space. This IR flying off into space is kinetic energy that is now lost forever from the stratosphere. I also now believe that, as Tom has stated, it doesn't matter whether we are talking about the steady state or the transient state with these states being as I have defined them. So I can now make my model simpler yet. I won't talk about whether or not we are at equilibrium! It's amazing how much you can do in Physics without the heavy mathematics. Just say "you've got it!" and I'll run with it. I also would like all you guys that helped me to send me email so that I can acknowledge you with your real names and, something tells me, titles. robertguercio@optonline.net Thank you, Bob
  21. Stratospheric Cooling and Tropospheric Warming
    Bob,
    Are you guys interpreting these two very important emails the same way that I am?
    Yes, I think that's exactly it, it all seems to add up to the fact that the primary mechanism by far is IR emission by CO2 in the stratosphere, as professor Robock explicitly says and Gavin implies when he says "First, all GHGs emit as well as absorb, and whether you will get warming or cooling in a region depends on the ratio of the change in absorption and the change in emittence." I think Gavin's spot-on comment probably meant that what you told him was correctly stated, but he didn't emphasize how much importance lay in the pieces missed.
  22. 2nd law of thermodynamics contradicts greenhouse theory
    Re #294 Tom Dayton you wrote:- " I can't get past even your second paragraph, which seems to be gibberish." My 2nd para. goes like this:- 'Sun/Earth system is in considerable disequilibrium.' You may not be familiar with the thermodynamic meaning of the term 'equilibrium'; a thermal system is out of equilibrium when there is a temperature difference inside the system. This means that the entropy is below the maximum and there will be energy transport within the system according to the 2nd law of thermodynamics. The reason why the wavelength of incoming radiation is of no great importance is fairly simple; incoming radiation is either scattered (the albedo or reflected, if you like) or absorbed; the third possibility, transmitted, is not generally considered in planetary physics for reasons that should be self-evident. By definition the absorption does not affect the scattering, it is the scattering that affects the absorption. However it remains true that the scattering that gives the albedo its characteristic wavelength function i.e. its spectral characteristic. From this you will realise that the total scattering depends only on the amount of scatteing material present and the magnitude of the scattering is independent of the direction of arrival of the scattered wave; meaning the material that causes the albedo (scattered solar radiation) will have the same total effect on the emitted radiation, even though the response is in a different part of the spectrum. It is this that makes the emissivity and absoptivity the same in terms of power, even if not at the same frequency.
  23. A basic overview of Antarctic ice
    Albatross at 05:19 AM on 5 December, 2010 "PS: I have not "cherry-picked" data, nor is applying an OLS model and stating the statistical significance of the model fit "arm waving"." I didn't mean to imply you were arm waving. My reply was to Phillipe. I think our conversation was being productive until Phillipe stepped in and flat made a claim that global ice loss was statistically significant because on a graph it appeared to be. There was nothing unique about such an observation because we know ice melts and we can see it. My similar statement was not based on the visual graph but was a rough rule of thumb mathematical estimate of the effect of reducing the ice loss percentage by 30 to 40% from subtracting the antarctic ice gain from the arctic ice loss and by increasing the extent by 50% by adding the Antarctic maximum extent to the Arctic maximum extent. Should come out to be roughly the same significance as the Antarctic ice gain though it may fall on either side of the arbitrary significance line. Perhaps Phillipe misinterpreted what I was estimating. Consistently pursuing these arguments will remove any arm waving whether intended or not. Then of course to move the conservation forward in the spirit of consistency, it is always important to include all the elements of a theory in your theory. If the theory is feedback from loss of polar albedo (polar amplification) then the antarctic land mass should also be included in the calculations to estimate the significance of polar albedo loss (and polar amplification) to determine if the loss of albedo is in fact currently statistically significant. I think this is entirely consistent with the mathematical approach you offered in post #74 and allows each argument to be fully weighed in and avoid inconsistencies. My comment on "other months" was simply a layman's observation that the arctic ice extent differences seem relatively compressed during the equinoxes as opposed to the solstices. Since albedo is an ongoing year round phenomena I simply thought they should also be included though I realize that significantly ups the workload. I think it is important to get to solid answers as populations and the use of plant resources continue to accelerate. And the only way to get to solid answers is through a combination of critical, complete, accurate, and consistent collection and evaluation of data. Where we can go astray as a specie is through improper weighting of risks. The weighting of risks is inherently (philosophically and functionally) democratic in nature as none of us possess crystal balls and crystal balls is all we have until we get solid answers. Because of that fact, the only thing to be achieved by inconsistency is the exact opposite of that which we wish to achieve. That issue has already been well explored in philosophical and psychological literature and represents an ongoing concern supporting the viewpoint of Judith Curry.
  24. We're heading into an ice age
    #150: "poor ability to predict the glacial cycle using models" You are aware that the Oerlemans paper you refer to bases its explanation on a model study? Experiments with a Northern Hemisphere ice-sheet model show that the 100,000-yr cycle and its sawtooth shape may be explained by ice sheet/bedrock dynamics alone. This cycle seems to be an internally generated feature and is not forced by variations in the eccentricity of the Earth's orbit. Too bad just about everybody else goes with the orbital variations.
  25. Positive feedback means runaway warming
    It probably goes without saying, so I didn't bother saying this in my comment above. But obviously the consequences of a Venusian style runaway warming are so completely unacceptable, that even a very small probability of that outcome needs to be taken seriously. So I guess I'd characterize my position as "this is very unlikely to happen, but we should be investing a lot more in understanding the relevant processes (clathrates, etc.) just in case".
  26. actually thoughtful at 06:32 AM on 5 December 2010
    The human fingerprint in the seasons
    Humanity Rules introduces a new, high bar for a fingerprint. Let's apply it to a different milieu and see what happens. I go out and get drunk. I drive home, hit another car with a woman and 2 kids. They all die. One would expect that I would be charged and convicted with vehicular manslaughter, DUI and a few other crimes. Enter HRlogic! As I myself did not hit the other vehicle (it was rather my vehicle that hit their vehicle; indeed those poor unfortunates did not die from *my* car - it was instead various objects within their own vehicle that led to their untimely death. No fingerprint here). But it gets worse! My actual fingerprints are on the glass that contained the alcohol - 1) I didn't touch the alcohol 2)Even if you ignore the HRlogic in (1) - yes, I drank the alcohol - the fact that this alcohol interacted in predictable, knowable ways with my own biochemistry is not my fault - my only fingerprints are on the glass! The jury, following HRlogic, finds me innocent! I am back in the bars now. HR - care to drive in my town around 2am (when said bars close and me and my HRlogic fingers are driving home again)?
  27. The human fingerprint in the seasons
    #52: Chris G, nice approach! Hope you don't mind, I tweaked it a bit and came up with a similar plot. I started in 1900.05 (January 15) and used a 3 sample average (hoping this would give a seasonal winter, ie DJF average). Then picked every 12 (should now be each winter) and then applied a smaller mean (since the dataset should now be sampled in years). Similarly for summers (JJA) beginnning in 1900.6. I hope I'm not reading too much into WFT's ability to resample monthly data into annual. Indeed winter rises faster than summer, although not by as much as NH rises faster than SH.
  28. Renewable Baseload Energy
    Rob@348: No one thinks nuclear is the only solution. People who believe in AGW should be shouting from the rooftops for nuclear. It is proven tech. They aren't. It shows the falasy of their arguement. Baseload is extremely important to people. Cost is extremely important to people. I don't believe in the magnitude of GAWG that some do. The error bars, the missing links in the hypothosis all point out that it is not as strong as some would have others believe. I am a conservative, and have not figured out, now that the opportunity has presented itself, why we are not building more nuclear baseload plants to take the place of coal/petroleum/gas power plants. We have a resource that is available for over 1,000 years. Rather than burn a short term finite resource, it makes much more sense to use a long term resource. The cost of implimenting a grid system to try and provide "baseload" ability of solar/wind is huge. We have infrastructure in place to utilize nuclear right now. Reliable, baseload power. The future is in elec vehicles for short spans of travel. Those vehicles will be recharged at night for the most part. Interuptions of available electricity will only slow the advancement of elec propulsion on a large scale. That is why in an earlier comment I stated that CPS makes sense in the southwest, but not really anywhere else. Nuclear can and should be filling that gap. It is a win win for everyone.
  29. We're heading into an ice age
    This article is quite interesting as well. It explains ice sheet/bedrock dynamics, and explains the rapid deglaciation. He also contends that ice sheet/earth crust dynamics are enough to explain the 100,000 year cycle. He contends that raised bedrock and low summer insolation are enough to start the next glaciation cycle. http://igitur-archive.library.uu.nl/phys/2007-0730-200322/oerlemans_80_modelexperiments100000yr.pdf Chris Shaker
  30. We're heading into an ice age
    Daniel Bailey asks And your source for that claim would be...? Re: cjshaker >"I think the bottom line is that climate modelers don't really understand the glacial >cycle, nor how it really works." I make that claim because of articles like this one, which appear to show poor ability to predict the glacial cycle using models http://www.igsoc.org/annals/5/igs_annals_vol05_year1984_pg213-214.pdf And this one, which attempts to use spectral analysis to predict future behavior of the glacial cycle http://www.nosams.whoi.edu/PDFs/papers/surveysingeo_time_series.pdf Chris Shaker
  31. A basic overview of Antarctic ice
    Bill, "Since it appears to be statistically insignificant it probably either is or very close to it." Now the goal posts shift, again. OK, I'll look into that for you. But I have a bunch of things to take care of this weekend...so please be patient. Actually, I do not have the global data for sea ice. Those data I showed earlier were area from NSIDC while the graph I posted was extent data from "Cryosphere today". PS: I have not "cherry-picked" data, nor is applying an OLS model and stating the statistical significance of the model fit "arm waving". The reason for me selecting the months I did is because (if you have read the original post) we have been discussing the impact of changes in albedo around the time of the solstices.
  32. actually thoughtful at 05:01 AM on 5 December 2010
    Renewable Baseload Energy
    Based on this thread, I have come to some conclusions for energy goals in the United States. Currently electricity comes from the following sources: 2005 energy production Source: http://montaraventures.com/blog/2006/10/09/how-does-the-us-produce-electricity/ So, we need a future that is different. Based on the statement that 60% of energy consumption is baseload, we should aim for for a fossil free future that looks something like this: coal 0% nuclear 30% petroleum 0% hydro 5% renewable 65% gas backup (normally not used, but available): 20% This will require an intermediate stage where gas takes on a larger role as we get off of coal and ramp up renewables and supporting technologies.
    Moderator Response: Fixed image tag.
  33. Stratospheric Cooling and Tropospheric Warming
    Folks, I corresponded via email with a distinguished professor at Rutgers and this is that correspondence. Dear Bob, You correctly wrote up what Gavin told you, but he is wrong. The stratosphere cools because its emissivity goes up with more CO2, and it still absorbs the same amount of energy being emitted from below. It is a balance of energy. You cannot just look at one term. Designing a graph with not enough room to do it correctly is not a good reason in my opinion to do it wrong. Alan Alan Robock, Professor II (Distinguished Professor) Editor, Reviews of Geophysics Director, Meteorology Undergraduate Program Department of Environmental Sciences Phone: +1-732-932-9800 x6222 Rutgers University Fax: +1-732-932-8644 14 College Farm Road E-mail: robock@envsci.rutgers.edu New Brunswick, NJ 08901-8551 USA http://envsci.rutgers.edu/~robock On 12/2/2010 10:22 AM, Robert Guercio wrote: > Dear Alan, > > I'm sure you're correct; however, here is the email correspondence > that I had with Gavin. > > The ordinate should be (watts/meter square wavenumber) and I had > trouble making it all fit. I was actually working pixel by pixel and > I guess I was a bit lazy but that is easily corrected. > > The solar insolation that I used was very fictitious as everything > about my model is. I just kept on playing with different numbers > until the fictional atmosphere that I came up with made for "good" > graphs. > > Bob > > > > ----- Original Message ----- From: "RealClimate" > > To: "Robert Guercio" > Sent: Friday, November 19, 2010 8:03 PM > Subject: Re: Stratospheric Cooling > > >> mostly right. You miss two key facts. First, all GHGs emit as well as >> absorb, and whether you will get warming or cooling in a region >> depends on >> the ratio of the change in absorption and the change in emittence. >> >> Second, the troposphere has many IR absorbers, the stratosphere only two >> (CO2 and O3 - everything else is minor). So the impact of CO2 above the >> tropopause is amplified. >> >> Otherwise you are spot on! >> >> Gavin >> >>> Hi, >>> >>> I've searched for an explanation of the reason that the Stratosphere >>> cools >>> due to Global Warming and have not found a satisfactory answer. There >>> does seem to be quite a bit of hand waving though. >>> >>> I think that I now understand it but would like the confirmation of a >>> professional. If my understanding is correct, I would like to write a >>> blog on this most misunderstood subject. >>> >>> Please confirm if this is correct. >>> >>> Thank you, >>> >>> Robert Guercio >>> >>> The earth radiates Infrared Radiation in accordance with Black Body >>> theory. Most of the IR energy absorbed by CO2 has wave numbers of >>> approximately 650 and 1050. There is CO2 in both the troposphere and >>> the >>> stratosphere so frequencies associated with these wave numbers >>> emanating >>> from the heated earth heat up both the troposphere and the >>> stratosphere. >>> Frequencies of all other wave numbers simply sail on through without >>> effecting either layer. >>> >>> If there is more CO2 in the troposphere, more of a chunk of the >>> spectrum >>> is going to be taken out around these two wave numbers in heating up >>> the >>> troposphere. Therefore, there is less energy in these two IR bands >>> to heat >>> up the CO2 in the stratosphere and thus the stratosphere cools. >>> >> I don't think Gavin was wrong. I'm interpreting this email to mean that the mechanism of my blog is not significant in comparison to the second method that I am now learning. I think Gavin's email to me was, to use his words, "Spot On". Here it is again posted: mostly right. You miss two key facts. First, all GHGs emit as well as absorb, and whether you will get warming or cooling in a region depends on the ratio of the change in absorption and the change in emittence. Second, the troposphere has many IR absorbers, the stratosphere only two (CO2 and O3 - everything else is minor). So the impact of CO2 above the tropopause is amplified. Otherwise you are spot on! Gavin > Hi, > > I've searched for an explanation of the reason that the Stratosphere cools > due to Global Warming and have not found a satisfactory answer. There > does seem to be quite a bit of hand waving though. > > I think that I now understand it but would like the confirmation of a > professional. If my understanding is correct, I would like to write a > blog on this most misunderstood subject. > > Please confirm if this is correct. > > Thank you, > > Robert Guercio > > The earth radiates Infrared Radiation in accordance with Black Body > theory. Most of the IR energy absorbed by CO2 has wave numbers of > approximately 650 and 1050. There is CO2 in both the troposphere and the > stratosphere so frequencies associated with these wave numbers emanating > from the heated earth heat up both the troposphere and the stratosphere. > Frequencies of all other wave numbers simply sail on through without > effecting either layer. > > If there is more CO2 in the troposphere, more of a chunk of the spectrum > is going to be taken out around these two wave numbers in heating up the > troposphere. Therefore, there is less energy in these two IR bands to heat > up the CO2 in the stratosphere and thus the stratosphere cools. > His first comment, in my opinion, addresses what you guys are saying. His second comment addresses my blog. But he didn't say which one was more important. So I'm saying that Gavin addressed both methods and I picked up on only one. I'm interpreting my method as trivial because of Dr. Roboks comment that Gavin was wrong. Are you guys interpreting these two very important emails the same way that I am? Again thank much, Bob
  34. Ocean acidification isn't serious
    The bleaching of coral reefs seems to actually be caused by fungus, which is transported across oceans by dust in the wind as the climate naturally warms and dries. http://imars.usf.edu/~cmoses/PDF_Library/Shinn%20et%20al%202000.pdf It looks like fungi have been attacking coral reefs for a long time http://www.biolbull.org/cgi/reprint/198/2/254.pdf Chris Shaker
  35. Stratospheric Cooling and Tropospheric Warming
    Sphaerica So CO2 prevents energy from escaping from the troposphere into the stratosphere in the CO2-IR bandwidth, My blog does this. and CO2 actively cools the stratosphere by emitting energy in the CO2-IR bandwidth. Once I fully understand this, I'll incorporate it into my blog and maybe it will be complete. This sentence that you wrote would be part of my opening statement. And then my blog, as it is now, would address the first method and I'll then add the second method. This has been like wrestling an alligator. The problem is that, as far as professionals are concerned, all this is so trivial that they wouldn't waste their time on it. It's probably in some climate textbook or maybe not; maybe it's a problem at the end of some chapter on stratospheric chemistry or some such name! Thank you, Bob
  36. The human fingerprint in the seasons
    HR @55, "So fingerprint = correlation? Is that all? Wow." Umm, not quite. Read some more of Santer's seminal works. Earlier you said "The problem I have is that those two options aren't the only possibilities." Referring to options other than solar and volcanic forcing. But then @ 55 you misrepresent the findings form a study to try and support the “it’s the sun” argument. Also, I asked you to present a model here which does not include solar or volcanoes and that explains the nature of the observed long-term warming trend.
  37. A basic overview of Antarctic ice
    Philippe Chantreau at 03:04 AM on 5 December, 2010 "I don't know how one can look at the data and come to that conclusion. Whatever analysis this assertion is based on is in error. The decline of global sea ice is statistically significant." The claim was made based upon a monthly analysis that ice gain in the Antarctic which also is visibly easy to see on a graph was NOT statistically significant. Thus the appropriate response would be that since there is a positive trend provided by the southern ice that reduces the loss of Arctic ice by nearly half on a month by month basis that the trend globally may also not be statistically significant. When one decreases the percentage of ice loss by both increasing the denominator and decreasing the numerator a mathematical answer is called for. Saying it is easily visible is not an appropriate response when somebody had already responded that something that is easily visible mathematically is not significant. (i.e. antarctic ice gain). The correct response is a third category, which Albatross can easily do as he obviously already has all the data and we can get away from the highly unscientific approach of arguing via cherry picking mathematical tests vs visual tests. All that is required to test this hypothesis is to add the two categories together in post #74 and do the math. An interesting variation if our objective is to test the statistic significance of the "pole" albedo issue would be to add in the land mass of antarctic as virtual sea ice serving the same purpose the core area of the Arctic serves. In that way we could test the statistical significance of "pole" ice. Then we can really begin to treat these issues consistently and better weigh the significance of each argument in a consistent manner without a lot of arm waving.
  38. Stratospheric Cooling and Tropospheric Warming
    Dan, Success! Thank you, Bob
  39. 2nd law of thermodynamics contradicts greenhouse theory
    damorbel #277: "How so? A has only 10% absorption capacity, B has 75%. Now the absorption capacity is always equal to the emission capacity, after all the reflection part cannot emit as well as reflect, can it? So both objects have the same temperature, any difference would clearly break the 2nd Law of thermodynamics." I'm sorry, but what part of 75 units of energy is greater than 10 units of energy don't you understand? Yes, an object cannot emit more energy than it absorbs. Ergo, if the more reflective object is only absorbing 10 units of energy it can only emit 10 units of energy. Those 10 plus the 90 reflected equal the 100 total incoming and thus incoming and outgoing energy are in balance. Ditto the less reflective object except that it is absorbing and emitting 75 units of energy. 75 > 10. It has absorbed and is emitting more energy. Higher energy absorption and emissions equals higher temperature. For the 90% reflective object to be the same temperature it would have to be emitting the same 75 units of energy... which added to the 90 units reflected would be 165 units total... which runs afoul of the law of conservation of energy... an extra 65 units of energy can't just spontaneously appear from nothing. You seem to be arguing that absorption and emission are the same for all objects... rather than that they are the same for each object. That clearly isn't the case because an object can't absorb energy it has reflected away. Taking Tom's example of a theoretically 100% reflective object it is clear that it would absorb no energy... and thus would be at absolute zero. The more energy an object reflects the less it absorbs and the colder it is.
  40. Stratospheric Cooling and Tropospheric Warming
    Re: Bob Guercio (137) 1. First type this symbol: < 2. Next, type: img width="500" src="http://image_url/" 3. Replace the URL in Double Quotes "" with the actual URL intended 4. A common error is to have an extra / at the end of the URL; this can be avoided by using the preview function Hope this helps! The Yooper
  41. 2009-2010 winter saw record cold spells
    Re: Rob Painting (10) Here's one from January 7th, 2010
  42. Stratospheric Cooling and Tropospheric Warming
    Bob Moderator Response: Fixed. See the help on posting images; you need an html tag: img src= "url" width=no more than 500 inside the usual lt and gt brackets. I don't get it. Could you please put exactly what you typed inside quotes or brackets. Thank you, Bob
  43. Renewable Baseload Energy
    Camburn @ 344... "What this thread shows is the reluctance of people to address co2 emmissions with the tech that is available and proven." This is patently, and utterly false. Virtually everyone here who has posted has stated they believe that nuclear belongs as a solution to CO2. What people here are NOT willing to say is that it is the ONLY solution. Conversely, the the nuclear proponents have been completely unwilling to accept any of the positive aspects of renewables. As I stated previously nuclear does somethings very very well. Stable, level output. If we needed exactly that then nuclear would be the perfect solution. That is NOT what is required. That does not perfectly address electrical demand. I'm sorry if you can't see it but nuclear also has negatives that nuclear proponents like Peter Lang are unwilling or incapable of seeing. And, once again, the grid level storage solutions presented in Dana's original article apply equally well to mitigating the losses of nuclear spin reserve off-peak as it does to the intermittency of renewables.
  44. Stratospheric Cooling and Tropospheric Warming
    134.Sphaerica at 03:12 AM on 5 December, 2010 Bob, I actually think that once you sort it out, you can come up with a simple explanation. . Figuring what to leave out is the key to any simple model created for explanatory purposes, as you well know (and despite what the "it's not realistic" crowd moronically screams). I think that I understand what you are saying. Regarding your comment about realism, I doubt if these people have ever had even a basic Physics or Chemistry course. Bob
  45. Renewable Baseload Energy
    Another irony about people who push nuclear as The Solution is that many of them also argue that there is no problem; references to CAGW are a plain indicator. Lang has provided a good service here though. His posts have been a case study in how not to discuss a contentious topic. This was a thread about renewable baseload & how it could be achieved. Exhortations that such a feat is impossible belong aside those that heavier than air flight is impossible.
  46. The human fingerprint in the seasons
    55 (Humanity Rules), I don't see what you see. I went through the review, and while there are frequent references to the terms "winter", "summer" and "season", they almost all have to do with data studied being limited to a particular season (e.g. MWP winters), not comparisons between the two. The only reference to a specific difference in the seasons has to do with stratospheric wind patterns, and even these were inferred from model runs, not observations. I find nothing at all in the review to support your claim. Alternately, the review also says this:
    ...many of these solar-climate associations also seemed highly improbable simply on the basis of quantitative energetic considerations.
    and
    Recent estimates suggest a radiative forcing drift associated with solar irradiance changes of 0.017 Wm-2 per decade (see section 2). In comparison, the current rate of increase in trace greenhouse gas radiative forcing is about 0.30 Wm-2 per decade (Hofmann et al., 2008).
    So I'm not sure how anyone could make any observations on seasonal impacts of solar variations when there haven't been any.
  47. Stratospheric Cooling and Tropospheric Warming
    Hi All, I've tried to post an image but again I am not successful. Could someone take care of this for me and then show me the exact code used for this image. I was going to ask the question "The ozone layer is not at the top of the stratosphere so how does heating of the ozone layer cause the temperature to be the highest at the top?" But then I saw this image which shows the temperature increasing and then decreasing as you go up through the statosphere. This is what I would expect. That said, how is the stratosphere defined. Apparently it is not simply simply defined by a negative lapse rate! Bob
    Moderator Response: Fixed. See the help on posting images; you need an html tag: img src= "url" width=no more than 500 inside the usual lt and gt brackets.
  48. Stratospheric Cooling and Tropospheric Warming
    Bob, I actually think that once you sort it out, you can come up with a simple explanation. A lot of the complications can still be removed. The difficulty with anything like this lies primarily in removing relatively inconsequential complications. The reader probably does not need to know that the stratosphere is heated through UV and ozone creation, or what "optical thickness" means (that is a very confusing, obscure term that is meaningful to people that are familiar with it, but requires a paragraph just to explain, and so distracts and confuses the reader). Terms like "adiabatic lapse rate" and the 15 micron issue are similarly confusing details which do not really add anything to the heart of the explanation. A lot of things can be left out. Figuring what to leave out is the key to any simple model created for explanatory purposes, as you well know (and despite what the "it's not realistic" crowd moronically screams). The only factor that you really need to incorporate with what you have already written, IMO, is that energy is transferred at the molecular level via collision or emission/absorption, and in varying proportions depending on the density of the atmosphere. The main point is simply that energy can be absorbed one way but then surrendered in another, so that at equilibrium the total-radiation-in need not equal total-radiation-out in a particular band. As a result, the CO2 in the troposphere is more likely to absorb IR in that narrow CO2 band, but then passes it on through collisions to the abundant, non-emitting O2/N2, raising temperatures and somewhat "blocking" that band of radiation. Alternately, the CO2 in the more rarefied stratosphere is more often excited by collisions with the more abundant O2/N2, and emits the gained energy through radiation before it can pass it on through another collision. So CO2 prevents energy from escaping from the troposphere into the stratosphere in the CO2-IR bandwidth, and CO2 actively cools the stratosphere by emitting energy in the CO2-IR bandwidth. The only question left to clarify is relative amounts of these mechanisms (i.e. how much does stratospheric emission contribute to cooling, versus tropospheric "blocking"). I suspect that the latter is minor, at least as far as its influence on stratospheric temperatures (but I don't know).
  49. Renewable Baseload Energy
    Here are some more interesting links of actual projects/studies/companies in the field how to make renewable more reliable. - The first IEEE smart grid symposium - German company "energymeteo" - Australian company CSIRO - virtual power plant - RWE & Siemens effort: review article on VPP - VPP, microgrids, energy hubs: overview (semester thesis by R. Bühler from ETH Zürich, CH) To me it looks like the concept behind distributed energy production and virtual combination to be able to work on centralized offering for customers is gaining more and more attention and is leaving the concept/theory phase, entering in the demonstration/piloting phase around the globe.
  50. The human fingerprint in the seasons
    Alexandre to quote from the review linked by HumanityRules:
    There have been suggestions that 20th century global and hemispheric mean surface temperature variations are correlated to longer-term solar variations. Advanced statistical detection and attribution methodologies confirm that solar forcing contributed to the increase in global temperatures in the early part of the century but for the latter part of the 20th century they consistently find that using realistic variations, solar forcing played only a minor role in global warming, in agreement with the practically constant mean solar forcing since 1980.
    The passing of time doesn't apper to help the "it's the sun" supporters.

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