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Comments 102201 to 102250:

  1. Ocean acidification isn't serious
    Most references I see on coral bleaching list increased temperature as the main stress likely to cause it. Reading the wiki on Coral bleaching seems to offer a contradiction http://en.wikipedia.org/wiki/Coral_bleaching It says, "Bleaching occurs when the conditions necessary to sustain the coral's zooxanthellae cannot be maintained.[4] Any environmental trigger that affects the coral's ability to supply the zooxanthellae with nutrients for photosynthesis (carbon dioxide, ammonium) will lead to the zooxanthellae's expulsion.". That seems to say that CO2 is required for photosynthesis. Yet, they also state, "Coral bleaching is a vivid sign of corals responding to stress, which can be induced by any of: increased (most commonly), or reduced water temperatures[5][6] increased solar irradiance (photosynthetically active radiation and ultraviolet band light)[7] changes in water chemistry (in particular acidification)[8][9] starvation caused by a decline in zooplankton[10] increased sedimentation (due to silt runoff) pathogen infections changes in salinity wind[6] low tide air exposure[6] cyanide fishing" How much stock am I supposed to put in the 'acidification' mention when CO2 appears to be essential for coral photosynthesis? Chris Shaker
  2. Ocean acidification isn't serious
    Rob: I searched for, found, and read that paper after watching an educational TV program that covered the fungus, possibly a Nova? Chris Shaker
  3. Ocean acidification isn't serious
    Chris , I find it insightful to actually read the studies linked to. The authors are proposing a hypothesis (back in 2000). They claim that two bleaching events in the Caribbean (1983/1987) coincide with increases in dust transport into the region. They lay the foundations for their hypothesis, that's the extent of it. In those two years (1983/1987) anomalously warm waters occurred too. Furthermore 1988 was a year of Caribbean coral bleaching and according the graph in Shinn 2000, this was a year of very low dust import into the region. In the meantime, coral reefs the world over have begun to bleach, as sea surface temperatures rise (see links at @ 19 for instance). I would certainly be interested to see how the authors of that study explain that away on African dust. I don't doubt that the transport of dust into the caribbean region has an influence of the marine life, however the evidence for warming waters as the cause of coral bleaching has strengthened to such a level that scientists are now able to accurately forecast bleaching events: Coral bleaching forecast - Coral Bleaching Likely in Caribbean This Year - Sept 22 2010 And reality: Caribbean Coral Die-Off Could Be Worst Ever - 14 Oct 2010 And yes, coral diseases are a major problem, often after bleaching events have occurred.
  4. Renewable Baseload Energy
    Peter Lang - you were promoting nuclear on economics ground alone. I looked to see what expected nuclear pricing would be. Extremely confusing. I found this reference World nuclear which at least made sense with number that I know well. I gather you think the newer technologies like IFR and LFTR would be cheaper still?
  5. A Cloudy Outlook for Low Climate Sensitivity
    Thanks all. David, I suspect the logic goes that in the short-term, cloud feedbacks will prevent dangerously rapid warming, and in the long-term we'll eventually move away from our reliance on fossil fuels. After all, they're limited resources anyway (particularly oil). I suspect the (wishful) thinking is that we'll run out of oil before climate change becomes too dangerous. And of course there's always the 'warmer is better' mentality - I'm not sure if the Lindzens and Spencers subscribe to that, but many skeptics do.
  6. A Cloudy Outlook for Low Climate Sensitivity
    David, as I understand it, people in denial (of any sort) grasp for anything that will allow them to keep their illusion that "everything's going to be all right". To maintain the fiction is all that matters, even if it means saying the sky is green and the sun rises in the west...
  7. A Cloudy Outlook for Low Climate Sensitivity
    What I have never understood about the Lindzen-Spencer position is what do they see happening in the longer term? The clouds don't stop the CO2 build up, so even if they were right, the rise and rise in greenhouse gas concentrations would overwhelm the cloud effect. Or do they imagine cloud cover getting thicker and thicker for the rest of the century keeping pace with rising CO2? And what would be the effect of that on agriculture and the environment? The only relevant negative feedback would be one that began removing CO2 faster than we could pump it into the atmosphere, and there is, sadly, nothing that can do that. And yet people keep quoting Spencer as if this clouds are some kind of serendipitous mechanism that will providentially save us all, no need to worry, keep burning fossil fuel as fast as you like. Or am I missing something in the logic of all this?
  8. The human fingerprint in the seasons
    Muon, Yes, my graph is essentially a running mean with a 66-year window. (I think this is less than clear on the graph because the curve is justified on the left edge of the aggregation window rather than centered.) The data are noisy and if you can't explain the noise, the best thing to do is average it out. I like to use multiples of 11 because I surmise that the solar cycle will have some effect, and it is about 11 years long on average, and using a window over one complete wave, or multiples of the wave, is the best way to smooth out the noise induced by that wave. As a matter of preference, when I am making a picture depicting the larger effects, I like to average, or otherwise smooth out, the smaller ones. Tom, I read your posts and I hunted up some other material, and I agree it is true that the stratosphere will be cooler than it was even after a new equilibrium is reached largely because of the blockage from below and increased radiative energy loss from above, but I don't believe it is the only game in town. I do have some quibbles: I don't think it is very accurate to categorize the whole troposphere as optically thick. The mean altitude of emission is 5-6km, and that is about half the average altitude of the tropopause. So, the troposphere is getting optically thin at some point below the stratosphere. Optically, I don't think there is a clear cut-off between thick and thin; so, this is somewhat a matter of how they are defined. In a state of equilibrium, a body emits the same amount of energy as it receives. If slightly more insulation is added to the body, then the emission will be less than it was until a new, higher equilibrium temperature is reached. You can't raise the energy level within a body while keeping the inflow the same unless you reduce the outflow. In the case of the earth, the reduction of outflow would be observed as stratospheric cooling. The pattern of a warmer surface and a cooler stratosphere this effect causes would be be hard to distinguish between H2O and CO2. I think you are taking the blanket analogy a bit too literally. If it makes you like it any better, you can say that it is a body in space (like the earth is a body in space) that is tightly covered in a thin insulating layer that does not appreciably change its surface area. I mean, if you define the surface area by using the optical TOA, what is the difference in surface area between an earth with 287 ppm CO2 and one with 385 ppm CO2, and what is this difference in comparison to the total surface area? Without doing the math, I can ballpark it as pretty dang negligible. So, it doesn't make a great deal of sense to introduce the idea that adding more insulation to the body appreciably changes the surface area from which it emits. Convection doesn't transfer energy in space. A cold-blooded animal is a poorer analogy than some generic body of matter receiving energy because said animals in time achieve the same temperature as their surroundings. In contrast, of course, the earth is continually receiving energy from the sun and stays considerably warmer than the surrounding space, if you could say that space has a temperature. Blankets also limit radiative energy loss.
  9. Philippe Chantreau at 17:57 PM on 5 December 2010
    A basic overview of Antarctic ice
    Bill, you make it easy to misinterpret. What exactly are you trying to say, in a few words? This: "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." What is the point of such manipulations? The only way to assess the significance of global sea ice loss is to examine real global sea ice data. Do it daily, monthly, whatever but I doubt that building fictitious quantities by adding numbers at various times of the year can show much about reality. "Since albedo is an ongoing year round phenomena." In the same sentence, you mention Arctic sea ice, so I assume that the albedo statement pertains to Arctic sea ice. Are you serious? I have very little time to devote to climate blogging these days. From a cursory read of your posts above, it does not appear that your assertion that the global sea ice decline is not statistically significant was supported by a real data analysis. Was it the case or not? What I read from you does not appear any better, a priori, than eyeballing a graph. I contend that data analysis from either NSIDC or CT will show that the decline in global sea ice is statistically significant. I have not the leisure of going at length about it. Tamino looked at the numbers again not long ago: "For the Southern Hemisphere, summer minimum has increased at about 9,000 km^2/yr while the winter maximum has increased at about 14,000 km^2/yr. For the Northern Hemisphere, on the other hand, the decrease in winter maximum has been about 42,000 km^2/yr and the decrease in summer minimum has proceeded at about 81,000 km^2/yr." The differences between these rates leaves little doubt IMO but feel free to attempt proving otherwise.
  10. Renewable Baseload Energy
    The one great advantage of renewables from my perspective is that they circumvent one of the major unknowns of the next century or so. Just how much hotter and drier it will get, and how long will they stay that way, before things improve. Renewables need no cooling water for operation. If France and the USA have already had to take plants offline when rivers ran hot or low, we really don't want to put too many of our eggs in a basket that needs reliable flows of cooling water. And I'd be very reluctant to put a coal or nuclear plant that has to operate 80 years from now at the shoreline to use seawater.
  11. A Cloudy Outlook for Low Climate Sensitivity
    Well done Dana. Of course it's not good news, but it at least gives some support for the "instinct" that low cloud sensitivity was more wishful thinking than anything else. On the bright side, someone else just possibly might do further quality work in this area with a better outlook. (If only.)
  12. Renewable Baseload Energy
    351 Rob Honeycutt
    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.
    Your assertion that nuclear power plants do not and cannot load follow is prevalent myth that is not true. French NPPs do adjust output according to load. I understand that German NPPs can also, but there is probably no grid requirement to do so. Areva states that the EPR can adjust output from 60% to 100% of nameplate capacity at the rate of 5% of nominal capacity per minute at constant temperature. (as per Areva website). Nuclear can handle base and a large portion of intermediate load economically. Exactly at what point it may be uneconomic would be grid specific and could only be determined by detailed modeling. I must confess to be utterly bamboozled by this argument that renewables are less "wasteful" - without even defining what wasteful means. One of the characteristics of grand plans for renewables is the requirement to overbuild capacity precisely because of the intermittent and unreliable nature of the generators. I would be very cautious of claims that demand can be time shifted by smart grids and clever gadgets until we see in practice the magnitude of any such change. I'm not prepared to bet the future of the climate on this stuff.
  13. It's albedo
    And, back to the previous question: "Has it been proven that the equilibrium temperature of a body in a constant EM radiation field can be altered by altering it's reflectivity [...] Is it not necessary to demonstrate that in order to prove that albedo or aerosol-based reflectance can influence the global mean temperature?" There are actually quite a few different ways you can see this operating in the real world. If you live in a place where it snows in the winter, you might notice dirty snow melting faster than clean snow -- because its lower albedo causes it to absorb more sunlight and warm up faster. The same principle is what makes ice ages cold ... as the large continental ice sheets expand, they reflect more sunlight back to space, which makes the local climate cooler, which helps the ice expand further. (When they begin melting, at the end of each glacial episode, the same process happens in reverse -- the loss of ice makes the landscape absorb more sunlight, making it warmer, which melts the ice further....)
  14. It's albedo
    Rovinpiper (bagpipes?), try playing with this calculator.
  15. It's albedo
    Hi, Rovinpiper. Good questions you're asking. Kirchoff's Law refers to absorptance and emissivity at the same wavelength -- i.e., an object's emissivity at a given wavelength will equal its absorptance at the same wavelength. In the case of a planet (e.g., earth), almost all the radiation it receives from the sun is at short wavelengths (UV, visible, and near-infrared). In contrast, all the radiation it emits is at long wavelengths (> 3 micrometers). So, a change in the earth's albedo can increase or decrease the amount of energy that is absorbed, without necessarily increasing or decreasing the amount of energy that is emitted. When this happens, the planet then warms or cools until the outgoing radiation is once again in balance with the incoming radiation. Hopefully that's clear. It's around midnight here and I'm not really a night person, so my explanations may not be all that coherent......
  16. It's albedo
    Hi Tom, Thanks for replying to my question. Do you have a solid source for a proof of that? I just read about Kirchoff's Law and it seems to say that if the Earth becomes more reflective it becomes less emissive by an equal amount and so temperature remains unchanged.
  17. A Cloudy Outlook for Low Climate Sensitivity
    Excellent post Dana. It is so sad that the data look so bad.
  18. Positive feedback means runaway warming
    Hi muoncounter- I've read one of Archer's papers, but it's been a few months and I'll reread it. I'd feel more confident in Archer's stuff if he hadn't written several joint papers with ExxonMobil chief scientist Kheshgi: ExxonMobil Contributed Papers on Climate Science
    17. Archer, D., Kheshgi, H., and Maier-Reimer, E. 1997. Multiple Timescales for the Neutralization of Fossil Fuel CO2, Geophysical Research Letters, 24: 405. 19. Archer, D., Kheshgi, H., and Maier-Reimer, E., 1998. The dynamics of fossil fuel CO2 neutralization by marine CaCO3, Global Biogeochemical Cycles, 12:259-276. 35. Kheshgi, H. S. and Archer, D. 2004. A non-linear convolution model for the evasion of CO2 injected into the deep ocean. Journal of Geophysical Research,109, C02007, doi:10.1029/2002JC001489. 13. Kheshgi, H. S., and D. Archer, 1999: Modeling the Evasion of CO2 Injected into the Deep Ocean, in Greenhouse Gas Control Technologies, edited by B. Eliasson, P. Riemer and A. Wokaun, pp. 287-292, Pergamon.
    I can see why an earth scientist might collaborate with ExxonMobil, or it's chief scientist. They undoubtedly have a monumental knowledge of geology, and an immense treasure trove of geological information. Having said that, though, Archer's estimate of the total amount of methane hydrates is on the low end of current estimates. It's a really important subject, and I'll get my information about it from sources with no known connection to ExxonMobil.
  19. Roger T. Thomes at 14:05 PM on 5 December 2010
    A Cloudy Outlook for Low Climate Sensitivity
    This is a superb article. Here is something that is not dumbed-down. There are enough facts on this topic to allow the readers to make their own conclusions.--R.T. Thomes
  20. A Cloudy Outlook for Low Climate Sensitivity
    My name's not John, but thanks dansat! Bob Guercio - I agree, the odds are not too good that Lindzen and Spencer are right. Not nearly good enough to bet the farm on.
  21. Stratospheric Cooling and Tropospheric Warming
    Daniel, This is the other cause of cooling of the stratosphere. However, this is relatively easy to understand and I do not want bring it into my writeup because it will only confuse the very complex mechanisms that cause greenhouse gases to cool the stratosphere. But yes. Thinning of the ozone layer also causes the stratosphere to cool. Bob
  22. A Cloudy Outlook for Low Climate Sensitivity
    Richard Lindzen and Roy Spencer believe that the formation of low level clouds resulting from global warming will result in a negative feedback keeping the warming in check. I just don't get it! How much statistical certainty do they have that this is going to happen? My guess is "not too much" so where is the logic in taking such a chance with our only world. Furthermore, suppose they can give a certainty which is ridiculously high, say 99.99% Does it really make sense to allow the chemistry of the planet to change so drastically considering the unknown and potentially devastating consequences? Like I said "I just don't get it!" Bob
  23. A Cloudy Outlook for Low Climate Sensitivity
    That's a heavy weight paper. Had not seen it yet. You deserve your growing reputation John! Thnx for the post! Dan
    Response: This post was written by Dana (who does deserve his heavyweight reputation as he's written most of the advanced rebuttals).
  24. Stratospheric Cooling and Tropospheric Warming
    From one following the discussion as best I can, thought I'd throw this out there:
    "The loss of ozone that has occurred in the Antarctic lower stratosphere during each spring since 1980 has led to a decrease in the lower stratospheric temperature that persists into the summer season." "Comparison of the summer temperatures in the NH and SH indicates a distinctive offset beginning around 1980. The increase in temperature near the SH summer mesopause has implications for the presence of polar mesospheric clouds." "The Antarctic ozone hole is perhaps the largest persistent perturbations to the atmosphere during recent decades. As shown here, the climate impacts of this anthropogenic change extend into the upper mesosphere. As the ozone recovers in upcoming decades, we expect to see shifts in the SH summer mesopause that bring it closer to that in the NH."
    From a science news article in Science daily; free copy of source study available here. A good chunk of the study goes over my head, like much of this thread. But these caught my eye (eye-candy, heh-heh): and If this was discussed already here, my apologies. The Yooper
  25. 2009-2010 winter saw record cold spells
    Muoncounter - I'm talking about the cold winter UK, in particular, being a regular occurrence, based on changes in the Arctic Oscillation. Not the "but there's record cold in Wagga Wagga" or whatever line the skeptics cling to. Sure it's likely to be a transient phase (the rest of the world will still be getting warmer) but I expect a similar future break-down in the circum-polar winds around Antarctica (Southern Annular Mode) will lead to similar outbreaks of cold weather. Living in New Zealand, that may affect me personally, but I probably won't be around when that happens.
  26. 2nd law of thermodynamics contradicts greenhouse theory
    #299: "nonsensical claim that planetary albedo is irrelevant to temperature" We went through a week or so of back-and-forth on the Chaos theory and global warming thread over 'climate calculators' that show specifically how albedo influences temperature. Seemed like a no-brainer at the time.
  27. The human fingerprint in the seasons
    #69: "It isn't exactly what I was expecting." When you do mean:66 after doing every:12, aren't you averaging 66 years? Cutting back even to a 30 year mean gives a cleaner break between NH summer and winter; SH summer and winter are overlain.
  28. Stratospheric Cooling and Tropospheric Warming
    Bob @133, this is correct, and I must have misunderstood what you where asking. My claim was only about the stratosphere which will (I believe) reach a steady state very quickly given constant inputs. Whether "very quickly" is a few month or a couple of years I'm not sure. @144, I believe this is correct, with motion of the whole molecule contributing to temperature, while vibration contributes to heat capacity. I am, however, not sure. In passing, Joe Blogg's first paragraph @146 is a brilliantly succinct explanation of optical depth as related to this issue. Regarding your furture article, in a topic this subtle, I suspect it would be better to write an advanced version first, and only post a basic version once the advanced version is up. When you write a basic article, you may be able to do something along the lines of comment by Nullius in Verba at Science of Doom. Doing this, I would not treat the temperature profile as a rigid bar, but rather treat the stratosphere seperately from the troposphere. Essentially, you would be appealing to the not often commented upon fact that in the presence of a negative lapse rate, greenhouse gasses cool rather than warm.
  29. The human fingerprint in the seasons
    @69, I don't particularly like that analogy because blankets work by limiting convection. As such they can have very low emissivity and their final radiant energy can still be much less than the initial radiant energy of the body covered. However, going with the analogy, it is more accurate to consider a blanket partially covering a cold blooded animal. Once a steady state is reached, there will be less energy released per unit surface from the blanket than there is from the exposed body, or there was from the exposed body before being covered.
  30. The human fingerprint in the seasons
    Chris G #67, you may be failing to consider that the troposphere is optically thick in the 15 micron (CO2) band, while the stratosphere is optically thin. Because the troposphere is optically thick, if you increase CO2 the net outgoing radiation will stay relatively constant but originate slightly higher in the atmosphere. (The increased altitude will mean the source CO2 will be slightly cooler, resulting in a slight reduction in outgoing CO2.) In contrast, because the stratosphere is optically thin, absorption will approximate to the Beer-Lambert law, so doubling CO2 will approximately double absorption and emission. The effect of this depends on the difference between tropospheric and stratospheric temperatures. If the stratosphere were cooler than the upper troposphere by an amount greater than the change in temperature at the effective altitude of radiation for the troposphere, then the effect would be to warm the stratosphere. Otherwise the effect is to cool it. More importantly, doubling CO2 concentration will double the amount of energy absorbed by CO2 in collisions; and double the amount of that collisional energy radiated away by CO2. A significant source of that energy is UV radiation absorbed by ozone. Because, with higher concentration, the CO2 would be radiating away that energy more efficiently, the stratospheric temperature will drop to reestablish a steady state. I believe this to be a larger effect than the first one. I have discussed this in more detail on the Stratospheric Cooling post on this site, particularly at comment 83 and comment 120.
  31. 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
  32. 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.
  33. 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.
  34. 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.
  35. 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.
  36. 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.
  37. 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)
  38. 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.
  39. 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.
  40. 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
  41. 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.)
  42. 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.
  43. 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.
  44. 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.
  45. 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.
  46. 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
  47. The human fingerprint in the seasons
    The prescription medicine would still be detectable through multiple methods. Historical solar irradiance changes are also detectable.
  48. 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
  49. 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.
  50. 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

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