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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 102501 to 102550:

  1. Spaceman Spiff at 10:21 AM on 4 December 2010
    Stratospheric Cooling and Tropospheric Warming
    A point of clarification to my last post (#113): Yes, light emitted by CO2 in the stratosphere is escaping upward, but the low gas density there makes it a weak emitter (except near the center of the band at 15 microns) compared to the light emerging from the troposphere via CO2. In some ways, Earth's stratospheric properties and spectrum are much like those of the Sun's chromosphere, that lies just above its photosphere.
  2. Spaceman Spiff at 10:06 AM on 4 December 2010
    Stratospheric Cooling and Tropospheric Warming
    Bob Guercio @105 et al.: There are many mechanisms that populate the upper level of a radiative transition. One is by absorbing a photon having (virtually) that wavelength. But another possibility is collisional excitation. If the collision rates (gas density) aren't too large relative to the rates of radiative decay, then the collisional excitation has a chance to radiatively decay, rather than redistributing the energy back out into the thermal pool of gas due to a subsequent collisional de-excitation. So the thermal energy of the gas is converted into radiative energy -- and if that radiative energy escapes, this is a net cooling process. This is what is meant by a "net emitter". The point is that with exception of the CO2 transitions lying near the very strongest ones near 15 microns, the stratosphere is largely transparent to radiation from below (in particular, that which arises in wavebands corresponding to transitions in C02). Run the default model from David Archer's website (70 km, looking down), linked within the OP. See that sharp reversal in the spectrum within the center of the CO2 band? That light is emerging from an effective "photosphere" that lies within the stratosphere. Nearly all of the other light you see in that spectrum, including that within the C02 band is emerging from an effective photosphere somewhere within Earth's troposphere (but in the 800-1200 cm^{-1} spectral region it's emerging mainly from near Earth's surface, excepting the O3 trough near 1050 cm^{-1})-- and passes largely unscathed through the stratosphere. The stratosphere emits escaping radiation at a rate (that's the cooling rate) that is balanced by the energy deposited via absorption of short wavelength solar radiation by O3 and O2, resulting in molecular dissociation (that's the heating rate). One of the most radiatively active gases in the stratosphere is C02. Increase its abundance, and the cooling rate will exceed the heating rate until a new (lower) equilibrium temperature is reached.
  3. actually thoughtful at 09:52 AM on 4 December 2010
    Renewable Baseload Energy
    So, to support my claim that I am a greenie who is just fine with higher electric prices, what happens if we use LCOE's most expensive energy the evil photovoltaics? I live in the state of Arizona. Our warm, fuzzy, lovable profit-driven electric monopoly charges us $.14/kwh (take the bill total, divide by the kwh used). Of that cost, 46% is fuel, the rest is "not fuel". So if my baseload power averages 110/unit (using figures above (mine are probably higher - we are still paying for the Palo Verde nuclear plant built in the 1970s & 1980s - the most delayed, most expensive electricity in the history of the universe (not that I am bitter))). So, using the figures above solar PV* (the most expensive way to get electricity) costs 396.1/unit, then to switch to all PV, my electricity bill would go from 78.78 (typical (and actual) electricity bill) to 127.62 (396.1/110*45%*78.78)/month. $51 a month or 612 bucks a year to avoid climate change. Does anyone else see this as a bargain? I pay more for that to insure my home, health and automobile (each). * Now it is obvious that RIGHT NOW we can't switch to all PV. Both logistically, and due to grid-level storage. And we wouldn't use all solar PV, we would use a mix (including nukes), so while my renewables-only cost is WILDLY inflated, I will leave it as is to easily cover the grid-level storage issue. But that should pretty much kill the solar is too expensive argument. It fails because it isn't true (a painful death, surely). Oh, and the zombie-like follow on argument - energy increases apply to ALL sectors of the economy - everything, everywhere: 78.78 is 2.3% of my monthly budget. So factor in a one time economic inflation of 2.3%. Still cheap by any rational standard.
  4. A basic overview of Antarctic ice
    Hi Bill, "..... it would seem the winner is no statistically significant change." Umm, no. I'm afraid that you seem to have completely missed the point of that statistical analysis exercise. Anyhow, the graph @89 is the net result of all the changes/processes and it is showing a distinct downward trend in global sea ice since about 2001. Global sea ice coverage and volume is down. Continental glacier and ice sheet volume is down. Greenland ice sheet volume is down. Antarctic ice sheetvolume (mainly WAIS)is down.
  5. The human fingerprint in the seasons
    To this end, I played with some graphs at Wood for Trees. I got this far before running out of time. Four plots of January,July versus Southern, Northern hemispheres. Ran out of time before figuring out how (or if it is possible) to aggregate between series, but the test is basically: "Are red and purple rising faster than blue and green?" I believe the answer is "yes". I smoothed over best-guess of the time interval for 6 solar cycles.
  6. actually thoughtful at 09:14 AM on 4 December 2010
    Renewable Baseload Energy
    I looked deep into my crystal ball and determined the following: *In 2011 the levelized cost of nuclear will include a 25% higher overnight cost. *In 2011 the levelized cost of solar PV will include a 25% LOWER overnight cost. You can look into my crystal ball too! http://www.eia.doe.gov/oiaf/beck_plantcosts/index.html (click on the table 2 link) So now we can debate the rate of change and burn up another 200 or so messages. My take away is that DOE is having to eat a little bit of crow for being so far from reality (but all you renewable haters good news for you, too: geothermal doubles and burning methane out at the dump triples!) Beyond the crystal gazing above to support my "doubt the DOE" theme - riddle me this: Why does it cost almost DOUBLE to run a solar thermal plant compared to running a nuclear plant? Yes, we wash the panels (with a machine). Given the downside to things going wrong, wouldn't you almost hope it cost more to run the nuke? What are they doing with all that O&M money down at the ST plant? I might enjoy burger and beer night over at the ST plant - sounds like they have the funds to do it right!
  7. Stratospheric Cooling and Tropospheric Warming
    Re Daniel 109 Thanks that is the one.
  8. Stratospheric Cooling and Tropospheric Warming
    I understand the points Tom Curtis was making and I agree I made a mistake in 88. I'm thinking that in Toms scenario, because all the Suns energy would get to the surface, like the Moon, the surface would get hot (like the Moon) it would also emit a lot of radiation, which would go straight back out to space. However assuming the atmosphere was able to warm by conduction, the atmosphere would get warmed at the surface, and that warmed atmosphere would behave roughly as Tom described (lapse rate as described). The question would be how warm? I guess the warmed atmosphere would help to increase the temperature of the surface which would emit more, thus removing energy and keeping a balance between incoming and outgoing energy. Apologies that it took so long for me to get my brain around it.
  9. Stratospheric Cooling and Tropospheric Warming
    It comes from this site. The image I wish to refer to is the 4th from the top of the page Heat loses and gains in the atmosphere This is the site if the link does not work http://lasp.colorado.edu/~bagenal/3720/CLASS14/14EVM-5.html
    Moderator Response: [Daniel Bailey] You've been including an extra / at the end of the URL. Make sure you use the preview function before submitting; formatting errors in URLs and posting of images are by far the most common errors in posting. Most would have been caught by previewing.
  10. Stratospheric Cooling and Tropospheric Warming
    Re: mars (108) This one?
  11. Stratospheric Cooling and Tropospheric Warming
    Hmm I don't seem to be able to post the image It comes from this site. The image I wish to refer to is the 4th from the top of the page Heat loses and gains in the atmoshere
  12. 2nd law of thermodynamics contradicts greenhouse theory
    And took hits for not observing the Skeptics' "Code Duello" The Yooper
  13. 2nd law of thermodynamics contradicts greenhouse theory
    Ned @ 290 - there's always the exception to the rule, albeit very minor, BP waded into Ken Lambert a few weeks back over a "theoretical observed" comment.
  14. Stratospheric Cooling and Tropospheric Warming
    The image above shows how the Ir emission from of CO2 and other GHG produces cooling in the stratosphere. This suggests that Bobs explanation is inadequate.
  15. actually thoughtful at 08:48 AM on 4 December 2010
    Renewable Baseload Energy
    On to this post: Peter Lang version 1 "Better to stick with Levelised Cost of Electricity (LCOE)." But WAIT, read on in this post Peter Lang version 2 "Gemasolar (Spain) ... Cost per average kW = $34,587/kWy/y For comparison nuclear = $4,500/kWy/y" So it seems that LCOE is what one ought to do, but if a particular renewable project exceeds the budget - let's focus on that instead for the rhetorical points. For the record - I've already pointed out why and how the DOE is slanted in favor of existing, polluting industry and against renewables. But even using their data, the results speak for themselves. (no subsidies, no carbon pricing - the free market in its current busted state) [2008$/megawatt hours] least to most expensive: Natural gas (NG) advanced combined cycle 79.3 NG combined cycle 83.1 coal 100.4 advanced coal 110.5 Biomass 111 NG advanced CC with CCS 113.3 Geothermal 115.7 advanced nuclear 119 Hydro 119.9 NG advanced combustion turbine 123.5 advanced coal with CCS 129.3 NG conventional combustion turbine 139.5 Wind 149.3 Wind-offshore 191.1 Solar thermal 256.6 Solar PV 396.1 This is from the DOE, by way of wikipedia - you can trace out the veracity yourself if you want. I trust wikipedia to cut'n'paste the DOE data. clickable link - check out UK and by energy source down below the DOE bit - DOE is NOT the only possible source of credible data I suggest anything within 10% is basically equivalent. I don't know what overnight (OK, now I do $3,902/kW) or all in cost they used for nuclear. So using the cost ONLY, but avoid carbon (and claims about future efficacy are accepted (like advanced nuclear is cheap, CCS works, etc)). We would, as rational optimizers of baseload power avoiding fossil CO2, choose: Biomass 111 NG advanced CC with CCS 113.3 Geothermal 115.7 advanced nuclear 119 Hydro 119.9 Wind 149.3 Wind-offshore 191.1 Solar thermal 256.6 Solar PV 396.1 [As a certified "greenie" I am able to state the obvious - electricity is too cheap because it does not factor in the cost of CO2 - once you do that, you don't just re-arrange preferences on the chart above - the chart itself will change.]
  16. The human fingerprint in the seasons
    Doh, regarding my first point, I now see that the data are for NH only. So, my concern is moot. However, I think it would make for a stronger case if SH temps were included as well.
  17. The human fingerprint in the seasons
    A few things I've noticed: #12 TIS says: "There is no time when the Earth is in winter or in summer." This is a valid concern. It would be pretty easy to aggregate summer as NH June-July-August and SH December-January-February, and vice versa for winter. However, I can't tell if this has been done within the spreadsheet since I don't see a column for hemisphere. TIS's comment about orbital obliquity is of dubious merit; it just doesn't change much over the course of decades. That effect operates over millenia. #39 Tom Curtis: "Fourth, water vapour is largely confined to the troposphere, so the water vapour feedback will not result in stratospheric cooling. " I agree with other points, but I'm not sure I'm following this. Most of the atmosphere in general, including CO2, is within the troposphere. The average height of emission of a photon to space is around 5-6K, and the tropopause is mostly above that. My understanding is that any GHG effect results in tropospheric warming and stratospheric cooling. The atmosphere is heated from above by whatever SW radiation is absorbed and it is heated from below by whatever LW radiation is absorbed, plus conduction. The tropopause exists where these balance each other. #36 Sphaerica, An excellent point regarding water vapor and climate sensitivity. You can't have it both ways. #45 TOP: "For 6 months out of the year the solar radiation input and hence the effect of any GHG on blocking radiation to space there is minimal to non-existent." This is wrong at the conceptual level. The surface of the earth is above 0K at all times and at all locations; therefore, it is always emitting radiative energy at all times and at all locations. See Planck's Law. General comment regarding comments on water vapor versus CO2 effects: The phase state diagram of H20 is different from CO2. Humidity varies a lot by both altitude and latitude because the temperature and pressure where it precipitates is common within our atmosphere. CO2 precipitates at temperatures and pressures not common within our atmosphere; so, it varies a lot less with altitude and latitude. I'm pretty sure one could define different warming, 3D spatial signatures to be expected dependent on which was changing more. However, since the two are linked via the physical properties of the system, it is not clear to me how the data could be unobfuscated. (Hmm, on another read, I see that #4,22 Mike has already made this point, and asked the same question I'm leading to.)
  18. Renewable Baseload Energy
    Re: All concerned parties The reason I stepped in and made nuclear off-topic on this thread was to try to prevent what we saw happen on the other thread (and I was asked by a commenter to do so). As has been pointed out, this action (policement by moderation) had only limited effect. If I may suggest a different tactic: the community active on this thread simply ignore any and all comments from Peter Lang that you disagree with. In effect, the problem goes away. This thread belongs to all of you. Unite, and take ownership of it. The Yooper
  19. Stratospheric Cooling and Tropospheric Warming
    Joe, There are two situations. One is what is going on now. The stratosphere is cooler and the earth is gaining more energy than it is emitting. This cannot go on forever. Let's say we stabilize the CO2 level to what it is now. The earth continues to heat and in a few decades the energy entering the earth will be the same as that leaving. That is the second situation. And there too, the stratosphere will be cooler than what it was before more co2 was put into the atmosphere. We have to be clear which situation we are talking about in order to understand each other. My blog that was posted by John Cook addresses only the steady state solution. Bob
  20. Stratospheric Cooling and Tropospheric Warming
    Joe, That paper is heavy. Can you explain it in your own words or point to the salient portions of that paper. I'm not sure if this is going to work but I have an image on the CO2 spectrum here. If it doesn't appear, please go to the URL that you see. The spectrum is almost entirely in the IR region. So how can it be a net absorber or emitter of IR. Or is the little amount in the visible region enough to make it that. Bob
    Moderator Response: [Daniel Bailey] - Fixed HTML
  21. Philippe Chantreau at 07:23 AM on 4 December 2010
    A basic overview of Antarctic ice
    "it would seem the winner is no statistically significant change" The above graph of global sea ice anomaly shows a significant decline. One has to go back to 1988 to find a positive anomaly comparable, albeit smaller, to the negative anomalies experienced on a regular basis in the past 10 years. And the baseline includes all years to 2008. Global sea ice area coverage is decreasing.
  22. The human fingerprint in the seasons
    39 (Tom Curtis), When you say:
    direct solar heating would make days hotter than night, summers hotter than winter, and tropics hotter than the poles, while to a first approximation, the water vapour feedback would have the reverse effect. Because the initial forcing and feedback have effects opposite in sign, they would cancel each other out (to a first approximation), thus resulting in no signal.
    I'm not entirely sure that this would be true. It would be a question of degree (i.e. is one strong than the other), and I think the H2O forcing would stand out, although not to the same degree as with solar versus CO2. To be a little more specific, if we assume a 3C total warming from a doubling of CO2, which itself contributes 1C to the 3C, then feedbacks (primarily H2O, or follow-on CO2, but also including changes in albedo due to ice retreat) are responsible for roughly 2C of warming. This implies that a change in insolation which causes 1C of warming will in turn cause 2C of feedback (primarily in the form of GHG). As a side note, as the topic of different forcings has come up often of late, I'm finding myself annoyed at the previously convenient definition of climate sensitivity in terms of doubling of CO2 -- it implies that CO2 is necessary, and provides no yardstick for other forcings. A definition of "X degrees of change per Y degrees from external forcing" would be more workable. Oh, well... So the GHG signal would be stronger than the insolation signal, and should stand out as described in the original post, just not to the same degree as pure GHG forcing would (by a factor of roughly 3:1). But there would be no way (without a trial run of each) to be able to tell whether what we are seeing now is or is not a result of insolation forcing (1C) + GHG feedback (2C), or GHG forcing (1C) + GHG feedback (3C). Except, of course, for the differences in stratospheric cooling, and numerous other methods not mentioned in or relevant to the original post (Dan listed a number of them), such a the need to explain why the globe somehow isn't warming from CO2 emissions if another cause were found.
    In particular, direct solar heating would result in a significant increase in humidity in the tropics, but not the poles.
    I'm not sure that this is true, either. Transport of moisture from the tropics to the poles is an important part of both climate and weather, and changes in such transport are one of the biggest dangers of a warming world (expansion of the arid subtropic zones), so I don't think a blanket statement could be made in this regard.
  23. We're heading into an ice age
    BP, the rate of change associated with YD type events is also assessed from lake records but I dont have reference handy - but read it in recent review by Wally Broecker. cjshaker - I agree that emerging from ice age, there is good evidence for very fast changes - too fast I think for modern agriculture to cope. We have too many hypotheses and insufficient data to start with total certainty the causes are but we take comfort from fact that these effects appear to only happen as climate emerges from glacial and not during interglacial, and that these appear to be hemispherical events not global events. The review in IPCC WG1, Chapter 6 on this is well worth reading.
  24. 2nd law of thermodynamics contradicts greenhouse theory
    KR writes: damorbel - The last 15-20 postings you have presented have made it increasingly clear that you do not have a firm grasp of the physics involved. That's not an insult - we all start somewhere. Yes. And I would note that, as we saw with the Evil Waste Heat Thread, the usual SkS "skeptics" are once again standing by on the sidelines. Apparently they're willing to quibble endlessly over things like UHI, who wrote what in a snippet of somebody's email, etc. But they're not willing to speak up and help address the problems with even the most appallingly confused argument coming from the "skeptic" side. As always, it turns out that "climate skepticism" is rather asymmetric around here. The unwritten rule seems to be that "No SkS skeptic shall ever publicly disagree with another SkS skeptic." IMHO that's pretty depressing.
  25. Renewable Baseload Energy
    "n New Zealand you, like Australia, have a ban on (unprintable), so we have no way of knowing if your generating system is the least cost option." Commonly believed but I as pointed out on another thread, false. The ban on nuclear-powered ships and weapons, does not extent to a ban on nuclear power. The last ministerial statement I heard on the subject ruled out nuclear on economic grounds, based Electricity Commission research, looking at small scale of electricity requirement compared to infrastructure needed to support it.
  26. Stratospheric Cooling and Tropospheric Warming
    Bob Guercio At equilibrium, how can a group of molecules be net absorbers or net emitters. Because the energy is brought into the stratosphere by O3, through UV and 9-10micron LW absorption, but emitted by co2 and h2o. CO2 does absorb some LW, but emits twice what it absorbs. I'll be the first to admit it seems counter intuitive. I did not get this until i came across this paper paper Its about variable O3 effects, but it quantifies all the radiative exchanges involving the stratosphere/troposphere very clearly.
  27. A basic overview of Antarctic ice
    Albatross at 05:11 AM on 4 December, 2010 Bill, "Please read my post @74." Tests of statistical significance may or may not return strong results. In the case of your analysis you returned statistically significant change in two different directions. The fact that you got a distribution of 3 statistically significant ice shrinkage, 1 statistically significant ice gain, and 6 cases of no statistical significant change, it would seem the winner is no statistically significant change. I suspect that if fall and spring was included the number of cases of no statistically significant change would greatly increase. Thus what is happening with ice on the planet would only be remarkable under the assumption that statistically significant change is the rule.
  28. Stratospheric Cooling and Tropospheric Warming
    Joe Blog 102 At equilibrium, how can a group of molecules be net absorbers or net emitters. If CO2 is a net absorber, that would mean it is constantly absorbing more than it is emitting. That can't be. Now ozone is different. It absorbs and emits both IR and UV. So it could absorb UV and emit IR so I guess you could say it is a UV absorber and an IR emitter in the stratosphere. But I don't believe that CO2 reacts appreciably with visible light so at equilibrium, it cannot be a net absorber or a net emitter. Bob
  29. Stratospheric Cooling and Tropospheric Warming
    Bob Guercio at 06:21 Bob, i dont disagree with much in this post, except your understanding onb the mechanisms of stratospheric cooling, O3 is a net absorber, CO2 & H2O are net emitters in the stratosphere, and they do balance. In my first comment @ 44 i linked a paper by Ramanthan and Dickenson, it quantifies the radiative exchanges between troposphere and stratosphere... the stratosphere is a net emitter to the troposphere, not the other way around.
  30. 2nd law of thermodynamics contradicts greenhouse theory
    damorbel writes: Another application of this principle is multilayer insulation Multilayer insulation stacks up reflective surfaces and is extremely effective. Good grief! Did you even read that wikipedia page you linked to? How could you not have noticed that their explanation of how multilayer insulation works is exactly the process whereby backradiation from CO2 in the atmosphere raises the temperature of the earth above what it would be in the absence of that CO2! The process that you yourself cite as "extremely effective" is the exact same process that you claim violates the second law of thermodynamics!
  31. Stratospheric Cooling and Tropospheric Warming
    As I see it: Conservation of energy must be considered at all times. At equilibrium, the energy into a system must equal the energy out. Consider a box of CO2 with infrared coming in and leaving. CO2 molecules are constantly emitting and absorbing infrared; however, at equilibrium the number of absorbers equals the number of emitters. Now imagine that the incoming IR is cut in half. Suddenly there is less IR to be absorbed and for a while there will be more emitters than absorbers until equilibrium is reached. Again, emitters will equal absorbers with less energy coming in and less energy going out than before it was cut in half. My intuitive guess would be that equilibrium occurs very quickly and at any time the stratosphere is in equilibrium. The same holds true for sunlight coming in and interacting with the ozone. Ozone molecules are constantly absorbing and emitting radiation with the amount of energy coming in equaling the amount leaving. Fortunately for us, the UV energy absorbed is at a different frequency from that emitted but for the total energy spectrum, the amount coming in equals the amount leaving. At present, more energy is coming into the earth than is leaving. This energy is being absorbed by the earth and, were the CO2 in the air to miraculously stabilize today, the earth will continue warming up for another few decades. As the temperature increases, more heat energy will leave the earth until such time that the temperature is warm enough so that the IR energy leaving is equal to the sunlight energy entering. The troposphere will be warmer and at equilibrium so that the IR energy leaving the troposphere will be the same as the IR energy entering. The IR entering the stratosphere will be the same as that leaving but the stratosphere will forever be cooler than it was before CO2 levels increased. This is because the IR spectrum leaving the troposphere is different. Even though there is the same amount of IR energy leaving, less of this energy is able to react with the CO2 in the stratosphere which keeps it at whatever temperature it is. Bob
  32. 2nd law of thermodynamics contradicts greenhouse theory
    damorbel - The last 15-20 postings you have presented have made it increasingly clear that you do not have a firm grasp of the physics involved. That's not an insult - we all start somewhere. I, like Ned, strongly suggest you go check with your local university or other institute of learning, and find out some more of the basics.
  33. 2nd law of thermodynamics contradicts greenhouse theory
    Tom Dayton writes: damorbel, at face value your statement is correct that "the absorption capacity is always equal to the emission capacity." ... at a particular wavelength. Part of the problem with damorbel's argument here is that the incoming solar radiation has a very different spectral distribution from the outgoing longwave radiation. Absorptance in the visible/near-IR is not necessarily equal to thermal infrared emissivity.
  34. 2nd law of thermodynamics contradicts greenhouse theory
    damorbel, the reflective outer surface of an inner layer of multilayer insulation does not help by reducing that layer's emission. It helps instead by reducing that layer's absorption of the radiation emitted by the next-most-outer layer--radiation that this inner layer emitted, that was returned by the outer layer.
  35. The human fingerprint in the seasons
    ATTN: muoncounter at 13:22 PM on 3 December, 2010 The wind is by far the most important mechanism that transports surface water into the atmosphere. Evaporation of water in still air is a slow process. Set out a shallow dish with water and determine how long it takes for the water to evaporate. Refill the dish to the same level and have a fan blow a gentle current of air over the water. The water level will decrease much faster in the presence of the wind from the fan. Clouds are another source of water vapor. Since they can move about freely and quickly, they can alter the local humidty --like to 100% of they bring rain or snow.
  36. 2nd law of thermodynamics contradicts greenhouse theory
    damorbel writes: So thermos (vacuum) flasks don't work this way? Care to explain how they do? The problem is that planets don't work this way. Read the rest of my comment. The point is that the incoming and outgoing radiation fluxes have different spectral distributions. A change in the visible/NIR albedo doesn't imply a corresponding change in thermal infrared emissivity. A lot of your comments in this thread seem to involve trying to analogize the earth-sun radiation balance to some object, like a thermos or asphalt or a coffee pot. With all due respect, that's not necessarily the best approach.
  37. 2nd law of thermodynamics contradicts greenhouse theory
    Re #280 Tom Dayton you wrote:- "But emission from that inner chamber is not reduced by making the outer surface of that inner chamber reflective." A polished metal outer surface is an excellent insulator, the old fashioned silver coffee pot is a a good example, the modern chrome model is just as good because it doesn't need polishing so much. Another application of this principle is multilayer insulation Multilayer insulation stacks up reflective surfaces and is extremely effective.
  38. 2nd law of thermodynamics contradicts greenhouse theory
    Consider Tom's example using one source, but objects A & B are spaced so that they receive the amount of energy described and are isolated from each other (i.e. directly opposite each other & fully obscured by the source).
  39. 2nd law of thermodynamics contradicts greenhouse theory
    damorbel, I posed my alternate scenario so you can see that the temperatures of the objects in that scenario are identical to the temperatures of those objects in CBDunkerson's original scenario. That should help you understand that photons reflected don't contribute to temperatures of the objects. Only the absorbed photons matter.
  40. 2nd law of thermodynamics contradicts greenhouse theory
    Re #279 Tom Dayton you wrote:- "1) Make both objects A and B perfectly absorptive--no reflection, in other words albedos of zero." This destroys the whole matter. If you consider the case when albedo is zero there can be no effect due to albedo and there can be no confusion arising from the influence of albedo and 2nd law of thermodynamics. "(2) Isolate A from B." Why? "3) Give object A its own radiation source--a source that sends only 10% of the radiation that CB's original source did" I think you should be more precise and define the source better. I really do not understand why you need two sources to explain these concepts.
  41. actually thoughtful at 05:31 AM on 4 December 2010
    Renewable Baseload Energy
    So on to clarifying claims: Muoncounter points out that in a capitalistic market - higher costs will result in higher end-prices, and demonstrates electricity prices are NOT higher in markets with more renewables. Peter Lang responds that pricing is complicated, very, very complicated. A notable amount of hand waving goes on, and then he concludes:"The distributors higher cost must be passed on, with profit and all the other costs, to the consumer as a higher price." Bravo! Peter Lang in fact, agree with Muoncounter and his graph of real world data invalidates all Peter Lang claims above, with dark mumblings of 5 to 20X the cost and on and on. Peter Lang himself makes this point. Now Peter Lang is right that pricing is complicated, that electricity markets are regulated to a degree (but your local, cuddly monopoly electric company, is, most likely traded on your stock exchange and if you confuse it for anything but a profit-driven corporation, you will be tragically wrong). And, given the rate of increase in renewables, we should revisit Muoncounters chart with in a few years when all the changes in renewables have had time to roll through. And, given the low amount of renewables in absolute terms, it will have a relatively small impact on the final price. But with the data available, and using Peter Lang's own logic - Muoncounters graph stands as a real world counter to the notion that renewables are too expensive to use for baseload power.
  42. A basic overview of Antarctic ice
    Bill, Please read my post @74. Note that, with the exception of July (the austral winter), the trends in the Antarctic sea ice are not statistically significant for the months I looked at. The trends in the Arctic ice are, and more importantly the loss is clearly accelerating, especially during the warm season. Consequently the loss of ice from the Arctic is fast outpacing any gains in Antarctic sea ice. This is probably in part because of polar amplification over the Arctic. So, the greatest loss in Arctic ice is during the warm season when insolation (incoming solar radiation) is high, but the impacts of the ice loss linger into winter, as is explained in the links on polar amplification that I provided. There is a positive feedback at work over the Arctic and it is linked to a lowering of albedo stemming from ice loss (including sea ice). The above situation explains why the trend in sea ice coverage is negative. Finally, multiple, independent lines of evidence show that the Antarctic ice sheet is losing ice, especially the WAIS. Additionally, trends in warm season sea ice coverage in the vicinity of WAIS are also down, and the loss of ice in the Bellinghause and Amundsen seas is critical, because the impacts of the loss of the sea ice which used to buttress ice sheets and glaciers has already been observed.
  43. 2nd law of thermodynamics contradicts greenhouse theory
    damorbel, a vacuum flask has an inner chamber inside an outer chamber. If the inner chamber is filled with a hot liquid, emission from that chamber can be reduced by making the inner surface of that inner chamber reflective. But emission from that inner chamber is not reduced by making the outer surface of that inner chamber reflective. Once that radiation has escaped from the inner chamber, it must get through the walls of the outer chamber, which can be reduced by giving the inner-facing walls of that outer chamber a reflective coating; that bounces the radiation back from the outer wall into the gap between the inner and outer chambers.
  44. Renewable Baseload Energy
    I suppose that I'm a fence-sitter on nuclear power. It's a matter of cynicism rather "omg teh radiations!", in much the same way that I would be cynical about handing a running chainsaw to a 12 year old with ADHD. In the previous thread with Lang, I presented a "window on government" report to counter his claims about nuclear vs renewable subsidies. I was accused of intentionally misleading and so have had no desire to contribute to a thread that he is a primary participant in. My concerns about nuclear power are that the safety & maintenance protocols will be neglected or outright compromised in the race for the bottom line, and waste maintenance protocols that call for intensive monitoring & military patrol over an initial period of 300 years (hence the ADHD comment). I find it quite ironic that renewable baseload energy is dismissed with "if it's so great why hasn't it been done yet?" by the same people touting spent fuel reprocessing and thorium reactors.
  45. The human fingerprint in the seasons
    #45: "The heat causing melting of polar ice has to come from elsewhere. ... The source of the heat doesn't have to be in the arctic areas." As long as you agree that the greenhouse-trapped heat is melting Arctic ice, what difference does it make where the heat comes from? I guess I misunderstood your prior 'greenhouse warming is primarily a land-based effect'. "Sea ice formation is from under the ice." How do you figure that? From wikipedia: In calm water, the first sea ice to form on the surface is a skim of separate crystals which initially are in the form of tiny discs, floating flat on the surface ... In rough water, fresh sea ice is formed by the cooling of the ocean as heat is lost into the atmosphere. Are you referring to 'anchor ice'?
  46. 2nd law of thermodynamics contradicts greenhouse theory
    damorbel, at face value your statement is correct that "the absorption capacity is always equal to the emission capacity." But I think you meant something else--something incorrect. Here is a correct rephrasing: The reflected photons are irrelevant to the absorption and emission of the object, and therefore are irrelevant to the temperature of the object. The only contributors to the temperature of an object are the photons absorbed and the photons emitted. You will get exactly the same temperatures, absorptions, and emissions of objects A and B that you get in the scenario that CBDunkerson described, in this different scenario: (1) Make both objects A and B perfectly absorptive--no reflection, in other words albedos of zero. (2) Isolate A from B. (3) Give object A its own radiation source--a source that sends only 10% of the radiation that CB's original source did. Object A is absorbing 100% of that, so Object A is absorbing the same radiation (and therefore the same energy) that it was getting in CB's original scenario. (4) Give object B its own radiation source--a source that sends only 75% of the radiation that CB's original source did. Object B is absorbing 100% of that, so Object B is absorbing the same radiation (and therefore the same energy) that it was getting in CB's original scenario. (5) The temperature of Object A will be lower than the temperature of Object B.
  47. The human fingerprint in the seasons
    TOP @45, You may have a point regarding 1980. Tamino has undertaken some analysis and concluded that the anthro warming signal emerged circa 1975. See here [the title is a little confusing, but the text clarifies everything] and here.
  48. actually thoughtful at 04:20 AM on 4 December 2010
    Renewable Baseload Energy
    @ The problem is that Peter Lang's comments, to casual readers, APPEAR to be valid. Which is why I take the time to debunk his claims. Peter Lang - you have chosen to ignore my posts, which provide rational, fact based responses to your claims. That failure is glaring and speaks volumes as to the credibility of the arguments you present. It is your choice to respond or not, of course. Some people find my in-your-face style of facts and logic to much to deal with. My approach doesn't leave much room for ideology or beliefs, relying as it does on reality, facts and logic. All of that said, as Ned eloquently presents above - both nuclear and renewables have a role in the future, non-carbon baseload supply. So I disagree with the idea that we shouldn't talk about nuclear in a renewable baseload energy thread (tightly interpreted, yes nuclear is not renewable but it is like balancing a three legged stool on two legs, you end up wondering what is going on with the (missing) 3rd leg).
  49. The human fingerprint in the seasons
    @Daniel Bailey Why I would say that Figure 1 shows global warming starts in 1980 is based on the premise of the author's argument, that winter warming increasing faster than summer warming is a fingerprint of AGW. The winter warming shift occurred in the 1980s. Prior to that there was a summer shift, again according to the author's premise, showing primarily solar warming. If AGW had started in the mid 1800s then this shift should have been there all along to some extent. @muoncounter The contribution of the Arctic and Antarctic to warming is minor compared to areas nearer the equator. For 6 months out of the year the solar radiation input and hence the effect of any GHG on blocking radiation to space there is minimal to non-existent. The heat causing melting of polar ice has to come from elsewhere. Sea ice formation is from under the ice. It melts because there is heat input. The source of the heat doesn't have to be in the arctic areas. It can be transported there.
  50. Renewable Baseload Energy
    You know, there is one part that I think is missing in the baseload discussion here (it's a long thread so I might have missed something). With large amounts of nuclear providing baseload you end up running spin reserve off peak. You can't just switch off a nuclear power plant when the country goes to sleep. Well distributed wind and solar actually better mimmic power demand cycles. We are, still for the most part, a diurnal species. Nuclear is excellent at producing electricity at a constant rate. Wind and solar are excellent at producing electricity in a cyclical pattern. All of the grid scale storage discussed in the original article here apply equally well to the utilization of nuclear's spin reserve off-peak as it does to mitigate the intermittency of renewables. Again, it's going to require pulling out all the stops to address CO2 and climate change. There is no silver bullet solution.

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