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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 102351 to 102400:

  1. 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).
  2. 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.
  3. 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.
  4. 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.
  5. 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.
  6. 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.
  7. 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.
  8. 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'?
  9. 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.
  10. 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.
  11. 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).
  12. 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.
  13. 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.
  14. Stratospheric Cooling and Tropospheric Warming
    Re #96 Bob Guercio you wrote:- ".layer of the earth's atmosphere located above the troposphere and below the mesosphere." That's a rather broad definition, don't you think? A bit like beauty, in the eye of the beholder! Surely the UV absorption, the temperature inversion and the lack of convection are all relevant matters when considering the thermal properties of the stratosphere?
  15. A basic overview of Antarctic ice
    Daniel Bailey at 10:44 AM on 1 December, 2010 Do you not understand? "The point of the post is that focusing on Antarctic Sea Ice (ASI) is a strawman argument. ASI offers little contribution to the global energy budget, unlike changes in Arctic Sea Ice cover. Which then melts away come Antarctic summer." The problem as I see it is the anomaly for sea ice in the southern hemisphere is positive (more sea ice) and that is the case for all seasons. The antarctic sea ice expands and contracts just like the arctic sea ice does. This argument seems to speculate that when and if antarctic sea ice does melt totally in the summer continued loss of arctic sea ice will become more important as it continues to melt closer to the pole. But that doesn't seem too likely since antarctic sea ice is expanding rather than contracting and in the mean time the ice at both poles seasonally expand and contract, providing whatever effects that shrinking and expanding sea ice provides. So once again we are not talking science or real ice loss. The above argument argues that arctic sea ice will become more important than antarctic sea ice as the crystal ball is being read. One would expect that if the crystal ball were correct it would be more consistent with the theory that both poles were losing sea ice. But that is the nature of complex systems; simple explanations seldom suffice.
  16. 2nd law of thermodynamics contradicts greenhouse theory
    Re #275 Ned you cite my post:- "Highly reflective materials (high albedo) heat up slowly and cool down slowly in the absence of input; an example of this is a thermos flask with its highly polished surfaces." Then you write:- "Look, this is just wrong. It really is." So thermos (vacuum) flasks don't work this way? Care to explain how they do?
  17. 2nd law of thermodynamics contradicts greenhouse theory
    Re #273 CBDunkerson you write:- "Object A reflects 90 units and absorbs 10. That 10 absorption heats up the object until it is emitting 10 units. At that point the 90 units reflected + 10 units emitted equals the 100 units incoming and the object is at equilibrium. Object B reflects 25 units and absorbs 75. That 75 absorption heats up the object until it is emitting 75 units. At that point the 25 units reflected + 75 units emitted equals the 100 units incoming and the object is at equilibrium." Fair enough. But then you write:- "At equilibrium object A is emitting 10 units of energy and object B is emitting 75 units. Object B is thus much hotter than object A. Albedo has a direct and obvious impact on temperature." 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.
  18. Stratospheric Cooling and Tropospheric Warming
    Re my last comment. Actually your example @94 was roughly correct, but I was forgetting that most of the energy would be reflected/emitted back to space through the transparent atmosphere. A small amount of energy would warm up the atmosphere via conduction. Probably only close to the surface though.
  19. We're heading into an ice age
    #145: "it takes several millennia for carbon dioxide to get enclosed in Antarctic ice." How is that physically possible? "On average, the transformation of névé into glacial ice may take 25 to 100 years." Once the ice is fully frozen, why would there be any further aging of the air? How credible are these reported age discrepancies between ice age and air age?
  20. Stratospheric Cooling and Tropospheric Warming
    Tom Curtis@94 Actually thinking about it, if the atmosphere was 'transparent' to electromagnetic radiation but the surface wasn't, then the electromagnetic radiation reflected and emitted by the planets surface would go straight back out to space! Basically it would be similar to the Moon, but with a small amount of energy heating the atmosphere via conduction. So, yes my example was wrong, but so is your account. Goodness, I was really wondering where all the energy was going. But your fictitious model still obeys some basic laws.
  21. Renewable Baseload Energy
    Peter Lang first posted on this thread on post 177. Since that time he has made fully one third of the posts and the remainder of the posts are replies to him. He previously hijacked the "what should we do about renewable energy" thread in a similar fashion. His posts contain many false and misleading assertions. He does not treat others with respect. His posts on other blogs have been linked and shown to be strawmen and trolling. Can anything be done about this type of behaviour? I found this thread useful and enjoyed it (without posting anything myself) until post 177.
  22. The human fingerprint in the seasons
    Hi HR, Re @26&28, "I guess a definition of a 'human fingerprint' would help". I think this is why we are speaking past each other HR, because we have different understandings of what is meant by "finger print". If I recall correctly Santer et al. coined the term "fingerprint" and have applied it to the increase in the height of the tropopause. So your objection would probably apply tho that work too? HR "The problem I have is that those two options aren't the only possibilities." Could you please elaborate or present a conceptual model (preferably with links to reputable sources) which explains the observed pattern (both spatially and in the vertical) and magnitude of the observed long-term warming trend? Braganza designed an experiment which excludes solar and volcanoes. Tom's excellent post @39 leaves you even fewer options, if any at all.
  23. Stratospheric Cooling and Tropospheric Warming
    Bob Guercio at 00:47 At what what wave lengths is the increased emission from? As i and others have stated, CO2 & H2O are both net emitters in the stratosphere(2:1), where as O3 is a net absorber(9-10 micron). So to examine this we need a little more detail. (the resolution in your graphs in the main article, make it hard to make out)
  24. 2nd law of thermodynamics contradicts greenhouse theory
    I suppose this discussion about the role of albedo on equilibrium temperature should be moved to the thread about albedo. Coincidentally, Rovinpiper just posted a question about exactly that, exactly there. I replied there.
  25. It's albedo
    Yes, Rovinpiper, changing the reflectivity of a body changes the number of photons it absorbs, thereby changing the amount of energy it absorbs. All the formulas you see for calculating equilibrium temperature depend on the energy that is absorbed, not the total of that energy plus the energy that was reflected. It will help if you think of the more elemental mechanisms that are involved. A body emits more radiative energy the hotter that body is. The body gets hotter if it absorbs more energy. But radiation reflected off the body does not get absorbed, and therefore does not make the body hotter. So the body does not radiate more energy in response to incoming radiation that it reflected. Reflected radiation might just as well never have existed, in regards to that body's temperature.
  26. The human fingerprint in the seasons
    Argus @27, "How come, then, a majority of this year's heat records are from the tropics? " Could you provide a source for this please? Assuming it is correct, I'm going to hazard a guess that the records this year in the tropics were most likely because of the fairly strong El Nino event.
  27. The human fingerprint in the seasons
    Thank you, CBDunkerson and Tom Curtis, for your explanations.
  28. It's albedo
    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 (short of perfect reflectivity where equilibrium temperature must remain undefined)? Is it not necessary to demonstrate that in order to prove that albedo or aerosol-based reflectance can influence the global mean temperature?
  29. The human fingerprint in the seasons
    In recent decades, could the upward trend in the arctic oscillation index be the cause of enhanced winter warming in the mid latitudes because a cooler stratosphere strengthens the polar vortex and the westerlies?
  30. 2nd law of thermodynamics contradicts greenhouse theory
    damorbel writes: This goes further; a planet orbiting a star is immersed in photons emitted by the Sun, the number of photons intercepted by a planet is reduced by the inverse square law but this is the only reduction, making the equilibrium temperature of a planet a function only on the Sun's (photon) temperature and the planet's distance from the Sun. The idea that planetary temperature is affected by its albedo is quite mistaken. damorbel then explains this idea further: Highly reflective materials (high albedo) heat up slowly and cool down slowly in the absence of input; an example of this is a thermos flask with its highly polished surfaces. Look, this is just wrong. It really is. If you're (understandably) reluctant to accept that from a bunch of anonymous strangers on the Internet, please just stop by whatever university is nearest to where you live and talk to someone in the physics, atmospheric science, astronomy, or earth science departments, and see if they can explain it to you. The earth receives short-wavelength radiation from the sun, and radiates away long-wavelength radiation. If the albedo of the earth increased, it will receive less short-wavelength radiation (visible, near-infrared). But this doesn't imply an immediate, corresponding reduction in outgoing long-wavelength radiation. Instead, the planet will gradually cool. As it cools, the flux of outgoing long-wavelength radiation will gradually decrease, in accordance with Stefan-Bolzmann, until incoming and outcoming radiation fluxes are once again in equilibrium, with the planet at a lower temperature.
  31. The human fingerprint in the seasons
    I agree with CBDunkerson: The feedbacks will follow the forcings.
  32. The human fingerprint in the seasons
    First, let me reiterate Sphaerica's very important point that if you accept a 40-60% water vapour feedback from increases in temperature, then you are logically committed to accepting that feedback as a result of the approx 1.2 degrees C per doubling of CO2. Given that, and given the degree of warming in the 20th century, accepting a strong water vapour feedback commits you to CO2 being the main driver of that warming. Second, if the watervapour feedback was a consequence of solar heating, it would not exhibit the same pattern as that resulting from greenhouse warming. In particular, 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. In contrast, a water vapour feedback to a green house forcing would reinforce the signal, consistent with the strong signal observed. Third, all though a water vapour feedback is identical to a first approximation, more detailed analysis reveals important differences. In particular, direct solar heating would result in a significant increase in humidity in the tropics, but not the poles. So the water vapour feedback induced from solar warming would also be stronger in the tropics than at the poles. In contrast, water vapour feedback from greenhouse forcing would be more evenly distributed, tending to reinforce the signal. So, stronger warming in the poles than tropics is a clear signal of an initial greenhouse forcing, irrespective of the additional signal from water vapour. Fourth, water vapour is largely confined to the troposphere, so the water vapour feedback will not result in stratospheric cooling. Consequently, for a solar forcing we would expect a warming stratosphere, and this signal would not be masked by a water vapour feedback. From a greenhouse forcing, we would expect a cooling stratosphere, with the signal not reinforced by water vapour feedback. The cooling stratosphere is the death knell to any theory that solar radiation has driven the twentieth century warming. Similar considerations show that the warming is not due to a reduction in aerosol albedo, nor due to a reduction in cloud albedo, nor due to variations in ocean heat content (ENSO, PDO, AMO).
  33. Stratospheric Cooling and Tropospheric Warming
    I don't know but I'll give it a swag based upon the definitions below which I ran across on the web. Note that there seems to be many definitions and I didn't explicity see the one that I am guessing at. Maybe it depends upon which layer you are talking about regardless of the chemistry or any other characteristic. Apparently atmospheres on all planets are layered and perhaps the first layer is the troposphere, second the stratosphere, third the mesosphere and fouth the thermosphere. By the way, a swag is a highly technical term. It means sophisticated wild ass guess. Bob Definitions .layer of the earth's atmosphere located above the troposphere and below the mesosphere. Definitions of mesosphere on the Web: •the atmospheric layer between the stratosphere and the thermosphere
  34. 2nd law of thermodynamics contradicts greenhouse theory
    damorbel, the law about equilibrium temperature uses only the energy that the object actually absorbs. Energy contained in photons that reflect off the object is excluded by that law. Think about it: Energy that the object did not absorb does not exist inside the object, and so cannot be emitted by the object. The object does not "need" to emit energy it never absorbed.
  35. We're heading into an ice age
    Looking at the graph of temperature in the past 420,000 years, one thing that strikes me is that although the current interglacial period appears as though it may be lengthier than some previous ones, it doesn't appear to have reached the same peak value as some of the previous one's, actually falling significantly short (at present). Of course 5 datasets isn't much to go on, and the earth has been around for many million years, not just 420,000 years. But who am I to argue?
  36. Renewable Baseload Energy
    Ned - well put. I've frequently expressed my opinion that increasing nuclear will be part of the forward energy mix. I suspect breeder reactors of some type (including thorium cycle) will be needed. But treating this issue as an Either/Or proposition, ignoring valid and honestly asked questions, pooh-poohing renewable data sources while using nuclear sources uncritically, and denigrating and insulting those you disagree with, well - that doesn't add to the discussion, or to my willingness to put up with such nonsense. Peter Lang - You've made some good points about relative costs. You've made some bad ones about site distribution of renewables and the backup load requirements of uncorrelated sites (if sufficiently uncorrelated sites are available in Australia, which I regard as an open question in the absence of a decent wind/solar survey). I just wish you would drop the arrogance. And actually add to the discussion with what information you have.
  37. Stratospheric Cooling and Tropospheric Warming
    Bob Guercio @93, I understood the stratosphere to be a region of the atmosphere characterised by an inverted lapse rate (it gets hotter with greater altitude) in which convection played almost no role in heat transfer, allowing strata of distinct temperatures to form. Based on the lapse rates observed on Venus, there is no such region on Venus. On the other hand, the article you link to, and several others I found by googling "Venus" "stratosphere" do in fact refer to Venus' stratosphere. So, are you and they using a different definition to mine, or am I missing something?
  38. The human fingerprint in the seasons
    Sphaerica #36 I think you spotted one more conflicting contrarian argument. And of course the "it´s the sun" reasoning lacks one key fact: sun´s irradiance has not been increasing for several decades, now. On the other hand, the increasing direct CO2 forcing can be calculated with established, century-old science.
  39. Berényi Péter at 01:37 AM on 4 December 2010
    We're heading into an ice age
    #143 Daniel Bailey at 00:14 AM on 4 December, 2010 Changes in CO2 and temps in the paleo record occurred much more slowly than what we are physically measuring today. We do not know that. At least the ice core record does not tell us anything about the swiftness of past changes. Or do you have other, undisclosed data sources to support your valiant claim? Here is the Historical CO2 Record from the Vostok Ice Core. As you can see the difference between Age of ice and Mean age of air in it is anywhere between 1879 and 6653 years (at depth 506.4 m and 3119.51 m respectively). Therefore it takes several millennia for carbon dioxide to get enclosed in Antarctic ice. With such a heavy smoothing the present spike or anything comparable to it is rendered invisible. In general it is a grave error to conclude from the fact you can't see an invisible thing that it does not exist either.
  40. 2nd law of thermodynamics contradicts greenhouse theory
    damorbel, I understand what you believe. I also know it is false. How you can not know it is false is a great mystery to me. If you fire identical lasers at a black iron plate and a mirror the black iron plate is going to get hotter than the mirror... no matter how long you wait. This is basic and obvious, because the mirror reflects more of the laser light and thus absorbs less energy than the black iron plate. Less incoming absorbed energy means a lower temperature at which the emitted radiation equals the incoming radiation (i.e. equilibrium point). The same is true of sunlight or any other radiation and any other matter it is striking. The lower the energy absorption rate the lower the final temperature of the object will be. Again, let's look at it mathematically; Incoming radiation: 100 units Object A reflectivity: 90% Object B reflectivity: 25% Object A reflects 90 units and absorbs 10. That 10 absorption heats up the object until it is emitting 10 units. At that point the 90 units reflected + 10 units emitted equals the 100 units incoming and the object is at equilibrium. Object B reflects 25 units and absorbs 75. That 75 absorption heats up the object until it is emitting 75 units. At that point the 25 units reflected + 75 units emitted equals the 100 units incoming and the object is at equilibrium. At equilibrium object A is emitting 10 units of energy and object B is emitting 75 units. Object B is thus much hotter than object A. Albedo has a direct and obvious impact on temperature.
  41. The human fingerprint in the seasons
    John, can you show what the summer's max temps are doing? What is the trend of the hottest days of the year? What is the prediction of AGW theory about the number of extreme hot days in the summer?
  42. Stratospheric Cooling and Tropospheric Warming
    The Ville @88, my understanding is that if the atmosphere were entirely transparent to radiation, all energy flows from or to it would take place at the surface. Therefore, it would warm until the energy flows from the surface to the lowermost layer of the atmosphere equalled the energy flows from that layer to the surface. That should be when the surface and the lower most layer have the same temperature. The rest of the atmosphere would derive its heat from the lowest layer, primarily by convection. That convection would establish the temperature profile at the adiabatic lapse rate. Hot air rising would still cool as it expands from reduced pressure, ensuring that the upper atmosphere (excluding the thermosphere) remained cooler than the lower atmosphere at all times. (The situation is a little more complex if we include heat transfer to the poles.) Even if a hot air parcel rose to the top of the atmosphere at a temperature above that defined by the lapse rate, it would prevent more heat transfers to the upper atmosphere by convection at its location, and gradually cool back to the adiabat by conduction and turbulent eddies. If such hot parcels of air were generated frequently enough, and cooled slowly enough, then the lapse rate could be less than the adiabat; except that even in this case it would be defined by the adiabat for periods of peak surface temperature. Again, please correct me where I am wrong.
  43. 2nd law of thermodynamics contradicts greenhouse theory
    Re #270 CBDunkerson you wrote:- "If albedo is irrelevant to temperature... why exactly is it that black asphalt gets hotter than white cement on sunny days? " You must not confuse 'rate of heating' with 'final temperature'. Highly absorptive materials heat up quickly because they absorb a large % of the incoming radiation. Switch the radiation off and they cool correspondingly quickly. Highly reflective materials (high albedo) heat up slowly and cool down slowly in the absence of input; an example of this is a thermos flask with its highly polished surfaces. In either case, black or shiny, the final temperature, after stabilisation from whatever the initial temperature was, will be the average of the fluctuating sunshine or whatever thermal input there is. You must see from this that, with a fluctuating radiation input, the temperature of the asphalt will fluctuate about the average temperature far more than the contents of the flask but both will have the same average temperature.
  44. The human fingerprint in the seasons
    I have to agree with HumanityRules' logic that any warming will increase water vapor, providing a strong, positive H2O GHG feedback in all cases, for all forcings which will give any warming of any sort a GHG signature. For this reason, it is difficult to apply the argument made by this post. Of course, to accept this logic, one must also accept net positive feedbacks and a higher climate sensitivity. You can't argue for this, and also argue that clouds will cause a negative feedback that will hold temperatures (and therefore H2O content) relatively constant. You also can't argue the line that atmospheric H2O content simply won't change with warming. But the correct statement should be that "solar forcing without any positive GHG feedbacks" would warm days more than nights and summers more than winters. This is of course a purely abstract statement, since any warming will introduce a positive H2O GHG feedback, and eventually a positive CO2 GHG feedback as well. It would also, I think, warm the troposphere but not the stratosphere (since the warming would not necessarily increase H2O content in the stratosphere, although that's now a "known question mark", as highlighted by Solomon 2010). But it is still a difference between CO2 and solar warming, in that CO2 will reach and actively cool the stratosphere (at least until solar warming introduces its own carbon feedbacks). So that argument stands as a distinction between CO2 and solar (or other) warming. So, in the end, one is again left with the question of what has caused the warming? AGW proponents say CO2 (which, for the record, is my stance). AGW deniers say that it is the sun, or cosmic rays, or seasonal Eurasian Leprechaun Farts, or just that we don't know, but it must be something other than CO2.
  45. The human fingerprint in the seasons
    Re: TOP (31)
    "Figure 1 shows green house warming started in 1980. Cool. "
     Why in the world would you make that conclusion? Are you just graph-mining? Or do you actually have a source for that opinion? I call a balk. The Yooper
  46. Stratospheric Cooling and Tropospheric Warming
    The Ville - 81 In addition to what you say about teaching, it sems that virtually everything in Physics depends upon ridiculously simple models. Bob
  47. The human fingerprint in the seasons
    Minor remark: The link to the data on the graph subtitles points to CRUTEM3v Northern Hemisphere, whereas the graph itself is CRUTEM3 global.
  48. It's a 1500 year cycle
    Re: cjshaker (22)
    "I think the bottom line is that climate modelers don't really understand the glacial cycle, nor how it really works."
     I have responded to this over here. The Yooper
  49. We're heading into an ice age
    Re: cjshaker This is a reply to your comment over on the 'It's a 1500 year cycle' thread: ---------------------------------------------------------------------------------------------------------- Re: cjshaker
    "I think the bottom line is that climate modelers don't really understand the glacial cycle, nor how it really works."
     And your source for that claim would be...? You may want to actually read up on models. Suggested starting points can be found here, here, here, here and here. The Yooper
  50. The human fingerprint in the seasons
    #31: "Greenhouse warming is primarily a land based effect. " Surely you would include the Arctic as a place where greenhouse warming is significant... that is the Arctic Ocean?

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