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Bob Guercio at 07:45 AM on 4 December 2010Stratospheric 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 -
Bob Guercio at 07:24 AM on 4 December 2010Stratospheric 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 -
Philippe Chantreau at 07:23 AM on 4 December 2010A 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. -
Bob Lacatena at 07:22 AM on 4 December 2010The 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. -
scaddenp at 07:00 AM on 4 December 2010We'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. -
Ned at 07:00 AM on 4 December 20102nd 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. -
scaddenp at 06:53 AM on 4 December 2010Renewable 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. -
Joe Blog at 06:46 AM on 4 December 2010Stratospheric 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. -
Billhunter at 06:44 AM on 4 December 2010A 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. -
Bob Guercio at 06:39 AM on 4 December 2010Stratospheric 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 -
Joe Blog at 06:30 AM on 4 December 2010Stratospheric 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. -
Ned at 06:23 AM on 4 December 20102nd 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! -
Bob Guercio at 06:21 AM on 4 December 2010Stratospheric 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 -
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. -
Ned at 06:15 AM on 4 December 20102nd 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. -
Tom Dayton at 06:14 AM on 4 December 20102nd 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. -
h pierce at 06:12 AM on 4 December 2010The 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. -
Ned at 06:10 AM on 4 December 20102nd 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. -
damorbel at 05:50 AM on 4 December 20102nd 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. -
Bibliovermis at 05:50 AM on 4 December 20102nd 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). -
Tom Dayton at 05:47 AM on 4 December 20102nd 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. -
damorbel at 05:38 AM on 4 December 20102nd 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. -
actually thoughtful at 05:31 AM on 4 December 2010Renewable 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. -
Albatross at 05:11 AM on 4 December 2010A 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.
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Tom Dayton at 04:51 AM on 4 December 20102nd 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. -
Bibliovermis at 04:47 AM on 4 December 2010Renewable 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. -
muoncounter at 04:42 AM on 4 December 2010The 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'? -
Tom Dayton at 04:41 AM on 4 December 20102nd 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. -
Albatross at 04:35 AM on 4 December 2010The 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. -
actually thoughtful at 04:20 AM on 4 December 2010Renewable Baseload Energy
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TOP at 04:19 AM on 4 December 2010The 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. -
Rob Honeycutt at 04:18 AM on 4 December 2010Renewable 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. -
damorbel at 04:16 AM on 4 December 2010Stratospheric 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? -
Billhunter at 04:12 AM on 4 December 2010A 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. -
damorbel at 04:06 AM on 4 December 20102nd 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? -
damorbel at 04:01 AM on 4 December 20102nd 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. -
Paul D at 03:56 AM on 4 December 2010Stratospheric 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. -
muoncounter at 03:54 AM on 4 December 2010We'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? -
Paul D at 03:50 AM on 4 December 2010Stratospheric 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. -
michael sweet at 03:46 AM on 4 December 2010Renewable 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. -
Albatross at 03:41 AM on 4 December 2010The 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. -
Joe Blog at 03:40 AM on 4 December 2010Stratospheric 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) -
Tom Dayton at 03:33 AM on 4 December 20102nd 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. -
Tom Dayton at 03:32 AM on 4 December 2010It'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. -
Albatross at 03:23 AM on 4 December 2010The 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. -
Tom Dayton at 03:21 AM on 4 December 2010The human fingerprint in the seasons
Thank you, CBDunkerson and Tom Curtis, for your explanations. -
Rovinpiper at 03:11 AM on 4 December 2010It'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? -
Karamanski at 03:05 AM on 4 December 2010The 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? -
Ned at 03:05 AM on 4 December 20102nd 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. -
Tom Dayton at 02:55 AM on 4 December 2010The human fingerprint in the seasons
I agree with CBDunkerson: The feedbacks will follow the forcings.
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