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michael sweet at 11:51 AM on 19 March 2011Those who contribute the least greenhouse gases will be most impacted by climate change
Gilles: By definition FF are limited in amount and will eventually run out. Is your contention that when that happens civilization will collapse? What will happen when the FF runs out? I think people are smart enough to find substitutes. Why don't we start now, rather than wait for the climate to be permanently damaged? Since we have already passed peak oil (you claim here that oil cannot be replaced), and the best coal deposits have been mined, your pessimism about the ability of civilization to adapt to less FF will be tested soon enough in any case. At the rate India and China are increasing their consumption, even the USA will have to cut back soon, the oil is gone. -
michael sweet at 11:35 AM on 19 March 2011Maize harvest to shrink under Global Warming
JOhnd: Why would you trial a variety that was not a top performer? To make it to the trial stage a variety must have shown promise. You still have cited only your personal opinion in opposition to peer reviewed data. Not very convincing. -
ribwoods at 11:35 AM on 19 March 2011How Suffolk County Community College students contributed to the Guide to Skepticism
John, 1) I see the smileys in Albatross's post and your response, but -- Please, don't _ever_ think of including ad hominem stuff, as some anti-AGW handouts do. (What if you drew up that speech bubble as a joke, then it accidentally got into the downloadable booklet? Mistakes do happen -- see below.) 2) While the booklet's cherry tree does have a pair of blue cherries, your cherry tree diagram in the article above has none that I can see. (I have red-green color vision deficiency ... but not red-blue color deficiency!)Response: Hmm, JPEG compression must have dulled the blue cherries.
Don't worry, I wasn't planning to use the speech bubbles (no offense, Albatross, I hope :-) -
johnd at 11:27 AM on 19 March 2011Maize harvest to shrink under Global Warming
Before my post is taken out of context, my comments above were about cereals and other crops in general, with a perspective from within Australia. -
Tom Curtis at 11:15 AM on 19 March 2011What would a CO2-free atmosphere look like?
TTTM, @93, well ignore those figures if you like. You are then left with the fact that climate sensitivity as measured over a range of cold (glacial) and warm (ie, with no polar ice caps) conditions yield similar climate sensitivities. From following posts: Luminosity is much lower because the sun was cooler in the past. In essence, as the quantity of Helium rises in the solar core, you need a hotter temperature to sustain the nuclear reaction. The hotter temperature is obtained by the shrinkage of the sun's diameter. This is a straight forward prediction of the standard solar model. It has been partially confirmed by observing other similar stars in different stages of their evolution. Google the "faint young sun paradox" for more information. With regard to carbon dioxide levels, Venus and Earth have basically the same amount of Carbon, but where most of venus' carbon is in the atmosphere, most of Earth's is in carbonate rocks. So there is unquestionably enough carbon on Earth to have a 66% CO2 atmosphere, or even a 90% CO2 atmosphere. Getting that much CO2 into the atmosphere is, however, considered to be a problem still in need of resolution. -
Utahn at 11:14 AM on 19 March 2011Those who contribute the least greenhouse gases will be most impacted by climate change
Gilles, you are avoiding the question, still. I see this has been a waste of time, take care. -
Rob Honeycutt at 11:11 AM on 19 March 2011Those who contribute the least greenhouse gases will be most impacted by climate change
Gilles... Why is it so difficult to comprehend that there are viable solutions to FF energy? I'm always left curious what the resistance is. -
johnd at 11:02 AM on 19 March 2011Maize harvest to shrink under Global Warming
Rob Painting at 09:13 AM, Finally!! Firstly, it is both fortunate and unfortunate that it takes an obstinate contrarian to ignite the spark that seemed so readily apparent. Whilst it may be comforting to be rubbed or patted by others to maintain a pleasant soft glow, such treatment is unlikely to result in the spontaneous combustion that a contrarian can invoke. In Australia, we are now producing 3 times as much cereals from the same acreage as we did 50 years ago. Whilst there are many factors that contribute to that, improved plant genetics have played a significant role. Importantly, the opinion is that that same rate can be maintained over the next 50 years over the world as access to better fertilisers, pesticides and new varieties extend into areas not yet benefiting as we are. I think that many seed companies might disagree with you that significant improvements are not possible. Most such companies claim significant improvements in the yields of their latest varieties over their competitors, and all companies are regularly releasing all types of new varieties, almost annually, with details of trials conducted to support their claims. The real peer review process is conducted by the growers who with commercial, rather than academic, interest driving them will quickly determine whether a new variety offers improvement of not. Perhaps an annual inventory of the seed suppliers shelves would yield the necessary data that would allow an academic study to be undertaken, but by the time it went through the normal convoluted academic peer review process, who would find it of benefit, or even of interest. -
Gilles at 10:52 AM on 19 March 2011Those who contribute the least greenhouse gases will be most impacted by climate change
"Gilles: "Where is the problem ?" The problem is not that there are correlations with wealth and fossil fuel use, just that *you state that fossil fuels increase wealth* and don't support your statements of causation with any facts. As I asked before, do you believe correlation is causation?" No more than for climate studies - how do you compute the effect of climate changes, tell me ? but they are numerous evidence of the necessity of FF - just look at japan and imagine they wouldn't have any FF at all - the distress would be much larger. Tell me just how they would carry rescuers, food, how they would heat , build new buildings. Part of the country without oil are in a total misery - as was Haiti. -
Gilles at 10:46 AM on 19 March 2011Those who contribute the least greenhouse gases will be most impacted by climate change
les : The point was that there have been many incidents of great wealth, technical advance, etc. before oil became ubiquitous." what do you call "great wealth" ? i don't know any wealth comparable with current western countries without or before the use of oil. Michael : I'm speaking of a general correlation and a minimum amount , not of a strict proportionality constant. Impact of climate changes are ALSO statistical, I can find numerous examples where a warming does not produce any inconvenience. Electrical power is the only application that can be replaced by other sources, but in a limited amount. Although some people here seem to ignore that wind energy is intermittent, it is. And there is no interconnected network where wind energy produces more than 25 % of power. So extrapolating the fact that SOME part of the FF consumption can be spared up to zero is just plainly unjustified - although extrapolations seem to be a fashionable game. -
Rob Honeycutt at 10:42 AM on 19 March 2011What would a CO2-free atmosphere look like?
Tim... Have you watched Dr Alley's lecture yet? -
johnd at 10:22 AM on 19 March 2011Maize harvest to shrink under Global Warming
michael sweet at 23:06 PM, the trials produced yields between zero and 15Mg/Ha under optimal conditions. Please show me where in the study it is noted that they only used the results from the best performing varieties, and if that is indicated, just how many specific varieties were used out of all that were trialled to arrive at the conclusions reached. -
alan_marshall at 09:57 AM on 19 March 2011Sea level rise: coming to a place near you
While I believe sea level rise will exceed 1 metre by the end of the century, I need to point out that your map showing projected inundation of Sydney is wrong. I should know. I live there! While there are some low lying areas of alluvial fill south of Sydney Harbour, the red shaded area should be a fraction of that shown on this map.Moderator Response: [DB] Thanks for pointing that out, Alan! Dr. Weiss has indicated that future iterations of the mapping tool will have a number of improvements including superior resolution. Let's hope they are able to obtain more robust datasets from Australia! -
Tom Curtis at 09:57 AM on 19 March 20112nd law of thermodynamics contradicts greenhouse theory
Fred Staples @664: Considering the example of the steel beam, the flames will not melt the steal beam because they will (eventually if it is well insulated) heat the steal to their own temperature. At that point the black body radiation from the steel will carry the same energy as the flames preventing further warming. Applying that example to my light box model, the photons leaving the box will never have a shorter wavelength (= higher temperature) then the photons leaving it. Nor will there be more of them on average, thus conserving energy. Applying that insight to the Greenhouse effect, that means the the surface of the Earth will never be hotter than the surface of the sun (ie, the temperature of the source of the energy that warms it), and the outgoing radiation will never have a shorter wavelength than the incoming solar radiation. You will struggle to find a prohibition against the greenhouse effect from these two facts. -
scaddenp at 09:31 AM on 19 March 20112nd law of thermodynamics contradicts greenhouse theory
" So the vector sums are zero, no atmospheric forcing...no AGW. You have confirmed my position." Umm, this is about whether the GHE is consistent with thermodynamics. If it is, the adding CO2 will create forcing as KR has pointed out. (and is measured at TOA). Now the numbers on Trenberth are derived from measurement and the flux has to be consistent with temperatures. The light box discussion is about understanding why these fluxes are not a violation of 1st law. -
TimTheToolMan at 09:23 AM on 19 March 2011What would a CO2-free atmosphere look like?
OK, At least I've spotted the cause of the fact that the graph bears no resemblance of today's situation... The value of L used is a fair bit lower than today's value. I'm going to have to find where that value comes from and how confident we are in it. Certainly the only value we've ever measured is much higher. -
shoyemore at 09:21 AM on 19 March 2011Maximum and minimum monthly records in global temperature databases
Anderson #53, Thanks for the reference. -
Rob Painting at 09:13 AM on 19 March 2011Maize harvest to shrink under Global Warming
Michael Sweet @ 38 - John D is simply acting the obstinate contrarian, but there is one point he raises which interests me; what improvement (yield %) would there be by comparing the most robust varieties against the trial average. The best of the best so to speak. He seems to believe that this would be significant, but that seems unlikely, given that years of selective breeding only provide incremental improvements. I'd be curious to know nevertheless. Arkadiusz Semczyszak - It has a very poor literature. Simple handwaving brutha. Some analysis?. As for Kim et al 2007, they don't look at yield, and there are so many differences between their experiments and the African field trials, it prevents a direct comparison. But I do note that even in conditions where they are well watered (mitigating heat stress) maize growth declines when temperatures exceed the low 30's. The point of the study of course was to see what effect, if any, CO2 fertilization had on maize. The answer was a resounding zilch. -
TimTheToolMan at 09:13 AM on 19 March 2011What would a CO2-free atmosphere look like?
@Bibliovermis "The CO2 came from unabated volcanic activity and tectonic forces over millions of years." But 66,000ppm (best case) is a lot of CO2. Thats what I mean by wondering whether the numbers add up. Is there enough time to do it? And where is it now? Do those numbers add up too? "I would agree that it makes little sense to look at things like Fig. 2 with a magnifying glass, but the general picture I have presented here is robust to different models and parameterizations" The thing is that people are now using those numbers in reasoning. Assuming the graph is from data output from those models, its pretty clear that the model didn't get it right and it didn't get it right in the area it was most likely to "get it right". What confidence does that give us about the areas where we have no knowledge? "while it is useful to know whether it takes 2000 or 4000 ppm of CO2 in the air to trigger glaciation under Neoproterozoic insolation, it plays little bearing on thinking through these problems on a forum like this." Its not 2000 or 4000 though is it? Its 66,000 or 660,000 and those numbers are much higher than I've seen our historic atmospheric concentrations of CO2 quoted to have been. Perhaps I've simply missed higher ones but the point is that this is a "sanity check" item. And because its so high (if it really is considered very high), then the question of where it came from and where it went to becomes necessary to consider. "are not hand-waving or other such “useless” exercises as he’d have people believe. " That hypothesis (that these results have some semblance of reality) has yet to be shown. Your answer is itself "handwaving". "Second, there is a rather weak vertical temperature gradient in the summer hemisphere of a snowball..." ...fundamentally assumes snowball earth is a a hard snowball which is quite an assumption. -
RickG at 08:51 AM on 19 March 20112nd law of thermodynamics contradicts greenhouse theory
damorbel, The diagram, or schematic as Trenberth calls it, is from one of his many PowerPoint presentations. In other words the schematic is meant to be presented with discussion in context with his presentation. The schematic as many of us have pointed out to you is about incoming solar energy and how it is distributed throughout the climate system taking different forms of energy. In describing this, not only by Trenberth, but all scientists, use the proper units of measure which is watts per square meter, not temperature. But since no one seems to be able to convince you of that, watch Trenberth describe that very schematic himself in this video. -
les at 08:40 AM on 19 March 20112nd law of thermodynamics contradicts greenhouse theory
661 Rysn good try at a twist. I'm afraid that it's transparent to all here that you really are not "doing physics" in your argumentation. At thus stage, really, we're just playing with you. Dont take your arguments so seriously - no one else is. -
Albatross at 08:32 AM on 19 March 2011How Suffolk County Community College students contributed to the Guide to Skepticism
Great news-- wonderful that the students were involved. John a question and a suggestion. How many people have downloaded the booklet to date? The suggestion, maybe one could include text bubbles in that graphic showing the three lonely contrarians (i.e, room full of climate scientists). Maybe something like: Spencer--"Dick where are you, I'm lost?" Lindzen-- "Over here Roy, waay over here. Don't worry, I'm lost too" Spencer-- "OK, but have you seen John (Christy)?" Dick-- "Umm, not sure, saw him a few hours ago looking very lost." Three lonely and wayward "skeptics" lost in a sea of science, facts and reason :)Response: The booklet has been downloaded around 128,000 times since December (that's not counting other websites hosting the booklet or translations).
I'll take the speech bubble idea under advisement :-) -
2nd law of thermodynamics contradicts greenhouse theory
L.J. Ryan - Since the Trenberth numbers are an energy budget, they should add up and cancel out for an unforced climate. If, however, you carefully add up the Trenberth numbers without rounding you get an imbalance of about 0.9 W/m^2 less leaving than arriving. That's the forcing. -
L.J. Ryan at 07:38 AM on 19 March 20112nd law of thermodynamics contradicts greenhouse theory
scaddenp666 Oh...Tom and Trenberth count the photon/flux twice. So the vector sums are zero, no atmospheric forcing...no AGW. You have confirmed my position. -
pbjamm at 07:19 AM on 19 March 20112nd law of thermodynamics contradicts greenhouse theory
L.J Ryan@559 No you would not have a laser, the beam would not be directional since photons would reach the aperture at a variety of angles and travel out that way too. From a photon=particle bouncing around standpoint I think the brightness of that beam would diminish over time as the number of photons hitting the aperture/sec would diminish along with the number in the box. "Light Decay" in the context of the discussion is light losing energy to the imperfect mirrors. As for Tom Curtis' original diagram @615 I think the missing element in most of this discussion is time. Over time A=C but not for every photon interaction. We need to be clear if we are talking about an instantaneous measurement or the totals over time. Same goes for the Trenberth Diagram. note: I am not a physicist nor mathematician. I reserve the right to be wrong. -
Riccardo at 07:09 AM on 19 March 20112nd law of thermodynamics contradicts greenhouse theory
damorbel given that you know how to calculate temperature from the energy flux, why are you asking Trenberth to report it in a summary graph? You really look polemical here, it adds really nothing to the discussion or to the undersdtanding of the energy budget. -
Chris Colose at 07:02 AM on 19 March 2011What would a CO2-free atmosphere look like?
I would agree that it makes little sense to look at things like Fig. 2 with a magnifying glass, but the general picture I have presented here is robust to different models and parameterizations, and also within the geologic record (particularly cap carbonates as a key indicator that the Neoproterozoic glaciations and deglaciations involve a jump between extremely different states). Different cloud parameterizations and feedbacks, simulation of circulation, etc may yield different results, and while it is useful to know whether it takes 2000 or 4000 ppm of CO2 in the air to trigger glaciation under Neoproterozoic insolation, it plays little bearing on thinking through these problems on a forum like this. This is how science advances in general, by building a useful scaffold upon which more technical details can be later hung. I feel like this is self-evident to most people here, and TTTM is just trying to argue; certainly, the results of something like Fig. 2 emerge in simple zero-dimensional energy balance models as well as in full flown GCM’s, and are not hand-waving or other such “useless” exercises as he’d have people believe. There is no fascination with attacking Lindzen either, he was just wrong, and admitting that rather than trying to defend it through “arguments from complexity” would be one more step toward a good discussion. Concerning the rather weak climate sensitivity in a snowball Earth, there are several published mechanisms for why this is the case. The first is the very weak water vapor feedback, which is relatively unimportant in regimes where the tropics are frozen. Without the help from water vapor, CO2 has limited power to warm up a Snowball Earth to the point of deglaciation. This is much less true for condensed water, which is much more efficient of an infrared absorber than water vapor. Second, there is a rather weak vertical temperature gradient in the summer hemisphere of a snowball, and even weaker in the winter hemisphere in which convection is suppressed (much like over Antarctica in the winter). The greenhouse effect can only operate insofar as you have colder air aloft to work with, so a weak lapse rate inhibits the ability for CO2 to do much. In regimes where you could condense CO2 as a cloud, you could generate a scattering greenhouse effect (rather than the traditional absorption and re-radiation we are used to) that works largely independent of the lapse rate (though this also serves as a limit to CO2 accumulation). This could play a role in Polar Regions in the winter time during the Neoproterozoic at high CO2 levels, early earth snowballs, or on early Mars for example.Moderator Response: [DB] Fixed Fig 2 reference per request. -
damorbel at 06:48 AM on 19 March 20112nd law of thermodynamics contradicts greenhouse theory
Re 650 RickG :- "For what Trenberth is demonstrating temperature is neither necessary or relevant in that diagram. I have no problem understanding the diagram myself." It is difficult to believe that a diagram showing emission of thermal radiation (W/^m2) can be considered useful when no indication is given of the temperature of the emitting body; why else would the Stefan-Boltzmann equation (E= rhoT^4) be so widely deployed in thermal physics?Moderator Response: [Muoncounter] you raised this identical 'objection' in November, 600 comments up this very thread. The same replies you received then still apply now. Insistence on mere repetition demonstrates that your argument ran its course. -
Kiwiiano at 06:46 AM on 19 March 2011The Scientific Guide to Global Warming Skepticism
I was looking to commit the booklet to paper, but it needs to be done in colour to preserve the graphics, but much of the text will look terrible on paper. Any chance of a printable version?Moderator Response: [DB] Try here. -
scaddenp at 06:36 AM on 19 March 20112nd law of thermodynamics contradicts greenhouse theory
L.J. Ryan - back to the original light box. We agree that the set up does NOT violate 1st law? No where in the system is energy being created. The thing that seems counter-intuitive apparently is that energy-fluxes appears to double. Whoa! energy creation! No. This illustrates that care has be taken in inferring system energy from energy flux, because in this case, with reflection, the same energy gets counted twice. This is no violation of 1st law going on in Tom's example - nor in Trenberth's diagram for same reason. Just an illustration about care in use of energy flux. -
citizenschallenge at 06:34 AM on 19 March 2011Christy's Unconvincing Congressional Testimony
Wasn't Christy's testimony Under Oath? Isn't there any recourse for officially disputing the factuality of his testimony? -
2nd law of thermodynamics contradicts greenhouse theory
Fred Staples - That's a fairly reasonable (if wordy) description of Entropy. You could have just linked to an existing definition and saved much typing. I think I see where you're going - to an argument that the high levels of IR at the surface somehow violate entropy considerations. You might find my comment here relevant in that regard. We aren't dealing with a closed system, but rather a very open one, where the important issues are rate of energy flow, energy differentials, and internal temperatures and energy levels required to maintain a dynamic equilibrium. Not moving a fixed amount of energy around a closed system. Entropy is increasing as sunlight radiates out into the 3K void of space. Local conditions regarding the conversion of that visible light into thermal IR provide a pinch-point, much like the dam in my analogy, one that includes a local collection of energy in order to have an energy differential sufficient to radiate the IR to space. -
Fred Staples at 05:42 AM on 19 March 20112nd law of thermodynamics contradicts greenhouse theory
The energy quality I described in 498 is obviously related to the inverse of entropy, but people struggle with the latter concept. It is easier to see that quality is related to useful energy – that is, energy that can actually do something, such as producing useful work or raising temperature. In any spontaneous transaction involving energy transfer, quality will diminish. What this means is that the energy cannot go backwards, and some of the useful energy will be lost. (I said I would not mention the second law, but that is what it is really about). Incidentally, 499, real life energy losses through friction, etc, make the situation worse. Energy quantity as well as quality is lost to the system Here is another elementary example. An insulated vessel contains gas at a high temperature, and is separated from a vacuum, within the vessel, by a membrane. If the membrane is punctured, the gas flows into the vacuum, and its pressure drops. No work is done, no heat is lost, so the temperature remains the same. The first law says that energy has been conserved. But the gas is obviously able to do less work, starting from the lower pressure. It is also obvious that (Maxwell's demon apart) the gas cannot go back. What has happened is that the quality of the energy has fallen. It turns out (as the pundits say) that it is this elusive characteristic of quality (strictly entropy) that drives all spontaneous transactions – literally everything from chemistry, biology, energy transfer and (fancifully) the tidiness of your desk. It is the quality of energy, not the quantity, that makes something happen. Here are two well known examples. Suppose that a single gas flame operates at a temperature below the melting point of a steel plate. The steel will not melt because the quality of the flame energy is too low. Now apply ten more similar flames. Still the steel will not melt. Another example is Einstein’s experiment to eject electrons (I forget from what) with a beam of incident radiation. Below a certain frequency (energy quality) nothing happened, no matter what the intensity (energy quantity). Above that frequency, electrons were ejected, and quantum mechanics was born. Sadly, however, my definition of quality (available energy) is too simplistic. It is the relative quality that matters. Switching the argument to a power generator, a source with a high temperature can generate work by transferring energy to a sink at a lower temperature. The available energy is high. If the sink is at the same temperature as the source, nothing will happen. There is no available energy. Likewise, if the sink energy can be connected to a second sink with a lower temperature, space heating is possible. Otherwise the waste energy will be ejected to the atmosphere through cooling towers. So, if I have persuaded anyone that the crucial elements of energy transfer are the qualities of the energies concerned, and that energy can’t go backwards without the performance of extraneous work, we can move on to an even more elusive concept. Heat. -
2nd law of thermodynamics contradicts greenhouse theory
LJ> In that specific comment, Tom clearly indicated he was talking about a "real-world" box that would not be perfectly reflective. In that case "decay" would be the light escaping the box. I have not contradicted a single thing Tom said, you just aren't reading what's being written. -
L.J. Ryan at 05:38 AM on 19 March 20112nd law of thermodynamics contradicts greenhouse theory
e 660 I asked a question...What is light decay? You are not contradicting Tom,suit yourself. -
Bibliovermis at 05:33 AM on 19 March 2011What would a CO2-free atmosphere look like?
The CO2 came from unabated volcanic activity and tectonic forces over millions of years. Snowball Earth by Paul F. Hoffman and Daniel P. Schrag, Scientific American, January 2000 -
L.J. Ryan at 05:30 AM on 19 March 20112nd law of thermodynamics contradicts greenhouse theory
les655 "Ryan, well, no actually. Not for that weird selective filter thing. Still, given the arbitrary was bits of physics are being thrown around this thread; have it your way, what the hell! " I agree sloppy physics, lot fundamental violations. The weird filtering was Tom's not mine. Are you familiar with Kirchhoff's black body cavity theorisation/experiment? -
2nd law of thermodynamics contradicts greenhouse theory
LJ> Everything you said in post 658 is false. I will not detail the problems because they are all simple reading comprehension errors. If you're not going to make any effort to read and comprehend the point that is being made then you are not here for intelligent discussion; there's no point in talking to you. -
L.J. Ryan at 05:20 AM on 19 March 20112nd law of thermodynamics contradicts greenhouse theory
e656 pbjamm657 Make the aperture diameter 2x photon diameter, and shazam you have a flashlight powered photon laser. -
michael sweet at 05:17 AM on 19 March 2011Those who contribute the least greenhouse gases will be most impacted by climate change
Gilles: You said "use of FF increases the wealth" of countries. I have provided a specific counter example and all you can say is it is because France uses nuclear? Tell me something I don't already know. You make my point: other energy sources can be used to support a modern economy. Your claim that FF use is proportional to success in a modern economy is proved incorrect. When 2010 numbers come out it will show that Spain got 16% of their electricity from wind and they continue to rapidly install turbines. No problem with increasing coal and oil prices there! Please provide references to your extraordinary claims. -
Utahn at 05:12 AM on 19 March 2011Water vapor is the most powerful greenhouse gas
Neglected to mention that in the Boucher article, they note that there is some significant counteracting cooling as well that occurs due to the irrigation/evaporation cooling the area irrigated (not to mention land albedo changes from vegetation etc...) -
L.J. Ryan at 05:12 AM on 19 March 20112nd law of thermodynamics contradicts greenhouse theory
e654 "So his assumption with that statement was that in reality you cannot have perfectly reflecting walls. Now stop trying to nitpick and give his example some real thought." The perfectly reflective wall was Tom constraint not mine. Violating the 1st law in order to illustrate radiative forcing is not nitpicking, rather it's very fundamental. To say emissivity >0 leads to "light decay" is a convenient concept...does the photon slow down until comes to rest at the bottom of the box? What is light decay? Tom said: "The answer has to be in terms of photon numbers, not energy because the wavelength of the photons has not been specified. If we specify that all photons have the same wavelength, then the multipliers for photons in the answers above can be used for energy." you say: "To convert wavelength into energy per photon, use the equation h*c/wavelength. You can type this directly into google like so "h * c / 11364 nm". Once you have that number is just a matter of multiplying it by the number of photons, try it yourself." You seem to be at odds with Tom. Your suppositions concludes, regardless of wavelength the accumulated ENERGY within the box is twice the input...as detailed by @646 -
Utahn at 04:59 AM on 19 March 2011Water vapor is the most powerful greenhouse gas
In different water vapor threads I have seen comments that continually added water vapor(i.e. fossil fuel combustion/irrigation) might act as an anthropogenic forcing of climate change. This makes sense to me (continual addition of vapor overcoming the short residence time) so I looked around and found a couple of places this was addressed: one is a grad student at UCBoulder's website and I'm not sure how good his numbers are but the explanation and detail is very easy to understand, and he concludes that water vapor from combustion is a trivial addition. The other is an article (Boucher 2004), again I'm not qualified to say how "good" the article is, but they estimate that irrigation *does* add to global radiative forcing by up 0.03 to 0.1 W/m2, again a trivial amount compared to C02 or total water vapor forcing. If the mods/author thinks these links look "up to snuff", they might be a useful addition to add to the article for people looking at this aspect of the argument and wondering about "directly anthropogenic" water vapor. -
pbjamm at 04:48 AM on 19 March 20112nd law of thermodynamics contradicts greenhouse theory
L.J Ryan@651 "So the accumulated "boxed" light would radiate 1W for a 100 hrs, once the second aperture is opened?" Wouldn't that depend on the size of the aperture? On the photon level wouldn't the "flow rate" out of the aperture change as less light remained in the box? Fewer photons would be available to hit the target/sec. I imagine it would be a bright and rapidly fading light once the hole was opened. Since this is all imaginary... -
2nd law of thermodynamics contradicts greenhouse theory
LJ@651 >So the accumulated "boxed" light would radiate 1W for a 100 hrs, once the second aperture is opened? The wattage of the aperture would be entirely determined by the the size of the hole, the size of the box, and the amount of energy in the box. As the energy escapes from the box the wattage of the aperture decreases. It has no relationship to the original wattage of the flashlight. That value is determined by the flashlight's ability to convert chemical energy into radiant energy. In this example all the energy is already radiant. The box doesn't "remember" the wattage of the original light source. -
Utahn at 04:35 AM on 19 March 2011Those who contribute the least greenhouse gases will be most impacted by climate change
Gilles: "Where is the problem ?" The problem is not that there are correlations with wealth and fossil fuel use, just that *you state that fossil fuels increase wealth* and don't support your statements of causation with any facts. As I asked before, do you believe correlation is causation? -
les at 04:33 AM on 19 March 20112nd law of thermodynamics contradicts greenhouse theory
653 damorbel: again, we are in complete agreement in not completely understanding the bits where I quote you. Still, to do what you require follow the advice of others here and read the full papers rather then looking at the pretty pictures. 652 Ryan, well, no actually. Not for that weird selective filter thing. Still, given the arbitrary was bits of physics are being thrown around this thread; have it your way, what the hell! -
2nd law of thermodynamics contradicts greenhouse theory
LJ@651 >Sounds like a violation of the 1st law...remember perfectly reflective walls. Sounds as if you don't believe your own answer. The full context of that comment was: "... in practise you would not have perfectly reflecting walls," So his assumption with that statement was that in reality you cannot have perfectly reflecting walls. Now stop trying to nitpick and give his example some real thought. >ok lets assign three wavelengths and redo @646 As Tom pointed out this would just be a multiplier i.e. energy per photon X number of photons. To convert wavelength into energy per photon, use the equation h*c/wavelength. You can type this directly into google like so "h * c / 11364 nm". Once you have that number is just a matter of multiplying it by the number of photons, try it yourself. Re: question 1a) The aperture he is referring to is the open hole where the lid used to be. There is no aperture in Tom's original example. Re: question 2a) The lid still holds the same properties it did in the original example, i.e. it transmits 50% and reflects 50%. -
damorbel at 04:17 AM on 19 March 20112nd law of thermodynamics contradicts greenhouse theory
Re #649 les, you wrote:- "damorbel 648 - fine. We agree on so much including, it would seem, that the diagram is not "completely deficient in temperature information". " I think there is a definite problem there. I'm afraid I do not understand just what is it that makes you say:- " the diagram is not "completely deficient in temperature information". ? and:- "It clearly does "present ... useful information for any discussion on climate change " I'm not sure what you mean here. I am of course thinking of 'useful information' in the sense of scientific information, suitable for putting in reports called 'the Scientific Basis', the name of the sections of IPCC reports using this diagram. Trenberth's diagrams are among the few (perhaps only) in IPCC reports showing directional energy effects from greenhouse gases, I cite them because, without temperature, any figures showing energy emissions from the atmosphere, the Earth's surface or anything else have no scientific basis. -
L.J. Ryan at 03:58 AM on 19 March 20112nd law of thermodynamics contradicts greenhouse theory
les 638 No not Maxwells Demon, but rather Kirchhoff's black body theorisation.
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