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archiesteel at 06:23 AM on 15 December 2010Renewable Baseload Energy
As far as cost is concerned, I wonder if they include the fact that mass production of solar and wind microgenerators would continue to lower costs overtime, making it more competitive. Personally, I like the idea of renewables as part of third world development strategy. Africa has enormous solar potential (mostly in the form of concentrated solar), and the technology is easier to master for what sadly remain regions with limited technical/technological education. In this context microgeneration plays a part, especially for tribal population who do not use much (but would like some) electrical power. As I said, there is no single solution. I wish we would at least agree on that, as I've already spent too much time arguing about this. After all, that time used a significant amount of that precious electricity (I don't type with the monitor off, for example). So in the spirit of conservation I'll say no more about this, and will leave you with the last word. I know my case is strong enough to challenge yours and keep the debate open for others, and that's fine with me. -
Ned at 06:17 AM on 15 December 2010The 2nd law of thermodynamics and the greenhouse effect
With increase in GHGs: 1. Altitude of emission increases 2. Temperature at new altitude has to increase to maintain incoming/outgoing radiation balance 3. With constant lapse rate, surface must warm. You would learn a lot if you'd spend more time reading Science of Doom. -
damorbel at 06:05 AM on 15 December 2010The 2nd law of thermodynamics and the greenhouse effect
Re #224 DSL You asked for a y/n answer to this question :- "do you think the temperature of the 1) Earth's surface and/or 2) lowest ten meters of the troposphere would be different in the absence of atmospheric CO2?" No the temperature would not be different. Your response was to my statement:- "3/What is in your or anyone else's writing, that explains just how the presence of GHGs change a planets surface temperature from that in the absence of GHGs?" The temperature profile (dT/dz) of the troposphere is fixed by the lapse rate which is a function of the specific heat of the atmospheric gases. If the GHE was serious i.e. produces a 30K rise in surface temp. there is not a lot of room for it in the lapse rate calculations. NB the lapse rate would be no different without GHGs. -
The 2nd law of thermodynamics and the greenhouse effect
damorbel - Did you see my post here? It was addressed to you - you've replied (in one fashion or another) to several other posts since that one. -
RSVP at 05:30 AM on 15 December 2010Ice data made cooler
michael sweet #51 "...three factors of ten" As I know nothing, is it OK to ask what three factors of ten is? At any rate, it looks like this subject has been shut down, so you're in luck and dont have to answer that question, even though it has nothing to do with CO2 or polar caps. My last peep (if permitted) would be that as CO2 out gasses I assume there will always be less and less in the ocean, so this effect would curtail at some point, would it not, or should we assume there will always be plenty more CO2?Moderator Response: [muoncounter] No, the subject isn't 'shut down'; all you need to do is move to the more appropriate thread. You can refer back to comments here by right-clicking the red date and time, copying the link location and inserting that as a link in your subsequent comment. -
damorbel at 05:22 AM on 15 December 2010The 2nd law of thermodynamics and the greenhouse effect
Re #223 Composer99 You wrote:- "You agree with four of the questions archiesteel puts to you; where agreement would seem to indicate agreement with some sort of greenhouse effect." I ceratinly said I didn't agree with archiesteel's first question:- "...they emit IR energy, as described by black body theory... " The idea that a body that reflects 30% or more of incident light can emit 'as described by black body theory' is completely absurd. The measuring of emissivity (e) is difficult to do directly; it is more easily done by measuring the reflectivity (r) and calculating emissivity as e = 1 - r Perhaps you do not realise that, by using the correct value for emissivity i.e. not making the false assumption of the Earth emittting 'like a black body', then the mean temperatute of the planet is 279K, not the 255K claimed in the opening argument for a GHE. You mention other contributors, I'll answer them on their own terms. Thanks for your interest. -
Stephen Baines at 05:12 AM on 15 December 2010Ice data made cooler
Oops...sorry about being off topic! The curse of following links to posts from recent comments section! -
Stephen Baines at 05:10 AM on 15 December 2010Ice data made cooler
Tom @52... you mispoke when you wrote " the majority of CO2 in sea water is not dissolved.." Obviously that inorganic carbon in carbonate and bicarbonate ions is dissolved. That could lead to some confusion as there are large pools of undissolved carbonate in the ocean that may also play a rol, especially in light of ocean acidification. To be clear to RSVP and others...dissolved CO2 (and carbonic acid -- the two species cannot be distinquished readily) accounts for only a small part of the total dissolved inorganic carbon pool in the ocean. This is because the current pH of the ocean (as determined by temp and cation concentrations) favors formation of bicarbonate and carbonate from CO2. But as Tom points out all of these species are in dynamic equilibrium with each other, so basically, the whole dissolved inorganic carbon pool has to be considered exchangeable with the atmosphere. Any shift in solubility of CO2 (ie., via temp) tends to result in net loss of dissolved CO2 to the atmosphere which causes dissociation of carbonate and bicarbonate. You can calculate the release that would result from warming (or acidification) using well established equations. However, because of the effects of cations and pH (which changes with dissociation of carbonate/bicarbonate) on the equilibrium, predicting the exact amount exchanged takes solving a set of equations to determine the new equilibrium points. Back of the envelope calculations won't cut it. -
Philippe Chantreau at 04:56 AM on 15 December 2010The 2nd law of thermodynamics and the greenhouse effect
Incidentally, the reality of the "greenhouse" effect can be verified with a relatively simple experimental set-up. The ESPERE site describes it quite well: http://www.espere.net/Unitedkingdom/water/uk_watexpgreenhouse.htm It could be improved by taking into consideration the water vapor present in the air vessel, but the basic idea is there. -
Philippe Chantreau at 04:44 AM on 15 December 2010The 2nd law of thermodynamics and the greenhouse effect
"But if you do not specify the amount of material the temperature, for a given amount of energy, is completely unspecified." What a strange way to look at things. As if it was possible to measure the temperature of something but not know what it is at all. "I measured the temperature of that object but I have no idea of its size, what it's made of and all that" How could you then measure its temperature? I mean, what would you measure the temperature of? Does one not define an object before measuring its temperature? Of course, the exact mass will never be known to the last atom but who cares? It's enough to know it to the extent necessary to have a decent idea of the heat content. Which is the all point of measuring temperature; you have not demonstrated otherwise by this weird argument, certainly not "remotely" otherwise. You are wrong on the stratosphere. It is well known that GHGs cool down the stratosphere. Line by line radiative transfer models show how much, with the altitudinal distribution. That has been verified by observation too (Iacono and Clough 1995 and later papers). In post #220 you agree that IR radiation is re-radiated to the surface. How can this happen without the surface temperature to increase if thermodynamic compliance is respected? It is a good thing that you agree on this point, however, because it has been measured too; these measurements, once again, agree quite well with MODTRAN and LBLRTM. That was confirmed by Marty et al (2003), solidifying even more the Iacono and Clough results and MODTRAN. Heck, even Judith Curry has papers showing agreement between downward IR flux at the surface and results from a wide variety of models. "In an 'Earth' atmosphere, but of pure CO2, can you tell me, on a scale of 1 to 100, what % of photons emitted at a height of 5km will reach the surface without being reabsorbed?" I would not expect any individual here to be able to answer that question. That's what MODTRAN or other models do and they take significant computing power. But their results are very, very close to the observed reality. It is probably not the best question to ask because there are photons emitted at all altitudes anyway. A lot of words, a lot of weird ideas, nothing convincing. -
Tom Curtis at 03:40 AM on 15 December 2010Ice data made cooler
RSVP @48, one factor you are not taking into account is that the majority of CO2 in sea water is not dissolved, but rather as carbonate (6%) or bicarbonate (93%). Because these are in equilibrium with disolved CO2, a given reduction in the partial pressure of CO2 due to a warming ocean will result in the release of approximately 100 times more CO2 than your formula (if correctly calculated) would predict. Data on the ratio of dissolved CO2 to the various carbonatets can be found at the bottom of the page you mention. Of course, because so much CO2 is released, the partial pressure of CO2 in the atmosphere will rapidly increase, establishing a new equilibrium between atmosphere and ocean. Consequently simply multiplying your values by 100 will not determine a correct value for increase in atmospheric CO2. For what it is worth, Indermuhle et al, 1999 (Warning, PDF) quote an earlier paper to the effect that for each 1 degree C increase in Sea Surface Temperature, there is a 4.2% reduction in the partial pressure of CO2 in surface waters, with a corresponding increase in atmospheric CO2.Moderator Response: [muoncounter] This thread is about ice data (and how cool it can be). Take the ocean carbonate, bicarbonate, dissolved gas discussions et al. here. John, consider consolidating argument #89 'CO2 is coming from the ocean' with 'Ocean acidification'. -
archiesteel at 03:21 AM on 15 December 2010Renewable Baseload Energy
Also, microgeneration does have a significant advantage over large-scale power plants: since the energy is generated at the point where it is used, there is no loss of power during transmission. Up to 8% of electricity is wasted due to transmission over long distances. Another advantage is that you can still have power even when power grid fails. Decentralization also means less stress on the grid, and reduces maintenance costs. Is microgeneration the answer? No, it isn't, not by itself. As I said, a varied ecosystem of energy sources is the best option, even though it does mean less money for Westinghouse... -
michael sweet at 03:17 AM on 15 December 2010Ice data made cooler
RSVP: You have not considered pH, salinity or mixing, among many other important factors. pH alone could give as much as three factors of ten. You cannot do this calculation in the manner you propose. My post 22 and Alec's post 47 give clear qualitative results that explain your question. According to your new reference, CO2 is 5 times more concentrated than O2 and N2 combined (90 ppm vs 19.5, you are apparently unable to read your own table). Approximately 5 times as much CO2 will be released as N2 and O2 combined. The change in O2 and N2 is too small to measure. Post 47 and 22 explain this completely. It is very frustrating to provide a clear, simple answer to your question (at post 22 and 47) and have you deny that your question has been explained. This happens to you repeatedly, so I am not the cause. "The longer you go on the clearer it is that you do not know what you are talking about. You are legendary for the "waste heat" After 10 posts you are not even within an order of magnitude in your calculation. You do not know enough chemistry to correct your calculation. You have provided data that proves your argument is completely wrong. Do you imagine you will ever be able to convince me that you have done this calculation correctly? Do you realize that scientists are professionals who do this for a living? Your back of the envelope calculations (filled with obvious errors) mean nothing compared to a professionals careful, peer reviewed work. For someone who has a complete lack of basic chemistry and physics knowledge, you make a lot of posts suggesting scientists need to do better work. Get you act together!!! -
archiesteel at 03:10 AM on 15 December 2010Renewable Baseload Energy
@quokka: well, I guess we'll just have to agree to disagree. I do believe the cost of nuclear is higher than the studies suggest, and I do believe you are too quick to dismiss the effect (and popularity) of microgeneration. Simply put, the more people reduce their energy consumption through microgeneration, the less power will be required of the grid at large. Furthermore, as long as you continue trumpeting nuclear as the only solution, you will turn people off of it. In other words, your advocacy is actually having a negative effect. You are also ignoring the political aspect, i.e. the strength of the NIMBY effect, and the geopolitical puzzle linked to nuclear energy (security and strategic issues, etc.). The fact that you can't admit a single weakness of nuclear energy is highly suspicious, in my view, but I'll refrain from saying what I really think so that my comment doesn't get deleted. -
archiesteel at 03:03 AM on 15 December 2010The 2nd law of thermodynamics and the greenhouse effect
@damorbel: "No. Just as objects like planets do not absorb 100% of the incident radiation from the Sun because a certain % (called the albedo) is reflected, neither is 100% radiated." I never claimed 100% of the Energy was radiated. Stop putting words in other people's mouth in order to peddle your incorrect interpretation of physics, please. "What you should realise is that the % 'trapped' by a radiating planet is exactly the same as the % of the incoming radiation reflected as albedo." Wrong. The higher the albedo, the less energy is transferred to the surface, as the visible light is mostly reflected back into space. Are you really that misinformed, or are you indulging in disinformation? "Do you also accept my argument that the scattering/reflection processes that cause the albedo is completely independent of the direction of arrival of the photons that are scattered?" This is rather irrelevant, isn't it? Anyway, I disagree. Scattering and reflection are not equivalent, as reflection does indeed have a directional component (think of an object with 100% albedo, i.e. a mirror). "In an 'Earth' atmosphere, but of pure CO2, can you tell me, on a scale of 1 to 100, what % of photons emitted at a height of 5km will reach the surface without being reabsorbed?" No, I can't, but the exact figure is irrelevant. As I said, some IR energy will escape to space, some will warm the surface, and others will be reabsorbed and re-emitted. The time it takes for the energy to eventually reach space or the surface is inconsequential, just like the time it takes for a photon to go from the center of the sun to its surface and beyond is inconsequential to the fact it will eventually escape. Either you have a real problem with logic, or you are using this forum as a propaganda pulpit. Either way, please stop. "What is in your or anyone else's writing, that explains just how the presence of GHGs change a planets surface temperature from that in the absence of GHGs?" I just explained it to you, and you agreed on pretty much all points, except on the one about Albedo, but that's because you don't really understand the difference between reflectivity and absorbption/emmission. Again, you've been shown to be wrong on this many, many times. The fact you continue to make false statments really make me believe you're interested in pushing an agenda, not learning the truth. So, you agreed with my points, and I showed how yours are incorrect. I guess this means you have lost the argument. Sorry. -
muoncounter at 03:02 AM on 15 December 2010Ocean acidification isn't serious
Follow up from here. Excellent link posted by RSVP. Ocean CO2 concentrations on the increase, as of 2006Odd, the largest changes in the Atlantic are in the northern hemisphere, the Indian is worse in the south, but the Pacific seems even.
Moderator Response: I take back the 'excellent link' opinion. The website has an extensive page in denial of AGW. -
Albatross at 02:56 AM on 15 December 2010An Even Cloudier Outlook for Low Climate Sensitivity
HR @75, "Do those few data points have a larger impact on the slope of the graph than the pile of data points in the middle?" That is a possibility. But is hard to say without having access to the data. Dr. Dessler realizes that there is not much data here-- even thought the ECMWF-interim data go back to 1989, CERES was launched on board NASA's Terra satellite in late 1999 (apparently a CERES instrument was launched on board TRMM in late 1997, but I'm not sure why they did not use those data, maybe there were issues with the early instrument?). Given the relatively limited data (120 data pairs), Dessler has answered your question when he says: "Obviously, the correlation between DRcloud and DTs is weak (r^2 = 2%), meaning that factors other than Ts are important in regulating DRcloud. An example is the Madden-Julian Oscillation (7), which has a strong impact on DRcloud but no effect on DTs. This does not mean that DTs exerts no control on DRcloud, but rather that the influence is hard to quantify because of the influence of other factors. As a result, it may require several more decades of data to significantly reduce the uncertainty in the inferred relationship." My read of this paper is that it is a sincere and honest effort to address an important, but vexing, problem in climate science. I have to yet come across the "ideal" data set in my field, you do the best with what you have. Dessler has developed and tested a methodology which can be applied in the future as more data becomes available. That, contrary to what Dr. Spencer might believe, is a step forward for science-- something that Dessler seems genuinely concerned and passionate about. The novelty and strength of this paper lies in the fact that, unlike LC09, Dessler is looking at global data and that his approach implicitly includes clouds of all types (i.e., other studies have focused on just low clouds, for example). Finally, this paper, demonstrates that the models are (in the short-term at least) actually doing a decent job in simulating the cloud feedback the short-term, and is also further evidence that (while not discounting the possibility of a very weak feedback) that a cloud feedback is in all likelihood positive, with an approximate 95% confidence interval (equivalent to about 2 sigma) of the mean of +0.54 W/m^2/K between -0.2 and 1.3 W/m^2/K. I would also suggest reading the very last paragraph of his paper starting with "For the problem of...". -
muoncounter at 02:54 AM on 15 December 2010Ice data made cooler
#48: Excellent link, RSVP. But well off-topic for this thread, which is about ice data. Look down the page for the two graphics showing how much both the oceanic concentration of CO2 and ocean water pH have changed, according to measured values. Followup discussion on that subject should go here. -
Albatross at 02:33 AM on 15 December 2010An Even Cloudier Outlook for Low Climate Sensitivity
Eric @70, "....(the model Dessler used to get the top chart in the post) it seems like the AGCM has no mechanism to use convection and latent heat transfer to estimate the lapse rate" The top panel of the chart you refer to is based on ECMWF-interim (reanalysis) data. Are you referring to the ECHAM AOGCM? If so, why a link then to the NASA GEOS-5 assimilation model? I'm not not seeing what your thoughts have to do with Dessler's paper. -
Paul D at 02:30 AM on 15 December 2010A new resource - high rez climate graphics
This is a good move IMO. Florence Nightingale changed British hospitals as a result of one simple diagram (and a lot of campaigning). -
Alec Cowan at 01:46 AM on 15 December 2010Ice data made cooler
@ RSVP "Not sure if this is due to bacteria or what, ..." Your ratios are off due to bacteria !? Please, elaborate. -
RSVP at 01:25 AM on 15 December 2010Ice data made cooler
michael sweet #46 "The longer you go on the clearer it is that you do not know what you are talking about. You are legendary for the "waste heat" This sounds like an ad hominem to me. (i.e. since I didnt consider atomic mass, moles etc., to do my calculation, everything I could have possibly said about waste heat is completely untrue.) ... and not being able to substantiate your argument because the blog medium is a cop out. I could understand if you were complaining about not getting paid for it. Here we go again... http://www.engineeringtoolbox.com/gases-solubility-water-d_1148.html @20 degrees solubility N2 in water = 0.0158 g/ kl solubility O2 in water = 0.045 g/ kl solubility CO2 in water= 1.5 g/ kl considering... N2 79%, atomic mass 28 O2 20%, atmoci mass 32 CO2 .04%, atomic mass 44 this yields... @20 degrees solubility N2 in water = 5.64e-4 mol/ kl solubility O2 in water = 0.0014 mol/ kl solubility CO2 in water= 0.0341 mol/ kl Normalizing this for CO2, you get @20 degrees solubility N2 in water = 0.017 solubility O2 in water = 0.041 solubility CO2 in water= 1 again, taking into account the ratio of atm. comp... N2 roughly 80% O2 20% CO2 .04 % normalizing this to CO2 you get N2 2000 O2 500 CO2 1 taking these results, you would expect to find the following ratio of gases dissolved in seawater at 20 N2 2000 x 0.017 = 34 O2 500 x 0.041 = 20 CO2 1 x 1 = 1 However, I just checked this link... http://www.seafriends.org.nz/oceano/seawater.htm which contains a beautiful table in about the middle of the webpage that just happens to contain information on this. As you can see, according to the data, my ratios are off by a factor of ten. Not sure if this is due to bacteria or what, but even still, you have more O2 and N2 than CO2 in the water. -
funglestrumpet at 01:14 AM on 15 December 2010A new resource - high rez climate graphics
Thanks for all your hard work! Now we need to take action. To continue arguing about whether Global Warming is human induced is a distraction, and one I am sure the fossil fuel industry loves, because it serves to delay action and thus delay their reduction in profits. You recently recommended a book showing that the fossil fuel industry was using the same people to lead their campaign against taking action as was used to 'disprove' that tabacco smoking causes lung cancer, and that HFCs do not affect the ozone layer. These people are devoid of scruples. We know the science concerning CO2 and the greenhouse effect. It matters not whether the current level of CO2 was human in origin or caused by the ravenous bug blatter beast of Traal. What really matters is that we from now on do whatever we can to reduce CO2 emissions. We could shoot the aforementioned beast, if we can find it, but even if we do, we had better cut down on our production. To not take action is akin to refusing to steer round an iceberg on the basis that we humans did not make it. -
DSL at 01:13 AM on 15 December 2010The 2nd law of thermodynamics and the greenhouse effect
Damorbel: "3/What is in your or anyone else's writing, that explains just how the presence of GHGs change a planets surface temperature from that in the absence of GHGs?" You've been asked this before, I believe: do you think the temperature of the 1) Earth's surface and/or 2) lowest ten meters of the troposphere would be different in the absence of atmospheric CO2? Yes or No? -
Alec Cowan at 01:09 AM on 15 December 2010Ice data made cooler
@ RSVP #45 Departing from 250ppmv CO2 and 209000ppmv O2 I arrive to 400ppmv CO2 and 209042ppmv O2 by making some reasonable assumptions (the conclusion won't change for making a more precise calculation). You have been said once and again your calculations are wrong -nobody would point each value and provide the valid one-. Any person doing reality checks and using common sense would have departed from CO2 being much more soluble than O2 and N2 and deducted that there would be a much higher volume of CO2 outgassed from warming oceans than the volume of every other di-gases. Said that and as the part of the atmosphere that is CO2 is so small when compared to nitrogen and oxygen the conclusion is obvious: the ppmv of CO2 raises while the change in the other two remains negligible. No calculation is needed to reach this conclusion, just the perception of someone with discipline and no preconceived conclusions to ascertain. -
Composer99 at 00:43 AM on 15 December 2010The 2nd law of thermodynamics and the greenhouse effect
damorbel @ 220: You agree with four of the questions archiesteel puts to you; where agreement would seem to indicate agreement with some sort of greenhouse effect. And yet you appear to continue to maintain that such an effect is nonexistent, if your own questions such as:3/What is in your or anyone else's writing, that explains just how the presence of GHGs change a planets surface temperature from that in the absence of GHGs?
are anything to go by. I'm going to go out on a limb and suggest that the comment threads on the 2nd law of thermodynamics have for weeks been dominated by people (all of them doing a better job than I could) explaining to you just how, exactly, greenhouse gasses alter global surface temperatures (see KR's excellent summary @ 214, for example), and providing links (whether to other posts on this site or to other sites or the literature) showing how this effect can be, and is, directly observed to be taking place, and how its consequents (increase in global mean temperature, cryosphere mass balance decline, increase in ocean heat content, changes to migration patterss, animal & plant distribution, &c &c &c) are also observed to be taking place. -
robert way at 23:46 PM on 14 December 2010A new resource - high rez climate graphics
John's book is out? Where can you get it?Response: She means The Guide. My book (the paper version) doesn't come out till around April 2011 - the process of getting a real book published is glacial compared to online publishing. -
michael sweet at 23:09 PM on 14 December 2010Ice data made cooler
RSVP: Your calculation is riddled with additional errors that you have not noticed. See my post 39. The calculation is too difficult to do on a blog. The longer you go on the clearer it is that you do not know what you are talking about. You are legendary for the "waste heat" thread and continue to raise the issue of waste heat even though the site has dedicated over 400 posts to explaining heat to you. Stop doing the same thing here. My post 22 sums up the situation about outgasing of O2. Read it again. A qualitative answer is the best you will be able to get. Read the posts that we give you. O2 and N2 are different from CO2 because of their chemical properties, which you do not understand. Archiesteel @41 x2. Alan: your post 28 was useful to me. -
iana at 23:06 PM on 14 December 2010A new resource - high rez climate graphics
oops, scratch that- should have read your new book first - there it is! Thank you!Response: The "Human Fingerprints on Climate Change" graphic is definitely coming - that was what I considered the most important graphic in the booklet although the feedback I'm getting from people is that everyone loves the cherry tree. It's just a tree! (sorry, don't know why that gets to me). When I add the "Human Fingerprints" graphic to the list of graphics, I also want to update the basic rebuttal of "It's not us" (with James' permission). -
iana at 23:02 PM on 14 December 2010A new resource - high rez climate graphics
While I have no idea how to do it, I'd love to see a visualisation of the 'fingerprints' of man made warming. Thank you for your efforts to date. -
CBDunkerson at 22:52 PM on 14 December 2010The 2nd law of thermodynamics and the greenhouse effect
damorbel writes: "Half of the IPCC thesis is that the Earths albedo reduces the surface temperature when some simple physics familiar to all shows that this simply isn't true." Which is, of course, pure nonsense. Black asphalt gets hotter than white cement on a sunny day. Albedo directly impacts temperature. This is something children can understand, even without knowing the big words for it. It is also simple logic. The total amount of energy coming in and going out must be the same... ergo, the amount of energy reflected plus the amount of energy absorbed and then emitted as heat must equal the amount of energy striking the object... ergo, the more energy an object reflects the less it absorbs and the less heat it emits. Which is why absorptive black asphalt gets hotter than reflective white cement. Also: "The other half of the IPCC thesis is that gases that emit/absorb infrared can change the heat distribution in the atmosphere." Actually, they've been observed doing that. Kinda like saying that there is a thesis that something will fall if you lift it up off the ground and then let go of it. Sure, that's what the thesis says... because that's what is actually happening. -
Eric (skeptic) at 21:44 PM on 14 December 2010An Even Cloudier Outlook for Low Climate Sensitivity
#75, Pete, I took your (and others') advice and about the MERRA model at RC. I realized later that my "broader question" in #71 seems silly since one of the main purposes of modeling is to determine temperatures at each layer of the atmosphere. But looking at the equations for convection and radiation, I still don't see the conduction from GHG to nonGHG. Maybe it is so basic I missed it elsewhere in that pdf. -
RSVP at 21:15 PM on 14 December 2010Ice data made cooler
Alec Cowan #44 "you don't catch the difference between an ion and a di-gas." I have referred to O2 assuming oxygen occurs this way in nature. If I am wrong about this, please exlain. As far as the "calculation", I have simply applied laws of proportion to the problem (and yes, made a mistake by reading a value incorrectly from a table), but the idea here is what matters not the the result. The idea simply that as CO2 outgasses so do a lot of other things. Since this fact doesnt seem to seat well with some people, there has been an attempt to discover flaws in my calculation, and ignore post 33. Ironically, I am being accused of being politically motivated. Since when have you heard of a politician admitting a mistake? Again, if this last value is off by some astounding amount due to a huge blunder, no one has yet pointed it out. As I said, we could all learn something. Yes, water "boils" at 100 degrees C, however that would be pure water, and at sea level. Beyond that, I dont think much more accuracy is needed. However, there will always be someone who will take issue with something like this, and spin their poster miles looking for technical inaccuracies that ultimately have no practical significance to the vast majority. Yet this thread is filled with remarks of this sort. Not sure who they think they are fooling. -
damorbel at 20:17 PM on 14 December 2010The 2nd law of thermodynamics and the greenhouse effect
Re #219 Philippe Chantreau You wrote:- "I do not understand how that shows that temperature is not a measure of heat content." Again it is a matter of precision. Temperature is a measure of energy density, if you double the amount of energy in a kg of material you double its absolute (K) temperature; it is a simple as that. But if you do not specify the amount of material the temperature, for a given amount of energy, is completely unspecified. 'Quantity of material' can be (almost) anything, it can be a single atom or even smaller. A single atom can vibrate in three directions and the thermal energy, which is neither more nor less than the vibrational energy of the atom. Because a single atom vibrates in three directions, called degrees of freedom, the total energy of the atom is divided into three parts, one part in each degree of freedom. The relation between temperature and vibrational energy is called the Boltzmann constant In #219 you also wrote:- "If no thermal energy can be transfered by IR radiation from a cooler object to a warmer one, how does a radiant barrier work in a vacuum (they do work, and have engineering applications)? " Radiant barriers in simplest terms reflect energy, stopping it getting where it isn't want. Reflection is quite differnt from absorption, when reflecting radiation the temperature of a mirror is not changed (or changing). There is a further consequence of this 'non-absorption' of energy by reflection; a perfect mirror cannot emit any energy at any temperature. Real objects reflect partially and emit/absorb partially Yet further in #219 you wrote:- "Abut the second question, your answer is a little strange. Why only "thermal processes" (whatever that means) and IR radiation?" Again the distinction is in the detail. Thermal processes are generally considered to be those caused by vibrations in atoms and molecules, this includes thermal radiation since thermal radiation arises from the (thermal) vibration of electric charge. An example of non-thermal transfer of energy is evaporation of water and rainfall. Both of these processes arise from thermal energy but the way they happen is rather special since it has a lot to do with intermolecular forces that are not included in thermal processes. Another non-thermal process is convection. Convection is a very important heat transfer process in the atmosphere but works by bulk change in density, not at the molecular level. Temperature and heat are still important in these processes other energy processes are at work also. Some examples may appear to break 2nd Law; the Foehn wind is one. The exact working of the Foehn process is not simple since there are a number of energy processes occurring at the same time and the importance of each will be different in different situations. I want to revisit your #210, you wrote:- "The question is very clear, let me rephrase it: do you dispute that these gases absorb and emit IR in the stratosphere and that their radiative properties affect the temperature of the stratosphere? I made it very clear that the GHGs have radiative properties in the stratosphere but, just as on the surface, they do not affect the temeprature profile there. The temperature profile in the stratosphere (e.g. temperature increasing with altitude) is determined to a considerable extent by the radiative properties of oxygen, not the GHGs. -
damorbel at 18:47 PM on 14 December 2010The 2nd law of thermodynamics and the greenhouse effect
Re #218 archiesteel You wrote:- "Photons from the sun heat.... " Yes. "Assuming.... they emit IR energy, as described by black body theory " No. Just as objects like planets do not absorb 100% of the incident radiation from the Sun because a certain % (called the albedo) is reflected, neither is 100% radiated. What you should realise is that the % 'trapped' by a radiating planet is exactly the same as the % of the incoming radiation reflected as albedo. "Assuming ....IR radiation is absorbed by greenhouse gas molecules, ... "transparent" to visible light ...similarly, non-greenhouse gases such as O2 and N2 are mostly transparent to IR-range photons. Do you agree with this?" Yes "Assuming....to maintain thermal equilibrium, greenhouse gas molecules re-radiates the IR energy in a random direction ....Do you agree with this?" Yes "some of the re-radiated IR energy will escape to space, some will get back down to the surface, and some will be captured by other greenhouse gas molecules, continuing the absorbtion/re-radiation cycle. Do you agree with this?" Yes. Now answer my questions - please. 1/You argue, correctly in my opinion, that GHGs radiate equally, on average, in all directions. Do you also accept my argument that the scattering/reflection processes that cause the albedo is completely independent of the direction of arrival of the photons that are scattered? 2/In an 'Earth' atmosphere, but of pure CO2, can you tell me, on a scale of 1 to 100, what % of photons emitted at a height of 5km will reach the surface without being reabsorbed? 3/What is in your or anyone else's writing, that explains just how the presence of GHGs change a planets surface temperature from that in the absence of GHGs? -
HumanityRules at 16:56 PM on 14 December 2010An Even Cloudier Outlook for Low Climate Sensitivity
61 Albatross Agreed, let's talk about the science. The scatterplots. The observational data obviously has a lot less data points than the model. Importantly few at the extremes of deltaT. Do those few data points have a larger impact on the slope of the graph than the pile of data points in the middle? Is this part of the limitations of this being only 10 years of analysed data? What are the specific limitations of only having 10 years data? -
Renewable Baseload Energy
quokka - That's a very interesting link (if off-topic for here). Do you know if any of the micro-reactor designs now in the US/European planning stages are set for high temps like those Russian designs? -
Pete Dunkelberg at 14:23 PM on 14 December 2010An Even Cloudier Outlook for Low Climate Sensitivity
Eric (skeptic) #71 My broader question is is GHG warming of the rest of the atmosphere in any model? Eric, any day now I expect to read that you are skeptical of whether climate scientists remember to put their pants on in the morning. But seriously, why not ask some of these questions over at RC? -
Eric (skeptic) at 14:03 PM on 14 December 2010An Even Cloudier Outlook for Low Climate Sensitivity
A brief followup: the pdf indicates that the lapse rate is used as one of the predictors for the linear calculation of satellite sensor bias parameters. I take that to mean that lapse rate (derived from the model?) is used as an independent variable in a linear equation which calibrates the sensor. -
Eric (skeptic) at 13:54 PM on 14 December 2010An Even Cloudier Outlook for Low Climate Sensitivity
#72, scaddenp, I'm trying to find the answer to my general question myself, it has something to do with optical depth or thickness I think. For that particular AGCM my understanding is that the model is used to assimilate satellite measurements so they can be used for broader climate and weather studies such as Dessler's. That means it assimilates just the satellite measurements (radiation) and I'm not sure that lapse rate can be derived directly from those measurements (I could be wrong). But looking at the convection system equations, I guess the idea is that because the temperatures are calculated at each layer in the model, that temperature gradient does in fact represent the lapse rate in discrete steps. So I guess it is calculated within the model after all. -
Composer99 at 13:38 PM on 14 December 2010A new resource - high rez climate graphics
Now that John has mentioned the graphics would look good on a billboard, I think it's time to see if getting a SkS graph on a billboard can be done. -
scaddenp at 13:14 PM on 14 December 2010An Even Cloudier Outlook for Low Climate Sensitivity
I hope Kooti will respond with some authority here but quickly looking at the pdf, I dont follow you. If lapse rate is an input (no sign of this being the case), how can lapse rate be used for quality check? Convection system is described. -
muoncounter at 13:08 PM on 14 December 2010A new resource - high rez climate graphics
John, are you familiar with the Rimfrost website? Java applet with monthly and seasonal temp selection, CO2 concentrations from multiple sites, sunspots, linear and curve fits, etc. Fun! -
muoncounter at 13:05 PM on 14 December 2010What would happen if the sun fell to Maunder Minimum levels?
#102: "As for the cooling that is supposed to happen," No guarantees there. We came through the quietest sun in decades and we warmed. See the thread Its (not) the sun. -
muoncounter at 13:01 PM on 14 December 2010What would happen if the sun fell to Maunder Minimum levels?
#100: "always just a few years away... " All will be well once the magic clouds arrive. Just keep saying, "there's no place like home" and it will happen. Wonder who will play the wizard? -
Mikemcc at 13:00 PM on 14 December 2010A new resource - high rez climate graphics
I take it we can use them when arguing on message boards without having to mither you for every occasion, provided we also provide the link to you as well? I wouldn't want to burden you with too much to answer to!Response: Absolutely, do please use the graphics elsewhere and no need to ask (that was the point of the Creative Commons licence). Now that you bring it up, it might be helpful if I also include the most relevant link for people to link to if using the graphic in a forum. Eg - for the solar activity graphic, a good link is:
http://www.skepticalscience.com/solar-activity-sunspots-global-warming.htm -
Polar Bear at 12:40 PM on 14 December 2010A new resource - high rez climate graphics
Thankyou.I used to cringe at the thought of looking at a simple graph.I have caught on and wish to move on..I think your work will be Very helpful Jean M -
Eric (skeptic) at 12:39 PM on 14 December 2010An Even Cloudier Outlook for Low Climate Sensitivity
In http://gmao.gsfc.nasa.gov/pubs/docs/Rienecker369.pdf (the model Dessler used to get the top chart in the post) it seems like the AGCM has no mechanism to use convection and latent heat transfer to estimate the lapse rate. Instead the lapse rate seems to be an input to the model. It seems to me that lapse rate is the most direct determiner of cloud amounts and cloud feedback lapse rate controls convection. My broader question is is GHG warming of the rest of the atmosphere in any model? This question came to mind reading the explanation of GHG warming on the other thread which didn't take into conduction from the GHG to the non-GHG. My understanding is that this happens much more often than the GHG re-emitting radiation that it just received. The equations in the model above don't appear to have that conduction, hence the need to input lapse rate. I don't know how any model can calculate lapse rate without conduction. -
scaddenp at 12:36 PM on 14 December 2010Guest post: scrutinising the 31,000 scientists in the OISM Petition Project
I think the question (108) has better answer. "Competent" to my mind means working in the field and publishing in proper peer-reviewed journals on climate(ie not E&E). Wikipedia has this list. Now some of those on list, certainly dont fit my category of "competent". Some are industry shills. However, most in fact have a nuanced position. Acceptance of physical reality but alternative theories for PARTS of climate - eg the value of climate sensitivity, relative role of GHG to other natural factors etc. Mostly they are in different class from the denialists who will simultaneously hold "its not happening, its not us, its good for us" - ie "I'll believe anything that support no change in policy". Note the number of "emeritus" class people - now that's a warning. I'd say Spenser, Lindzen (when talking to other scientists), Christy, maybe Chylek as credible people. I would read published papers on the subject from them with some respect. Many of the others are also people I would read when publishing in their respective fields as they are certainly competent there. -
quokka at 12:32 PM on 14 December 2010Renewable Baseload Energy
Here is an interesting idea for getting rid of coal - Coal2Nuclear. Briefly put, the idea is to retain the turbines, switch yards etc of existing coal plants and replace the coal boilers with small modular reactors. I don't know how feasible the idea is and it depends on the commercial availability of small modular reactors which are 7 - 10 years off. Nevertheless it certainly presents an interesting possibility for very economically giving coal the flick. It is just a thought, and I do not present it as a solution at this time as is commonly done for technologies such as enhanced geothermal which in reality is at least as far, and very possibly further away as a commercial proposition.Moderator Response: [Daniel Bailey] Fixed link
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