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Comments 102551 to 102600:

  1. Stratospheric Cooling and Tropospheric Warming
    Sphaerica 39 I have added a footnote explaining that the fictitious planet that I am using is a physical impossibility. I stated further that it would be difficult to explain this basic concept with a more realistic and complex model. Bob
  2. We're heading into an ice age
    More for NQuestofApollo to read, this time concerning Himalayan glaciers : Go here, here, and here.
  3. Stratospheric Cooling and Tropospheric Warming
    Bob, I remember seeing a completely different explanation for stratospheric cooling, and one which is easier to understand and makes more sense to me (as long as one understands what heat really is, and how energy is transferred between molecules in a gas). The gist of it was that in the more dense troposphere, a CO2 molecule is likely to absorb IR (in the appropriate band), and it is particularly likely to then collide with the more numerous O2 and N2 molecules (before simply re-radiating the energy away in the same band). In the collision, it transfers the energy (gained through IR) to the O2/N2 as translational kinetic energy, and in so doing heats the atmosphere. In the more rarefied stratosphere, CO2 is more likely to do the opposite, colliding with an O2 or N2 molecule, becoming excited by the collision (gaining vibrational energy), and then emitting the energy gained away as IR. Thus, increased amounts of CO2 warm the troposphere while cooling the stratosphere; they cause IR to primarily be an absorption mechanism in the troposphere, and an emission mechanism in the stratosphere. In this explanation, it's not merely the blocking of the CO2 IR band in the troposphere which causes the cooling, but rather an active effect of CO2 within the stratosphere itself. Can you reconcile the differences in the explanations? Is this description wrong? Or are they both accurate and true?
  4. Renewable Baseload Energy
    Rob Honeycutt, "Did you miss the part where Steven Chu just stated that China is going to be 20% renewables by 2020?" Most of China's renewables are hydro. I stated in some posts, and obviusly need to say it in every post, that I am referring to non-hydro renewables when I say renewables cannot provide baseload generation. I should also say that biomass and geothermal, in volcanic areas but not Australia, can provide baseload generation but in insignificantly small quantities. The thread is about baseload. So the comment about China targeting 20% renewables is off topic.
  5. 2nd law of thermodynamics contradicts greenhouse theory
    damorbel as I said and you apparently did not read, part of the spectrum. My impression is that you're not much confident with these simple physical concepts but you presume you know better.
  6. 2nd law of thermodynamics contradicts greenhouse theory
    Re #251 you wrote:- " I would strongly suggest that you read the following, by Dr. Roy Spencer, climate skeptic, which directly addresses this topic:" I've read Roy Spencer on this matter, he's wrong. He uses the 'insulation' argument for CO2 etc. keeping heat 'in' (the atmosphere). This insulation/blanket argument is invalid because insulators only contain heat when it is in the container already, either because it was put there from outside, like putting hot soup in a flask, or there is a source of heat like combustion or radioactivity 'contained' by the insulation. Heat that arrives from outside the container, like the Sun/Earth arrangement is just as effecively kept out of a container (flask etc.) as it is kept inside. Eventually the contents of an insulated container revert to ambient temperature, your soup or coffee gets cold and your ice cream melts. What a shame!
  7. Renewable Baseload Energy
    Peter Lang #215 I've asked you questions about things like synergisic effects, distributed generation, efficiency gains in the past, but you have not answered any of these questions. They're important issues which need to be considered when assessing electricity generation resources, but you don't seem to want to do so. I haven't actually expressed any opinion on nuclear energy, so attacking my position as ideologically driven kneejerk anti-nuclear seems a bit of a stretch. However, from the fact that you haven't answered my perfectly reasonable questions, I can only assume that you won't because you have something to hide.
  8. Renewable Baseload Energy
    The issue is "can baseload power come from renewables". The nuclear issue is separate from "can baseload come from renewables". Nuclear proponents have already hijacked several threads with their claims. Everyone agrees that nuclear can generate baseload energy if it can overcome its other problems. I am tired of the unsupported claims from nuclear proponents, see the linked thread. I have seen their claims more than once and do not need to see them repeated again here. I am agnostic about how much nuclear will end up being best, but it is tiring to have these wild claims repeated again and again.
  9. Stratospheric Cooling and Tropospheric Warming
    Re OP It says:- "a fictitious planet with an atmosphere consisting of carbon dioxide and an inert gas such as nitrogen at pressures equivalent to those on earth. This atmosphere will have a troposphere and a stratosphere" The stratosphere is caused by the warming effect of UV energy absorbed by O2 & O3; this couldn't happen in an atmosphere free of O2; no other atmospheric gas absorbs UV in the same way. This warming due to UV absorption produces a classical temperature inversion, suppressing convection; the result is the well known absence of storms etc. in the stratosphere. The absence of storms is one of the reasons why airliners fly there.
  10. 2nd law of thermodynamics contradicts greenhouse theory
    damorbel - Your physics are so far off it is difficult to know where to start. But I would strongly suggest that you read the following, by Dr. Roy Spencer, climate skeptic, which directly addresses this topic: Yes, Virginia, Cooler Objects Can Make Warmer Objects Even Warmer Still A quote from this, involving heated plates as a thought experiment: "Since the temperature of an object is a function of both energy gain AND energy loss, the temperature of the plate (or anything else) can be raised in 2 basic ways: (1) increase the rate of energy gain, or (2) decrease the rate of energy loss. The temperature of everything is determined by energy flows in and out, and one needs to know both to determine whether the temperature will go up or down. This is a consequence of the 1st Law of Thermodynamics involving conservation of energy."
  11. Stratospheric Cooling and Tropospheric Warming
    Andy - 35 It wouldn't be difficult for Gavin to explain if he was explaining it to a college sophmore Physics major. He would talk about the absorption spectrum as I have done. In my opinion, you cannot explain it without talking about the absorption spectrum which is what Gavin is trying to do in the referenced link.
  12. 2nd law of thermodynamics contradicts greenhouse theory
    Re #248 CBDunkerson you wrote:- "damorbel #247: "Tom they would be absorbed by any 'target'." That's a yes. Ergo, global warming theory does not violate the second law of thermodynamics." You are going too fast. Since emitting (GH) gases absorb also there is no chance that any imbalance in thermal energy transfer will arise as described by 'back radiation' (i.e. W/m^2, J/s/m^2) as claimed by Trenberth. Not just 'insufficient' to cause 33K increase in surface temperature but none at all., the thermal energy transfer is going from the surface to the troposphere, cooling the surface as it goes. You must realise that with a full transparent atmosphere (no GHGs) the cooling radiation would all come from the surface, so what's the big deal? The surface would have just the same temperature it has now.
  13. Stratospheric Cooling and Tropospheric Warming
    This 1950s video is fascinating, from the days when people knew how to explain things using animation: http://lasp.colorado.edu/igy_nas/flash_videos/theInconstantAir.html I think I got the link from Grumbines blog a few months ago.
  14. 2nd law of thermodynamics contradicts greenhouse theory
    Re #240 Riccardo you wrote:- "any body may behave like a blackbody in a frequency range and not in others. In particular, the earth surface is very near a blackbody in the IR range of interest." Not so. IR is just a colour the same as red, yellow, green etc. and there is an albedo (reflection) in the IR also. The IR emissions from H20, CO2 etc. do not follow the smooth black body emission spectrum, instead the spectrum is highly irregular meaning that, for substantial parts of Earth's emission spectrum there is no radiation from the GHGs. Now you could argue that radiation from Earth 'fills in the gaps' but you will also have to explain why the material that reflects the sunlight to give Earth an albedo doesn't also reflect radiation originating in coming from Earth. There is no real 'one way' reflection effect, what you have for the ladies changing room is a cunning lighting effect that gives the impression of a 'one way' mirror. The cause of Earth's 30% albedo also causes a reflection of 30% (inwards) of the radiation coming out from the planet. That is why the temperature of a planet like Earth is independent of the albedo.
  15. 2nd law of thermodynamics contradicts greenhouse theory
    damorbel #247: "Tom they would be absorbed by any 'target'." That's a yes. Ergo, global warming theory does not violate the second law of thermodynamics. Now you are just quibbling about the magnitude of the effect. Which, as various people have pointed out, is a measured fact. Heck, Fourier made a pretty good stab at estimating it nearly two hundred years ago when he discovered the temperature discrepancy and first proposed what we now call the greenhouse effect as a possible explanation.
  16. 2nd law of thermodynamics contradicts greenhouse theory
    Re #245 Tom Dayton, you wrote:- " I am pleased to see your agreement that photons from a cooler source are indeed absorbed by a warmer target" Tom they would be absorbed by any 'target'. But do you agree that they are absorbed by adjacent CO2 (H2O, CH4 etc.) more or less at the altitude where they are emitted? Or do they make it to the Earth's surface as 'backradiation', as in Trenberth's diagram? Further, do you think the cold photons raise the surface temperature 33K from 255K to 288K? And finally, what would be the average surface temperature without the H2O & CO2 etc.?
  17. Stratospheric Cooling and Tropospheric Warming
    Some further RealClimate articles worth reading Why does the stratosphere cool when the troposphere warms? (In which Gavin Schmidt shows that explaining this effect is not simple, even for him.) The sky IS falling (Which includes a link to the ESPERE article that I referenced in post #5 above) The wisdom of Solomon. (Discussing, among other things, the role of the small quantities of water vapour in the stratosphere.)
  18. Ice age predicted in the 70s
    If you want to read the Shackleton paper yourself, instead of taking what William Connelly says at face value, you can read the abstract here: http://www.ncbi.nlm.nih.gov/pubmed/17790893 "Science. 1976 Dec 10;194(4270):1121-32. Variations in the Earth's Orbit: Pacemaker of the Ice Ages. Hays JD, Imbrie J, Shackleton NJ. Abstract 1) Three indices of global climate have been monitored in the record of the past 450,000 years in Southern Hemisphere ocean-floor sediments. 2) Over the frequency range 10(-4) to 10(-5) cycle per year, climatic variance of these records is concentrated in three discrete spectral peaks at periods of 23,000, 42,000, and approximately 100,000 years. These peaks correspond to the dominant periods of the earth's solar orbit, and contain respectively about 10, 25, and 50 percent of the climatic variance. 3) The 42,000-year climatic component has the same period as variations in the obliquity of the earth's axis and retains a constant phase relationship with it. 4) The 23,000-year portion of the variance displays the same periods (about 23,000 and 19,000 years) as the quasi-periodic precession index. 5) The dominant, 100,000-year climatic [See table in the PDF file] component has an average period close to, and is in phase with, orbital eccentricity. Unlike the correlations between climate and the higher-frequency orbital variations (which can be explained on the assumption that the climate system responds linearly to orbital forcing), an explanation of the correlation between climate and eccentricity probably requires an assumption of nonlinearity. 6) It is concluded that changes in the earth's orbital geometry are the fundamental cause of the succession of Quaternary ice ages. 7) A model of future climate based on the observed orbital-climate relationships, but ignoring anthropogenic effects, predicts that the long-term trend over the next sevem thousand years is toward extensive Northern Hemisphere glaciation. PMID: 17790893 [PubMed] LinkOut - more resources "
  19. Climategate: Impeding Information Requests?
    dhogaza @ 77 No clarification required as far as I am concerned. Your meaning was quite clear. I will add that the ICO has ruled out an investigation into an offence under R19/S77. What remains are the Decision Notices(DN). These are findings of any appeal to the ICO. Decision Notices may require the public authority to release information or may state that they did not fulfil their legal obligations under FoIA/EIR, or even endorse the response of the public authority. The public authority can appeal to a Tribunal (court) or comply with the DN. DNs are not findings of any felony. However, ignoring a DN could lead to contempt of court. Anyone who tries to argue that it is or wiill be a "whitewash" is merely demonstrating ignorance of the legislation.
  20. Stratospheric Cooling and Tropospheric Warming
    Bob #26 Yes, it does help. Thanks. I think I can put the pieces together a bit better, now, putting you post in the context, btw. It was a good basic explanation. Thanks Spaceman Spiff too.
  21. We're heading into an ice age
    NQuestofApollo says... "why should I assume that CO2 CAUSES global warming?" Because it's basic physics? Actually, the globe has not been warming for the past 10,000 years. If you look at the Holocene optimum we've been slightly cooling over that period. It's only in the past 100 years that we've reversed that trend. Honestly, this site provides information that responds to everything you've said here much better than I can in a short post. I would urge you to take some time to read some of the articles and follow the cited sources.
  22. We're heading into an ice age
    NQuestofApollo, your post gives lots of opportunity for everyone here to point out your misunderstandings, but I would like to start with your first assertion : "Remember Michael Mann's "hockey stick graph" - the one trotted out by Al Gore and the IPCC as proof positive that AGW exists? If in fact the Earth is warming - why did Mann feel the need to concatenate two different data sets?" You should read further on this website (by using the 'Search' box in the top left) but I will start you out : Go here, here, here and here. If no-one else can be bothered to point you in the right direction for your other misinformed points (and I wouldn't blame anyone else for not wanting to go over all this again), I will return to this later.
  23. We're heading into an ice age
    NQuestofApollo... You've posted such a long list of baseless information that it's a little hard to respond. Let me take the "31,000 scientists" issue first. We are all aware of the Oregon Petition. What you are ignoring about it is that figure requires a denominator to have any meaning at all. The petition defines "scientist" as anyone with a BS or equivalent. That encompasses nearly 30,000,000 people in the US alone. You can likely double that number or more looking outside the US. So, even at best you are presenting a figure that is about 1/10th of one percent. If you poll actual working climate scientist who are currently working in this field you get quite the opposite number. Doran 2009 shows that 97% of climate scientists believe that climate change is real.
  24. Spaceman Spiff at 04:27 AM on 2 December 2010
    Stratospheric Cooling and Tropospheric Warming
    Bob Guercio @28: It is possible that the following may be an important consideration here: most of the stratosphere, unlike most of the troposphere, is not in local thermodynamic equilibrium (LTE). i.e., the rates of collisional processes do not exceed greatly spontaneous decay rates of energetically excited molecules, as they do within gases for which LTE is an excellent approximation. The heating rate within the stratosphere should be dominated by ozone dissociation via solar photons from above. However, by increasing the CO2 content of the stratosphere, you mostly increase the rate of that gas' ability to radiate energy away via collisional excitation followed by spontaneous photon emission. This tips the heating-cooling balance to lower temperatures. I know I've a few technical papers on the subject sitting on my laptop at home, and I'll try to remember to read them tonight.
  25. NQuestofApollo at 04:18 AM on 2 December 2010
    We're heading into an ice age
    scaddenp - obliviously diamonds are not emissions, but then neither is Carbon. I was being sarcastic to make the point that any reference to "Carbon" emissions is disingenuous. Unfortunately, this short hand is causing (otherwise intelligent people) to claim that "carbon emissions from cars are combining with ozone and causing a depletion in the ozone layer". Daniel, I appreciate all of the information you provided here and would like to challenge you on your definition of a "competent scientist". Remember Michael Mann's "hockey stick graph" - the one trotted out by Al Gore and the IPCC as proof positive that AGW exists? If in fact the Earth is warming - why did Mann feel the need to concatenate two different data sets? If I wanted to prove that sports scores have been increasing over the last 100 years and I take baseball scores for the first sixty years and plot them - then I take basketball scores for the last 40 years and tack them on the end of my graph, would my graph be taken seriously? Supporting articles here and here. Distressingly, this is the same IPCC that "misread" the year the Himalayan glaciers were "likely to disappear" due to global warming: Mr Cogley says it is astonishing that none of the 10 authors of the 2007 IPCC report could spot the error and "misread 2350 as 2035". IPCC error Equally distressing is the suggestion that they may have done so on purpose. IPCC error intentional Here's a question I literally cannot find an answer to: How many scientist work for the IPCC and what are their names? I've heard 1000, I've heard 2000 - yet, I cannot find a comprehensive list of the people involved in promoting AGW. On the other hand, here is a list of over 31,000 scientist that think AGW is a bunch of bunk. All their names are listed - right there. (I know, I know - they were ALL bought off by Big Oil.) Petition Project There has been some chatter on this site about not looking at thermometer reading to assess the global warming situation (too bad nobody mentioned that to Michael Mann) - I've been told to look at the sea ice extent. So, I have - it has increase for the last three years. The counter to this point is that the ice is thin - but, of course young ice is thin. The point is that the extent has NOT receded in the last three years. Now, how can that be with all of that accumulated, globe warming carbon? Sea Ice Extent Also, if accumulated CO2 definitively causes the globe to warm, why did they think the globe was cooling for the 30 years prior to the 1970s? But, this, I think, is the primary question: since CO2 will increase as the globe warms (due to melting, CO2 containing glaciers), why should I assume that CO2 CAUSES global warming? Sure the globe has been warming (for the last 10,000 years), sure there is more CO2, but what if you have your cause and effect relationship inversed?
  26. Stratospheric Cooling and Tropospheric Warming
    Albatross - 30 That's a fantastic writeup from RealClimate which is the cadillac of Climatology sites. If it's there, you can believe it. In any case, it's going to take me at least another reading to digest that. Did you look at Part II! It gets very heavy. Thanks for that recommendation. Bob
  27. Spaceman Spiff at 04:00 AM on 2 December 2010
    Stratospheric Cooling and Tropospheric Warming
    Bob Guercio @27: Of course, it wasn't my intent not to add something substantial to understanding. However, the concept of an increasing emissivity of the stratosphere hadn't been mentioned in the above discussion. My post did not ignore the role of the absorption bands (or the complementary atmospheric window in your example) -- in fact they are key in describing the spectrum of radiation emerging from the troposphere and thereby the means by which the heating rate within the stratosphere changes. However, I should have clarified my point that the tropospheric emission diminishes within the C02 absorption band region center on 667 cm^{-1}. And, apparently, the increased emission arising from below the stratosphere over wavelengths corresponding to the ozone absorption band (centered on 1050 cm^{-1}) doesn't add enough to the heating rate budget of the stratosphere to offset the decreased heating rate there due to the diminished intensity of radiation within the main C02 band emerging from below. But it looks as though your example didn't want to consider this complication (?). In any case, I do appreciate your efforts!
  28. A basic overview of Antarctic ice
    #80: "one of the objections against Rignot et al. 2008 was: “Corr and Vaughn report that volcanic activity beneath the Antarctic ice may have increased the flow rate of some of the region's largest glaciers.”" Ouch. You've quoted directly from the SPPI denial site. Unfortunately for that objection and any credibility that SPPI may once have had, the layer depth dates the eruption at 207 BC±240 years. Hardly a factor in ice loss in this decade, century, millenium or any other relevant time period.
  29. Stratospheric Cooling and Tropospheric Warming
    Hi Bob, You mentioned Gavin Schmidt, and that reminded me of this informative post over at RealClimate. Some of the content is relevant here.
  30. A basic overview of Antarctic ice
    And the goal post shift, again (re #80 and #81). From the main post (first sentence): "Skeptic arguments that Antarctica is gaining ice frequently hinge on an error of omission, namely ignoring the difference between land ice and sea ice." And later, "All the sea ice talk aside, it is quite clear that really when it comes to Antarctic ice, sea ice is not the most important thing to measure." And then, "There is of course uncertainty in the estimations methods but multiple different types of measurement techniques (explained here) all show the same thing, Antarctica is losing land ice as a whole, and these losses are accelerating quickly." Now we have people talking about volcanoes explaining the loss of land ice, a swipe at the AOGCMS, a link to the questionable SPPI (the much debunked Monckton is their chief policy adviser), talk of how droughts in Australia is explained by changes in snowfall over portions of the EAIS (which is misleading and cherry picking as I will demonstrate below), and the old-time favourite "X can be explained by internal climate modes/variability" (which is also refuted by the study below). It is relevant that at least one prominent "skeptic"/contrarian (McIntyre) thinks that teleconnections are "voodoo science"...I digress. If someone, especially a “skeptics” makes claims about a paper, it is always best to go to the source. Here , again, we have an example of “skeptics” distorting the results from a paper to suite their means. From the abstract from a recent paper in Nature by van Ommen and Morgan (not et al.). “Here we report a significant inverse correlation between the records of precipitation at Law Dome, East Antarctica and southwest Western Australia [edit—not all of Australia] over the instrumental period, including the most recent decades. This relationship accounts for up to 40% of the variability on interannual to decadal timescales [edit-- not all of the variability], and seems to be driven by the meridional circulation south of Australia that simultaneously produces a northward flow of relatively cool, dry air to southwest Western Australia and a southward flow of warm, moist air to East Antarctica. This pattern of meridional flow is consistent with some projections of circulation changes arising from anthropogenic climate change. The precipitation anomaly of the past few decades in Law Dome is the largest in 750 years and lies outside the range of variability for the record as a whole, suggesting that the drought in Western Australia may be similarly unusual.” So on the one hand we have Arkadiusz @80 quoting the researcher to state that the southwestern Australian drought was well outside the range of natural variability, and then another "skeptic" (BP) in the next post is claiming that multi-decadal natural variability is at play. Please do make up you minds guys. This is just yet another example of the incoherence and inconsistency of arguments made by "skeptics". In fact, the usual suspects on this thread seem to be trying to fling as much mud as they can and hope that something sticks, and to try and distract us all from the science and issue at hand. Well that might work at WUWT, but not here.
  31. Stratospheric Cooling and Tropospheric Warming
    Guys, I'm doing a lot of talking here but let it be known that although I am educated in Physics, I am not an expert at what we are talking about. In fact, I have never been a scientist. I'm hoping that someone jumps in to corroborate all of this because I don't want to mislead. This is what I actually hate about the Internet. Often it's hard to tell fact from fiction and I find myself somewhat doing now what I always rail against. Bob
  32. Stratospheric Cooling and Tropospheric Warming
    Spaceman Spiff - 25 With respect to Gavin's comment on emissivity and absorptivity, I think Gavin is saying that until the steady state is reached, the emissivity of the stratosphere is greater than the absorptivity because it is emitting more than it is absorbing. When the steady state is reached, the emissivity equals the absorptivity.
  33. Stratospheric Cooling and Tropospheric Warming
    Spaceman Spiff - 25 I'm not 100% sure but I think you are saying only what other explanations on the web say. You must consider the absorption spectrum which includes the absorption band and the atmospheric window. Bob
  34. Stratospheric Cooling and Tropospheric Warming
    Alexandre - 24 In keeping with my ridiculously simple model: In the steady state the amount of IR entering the stratosphere equals the amount leaving it. Now CO2 molecules are constantly gaining and losing energy. Some gain, some lose, this goes back and forth etc. In the steady state, the number gaining at any instant equals the number losing. Now suddenly there is less IR energy coming into the stratosphere from the troposphere. At this time, energy at the initial rate is still leaving the stratosphere going into space but less is coming in. Not all the molecules that have lost energy can get replenished because the necessary energy is no longer there. The energy leaving must diminish to equal that coming in for the steady state. Does this help? Bob
  35. Renewable Baseload Energy
    With all due respect to the great moderators here, I don't think a conversation regarding baseload power can be carried on without also discussing nuclear. It's a little like having one hand tied behind your back. Peter @ 187 said, "They are not viable and probably never can be (at more than about 10% of the total generation)." Did you miss the part where Steven Chu just stated that China is going to be 20% renewables by 2020?
  36. Spaceman Spiff at 02:50 AM on 2 December 2010
    Stratospheric Cooling and Tropospheric Warming
    As Gavin Schmidt mentioned above, by increasing the CO2 content of the atmosphere (in the stratosphere as well as the troposphere), the emissivity of the stratosphere (which is rather low due its low column density of gases) increases. The heating rate of the stratosphere depends on what energy it is able to absorb from below (the troposphere) and above (the Sun) in wavelength bands that its gases (mainly O3 and CO2) can efficiently absorb. From the point of view of the stratospheric gases that can absorb radiation from below, they see less radiation emerging from below due to the enhanced tropospheric opacity there (the effective emitting layer moves to higher altitudes where the T and thus thermal emission are lower). At the same time, the stratosphere can emit more efficiently with the enhanced CO2 content (the C02 column density there is small enough that very few wavelength bands are "saturated"). Thus the stratosphere T drops to re-establish heating(photo-absorption rate)--cooling(photo-emission rate) balance. I might be missing some of the details, but I think the above captures the gist of what happens.
  37. Stratospheric Cooling and Tropospheric Warming
    Bob #23 That part also helps me understand. More energy is now outside the absorption band of the stratosphere, and goes right through it. But that's that other part, about CO2 emiting more than absorbing, that I do not understand. I've seen this already somewhere else. In a similar version of the explanation, they say the CO2 absorption/re-emission helps "conduct" the heat upwards in the stratosphere, instead of trapping it. This part is frankly beyond my reach. Maybe it's something that's only fully understandable if you put together all the relevant physics and run the model... :-) In this case, we could only partially understand it with intuitive conceptual explanations.
  38. Berényi Péter at 02:42 AM on 2 December 2010
    2nd law of thermodynamics contradicts greenhouse theory
    #243 KR at 01:46 AM on 2 December, 2010 that would be cherry-picking If OHC is supposed to be the true indicator of global warming and we have only seven years of reliable OHC data, then it is not cherry-picking to use what we have, is it? What is more (and it is independent of MEPP), even if we assume heat is accumulating in the climate system on an annual rate of 1.45×1022 J, it takes more than 300 years to warm the ocean up by 1°C. It is clearly inconsistent with a 2+°C warming by the end of this century.
  39. 2nd law of thermodynamics contradicts greenhouse theory
    damorbel, like CBDunkerson (his last three paragraphs), I am pleased to see your agreement that photons from a cooler source are indeed absorbed by a warmer target. So you agree that the greenhouse gas effect does not violate the second law of thermodynamics, which is the topic of this thread, right?
  40. Renewable Baseload Energy
    @moderator: so sorry, I only now saw your requests (that's what happens when you go through "Recent Comments" instead of the actual threads...). I'll refrain from pushing the subject further here. Anyway, I've pretty much said everything I needed to say about Peter's aggressive sales pitch. I can't stand his not-so-veiled insults towards those who *dare* think renewables also have a place in the future energy mix. As for their links, at this point it should be considered blogspam for Brave New Climate. When pretty much all of one's references come from a couple of web sites, it's usually a sign you're pushing some sort of agenda...
  41. Renewable Baseload Energy
    "I'll just add that renewables cannot do the job at any cost and are unlikely to ever be able to." This is other examples of why we can't take you seriously. Renewables are already providing significant amounts of power to the grid, and their large-scale deployment has barely begun. We're not even talking about technologies that might be feasible 20-30 years from now, such as Orbital Solar. When you speak in such absolutist terms you make it clear this isn't a rational argument on your part, but a sales pitch that exaggerates the benefits of nuclear and the drawbacks of renewables.
  42. Renewable Baseload Energy
    @Peter Lang: "Talk about ideological - what is more ideological than anti-N and pro-renewables at any cost?" Peter, I think one of the reasons people here are reacting negatively to you Nuclear sales pitch is that, according to you, anyone who's not 100% behind Nuclear as the *only* solution is anti-nuclear. That is propagandist rhetoric at its ugliest. It seems to me you would have much more success by advocating for nuclear alongside renewables. It may go against your ideals/mission, but which is best: sticking to your guns and losing, or making compromises and achieving partial success? Think about it.
  43. Berényi Péter at 02:19 AM on 2 December 2010
    A basic overview of Antarctic ice
    #80 Arkadiusz Semczyszak at 01:21 AM on 2 December, 2010 [drought - Australia, the increase in snowfall - Antarctica] If Snowfall increase in coastal East Antarctica is linked with Australian drought indeed and Australian drought has nothing to do with AGW, then East Antarctic snowfall is also due to multi-decadal variability alone, isn't it?
  44. 2nd law of thermodynamics contradicts greenhouse theory
    In my previous post, "degrees of freedom will override climate forcings to maintain the status quo" is not a quote, but rather my interpretation of a number of postings on this subject. My apologies - I don't mean to put words into other peoples mouths.
  45. 2nd law of thermodynamics contradicts greenhouse theory
    Berényi - You are correct, I should have used the term "steady-state", rather than "thermodynamic equilibrium". However - the essential I extract from your post is your statement that "...there is a strong tendency to counteract climatic effects of CO2, but MEPP would not allow any change which would amplify it". In other words, you claim that there is only negative feedback, not positive feedback to a CO2 forcing. Sorry to say, the data proves this not to be the case. Feedback is positive, your assertion is quite simply not supportable. MEPP is either not a correct description or it does not have the effects you claim. You have been pointed to before, and have failed to address this issue with your MEPP claims. You keep saying that "degrees of freedom will override climate forcings to maintain the status quo", and that is observationally, patently not the case. As to your claim that the last 7 years disprove CO2 forcing, that would be cherry-picking - if this holds for 20-30 years, and acquires statistical significance, then we have something worth discussing.
  46. Stratospheric Cooling and Tropospheric Warming
    Let me add something to all this. The following passage came from: http://www.atmosphere.mpg.de/enid/20c.html _________________________________________________________________ Cooling due to the greenhouse effect The second effect is more complicated. Greenhouse gases (CO2, O3, CFC) absorb infra-red radiation from the surface of the Earth and trap the heat in the troposphere. If this absorption is really strong, the greenhouse gas blocks most of the outgoing infra-red radiation close to the Earth's surface. This means that only a small amount of outgoing infra-red radiation reaches carbon dioxide in the upper troposphere and the lower stratosphere. On the other hand, carbon dioxide emits heat radiation, which is lost from the stratosphere into space. In the stratosphere, this emission of heat becomes larger than the energy received from below by absorption and, as a result, there is a net energy loss from the stratosphere and a resulting cooling. Other greenhouse gases, such as ozone and chlorofluorocarbons (CFC's), have a weaker impact because their concentrations in the troposphere are smaller. They do not entirely block the whole radiation in their wavelength regime so some reaches the stratosphere where it can be absorbed and, as a consequence, heat this region of the atmosphere. _________________________________________________________________ This passage absolutely drove me crazy because I didn't understand it. I now understand it because I know that it is only part of the story. What bothered me was with regard to what happens after the earth heats up and reaches a steady state with a higher tropospheric temperature. Of course, this presumes stabilization of greenhouse gases but nevertheless, in the steady state the same amount of IR energy is going to be entering the stratosphere as before the CO2 concentration increased which caused the temperature to increase. This is necessary because conservation of energy requires that the solar energy entering the troposphere from the sun must equal the IR energy leaving the troposphere since the solar energy entering did not change. If the same amount of IR energy is entering the stratosphere from the troposphere, why doesn't the temperature of the stratosphere return to what it was before all this started. The reason is that more of this energy is in the atmospheric window which does not react with CO2 and less is in the absorption band which does react with CO2. So less in the absorption band than before means less energy reacting with the CO2 and a permanent lowered temperature. The stratosphere is also cooler because of the thinning of the ozone layer but this is relatively easy to understand and is explained in the referenced website. Bob __________________
  47. Stratospheric Cooling and Tropospheric Warming
    Alexandre, That's because, in my opinion, they try to make it too simple. They made it so simple that all they did was "handwaving". I sent my thoughts to RealClimate for confirmation and here is the email that I received from Gavin. Gavin's comment would have made my simple model more complex so I stayed with the simple model. Bob mostly right. You miss two key facts. First, all GHGs emit as well as absorb, and whether you will get warming or cooling in a region depends on the ratio of the change in absorption and the change in emittence. Second, the troposphere has many IR absorbers, the stratosphere only two (CO2 and O3 - everything else is minor). So the impact of CO2 above the tropopause is amplified. Otherwise you are spot on! Gavin > Hi, > > I've searched for an explanation of the reason that the Stratosphere cools > due to Global Warming and have not found a satisfactory answer. There > does seem to be quite a bit of hand waving though. > > I think that I now understand it but would like the confirmation of a > professional. If my understanding is correct, I would like to write a > blog on this most misunderstood subject. > > Please confirm if this is correct. > > Thank you, > > Robert Guercio > > The earth radiates Infrared Radiation in accordance with Black Body > theory. Most of the IR energy absorbed by CO2 has wave numbers of > approximately 650 and 1050. There is CO2 in both the troposphere and the > stratosphere so frequencies associated with these wave numbers emanating > from the heated earth heat up both the troposphere and the stratosphere. > Frequencies of all other wave numbers simply sail on through without > effecting either layer. > > If there is more CO2 in the troposphere, more of a chunk of the spectrum > is going to be taken out around these two wave numbers in heating up the > troposphere. Therefore, there is less energy in these two IR bands to heat > up the CO2 in the stratosphere and thus the stratosphere cools. >
  48. Stratospheric Cooling and Tropospheric Warming
    Tarcisio, I kept it ridiculously simple in order to explain a concept. I thought about bringing ozone into it which is also responsible for stratospheric cooling but for a different reason which is easy to understand. Incoming solar radiation interacts with the ozone causing the stratosphere to heat up. The ozone has thinned recently so less solar energy is reacting with ozone, thus cooling the stratosphere. However, by bringing ozone into the picture, it gets more complicated. Bob
  49. Stratospheric Cooling and Tropospheric Warming
    Ville, This could be the case if the temperature was at absolute zero where the spectrum is being measured and total saturation occurred. However, were that to happen, hypothetically of course, the temperature of the planet would increase allowing more IR energy to be in the atmospheric window. The area under that curve would still be the same or that of the energy of the incoming solar radiation. Just a minor point for precision. The graphs we are talking about represent energy but the y axis is actually power/meter squared wavenumber. Bob
  50. Stratospheric Cooling and Tropospheric Warming
    Thanks Bob, this is a brave attempt to explain a surprisingly complex subject. As I understood it, the post is coherent with the simplified version of the explanation that can be found in the NOAA Global Warming FAQ: An enhanced greenhouse effect is expected to cause cooling in higher parts of the atmosphere because the increased "blanketing" effect in the lower atmosphere holds in more heat, allowing less to reach the upper atmosphere. I've seen other competent guys try to explain the concept before, with limited success: Gavin Schmidt at RealClimate and Science of Doom.

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