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Comments 106001 to 106050:

106001. mistermack at 00:34 AM on 27 October 2010
        The 2nd law of thermodynamics and the greenhouse effect
        "Skeptics sometimes claim that the explanation for global warming contradicts the second law of thermodynamics." Do they? I've never ever read that till now. Seems like a great big straw-man to me.
        Moderator Response: Many of the posts appearing on the home page recently have been posted there to call attention to that same material having newly been created and added to the regular set of "Arguments." You can tell by reading to the end of the home page's post where you will see a green box which, in this case, states "This post is the Basic Version (written by Tony Wildish) of the skeptic argument 'The 2nd law of thermodynamics contradicts greenhouse theory'." Each of those regular Arguments begins with an orange box with a quote and link to a skeptic making that skeptic claim.
106002. Ken Lambert at 00:30 AM on 27 October 2010
        It's the sun
        Gentlemen Regarding the numbers I am currently crunching (Ref #651)- could anyone point me to some historical data on Wate Vapor + Ice Albedo feedback - currently quoted by Dr Trenberth at +2.1W/sq.m in AD2005. I could assume linearity back to zero in AD1750 but this is a very significant component, and this could widely affect the result of the Total forcing sum.
106003. KR at 00:27 AM on 27 October 2010
        Waste heat vs greenhouse warming
        Analogies and their issues; Analogies are fine when used to explain aspects of a complex system. They fail when you try to use them to disprove that complex system, because the analogy is not a 1-1 mapping. See a much more detailed posting here, motivated by similar logical issues earlier in this topic thread. I wouldn't bother to play the analogy game, CBD - that leads straight to this Bad Analogy error. If you want to disprove a theory or system, you have to do the work there, not in a made-up world whose parameters change with every reply.
106004. muoncounter at 00:27 AM on 27 October 2010
        Waste heat vs greenhouse warming
        #336: "that energy being injected into the environment is having no impact, (instead of warming things, it hightails for the stars)" All energy injected into the environment does not hightail for the stars ... some of it is trapped (or at least stored temporarily) here in an atmosphere increasingly rich in GHGs. Of course, those same GHGs also trap some of the far larger supply of energy from the sun. But bottom line, RSVP is a warmist!
106005. KR at 00:18 AM on 27 October 2010
        The 2nd law of thermodynamics and the greenhouse effect
        Berényi - I'll emphasize my primary point once more. To the extent (and this appears to be an interesting point of research) that MEP is a factor in climate dynamics, it's a factor not just in forcing deltas but in the state(s) prior to the forcing deltas. Therefore MEP is already part and parcel of the climate sensitivity to forcings. Not a new factor that will jump in, but an existing part of the system dynamics. That means that climate sensitivities to forcings still hold, that those measured 'black-box' sensitivities inherently factor in the MEP effects.
106006. muoncounter at 00:17 AM on 27 October 2010
        Measuring CO2 levels from the volcano at Mauna Loa
        #13: "Do Mauna Loa and other stations measure the concentration of other greenhouse gases in the atmosphere?" Yes, although not all sites around the world measure all species. Look at NOAA's data viewer where you can select among CO2, CO, CH4, O3, SO2, NOx, etc.
106007. Berényi Péter at 22:01 PM on 26 October 2010
        The 2nd law of thermodynamics and the greenhouse effect
        #66 e at 18:35 PM on 26 October, 2010 is it not possible that the rearranged landscape consists of a lowered local peak, rather than a translational shift of the landscape? It is certainly possible, but I don't see a compelling reason it should be so. Even for infinitesimally small increases of baseline opacity the transformation the landscape suffers seems to be of some more general form than simple downscaling. But I have not done a full mathematical analysis of the situation yet, it's just an impression. Do you have anything specific in mind? BTW, as I'm peeking into the literature, I see a widespread misconception about MEP-related role of radiative transfer in the climate system in general and about Dewar 2003 specifically. Stephen Mobbs is even enumerating in a presentation among Dewar's results the following proposition: "MaxEnt is equivalent to maximising the mean entropy production rate <σ> due to internal material processes – not including radiation [emphasis mine]" Journal of Physics A: Mathematical and General 2003, Volume 36, Number 3, 631 doi: 10.1088/0305-4470/36/3/303 Information theory explanation of the fluctuation theorem, maximum entropy production and self-organized criticality in non-equilibrium stationary states Roderick Dewar What Dewar actually says is this: "For climate systems there is an additional contribution to σ_Γ from radiative heating at planetary temperatures, deriving from the internal energy component of Q in equations (9) and (12). This contribution is not taken into account in the purely material entropy production of equation (15), and is in fact ignored in applications of MaxEP to the climate [16, 17]. Again Jaynes’ procedure provides the rationale for ignoring this contribution – radiative heating is reversible and does not contribute to the number of paths W(A^irr<λ>) in equation (24). To summarise, in applications of MaxEP to climate systems it is the irreversible, material entropy production that is maximised." It is said in the context of interpreting Paltridge's work on application of MEP on horizontal heat transport (advection) and he just tries to justify why radiation was ignored in that work. Indeed, as long as radiative heating is supposed to be reversible, it does not give a contribution to the number of paths. However, while it might have been a reasonable approximation for the specific problem Paltridge was interested in, it surely does not hold in general. In a semitransparent medium (like air) whenever radiative exchange occurs between two parcels at different temperatures, the process is irreversible and involves entropy production. It may be negligible at the center of CO₂ absorption band (at 15 μm) where mean free path of IR photons is small and nearby locations are at almost the same temperature, but as we move to the wings or even to an atmospheric window with no absorption lines at all just the H₂O continuum, parcels at vastly different temperatures can get into radiative contact (like hot (-50°C) Antarctic winter troposphere with cold (-80°C) surface). If one is interested in climatic effects or the radiative properties of CO₂, ignoring radiation entropy is certainly the most foolish track to take. As soon as we stop treating clouds, snow cover or ocean color (induced by biological processes, determining light extinction with depth) as boundary conditions, but include them as variables in the climate system, entropy production associated with ASR (Absorbed Shortwave Radiation) also enters the game.
106008. CBDunkerson at 20:23 PM on 26 October 2010
        Waste heat vs greenhouse warming
        RSVP, ok I'll play... now its a dam. So in the scenario you posit with the "narrow slot" the outflow of water is constrained... the inflow can increase without the outflow increasing in turn (until the water level rises so high that it overtops the dam). Please explain what mechanism you think exists which similarly constrains the outflow of energy from the Earth to a fixed amount. Also, decreasing the outflow by 100x is still going to cause the temperature to rise one hundred times faster than increasing the inflow by 1x. So we're still looking at AWH warming being an insignificant factor unless your unexplained mechanism for constraining radiation outflow is itself somehow immune from being blocked by greenhouse gases. So there you go. Your analogy can work. You just have to explain two little things which violate the laws of physics as we know them.
106009. e at 18:35 PM on 26 October 2010
        The 2nd law of thermodynamics and the greenhouse effect
        BP >If there is a maximum entropy production principle at work indeed, for a neutral feedback you need the same climate state to be found right at a peak on the rearranged landscape, which is extremely unlikely. Correct me if I'm missing something here: is it not possible that the rearranged landscape consists of a lowered local peak, rather than a translational shift of the landscape? In such a case, we would expect a neutral response since we would already be at the local peak. If so, is it not invalid to assume that neutral feedback is "extremely unlikely?"
106010. RSVP at 18:29 PM on 26 October 2010
        Waste heat vs greenhouse warming
        CBDunkerson #340 You are correct about a lake with the topology you assume. In mine, the outflow is restricted through a narrow slot, and likely isnt too common in nature, but is possible. I should have said "dam", my bad. But now that you have taken up the point, it looks like there are two things to consider as far as the comparison with global warming. In the lake or dam, the rate of level change will depend on three things. How much water this new "spring" represents, the uptake capacity, and to what extent the outflow will increase as a result of an increase in height. This increase must be less than the source influx. This last factor seems to be key, and unless this is determined, I dont see how anyone can claim to be in a position of certainty. The question is really not whether it is accumulating. The question is how fast. All I am hearing is that radiation increases as the fourth power of temperature. If things were that simple, you wouldnt have to increase the size of an audio amp's cooling fins as a function of power rating. In the same way, the Earth's thermal radiation capacity is limited by the size of the Earth and any and all properties that affect its total emissivity. e #337 What I explain above applies in the same way to what you bring up here. You seem to have ignored the words "in a way that exactly compensated...", which implies a difference that accounts for energy that is "temporarily" being stored. And "temporary" really means "permanant" as long as the additional flux is present.
106011. Berényi Péter at 16:54 PM on 26 October 2010
        The 2nd law of thermodynamics and the greenhouse effect
        #63 KR at 13:28 PM on 26 October, 2010 Currently we are moving towards (but have not reached) an equilibrium - but a 'steady-state' system will still reach an entropy balance (dynamic equilibrium) where energies do not change I think you still don't get it. Here is a readable account on MEP (Maximum Entropy Production), SOC (Self-Organized Criticality), including toy models like Sandpile Avalanche Dynamics and FT (the Fluctuation Theorem). Non-equilibrium Thermodynamics and the Production of Entropy Understanding Complex Systems, 2005, 2005, 41-55 DOI: 10.1007/11672906_4 4 Maximum Entropy Production and Non-equilibrium Statistical Mechanics Roderick C. Dewar Critical systems' scaling behavior is well understood in physics. If the majority of climate scientists think climate is somehow different with a very special structure that invalidates general principles, they have to explicate this idea clearly, simple hand waving like in Ozawa 2003 would not suffice.
106012. Kooiti Masuda at 16:21 PM on 26 October 2010
        The 2nd law of thermodynamics and the greenhouse effect
        Concerning thermodynamics, we have several different levels of knowledge. 1. Equilibrium thermodynamics. We can compare two states of thermodynamic equilbrium of the same system, and tell in which direction spontaneous changes can occur. But this formulation cannot usually describe the processes of the changes which are non-equilibrium. 2. Local thermodynamic equilbrium. While the climate system as a whole is clearly not in a thermodynamic equilibrium, we can define thermondynamic quantities such as temperature in a certain spatial and temporal scale, which is much larger than individual molecules and individual collisions between molecules, but much smaller than the whole atmosphere. If we smooth out the microscopic variabilities, the thermodynamic quantities can be considered as functions of macroscopic space and time coordinates. (This condition does not hold in the upper atmosphere, but acceptable for the troposphere and the stratosphere.) 3. Formulation of non-equilibrium thermodynamics. We can describe the rate of change of entropy in the climate system or a certain subsytem of it as the sum of entropy exchange and entropy production. Entropy production must be positive. There is no other formal constraint at this level. 4. Dynamic steady states in the entropy balance. The climate system can be approximated as a steady-state system which exports as much entropy as is produced within it. The system may actually fluctuate around the steady state. If the external condition changes slowly, the state of the system will drift acoordingly, but it may still be be approximated as a steady state. If the external condition changes too fast, the state cannot be considered as steady. 5. The hypothesis of maximum entropy producition. Under a certain external condition, there is a range of approximately steady states which our system can take. Among them, the state which has the maximum rate (=quantity per unit time) of entropy production is likely to be realized. I think that the items 1 and 2 are shared by effectively all physical climate scientists, and that 3 and 4 are acceptable by the majority of them (though many of them do not conceive them by themselves), but that 5 is held just by a minority among them.
106013. Daniel Bailey at 14:01 PM on 26 October 2010
        Measuring CO2 levels from the volcano at Mauna Loa
        Re: Agnostic (13) Whenever I have a question (and having an enquiring kinda mind, I have many [questions, not minds; multiple minds would be silly, wouldn't it? Shut up and let the man talk!]), I like to go straight to the source. In this case, the Earth System Research Laboratory that operates the Mauna Loa facility in question. There one would thus find a full panoply of measurements of various and sundry greenhouse gases in full regalia. But that's me. As far as your last question, given your earlier worthy comment on that subject, that would seem to be a rhetorical question. But yes, that would be the reaction of sensible people. Which is why our politicos in America will procrastinate until it's too late. Prevention is out the window. All we will be able to do is to adapt as best able. Asbestos underwear, anyone? The Yooper
106014. Albatross at 13:59 PM on 26 October 2010
        Irregular Climate podcast 13
        I really enjoyed listening to this today whilst doing some number crunching Excellent (and comprehensive) job guys.
106015. Jerry at 13:39 PM on 26 October 2010
        Measuring CO2 levels from the volcano at Mauna Loa
        I don't think the sea breeze has much of an effect on Mauna Loa. What does have a big effect is the inversion layer. From their website "MLO also protrudes through the strong marine temperature inversion layer present in the region. This inversion layer acts like a lid and keeps the lower local pollutants below the observatory." I am not an expert but I do live in the area. Often the lower level winds and the winds aloft are blowing different directions, which can make for interesting cloud watching. Jerry
106016. KR at 13:28 PM on 26 October 2010
        The 2nd law of thermodynamics and the greenhouse effect
        Berényi - I would actually have to disagree about equilibrium states. If a constant input and sink of energy are maintained (sun and the 3 degree K of space), the climate will cycle around equilibrium based on the internal variance of weather. Currently we are moving towards (but have not reached) an equilibrium - but a 'steady-state' system will still reach an entropy balance (dynamic equilibrium) where energies do not change. As Riccardo stated, the MEP indicates the path taken towards equilibrium, or as I understand it entropic balance. That affects the speed of attaining equilibrium, not the final thermodynamic state. Re-reading Ozawa et al: they are indeed speaking of speed (delta) of entropy, not the final thermodynamic states. If you disagree, please point out the sections of the paper that indicate this. You have also not addressed my point here, that high entropy production if correct is already part of the climate sensitivity - it's already incorporated into our knowledge and models of climate behavior.
106017. Riduna at 11:08 AM on 26 October 2010
        Measuring CO2 levels from the volcano at Mauna Loa
        Mauna Loa and other sampling sites provide an interesting record of increasing atmospheric CO2 but how much of it is the result of human activity (and how is that determined) and how much is from other sources? Global warming arises from the increased presence of greenhouse gases (CO2-e) in the atmosphere, CO2 being only of them. Do Mauna Loa and other stations measure the concentration of other greenhouse gases in the atmosphere? Measuring CO2 concentration only provides part of the picture. For example, as global temperatures rise melting permafrost and ice, methane is released from subsurface decaying material. When ocean water warms it is less able to absorb atmospheric CO2 and increases its release of that gas into the atmosphere. Are these effects identifiable and are they measured? When we talk of the importance of keeping the concentration of CO2 in the atmosphere to less than 450 ppm, should we not be stressing the importance of keeping the concentration of CO2-e in the atmosphere to less than 450 ppm?
        Moderator Response: Your questions are generally addressed in the following posts:
        How do human CO2 emissions compare to natural CO2 emissions?
        Water vapor is the most powerful greenhouse gas
        What is methane's contribution to global warming?
106018. Berényi Péter at 10:33 AM on 26 October 2010
        The 2nd law of thermodynamics and the greenhouse effect
        #59 KR at 07:53 AM on 26 October, 2010 If Riccardo is correct, this means that the MEP principle you brought up has zero effect on the equilibrium temperature change for various forcings, only (if the MEP hypothesis is true) upon the speed (time lags) at which the climate moves there Wait, I can see a conceptual confusion here. The climate system is never in thermodynamic equilibrium, not even close to one and the MEP tells nothing about the path to be taken there either. It's in a steady state, which is a completely different thing altogether. In this state a pretty stable stream of energy flows through it, arriving as low entropy sunlight and (part of it) leaving as high entropy thermal IR radiation against the cosmic microwave background. So there is also a constant rate of entropy production. In fact it is not really constant, just a target value actual entropy production tends to fluctuate around in a scale invariant manner. It is much like sandpile avalanche dynamics in this respect. If you change the system by increasing baseline IR opacity of the atmosphere a bit, I have already shown you it decreases entropy production rate (along with increasing average surface temperature) if all else is held unchanged. You can depict it as a landscape defined over a phase space of climate states by the entropy production rate function. MEP means the climate state tends to linger around a peak. As soon as baseline IR opacity is increased by a small quantity, the landscape gets rearranged somewhat. If there is a maximum entropy production principle at work indeed, for a neutral feedback you need the same climate state to be found right at a peak on the rearranged landscape, which is extremely unlikely. All other positions would involve some negative feedback and there is no room for a positive one at all. Of course the MEP is only a local constraint, meaning all sufficiently small changes of the climate state relative to the actual one tend to decrease entropy production rate. It does not mean there are no higher peaks at all along the landscape, accessible only through deep valleys (that is, not accessible under normal circumstances). With an ever increasing baseline opacity of the atmosphere at some point the topological structure of attractors over this landscape may get rearranged (at which point, we have no idea), so as a previously inaccessible peak becomes accessible along a continuous path with an ever increasing entropy production rate (or at least it only needs to jump through shallow valleys). If this happens, a climate regime shift occurs, but it is a highly nonlinear process, inexpressible in the climate sensitivity formalism. It is not clear either if this new steady state would imply higher or lower average surface temperatures (or the same ones with some regional rearrangement). Unfortunately mainstream climate science failed to ask these questions so far, so for the time being we do not have a chance to get proper answers.
106019. Riccardo at 09:07 AM on 26 October 2010
        The 2nd law of thermodynamics and the greenhouse effect
        KR very much like the equilibrium state, i.e. that of maximum entropy, in statistical thermodynamics can be defined as the most probable state, the maximization of the entropy production rate may be thought as defining the most probable path toward equilibrium. I'm not an expert on non-equilibrium thermodynamics and I can't tell if the MEP path is always the fastest possible. In simple systems I guess it probably is, it's not obvious it will be so in general.
106020. Harald Korneliussen at 08:41 AM on 26 October 2010
        Irregular Climate podcast 13
        Typo: Micheal => Michael
        Response: Fixed, thanks
        
106021. CBDunkerson at 08:14 AM on 26 October 2010
        Waste heat vs greenhouse warming
        RSVP, back at 272 you wrote: "Imagine a lake whose level is seen to rise 3 inches in the course of 150 years due to a new spring breaking ground up stream." I couldn't "imagine" this because even the analogy breaks the laws of physics. So let's see if fixing it helps you see what we are saying. If a lake (i.e. the Earth's atmosphere) suddenly acquired a new source of incoming water (i.e. heat), such as the spring in your example (i.e. waste heat), it would NOT slowly increase in depth (i.e. temperature) over 150 years. The depth would increase almost immediately and then stop because the higher water level would allow more water to flow OUT of the lake as well. Once the new net outflow was equal to the new net inflow the new water level of the lake would then be set. How long the spring continues pouring in water is irrelevant... it doesn't lead to an ever increasing water level because when the inflow increases the outflow inherently must as well. Further, if the new inflow ever stopped or declined (i.e. we began producing less waste heat) the lake would quickly drop down to a lower level... the constant inflow is required just to MAINTAIN a small increase in the water level rather than producing a continually increasing level. Now, if you were to put sand bags blocking some of the streams leading out from the lake (i.e. decrease radiation outflow by increasing greenhouse gases) the lake would rise until the net outflow from the remaining streams, or possibly over the tops of the sandbags, again equaled the net inflow. The water level would then stay at that new height until the sandbags were removed. The inflow and outflow of water in a lake and energy in the atmosphere are pretty close corollaries... so long as you stick to actual physics for both.
106022. scaddenp at 07:54 AM on 26 October 2010
        Blaming global warming on the oceans - a basic rebuttal
        Dan, since oceans cant generate heat, then heat from oceans cant be forcing only a mechanism. So the correct approach is do what you do, but plug in the real forcings instead. Already done of course, looks within Benestad & Schmidt
106023. KR at 07:53 AM on 26 October 2010
        The 2nd law of thermodynamics and the greenhouse effect
        * state *
106024. KR at 07:53 AM on 26 October 2010
        The 2nd law of thermodynamics and the greenhouse effect
        Riccardo - So, the MEP principle doesn't affect the thermodynamic end stateto, but simply says that systems will tend to move to that state as quickly as possible? Berényi - If Riccardo is correct, this means that the MEP principle you brought up has zero effect on the equilibrium temperature change for various forcings, only (if the MEP hypothesis is true) upon the speed (time lags) at which the climate moves there.
106025. Riccardo at 07:27 AM on 26 October 2010
        The 2nd law of thermodynamics and the greenhouse effect
        nealjking and indeed you can't. First, the MEP principle says other things than the 2nd law; it says that a system out of equilibrium will follow the path that maximises the entropy production rate. Note that it does not define the final equilibrium state, which (apart from metastable states which might occur) is still given by standard thermodynamics; it just tell us the path toward it. Second, it aspires to be a principle and hence it's not demonstrated; only time will tell if it really is a general principle or if it has a limited range of validity. It is a very interesting topic, whose consequences are yet to be unveiled. Unfortunately, it currently does not add much to our knowledge of the final fate of our planet, so neatly given by standard thermodynamics.
106026. RSVP at 07:06 AM on 26 October 2010
        Waste heat vs greenhouse warming
        Bibliovermis #335 "... a well-established field of scientific endeavor is composed of grossly incompetent, corrupt individuals" This is a good point, and we would all be better off assuming good will on all sides.
106027. Daniel Bailey at 07:05 AM on 26 October 2010
        Why is Greenland's ice loss accelerating?
        Stop the presses, this just in:

        Danish research scientist Sebastian Mernild of Los Alamos National Laboratory in the US told national daily newspaper Jyllands-Posten that his calculations show that 540 cubic kilometres of inland ice, weighing approx. 500 gigatons, have melted this summer, which is 25-50% more than in a typical year.

        According to Jyllands-Posten, climate researcher Jason E. Box from Byrd Polar Research Center at Ohio State University, USA, is also saying that the inland ice melting has been particular strong this year:

        "It is my assessment that we have had the strongest melting since they started measuring the temperature in Greenland in 1873."

        Let the good times roll. The Yooper
106028. KR at 06:59 AM on 26 October 2010
        Waste heat vs greenhouse warming
        RSVP - If you disagree with the level of CO2 forcings, I would suggest taking it to the How do we know more CO2 is causing warming thread; that's where it's appropriate. The value of 2.9 W/m^2 is quite well established from physical theory, from multiple orbital and ground measurements, etc.
106029. GFW at 06:48 AM on 26 October 2010
        Measuring CO2 levels from the volcano at Mauna Loa
        For those wondering about how the offshore breeze results in higher air descending to the mountaintop, it's just fluid continuity. If air at or below the mountaintop is flowing outward, something has to replace it ... which means air from higher up. While air is not a "perfect fluid", divergence still has to be pretty darn close to zero :-)
106030. e at 06:45 AM on 26 October 2010
        Waste heat vs greenhouse warming
        RSVP > if the atmosphere were to always radiate more and more in a way that exactly compensated any positive changes in heat, global warming wouldnt be possible Seriously, I am perfectly aware that "Radiated energy increases as the 4th power of temperature" These two sentences are in direct contradiction to one another, and reflects your inability to accurately visualize the simple logic of how this would play out. If there is a positive change in the rate of heat input, then temperature will increase. If temperature increases, then radiated energy increases. As long as the output radiation is less than the input energy, then temperature will continue to increase, and just as you claim to be aware of, so will radiated energy. If temperature continues to increase, then output radiation will continue to increase, and if it does, it is mathematically and logically inevitable that eventually output will increase to a point where it matches input, at which point temperature increases will stop. If temperature increases stop, then so will changes in output, and since this is precisely the point where input matches output, there will be no more changes to the total energy content of the system. The overall temperature has gone up, but past this point there is no more accumulation.
106031. nealjking at 06:41 AM on 26 October 2010
        The 2nd law of thermodynamics and the greenhouse effect
        #54, Berényi; #55, Riccardo: Looking briefly at Ozawa, I notice again and again the phrases: "the hypothesis of MEP," "that might be applicable." Why would I want to construct an understanding of the 2nd law on the basis of something that looks rather speculative?
106032. KR at 06:39 AM on 26 October 2010
        The 2nd law of thermodynamics and the greenhouse effect
        Berényi - Thunderstorms and hurricanes are excellent examples of increasing local entropy, not decreasing it as you claim, they reduce order. A small turbulent variation in updrafts can trigger a thunderstorm, tipping a temporarily ordered system downslope. Pre-storm states are more ordered, with warm wet air present - a thunderstorm lifts and condenses approximately 5×10^8 kg of water vapor. Hurricanes do much more. The result is higher entropy, more disorder, less concentration of energy. What you have argued is that large scale fractal patterns of water vapor, or cloud formations of some kind, would form as part of local variation within the degrees of freedom of the climate system. Large scale patterns of water vapor (big enough to change the climate, certainly) would require long term persistent order to exist. That's a widespread, persistent low entropy system, and you have presented no evidence for such to exist. Your example of thunderstorms and hurricanes does not support your theory; quite the contrary. More to the point: Ozawa et al 2003, as Riccardo points out, indicates that "turbulent fluid systems adjust themselves to the states of maximum entropy production". Assuming that this is so (and it seems a reasonable hypothesis), the climate system is already adjusted to the state of maximum entropy production. Your hypothesis that the climate will adjust to increase entropy and avoid warming fails to consider this - that it's already adjusted in that fashion, and that this max entropy production is part of the existing climate and climate feedbacks. Maximum entropy production won't suddenly switch on in response to climate forcings - it's already there, already part of the system, already part of the climate sensitivity. It certainly won't kick in abruptly to save us from greenhouse gas heating.
106033. RSVP at 06:29 AM on 26 October 2010
        Waste heat vs greenhouse warming
        KR #333 "Anthropogenic heat flux = 15 TW/year" You mean 15 TW all year. Day and night. As there are 60 x 60 x 24 x 365.25 = 31536000 seconds in a year, that gives you 31536000 x 15 x 10E12 = 473040000 x 10E12 or 473 x 10E18 Joules. The heat flux value you cite for CO2 is an estimate, not a measurement; derived by correlating the observed warming with the observed CO2 increase and contrasting this with the known total solar heat flux. But the situation would be completely inverted, IF you started with the opposite assumption. So the only way you could be right about this is if you can prove that all that energy being injected into the environment is having no impact, (instead of warming things, it hightails for the stars). This is hard to believe as glaciers and polar caps melt before us.
106034. Riccardo at 06:17 AM on 26 October 2010
        The 2nd law of thermodynamics and the greenhouse effect
        nealjking "I am not an expert on non-equilibrium thermodynamics." you're in good company, I don't think you'll find many experts on non-equilibrium thermodynamics around, let alone on the MEP principle. As with the 2nd law of thermodynamics (just a reminder, it's the topic of this post) you'll find, instead, a lot of misuses. Apart from Miskolczki "theory", there's really no contraddiction between an increased GHG effect and the MEP principle. A carefull look at section 3 in Ozawa et al. 2003, and fig. 5 in particular, should make it clear.
106035. Berényi Péter at 06:05 AM on 26 October 2010
        The 2nd law of thermodynamics and the greenhouse effect
        #52 KR at 02:56 AM on 26 October, 2010 Local effects (more ordered cloud formations, less uniform water vapor distributions, etc., that you have suggested in the past) that are not locally high entropy will not occur What you are effectively saying is hurricanes, supercells or tornadoes (with their more ordered cloud formations, less uniform water vapor distributions, etc.) are impossible. I don't think you mean it. Although the moderator was kind enough to delete it once, I give it another try. MEP is nothing fancy, really. The underlying principle is the same as for water flowing downhill; it simply follows the steepest gradient available. Note it says a bit more than the 2nd law, which only states water would not flow spontaneously uphill. In systems like this local entropy fails to win out, somehow. Think about it.
106036. robert way at 06:00 AM on 26 October 2010
        Do critics of the hockey stick realise what they're arguing for?
        Protestant, "We already have evidence on 60 year cycles like PDO and AMO after all, which are caused by winds, which are caused by pressure changes in condensation (cloud formation, models ignore this)" The AMO is not caused by this process at all. You should consider reading the literature prior to making grand statements that are vitally flawed. The AMO is a proxy for the strength of the thermohaline circulation (THC). Positive phases indicate a strengthening of the THC and negative phases indicate a weakening of the THC. It occurs over a roughly 70 to 80 year period and is directly linked to sea ice transport through the fram strait. I can give you a more direct explanation if you prefer? Another side note, Judith Curry may be well-known but I would rather get my information from other people than her. There's a reason she's taken such a beating at RC and elsewhere, it is because she is often wrong. Finally, I do agree with one thing you had to say, this post does insinuate that there is a clear forcing and effect. I believe that millennial scale climatic changes are inherent within the climatic system as found by Viau et al (2006) however I don't think they have a cloud origin. I would guess ocean driven with some sort of Solar initiation perhaps.
106037. nealjking at 04:00 AM on 26 October 2010
        The 2nd law of thermodynamics and the greenhouse effect
        Berényi: I am not an expert on non-equilibrium thermodynamics. My main exposure to this MEP claim has been through Miskolczki's claim that the MEP ruled out any possibility of the enhanced greenhouse effect at all. I spent some time trying to find out what this meant, but it eventually became clear enough to me that Miskolczki was also not an expert in non-equilibrium thermodynamics, and was using this principle, that he did not fully understand, to counter well-known physics that everybody understands. This seems to me not to be the most prudent way to arrive at an understanding of phenomena. Usually, one is better advised to try to extend one's understanding from things well known to things less known.
106038. Andy Skuce at 03:17 AM on 26 October 2010
        Measuring CO2 levels from the volcano at Mauna Loa
        Thanks for the comments. I replaced "offshore breezes" with different wording that I hope will be unambiguous. I also reworded the latter part of that sentence to make it more clear that at night the observatory samples well-mixed high altitude air from the Central Pacific rather than the lower altitude air that has come upslope from the lower reaches of the island and which may be slightly depleted in CO2 due to the effects of the vegetation there. Some of this will be discussed in more detail in a forthcoming Advanced Version of this rebuttal.
106039. Bibliovermis at 03:01 AM on 26 October 2010
        Waste heat vs greenhouse warming
        Why should we be happy about explaining, and re-explaining & then explaining yet again, basic, fundamental physical properties to somebody who adamantly insists that these misconceptions are the reason why a well-established field of scientific endeavor is composed of grossly incompetent, corrupt individuals? Yes, the scientific theory of anthropogenic warming can be disproven. Your lack of understanding and refusal to learn is not sufficient. We have been magnimous, but you are wrong - plain and simple. Your conceptions of how heat moves through the atmosphere are indeed utter nonsense. Indignation & insults (e.g. "you're just insecure") do not impart validity. Repeating the same misconception over & over & over is a good way to get people to snap at you. Global warming is how more & more energy is radiated from the planet. No additional energy can leave the system until there is an increase in temperature. The temperature cannot rise without more energy leaving the system. Energy can only leave the system through radiation; convection only moves it around internally. Energy cannot simultaneously cause a temperature increase & remain in the system (i.e. accumulate).
106040. KR at 02:56 AM on 26 October 2010
        The 2nd law of thermodynamics and the greenhouse effect
        Berényi - Are you arguing that the climate will (by virtue of many degrees of freedom) increase entropy production in some fashion in order to avoid raising temperatures? Do you have any evidence for such an assertion? Note that if a system could reach a more entropic state by reordering internal components/relationships, but those internal elements would require a less entropic (more ordered) state, local entropy will win out and the system entropy will be the product of the local (internal) entropies. Local effects (more ordered cloud formations, less uniform water vapor distributions, etc., that you have suggested in the past) that are not locally high entropy will not occur. In short, the system is the product of the components, not the other way around. And quite frankly a warmer planet with a higher effective photosphere for portions of the emission spectra is the most entropic solution - at least, according to and supported by the data.
106041. Albatross at 02:43 AM on 26 October 2010
        DMI and GISS Arctic Temperatures: Hide the Increase?
        Peter @129 and 133, Thanks for this Peter-- I realise that it is easy for me and others to talk hypotheticals, but another story entirely to actually track down the data, undertake the analysis and then write it up. Great work. Peter "My summary based on the best available evidence is that Summer Arctic temperatures are increasing slightly, the Lansner chart contains errors and any conclusions based on this chart are likely to be incorrect. Based on your findings and those of Screen and Simmonds (2010) I concur with that assessment. "I have concluded that "pixel counting" is not an appropriate method for analysing trends or data in this case. The Lansner chart has large differences from the correct DMI values and it appears the conversion of numerical data to images and then pixel counting from these images is easily capable of creating bad data." FWIW, I would concur with that assessment as well. It seems that the alleged "cooling" is an artifact of a combination of issues with the DMI data and Lansner's methodology and/or analysis. I would also like to second what Doug wrote @133. It may be worth bringing this to the attention of DMI as well...the poor match that you show between ERA-interim and DMI (for the melt season) is rather troubling. Just one example in addition to the "step" issues, something odd seems to have happened with the DMI data between 1991 and 1995.
106042. CBDunkerson at 02:43 AM on 26 October 2010
        Waste heat vs greenhouse warming
        muoncounter #331: "In order for your argument at 317 to work at all, you must accept the points (its warming, its not the sun, etc) made in 325." I dunno. I've yet to meet a dedicated 'skeptic' who isn't capable of passionately believing three or more contradictory things at the same time.
106043. Daniel Bailey at 02:22 AM on 26 October 2010
        Measuring CO2 levels from the volcano at Mauna Loa
        Re: chrisd3 (8) As a former nautical cartographer, I didn't realize that it wasn't common knowledge about such breezes. You and Kevin McKinney should share sailing backgrounds sometime.
106044. michael sweet at 02:07 AM on 26 October 2010
        Blaming global warming on the oceans - a basic rebuttal
        Dan, The issue that I have with your argument is that sea surface temperature is determined by the interaction of the atmosphere and the ocean. Your proposal suggests that global warming is caused by the ocean heating the atmospehre. What heats the ocean? Since both the ocean and the atmosphere are warming the heat has to come from somewhere. CO2 heats the atmosphere. The heated atmosphere heats the ocean. The energy to heat both comes from the sun. Your equation works because the ocean is heated by the atmosphere. Since the two are linked you observe this link with your calculation.
106045. KR at 02:07 AM on 26 October 2010
        Waste heat vs greenhouse warming
        RSVP - No, not insecure, just tired of the same disproven skeptic arguments being brought up again and again.. oh look, and again. Increased thermal radiation affects the contributions of anthropogenic heat flux, and it affects the contributions of greenhouse gases. The same rules apply in all cases. Energy changes lead to temperature changes, and thence to radiation changes that tend to balance out the energy change. The 4th power of temperature relationship with energy is the negative feedback that limits temperature changes. However, GHG's are two orders of magnitude larger, and hence have a much larger effect. I'm quite frankly puzzled as to why you continue to think that AHF dominates global warming. Anthropogenic heat flux = 15 TW/year Greenhouse Gas entrapment = ~1550 TW/year Now, which of these will dominate climate effects?
106046. RSVP at 01:48 AM on 26 October 2010
        Waste heat vs greenhouse warming
        KR #330 When you snap "incorrect" and "utter nonsense", it makes you appear insecure. If I am the one thats all messed up, you could be a little more magnanamous. I may be completely wrong, and if so, at least in being wrong, it would be just that much more proof that AGW is a good theory. You should be happy to proove me wrong, not upset. Besides, I am not sure what you have to worry about? There is still 20,000 experts out there that have signed on who would have to be convinced. AGW is an entrenched theory with a lot of backers. One might ask if it is even possible to disprove at this point, assuming it were completely flawed. Seriously, I am perfectly aware that "Radiated energy increases as the 4th power of temperature". What I find strange is how increased thermal radiation is used to undermine the contribution of waste heat, while the basis of GHG heating depends on jsut the opposite. Conclusion. Calm down, be happy. Besides, as far as every reading this, you are winning, (and won before the discussion even began given the rule set).
106047. Riccardo at 01:46 AM on 26 October 2010
        Measuring CO2 levels from the volcano at Mauna Loa
        chrisd3, the Mauna Loa Observatory is already high enough to be a good place to measure background CO2 concentration, unless air coming from lower elevations "contaminate" the readings. At night, or whenever there's no upslope wind, there's no reason for concern. Whether the air comes from higher up (which is often true) or from the same level is irrelevant.
106048. nealjking at 01:39 AM on 26 October 2010
        The 2nd law of thermodynamics and the greenhouse effect
        #48, Berényi Péter; #49, Kooiti Masuda: TonyWildish is not talking about the emissivity of the gas, but the "effective emissivity" of the Earth. So the whole discussion about Kirchoff's law, etc., has nothing to do with what he's talking about. He's just saying that the Earth will "have a harder time" tossing off radiation at a specific frequency if the absorption coefficient of the atmosphere at that frequency increases. "Emittance is proportional to the product of emissivity (a dimensionless number) and the fourth power of absolute temperature." This is not quite true: the T^4 law relates to the total power integrated over all frequencies, in a case when there is no frequency-specific filtering (like absorption lines): this doesn't apply to cool gases, which have line spectra. In these situations, what is more relevant is the Planck distribution, which is multiplied with the absorption spectrum to get the emission spectrum. Maximum entropy production: I am not very familiar with this "principle," and have no clear reason to believe in it. The only other time I've heard of anyone trying to apply it to atmospheric processes was when Miskolczi was trying to disprove the possibility of the greenhouse effect. I didn't believe it then, and I have no reason to believe it now.
106049. muoncounter at 01:27 AM on 26 October 2010
        Waste heat vs greenhouse warming
        #326: "Not sure why you say this?" In order for your argument at 317 to work at all, you must accept the points (its warming, its not the sun, etc) made in 325. Like it or not, you're an AGW guy now. "There is no waste heat sunset." Nor is there a waste heat correlation. Your calculation says all energy consumed directly warms the atmosphere; temperature anomalies should correspond with historic energy consumption (see EIA energy consumption tables). You picked one year's energy consumption; over the longer term, how well do temperature anomalies track energy use? Your model makes a testable prediction. In order for your model to be taken seriously (although most others here have already said it should not), it still must be checked against observations. Sunrise, sunset.
106050. Berényi Péter at 01:20 AM on 26 October 2010
        The 2nd law of thermodynamics and the greenhouse effect
        #49 Kooiti Masuda at 22:42 PM on 25 October, 2010 For entropy production in the climate system, see Ozawa (2003) (Unfortunately I do not find a free copy) Dear prof Masuda, here is a copy of the paper you are referring to. Reviews of Geophysics, 41, 4 / 1018 2003 doi:10.1029/2002RG000113 THE SECOND LAW OF THERMODYNAMICS AND THE GLOBAL CLIMATE SYSTEM: A REVIEW OF THE MAXIMUM ENTROPY PRODUCTION PRINCIPLE Hisashi Ozawa, Atsumu Ohmura, Ralph D. Lorenz & Toni Pujol Unfortunately their claim "On the contrary, absorption of radiation is essentially a linear process; its rate is given by the flux of radiation multiplied by the absorptivity of the material under consideration. There can be no feedback mechanism for the strength of the flux or the absorptivity in this process. Radiation can therefore be seen to be just an energy source for the climate system." is not a valid one, as absorption of radiation clearly depends on things like clouds, snow cover, foliage and airborne dust. Looks like there can be feedback mechanisms after all, as distribution of many absorbers are determined by climate. Their omission of the factor 4/3 from the standard expression of radiation entropy is strange. Also, total entropy production is the difference between entropy of outgoing (reflected/dispersed short wave and emitted thermal) radiation and that of incoming sunlight. The MEP, being a pretty universal principle covering all steady state open thermodynamic systems with sufficient degrees of freedom, should not differentiate between internal modes of energy transfer in a way they claim.

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