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Comments 62701 to 62750:

62701. dana1981 at 08:01 AM on 3 March 2012
       Wall Street Journal 'Skeptics' Misrepresent the IPCC
       Mammal_E - indeed, all the denialists get out of any model prediction or projection is "the model is wrong." This includes "skeptics" like John Christy, coincidentally. They never seem interested in examining why the model projections were "wrong", which is usually either because the model sensitivity was high (as in Hansen 1988) and/or because the emissions scenarios were not perfect.
62702. dana1981 at 07:57 AM on 3 March 2012
       Wall Street Journal 'Skeptics' Misrepresent the IPCC
       Todd F - no, the FAR did not account for aerosols. See the link provided by mdenison in comment #1 for details. As that post discusses, accounting for aerosols would reduce the net forcing, which would thus suggest the actual climate sensitivity is somewhat larger than 2.5°C for 2xCO2 (as sensitivity = dT/dF).
62703. Mammal_E at 07:50 AM on 3 March 2012
       Wall Street Journal 'Skeptics' Misrepresent the IPCC
       "Skeptics" sometimes jump on this sort of thing as equivalent to cherry picking, in that you've fed the observed (known in hindsight) values of model inputs into the original model to yield new predictions or select which predictions to consider. However, this exercise actually confirms the validity of the conceptual understanding that the model embodies, because the structure of a model and the particular values of its inputs are completely separate things. Consider: I my conceptual understanding of accounting is embodied by this model of the growth rate of my bank account: rate of balance increase = salary - expenses + interest - fees Based on this model, I predict that if my salary increases by $100 per month and everything else stays the same, my bank account balance will increase by $100 per month. (Note: this prediction is not the same as saying that my bank account is ONLY affected by salary and not at all by interest, fees, or expenses). Now, suppose that my salary actually increased by $80 per month and the bank added a new fee of $10 per month, so that my bank account only grows by $70 per month. Does this discrepancy between predicted and realized rates of increase invalidate the model, or my conceptual understanding of the system? NO! The only thing it indicates is that predictions about future changes in model input values were not quite right right. The conceptual understanding is intact, because when I use the observed input values, the model accurately predicts the observed change in the state variable.
62704. ribwoods at 07:10 AM on 3 March 2012
       Greenhouse Effect Basics: Warm Earth, Cold Atmosphere
       (continuing my preceding comment) The most logical correction is probably to interchange "escaping to space" and "entering the system" wherever they appear. This reversal doesn't seem to have affected any subsequent argument. skept.fr @38 seems not to have noticed, and writes as though your statement in #36 were corrected to the proper sense.
62705. Todd F at 07:07 AM on 3 March 2012
       Wall Street Journal 'Skeptics' Misrepresent the IPCC
       Good post. Is there any indication that FAR took account of aerosols? I see from your source where the actual forcing was +0.63W/m^2, but the source doesn't include the impact of aerosols. NASA has its estimates in below link. The 1990-2010 impact of aerosols (tropospheric+stratospheric+Black Carbon+Aerosol indirect effect), is -0.38 W/m^2 for 1990-2010, which offsets their estimate of GHGs, which they calculated at +0.71 W/m^2. That nets out to +0.33 W/m^2. Could also add in snow albedo at +0.05 W/m^2 and solar at -0.12 W/m^2. Given that, one might expect even less warming than you calculated assuming +0.63W/m^2. http://data.giss.nasa.gov/modelforce/RadF.txt
62706. ribwoods at 06:50 AM on 3 March 2012
       Greenhouse Effect Basics: Warm Earth, Cold Atmosphere
       Tom Curtis @36: "The most fundamental fact about the greenhouse effect is that if the energy escaping to space exceeds the energy entering the system, then the temperature will rise until they balance again. If the energy escaping is less than the energy entering system, temperatures will fall until they balance again." Don't you have the two cases backwards there? If energy escaping exceeds energy entering, the temperature will fall, not rise.
62707. Chris G at 05:40 AM on 3 March 2012
       Wall Street Journal 'Skeptics' Misrepresent the IPCC
       The take-away that I took from that RC thread was that Anteros is trying to assert that the IPCC did not know what they were talking in 1990 about because they were not able predict the future GHG emissions with high accuracy.
62708. Michele at 05:39 AM on 3 March 2012
       Radiative Balance, Feedback, and Runaway Warming
       @ Jose_X #68 I try to give some answers. 1) Atmosphere 100%N2 The atmosphere is perfectly transparent and so isothermal: that’s, Ts = Tt = Tef where ‘s’ is surface, ‘t’ is TOA and ‘ef’ is effective. 2)Let’s add CO2 as 300 ppm as for Earth The balance of radiative power is (missing the constants) xTt^4 + (1-x)Ts^4 = Tef^4 Tt/Ts = (Pt/Ps)^(R/Cp) Ht = (Ts-Tt)Cp/g where ‘x’ is the % of radiation in the CO2 bandwidth, ‘(1-x)’ the remaining radiation in all the spectrum, ‘P’, ‘R’, ‘Cp’ are well known by thermodynamics, ‘Ht’ is the eighth above the ground where P = 0.2 bar, ‘g’ is the gravity. The troposphere, cooled at the top and warmed at the bottom, becomes adiatically convective. Given x, the system is closed. If x << 1, then is Ts = (1+x/4)Tef, Tt/Ts = (0.2/90)^(299/1043) = 0.287, Ht = (1+x/4)(1-0.287)(1043/8.87)Tef/1000 = 0.0838(1-x/4)Tef kilometers. Assuming x=0.04, you have Ts = 1.01Tef, Tt = 0.29Tef, Ht = 0.082Tef. Notice that the mean temp passes from Tef to (Ts+Tt)/2 = 0.65Tef. If Tef = 240 K, then Ts = 242.4 K, Tt = 69.6 K, Ht = 15.6 Km, all more smaller than the real ones. So, adding CO2 you get a small GH effect at the ground and a strong cooling for the whole troposphere. The sole CO2 isn’t enough. 3) Clouds If there is a cloud layer at height Hc = aHt, with 0 ≤ a ≤ 1, then, the system above becomes xTt^4 + (1-x)Tc^4 = Tef^4 Tt/Ts = (Pt/Ps)^(R/Cp) Tc = Ts-a(Ts-Tt) Ht = (Ts-Tt)Cp/g Also, given x and a, the system is closed. Assuming the same values than above, you get Tc = 242.4 Ts = 242.4/(1-0.713a) Tt = 0.287Ts If a = 0.94, then, Ts = 735 K, Tt = 211 K, Ht = 61.6 Km. Very close to real values. Thus, the surface temperature is affected by the lapse rate caused by the CO2 and especially by the height of balance of the clouds liquid droplets, where their weight equals the viscosity of upwelling flow. It's all a team effort between fluid dynamics and radiative transfer.
62709. Chris G at 05:32 AM on 3 March 2012
       Wall Street Journal 'Skeptics' Misrepresent the IPCC
       I've been testing the water over at Dr. Curry's site. Some commentators are more rational than others. Anteros is currently in my bucket of those who fail the are-we-having-a-rationale-discussion test, for refuting the evidence I could reference with his, apparently, personal conviction.
62710. mdenison at 04:17 AM on 3 March 2012
       Wall Street Journal 'Skeptics' Misrepresent the IPCC
       It may help those following Anteros' link from real climate to "Lessons from Past Climate Predictions: IPCC FAR" if the older post had an update linking it to this post.
62711. Philippe Chantreau at 04:09 AM on 3 March 2012
       Scafetta's Widget Problems
       Density of the volumes? Boy, that ought to be some seriously interesting concept. Perhaps it's closely related to the density of the masses...
62712. Tom Curtis at 04:05 AM on 3 March 2012
       Greenhouse Effect Basics: Warm Earth, Cold Atmosphere
       Eric (skeptic) @52, this post is solely about the greenhouse effect itself, not about how the greenhouse effect will change with increasing CO2 (or other Green House Gas) concentrations. So, although it is true for CO2 that most of the change will be in the wings, as you put it, the absolute effect of current concentrations is strongest in the center of the band. Looking at the last diagram in the OP (from Conrath), you can see the lowest portions of the CO2 trough are about 70 degrees C cooler than the surface. Given the standard lapse rate, that means the effective altitude of radiation to space in those frequencies are is about 10 km. The small spike in the center is from even higher in the atmosphere, and in fact from the stratosphere which is why it is warmer than the surrounding trough. Working our way up the right hand side of the trough, we find small ledges at about 240 and 260 K, indicating the effective altitude of radiation for these frequencies are about 7 and 5 km respectively. Further to the right, at about a wave number of 800, there are two very small troughs that are also caused by CO2. (At least, I am certain the larger is, and I think the smaller is as well.) Clearly for these troughs, the effective altitude of radiation is 1 or 2 km at most. Working to the left, the very uneven series of troughs from wavenumber 350 to 550 are caused by water. The average altitude of effective radiation for these frequencies is 3 - 4 km, but highly variable depending on the exact frequency. These values are fairly representative. The effective altitude of radiation averaged across all frequencies in the IR spectrum is about 5 km. It should be noted that the "effective altitude of radiation" should be understood as (approximately) the average altitude from which radiation reaches space. It has a more technical definition, but for lay purposes treating it as an average is probably accurate enough. (Chris Colose can correct me if he thinks the technical definition is important.) As such, radiation at a given frequency may come from several kilometers above or below the effective altitude of radiation. Measurement of the effective altitude of radiation from space can be done much as I have just done, but using more accurate temperature measurements from radiosondes to calibrate the altitudes. It can also be done by determining the altitude of cloud features visible at particular frequencies. And, as scientists are usually very clever people, it may well have been done by other means I am not familiar with as well. I will leave discussion of how the green house effect changes with increasing CO2 to a later post on the subject, although for CO2, you are correct that the change in intensity (but not the effective altitude of radiation) is primarily on the wings.
62713. windbarb at 03:28 AM on 3 March 2012
       Nordhaus Sets the Record Straight - Climate Mitigation Saves Money
       Somebody smarter and with more time than me should create an analogy between a growing national deficit and a growing climate change mitigation deficit- something that would appeal to those who are inclined to see deficits as a major issue to be corrected by extraordinary means.
62714. desertphile at 02:44 AM on 3 March 2012
       Trenberth can't account for the lack of warming
       It should be stressed, I think, that Trenberth's "travesty" is still not completely resolved: only a partial amount of the "missing" heat has been (likely) found; there is still some heat that we know for near certainty that Earth has accumulated (via radiative measurements "in" and "out"), but where it all is has yet to be determined. I am not convinced Trenberth Fasullo (2011) has accounted for the bulk of the "missing" heat, due to the error bars. The "breakfast napkin" sum I did with the 2011 paper shows some 0.13 w/m^2 to 0.28 w/m^2 missing if the ocean retention hypothesis is correct (which it almost certainly is, but it might not be). The median of the "missing" heat has not been observed (yet). There is a grant proposal being submitted to a few science organizations that seeks to measure the increase (and decrease) in oceanic heat in all four dimensions (i.e., cubic meters over time) to a depth of about 2000 meters. How to do this is a very difficult problem, and it would take an massive amount of money to do properly, and that money will never be provided; but the grant proposal is to perform a short term (minimal ten years) sampling every ten meters. Each buoy would have 200 temperature probes. The problem is that the expense is so great that only a few (30 or so) could be funded, and that is no where near as many as needed: the world's oceans take up a very large volume. The project may never be funded, even for the 30 hoped-for buoy systems. The bottom line is that humanity will never measure with confident accuracy all of the heat gain and loss going on in the oceans. We can at best measure surface and near-surface temperatures, and thereby infer heat, but the error bars will always be wide.
62715. Bernard J. at 02:26 AM on 3 March 2012
       The Certainty Monster vs. The Uncertainty Ewok
       With respect to that painfully lame Josh 'cartoon', and with a hat tip to one of the themes of this thread, there is only one thing that I would say to the denialati who imagine humour in Josh's writing, and that is:

       These are not the interpretations that you are looking for...

62716. Eric (skeptic) at 02:15 AM on 3 March 2012
       Greenhouse Effect Basics: Warm Earth, Cold Atmosphere
       Tom, when you say "atmosphere radiates in those frequency bands from much higher altitudes, and hence at much cooler temperatures" Is that true across the CO2 absorption spectrum or just at the wings (e.g. see end of p. 4643 in http://www.meteo.mcgill.ca/~huang/research/JCLI2874.PDF)? My other question is how much is "much"? Are there satellite measurements of effective radiation altitude?
62717. Bernard J. at 02:09 AM on 3 March 2012
       Fritz Vahrenholt - Duped on Climate Change
       

       We cannot try to test eg the temperature with a given level of CO2 and all other factors being equal over and over again. Each of them will have moved on and be different so the circumstances that we need to test the theory in a meaningful way cannot exist.

       Either deliberately or mendaciously Elsa is confusing the difficulty of repeatability, with repeatability itself. Further, there comes a point where it is possible to account - both empirically and with repetition - for a certain number of parameters, and begging for more complexity adds no appreciable understanding to the system. In addition, having a repetition of a particular moment of the planet's climate is not a prerequisite for falsifiability, which seems to be Elsa's hook to try to claim that human-caused global warming is not testable science. As scaddenp notes, it seems that Elsa is not as familiar with the meaning of Popper's concept as she pretends. Falsifiability is eminently possibly with the physics of human-caused global warming, although once again it might not be simple to do so. However just because a scientific verification is difficult, it does not mean that it is non-scientific. And frankly, it would not difficult to falsify the physics of human-caused planetary warming... if it were indeed false. That it hasn't been falsified indicates the strength of the science, rather than the weakness. That denialists do not understand this fact indicates the weakness of their understanding of the science. On a related matter, 'simplifying' a description of a system by implying that a single dependent variable (global temperature) should always show direct and consistent correlation with a single independent variable (in this case atmospheric CO₂ concentration) is not scientific, and it most certainly does not constitute falsification. Scaddenp has explained this already, but is warrants repeating. That Vahrenholt sees fit to use this gambit is a sign of either his ignorance, or of his politics.
62718. Alexandre at 00:34 AM on 3 March 2012
       The Certainty Monster vs. The Uncertainty Ewok
       When the focus on uncertainties makes someone overlook the results before his eyes reminds me of that song by The Police: "a blind man looking for a shadow of doubt".
62719. Tom Curtis at 00:20 AM on 3 March 2012
       Greenhouse Effect Basics: Warm Earth, Cold Atmosphere
       dunc461 @49, there are no such things as stupid questions. I can understand how you reached your conclusion in that for CO2, nearly all absorption and nearly all radiation is in the wave number 600-700 band shown in the Modtran graph. However, it does not follow. Energy absorbed by CO2 (or any other green house gas) is likely to be transferred to other molecules by collisions long before it is reradiated. From there it may be transferred to water vapour, methane, ozone, or some other greenhouse gas, and radiated in an entirely different part of the spectrum. Of course, much of it is reradiated by CO2, but a significant proportion of the energy radiated by CO2 molecules may well have been carried to those molecules via absorption by other GHG molecules, or even be convection or transfer of latent heat. What is important, therefore, is not the individual paths of any given packets of energy, but the statistical effect of the overall process. That is governed by the fact that in certain frequency bands, nearly all energy radiated from the surface is absorbed in the atmosphere, and that the atmosphere radiates in those frequency bands from much higher altitudes, and hence at much cooler temperatures. The result is a significant reduction of the IR radiation to space from those bands, which must be compensated by higher intensity in those frequencies where radiation can escape to space, which is achieved by a warmer surface. The distinction between tracking individual packets of energy, and the statistical approach may seem like hair splitting to you. Not recognizing the difference does, however, lead to genuine confusions, some of which have motivated some persistent so-called skeptic "myths". In one case I know of, the fact that radiation from individual layers of the atmosphere is in fact half up and half down has led to the mistaken assumption that IR radiation to space must equal the back radiation in those parts of the spectrum absorbed by GHG. That is, of course, false. In fact, downward radiation at the surface is often much larger than the radiation to space because it comes from warmer, lower layers of the atmosphere, while that to space comes from the cooler, higher layers. On a related issue, when you follow the statistical approach, it becomes evident that the back radiation is not necessary for the green house effect (although it does exist, and is significant for some climate effects). In particular, because the lapse rate is independent of radiative transfer in the troposphere, even if there were no back radiation, a greenhouse effect could still exist by modulating the rate of energy transfer by convection to the upper atmosphere. I will be exploring this, and other issues in forthcoming posts in this series. In the meantime, I hope this has been helpful. Finally, I apologize if I was too abrupt in my first response to you. Regulars here can develop a hypersensitive alert system for trolling. The result is we sometime react to legitimate questions as though they were attempts at trolling. We should not do it, but we are human. If you ever read the full sequence of comments in the 2nd Law of Thermodynamics thread linked @48 above, you will understand why. So, if you think you have asked a silly question, it actually means I have just given a poor answer, for which I apologize. I hope this one is more helpful.
62720. Tom Curtis at 23:45 PM on 2 March 2012
       Greenhouse Effect Basics: Warm Earth, Cold Atmosphere
       CoalGeologist @45: Case 1: Suppose you have a planet which is a perfect black body, and perfectly conductive. Therefore, the outgoing radiation from the surface of the planet will equal the incoming insolation, and the surface temperature, T, will be (a) T = (I/4s)^0.25, where "I" is the incoming insolation and "s" is the Stefan Boltzmann constant. Case 2: Suppose we have instead the same planet, but now cloaked in an atmosphere which is perfectly absorbing (and emitting) wavelengths. In this case the atmosphere's temperature will be given by equation (a). In this case, because the atmosphere radiates equally up and down, initially it will be cooler, but as the surface warms beneath it, the upward radiation from the surface will rise to match the downward radiation from the atmosphere until both equal the incoming solar radiation. So the temperature of both atmosphere and surface will be given by the equation: (b) T_A = T_S = (I/4s)^0.25, where the subscripts indicate atmospheric and surface temperatures respectively. Note that in case (2), there is a lot more "pool table ricochets", but the temperature is not increased relative to case (1). Therefore increasing the time it takes for radiation to escape to space is not a sufficient condition to establish a green house effect. I have, of course used a slab model for this discussion, which is inaccurate in life, but allows clarity in seeing the relevant relationships.
62721. Dikran Marsupial at 23:36 PM on 2 March 2012
       Scafetta's Widget Problems
       Volker I also don't like repetition, so I will just address a couple of points. As KR, Scaddenp, Spherica and Skywatcher suggests, if you want your theory to be taken seriously, then yes, you do need a plausible physical mechanism. "I have refused your claim because I not agree with you on that analysis. A trained eye is able to see in a graph if there is a correlation or not. I have no possibility and no software to calculate a correlation coefficient. But each interested guy can perform such coefficient, because all date are public. It is not necessary that I must perform that. " This is wrong in almost every respect. Firstly we have statistics simply because the eye is unreliable, and an eye that has been trained to see correllations doubly so (as it will see spurious correllations even more readily). Secondly, there is a piece of statistical software called R which is in the public domain, so lack of software is no excuse for not performing the statistical analysis. If you don't understand statistics well enough to perform the analysis, then you need to be more receptive to the advice of those who do. Just measuring the correllation coefficient is easy, what you really need to do is to show that after having investigated the amount of data that you have looked at that it would be unusual to have found a match giving a coefficient as high as that which you observed. This is the test you need to perform to show that the coherence is nothing more than a random artefact. Your last point is the most egregious. It is your theory, this the onus is on you to perform the analysis to suggest that the theory is valid and to defend it against specific scientific criticisms. That is the way science works, whether you like it or not.
62722. dunc461 at 23:27 PM on 2 March 2012
       Greenhouse Effect Basics: Warm Earth, Cold Atmosphere
       Tom Curtis @43 Thanks again for your response and patience. My concern is not with the accuracy of the models but in trying to understand the process. Somewhere I picked up the concept that the greenhouse effect was caused by the absorption by certain gases of energy radiating from the earth’s surface at specific wave lengths and re-emitting that energy at the same wavelengths, but in all directions so that half of the energy re-emitted is directed back towards earth. This seem plausible to me because if the energy were re-emitted at whole range of wavelengths, some of the energy would be re-emitted in the “transparent windows” and the energy measured, at the top of the atmosphere, in those windows, would be greater than a Black Body Radiation Calculation would predict. Your answer seems to rule out both possibilities so I guess the entire concept is invalid. I apologize for bothering you with my stupid questions.
62723. Dikran Marsupial at 23:16 PM on 2 March 2012
       The Independence of Global Warming on Residence Time of CO2
       Michael Hauber As I have already pointed out to you, temperature is not the only factor controlling the equilibrium. Another important factor is the level of CO2 in the atmosphere. If you want to discuss hypothetical situations that are unrealistic of the actual carbon system, then that is fine, but is of limited interest to me. The fact that atmospheric CO2 levels are rising more slowly than anthropogenic emissions established beyon reasonable doubt that the natural environment is a net sink hand has been opposing the rise. Any argument that suggests that the oceans were degassing would require the terrertial biosphere to be taking up half of anthropogenic emissions AND the CO2 released by ocean degassing in order for mass to be conserved. Even in that case, the natural environment is still a net sink and is opposing the rise in CO2. Now as it happens, scientists have monitored the oceans, and we know that it is a net carbon sink. See the work of e.g. Corrine Le Quere.
62724. Tom Curtis at 23:09 PM on 2 March 2012
       Greenhouse Effect Basics: Warm Earth, Cold Atmosphere
       skymccain @47, not it is correct as written. In that form it exactly mirrors a common so-called climate skeptic argument. The argument made is that heat cannot flow from a cooler to a warmer location, and that therefore back radiation from the atmosphere (which is admittedly cooler than the surface) cannot result in the surface being warmer. In the analogy, the "mechanical breakdown skeptic" claims that the cool water cannot transfer heat to the warm engine block, so that even if the water gets warmer because of the broken pump, it will still be cooler than the engine block and therefore not capable of warming it. The presumed consequence is that the engine will therefore not run hotter because of a faulty water pump. Of course, nobody (or at least nobody sane) would run that argument about cars. But we are repeatedly challenged by so-called skeptics who have incontrovertible proof that "global warming is a lie", where the "proof" turns out be nothing more than the obviously false engine block argument transposed to the atmosphere. As of today, the thread I linked to has 1393 comment from repeated attempts by so-called skeptics to disprove fundamental laws of physics, and patient attempts to show them what is wrong with the argument.
62725. Dikran Marsupial at 22:43 PM on 2 March 2012
       The Independence of Global Warming on Residence Time of CO2
       owl905 The fact that CO2 levels had been pretty stable between 180ppm and 300ppm for the last 400,000,000 years, even during glaciations, is a pretty good indication that a balancing process exists. The natural carbon cycle has a stable equilibrium as the result of opposing feedback mechanisms balancing. If the equilibrium is peturbed, the balance is lost, and act is to restore the equilibrium. Such dynamic equilibria are common in the natural world. If we peturb the equilibrium with anthropogenic emissions, then the feedbacks will no longer be balanced (e.g. because carbon flux between the atmosphere and oceans depends on the difference in partial pressure between the surface waters and the atmosphere), and the natural environment becomes a net carbon sink, trying to retore the equilibrium. As for glaciation, the peturbation started by Milankovic cycles cools the oceans, which take in more CO2, which reduces the GHE slightly, ice caps grow, increasing abedo, which also results in cooling. The carbon cycle does re-establish the equilibrium, but it takes thousands of years to do so, just as it will take thousands of years to reestablish the equilibrium after we cease anthropogenic emissions (stabilisation will ocurr more quickly).
62726. fpjohn at 22:33 PM on 2 March 2012
       Nordhaus Sets the Record Straight - Climate Mitigation Saves Money
       Erp. I see the reference is now linked within the post. yours Frank
62727. fpjohn at 22:22 PM on 2 March 2012
       Nordhaus Sets the Record Straight - Climate Mitigation Saves Money
       The Nordhaus response is in the March 22nd issue of the New York Review of Books. http://www.nybooks.com/articles/archives/2012/mar/22/why-global-warming-skeptics-are-wrong/ yours Frank Johnston
62728. owl905 at 18:53 PM on 2 March 2012
       Nordhaus Sets the Record Straight - Climate Mitigation Saves Money
       Inaction is credit-card environmentalism. Someday someone else can pay the cost to clean up the mess. Anyone that didn't 'get it' from the Stern Report is likely still bunkered down and determined to have the right to freely pollute.
62729. owl905 at 18:46 PM on 2 March 2012
       The Independence of Global Warming on Residence Time of CO2
       Dikran 15 wrote: "If we cut emissions sharply enough that the net environmental sink outstrips anthropogenic emissions, then atmospheric levels will fall. The choice is in our hands." There's no evidence that such a process or balancing act exists. If the sinks had that magical power and capacity, atmospheric levels would not have stayed at interglacial peaks of 280ppm cycle after cycle. The dance-partners are temperature and moisture. The true significance of the pollution problem has been diagrammed out repeatedly over the last decade - temperature/GHG levels will remain charged for centuries, and future interglacial cycles will respect the additional GHGs in the biosphere. There's a research paper around somewhere that calculates real sequestered-removal is in the order of 2 ppm per cycle.
62730. skymccain at 18:41 PM on 2 March 2012
       Greenhouse Effect Basics: Warm Earth, Cold Atmosphere
       I enjoyed the post. "Suppose somebody told us their water pump was broken, but that the Second Law of Thermodynamics prohibited transfer of heat from a cooler place (the water) to a hotter place (the engine block), so they'ld be fine so long as they didn't rev any faster than normal, we'ld look at them in complete disbelief." Don't you mean "Suppose somebody told us their water pump was broken, but that the Second Law of Thermodynamics prohibited transfer of heat from a hotter place (the engine block) to a cooler place (the water)"?
62731. barry1487 at 15:21 PM on 2 March 2012
       Ice-Free Arctic
       There is an updated link to the full version of Polyak et al 2010 http://www.cgd.ucar.edu/staff/mholland/papers/Polyak_2010_historyofseaiceArctic.pdf
62732. owl905 at 14:59 PM on 2 March 2012
       The Certainty Monster vs. The Uncertainty Ewok
       Many posters here seriously underestimate Curry, and seem to figure the triumphant-truth shows the holes in her empress's new clothes. It's a dangerous underestimation. It hasn't shown holes - just added fuel to her fire. She certainly understands both the subject and the evidence. Her rejections and spin-twists aren't weakness - they're servants to her larger purpose. Her attack at the science has method and a very clear self-centred agenda. Her own words provide the motivation turning point - she was 'vilified' for recommending 'The Hockey Stick Illusion'. After that, she deliberately set about attacking 'the IPCC consensus'. She's selling, not telling - and she doesn't hide the reasons why.
62733. scaddenp at 13:50 PM on 2 March 2012
       The Independence of Global Warming on Residence Time of CO2
       Sorry didnt include sources: Fischer et al 2008 or Hinrich Schaefer, Michael J. Whiticar, Edward J. Brook, Vasilii V. Petrenko, Dominic F. Ferretti, Jeffrey P. Severinghaus 2006 Ice Record of 13C for Atmospheric CH4 Across the Younger Dryas-Preboreal Transition, Science 25 August 2006: Vol. 313. no. 5790, pp. 1109 - 1112 We report atmospheric methane carbon isotope ratios (13CH4) from the Western Greenland ice margin spanning the Younger Dryas–to–Preboreal (YD-PB) transition. Over the recorded 800 years, 13CH4 was around –46 per mil (); that is, 1 higher than in the modern atmosphere and 5.5 higher than would be expected from budgets without 13C-rich anthropogenic emissions. This requires higher natural 13C-rich emissions or stronger sink fractionation than conventionally assumed. Constant 13CH4 during the rise in methane concentration at the YD-PB transition is consistent with additional emissions from tropical wetlands, or aerobic plant CH4 production, or with a multisource scenario. A marine clathrate source is unlikely.
       Response:

       [DB] The Schaefer study can be found here (free download after free registration):

       http://www.sciencemag.org/content/313/5790/1109.abstract

62734. scaddenp at 13:43 PM on 2 March 2012
       The Independence of Global Warming on Residence Time of CO2
       "t is reasonable to suppose that this was the release of methane from clathrates trapped" However, isotopic evidence from CH4 in ice bubbles points to this being of swamp or oceanic source rather than clathrate.
62735. william5331 at 13:19 PM on 2 March 2012
       The Independence of Global Warming on Residence Time of CO2
       You would have to be incredibly blinkered to maintain that the carbon increase in the atmosphere is not anthropogenic. However, not to forget that atmospheric carbon increased sharply at the end of each glacial and was virtually certainly the result of the melting and not the cause. It is reasonable to suppose that this was the release of methane from clathrates trapped under the 3km of ice with the methane sourced from shale, coal and oil deposits over the 100k years the ice existed as well as from the anaerobic breakdown of organic material. On release it would have been rapidly oxidized to Carbon dioxide. If Greenland melts, there may be similar deposits waiting under the ice to further push global warming. http://mtkass.blogspot.co.nz/2011/08/end-of-ice-ages.html
62736. dhogaza at 12:39 PM on 2 March 2012
       The Certainty Monster vs. The Uncertainty Ewok
       "As I understand it, there are really only three options that can explain Curry's nonsensical hypotheses: 1) She has not read the ARs. 2) She has read the ARs, yet chooses to misrepresent and distort their content and even fabricate strawmen, 3) She is not well and is losing control of her faculties." When Curry first went public with her odd ideas, she engaged Gavin Schmidt in a lengthy thread over at RC. It was clear that either she hadn't read AR4, or she had only skimmed it superficially. She made many of the arguments then that she continues to make now, and Gavin and others did their best to educate her on what the scientific work that underlies the IPCC reports (and the reports themselves) say. She's been corrected a multitude of times since, including the responses to her "uncertainty monster" paper. Yet she's not budged an inch. It's possible that #2 is true but I wouldn't be surprised to learn that #1 (is still?) true. I don't think #3 is true. It's really frustrating to see someone in her position remain absolutely deaf to all attempts to educate her as to her mistaken assumptions about mainstream climate science. It's one thing when someone who's relatively uneducated like anthony watts refuses to learn. But a department chair at GIT? geez.
62737. scaddenp at 12:37 PM on 2 March 2012
       Scafetta's Widget Problems
       Hmm, when someone postulates that their forecasting tools are going to better than physical models, then I sense the possibility for a bet. So when do you think your "model" will deliver a climate that is outside the predictions of climate models?
62738. scaddenp at 12:32 PM on 2 March 2012
       Fritz Vahrenholt - Duped on Climate Change
       Elsa you are repeating "But the problem for your side in this is that it results in a theory that cannot be falsified." Repeating this does not make it true. Climate theory makes predictions all the time. For a given set of forcing, you will get a given climate. (ie a 30 year average). Even the primitive model that was basis for Broekner paper got climate for 2010 right within the constraints. Your comment on this was to complain that the paper didnt predict decade of only slowly rising temperatures. Well of course it didnt because even the most advanced climate model today has no skill at decadal predictions. I would note a recent comment from Gavin Schmidt. "Obviously people have thought of this and there are a number of ideas that are being tested - but none of them really give what it wanted (i.e. predictions that will reproduce the interannual ups-and-downs that you could compare directly to the obs). For instance, a lot of work is being done on initialised predictions where you take the ocean state for the last few years, attempt to synchronise the various 'oscillations' and then run it forward. This shows some skill for a few years in something like the AMO, but can't give realistic ENSO forecasts longer than the specialised ENSO forecasting systems (i.e. 6 months or so). So the interannual short-term variability doesn't seem to be predictable. There are also big issues with drift in these runs, which makes even the multi-year trends someowhat difficult to interpret. Another idea is run multiple ensembles for short periods, pick the one that is closest to reality and continue the next set of ensembles from that one and so on. But this only produces a plausible hindcast that is attuned to the actual interannual variations, not a prediction. The fundamental issue is that it is likely to be very hard (if not impossible) to predict ENSO phase 5 or 10 years ahead of time and that puts a real limit on how good any short term predictions can be.- gavin" You seem to be claiming that because you cant falsify a model with tomorrow's temperature, then its not falsifiable. This is wrong. Look at how well climate models predicted climate instead. Your "repeat but with one variable changed" approach does not work in many of the natural sciences. Fortunately we have developed the tools (contrary to your earlier false assertion) for dealing with multivariate hypotheses. It is possible to imagine all sorts of futures which would invalidate models.
62739. JP40 at 12:18 PM on 2 March 2012
       The Certainty Monster vs. The Uncertainty Ewok
       At least the title of this article makes sence. From my experience, the idea that there is actually a serious debate over climate change is what causes most inaction, not the actual arguments of the deniers.
62740. Albatross at 11:40 AM on 2 March 2012
       The Certainty Monster vs. The Uncertainty Ewok
       DSL, Curry still teaches and has grad students. My advice to any grad students considering enroling in the School of Earth and Atmospheric Sciences at GIT would be to run away and fast.
62741. Michael Hauber at 11:35 AM on 2 March 2012
       The Independence of Global Warming on Residence Time of CO2
       'Michael Hauber In the scenario you suggest, where the hypothetical sink were controlling atmospheric CO2 levels, the level would remain near the equilibrium level, rather than rising rather rapidly.' Not if the equilibrium level is determined by temperature, and temperature is rising rapidly. As an example, consider a see-saw with a small bucket on one side (atmosphere) and large swimming pool on the other side (ocean). Connect them with a pipe, and poor water slowly into the bucket, while tilting the see-saw so that the bucket gets lower and the swimming pool gets higher. With the right balance, it would be possible to pour water into the bucket at a rate faster than the water level in the bucket is rising. Water would be flowing through the pipe from the bucket to the swimming pool. But the level in the bucket would not be determined by the amount of water poured in, but by the tilt of the see-saw. I certainly do not believe that the oceans are responsible for the increase in Co2, but pointing out it is theoretically possible, unless you consider additional facts beyond what is presented in your argument.
62742. KR at 11:26 AM on 2 March 2012
       Scafetta's Widget Problems
       "... which is not the gravitation of Sir Newton, but the density of the volumes." I recall from the Cosmos TV series when Carl Sagan noted that the gravitational attraction of the obstetrician was larger than that of Jupiter, Saturn, or Mars - simply because (s)he was much closer. Thus throwing some severe doubt on astrology... Volker - Quite seriously, if you cannot point to a physical mechanism (a testable one, with some evidence), you are simply engaging in climastrology.
62743. skywatcher at 11:10 AM on 2 March 2012
       Scafetta's Widget Problems
       

       "... which is not the gravitation of Sir Newton, but the density of the volumes."

       Oh my! And next up from Volker, how white dwarf and neutron stars hundreds of light years away, with extreme densities (but somehow nothing to do with their gravity), control the future of the Solar System ... Sphaerica's point #57 resoundingly seconded!
62744. Bob Lacatena at 10:43 AM on 2 March 2012
       Scafetta's Widget Problems
       Volker,

       I do not need a mechanism...

       To be taken seriously, yes, you do.
62745. Volker Doormann at 10:25 AM on 2 March 2012
       Scafetta's Widget Problems
       Dikran Marsupial wtote at 07:12 AM on 2 March, 2012: “Volker, the scientific component of my objection was that you had not demonstrated that the coherence was anything more than temporary and actually existed throughout the satellite records.” I have demonstrated, and AFAIK as the _first_ researcher in climate, that there is coherence between the main frequency of the season cleaned sea level oscillations of the satellite records with the frequency of the heliocentric synodic tide function of the couple of Mercury/Earth over the whole time interval of the satellite measurements as a fact. I have no idea what mechanism is involved in that coherence; the fact is that the phase coherence shows high sea levels if the solar tide function shows spring tides and vice versa. And the high sea level peaks are also visible in global temperatures of the UAH satellite measurements as a higher temperature. If you call this a not more demonstration, that is your freedom; but I think it is worth to discuss it in the science community because a possible mechanism can bring more light into the basic question of the cause of the global warming. “I also pointed out that you had not performed a statstical analysis to see if a temporary coherence is surprising. Those are both valid scientific points, which you have refused to address.” I have refused your claim because I not agree with you on that analysis. A trained eye is able to see in a graph if there is a correlation or not. I have no possibility and no software to calculate a correlation coefficient. But each interested guy can perform such coefficient, because all date are public. It is not necessary that I must perform that. An other point is that the statistic tool is not an adequate tool to get a significance here; a significance is given better by a great number of comparisons of well known temperature reconstructions or proxies with the all the relevant solar tide functions, like A. Moberg et al, Bond et al, Zorita, R. Edwards, Mangini, G. Patzelt, and 10+ more, inclusive hadcrut3 and UAH. But as you know, there are differences between the proxies, maybe from different chemical processes in stalagmites and tree rings. I have done some hundred comparisons and have found by empery the strength of the tide functions of the several couples. “There is also the point that, like Scafetta, you need a plausible physical mechanism that can explain the strength of the effect, not just the correlation/coherence.” No, you are wrong. To realize a precise climate forecasting tool for the next millennium I do not need a mechanism, I do need only the NASA ephemerides and the empirical fitted tide function strengths. But nevertheless I have some hints about the physical background, which is not the gravitation of Sir Newton, but the density of the volumes. Rest snipped. V.
       Response:

       [DB] ...

       DNFTT, people.

62746. Dikran Marsupial at 09:44 AM on 2 March 2012
       Fritz Vahrenholt - Duped on Climate Change
       Elsa, Do you actually know which observations Plass used? Have you read the paper? Elsa wrote "But the problem for your side in this is that it results in a theory that cannot be falsified." This is not true, as I have already pointed out here where I wrote "If we have data or projections for the other forcings, then we can use the theory to determine/project the plausible range of the response to the combined forcings. If the observations lie outside that range then the theory is falsified. It really isn't rocket science." How do we disentangle the various effects of different forcings? Using something called an attribution study. There is a wide body of literature on this subject, start with the relevant chapter of the IPCC WG1 report. Thus it seems to me that not only are you unwilling to answer questions, you are also ignoring the responses to your assertions. As DB suggests, DNFTT seems the appropriate response. You had your chance to demonstrate that you were interested in the science by looking at the work of Plass; sadly it is clear that you are not interested in the answers to your questions.
62747. dana1981 at 09:43 AM on 2 March 2012
       Scafetta's Widget Problems
       Note, the figure shown by skywatcher @54 is essentially the same as Figure 6 in the post above (with a few minor differences).
62748. skywatcher at 09:35 AM on 2 March 2012
       Scafetta's Widget Problems
       I was constructing a response to a comment which made unsupported assertions, which has gone as I previewed, but for the benefit of readers, here's RealClimate's take on comparisons between AR4 models and data. Give me these over climastrological cycles any day! RealClimate 2011 update to model-data comparisons
62749. elsa at 09:23 AM on 2 March 2012
       Fritz Vahrenholt - Duped on Climate Change
       pbjamm (-Snip-)
       Response:

       [DB] The topic of this thread is Fritz Vahrenholt - Duped on Climate Change; please stay on-topic.

       Off-topic portion snipped.

62750. Daniel Bailey at 09:09 AM on 2 March 2012
       Fritz Vahrenholt - Duped on Climate Change
       And with this most recent comment, elsa stands revealed as full-blown troll. DNFTT.

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