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Comments 94001 to 94050:

94001. Albatross at 15:53 PM on 1 March 2011
       Climate sensitivity is low
       Tom @201, Devastating. Your last sentence also nails it.
94002. Tom Curtis at 15:46 PM on 1 March 2011
       Climate sensitivity is low
       RW1 @198:

       I admit I have not yet verified if what he's claiming is correct or not, but you have neither verified what the IPCC is claiming the 3.7 W/m^2 represents from the model simulations. I've looked all through the IPCC 2007 report, I don't find this information - they seem to be really ambiguous about where exactly the 3.7 W/m^2 is derived from. I've also looked all over the internet and cannot find verification either way.

       Let me reiterate what I first pointed out to you @209 on the "A Swift Kick in the Ice Thread" where this dicussion started; ie, that the IPCC explicitly claims that the radiative forcing from doubling CO2 is 3.7 w/m^2, and that "radiative forcing" is the change in net irradiance at the top of the atmosphere. To be quite clear, an increase in incoming radiation or a decrease in outgoing radiation both increase the radiative forcing, so a reduction in Outgoing Long-wave Radiation increases radiative forcing. Therefore, by simple logic, if the IPCC claims that doubling CO2 will increase radiative forcing by 3.7 w/m^2, then it is also claiming that doubling CO2 will reduce OLR by 3.7 w/m^2. The only way it does not have this implication is if changing CO2 levels in Earth's atmosphere could some how change the Sun's level of activity. So, what did the IPCC say in these mysteriously hard to find passages for which I have already provided you a link? The definition of Radiative Forcing:

       The definition of RF from the TAR and earlier IPCC assessment reports is retained. Ramaswamy et al. (2001) define it as ‘the change in net (down minus up) irradiance (solar plus longwave; in W m–2) at the tropopause after allowing for stratospheric temperatures to readjust to radiative equilibrium, but with surface and tropospheric temperatures and state held fixed at the unperturbed values’. Radiative forcing is used to assess and compare the anthropogenic and natural drivers of climate change. The concept arose from early studies of the climate response to changes in solar insolation and CO2, using simple radiative-convective models. However, it has proven to be particularly applicable for the assessment of the climate impact of LLGHGs (Ramaswamy et al., 2001). Radiative forcing can be related through a linear relationship to the global mean equilibrium temperature change at the surface (ΔTs): ΔTs = λRF, where λ is the climate sensitivity parameter (e.g., Ramaswamy et al., 2001).

       That was from section 2.2 of WG1 concealed under the obscure title of "The Concept of Radiative Forcing". The effect of CO2:

       The simple formulae for RF of the LLGHG quoted in Ramaswamy et al. (2001) are still valid. These formulae are based on global RF calculations where clouds, stratospheric adjustment and solar absorption are included, and give an RF of +3.7 W m–2 for a doubling in the CO2 mixing ratio. (The formula used for the CO2 RF calculation in this chapter is the IPCC (1990) expression as revised in the TAR. Note that for CO2, RF increases logarithmically with mixing ratio.) Collins et al. (2006) performed a comparison of five detailed line-by-line models and 20 GCM radiation schemes. The spread of line-by-line model results were consistent with the ±10% uncertainty estimate for the LLGHG RFs adopted in Ramaswamy et al. (2001) and a similar ±10% for the 90% confidence interval is adopted here. However, it is also important to note that these relatively small uncertainties are not always achievable when incorporating the LLGHG forcings into GCMs. For example, both Collins et al. (2006) and Forster and Taylor (2006) found that GCM radiation schemes could have inaccuracies of around 20% in their total LLGHG RF (see also Sections 2.3.2 and 10.2).

       That was carefully concealed in section 2.3.1 of WG1, titled "Atmospheric Carbon Dioxide". So what was it you wrote? That you've "...looked all through the IPCC 2007 report, I don't find this information - they seem to be really ambiguous about where exactly the 3.7 W/m^2 is derived from"? Really, you've looked all over, but never managed to look at the specific pages you were explicitly linked to? And specific mention of the types of models used, with references to three scientific papers that include the equations is being "really ambigous about where exactly the 3.7 w/m^2 is derived from"? Don't be absurd. Apparently you have also looked "all over the internet" with similar lack of success. But, again, without looking at the page that scaddenp explicitly linked you to. On that page you would have found a detailed discussion of all the issues raised here, along with images from a textbook, including the three @192 above showing the detailed mechanism used in calculating spectra in LBL models, and comparing LBL model results with reality. You would even find the actual formula (as if that would do you any good): And if that was not enough to clarify, you could always have looked up the actual textbook (as I have previously suggested). If that was not enough, you could also followed my link @192 above to SoD's seven part discussion of climate models and atmospheric physics in which he step by step builds an open code radiative transfer model. That is, of course, if your diligent search of the net had not already found it by noticing all seven posts in the "Recent Posts" section of SoD, or finding them in the "Atmospheric Physics" category (again, such careful concealment of information). If that was not enough, you have had, for over a hundred posts now, the opportunity to double check one well known radiative transfer model (Modtran) for internal consistency, as I linked you to that before the discussion came to this thread. Of course, that would be difficult and time consuming, just as it was difficult and time consuming for all those scientists who developed multiple models, and fact checked them against literally hundreds of thousands of observations, only to have their work dismissed by a electrical engineer who thinks his word is better than their about what the output of their models actually represents. And his acolyte. This whole discussion has become a waste of time. Clearly you will not do even basic research, and will not think about the outcomes of what research you do. I have long believed you are a troll, but have persisted in the discussion on the basis that interested readers may also have been confused by George White. Well for anyone who can think, it is diamond clear by now that George White's claim about the 3.7 w/m^2 radiative forcing from doubling CO2 is simply an error, and an error that anyone half way knowledgeable on the subject could not make. If you are still confused, it is because you want to be - you do not want to know the truth.
94003. Albatross at 15:11 PM on 1 March 2011
       Monckton Myth #15: Tragedy of the Commons
       Phila @25, Well stated, thank you. As a former resident of Africa I could not agree more with what you said. We westerners are by a long stretch (and sadly) totally alienated from nature, and it shows.
94004. Rob Honeycutt at 14:58 PM on 1 March 2011
       Australia's departing Chief Scientist on climate change
       BP... Please show me the research that backs up what you're saying.
94005. adelady at 14:34 PM on 1 March 2011
       Monckton Myth #15: Tragedy of the Commons
       Doug, if developing countries see carbon intensive industry as the "only" way to develop, that would be yet another nasty consequence of historical and virtual colonialism. If we are really concerned about this as an issue, then we should redouble our efforts to show, clearly, that the way we chose to develop our industry and society was not the best way. We now have a better way. You **can** skip the dirty step - you just have to choose.
94006. muoncounter at 14:31 PM on 1 March 2011
       Various estimates of Greenland ice loss
       BP, Your link to Vinther et al 2006 doesn't work; your link to 'supplementary data' is a txt data file that ends in 2005. How would a paper published in 2006 have data through 2009? In addition, Vinther only looked at the southwest coast. Here's a graph from their monthly data, averaged over summer and fall: Both summer and autumn have mild long term warming trends; both seem to turn up in the early '80s. Those seasons seem to be key to understanding Arctic melt: Per Serreze 2009 et al, "it makes sense that the surface warming signal has emerged first in autumn. Less sea ice at summer’s end (September), as observed, has enhanced upward heat fluxes to the atmosphere." Here's a more regional study, Box 2002: Based on temporal and spatial statistics, distinct and meaningful patterns of temperature are evident in Greenland instrumental temperature records spanning 1873–2001. These include a steady decay of spatial correlation, a lack of correlation between west and east coasts, and the presence of opposite temperature trends between west and east coasts that are themselves not statistically linked. So it would seem that no broad conclusions can be drawn from Vinther, which is just the southwest Greenland coast. Box (who analyzed 27 stations throughout Greenland) goes a step further: The 1873–2001 western Greenland warming trends observed in this study are meaningful in the context of observed Greenland ice sheet melt rates. The mass balance of the ice sheet sector south of 73°N latitude and west of Kap Farvel was negative for the second half of the last century. This appears not to be affected by changes in precipitation, implicating the observed warming and potential ice dynamical changes. Yeah, that negative ice mass balance just keeps on rearing its ugly head.
94007. wild monkeys at 14:31 PM on 1 March 2011
       Motl-ey Cruel
       I don't think it's surprising we can't see any "hot spot", as the effects of greenhouse effect are currently overwhelmed by arctic amplification.
94008. Tom Curtis at 14:28 PM on 1 March 2011
       Monckton Myth #15: Tragedy of the Commons
       Doug Proctor @18, 1) There is immediate feedback from a series of treaties in that you can immediately see who signs and who doesn't, and almost immediately see who complies with their obligations and who doesn't. 2) By proceding through a smaller number of treaties, you set up a reiterative process. 3) The arguments are perfectly valid. The question is, do we use our knowledge of game theory to set up a process that can avoid the worst of the coming catastrophe, or do we simply throw it all in the to hard basket, thereby sabotaging (by defecting) those who are willing to give it a go?
94009. RW1 at 14:27 PM on 1 March 2011
       Climate sensitivity is low
       "Having said that, I do not see the relevance to the basic point at issue - is it George White, or all the world's radiative transfer modelers who are correct in their interpretation of the output of radiative transfer models?" There is yet another possibility too. They assumed or convinced themselves that there was a remote possibility that the full 3.7 W/m^2 of incremental absorption could somehow make it back to the surface through multiple absorptions and re-emissions. I've seen this claim argued before, though ultimately never convincingly. Maybe they used this as a rationalization to count it all as a "just in case" precaution. I don't know. Without knowing the detailed specifics of the outputs of these model simulations there's no way to know.
94010. Tom Curtis at 14:23 PM on 1 March 2011
       Monckton Myth #15: Tragedy of the Commons
       Alex C @17, no! The problem with a long term agreement, even with penalty is that it is a one round prisoners dilemma. You either join the agreement, or not. By turning it into a succession of smaller agreements, you make the process reiterative. Best strategy in a one of prisoners dilemma is to default, while the best strategy in a reiterated prisoner's dilemma is some version of being nice at the start, and then reflecting the play of others. The term "Tragedy of the Commons" is used correctly in the main article as it is defined. However, that technically correct usage is a rhetorical device on a par with the various communist nations in the Soviet era calling themselves "Democratic Republics". It is used to justify, yet again, depriving people with traditional property rights of those rights without compensation for the advantage of commercial ventures.
94011. Phila at 14:23 PM on 1 March 2011
       Monckton Myth #15: Tragedy of the Commons
       Doug Proctor: Which all of us, not just Gore in his castle and Suzuki in his wilderness cabin, have a right to achieve. This is a common argument, with a grain of truth to it. However, when someone in the First World tells me, well-meaningingly or otherwise, that "the underdeveloped world sees carbon-based energy use more important to well-being" than some environmentalist cause, I tend to get irritated. Attempts to speak for the underdeveloped world have a fairly ugly history, and that ugliness becomes more pronounced the more monolithic their views are claimed to be. It can't be said often enough that poverty is not a synonym for ignorance or naivete. Many poor people around the world take a passionate interest in local and global environmental issues, and are interested in alternative forms of development (e.g., leapfrogging) and measures of wealth. In some cases, they may even be better informed about these issues than the average American, since problems that are abstract for many of us affect them directly. For this reason, and lots of others, we should hesitate to put words in their mouths, or treat them as some rubberstamp for our own ideologies. Instead, we should make an effort to find out how specific populations actually feel about issues like deforestation, pollution, climate change and so on. In other words, we should try listening to them, instead of treating them as a ventriloquist's dummy.
94012. hank at 14:22 PM on 1 March 2011
       Climate sensitivity is low
       Enjoy! http://www.modtran.org/ http://download.cnet.com/Modo/3000-2054_4-77505.html
94013. Berényi Péter at 14:16 PM on 1 March 2011
       Australia's departing Chief Scientist on climate change
       #15 Rob Honeycutt at 10:16 AM on 1 March, 2011 You just took it a little too far and started turning it into a political statement. The only remotely political statement was about my preference for saving people instead of a globe made of iron. I understand not everyone shares my priorities, but tolerance for expression of a diversity of opinions and beliefs is supposed to have some merit after all. Let's not forget it is a sui generis political thread where I've ventured that far. It is about the resignation of Dr. Sackett from a genuinely political post while quoting some of her political pronouncements like "I worry about this because there is actually something we can do about it and still we're not acting quickly enough." In other words, all the radiative physics related to the greenhouse effect is wrong. In one sweeping gesture you push 150 years of accepted science onto the floor so you can make your case. No, you have not read it carefully. There is nothing wrong with radiation physics. If there is a body heated by a steady incoming flux which is only radiatively coupled to its environment and its effective emissivity ε is decreasing while its absolute temperature T is increasing in a way that ε×T⁴ is kept constant, there is no heat accumulation in that body whatsoever. That is, as soon as its effective emissivity stops decreasing, its temperature also stops increasing. In this case there is no committed warming at all. Now, effective emissivity of Earth is not measured properly. If satellite measurements are to be believed, there's a 6.4 W/m² radiative imbalance, which is impossible. Direct measurement of heat accumulation rate shows it is negligible. Therefore the pipeline is empty, the radiative balance is almost perfect. It simply means the surface warming which has already happened was enough to restore balance. Of course we can not conclude from this that equilibrium climate sensitivity is small. But there's a somewhat subtler proposition which is true: it is either small or the time constants involved are huge. That is, either there's nothing to worry about or we have plenty of time for adaptation, so we can relax anyway. The conspicuous urgency in Dr. Sackett's public pronouncements is unwarranted.
94014. Marcus at 14:01 PM on 1 March 2011
       Prudent Risk
       Well done, RSVP, way to display your complete ignorance of biology-& most especially evolution. As has been pointed out to, the only reason viruses, bacteria & insects develop such rapid resistance is because of their extremely short life-cycles-which allows for the rapid accumulation of genetic mutations, one of which might lead to resistance & be passed on to the next generation-& even this can be overcome if you sustain the selective pressure strongly enough & for long enough (i.e. you can avoid antibiotic resistance in bacteria by maintaining exposure to a strong dose of antibiotics for a sufficiently long time. Longer lived animals & plants, who take months to years to decades to breed, develop the necessary mutations to survive selective pressures over a much longer time frame-a time frame that we're currently not giving them.
94015. TimTheToolMan at 13:47 PM on 1 March 2011
       Dispelling two myths about the tropospheric hot spot
       "1) It is very probable that Haig et al's result is either due to instrument error or to a atypical circumstances." The satellite used to measure the UV component of the TSI was purpose built for the task and doesn't have to deal with atmosphere or "winter night". The SIM data regarding UV level variability as seen above the TOA is what it is and is very probably correct. If you have an argument here it is how that data has been used in the Haigh paper. The problem is that the Frederick and Hodge paper you cited made its calculations based on the ground view of UV which is absorbed at varying rates in the atmosphere over time. And UV has also now been shown to itself vary over time. But most of all, "The goal is to define the variability in solar irradiance reaching the polar surface, with emphasis on the influence of cloudiness and on identifying systematic trends and possible links to the solar cycle." And then on top of all that, its goal isn't even to look at variation in the stratospheric temperature ranges. " taking Haigh et al's results at face value, they would predice a cooling stratosphere and a warming troposphere when the sun approaches a solar minimum" Taken at face value, Haigh et al shows that when TSI is thought to be low, its not because all components of the spectrum are uniformly low, rather they vary and so "Low TSI" doesn't necessarily mean low visible. By implication when TSI is high, we shouldn't assume that UV is also high or that visible is high, rather the combination (whatever that turns out to be when measured) is high. Regarding aerosols, that appears to be wishful thinking on your part. The effect of aerosols in our atmosphere is unknown. Every model has its own interpretation made on the dubious data we have and they cant all be right. Your point 3 is your real argument. Paraphrased (and correct me if I'm wrong) you're saying that CO2 has a particular fingerprint in atmospheric warming and reduction in UV has a different fingerprint. The problem with this argument is that the CO2 fingerprint has been deduced with the assumption (in the models) of how the atmosphere behaves and with "greater than expected" variance within TSI, this has turned out to be wrong. Before the CO2 fingerprint can be re-established, the models have to be corrected for the new knowledge about how solar radiation varies.
94016. Marcus at 13:28 PM on 1 March 2011
       Monckton Myth #15: Tragedy of the Commons
       Another point to consider though-regardless of its impact on *global* CO2 emissions a carbon tax-if it leads to a genuine reduction in coal & oil use-will result in significant side benefits to our local environment. The burning of fossil fuels is known to produce a number of highly toxic by-products (like benzene, mercury, cadmium, radon & particulate emissions) & the extraction of fossil fuels also does enormous damage to the environment. So a reduction in our use of fossil fuels *will* lead to significantly better environmental outcomes on a local scale.
94017. michael sweet at 13:28 PM on 1 March 2011
       Monckton Myth #15: Tragedy of the Commons
       Adelady, In Texas they are grid limited for wind in some areas also. A method needs to be developed to finance the wind grid to enable these projects to go forward. It will make money in the end but needs help to get started. This is where government organization can help the market get going.
94018. Marcus at 13:19 PM on 1 March 2011
       Monckton Myth #15: Tragedy of the Commons
       There is something else wrong with Monckton's argument though. As a major exporter of Coal, a carbon tax could send a significant price signal to those nations that buy our Coal &-therefore-maybe create an incentive for larger economies to use *less* coal. So whilst it might not have much *direct* impact on global CO2 emissions, it could impact it quite strongly through international trade.
94019. RW1 at 13:17 PM on 1 March 2011
       Climate sensitivity is low
       "Having said that, I do not see the relevance to the basic point at issue - is it George White, or all the world's radiative transfer modelers who are correct in their interpretation of the output of radiative transfer models?" Yes this is crux, but if GW is so obviously wrong as you claim, where is the smoking gun? And why haven't you presented it to him? I mean if it's so egregiously wrong, it should be easy to point directly to the specific evidence that disproves it, right? I admit I have not yet verified if what he's claiming is correct or not, but you have neither verified what the IPCC is claiming the 3.7 W/m^2 represents from the model simulations. I've looked all through the IPCC 2007 report, I don't find this information - they seem to be really ambiguous about where exactly the 3.7 W/m^2 is derived from. I've also looked all over the internet and cannot find verification either way. Regardless, I'm determined to get to bottom of this - even it means I have to get the MODTRAN software and run the simulations myself.
94020. Riduna at 13:13 PM on 1 March 2011
       Monckton Myth #15: Tragedy of the Commons
       Monckton advocates adopting a policy of self-interest, irrespective of the cost, because of his fallacious belief that no price need be paid. Not the first time Monckton has put forward this point and my response has been – we hang together or we hang (the environment) together. In other words, if we absent ourselves from pursuing the common good (GHG emissions reduction) because of perceived short-term political or economic gain, we risk paying a far greater price in the future. That price will initially be imposed by countries acting in the common good and in the longer term by catastrophic global warming and sea level rise.
94021. RW1 at 13:04 PM on 1 March 2011
       Climate sensitivity is low
       "Any substance with an emissivity greater will radiate energy with a total energy proportional to its emissivity times the fourth power of its temperature. That is where the radiation comes from, from the gases in the lower atmosphere which radiate in the IR spectrum and have non-zero temperatures (primarily water vapour and CO2). The heat that warms that gas comes evapo/transpiration from the surface, radiation from the surface, and atmospheric absorption of incoming solar radiation, although at any given layer, a large part of it will come from thermal radiation from adjacent layers, or convective heat transfer from adjacent layers." Agreed, but ultimately what matters here is the net combined effect of all these things relative to surface emitted radiation. Aferall, that's what we're talking about here is it not? That's what determines global average temperatures, right? Heat flows - how much from the surface is coming back from the atmosphere and how much is passing through. This is determining the heat flux or power flux at the surface, which ultimately is determining the temperature.
94022. John Chapman at 12:56 PM on 1 March 2011
       Monckton Myth #15: Tragedy of the Commons
       It is often maintained that Australia's 1.5% CO2 contribution is insignificant. Imagine a world of 100 countries each emitting the same amount of CO2, they would each claim to only contribute 1% and so in Monkton's world, they would each do nothing to curb their emissions. The planet has over 150 countries. Most of them could claim to produce less than 1% and carry on as usual. The per capita measure is the most appropriate figure, for which Australia's is much higher than China's. Each country, and at a smaller scale each individual, must be on board to reduce emissions.
94023. RW1 at 12:54 PM on 1 March 2011
       Climate sensitivity is low
       "What I am pointing out is that because not all energy transfers are radiative, situations can arise in which the atmosphere returns more energy to the surface than it receives from the surface. This will only happen when there is a temperature inversion, as sometimes happens with low lying clouds. In Antarctica in the winter it can happen on a continental scale because Antarctica is receiving no insolation, and there is still an energy transfer from the Antarctic Ocean to the Antarctic interior carries by the atmosphere. However, when you say "If some of the surface originating kinetic energy is radiated into the atmosphere and that energy is ultimately radiated out to space, the amount of kinetic energy returned to the surface will be less, having a cooling effect on the surface, effectively reducing the emitted surface power by the opposite amount", you appear to be making an error. Specifically, when energy is transferred to the atmosphere, it makes no distinction in the source of that energy when it radiates. So, the sum total of the energy it receives is radiated away, and half of that energy must be downwelling, and half upwelling. And if the sum of Insolation plus back radiation is less than the sum of Surface radiation plus energy transfer by evapo/transpiration and (a small) energy transfer by by collisions between gas molecules and the surface, then the surface will indeed cool. You also may be not making a mistake, and I have simply misunderstood you. It is true that the presence of evapo/transpiration and convection, by making energy transfer more efficient, cool the surface compared to the temperature it would be if all energy transfers in the atmosphere were radiative (about 70 degrees C). So in that respect, the fact that evapo/transpiration carries energy into the atmosphere, a portion of which does eventually escape to space does mean the surface is cooler than it otherwise would have been." Tom, All I'm saying is that globally, energy has to be conserved. Any kinetic energy moved from the surface into the atmosphere, some of which ultimately leaves radiatively at the top of the atmosphere, has to reduce the amount of emitted surface power by an equal opposite amount due to less being returned to the surface in kinetic form, which has the effect of reducing the surface temperature; thus reducing surface emitted radiation. I know about the Antarctic temperature inversion. It's highly localized.
94024. RW1 at 12:37 PM on 1 March 2011
       Climate sensitivity is low
       "Worse for your interpretation, a decrease in transmittance will automatically mean that a higher proportion of radiation from lower in the atmosphere is absorbed higher in the atmosphere, even with opticat thicknesss less than 1, but greater than 0. Because the higher gas is cooler (in the troposphere) it will radiate less energy, thus reducing the total IR radiation leaving the planet. That means a change in transmittance has more effect than simply reducing surface radiation to space." How do you figure? If anything, it seems a decrease in transmittance will shorten the height from the surface where the atmospheric absorption occurs. "The only way to properly calculate its effect is, as the LBL models do, calulate its effect on each layer of a large number of layers of the atmosphere (in modtran's case, 33). The LBL models take account of radiation flows in both directions. That is, for each layer, they determine its emission at each individual wavenumber (or wavenumber couplet for modtran), based on its temperature. They then apply that radiation as both upward and downwelling radiation. For each layer, they also take the total incoming radiation (upward and downward), multiply by the transmittance for that layer, and apply the result as upwelling or down welling radiation from that layer as appropriate. Because the transfers in radiation are calculated for each wavenumber, and for each level independently, there is no single calculation that corresponds to what you are seeking, ie, a level in which all incoming radiation is from the surface, and all upwelling radiation goes to space. But that does not mean that both the upwelling and downwelling emittance from each level is ignored, or that the absorption at any level is ignored which is what is required for George White's adjustment to make any sense." Have you verified with GW that this is what he's claiming? Because that's not my interpretation of it. The model simulations he's using are multi-layered through the atmosphere - he's simply showing the aggregate effect through all the layers. Is it just another coincidence that he's getting an incremental absorption or reduction in transmittance of 3.7 W/m^2 for 2xCO@ from his HITRAN based simulations?
94025. Berényi Péter at 12:35 PM on 1 March 2011
       Various estimates of Greenland ice loss
       #10 muoncounter at 11:14 AM on 1 March, 2011 "Not listening, not listening." Let's put recent warming over Greenland into perspective. The conclusion (based on evidence) is always the same. JOURNAL OF GEOPHYSICAL RESEARCH, VOL. 111, D11105, 2006 doi:10.1029/2005JD006810 Extending Greenland temperature records into the late eighteenth century B. M. Vinther, K. K. Andersen, P. D. Jones, K. R. Briffa & J. Cappelen Years 2006-2009 are added to their supplementary data.
94026. Tom Curtis at 12:30 PM on 1 March 2011
       Climate sensitivity is low
       RW1 @193: "And where does the radiation from the lower regions of the atmosphere come from?" Any substance with an emissivity greater will radiate energy with a total energy proportional to its emissivity times the fourth power of its temperature. That is where the radiation comes from, from the gases in the lower atmosphere which radiate in the IR spectrum and have non-zero temperatures (primarily water vapour and CO2). The heat that warms that gas comes evapo/transpiration from the surface, radiation from the surface, and atmospheric absorption of incoming solar radiation, although at any given layer, a large part of it will come from thermal radiation from adjacent layers, or convective heat transfer from adjacent layers. "So this is what you're claiming? That the 3.7 W/m^2 does NOT represent a reduction in total transmittance, as I have defined it? I just want to be clear." If your definition of total transmittance is "... the specific amount of emitted surface power that passes through the atmosphere unabsorbed and goes straight out to space", then no it is not. A small part is reduction of transmittance, but a more significant part is the reduction of thermal radiation from lower levels of the atmosphere to space, as per the diagram @171. "Define what you mean by correlation ..." The normal statistical sense. What I am pointing out is that because not all energy transfers are radiative, situations can arise in which the atmosphere returns more energy to the surface than it receives from the surface. This will only happen when there is a temperature inversion, as sometimes happens with low lying clouds. In Antarctica in the winter it can happen on a continental scale because Antarctica is receiving no insolation, and there is still an energy transfer from the Antarctic Ocean to the Antarctic interior carries by the atmosphere. However, when you say "If some of the surface originating kinetic energy is radiated into the atmosphere and that energy is ultimately radiated out to space, the amount of kinetic energy returned to the surface will be less, having a cooling effect on the surface, effectively reducing the emitted surface power by the opposite amount", you appear to be making an error. Specifically, when energy is transferred to the atmosphere, it makes no distinction in the source of that energy when it radiates. So, the sum total of the energy it receives is radiated away, and half of that energy must be downwelling, and half upwelling. And if the sum of Insolation plus back radiation is less than the sum of Surface radiation plus energy transfer by evapo/transpiration and (a small) energy transfer by by collisions between gas molecules and the surface, then the surface will indeed cool. You also may be not making a mistake, and I have simply misunderstood you. It is true that the presence of evapo/transpiration and convection, by making energy transfer more efficient, cool the surface compared to the temperature it would be if all energy transfers in the atmosphere were radiative (about 70 degrees C). So in that respect, the fact that evapo/transpiration carries energy into the atmosphere, a portion of which does eventually escape to space does mean the surface is cooler than it otherwise would have been. Having said that, I do not see the relevance to the basic point at issue - is it George White, or all the world's radiative transfer modelers who are correct in their interpretation of the output of radiative transfer models?
94027. Don Gisselbeck at 12:28 PM on 1 March 2011
       Monckton Myth #15: Tragedy of the Commons
       I said this on another thread and will repeat it here. Free market capitalism has no way of dealing with long term existential threats either to all or part of the system. After the money has been made destroying fisheries, forests, topsoil etc. capital will move on to exploiting the next resource. Unfortunately there is no next earth.
94028. Doug Proctor at 12:24 PM on 1 March 2011
       Monckton Myth #15: Tragedy of the Commons
       Tony Curtis: Iterative games or actions work when an action produces a result before the next action is required. With CO2 emission controls, this does not occur. A minor reduction in one area may show up as a reduction in the rate of increase, but will not show any improvement as the effect is global. The iterative game requires feedback - positive and negative - in a timely manner that allows the players to change their behaviour. A prisoner's dilemma or other such game also requires the game to be run a number of times. Here we have - according to CAGW theory - only one "set". When the results are in, it is too late. These arguments are not valid wrt CO2, global temperatures and one-sided actions. Except morally. Or that CAGW is not catastrophic, not a tipping point problem, not an immediate concern and not more suited for mitigation over the long run.
94029. Alex C at 12:11 PM on 1 March 2011
       Monckton Myth #15: Tragedy of the Commons
       Perhaps, Tom, that would be an argument for long-term agreements that would not require renewal? Binding, as it were. Fun political game that would be, the US faced with the option of agreeing to a binding international pact. I think, though, that the application of the concept of Tragedy of the Commons here is not a bad analogy. Emitters choose to not limit their impacts because they have no personal incentive to account for the full long term costs of their actions with respect to a public good, so overuse of the public good leads to depletion. Granted there is a twist in this analogy, as the public good - the climate, perhaps, and as used in the article - is not used up, merely altered to the point where it is largely harmful to participating individuals in the long term. I also don't think that the Tragedy of the Commons you bring up is the same being discussed here. I think this article is intentionally referring to the hypothetical situation described by Hardin in Science, 1968. http://www.sciencemag.org/content/162/3859/1243.full
94030. Doug Proctor at 12:08 PM on 1 March 2011
       Monckton Myth #15: Tragedy of the Commons
       The Nash game theory way to determine the correct course of action is valid only if one-sided action has an effect on the outcome. If AGW is really a global, catastrophic problem, then a 20% cutback of emissions by a portion of the world will not have a global impact. The rising emissions of underdeveloped nations will be the determinant. CO2 input into the atmosphere is presented as a global problem, moreover, with tipping points based on gross quantities, not rates of input, as no feedback mechanisms are presented in the models to say that nature will adapt to increased CO2 content without increasing the heat content of the world. One-sided action makes sense in three ways. The first is when the act-ers working against the problem show benefits the non-act-ers don't have. As the atmosphere is global and the effects are said to be global, not regional, CO2 reductions on one side won't give anyone any benefit. All cost, no profit. The second is where action is directed not at causes of problems, but their effects: we'd call that adaptation or mitigation. Changes of agriculture, building of dikes, removal of cities on low coastlines, etc. The example of personal benefit would be, of course, not to reduce CO2 emissions but to make mitigation worldwide. The third way is if the one-sided action aims at neither stopping the action or at mitigating, for some, harm. This is in the moral, philosophical or ideological realm. Shut-down your local economy by doing the right thing. However, since the AGW theme is actually catastrophe, not trouble, this way is about having your survivors, if not just God, think you honourable. It is said that you cannot cross a large chasm in a series of small jumps. Is A-CO2 emissions as occuring today a problem amenable to mitigating its effects or a developing catastrohe? Or is the global warming battle a physical issue representing an ideological position? I'd love an energy efficient lifestyle. More people could live as I do. But if, in spite of the "consensus", the underdeveloped world sees carbon-based energy use more important to well-being than a temperature rise that they, surely, will suffer the most, I do not support ineffective actions on our side. Calvinism is in my family background, but I note that even they gave it up as a poor way to a pleasant, successful life. Which all of us, not just Gore in his castle and Suzuki in his wilderness cabin, have a right to achieve.
94031. Bern at 12:02 PM on 1 March 2011
       Visualizing a History of CO2
       I like! [two thumbs up!]
94032. RW1 at 11:52 AM on 1 March 2011
       Climate sensitivity is low
       "given that at many frequencies, the atmosphere has an optical thickness greater than 1 (ie, transmittance is 0 for less than the full thickness of the atmosphere) than much of the IR absorbed by that region of the atmosphere that actually radiates to space does not come from the surface, but only from lower regions of the atmosphere. So an increase of absorption by 3.7 w/m^2 may have absolutely no effect on transmittance, or the atmospheric window (as you have defined it)." And where does the radiation from the lower regions of the atmosphere come from? So this is what you're claiming? That the 3.7 W/m^2 does NOT represent a reduction in total transmittance, as I have defined it? I just want to be clear. "Further, as much of the heat in the atmosphere is carried there by evaporation or transpiration, there is not even a necessary correlation between surface radiation and the thermal radiation of the lower levels of the atmosphere." Define what you mean by "correlation". I understand that a good amount of the heat in the atmosphere is carried there by evaporation and transpiration, but those amounts are in addition to emitted surface power and are non-radiative, which means they have to be returned to the surface in equal and opposite amounts, because all the infrared energy leaving at the top of the atmosphere is radiative. It's true that some of the kinetic energy moved into the atmosphere from the surface by evaporation and transpiration can radiate some energy into the atmosphere, but again it has to be offset by the surface radiation in equal and opposite amounts. If some of the surface originating kinetic energy is radiated into the atmosphere and that energy is ultimately radiated out to space, the amount of kinetic energy returned to the surface will be less, having a cooling effect on the surface, effectively reducing the emitted surface power by the opposite amount.
94033. Tom Curtis at 11:29 AM on 1 March 2011
       Preference for Mild Curry
       adelady @34, one of the most insightful comments I have seen.
94034. Tom Curtis at 11:28 AM on 1 March 2011
       Preference for Mild Curry
       rustneversleeps @32, I think you are right in your analysis of what Curry said, and why she said it. I would add, however, that she is probably aware that studies of climate sensitivity show far higher resolution of low values than of high values. That is evident in the change in her low and high end ranges for the 66% and 90% confidence intervals. Consequently her statement implies that she believes there is a substantive (at least 1%) risk that sensitivity is significantly higher than 10. However, I suspect her first back down would be to insist she was talking in round figures. That being the case, we should interpret her confidence intervals as: 1.49 to 5.5 for 66% confidence and 0.49 to 9.5 for 90% confidence Still very scary from a decision theory point of view, and pretty indefensible scientifically.
94035. rustneversleeps at 11:27 AM on 1 March 2011
       Preference for Mild Curry
       Rob @ 33, No doubt it was shoot-from-the-hip and unsupported, but I think the intent was primarily delay - by both playing up the big bad uncertainty boogie monster, and to argue that (extremely) low sensitivity is plausible enough to give us pause on action. In caually tossing out these bounds and probabilities - likely with little thought - she inadvertently wandered into cloud cuckooland at both ends. I don't think there was any subtle strategy aforethought, let alone a bridge-building one.
94036. Rob Honeycutt at 11:16 AM on 1 March 2011
       Australia's departing Chief Scientist on climate change
       BP... I also have to say your whole thesis is jaw-droppingly pretentious. You are claiming that, "...any talk on committed warming is based on conjecture, not facts." In other words, all the radiative physics related to the greenhouse effect is wrong. In one sweeping gesture you push 150 years of accepted science onto the floor so you can make your case. From that point, for you to be correct, you must completely redefine and re-explain a vast body of work spanning a wide range of sciences, something you do not accomplish in the few remaining paragraphs of your post. I'm sorry but I honestly think the moderators were doing you a favor by deleting your comment.
94037. muoncounter at 11:14 AM on 1 March 2011
       Various estimates of Greenland ice loss
       We've had Greenland ice loss threads here and here, among others. The conclusion (based on evidence) is always the same. The skeptical(?) response is likewise always the same. "Not listening, not listening." To me, this graphic at CCNY's Cryo Processes Lab speaks volumes: The figure above shows the standardized melting index anomaly for the period 1979 – 2010. In simple words, each bar tells us by how many standard deviations melting in a particular year was above the average. ... Previous record was set in 2007 and a new one was set in 2010. Negative values mean that melting was below the average. Note that highest anomaly values (high melting) occurred over the last 12 years, with the 8 highest values within the period 1998 – 2010. -- emphasis added
94038. Tom Curtis at 11:12 AM on 1 March 2011
       Preference for Mild Curry
       doghza @26, 10 degrees climate sensitivity means about 11 degrees temperature increase by 2100, with another 4 in the pipeline on Business as Usual. With that high a climate sensitivity, I think the real risk we are facing is not massive economic disruption and human hardship following drought, but of a Venus style runaway greenhouse. Of course, I'm not the one saying there is a 5% chance climate sensitivity is that high, or higher.
94039. Tom Curtis at 11:03 AM on 1 March 2011
       Climate sensitivity is low
       RW1 @190 &191, given that at many frequencies, the atmosphere has an optical thickness greater than 1 (ie, transmittance is 0 for less than the full thickness of the atmosphere) than much of the IR absorbed by that region of the atmosphere that actually radiates to space does not come from the surface, but only from lower regions of the atmosphere. So an increase of absorption by 3.7 w/m^2 may have absolutely no effect on transmittance, or the atmospheric window (as you have defined it). Further, as much of the heat in the atmosphere is carried there by evaporation or transpiration, there is not even a necessary correlation between surface radiation and the thermal radiation of the lower levels of the atmosphere. Certainly that correlation is broken over antarctica in the winter, and may be broken at other places periodically as well. That is why Line By Line models use temperature profiles in developing their predictions, either a simple lapse rate (as in Modtran) or measured (or modelled) values in more sophisticated programs. Worse for your interpretation, a decrease in transmittance will automatically mean that a higher proportion of radiation from lower in the atmosphere is absorbed higher in the atmosphere, even with opticat thicknesss less than 1, but greater than 0. Because the higher gas is cooler (in the troposphere) it will radiate less energy, thus reducing the total IR radiation leaving the planet. That means a change in transmittance has more effect than simply reducing surface radiation to space. The only way to properly calculate its effect is, as the LBL models do, calulate its effect on each layer of a large number of layers of the atmosphere (in modtran's case, 33). The LBL models take account of radiation flows in both directions. That is, for each layer, they determine its emission at each individual wavenumber (or wavenumber couplet for modtran), based on its temperature. They then apply that radiation as both upward and downwelling radiation. For each layer, they also take the total incoming radiation (upward and downward), multiply by the transmittance for that layer, and apply the result as upwelling or down welling radiation from that layer as appropriate. Here is a diagram illustrating the process from Science of Doom: Although this only indicates transmittance in one direction, be assured it is calculated in both. In the thread from which this comes SoD is developing a simple radiation model, and you can see in the code that he makes the calculations first for upwelling, and then for downwelling radiation. (By the way, this illustration also appears in SoD's thread on theory and experiment in atmospheric radiation, from which I got the diagrams which showed the close correlation between the model predictions and observations. That thread has already been linked here. So your claim that all you have received is statements, not evidence, is nonsense.) Because the transfers in radiation are calculated for each wavenumber, and for each level independently, there is no single calculation that corresponds to what you are seeking, ie, a level in which all incoming radiation is from the surface, and all upwelling radiation goes to space. But that does not mean that both the upwelling and downwelling emittance from each level is ignored, or that the absorption at any level is ignored which is what is required for George White's adjustment to make any sense. Of course, in the LBL models, the total upwelling radiation of the highest level (emitted and transmitted) is just the Outgoing Long-wave Radiation. And the difference between that for 375 ppm and for 750 ppm is the increase of the greenhouse effect for doubling of CO2. So, if you want to verify Modtran, and all the other LBL models programed by different teams around the world, and all the energy balance models also programed by different teams around the world, which all come up with essentially the same result; which just happens to match observations almost exactly, you either need to accept the observational match as confirming the models, or you need to go through the models line by line. There is no other short cut.
94040. adelady at 10:58 AM on 1 March 2011
       Various estimates of Greenland ice loss
       Flatlining? Even it it were flat, there's still the main issue. I suppose I can say I'm standing on a flat surface on each step of a staircase. However, even the most naive acknowledge that it makes a difference whether that "flat" surface is ankle-height above the surrounding level or head and shoulders above that level. We're into head and shoulders territory now regardless of the flatness of the terrain.
94041. adelady at 10:48 AM on 1 March 2011
       Preference for Mild Curry
       I spend a fair time on education discussions. It just occurred to me that Curry looks an awful lot like those naive teachers and administrators who go into those out of control classrooms or schools. They have the apparently laudable objective of getting "on-side" with the trouble-makers who won't learn anything themselves and spend all their efforts on disrupting the learning of others. And where does this get these misguided teachers? The troublemakers learn that bad behaviour gets not only no penalty, but real benefits. So more students behave more badly because they see no point in hard work or good behaviour - and they too get kind words and a fizzy drink as consequence of deliberately disruptive behaviour. Sound familiar to anyone else?
94042. Rob Honeycutt at 10:36 AM on 1 March 2011
       Preference for Mild Curry
       rustneversleeps @ 32... I get the distinct sense that she was firing from the hip with that statement. I don't think it's based on anything other than she wants to play both sides somehow. She wants to appease the denier crowd by saying climate sensitivity could be in the range of zero (which seems insane being that we don't have a perfectly stable climate over long periods), and she wants to appease the pro-AGW crowd to suggest that sensitivity could be a terrifying 10C. If she's building a bridge here it's not made with anything of substance as far as I can see.
94043. Rob Honeycutt at 10:16 AM on 1 March 2011
       Australia's departing Chief Scientist on climate change
       BP... I read through it and I see exactly why it was deleted. Go to the comments policy statement: "No politics. Rants about politics, ideology or one world governments will be deleted." You just took it a little too far and started turning it into a political statement. We've all had comments deleted for going a little too far over the line.
94044. Tom Curtis at 10:11 AM on 1 March 2011
       Monckton Myth #15: Tragedy of the Commons
       Shoyemore @9, this is in fact a prisoner's dilemma, which is what makes it so difficult policy wise. The trick for effective policy is to turn it into a reiterative prisoners dilemma. In a reiterative prisoners dilemma, participants can choose a policy, and observe how the policy chosen by others. Because there are multiple rounds, it becomes possible to adjust your policy based on the behaviour of others. Analysis in games theory shows it is very hard to beat a tit-for-tat strategy in a reiterative prisoners dilemma. In that strategy, you choose the "nice" option first, and then respond to other players by doing whatever they did in their last move. In this case, by targeting small steps in reducing green house emissions, you make each successive reduction a new game in the prisoner's dilemma, thus making it a reiterative prisoner's dilemma. Following tit-for-tat, you then reduce emissions in the first round. If others do not reduce, you then do not reduce in later rounds. If others reduce, you continue with further reductions. Importantly, the reverse strategy of "defecting" in the first round, and then repeating what your opponents do does poorly in reiterative prisoners dilemmas. As it happens, that is the policy we have been following. We have defected on Kyoto, and defected again last year. There is more to this, which I'll probably elaborate when deniers start attacking this analysis ;) On a side note, I do not like the terms "tragedy of the commons". It was invented as a rhetorical device to aid a political push for an "enclosure" movement for the high seas. The true tragedy of the commons was, in fact, the enclosure movement in Britain whereby the common law rights of tenants to grazing land, or inheritable leases were repudiated by land lords in order to make large grazing areas for sheep. That tragedy, the deprivation of ill defined, but actual property rights of the poor, by the rich for commercial benefit continues to today in Israel, Indonesia and no doubt many other countries; and indeed was the basis of colonialism.
94045. RW1 at 10:03 AM on 1 March 2011
       Climate sensitivity is low
       Are you claiming that the 3.7 W/m^2 of additional absorption from 2xCO2 does NOT represent a 3.7 W/m^2 reduction in transmittance? What I don't think you understand is that unless the specific wavelengths are saturated, some of the outgoing surface power still passes through them unabsorbed, and this amount is included in the transmittance. Increasing the concentration of CO2, for example, will reducing the amount that passes through at wavelengths NOT already saturated (i.e. widening the band or deepening the trough). The effect of more CO2 at saturated wavelengths will just reduce the height from the surface where 100% absorption occurs.
94046. Alexandre at 09:56 AM on 1 March 2011
       Monckton Myth #15: Tragedy of the Commons
       
94047. Alexandre at 09:56 AM on 1 March 2011
       Monckton Myth #15: Tragedy of the Commons
       Shoyemore #10 Thanks for the link, I'll have a look. Global warming is arguably the worst-case scenario for common-pool dilemmas: no way to keep new users out of the resource, now central legal system to enforce rules, difficult to monitor, a huge amount of users (everyone in the world, basically), etc. Basically we need a rule that respects the carrying capacity of the resource, and a way to enforce it. Self-regulation usually works better then centralized ones, because they're closer to the reality of the resource, and users are more commited to it. In the AGW case, I think this can be translated as general goals (both global and each country), but different rules for countries and industries. For example, here in Brazil a tough anti-deforestation law with an adequate enforcement would yield much better results than carbon markets, for instance. But this would be innocuous in the US or Germany. Some industries would have good results with a fuel tax, others with efficiency standards (maybe self-regulated ones). International treaties will be necessary at some point, but it does not have to start there. I remember the EU made an offer to unilaterally comit itself to emission targets, and made a public statement that they would improve that target if other countries made similar commitments. That's a clever way to overcome such dilemmas. Industry standards, including tough import rules would favor exporting countries (like China) to improve their own standards - as suggested by Tom Friedman. It's really a huge subject, and I resent the fact that all this effort in responding to denialist crap prevents us to really embrace this much more important part of the debate.
94048. rustneversleeps at 09:53 AM on 1 March 2011
       Preference for Mild Curry
       Andy S @ 21: "It's a pity that we have to guess what she means." I don't think we have to guess at all. On the thread where she makes the assessment, first she responds to Zeke's statement of "likely" (>66%) climate sensitity by saying: I think we can bound this between 1 and 6C at a likely level, I don’t think we can justify narrowing this further. Asked to clarify what she means, she says: That there is a 33% probability that that actual sensitivity could be higher or lower than my bounds. To bound at a 90% level, I would say the bounds need to be 0-10C. (My highlights.) She's not talking about whether the quality of the data allows you to make such-and-such a bounded estimate, or the accuracy of the measuring devices or anything like that. She is clearly saying that there is a 33% chance that the ACTUAL climate sensitivity is outside of the range of 1-6C, and a 10% that it is outside of 0-10C. I mention this only because an apologist tries to dodge this on the next thread, by talking about confidence intervals - which with enough convoluting you might be able to shy away from this. But that's NOT what Curry is saying. She is outright declaring that the PROBABILITY is that the actual sensitivities are outside those bounds. Now, yes, we don't know how she is assigning that probability to the low and high ends. But we're not guessing that this is exactly what she said. Whether she meant to say this is another matter... I suspect she'll walk back from this in some way, but if so I think we should again press for a clear articulation of what she means...
94049. dana1981 at 09:53 AM on 1 March 2011
       Preference for Mild Curry
       Rob #29 -

       "even if Mann and others had completely cooked the data, ultimately it wouldn't even matter. If they are wrong their work will disappear into obscurity."

       In fact we saw this was the case with the IPCC. Even if there are valid criticisms of the way the TAR handled the tree ring data, the IPCC was even more thorough and explicit about it in AR4. Of course, that didn't stop Curry from lumping both reports together in her extreme accusations, but it proves your point that flawed science gets supplanted. Same thing for the "hockey stick". It was a good first effort, but imperfect. Now millennial temp reconstructions all show a bit more natural variability over the past 2,000 years. The "skeptics" continue to obsess over the 11-year-old reconstruction, but it's been supplanted with even better scientific work. Including by Mann himself! I agree it's unfortunate that Curry seems to be mired over a decade in the past on a very minor issue. It's not worth wasting time over.
94050. Berényi Péter at 09:51 AM on 1 March 2011
       Australia's departing Chief Scientist on climate change
       #10 Ken Lambert at 12:20 PM on 28 February, 2011 I read and copied (luckily) a long post from BP. It corrected Bern's numbers. It has been deleted without comment by moderators. It should be compulsory reading for all SKS contributors. John Cook et al; this is unwarranted censorship of a valuable contribution which will do harm to the credibility of this site. Yes, it will. The more so because I've tried to respond to the act of deletion and KR's comments on it, but that post was also deleted. Anyway, here is the original one for anyone to see. Just make sure you've passed the Age-Verification Test before proceeding, please.

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