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Comments 89701 to 89750:

89701. CBDunkerson at 23:02 PM on 7 April 2011
       Arctic Ice March 2011
       Gilles: "The graph from Kaufman et al. 2009 that I reproduced just above obviously contradicts this assertion." Let me guess, this is based on a 'highly scientific' eyeballing of the chart? If you actually measure out the years between 1500 and 2000 I think you'll find that the relevant values are (to the nearest 0.1 C); 1900: -0.2 1950: 0.0 2000: 1.0 So no, that graph does not 'obviously contradict' my statement that the more recent warming has been much greater. Also: "And the biological proxies that are essentially summer responsive do show a much clearer increase at the beginning of century than now" Source? Finally: "Fine : so please can you predict the trend , say, in the 10 next years, and how ?" Actually, I'm of the school of thought that the Arctic ocean will be largely ice free at the annual minimum by then. A decent writeup on this position can be found here. The next three years or so should clear up alot of the remaining uncertainty about where Arctic sea ice is headed. Best case scenario, the volume will level off soon and we can then look forward to a longer slow decline down to largely ice free in September around 2035. On the other hand, if volume continues to drop at anything like the rate it has been then we'll be seeing ice free Septembers by around 2015. It all depends on what the dominant factors driving recent ice decrease have been. To my thinking the data since 2007 suggest that increasing influx of warm water and stronger currents have become the most significant factors, and thus we are likely to see continued declines. If, on the other hand, direct greenhouse warming of the Arctic region is still the dominant driver then we'd see a more gradual decline (though it then becomes difficult to explain the recent sharp drops).
89702. daniel maris at 22:53 PM on 7 April 2011
       Has sea level rise accelerated since 1880?
       Muoncounter Well from your point of view, my approach is not a problem since I support a swift march to 100% renewable energy use starting now. I think we could do it within 20 years if we had the will. The latest from Israel where they are trialling battery changing statinos for cars suggests the range problem with electric vehicles has been resolved, so we can now look at a more or less complete and all-embracing solution. My reasons for favouring 100% renewables are many and various but do include a precautionary approach to altering carbon levels. But to adopt a precautionary approach is not the same as saying I buy into the reality of AGW yet. My view is that sea level rises would happen sufficiently slowly for humanity to react effectively. No relation to that Maris!
89703. les at 22:45 PM on 7 April 2011
       2nd law of thermodynamics contradicts greenhouse theory
       979 Tom - "What more could we ask for..." I wait, with trepidation, to find out! To me, it all seems so straightforward. Still, just because this discussion has certainly not gone on long enough - nor has it been repeated nearly sufficiently enough times on nearly enough blogs - can I suggest a further place for doubt? It turns out that in many multiverse models it is not clear that conservation of energy holds for the whole universe nor, indeed, for every universe. As such, I'm guessing I admit, it should be possible to have infinitely many universes in which the 2nd law doesn't hold, or possibly doesn't hold only for those gases which don't transmit/radiate/absorb evenly at all wavelengths or something. see, always room for doubt.
89704. Tom Curtis at 22:42 PM on 7 April 2011
       2nd law of thermodynamics contradicts greenhouse theory
       Fred Staples @976, I believe Les has adequately rebutted your comments about SOD.

       For any spontaneous transaction, anywhere in the known universe, the change in entropy must be positive.

       This is incorrect. The Earth is infested with a spontaneous transaction which results in the formation of very low entropy products. It is called life. Of course, if you look at all energy flows involved in life, then the net entropy of the whole system increases, even though that in the living system decreases temporarily. So, only when we account for all energy flows within a boundary can we apply the 2nd law to the system within the boundary, and then it applies only to the entropy of the whole system, not to any arbitrary subpart of the system. As the worked example quoted above shows, when all energy flows are accounted for, the interchange of energy between Earth and atmosphere including back radiation involves a net gain in entropy, and hence no second law violation. And the second law applies only to the whole system, not to any arbitrary subpart - say, the backradiation alone.

       "Now if a quantity of energy deltaQ leaves the atmosphere at a temperature Ta, ..."

       Plainly your accounting considers only one energy flow within the system, not all of them. Therefore it is an attempt to apply the second law to an arbitrary subpart of the system rather than to the system as a whole, which is as explained above, a misapplication of the second law.
89705. MichaelM at 22:34 PM on 7 April 2011
       Arctic Ice March 2011
       Prior to 1940 there seems not to be great deal of variance from: Winter 1 - 15 (Million sq k) Summer 1 - 11 Winter 2 - 15 (4 million k new ice) Summer 2 - 11 ... So 11 million k got to be multi-year ice i.e not "most of the ice in winter is just 6 months old anyway, every year". That we have less multi-year ice now is symptomatic of the problem. Or the above usage of 'most' could be just a language thing.
89706. Ken Lambert at 22:29 PM on 7 April 2011
       A Flanner in the Works for Snow and Ice
       Tom Curtis #42 "Frankly, the implied dictum that you should only present some relevant information if you can present all relevant information is nonsense. What is more, it not one you adhere to, for if you had, you would not have made an argument based solely on the minimal relevant information of relative surface area of the arctic to the globe." Tom, wilfully leaving out relevant information of which you are aware simply is a distortion of the case to suit a particular bias. I did not rely 'Only on the surface area' of the Arctic to make my points. I quoted the calculations of the leading energy balance scientist in this field - Dr Trenberth. You say that Flanner has calculated that the heat sequestered in the Arctic is something like 9-10E20 Joules/year instead of 1E20 Joules/year from Trenberth's melting Arctic ice. The difference is supposed to be in the ocean. Well - where is your measurement of that? By the way if the imbalance portion is in fact 9-10E20 rather that 1E20 Joules/year then you were only wrong by 15 times rather that 149 times in your claim. I would like to see you out by only 100% rather that 1500% - however we can't have it all. If Dr Trenberth's 145E20 Joules/year net heat gain to the Earth was evenly distributed all over the surface then the Arctic's 4.4% would account for 6.4E20 Joules/year, which is still less than the 9-10E20 Joules/year claimed in Flanner. I cannot see how the high latitude areas of the Earth at incidence angles of +23 to -23 degrees could have the same area portion of heat gain as the tropics.
89707. Tom Curtis at 22:24 PM on 7 April 2011
       2nd law of thermodynamics contradicts greenhouse theory
       Les @977, an excellent read, and profitable for anyone following this debate. I particularly liked propater's comment:

       "If you take ScienceOfDoom example 3 and reverse it to consider radiation emmited by the atmosphere and absorbed by the earth’s surface, you can see that entropy is lost when the radiation from the atmosphere is absorbed by the hotter surface : Atmosphere: δS1 = -(390-301)/270 = -89 / 270 = -0.33 J/K Surface: δS2 = (390-301)/288 = 89 / 288 = 0.31 J/K This is right, net entropy equals -0.02J/K (as you say, “radiation quality” has increased since that energy will be re-emitted at a shorter wavelength) Entropy is reduced. This looks wrong. And it is! Because in that calculation you forgot one term: the radiation from TOA to space : If we suppose radiation from space to be j* = sigma * T^4 = 5.67*10^-8 * 3^4 = 4.59*10^-6 W/m² Let’s consider the entropy budget for one square meter for a second : Atmosphere: δS1 = -(390-0.00000459)/270 ~= -390/ 270 = -1.44 J/K Space: δS2 = (390-0.00000459)/3 ~= 390/ 3= 130 J/K Net entropy production from TOA-Space exchanges : 128.56 J/K Net entropy production from atmosphere exchange with the earth’s surface and space : 128.56 J/K – 0.02 J/K = 128.54 J/K. When you take all terms into account, no entropy is lost (even though some of it gets moved away.) In fact you see a massive amount of entropy created and, as Nick Stokes points out, it is the place where the entropy production is the largest (Sun-earth ~ 10 J/K.s.m², earth-atmosphere ~ 10^-2 J/Ksm² , atmosphere-outer space ~ 10² J/Ksm² )"

       What more could we ask for - an actual worked example proving that back radiation does not violate the 2nd law of thermodynamics. Given this example, and the ease of the mathematics, I think it should be a minimum denier wanting to mount the tired old 2nd law argument that they provide such a worked example of their model of the greenhouse effect. It should make the arguments much shorter and to the point, and provided an easy way to keep score of who is correct, and who is simply full of it.
89708. Ken Lambert at 22:10 PM on 7 April 2011
       Skeptical Science in other media
       I did not think that being forgiven by supernatural beings had anything to do with the science (or sub-science) of AGW. I must admit that if there were a logic to an object of worship - worshipping the Sun made primitive and scientific sense. After all, from the Sun is where all this troublesome warmth cometh.
89709. Gilles at 21:59 PM on 7 April 2011
       Arctic Ice March 2011
       Michael : "winter ice used to be 15 million sq k and dropped to 11 in the summer i.e 4 million was new ice." ??? 6 months after being 15 or 10 millions km^2, winter ice becomes summer ice , with an extent between 4 and 5 Mkm^2 - so most of the 10 to 15 Mkm^2 of each year are only 6 months old anyway.
89710. Gilles at 21:55 PM on 7 April 2011
       Arctic Ice March 2011
       162 : les: I'm flattered that you waited until I didn't recognize a famous sentence before concluding english is not my mother language (I'm French - it's "Gilles" and not "Giles").But CB 164 : "However, they can and have been used to predict the trend of the decline." Fine : so please can you predict the trend , say, in the 10 next years, and how ? "Arctic temperatures have risen much more in the recent warming phase than they did in the earlier part of the century." The graph from Kaufman et al. 2009 that I reproduced just above obviously contradicts this assertion. And the biological proxies that are essentially summer responsive do show a much clearer increase at the beginning of century than now - so how do you explain that tree and lake sediments appeared to feel much more variable warmth in summer, at the beginning of the XXth century than sea ice ? another try ?
89711. Tom Curtis at 21:53 PM on 7 April 2011
       Muller Misinformation #1: confusing Mike's trick with hide the decline
       Ryan Starr @123, it is a common conceit of deniers that any absurdity they do not adhere to is not promulgated by any denier. By ignoring the claptrap sprouted by their fellow deniers, they not only avoid disagreeing with those deniers, and recieving the blast of invective that normally accompanies such disagreement; but they also get to pretend that the supporters of AGW theory are arguing against a strawman. The pretence is disengenuious, and in fact many deniers do in fact claim that "hide the decline" refers to a fraudulent concealment of a decline in mean global surface temperatures as measured in the instrumental record. As to Starr's claim that Jones and Manne are "hiding the evidence", publishing the evidence, drawing attention to the discreprancy, and then discussing it in several papers, then citing those discussion in all other papers where the data is used is a funny way to hide something. In fact, in most circles that is considered drawing attention to the problem. But not, apparently, in denier circles, when the publishing, discussing, and citing is done by a climate scientists.
89712. Dikran Marsupial at 21:35 PM on 7 April 2011
       2nd law of thermodynamics contradicts greenhouse theory
       Fred@975 It seems to me that the source of the disagreement here is that you view backradiation as a separate theory, rather than as a component part of the "top of the atmosphere" explanation. AFAICS this is incorrect, it is backradiation that causes the surface to warm until equilibrium is re-established following an increase in the height of the emitting layer at the top of the atmosphere.
89713. les at 21:31 PM on 7 April 2011
       2nd law of thermodynamics contradicts greenhouse theory
       976 Staples SoD seems quite comfortable with Entropy.
89714. CBDunkerson at 21:22 PM on 7 April 2011
       A Plan for 100% Energy from Wind, Water, and Solar by 2050
       Vladimer: "The problem is that almost all of that is hypothetical." If you had actually read the article you might have noticed the part about; "we consider only options that have been demonstrated in at least pilot projects and that can be scaled up as part of a global energy system without further major technology development." Renewable energy technology does not require further development to replace most fossil fuel use. The current state of development is more than sufficient and getting better rapidly.
89715. Fred Staples at 21:16 PM on 7 April 2011
       2nd law of thermodynamics contradicts greenhouse theory
       As I posted my last contribution, I noticed that we are to be favoured by another post from SOD. I debated back radiation theories with someone I believed to be SOD in Eli Rabett’s blog, some time ago. Quoting from memory, SOD based his argument on the conservation of Energy (“where does the energy go”?) He freely admitted that, for him, entropy “never seemed real” and its formula deltaS = DeltaQ/delta T did not make sense (which, since that version is wildly wrong, is not surprising). No-one should comment on AGW (or anything else, in my opinion) without a reasonable grasp of the second law of thermodynamics. For any spontaneous transaction, anywhere in the known universe, the change in entropy must be positive. Now if a quantity of energy deltaQ leaves the atmosphere at a temperature Ta, the change in entropy is -deltaQ/Ta.If it is absorbed by the surface, at a temperature Ts, the change in entropy is +deltaQ/Ts. Now, since Ta is less than Ts (the lapse rate again), the combined change in entropy is negative, which is forbidden. If it happens on the microscopic level (vibrating molecules in a steel bar, heated at one end, or photons from a cold plate to a hot plate), it must be accompanied by a greater transfer in the conventional direction, hot to cold. It cannot be considered or analysed in isolation, which would take us immediately to a search for perpetual motion, as G and T point out at excessive length. By transferring from a hot source to a cold sink, energy becomes heat which can produce work. No net change is possible in the opposite direction without a heat engine. So to answer the question posed in the introduction, have climate scientists made an elementary mistake in explaining AGW? Of course not. Have most of the bloggers, politicians and journalists? Undoubtedly.
89716. CBDunkerson at 21:13 PM on 7 April 2011
       Arctic Ice March 2011
       Gilles: "is there any clear parameter in the past (such as the value of last minimal, or maximal extent, the amount of < X years old ice, etc..) that would be useful to predict the next minimum, and allow such predictions to be made with a significative success ?" No. None of the factors causing the ongoing trend of Arctic ice decline is consistently greater than short term weather variations. Ergo, no single such factor, nor even a combination of factors, can be used to precisely predict results in individual years. However, they can and have been used to predict the trend of the decline. Also: "do you have a physical explanation of why the arctic sea ice extent doesn't show any significative variation in the 1900-1940 period, when the average global temperature shows a variation similar , although slightly smaller, to the current one ?" Global != Arctic Arctic temperatures have risen much more in the recent warming phase than they did in the earlier part of the century. Further, as others have noted, the existing ice was much thicker in the past and thus the ice-albedo feedback effect was nowhere near as pronounced as it is now. That said, my recollection is that the perfect flat line in a few spots on that graph is due to lack of data for those years. Still, a gradual decline in Summer ice extent (i.e. the period most impacted by warming) can be seen in conjunction with the earlier warming period and a more pronounced decline with the current more pronounced Arctic warming. Finally: "so why the temperature change in the 1900-1950 period has not produced any change in the sea ice extent" As I noted, the Summer data does show a decline in the 1900-1950 period. Ignoring that in favor of the periods where warming would have less impact is essentially a return to the 'conditions have been reset' argument that you claimed you are not making.
89717. Fred Staples at 20:32 PM on 7 April 2011
       2nd law of thermodynamics contradicts greenhouse theory
       In a series of posts, I have tried to demonstrate that “higher is colder” is the only theory of AGW that does not contradict basic thermodynamics. Sadly, it is the only theory that G and T do not address. It is a top-of-atmosphere theory (where CO2 effects are not swamped by water vapour) and it depends on the existence of the lapse rate. The climate models are based on this theory, (which does not mean that it is correct, Tom) and predict mid-troposphere temperatures trends about about 20% higher than surface trends (50% higher in the tropics, where increased evaporation should produce the famous missing hotspot). To test the theory, we can look at the satellite data (from 1979) and, separately, radio-sonde data compiled by the Hadley Centre. At first sight, any debate is settled by the satellite data, which shows trends in the opposite direction to the models (wikipedia - satellite temperature measurements): Mid Troposphere : 0.52 degrees per century Lower Troposphere : 1.4 degrees per century However, the commentators cast doubt on the upper atmosphere results because they are contaminated by readings weighted from the stratosphere, which is said to have cooled (see below). A more straightforward source is the radio-sonde data from the Hadley Centre, which provides data at all levels. The trends over the satellite era, in degrees C per century, are as follows: Lower Troposphere 1.45 kilometers : 1.54 Mid Troposhere 5.56 kilometers : 1.58 Upper Troposphere 9.13 kilometers : 1.27 Lower Stratosphere 11.74 kilometers: -0.28 (not significantly different from zero) Upper Stratosphere 21 kilometers : -8.10 Has the stratosphere cooled? In the upper reaches, unquestionably, but these tenuous regions will not effect satellite readings. The lower stratosphere has not cooled significantly, but the more or less constant temperatures might mask (to some extent) warming in the troposphere as viewed by the satellites. Those whose business it is are working on this. I tested the significance of all the data (the use of second decimal places presumably shows that scientists have a sense of humour), and there is 1 chance in 18 that the trend difference between the lower and upper troposphere arose by chance, (ie from random fluctuations in the data) which is just less than the conventional 5% level. What can we conclude from this data? Warming there has certainly been but the data lends no support to any theory of causation. If I were an AGW enthusiast I would be particularly worried about the lower trend in the upper troposphere. And the satellite data would be conclusive (against “higher is colder”) were it not for the constant (ie not cooling) lower stratosphere temperatures. The data also confirms another piece of conventional sceptical wisdom. Working back from the latest data, we can ask how far we must go to detect a statistically significant period of warming. The answer, for the mid and lower troposphere, is 15 years. For the upper troposphere, 19 years.
89718. RyanStarr at 20:07 PM on 7 April 2011
       Tai Chi Temperature Reconstructions
       I derived this myself from the ljungqvist2009 data file. I used columns 64 to 71, 8 series. Unfortunately the southern hemisphere isn't represented as well as the north, but can't be ignored it is half of the globe. For each the sigma is calculated and the average of all is taken. Columns names are: 64. Lake Pallcacocha, Ecuador 65. W. Argentina 66. Subtropical Atlantic off W. Africa 67. Makapansgat Valley, S. Africa 68. SE. South Atlantic 69. Mt. Read, W. Tasmania 70. Law Dome, E. Antarctica 71. Dome C, E. Antarctica
89719. jatkeison at 19:54 PM on 7 April 2011
       Call for beta testers of the latest SkS Firefox Add-on
       I'll install it on Ubuntu 10.10 and Windows XP Professional... Well, after i get back from the Michael Mann talk tomorrow night! <LOL>
       Response: Sent and let us know how the talk goes :-)
89720. MichaelM at 19:44 PM on 7 April 2011
       Arctic Ice March 2011
       I imagine your scientific bona fides are called into question when you say things like "do you realize that most of the ice in winter is just 6 months old anyway" when you yourself provided a graph which showed that winter ice used to be 15 million sq k and dropped to 11 in the summer i.e 4 million was new ice. If the 11 million k multi-year ice was slowly being thinned by gradually increasing temps then there comes a point when it is thin enough to melt in summer allowing the sea to absorb more heat.
       Moderator Response: [Dikran Marsupial] Gilles' scientific bona fides are off-topic, please let us not feed the troll on that one.
89721. les at 19:39 PM on 7 April 2011
       Arctic Ice March 2011
       161 Gilles - I understand, at least, that you are not first language English - the phrasing at the end of post 159 is a coining of Senitor Bentsen. You can't be blamed for not spotting that. In fact I [also] have a substantial background not least of all in science and engineering. But, as with all of us here, you cannot really validate that any better than I can or will go through your CV. Your arguments do not stand up to your claims of qualification. You should really strive to fix that.
       Moderator Response: [Dikran Marsupial] Please, no more discussion of Gilles' science background, it is entirely irrellevant, and frankly just trolling.
89722. Gilles at 19:19 PM on 7 April 2011
       Arctic Ice March 2011
       les : you're just proving again your lack of perspicacity. I have 130 refereed papers, including 60 in a large scientific collaboration. Either something is wrong with you, or something is wrong with refereed papers - which is a problem for you anyway. If you only "know" scientist, or have only "friends", I do not consider you as a reliable person for judging who is a real scientist or not. 160 adelady : thank you for having the courage of proposing something - but what do you call "vast amounts of very thick ice " ? do you realize that most of the ice in winter is just 6 months old anyway, every year , so can't be "very thick"? so why the temperature change in the 1900-1950 period has not produced any change in the sea ice extent, whereas the largest change has occured only in the last decades - where strangely enough, on the opposite , temperatures haven't increased significantly since 1998 ? you seem all to say "come on, Gilles, it's obvious, the warmer it is, the more ice will melt" - but actually there is no obvious correlation on a year to year basis. I could equally argue that the melting of ice is "obviously" due to the motion of Pluto with the same data ....
       Moderator Response: [Dikran Marsupial] Your claimed status as a scientist are off-topic unless you identify yourself so that the claim can be verified. Whether your posts have values depends on their intrinsic merit, not the merit of the source. Argument from authority is a logical fallacy, and unimpressive if the authority is unverifiable, so please everybody give it a rest, and limit the discussion to the science itself. The last paragraph is obvious trolling, there is a good physical reason to expect warming to result in ice melting, there is no good physical reason for the motion of Pluto to affect the ice melt, which is why one explanation is very much more plausible than the other. In science this is known as "Occams razor", if two theories explain the observations equally well, we should prefer the more simple. In this case any theory linking Pluto to ice melt is going to be pretty complicated.
89723. JMurphy at 19:16 PM on 7 April 2011
       Has sea level rise accelerated since 1880?
       daniel maris wrote : "I take a rather simplistic view - I'll be interested when the water starts lapping over some islands. These effects are really very minimal. A few mms over decades? I mean - put a bit more cement on top of your sea wall...abandon that pontoon and build a new one...move your settlement a few feet up the hillside. These are not cataclysmic effects - no more cataclysmic than say a port getting silted up." There's plenty of information out there that shows that maybe there are lots of people who are/should be worried, despite the fact that you don't appear to be, because of the effects of that 'little' rise : 1) The impacts of sea level rise - even in the lower ranges of the current predictions - looks to be severe. Approximately ten percent of the worlds population - 600 million people - live in low lying areas in danger of being flooded. A previously released study led by John Church, shows that even a modest sea level rise of 50 centimeters will result in a major increase in the number of coastal flooding events. "Our study centered on Australia showed that coastal flooding events that today we expect only once every hundred years will happen several times a year by 2100", says John Church. 2) "According to the most recent sea-level-rise science, that's where we're heading," said lead researcher Jeremy L. Weiss, a senior research specialist in the UA's department of geosciences. "Impacts from sea-level rise could be erosion, temporary flooding and permanent inundation." The coastal municipalities the team identified had 40.5 million people living in them, according to the 2000 U.S. Census. Twenty of those cities have more than 300,000 inhabitants. 3) One often-overlooked dimension is elevation. Ten percent of the world's population lives in coastal areas that are less than 10 meters (33 feet) above sea level, reports Balk and her colleagues. Although they only comprise about 2.2 percent of the world's land area, these low-elevation coastal zones (LECZs) are home to 600 million people. In addition, about 360 million people in LECZs live in urban areas which means that more people will be exposed to hazards such as sea-level rise and storm surges—phenomena that are expected to worsen as a result of global warming. The Effects of Rising Sea Levels Although inundation by increases in mean sea level over the 21st century and beyond will be a problem for unprotected low-lying areas, the most devastating impacts are likely to be associated with changes in extreme sea levels resulting from the passage of storms (e.g., Gornitz et al., 2002), especially as more intense tropical and extra-tropical storms are expected (Meehl et al., 2007). Simulations show that future changes are likely to be spatially variable, and a high level of detail can be modelled (see also Box 11.5 in Christensen et al. (2007). IPCC As for your disdain towards silted-up ports, I think you will find that the populations who inhabited ex-ports like Miletus, Ephesus, and Great Yarmouth (and other Kentish ports), among others, would want to argue with you about your definition of "cataclysmic" as it applies to peoples' lives and livelihoods.
89724. les at 18:59 PM on 7 April 2011
       Skeptical Science in other media
       21 adelady makes some good points. Historically, the rift between religion and science (broadly speaking, lets say skeptical questioning) occurs in two situations. There are often refits: 1/ Between The Church and other sources of authority or 'truth' (be they state, science, other religions etc.) 2/ Between Fundamentalist interpretations of religious dogma and just about every thing else. The first originates, most notably, with the emergence of the Holy Roman Empire. The second is what it is and crops up within many confessional domains - e.g. there are both Christian and Muslim etc. creationists. However beyond the above, there are/have been Christian, Jewish, Muslim, Buddhist, etc. dominant societies and individuals that have strong investigative, scientific, skeptical traditions throughout history to the current day. There just is - empirically speaking - absolutely no evidence that societies with one or several dominant religions, or individuals who are confessional in general terms, cannot or do not do good science... until some political structure or ideology breaks things; And that is not unique to religions either. The dominant politics in the US has elements of both power conflict (1 above) between big industries and the output of scientific investigation; and of fundamentalist thinking (in this case constitutional fundamentalism, typified by Ron Paul etc.) The more negative religious forces are just hangers-on. In short: Being religious is neither a necessarily nor sufficient condition for doing poor science.
89725. adelady at 18:11 PM on 7 April 2011
       Human CO2 is a tiny % of CO2 emissions
       See the moderators remarks @119. Sea levels 20-25 metres higher sounds like a major impact on habitability of every coastal city I've ever heard of.
89726. adelady at 18:07 PM on 7 April 2011
       Arctic Ice March 2011
       Gilles ".... could you explain the big difference in the post-1900 behavior of these two curves ?" Off the top of my head? I'd say that looks very much as though starting the warming period with vast amounts of very thick ice is a great stabilising influence on ice extent. So influential in fact that once that particular warming period waned, it was easy for the ice to regain some, maybe not all, of the thickness invisibly lost from beneath to warmer waters.
89727. tr1ckyOne at 18:03 PM on 7 April 2011
       Human CO2 is a tiny % of CO2 emissions
       I'm not sure if my question is on-topic or not, but shouldn't we be examining what the consequences of temperature increases rather than if it's natural and within error parameters? I'd think that would be more important. How much global warming is going to affect our human existence, what its effect will be on our food chain, weather patterns, water supply...and what we can do to prevent these consequences. So even if global warming is due to natural cycles, shouldn't we do something to prevent it anyways? Can someone post some facts about earth habitability during various global temperature extremes? And what the prospects are for our habitability during these extremes. I think that would be pretty useful.
89728. adelady at 17:56 PM on 7 April 2011
       Skeptical Science in other media
       nicholas. Convert? Never in a million years. What christians like John Cook and others here can do, and none of us unbelievers can do, is to show other christians that there is no conflict between science and religion. They might say they are two separate things. Or others might say that science is one way to see more of the wonder of the created world (I suspect John might be in this group). I think you're falling for the argument (of very shrill voices) that the YE creationists represent the majority christian viewpoint. They don't. Catholics, Anglicans, Episcopalians all accept the evidence of science as shown in geology, astronomy, biology, archaeology and all the rest. Lots of people who accept science hold irrational beliefs and superstitions. Astrology, feng shui, gaia belief, ancestor worship. Focus on the science. If people want to hang onto their other beliefs at the same time, let them. Getting diverted onto arguments about "you couldn't possibly believe ..... if you accept scientific method" is a waste of breath.
89729. les at 17:31 PM on 7 April 2011
       Arctic Ice March 2011
       I note that Gilles has shown no evidence of having read the paper linked above which actually shows how to analyse for acceleration... and now we have a copy of Taminos explanation for sea level rise on site - yet he continues to shove one graph up against another and go "look, see"... 156 Gilles "But I can't prove them who I really am." No, but on discussion boards like this people tend to be judged by their deeds and words. And I echo others sentiments; I have worked with scientists, I know scientists, scientists are friend of mine. Gilles, you're no scientist.
89730. tomh at 16:45 PM on 7 April 2011
       Call for beta testers of the latest SkS Firefox Add-on
       I'll be glad to test it on three configurations: FF4 under Windows XP; FF4 under Mac OS X 10.6 (Intel); TenFourFox under Mac OS X 10.5 on PPC (TenFourFox is a branch of FF4 compiled to run on PPC-based Macs).
       Response: Sounds like you've got all bases covered. File sent, thanks!
89731. villabolo at 16:13 PM on 7 April 2011
       Has sea level rise accelerated since 1880?
       @4. daniel maris: "...I take a rather simplistic view - I'll be interested when the water starts lapping over some islands. These effects are really very minimal. A few mms over decades?" Daniel, are you forgetting that there is a time delay before large amounts of ice completely melt for any given temperature? Also, what about the 1 degree Fahrenheit rise that is in "the pipeline" for the next 30 years? That's assuming that we stop all emissions today. Since that won't happen we have to take at least a bare minimum of 450 ppm into account (still unrealistic).
89732. sgmuller at 15:38 PM on 7 April 2011
       Has sea level rise accelerated since 1880?
       How long does it take for sea level rise in the North Atalntic (from Greenland ice sheet melt) to spread worldwide? I recall a Newscientist article which suggested that it may take up to 30 years for a North Atlantic sea level rise to spread out worldwide. Sorry I don't have references but the author suggested that the world's oceans were analogous to a series of bathtubs linked by small hoses rather than a continuous ocean. Given that the Greenland ice sheet is likely to be a much larger contributor to sea level rise than antarctica ice sheets, this is a significant issue.
       Moderator Response: [DB] The effects of GIS melt on sea levels is indeed discussed by the New Scientist article on the Stammer JGR paper (discussed here). Effects of a collapse of the WAIS are discussed here. Keep in mind that sea level rise is continuous (globally averaging about 3 mm per year currently, but projected to rise significantly with the expected melt). Hansen 2011 discusses scenarios under which 5 meters of SLR can be expected globally by 2100, due to non-linear ice sheet decomposition.
89733. Gilles at 15:04 PM on 7 April 2011
       Arctic Ice March 2011
       another related question : do you have a physical explanation of why the arctic sea ice extent doesn't show any significative variation in the 1900-1940 period, when the average global temperature shows a variation similar , although slightly smaller, to the current one ? and when, noticeably , proxies data show the maximal variation ? are boreal trees much more sensitive to some kind of temperatures that sea ice doesn't feel, and reciprocally? on other word, could you explain the big difference in the post-1900 behavior of these two curves ? and this one ??
89734. Gilles at 14:53 PM on 7 April 2011
       Arctic Ice March 2011
       an answer to Tom : #152 well actually it seems that after dismissing totally the fact that we need historical records (much longer than T ) to interpret a variation over some give period T , you precisely use this method to validate the claim that you are doing - that the variation is indeed significative when compared with the past. But it was exactly what I was saying. It is not a question of fitting by any number of components, it is a question of comparing the amplitude of variation with a known noise - and to know the noise you have to measure it over a long enough period. Now it's unfortunate that the noise you're showing doesn't seem to be very accurately determined, since , "Blue shading indicates the pre-satellite era; data then is less reliable. In particular, the near-constant level extent in Autumn up to 1940 reflects lack of data rather than a real lack of variation." But there is fortunately a way of quantifying this inaccuracy : it is called "error bars" - do you have an idea of error bars associated with the pre-1940 measurements ?
89735. Gilles at 14:44 PM on 7 April 2011
       Arctic Ice March 2011
       I sincerely thank all people who care so much about my mental mind and can elaborate so deep thoughts about who I am, what are my real scientific capabilities , and what are my personal motivations. Unfortunately , as they don't know me personally, nor my life, or my personal opinions, they don't have the possibility to test their scientific theories by comparing them with reality. But obviously this doesn't change much their faith in their own beliefs. I'm the only one to be able to compare their judgements with my reality - and believe me or not, this is unfortunately not in favor of their perspicacity. But I can't prove them who I really am. Please notice that I wasn't claiming anything about the state of the ice in May , I was just asking for your opinion. Thanks to all who answers properly : no , there can be a lot of differences even if some parameters are equal. Well, that's what I would call a "memory", or more technically, a "hysteresis" . So let us admit there is such "memory" : my second question is : is there any clear parameter in the past (such as the value of last minimal, or maximal extent, the amount of < X years old ice, etc..) that would be useful to predict the next minimum, and allow such predictions to be made with a significative success ? (I stress again that I am not claiming anything, I just like to benefit from your deep scientific knowledge).
89736. Vladimer K at 14:32 PM on 7 April 2011
       A Plan for 100% Energy from Wind, Water, and Solar by 2050
       The problem is that almost all of that is hypothetical. That is, we lack the technology to do that now. Smart grids may exist in time. We may be able to mass produce dams. We may be able to jack up the capabilities of solar and wind. We may have hydrogen cells. Even if we do get all of those, it may not be possible to even start implementing this until 2030 or further. Unless we want to cast everything to the wind and hope we can do it, it's reasonable to suggest building new nuclear plants until then. And equally reasonable that we let them live their lives out before decommissioning them. And what will we replace them with? Well, since we're talking hypotheticals, we could replace them with pebble-bed reactors (due out 2015), Generation IV reactors (2021), or even fusion reactors, due out by 2040, a decade before we rely entirely on renewables. This WWS future simply won't materialize.
89737. RyanStarr at 14:28 PM on 7 April 2011
       Muller Misinformation #1: confusing Mike's trick with hide the decline
       "Phil Jones' email is often cited as evidence of an attempt to "hide the decline in global temperatures". This is incorrect." This is a red herring. Skeptics don't argue that at all, they understand exactly what was meant by "hide the decline" and they understand why it is problematic. Giving a flaw in the method a formal name e.g. "divergence problem" and hiding the evidence of it does not excuse Phil/Manne et al, quite the contrary. Also Muller's alledged confusion now has no bearing on events which occurred in a past decade. The author commits the same sin he accuses Muller of when he conflates these unrelated matters.
89738. KeenOn350 at 14:27 PM on 7 April 2011
       Call for beta testers of the latest SkS Firefox Add-on
       Be glad to test on 3.6 & 4. also DaveW
       Response: Thanks, Dave, file sent.
89739. Daniel Bailey at 14:23 PM on 7 April 2011
       Upcoming book: Climate Change Denial by Haydn Washington and John Cook
       @ scaddenp A safe assumption. h pierce also has posted here at SkS under the name Harol Pierce Jr (probably because another user had Harold Pierce Jr). The Yooper
89740. ribwoods at 13:57 PM on 7 April 2011
       Call for beta testers of the latest SkS Firefox Add-on
       I can test it on both 3.6.16 and 4.0
       Response: That would be great. Just sent you the file.
89741. scaddenp at 13:54 PM on 7 April 2011
       Upcoming book: Climate Change Denial by Haydn Washington and John Cook
       I wonder if this is the same harold pierce jnr, (see the comment here) who thinks that GHE has been falsified by the temperature data in Death Valley (speaking of pie-in-the-sky nonsense).
89742. Marcus at 13:17 PM on 7 April 2011
       Upcoming book: Climate Change Denial by Haydn Washington and John Cook
       "Not possible. I am organic chemist and quite well aware of this info you guys mention" Ah, that explains it-no doubt you *work* for the Oil Industry, & so your mantra is nothing more than wishful thinking. The fact is that several research facilities-including MIT-have done successful pilot trials for the production of bio-fuels, from algal biomass, that is cost competitive with regular oil. That equation is only going to get better as oil prices continue to increase. "Wouldn't you really like to have a bright red Ford Mustang Conv. with a big honkin' 5 L V-8?" Personally, I'd rather have a vehicle that gets me reliably & cheaply from point A to point B-which is why I use Mass Transit on a regular basis. Still, I've always been of the view that people who use gas-guzzling muscle cars are just.....ahem, compensating for something ;-).
89743. Tom Curtis at 13:12 PM on 7 April 2011
       Learning from the Climate Hearing
       johnd, I believe Professor Flannery may be the "best available" at least in part because of his high public profile. Personally, I blame the politicians for the parlous state of the climate debate in Australia. In particular, when Abbott started his ... spiel about "Great Big Tax", Rudd should have had a press conference on a bleached section of the Great Barrier Reef, and discuss the CSIRO finding that with a 2-3 degree C increase in temperature, "97% of the Great Barrier Reef is bleached every year", and that with a 3-4 degree C increase, there is "Catastrophic mortality of coral species annually", "95% decrease in distribution of Great Barrier Reef species", and "65% loss of Great Barrier Reef species in the Cairns region". Pointing out that 2 degrees C is the target of the international community, and that 4 degrees C is likely to be the minimum increase with BAU might help drive the point home. The fact is, in making their various policies, the politicians of the world are gambling that 97% of climate scientists are significantly in error. You have the Republicans (and Abbots) who are betting the scientists are almost completely wrong; and the Democrats (and Guilards) who are betting they are right about the prospects, but that they are substantially over estimating the impacts. Unfortunately the stakes they are using is our future. For Australian politicians, the most visible (but not the largest) portion of their stake is the Great Barrier Reef. Abbot is betting the survival of the Reef on Andrew Bolt knowing more about climate change than do the scientists of the CSRIO. It is not a bet I am sanguine about.
89744. Nicholas Christie-Blick at 13:00 PM on 7 April 2011
       Skeptical Science in other media
       In response to 'adelady' (comment #16): Everyone has to figure it out for him/herself. Attempting to convert people from their religious beliefs is pretty much a waste of time. It remains the case that much of what folk believe is in fact not consistent with science. And that is among the reasons it has proven difficult in the United States in particular to convey some scientific results to the general public. Climate change and evolution are the most obvious examples.
89745. BeamMeUp at 12:56 PM on 7 April 2011
       Call for beta testers of the latest SkS Firefox Add-on
       Is the upgrade compatible with FireFox 4? If so I would be happy to test it
       Response: Does it work on FF4? It should do but hopefully you can tell us. I've just emailed you the file :-)
89746. Tom Curtis at 12:50 PM on 7 April 2011
       Arctic Ice March 2011
       Ken Lambert @153: Answered! Relevant point for this thread: I did not just calculate incoming flux, I also referred you to Flanner who had calculated a change in forcing. In fact, I strongly suggest you use Flanner's result if you wish to make any argument about the inconsequential nature of the ice albedo feedback that is relevant to this thread.
89747. Tom Curtis at 12:43 PM on 7 April 2011
       A Flanner in the Works for Snow and Ice
       Thankyou mc. Ken Lambert, the point of calculating the incoming energy was because it is easy to calculate a reasonable approximation of that figure. That reasonable approximation was sufficient to refute your argument about the inconsequential nature of reduced sea ice extent in the arctic on the arctic. On the other hand, while preferable, it is very difficult to calculate change in outgoing energy. Not only is there the change in temperature to consider (which is different for different seasons), but there is also the change in albedo/emissivity between ice and water, and the change in albedo of ice (because snow free ice has a much lower albedo than snow covered ice, and increased air temperatures often lead to snow free ice). Indeed, to be complete I would also have liked to include the change in heat carried to the ocean depths by the thermo-haline conveyor, which is also a factor. You are apparently arguing that because I did not calculate this very complicated factor (although I did refer you to Flanner, who did), I should not have mentioned the simpler but easily calculated factor of change in incoming flux. Frankly, the implied dictum that you should only present some relevant information if you can present all relevant information is nonsense. What is more, it not one you adhere to, for if you had, you would not have made an argument based solely on the minimal relevant information of relative surface area of the arctic to the globe.
89748. johnd at 12:42 PM on 7 April 2011
       Learning from the Climate Hearing
       Agnostic at 11:52 AM, as is the case in almost every field, those who hold the technical expertise, are far more often than not, not sufficiently skilled to effectively articulate that knowledge to a broader audience. Thus it matters not whether the person who is appointed to undertake that role has the same qualifications or not, but rather whether he can accurately interpret and convey that knowledge to the intended audience. It is very simple, if such anointed person is deemed to effectively fulfill that role by those who appointed him, and by those whose knowledge he is presenting, then his word is as good as those he represents. If he is deemed unworthy, then he should be replaced. In the private sector, there are generally no if's and buts, either they fly majestically or are grounded. Fortunately for Professor Flannery, those who appointed him have been very clear in putting all their faith in him being the best available, something that I expect many see as a fact.
89749. Tom Curtis at 11:58 AM on 7 April 2011
       Has sea level rise accelerated since 1880?
       daniel maris @4, while I agree that the prospective sea level rises over the coming century could be handled very comfortably by advanced economies, I believe you are being far to sanguine. During the Eemian epoch, the last interglacial, the mean global surface temperature was 1 to 2 degrees warmer than the those in the middle of the 20th century, ie, 0.3 to 1.3 degrees warmer than today, and around the temperature target currently muted for stabilizing CO2. During the Eemian, the sea level was 4 to 6 meters higher than at present - sufficiently high to turn Scandinavia into an island. So that is the sea level, at minimum, we are heading for given sufficient time. Of course, glacial melt, the primary source of the sea level rise, is slow. Assuming it rises to the average rate during the last great glacial melt, ie, the end of the last glaciation, then sea levels will eventually be rising at about 15 mm per year, or 1.5 meters per century. It will take a while to ramp up to that, so lets predict about a 1 meter sea rise by 2110. I believe that to be a reasonable estimate. Three things should be noted about that: 1) Even with a 1 meter sea rise, the costs of responding to that, either by building sea walls, or by abandoning properties and shifting to new locations, will be less than the cost of eliminating fossil fuel use from our economies. So if that were the only cost of global warming, perhaps we would be better with BAU. But it is not the only cost - indeed it is probably the smallest prospective cost of global warming, so BAU is not a sensible strategy. 2) That rate of sea level rise would not stop in 2110, but in fact continue of for another two or three centuries after that. Just factoring in the short term costs is poor planning, particularly when the long term costs will involve either placing a 10 meter plus sea wall around most of the coast line of most nations, or the loss of very significant areas of arable land. 3) This grim if very slow impact is more or less what we are committed to already. If we go to zero carbon economies by 2050, we are already looking at 4 to 6 meter long term sea level rises. If we continue at BAU, the rise is likely to be much larger. Finally, none of this should detract from muoncounter's very excellent response. Although responding to sea level rise is very doable, it involves large scale capital works and/or land resumptions. In other words, it is an expensive project whose benefits will not be fully felt until 20 to 30 years after the event. Governments don't do that sort of project well, so we are likely to experience the cost of sea level rise in increased damage and financial costs from storms. And if we do it that way, the costs will be significantly greater than the costs of eliminating fossil fuel use from our economies.
89750. Riduna at 11:52 AM on 7 April 2011
       Learning from the Climate Hearing
       My comment refers to climate scientists. Professor Flannery though very well informed is not a climate scientist, and his recent appointment has yet to demonstrate any success in public education, let alone education of those who govern us. Like you, I wish him every success in his February, 2011 appointment as Climate Commissioner. What I am critical of is the role of climate scientists over the past 3-5 years in providing information to our politicians – and of politicians for not seeking such advice and the gullibility of those who accept the views of the likes of Plimer in preference to the findings of climate science.

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