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Comments 123601 to 123650:

123601. kwinters79 at 10:36 AM on 25 February 2010
        Misinterpreting a retraction of rising sea level predictions
        #18 Berényi Péter, You're claiming you can eye-ball a single tide guage and determine if the global sea-level rise is accelerating or decelerating? Or even a few individual tide guages? That's amazing! In #7 you wrote: "The 190 cm figure is baseless, Vermeer & Rahmstorf 2009 should be retracted as well." I'm sure it will, if (and only if) someone comes along to point out an actual flaw in their methodology or conclusions. But eye-balling individual tide guages doesn't accomplish that.
123602. Berényi Péter at 10:28 AM on 25 February 2010
        Misinterpreting a retraction of rising sea level predictions
        #15 shdwsnlite at 09:26 AM on 25 February, 2010: "The more input, the more eyes on a problem the more self correcting for errors" Agreed. This is what I am trying to do here. Unfortunately most guys can only quote authoritative sources instead of having their eyes on the problem itself. I am prone to err as anyone, correction is welcome. However, in this topic I have not seen a valid one yet.
123603. Berényi Péter at 10:17 AM on 25 February 2010
        Misinterpreting a retraction of rising sea level predictions
        #10 Jeff Freymueller at 07:39 AM on 25 February, 2010: "Vermeer and Rahmstorf's post at RealClimate last August, which appears to be where they spotted the error" OK. In that post they say: "To constrain the value of a – which dominates the 21st Century projections — one needs to look at the “new rise”. How much has sea level rise accelerated over the 20th Century, in response to rising temperatures? That determines how much it will accelerate in future when warming continues" http://www.realclimate.org/index.php/archives/2009/08/ups-and-downs-of-sea-level-projections/ Sounds reasonable. Let's see. PSMSL (Permanent Service for Mean Sea Level) tide gauge data from Proudman Oceanographic Laboratory http://www.pol.ac.uk/psmsl/datainfo/ http://www.pol.ac.uk/psmsl/psmsl_individual_stations.html New York tide gauge http://www.pol.ac.uk/psmsl/pubi/rlr.annual.plots/960121.gif http://www.pol.ac.uk/psmsl/pubi/rlr.annual.data/960121.rlrdata No 20th century acceleration at New York tide gauge. Not a bit. Some deceleration, if anything. If global sea level rise is accelerating nevertheless, we can conclude that New York is accelerating upwards on a slightly faster rate. Odd enough. There are quite some tide gauges in PSMSL with long records. Would anyone set about computing acceleration for each one? It is not difficult, just time consuming. BTW, acceleration should be more precise than average rate of rise, since crustal slabs are not particularly brisk.
123604. Tom Dayton at 09:58 AM on 25 February 2010
        Misinterpreting a retraction of rising sea level predictions
        shdwsnlite, you sure sound like a scientist! I am one, and I agree with you completely.
123605. shdwsnlite at 09:26 AM on 25 February 2010
        Misinterpreting a retraction of rising sea level predictions
        Let me start off on my first post here and say I am not a scientist and I admit that reading through these posts makes my brain hurt sometimes. I am trying to learn though. I do have a question for Berényi Péter...in your self sufficiency of logic and truth suppose an error creeps in to your work which results in your conclusion being in error. You review your work following the same line of thought and as the process is unchanged then the error remains. In your eyes then your result is "Truth" but ultimately it is false. That is the benefit and need of reviewers and the community at large. The more input, the more eyes on a problem the more self correcting for errors.
123606. Tom Dayton at 08:55 AM on 25 February 2010
        Have American Thinker disproven global warming?
        Aha, Pierre-Normand! It was you that was that itch in the back of my brain while I was typing! I'm glad you wrote your version, because it is more technically accurate than mine. (I'm not technical.)
123607. Pierre-Normand at 08:52 AM on 25 February 2010
        Have American Thinker disproven global warming?
        That's funny; it seems Tom Dayton and I said exactly the same thing at the same time, though in different words. OLR is the (reduced) flow just in wake of the rock. Total whortwave emitted to space is the total water flow downstream from the leaky 'rock-dam'. Conservation of mass dictates that this flow is equal to the flow (non-reflected solar input) upstream from the dam, except in the non-steady state where the water level rises upstream of the dam (heat accumulates and temperature therefore climbs below the atmospheric greenhouse-blanket)
123608. Berényi Péter at 08:50 AM on 25 February 2010
        Misinterpreting a retraction of rising sea level predictions
        #8 Albatross at 06:51 AM on 25 February, 2010: "If you can convince the reviewers and scientific community that your analysis and projections are both superior and reliable, then I will accept your lower estimate until such time as newer evidence suggests otherwise" Man, try to think for yourself. It is not so difficult. Of course I don't have any estimate of my own. I just put two estimates side by side, one from Vermeer & Rahmstorf, from Siddall's retraction letter the other one. I care neither for reviewers nor the scientific community, but I do care for logic & truth. Appealing to authority is NOT the way science is done. Not even scientific authority is competent in this respect. As long as you are able to understand stuff, you are self sufficient.
123609. Jeff Freymueller at 08:42 AM on 25 February 2010
        Misinterpreting a retraction of rising sea level predictions
        #12 joseph, I did simplify it considerably (maybe too much). Siddall et al. defined the equilibrium sea level in terms of the inverse hyperbolic sine of a quantity that was linear in temperature. The modeled sea level then follows a differential equation of which the equilibrium sea level as a function of time is the inhomogeneous part. dhogaza's explanation (#11) is better than mine was.
123610. Cowboy at 08:39 AM on 25 February 2010
        What would happen if the sun fell to Maunder Minimum levels?
        "Cowboy @ 86, If you shared a bank account with Mrs Cowboy and you put in $1000 a month, and each month you found the balance rose by only $500 a month, you would know that Mrs Cowboy was spending $500 more a month than however much she were putting in. You would not need to tag all of the $1 bills as being "hers" or "yours" to know that she were a net drain on your bank account." However, if I was ESTIMATING that I was putting in $1000 a month when it could actually vary between $500 and $1500, and if she was randomly putting in anywhere between $10000 and $20000 a month, and we did not reconcile to actual bills and bank fees for each of us that month, then having $500 at the end of any particular month would be meaningless with respect to whether I was actually on net, contributing to overall wealth or debt. Accounting can be meaningless for taking action without actual, exact transaction receipts, account numbers (tags) and a ledger over a statistically significant period of time.
123611. Pierre-Normand at 08:35 AM on 25 February 2010
        Have American Thinker disproven global warming?
        It is my understanding that OLR at the top of atmosphere mustn't be confused with the total long-wave radiation emitted by the whole Earth+atmosphere system. Conservation of energy dicrates that under steady state conditions the latter rather than the former must be equal to incoming solar radiation (minus reflected shortwave energy). So, when Ramanathan speaks of a reduction of OLR, he is not speaking of a reduction in the total longwave emitted to space that satellites measure. His Figure 1 also make that clear. Total longwave emissions include longwave from the surface that the atmosphere is transparent to. When greenhouse gasses trap more longwave radiation coming from below the top of atmosphere, then less OLR is emitted from there. But this is compensated when the surface heats up and more longwave from the surface escape through the 10-micron window (roughly). Under steady CO2 increase, as occurs now, steady state isn't achieved and there is a net energy imbalance of 4W/m^2 (also caused by water vapor feedback). This is much smaller than the total OLR reduction Ramanathan speaks of. Those are apples and oranges. Under steady state (no more CO2 variations), the 4W/m^2 imbalance would disappear but the constant large OLR reduction would keep the Earth from cooling back.
123612. Tom Dayton at 08:35 AM on 25 February 2010
        Have American Thinker disproven global warming?
        Gary, Following up Doug's comment: You (Gary) seem to be assuming there is a rule requiring constancy of the proportion of IR leaking out past CO2 in the CO2-absorbing wavelengths, versus leaking out in other wavelengths. Or maybe just that the amount leaking out in other wavelengths must remain constant while the amount leaking out in CO2-absorbing wavelengths decreases. There are no such rules. CO2 molecules bang into other molecules (both gas- and non-gas molecules), thereby transferring some of their energy. Also, CO2 molecules emit IR in directions that get it absorbed by non-gas molecules. All those other, non-CO2, energy-recipient molecules then go about their business, doing whatever they do with that energy, including transferring it to yet other molecules gaseous and non-gaseous. That energy is perfectly capable of eventually turning into IR in wavelengths that are not absorbed by CO2. Some of that IR will head out to space, unimpeded by CO2. In that way, IR that is blocked by CO2 can eventually work its way around the CO2 roadblock. Analogy: In a small stream (outgoing IR), put in the middle a rock (CO2) that is short enough to allow water to flow over it (IR leaking through CO2), but tall enough to noticeably impede the flow (IR absorbed by CO2). Ensure that the rock is not as wide as the entire stream (CO2 does not absorb all wavelengths of IR). Consequence 1: The amount of water flowing over the rock is less than the amount of water that was flowing in that exact rock-occupied area before the rock was there. Consequence 2: More water is flowing through the stream on either side of the rock. A second misconception seems to be that the only energy trying to escape from Earth at any given moment is the energy that came in from the Sun the moment before. The misconceived argument seems to be that consequently the amount of energy escaping cannot be larger than the amount of energy that came in literally moments before. But in fact, the amount of energy trying to escape depends on the amount of energy (well, heat energy--temperature) that is currently residing in the Earth's system. That resident amount of energy increases by accumulation due to blockage by CO2. In the stream analogy: If the rock in the middle is wide enough and tall enough, water will accumulate behind the rock. If the rock is really tall and nearly as wide as the stream, water will accumulate despite the increased flow at the edges. If you plop down a tall enough rock initially, or quickly create an equivalent pile of little rocks by plopping them down one at a time really fast, water will accumulate before the flow on the edges increases. That mass of accumulated water, not just the water coming from upstream, is what is now driving the amount of water flowing around the edges. So there is a lag between the accumulation and the increased edge flow. The exact consequences of how much water accumulates, how much flow increases at the edges, and how much flows over the rock, depends entirely and thoroughly on the exact details of the rock's height and width, the amount of water coming down the stream toward the rock, the obstructions at the edges, and so on. It gets even more complicated if you continually increase the height of your little dam by adding pebbles on top of it. In the Earth's system, the same things happen. The exact consequences--how much energy leaks out on either side of the CO2-absorbing wavelength bands--depend on the exact details of how much energy is coming in from the Sun, how fast CO2 is increasing, and so on. The bottom line is that it is perfectly feasible to have simultaneously, increased energy accumulation, increased outgoing energy at non-CO2 wavelengths, and decreased outgoing energy at CO2 wavelengths.
123613. johnd at 08:13 AM on 25 February 2010
        The Dunning-Kruger effect and the climate debate
        The Dunning-Kruger effect is in fact a byproduct of the Peter Principle. That is, a person continually moves higher until they reach a level that is beyond their level of competency.
123614. joseph449008 at 08:01 AM on 25 February 2010
        Misinterpreting a retraction of rising sea level predictions
        

        In the paper, they modeled sea level as being a function of a*dT+b (they used a different notation; this matches Vermeer and Rahmstorf in RealClimate and is simpler. dT is change in temperature).

        That sounds way too simplistic. I haven't taken the time to read the relevant papers, though. A model of SLR should consider ice melt and thermal expansion separately. Thermal expansion is non-linear. I was looking at density of water given its temperature and salinity, and a quadratic equation fits it quite well. It's complicated to do an ocean estimate because the temperature of ocean water varies with depth, and modeling this seems non-trivial by itself. Ice melt looks even more complicated. You can probably come up with a model for 'equilibrium' ice volume. But then the speed of ice melt is tricky. This would have to depend on the difference between the current ice volume and the equilibrium ice volume, times the surface area of heat transfer.
123615. dhogaza at 08:00 AM on 25 February 2010
        Misinterpreting a retraction of rising sea level predictions
        Berényi Péter sez:

        Siddall's retraction letter says: "we overlooked that the simulations of the twentieth and twenty-first centuries are sensitive to this time step, which led to an overestimation of the sea-level response to warming in the simulations for these centuries

        He's assuming that "response" means "sea level rise". That's not the fact. From Rahmstorf's original criticism at Real Climate, which eventually led to the correspondance which led to Siddal retracting the paper:

        Siddall et al. in contrast find a time scale of 2900 years, but introduce a non-linearity in the equilibrium response of sea level to temperature (see their curve in Fig. 1 and footnote 3 below): it flattens off strongly for warm temperatures.

        The response which is overestimated is this flattening of sea level rise, not sea level rise itself. Remove that overestimated flattening and the sea level rise estimates ... rise! Here's more of Rahmstorf's RC note on this:

        The reason for both the long time scale and the shape of their equilibrium curve is that this curve is dominated by ice volume changes. The flattening at the warm end is because sea level has little scope to rise much further once the Earth has run out of ice. However, their model is constructed so that this equilibrium curve determines the rate of sea level rise right from the beginning of melting, when the shortage of ice arising later should not play a role yet. Hence, we consider this nonlinearity, which is partly responsible for the lower future projections compared to R07, physically unrealistic. In contrast, there are some good reasons for the assumption of linearity (see below).

        Note that the retraction thanks Vermeer and Rahmstorf for bringiing the overestimation (of flattening) to their attention, so Siddal at least is convinced they're right. Berényi Péter, why did you assume "response" meant "sea level rise"? It's a reasonable guess, but you don't have to guess, you know, you can always read instead.
123616. Jeff Freymueller at 07:39 AM on 25 February 2010
        Misinterpreting a retraction of rising sea level predictions
        #7 Berényi Péter, it helps to read the Siddall paper, and also Vermeer and Rahmstorf's post at RealClimate last August, which appears to be where they spotted the error (especially check the update just before the footnotes): http://www.realclimate.org/index.php/archives/2009/08/ups-and-downs-of-sea-level-projections/ In the paper, they modeled sea level as being a function of a*dT+b (they used a different notation; this matches Vermeer and Rahmstorf in RealClimate and is simpler. dT is change in temperature). The a and b are determined empirically by fitting the data. Their error caused them to get incorrect estimates for both a and b. Their retraction mentions only the effect on a. If you correct the error in their code, then their model no longer fits 20th century sea level rise (it underpredicts it), so its prediction for the 21st century obviously can't be trusted. If you increased b so that their model fits 20th century rise, then you would get a larger 21st century prediction. This might mean that you can't model both post-LGM and 20th century sea level change with the same a and b. (They mention a second error, and I don't know what effect that has, but it really doesn't matter because the entire result needs to be thrown away and redone). Or better yet, revert back to Rahmstorf's 2007 paper or to Grinsted et al. (2009), both of which lack errors, and fit the historical data. These papers predict higher future rates, by the way. I have not looked at Vermeer and Rahmstorf (2009), just downloaded it but don't have time to read it now. By the way, your statement 2 is based on your own misinterpretation (jumping to conclusions). So your final argument is meaningless.
123617. Dikran Marsupial at 07:34 AM on 25 February 2010
        What would happen if the sun fell to Maunder Minimum levels?
        Cowboy @ 86, If you shared a bank account with Mrs Cowboy and you put in $1000 a month, and each month you found the balance rose by only $500 a month, you would know that Mrs Cowboy was spending $500 more a month than however much she were putting in. You would not need to tag all of the $1 bills as being "hers" or "yours" to know that she were a net drain on your bank account. Likewise the "mass balance" argument holds without having to "tag" any of the CO2. Do read the webpage by Ferdinand Englebeen on CO2 measurements linked by Tom @ 87, it really is an excellent resource (it includes an example similar to the above).
123618. Doug Bostrom at 07:19 AM on 25 February 2010
        Have American Thinker disproven global warming?
        garythompson at 06:04 AM on 25 February, 2010 Gary, I think you're getting a bit lost trying to deal with comments while still leaving John's issues unaddressed. Could you go through John's remarks on your article point-by-point here, just so everybody's on the same page? Also, you should probably correct this sentence in the portion of your article where you discuss Lindzen & Choi 2009: "In the paper, the data showed that OLR increased when sea surface temperatures increased, so this is in direct contradiction to the AGW hypothesis that less OLR should be emitted since more CO2 is absorbing it and warming the planet." That's not really a sound conclusion, first because OLR increases in model predictions, secondly because Lindzen & Choi used undifferentiated OLR wavelengths thus making it impossible to discern C02 effects on the overall radiation, meaning you can't form a conclusion about C02 from their paper.
123619. tobyjoyce at 07:15 AM on 25 February 2010
        Have American Thinker disproven global warming?
        @garythompson, I think you have shifted ground, but are not really getting anywhere. Quick explanation from www.realclimate.org: "The way the greenhouse effect really works is that adding CO2 reduces the infrared out the top of the atmosphere, which means the planet receives more solar energy than it is getting rid of as infrared out the top. The only way to bring the system back into balance is for the whole troposphere to warm up. It is the corresponding warming of the low level air that drags the surface temperature along with it ..... " Ok, so we would expect a reduction in OLR over the absorption CO2 range. It seems to be that is visible in ALL the papers under discussion. There is also excellent agreement between observations and the models. Let me draw your attention to Fig. 5 of the Griggs & Herries (1996) paper - this also plots the differences, but bands of statistical significance from 0 are marked with vertical grey bars. You can see a good collection around the 700-800 cm^-1 (CO2)region. This seems to me to put paid to the idea that the 1997 & 1970 observations are the same. Your fallback position is that the base models are somehow mistaken. As I pointed out, the models agree with the observations. You agree with the observations, so how can you challenge the models? Incidentally, climatology could not proceed without models, not could a lot of physical science (astrophysics, nuclear physics, to name two branches). Remember the old adage of the philosophy of science "All observations are theory-laden"? You need to toss aside your ideological blinkers. I agree with Ricardo that "Your ending comment in the AT piece is thereby entirely unwarranted." The only fallback seems to be Lindzen & Choi (2009) but that has already been thoroughly critiqued elsewhere http://www.realclimate.org/index.php/archives/2010/01/lindzen-and-choi-unraveled/
123620. Tom Dayton at 07:08 AM on 25 February 2010
        What would happen if the sun fell to Maunder Minimum levels?
        Cowboy, you wrote "...show me that there is a 'tag' on anthropogenic CO2 to distinguish it from environmental CO2, and that there is a global-wide sampling using those tags...." Okay: The CO2 Measurements page has detailed explanations and links. Do be sure to click on the links, because that page is only a summary.
123621. joseph449008 at 07:00 AM on 25 February 2010
        Misinterpreting a retraction of rising sea level predictions
        

        This is the amount of warming expected for some of the lower emission scenarios. At that time of the last interglacial, sea levels were at least 6 metres higher than present levels. So while we expect sea levels to rise up to 2 metres by 2100, they will continue to rise afterwards to at least 6 metres.

        It's likely more than 6 meters. Sea level changes due to ice melt are very slow to materialize, and the last interglacial was relatively short-lived.
        Response: Good point. Kopp found it very likely (95% probability) that in the last interglacial, sea levels were at least 6.6 metres higher than today. It's likely (67% probability) that sea levels exceeded 8 metres (Kopp 2009). Note that temperatures during the last interglacial were around 2 degrees warmer than now. This is the amount of warming expected for some of the lower emission scenarios. This is important to realise when you compare current emissions to the IPCC scenarios. I will be posting about that later today (if time permits).
123622. Albatross at 06:51 AM on 25 February 2010
        Misinterpreting a retraction of rising sea level predictions
        Re # 7: "The 190 cm figure is baseless, Vermeer & Rahmstorf 2009 should be retracted as well." If you are so confident in your science and analysis (doubtful if you have done any) then please submit a comment/rebuttal to PNAS requesting a retraction of Vermeer and Rahmstorf, or even better, submit a paper describing your own data, methodology and analysis and conclusions. If you can convince the reviewers and scientific community that your analysis and projections are both superior and reliable, then I will accept your lower estimate until such time as newer evidence suggests otherwise.
123623. Jesse Fell at 06:48 AM on 25 February 2010
        Have American Thinker disproven global warming?
        Gary, I'm not sure I agree with you (I'm huffing and puffing to catch up with all you heavy weights), but I want to thank you for discussing this issue like a gentleman. If only more blogs about this critical topic were conducted in this grown-up style!
123624. Cowboy at 06:30 AM on 25 February 2010
        What would happen if the sun fell to Maunder Minimum levels?
        "The argument that the rise in CO2 is anthropogenic doesn't rely solely on correlations, a simple piece of accountancy is enough to verify that it is true. The annual increase in atmospheric carbon is about half the annual emissions (fossil fuel + land use), and the remaining carbon has to go somewhere. This excess carbon must be being taken up by the natural environment (oceans + terrestrial biosphere) somewhere, which proves that the natural environment is a net sink (over a full annual cycle)." I'll consider that at least in part if you can show me that there is a 'tag' on anthropogenic CO2 to distinguish it from environmental CO2, and that there is global-wide sampling using those tags that shows CO2 levels by source that is statistically significant at a high degree of certainty. Otherwise, I'm afraid, it sounds like a premise based on what is essentially an assumption... And by the way, we will need those tags to differentiate between 'natural' environment vs environment impacted by mankind for it to be at all meaningful. Without differentiation between fuel generated CO2 and 'residual' CO2 due to mankind's impact on CO2 sinks, I don't see how your alleged equilibrium shows anything. In that differentiation between 'natural' environment vs environment impacted by mankind you will, of course, need a control rather than relying on assumptions... good luck with that...
123625. Berényi Péter at 06:19 AM on 25 February 2010
        Misinterpreting a retraction of rising sea level predictions
        Global sea level linked to global temperature http://www.pnas.org/content/early/2009/12/04/0907765106.full.pdf Vermeer & Rahmstorf 2009 write: "When applied to observed data of sea level and temperature for 1880-2000, and taking into account known anthropogenic hydrologic contributions to sea level, the correlation is >0.99, explaining 98% of the variance" Unfortunately it does not make sense. Since observed sea level data are taken from IPCC AR4 WG1 where twentieth century sea level rise is estimated to be 14±10 cm (note the wide error margin), a 0.99 correlation during calibration phase is meaningless for a model with built-in exponential behavior. The 190 cm figure is baseless, Vermeer & Rahmstorf 2009 should be retracted as well. Even more important. Contrary to your statement "The low sea level rise is found to be in error. While some are spinning this result to imply no sea level rise, in actuality it increases our confidence in high sea level rise" Siddall's retraction letter says: "we overlooked that the simulations of the twentieth and twenty-first centuries are sensitive to this time step, which led to an overestimation of the sea-level response to warming in the simulations for these centuries" http://www.nature.com/ngeo/journal/vaop/ncurrent/full/ngeo780.html Overestimation. The plain meaning is that the 82 cm figure is too large, even for the worst model scenario. We have two statements: 1. Sea level rise during 21st century is 75-190 cm 2. 7-82 cm is an overestimation They are extremely hard to be seen as strengthening each other.
123626. garythompson at 06:04 AM on 25 February 2010
        Have American Thinker disproven global warming?
        the point i was trying to raise was - why do we need to correct for water vapor and surface temperatures when there are statements in peer reviewed papers that we don't need to do this in order to see the reduction in OLR associated with CO2 absorption? an example - according to the paper by Ramanathan entitled "Trace-Gas Greenhouse Effect and Global Warming" (http://www-ramanathan.ucsd.edu/RamAmbio.pdf), the author states on page 3 (which is really labeled page 189 since it was in a larger journal i guess) under the section Anthropogenic Enhancement of the Greenhouse Effect - "an increase in greenhouse gas such as CO2 will lead to a further reduction in OLR." notice there is no clarifying statement about having to use model simulated graphs to 'correct' for surface temperatures and water vapor before seeing that OLR reduction. and in the paragraph right above that the author states - "since the emission increases with temperature, the absorbed energy is much larger than the emitted energy, leading to a net trapping of longwave photons in the atmosphere." here the author stated clearly that even taking into account higher emissions from warmer surfaces, the net will still be a reduction. The Griggs and Harries - 2007 paper that Philippe Chantreau pasted a link to was great - thank you. i'm not all the way through it yet (and probably won't until several days the way this week is going....) but i did skim it and read the conclusions. here are a few quick takeaways that will probably get clarified or amplified once i've finished the paper. Fig. 4 showed the delta in OLR from 2003-1970 and again, i don't see how you can look at that graph and claim anything other than no change with regard to wavelengths in the CO2 absorption range. and with regard to the using the model to tease out the water vapor and sst changes - in the appendix the temperatures for 2003 were mostly equal to or lower than 1970 so that should've skewed the actual OLR measurements lower in 2003 (which it didn't). and in the conclusions the authors state that there is "perhaps a deficiency in the modeling due to aerosol or continuum effects." and in all three of the papers i cited in the article (and this new one listed above) the actual measured data show flat or increasing amounts of OLR which is in direct opposition to what AGW predicted in the Ramanathan paper. The simulated, modeled graphs (removing water vapor contributions and sst differences) show a reduction in OLR associated with CO2 absorption but again my whole take on this was to place more value in the real, actual measurements instead of the adjusted data. I understand what the authors (and many of you in your explanations provided here) are doing and why you are doing it and why the authors came to their conclusions (which are in direct opposition to the conclusion i came to in my article). we have a difference of opinion as to which data set has more value. that doesn't mean i'm calling the authors (or anyone here) frauds or degrading them or trying to discredit them. again, let me be clear, i have the utmost respect for the scientists who write these papers (as well as those on here whom i've conversed with) and i believe they are the tops in their field and would never do anything devious or underhanded to misrepresent data to help their argument. I think i've clarified that enough now. Philippe Chantreau - thanks also for your comments on my back of the envelope calculations - i didn't get to devote the time to digest all of your comments the way they deserve but i will. and i recognize the exercise is difficult but has anyone used the BT delta numbers (even the ones that were generated from the models removing SST and water vapor impacts) in these papers, converted that to what predicted temperature rise would be predicted for Earth (form say 1970 to 2006) and then compared that to GISS, HADCRUT3, etc. measurements? I would think this would be a valuable exercise. and contrary to a post (Riccardo #64) about me not even getting the order of magnitude right (which i did, 0.23 C and 0.73C are the same order of magnitude) my admittedly simple model led me to the conclusion that even a -1K BT delta isn't enough to validate the AGW model. i had to resort to that simple model because i couldn't find the calculation done but then again i don't have the extensive body of knowledge and connections that people here have - hence the reason for hanging out with you and the Real Climate blogs.
123627. Charlie A at 06:00 AM on 25 February 2010
        Misinterpreting a retraction of rising sea level predictions
        An interesting peer reviewed article published in Geophysical Research Letters is :"Recent global sea level acceleration started over 200 years ago?", Jevrejeva, Moore, Grinsted, and Woodworth. GRL 2008. http://www.pol.ac.uk/psmsl/author_archive/jevrejeva_etal_1700/2008GL033611.pdf Only 4 pages long and a reasonably easy read, but you can also just skip down to Figure 3, which extracts from the sea level instrumental record a basic oscillatory trend of 60 year period which is superimposed on an accelerating trend starting in the late 1700's.
123628. barry1487 at 06:00 AM on 25 February 2010
        Misinterpreting a retraction of rising sea level predictions
        From the abstract: "First, we tested the sensitivity of our results to the length of the time step used in the integration of the model for the period of deglaciation, which we found to be robust. However, we overlooked that the simulations of the twentieth and twenty-first centuries are sensitive to this time step, which led to an overestimation of the sea-level response to warming in the simulations for these centuries." Aren't they being a bit more specific than saying that their methods are wrong and their conclusions are simply invalid? Are they not saying that their methodology led them to overestimate sea level rise?
123629. Philippe Chantreau at 05:59 AM on 25 February 2010
        Misinterpreting a retraction of rising sea level predictions
        Nice work John. And once again more references than I can look at.
123630. tobyjoyce at 04:08 AM on 25 February 2010
        Have American Thinker disproven global warming?
        @garythomspon (#49), Nice try, and I do like your calm way you have elected to debate this, but I think your amended post on AT has a logical fallacy. You argue concerning the chart #3 that shows the 1907 & 1997 difference that "Since half the wavenumbers experienced a decrease and the other half experienced an increase, the data is not compelling enough to make conclusions either way with regard to OLR for these wavenumbers associated with CO2 absorption." What you are saying is that the curve of OLR differences averages out as 0 (approx.), so we must accept a Null Hypothesis that the difference between 1997 and 1970 is 0. First of all, the model curve also averages out as zero so should we not therefore accept the model as a valid prediction? But you are arguing that the model is wrong - hence the fallacy. Hardly a disproof of a key component of the theory of Global Warming. Further, IMHO, where you are going astray is that you are assuming a homogenous process underlying the curve. However, you can see the CO2, O3 & CH4 absorption bands highliged in grey. The question is - are the separate averages in the absorption bands for the three greenhouse gases significantly different from 0? Not sure about 02 and CH4, but the CO2 band seems to be, though I admit there is not a statistical test in the paper to demonstrate that conclusively. Certainly the model seems to be a good fit in the CO2 band. I think the authors are justified in claiming the following: "Changing spectral signatures in CH4, CO2, and H2O are observed, with the difference signal in the CO2 matching well between observations and modelled spectra.The methane signal is deeper for the observed difference spectrum than the modelled difference spectrum, but this is likely due to incorrect methane concentrations or temperature profiles from 1970. In the future, we plan to extend the analysis to more spatial and temporal regions, other models, and to cloudy cases. " This is good science - the authors publish their results through peer-review, are clearly concerned to establish the accuracy of their model, and clearly intend to do further work to verify their findings. Not the sort of people who deserve to be characterized as rogues and frauds, as your commenters on AT seem to believe.
123631. Jeff Freymueller at 04:07 AM on 25 February 2010
        Misinterpreting a retraction of rising sea level predictions
        The reaction to this one really has been in the up is down category. Many or most scientists who work in glaciology, and many who study sea level, consider the IPCC's projections to be only a lower bound on future sea level rise. That is, actual sea level rise is almost certain to exceed the IPCC projections. Why? Because the IPCC assumed that glacier flow would not speed up as temperatures warm. Their reason for excluding a contribution from enhanced glacier flow in the future is that the uncertainties in future projections of it were large based on the literature as of the IPCC cutoff date. In the Third report a few years ago, they had tried to include this contribution, but this time they did not. There are two problems with the IPCC's decision. First, a slowdown in glacier flow with warming temperature is very, very unikely. What we have seen so far is that glacier flow is speeding up with increasing temperature. It is just hard to predict how much more speedup there will be in the future. Second, the major contribution to sea level from Greenland and Antarctica does not come from meltwater running off, but from glaciers flowing faster and dumping ice into the ocean, where it melts. So the bottom line is that the IPCC projection excluded a component that is highly uncertain, but almost certainly positive. Sea level rise will almost certainly be faster than the IPCC projection, but there is disagreement on how much faster. That's the context of the Siddall paper. They got a relatively low projected future rate, which would have been a fairly big deal given that a lot of other work in the last few years has pointed to much higher rates. John is absolutely right -- the authors retracted their paper's conclusions of low future sea level rise, because when they fixed their error, they get a much higher future prediction. They explained the error in the retraction letter. Their basic method was sound. But the time step they used in the integration of their model was too long to be used for 20th century sea level rise and 21st century predictions. Effectively, by using a time step that was appropriate only for reconstruction over a much longer time scale, they smoothed out the recent and projected rise, getting a lowball estimate.
123632. SLRTX at 03:06 AM on 25 February 2010
        Misinterpreting a retraction of rising sea level predictions
        "Skeptics" (we'll call them that for now) confuse the facts supporting anthropogenic climate change (ACC), and the effects of those changes. Estimations of changes to sea levels falls into the category of effects of ACC. Whether or not the models to project the effects of ACC were off a bit still does not change the facts supporting ACC.
123633. chparadise at 03:04 AM on 25 February 2010
        Misinterpreting a retraction of rising sea level predictions
        In a way, this paper --> investigation by another group --> questions raised --> voluntary retraction is exactly the sort of way in which science is supposed to work. However, it's going to be tough convincing some of the non-scientists of this, since they don't know just how well scientists police themselves.
123634. Dan Olner at 02:31 AM on 25 February 2010
        A brief history of our iPhone app
        Got the app, brilliant. Looking forward to seeing the results of which arguments people are meeting. There's more scope for simple apps (both phone and interwebs) for this sort of education. One clearly in dire need is something simple to illustrate 'statistical significance.' My thought on that was: a pair of dice, which may or may not be loaded. When a run of sixes comes up, how likely is that to be chance, how likely a problem with the dice (or die... er... never sure which way round that is!) That would nicely illustrate that the level of statistical significance is partly a choice. (Given an infinite universe, after all, it could end up like Rosencrantz and Guildenstern and their never-ending coin-flips coming up heads...) Not sure what simple examples for time series could be concocted. Perhaps take a slot of time and ask "are we heading to winter or summer?" (say you've just come out of a coma, in the middle of nowhere, with a stats book and a weather station. How many days before you can be sure?) The misrepresentation (or deliberate twisting) of Prof Jones' statements about significance really alarmed me. Can journos really not know such basic stats? (Or do they just not care?)
123635. SaganGathering at 00:40 AM on 25 February 2010
        Other planets are warming
        I'd just like to point out that it's absurd to claim with any confidence that any other planets or moons are warming, when we have so little data about them- all the while ignoring our vast armada of land and sea based temperature probes right here on Earth (and orbiting satellites). We know far more about the temperature trends on our own planet than on any other planet, and yet certain people use highly questionable speculations about other planet's temperatures to try to dismiss the trends we see here at home. We have laughably few samples of temps on other planets as compared to the astounding array of data on our own Earthly climate trends. For example, we have a handful of probes on Mars and an orbiter. Mars is the planet we probably know the most about besides Earth. With that equipment we can only get the faintest idea of what's going on with the temps there. To use this data (or records from other planets) as reliable evidence of anything more solid than the temperature sampling we have for Earth, is on its face absurd. I would also like to say that there's too much attention paid to CO2 alone. Methane and Nitrous Oxides maybe be at least as problematic. Most of this comes from livestock production. Certainly, getting them under control first will give us more return on investment.
123636. Jesse Fell at 23:07 PM on 24 February 2010
        Have American Thinker disproven global warming?
        My understanding of the Earth's heat balance is that it will, in the long run, be a balance between heat energy reaching Earth from the Sun and the amount of OLR that the Earth emitting back into outer space. Granting for the sake of argument that there has been no reduction in the amount of OLR in recent decades, wouldn't that mean simply that the Earth had found a way to achieve balance in spite of the undeniable increases in atmospheric CO2? And the Earth has only one way to achieve balance given the CO2 buildup: by getting warmer. If this understanding is wrong, please help me out.
123637. Berényi Péter at 22:47 PM on 24 February 2010
        What would happen if the sun fell to Maunder Minimum levels?
        #59 Marcus at 12:13 PM on 22 February, 2010: "So I'd love to know how Beranyi has gotten his figures" I've given a brief description. Read it. Do it. Try to replicate. I can answer any specific question, but not interested in what you'd love to do. Or you can calculate July trends from GHCN by whatever method you see fit. Describe the method, show results. However, I can tell you the specific reason I have found a centennial decreasing trend in GHCN July temperature data. Unfortunately GHCN is dominated by USHCN stations. There is no legitimate reason it should be this way. Except it was created in America, by Americans, for Amaricans perhaps. Rather silly explanation. Weather stations in Europe have long and stable histories, still, they are absolutely underrepresented in GHCN. Worse, European record is full of discontinuities. Now. There were severe US July heat waves in several consecutive years during 1930s (see any history book on Dust Bowl in Dirty Thirties). It was not unique to Northern America thogh. In Hungary Julies in early 1930s were 0.6°C warmer than present on average. The pattern can be observed all over Eastern Central Europe as well. Looks like data collection policy of GHCN is more than sloppy. Global Historical Climatology Network (GHCN) (DSI-9100) Metadata from the NOAA Metadata Manager and Repository (NMMR) http://www.ngdc.noaa.gov/nmmrview/xmls/fgdc.jsp?id=gov.noaa.ncdc:C00422&view=html An Overview of the Global Historical Climatology Network Temperature Database 1997, Thomas C. Peterson* and Russell S. Vose http://www.ncdc.noaa.gov/oa/climate/research/Peterson-Vose-1997.pdf There are much, MUCH more data out there. First thing to do is to COLLECT it (with as much metadata as possible). Then PUBLISH it on the web, making it freely available to all. UK Met Office Proposal http://wattsupwiththat.files.wordpress.com/2010/02/metoffice_proposal_022410.pdf Even this porposal is too rigid. Data collection & verification is not rocket science, one does NOT need peer rewieved literature to accomplish it. Just open standards (like RFCs for the net) and several open source community projects to do evaluation. Way cheaper, more transparent, built-in quality assurance procedure developed for open source projects in general. "Publish early, publish often" How open collaboration works: an introduction for scholars by Larry Sanger http://www.citizendium.org/how_openness_works.html
123638. AndrewY at 22:10 PM on 24 February 2010
        A brief history of our iPhone app
        Having a mobile app containing the information on this site is such an excellent idea. It might be worth considered developing an app for the Symbian mobile OS? The Symbian OS actually has the majority share of the smart phone market (in Q2 2009, more users than all the other platforms put together http://en.wikipedia.org/wiki/Smartphone). It is not widely used in the US but it dominates the smartphone market in the rest of the world. It also recently became fully open source, with the platform releases and developer support being managed by the not-for-profit Symbian Foundation (http://www.symbian.org/). I'm not sure if developing apps is as easy as for the iPhone, but it may be worth a look? BTW I am glad I found this site, you are really making a great contribution here, helping people to find the facts and understand the arguments more clearly. Cheers for that!
123639. Riccardo at 19:18 PM on 24 February 2010
        Have American Thinker disproven global warming?
        garythompson, i hope that you (or anyone else) is not going to use these rather crude calculations to prove or disprove anything. In the response to John, Harries pointed out that one should be carfull in using brighteness instead of radiance: "to sum up all the energy you would have to use the radiance spectrum, not the brightness temperature spectrum. Though they are equivalent, the transform from one to the other is not linear. So, integrating brightness temperature would not be easy to interpret.". The average brightness, for example, is not the same as the average radiance. The correct calculation should be done with the full spectra as radiance, taking the non saturated part (which cannot be done with Harries spectra), calculating the difference and integrate. And even this is not accurate enough as, again, pointed out by Harries. It's rather odd that you think it is possible to disprove science made by professional scientists with a few hand calculations on numbers obtained drawing lines on a graph. At best you can get the order of magnitude, in this case not even that.
123640. Dikran Marsupial at 19:08 PM on 24 February 2010
        What would happen if the sun fell to Maunder Minimum levels?
        Cowboy @ 81 The argument that the rise in CO2 is anthropogenic doesn't rely solely on correlations, a simple piece of accountancy is enough to verify that it is true. The annual increase in atmospheric carbon is about half the annual emissions (fossil fuel + land use), and the remaining carbon has to go somewhere. This excess carbon must be being taken up by the natural environment (oceans + terrestrial biosphere) somewhere, which proves that the natural environment is a net sink (over a full annual cycle). The bottom line is that if the natural environment were a net source of CO2 then the annual rise in atmospheric CO2 would be greater than annual anthropogenic emissions, but this is observed not to be the case, and hasn't been the case for over 150 years). As I said there are some things known with considerable certainty (Ferdinand Englebeen has an excellent website discussing this and other lines of evidence).
123641. Cowboy at 18:22 PM on 24 February 2010
        What would happen if the sun fell to Maunder Minimum levels?
        "Cowboy, correlation is necessary to demonstrate causation--just not sufficient." Understood. It indicates the possibility of some kind of relationship, but does not establish cause/effect or the "degrees of separation". But if one set of data consistently leads or lags the other, it can help direct looking for any actual causality. Thx for all the feedback. I believe that going through a "primer" on the science will actually be more meaningful after getting some of the preconceived ideas (correct or incorrect) in better perspective as much as possible/practical first. I'm just pretty certain that I would to some extent be distracted by those things, and be looking more for support for what I might think I wanted to find/prove rather than at the science for what it is. Granted, starting with a premise to prove or "disprove" may be scientific approach, but I know for example that too often data 'normalization' and 'filtering' can be influenced by a desire to prove a premise.
123642. Leo G at 17:12 PM on 24 February 2010
        A brief history of our iPhone app
        A bit O/T - just wanted to let you all know, that it is snowing on Cypress Mtn. @ the Olympics, but raining at my house :(
123643. Philippe Chantreau at 16:45 PM on 24 February 2010
        Have American Thinker disproven global warming?
        G Thompson: OK, I more or less follow you reasoning. I believe that it is overly simplistic, by far. At the top of the troposphere and above, CO2 produces cooling due to complex mechanisms that are related to the decreased IR reaching these levels as a result of the increased tropospheric CO2 at lower altitudes. Iacono and Clough did the work on this and Chen relies on Clough's updated radiative transfer model from 2005. All of this needs to be taken into consideration in order to determine if the upper troposheric OLR really correponds to expectations. The conclusion reached in the paper you used is that it does. Your calculations constitute a model, whether you realize it or not. I am not ready to give it more credence than LBLRTM or MODTRAN, both of which show radiative forcings at the surface far different from your back of the envelope model. I also believe that your model diverge from surface obervations of downwelling IR. I have no reference at this time but will provide some if I have the time (I have a life too). In any case, I doubt that the upper troposheric or TOA OLR can be used as a measure of the radiative forcing at the surface the way you did. This is no amateur work and it would be nice to have someone truly knowledgeable of atmospheric physics to help out (most of it is beyond me). I know that this is the stuff normally done with line by line radiative transfer models. The fact that the obervational data very closely matches the modeled results indicates that they've got it right. I will readily concede that some fine tuning may be needed on methane. The Griggs & Harries 2007 paper uses MODTRAN, and more observational data than the 2001 paper had, and the 2001 results are overall confirmed. The point is this: both of the papers you cited compare model results to observational data, in order to confirm that the models showing enhanced GH effect got the radiative transfer right at these higher altitudes. Both papers confirm that they did. Some details diverge, as anyone would expect. Obsevations exactly identical to model results would be suspicious. Your ending comment in the AT piece is thereby entirely unwarranted. BTW the Griggs and Harries 2007 paper can be found here: http://ams.allenpress.com/perlserv/?request=get-document&doi=10.1175%2FJCLI4204.1 And for Pete's sake, people, let's cut on the pedantic grammar remarks. They add nothing to the discussion. Are we going to look at typos next? Please...
123644. 70rn at 16:33 PM on 24 February 2010
        Have American Thinker disproven global warming?
        Though I acknowledge their necessity, the first page of this thread looked rather impenetrable at first glance.
123645. 70rn at 16:30 PM on 24 February 2010
        Have American Thinker disproven global warming?
        A three letter Acronym.
123646. garythompson at 16:25 PM on 24 February 2010
        Have American Thinker disproven global warming?
        typo in the spreadsheet carried over so a correction to the last few sentences of my previous post. From the RC link, 1.6W/m2 is not correct, the aerosols and natural changes is 0.9 W/m2 so that takes 3.74 W/m2 to 2.84 W/m2 and that equates to a temp increase of 0.23C. Sorry for the error, it's late here on the east coast of the USA.
123647. Jeff Freymueller at 15:36 PM on 24 February 2010
        A brief history of our iPhone app
        #4 Albatross, you read it backward. The claim was that all iPhone owners are lefties, not that all lefties own iPhones. The latter must be a failure of the Socialist International, which somehow failed to requisition enough iPhones for all lefties. The app seems like a great thing. No iPhone for me, though, so I'll just have to make do with the website. I also would love to see a one-stop anti-Skeptical Science app, especially if it could explain how mutually contradictory arguments constitute absolute proof that climate science is wrong, no doubt about it or room for skepticism!
123648. 70rn at 15:34 PM on 24 February 2010
        Have American Thinker disproven global warming?
        The number of TLAs in this thread is starting make it look like a military briefing.
123649. garythompson at 15:22 PM on 24 February 2010
        Have American Thinker disproven global warming?
        Regarding post #51 - Philippe Chantreau - You say: " I still think this data isn't compelling enough to draw a conclusion about the OLR decreasing over the spectrum of CO2 absorption and I didn't change any of my conclusions because I still believe those." On what calculations/scientific assessment do you base these beliefs? " Fair question. let me see if i can do a good job of explaining. WARNING - I'm about to try and hyperlink references. not my strongest skill. if there is an issue, i'll follow up with another post with the links. and i apologize for the long post, it's hard to explain without graphics..... remember that I am arguing that there is no OLR delta between 2006 and 1970 over the regions where CO2 absorb and i feel the proof of that is fairly evident from the graph showing the delta but let's say I'm using "biased" eyes and in reality there is (on average) a -1K delta in Brightness Temperature (which could be argued from figure 5 in my article if you focused more on the lower wave nubmers/cm and ignored the higher wavenumber/cm portion that actually shows an increase in OLR). But let's assume that -1K delta and see what that equates to in W/m2 delta over 36 years. Once we get that difference of OLR flux let's plug that in the Radiative forxing X Climate sensitivity and see what temperature it predicts we should've seen. I'm going to do that by assuming calculating the W/m2 for an two ideal Blackbodies (that are radiating 1K different temperature) over all wavelengths to get the delta for the entire spectrum. Then, taking the ratio of that area under the blackbody curve which we are concerned with - the 700-780 wavenumber/cm and the other peak (which isn't shown on the data but we know is there - although it's OLR is less as we know from < a href="http://cimss.ssec.wisc.edu/goes/sndprf/spectra.gif" > here ) find out what proportion of the overall delta is associated with CO2 absorption. but first let's look at that ratio we are concerned with. As I noted in my post (#28) and as RC noted < a href="http://www.realclimate.org/index.php/archives/2007/08/the-co2-problem-in-6-easy-steps/" > here under Step 2, calculating the OLR flux from this data can't be calculated by hand. But let me try and simplify the situation and make it a worst case situation and see if that makes the calculations easier. As is noted on the RC post < a href="http://www.realclimate.org/index.php/archives/2007/06/a-saturated-gassy-argument-part-ii/" > here and the post on this page topic (#34 Riccardo) the CO2 absorption is saturated at and around the peak (15um) and all we are left with are these "spurious peaks". So these edges are all we'll be concerned with since the saturated delta will be zero. Next, pull up the graphs 3 and 4 in my article which correspond to the TES and IRIS measured data (2006 and 1970 respectively). you can see that they both roughly start around the 220K BT (for 700 waves/cm) and then rise to about 290K BT at around 780 waves/cm (which comprises the CO2 absorption range for the data in this paper). for the sake of estimating (and doing this by hand) let's treat that entire region as if it were a BT of 255K (in the middle of that linear rise). I realize this is an assumption but as I stated above, the other side of this absorption will be less so I feel I'm being conservative and biased toward the AGW position. Take a curve showing the radiation of a black body that is at 255K. plot that out and draw verical lines at 13.5um (750 waves/cm) and 17um (588 waves/cm), then shade that region of the curve in. that represents the wavelengths that are absorbed by CO2. If you ratio that integrated area to the total integrated area of that curve (over the entire wavelength range) you get around 21.5%. I'll be generous and even call it 22%. Notice also that the wavenumbers/cm shown in the three cited papers (starting at 700) represent the higher magnitude radiation on this 255K radiation curve (whose peak amplitutde is around 11um). If we assume at and around the 15um area that there is total absorption then let's say that portion that absorbs to extinction is half of the total inside that shaded region (and on the page of RC that talks about CO2 saturation that sounds conservative). So, half of this energy in the shaded region is what we'll use to calculate the W/m2 conversion from the data in the cited paper. so that 22% is now 11%. Let's use Stephan-Boltzman Law to find out what the delta OLR flux would be for two ideal black bodies who were separated by 1K (255 vs. 254K). taking 255^4 minus 254^4 and then multiplying that result by 5.67x10^-8 you get 3.74 W/m2. so the delta in energy from those ideal Blackbodies for all wavelengths was 3.74W/m2. but we are only interested in the part that CO2 absorbs and taking 11% of that yields 0.41 W/m2. so in 36 years we see a difference in OLR of 0.41 W/m2. Assuming 100% of that contributes to forcing attributed to GHG and using the climate sensitivity factor of 0.75C/(W/m2) which is also in the first RC link, you get a contribution of 0.31C in 36 years! so at best, using VERY conservative estimates (which i don't agree with) the OLR reductions contributed at worst 0.31C warming to the earth from 1970 to 2006. According to GISS trend map from 1970 to 2006 we've seen a warming of 0.73C. Even with my oversimplifications and estimates to skew the number higher, we see the predicted increase is less than half of the observed. and this is neglecting the net cooling forcing due to aerosols and natural changes which is 1.6 W/m2 (again, mentioned in the first RC post). If we deduct 1.6 W/m2 from the 3.74 W/m2 then we get 2.14 W/m2 and that takes the temperature delta down to 0.18C (after multiplying by 11% and 0.75C/W/m2). i'm interested in feedback on my method and math - PLEASE!
123650. Jeff Freymueller at 15:18 PM on 24 February 2010
        Have American Thinker disproven global warming?
        I'd like to think that American thinkers are plural, even if I have my doubts about the magazine! Two nations separated by a common language, indeed. I commend Gary Thompson for coming here to discuss the issue politely, but Phillipe Chantreau's comments (#51) really are damning, and yet at the same time probably too kind. I don't see any defense for either sentence in that paragraph, nor is the rest of Thompson's analysis compelling. "My interpretation of data from three papers, which is not quantitative and is opposite to the interpretation of the authors, and in some cases not supported by actually doing the subtraction ..." would be a more accurate statement, I think.

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