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Comments 124601 to 124650:

124601. Pierre-Normand at 21:49 PM on 25 February 2010
        Have American Thinker disproven global warming?
        In my post #72 I misstated Ramanathan's definition of OLR. The 'reduction' in OLR Ramanathan speaks of is conceived as the difference between longwave flux from the surface and total longwave flux from top of atmosphere (wherever this is being emitted from). With increased CO2 concentration, when steady state is achieved, the 'reduction' is larger than is was just because surface emission is larger. OLR does not change one bit, since it must still balance the same solar flux.
124602. Arkadiusz Semczyszak at 21:49 PM on 25 February 2010
        Misinterpreting a retraction of rising sea level predictions
        The mass of ice, the extent of glaciation from the last interglacial period (125.000 years ago), were higher than during the last glaciation.
124603. Arkadiusz Semczyszak at 21:38 PM on 25 February 2010
        Misinterpreting a retraction of rising sea level predictions
        "It stood 4-6 meters above the present during the last interglacial period, 125,000 years ago, but was 120 m LOWER [...] at the peak of the last ice age, around 20,000 years ago." - "Sea Level Rise, After the Ice Melted and Today" (http://www.giss.nasa.gov/research/briefs/gornitz_09/). Post-glacial isostatic rebound, and it also should be included ... Much better to compare (here) is an early Holocene optimum.
124604. AndrewY at 21:14 PM on 25 February 2010
        Misinterpreting a retraction of rising sea level predictions
        RSVP @39/42, I am a reader and do not represent the views of the people that maintain this site, but I don't think it is very meaningful/constructive to divide the people that post here into opposing camps labeled "skeptics" and "others" (your question seems to be "what are the "others" called?)... I think doubt lies at the heart of the scientific method, so in that sense everybody here is a skeptic. It seems to me that the purpose of this site is to shed light on/expose those arguments that either misinterpret, misunderstand or misrepresent the current body of scientific research (ideally the focus should be on the arguments, not the people). Returning to the topic, it does seem the Siddall abstract is very easy to misinterpret (unless you are careful to find the definition of sea level response), I am surprised the authors did not see the potential for that misunderstanding (especially as they were withdrawing a paper). Unfortunately, climate scientists are working in a very politically charged field and need to take extra care to be completely clear about their findings, especially in the abstract and conclusion. It is no longer just an academic audience that is reading their papers and in the age of the internet a misunderstanding can spread like wild fire and can be very difficult to reverse (there are lots of examples of that!)
124605. RSVP at 19:48 PM on 25 February 2010
        Misinterpreting a retraction of rising sea level predictions
        #40 The answer to my question requires just one word. I dont see your reply as answering my question (at all). It is characteristic in circles or prejudice to consider those within the group as "normal", and only have labels for those outside the group.
124606. RSVP at 19:42 PM on 25 February 2010
        Misinterpreting a retraction of rising sea level predictions
        Also, as a practical matter, one normally applies the branch of science that best fits the problem to be solved. When dealing with a global problem such as global warming, it would seem that simple thermodynamics could give you most of the answers one needs when it comes to analyzing energy balance. After that, the problem is either regarded acute/drastic, or subtle/minor. According to all the predictions, supposedly the situation is fairly acute/drastic. Acute/drastic problems, require acute/drastic solutions, and yet it seems that the very folks that take their work so seriously here are the same that are only able to prescribe whimpy solutions such as curbing CO2 emissions and looking for "alternative" energy sources that in end also have their own thermal footprints. If the problem is indeed linked to humans activity, it is not because of what a few people are doing. It is a problem of big numbers. And if there being so many people is creating a problem, the issue is about dimensionality. This then calls on other scientific disciplines that naturally fit the problem, such as behaviorial psychology, sociology, economics, and political science.
124607. Pierre-Normand at 19:23 PM on 25 February 2010
        Misinterpreting a retraction of rising sea level predictions
        Skepticism denotes one main component of epistemic virtue. Everyone is for virtue. So, everyone claims to be advocating true skepticism. I can hardly find a more polite way to refer to people who expresses a level of doubt that seems to me unwarranted than to call them skeptics -- in relation with some position that seems well established, such as AGW -- when they usually claim the title for themselves. I'd rather not call someone a denier when I wish to engage in dialogue with him/her.
124608. Dikran Marsupial at 19:16 PM on 25 February 2010
        What would happen if the sun fell to Maunder Minimum levels?
        Cowboy @ 86 Fossil fuel use is highly taxed, and thus quite well accounted for. As a result our estimates of fossil fuel use are sufficiently accurate for there to be little question of the validity of the mass balance argument. This is helped by the fact that the annual increase in atmospheric concentrations is less than half annual fossil fuel use emissions, so estimates would have to be wrong by a factor of two before there would be any doubt. The error bars simply are no where near that big. So to return to our example, if you knew that you put in $1000 per month, with a random month-to-month variation of $100, and took out nothing, but your monthly balance only rose by an average of $500 a month (plus or minus $100), you would still know that Mrs Cowboy was a net drain on your finances and you were a net source. You would know that (assuming basic numeracy) without needing actual exact transaction receipts (tags) or a ledger over a statistically significant time (note we have excellent records of emissions and the growth rate for at least 50 years), and that would be true if she were putting in $1 or $1,000,000 or $1,000,000,000 a month. Now if you can provide some evidence that our fossil fuel use has been over-estimated by a factor of two, rather than the error bars supplied with the data, then lets hear it.
124609. RSVP at 19:04 PM on 25 February 2010
        Misinterpreting a retraction of rising sea level predictions
        "Skeptic" is the operative label at this website for those that doubt or even question IPCC conclusions. For all my reading here, I am still not sure what the correct term is for non skeptics. Would anyone know the answer to this question?
124610. SaganGathering at 18:59 PM on 25 February 2010
        Mars is warming
        I'm not going to address the data directly just now, because there's another problem with the "other planets are warming" argument. Here it is. We have a handful of probes on Mars and an orbiter. Mars is the planet we probably know the most about besides Earth. And even with that equipment we can only get the faintest idea of what's going on with the temps there on Mars. Or other planets for that matter. We have laughably few samples of temps on other planets as compared to the astounding array of data on our own Earthly climate trends. It's absurd to claim with any confidence that we know for certain that other planets or moons are warming or cooling, when we have relatively little data about them -- all the while ignoring our vast armada of land and sea-based temperature probes right here on Earth (not to mention orbiting satellites). Should we dismiss the data we have on our own planet's temperature trends because of a smattering of temperature measurements on any other planet? Which data-set do you think would be more reliable? The one we have here at home, of course. Because we have many, many more sources and samples, and over a longer period of time. 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 planets' temperatures to try to dismiss the dta trends we see here at home. 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 Earthly CO2 alone. Methane and Nitrous Oxides may 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, and quicker too.
124611. mothincarnate at 16:26 PM on 25 February 2010
        A brief history of our iPhone app
        I have a Nokia N97 - will a similar app be available for that in the future?
124612. Pierre-Normand at 16:05 PM on 25 February 2010
        Have American Thinker disproven global warming?
        The SST temperature is an increase in surface temperature but the longwave energy (roughly 90%, if I recall) is being emitted from high in the stratosphere mostly in wavelengths that the atmosphere is opaque to. This emitting layer has cooled, not warmed. This is where the "swamping" occurs, because of the cooling that itself is the result of increased CO2 (and water vapor) concentration that shielded it from the warmer layers below. It needs not occur in the GHG bands only, as you seem to assume. And the total effect must be small if the system is close to being in radiative balance. Solar input did not vary (much), so neither does total emissions from both the top of the atmosphere and all the layers below.
124613. Matt Andrews at 15:18 PM on 25 February 2010
        A brief history of our iPhone app
        Great job - this iPhone app is an excellent example of how to translate a desktop website effectively for the small screen. John, I suggest you suggest to the developers that they look into PhoneGap - it's an open source development framework which takes a web application (html/css/js, including JS interfaces to native mobile features) and compiles native apps for iPhone, Android, Blackberry, Windows Mobile, Symbian/Nokia, etc.
124614. garythompson at 15:05 PM on 25 February 2010
        Have American Thinker disproven global warming?
        Doug_Bostrom #70 - "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?" i think that is an outstanding suggestion. Allow me a day or so to go through that and hit the bullet points and post something. i am no different that the rest of you on here in that i have a family and job that takes a higher priority so we all understand that this 'conversation' is a bit like one between an earthling and someone on Neptune. And i'm way out here, all alone on Neptune and i have 20 people on Earth sending me questions! but i'm not complaining, this is fun and i'm flattered that all here have willingly expended some of their valuable time in a conversation about this topic. i echo Ned's comments (#75) very frequently about the more you learn, the more you realize you didn't know. and that is what makes it fun. i also need time to, like Jesse Fell (#68) stated, to huff and puff through some of the exellent replies today. i would like to make this request though. in regard to John's article here and other postings here related to my A) apparent misrepresentation of the author's conclusions and B) leaving out graphs/data that is in opposition to my position. i feel i have clarified my position on those justified arguments in these posts, in my article revision and on the subsequent post on that article (in AT). i took full responsibility for that misconception due to my words in the article, apologized and i will not bother addressing those points either in John's article or posts here. remember that my article was written for American Thinker which is a blog which i also go to daily to get fresh takes on current topics and the editor's there thought my article was a fresh take that had not been put forth to a wide audience and they gave me that audience. for that i'm grateful and as an unpredicted consequence a fruitful conversation has sprung up here. it was an article expressing my opinion and i tried to support that opinion in the article and i am continuing to elaborate more on that in this forum which is better suited for the detailed science. it was an article, not a peer reviewed paper (although i seem to be getting plenty of that review now!). but i still want to get my position and facts right even though it is not a peer reviewed science paper. my name is on it and i wouldn't have written about that position if i didn't believe i was right. for the record, the peer review process is robust and i feel that is the right way to do things in science as long as the review is open, honest and unbiased toward the science. one more comment on the other half of your post Doug relating to the part of my article regarding Lindzen and Choi. of course you are correct that they evaluated the entire OLR spectrum and didn't have granularity into the spectrum that CO2 absorbs. let me explain why i made that statement in my paper. In Lindzen and Choi, the made the statement in the concluding remarks (section 3[14]) that ERBE differed significantly with models and showed that OLR increased with SST but the models showed it decreasing. And again, in the Ramanathan paper, he made the general statement that OLR would decrease with increased CO2 in the atmosphere. i could be reading too much into the Ramanathan paper but i feel that even the statement of Lindzen and Choi make my statement not incorrect. although, like you, i'd prefer to draw conclusions on CO2 by just looking at the spectrum that it absorbs. and one more point that is sort of on that topic and this was the main theme of why i wrote the article. from 1970 to 2006 the global temperatures rose by 0.73C and looking at the percent increase of IR using Stephan-Boltzmann i get a 1.02% increase (comparing 288K with 288.73K). by my estimates CO2 concentration went up 18% (from the mauna loa data). So shouldn't this much larger increase in CO2 have swamped out the increase in increase in overall OLR from the SST (which is the point i think Ramanathan was making in his paper)? I would've expected clear drops in OLR in the CO2 absorption spectrum even on the actual measured data even without compensating for SST. at best we are squinting and arguing over deltas that have values of 0 to -1K BT in the CO2 absorption spectrum. -1K of BT change equates to what with regard to predicted temperature increase? i don't know, my grossly simplistic calculation above is all i have to go on so that is why i'm here to ask the experts. ok, i'm sorry that is all i can respond to tonight but i'll plan to provide what you asked for later tomorrow night.
124615. dhogaza at 13:43 PM on 25 February 2010
        Misinterpreting a retraction of rising sea level predictions
        

        To be fair to Berényi Péter, the word 'overestimation' also led me to ask upthread if that meant sea-level rise had been overestimated.

        It had me wondering, too. You and I investigated. Berényi Péter said it means there'd be less sea level rise than predicted. That's a qualitative difference some folks might learn from ...
124616. barry1487 at 13:36 PM on 25 February 2010
        Misinterpreting a retraction of rising sea level predictions
        To be fair to Berényi Péter, the word 'overestimation' also led me to ask upthread if that meant sea-level rise had been overestimated. Only having access to the abstract, I didn't know what 'response' referred to, and I did wonder. Thus I asked a question rather than pretended to an authoritative view, which is hardly warranted if you haven't read the whole paper. My query was satisfied by following the trail pointed out by others here. No acceleration upward at Stockholm, Sweden either. I could download the entire PSMSL dataset and compute acceleration for each tide gauge, but I can't believe it is not done already. Sea level change and rate of change is different even within a few hundred kilometers. As far as I'm aware, the tide gauge record from 1870 shows an accelerated increase. http://www.cmar.csiro.au/sealevel/sl_hist_few_hundred.html
124617. HumanityRules at 13:30 PM on 25 February 2010
        Misinterpreting a retraction of rising sea level predictions
        Response to #34 and #35 I'm not even sure that is a climate skeptic blog it looks like a rightwinger mainly concerned with slamming Obama from the list of entry titles. I just think if you are going to lead with a title that suggests skeptics are using this retraction to say sea-levels aren't rising you shouldn't use an obscure rightwing blog to make your point. After all in the final paragraph you seem to tarnish all skeptics with this one mans opinion. This is not the skeptical concensus from the look of things.
124618. dhogaza at 13:05 PM on 25 February 2010
        Misinterpreting a retraction of rising sea level predictions
        Uh, HumanityRules, the lawyer in question got corrected in the comments. That's not quite the same as suggesting that his blog post isn't arguing that sea levels won't rise. His only post in the comments section suggests he didn't quite understand the implication the first time his error was pointed out (he suggests it means that the *lowest* estimate can't be established, and says nothing about the upper). And least he did try to understand the correction. I'll give him points for: 1. Letting posts through showing his interpretation was wrong. 2. Not showing the kind of stubborn attachment to a misinterpretation that a Certain Someone on this blog is showing. 3. Being such an unknown blog that the corrections weren't immediately screamed down by a horde of the typical denialist trash. We'll see whether he'll state something showing he actually understands the full depth of his misunderstanding .
124619. HumanityRules at 12:57 PM on 25 February 2010
        Misinterpreting a retraction of rising sea level predictions
        I'm not sure that the blog you linked to is really arguing that sea levels won't rise. The title and first line maybe a little tongue in cheek but generally they are reporting the facts of the situation. Similarly a more (dis)respected skeptic blog WUWT reported this mentioning the Vermeer and Rahmstorf estimates as you do. Seems like you are setting up a paper house to knock down.
        Response: Some will report it accurately, others lead with headlines like 'Now You Can Forget About Those Rising Seas'. I'm in the unfortunate position of having to respond to the lowest common denominator.
124620. dhogaza at 12:24 PM on 25 February 2010
        Misinterpreting a retraction of rising sea level predictions
        Berényi Péter, your chance of regaining credibility here would probably go up a bit if you acknowledged your interpretation of Siddal's comment about "overestimating the sea level response" was incorrect. I didn't go to all the trouble of making that post just to see you ignore it.
124621. chris1204 at 12:09 PM on 25 February 2010
        Misinterpreting a retraction of rising sea level predictions
        David: 'Hard to see any winners this time around.' As a highly technological society, we are vastly more adaptable then hunter-gatherer societies. Moreover, extinctions are neither good nor bad - were there no extinctions, there would be no evolution. Extinctions (like the poor) will always be with us. So too with change. Not that we want to accelerate extinctions (or increasse poverty) if that can be avoided. The real issue relates to the priorities we set for our resources. If we try to do this as rationally as our limited knowledge permits and avoid emotive value judgments, we are likely to emerge with better outcomes.
124622. kwinters79 at 12:04 PM on 25 February 2010
        Misinterpreting a retraction of rising sea level predictions
        Berényi Péter (22) wrote: "Fitted least squares parabola to data (960121.rlrdata), coefficient of x^2 negative. " That's quite odd, because when I do that I get a positive coefficient for x^2. 0.0023, if I use the interval from 1883 - 2008 (skipping the 1878 - 1893 gap) or 0.0036 over the entire 1856 - 2008 period. But the acceleration becomes even more obvious when you plot a series of 30-year linear trend lines. 1900 - 1929 slope = 1.6723 1940 - 1969 slope = 2.8465 1976 - 2008 slope = 3.983
124623. SLRTX at 11:36 AM on 25 February 2010
        Misinterpreting a retraction of rising sea level predictions
        Based on some back/forth I'm seeing in these posts, I see a fallacy that the so-called "skeptics" use. They mis-apply the "appeal to authority" fallacy - which in itself is a fallacy. First, any reasonable person knows no one person can possibly know the minutiae of every detail about climate change. Like any scientific discipline, it's a collective (peer-reviewed) process. Second, because of the first point, we MUST, at some point, defer to other experts. The so-called "skeptics" then claim this is the "appeal to the authority" fallacy. Not. So. Fast. If that were true, we'd all be guilty of that, each time we visit the family Dr. After all, we don't know all there is to know about medicine, but we do "appeal to the authority" when it comes to medical advice. Here's a link that explains that at times it is reasonable to appeal to the RIGHT authority. http://www.nizkor.org/features/fallacies/appeal-to-authority.html So for me, I am perfectly happy deferring to the collective knowledge of the climate scientist, as much as I am happy to take the advice of my family Dr. :-) As I said in my earlier post - being a bit off on the predictions about the timing of the effects of climate change, does not change the fact that ACC is indeed happening. There are, and will be, consequences.
124624. Berényi Péter at 11:22 AM on 25 February 2010
        Misinterpreting a retraction of rising sea level predictions
        #24 Albatross at 10:58 AM on 25 February, 2010 "there is not a diconnect between science and "logic and truth" as you suggest" Right. This is the way it is supposed to be. Unfortunately ideals are not always met. #25 JMurphy at 10:59 AM on 25 February, 2010 "observed local sea level trends may differ greatly from the average rate of global sea level rise, and vary widely from one location to the next" Of course. But right now we are not talking about speed of rise/sinking but acceleration.
124625. David Horton at 11:21 AM on 25 February 2010
        Misinterpreting a retraction of rising sea level predictions
        "It's also a flooded river valley carved out aeons ago before a massive sea level rise. One river valley lost - one beautiful harbour gained." just a tiny missed point here Chris. The period from the river valley to the flooded harbour was long, and the people being affected by it had a highly mobile small population, no permanent infrastructure, and a hunter-gatherer economy that was just as happy fishing in a harbour as hunting in a valley. None of that applies to 21st century Australia or indeed any other modern country. And by way of warning - the last time Australia's climate switched from cool and wet to hot and dry (essentially the modern climate although a bit drier), dozens of large animal species went extinct, unable to deal with vegetation zones shifting outwards over a period of a few thousand years. If this scenario is repeated over a time span of a hundred years or less there are going to be massive extinctions of flora and fauna, and the agricultural communities of regional areas. The only "winners" at the end of the Pleistocene were a few desert species like red kangaroos. Hard to see any winners this time around. Certainly no human winners.
124626. Berényi Péter at 11:09 AM on 25 February 2010
        Misinterpreting a retraction of rising sea level predictions
        #21 Jeff Freymueller at 10:48 AM on 25 February, 2010: "Whether or not you can detect an acceleration in a single tide gauge record is really beside the point" No acceleration upward at Stockholm, Sweden either. I could download the entire PSMSL dataset and compute acceleration for each tide gauge, but I can't believe it is not done already. Any pointer? However, acceleration of even a single tide gauge (or the lack thereof) is remarkable, provided the record is reliable and there is no vigorous tectonic activity in the region. As satellite measured recent sea level rise is faster than estimated 20th century average, it is often cited as proof of acceleration. However, satellites need calibration, must be faulty if no acceleration is detected at ground level.
124627. Ned at 11:06 AM on 25 February 2010
        Have American Thinker disproven global warming?
        I just want to say that this thread has helped me understand some things that I not only didn't understand before but didn't realize that I didn't understand. Thanks!
124628. chris1204 at 11:04 AM on 25 February 2010
        Misinterpreting a retraction of rising sea level predictions
        John Russell: Was it Ghandi who said, "first you'll be ignored; then you'll be laughed at; then they'll fight you; and finally you'll win"? Gather strength everyone; it's always darkest just before the dawn. I don't know what Ghandi actually said. However, he was a politician with an idealistic vision, not a scientist. I live near Port Jackson (aka Sydney Harbour) - one of the most beautiful harbours in the world. It's also a flooded river valley carved out aeons ago before a massive sea level rise. One river valley lost - one beautiful harbour gained. Climate change brings winners and losers like any process in nature. It's helpful to discern likely outcomes - we can try to modify them or adapt to them. However, we have to learn to accept the uncertainties inherent in scientific discourse about highly complex systems and perhaps our own limitations in the face of processes incorporating variables as yet unknown to us. This requires humility - a quality sadly lacking in many advocates on both sides of the climate change divide.
124629. JMurphy at 10:59 AM on 25 February 2010
        Misinterpreting a retraction of rising sea level predictions
        Berényi Péter, please see : http://www.epa.gov/climatechange/science/recentslc.html "In the United States: Sea level has been rising 0.08-0.12 inches per year (2.0-3.0 mm per year) along most of the U.S. Atlantic and Gulf coasts. The rate of sea level rise varies from about 0.36 inches per year (10 mm per year) along the Louisiana Coast (due to land sinking), to a drop of a few inches per decade in parts of Alaska (because land is rising)." Also : http://tidesandcurrents.noaa.gov/sltrends/faq.shtml "Depending on the rates of vertical land motion relative to changes in sea level, observed local sea level trends may differ greatly from the average rate of global sea level rise, and vary widely from one location to the next."
124630. Albatross at 10:58 AM on 25 February 2010
        Misinterpreting a retraction of rising sea level predictions
        Berényi Péter @14 "I care neither for reviewers nor the scientific community, but I do care for logic & truth." That statement is not consistent with you posting here in a science forum. Also, there is not a diconnect between science and "logic and truth" as you suggest. Whether you like it or not, the research in question has been undertaken and reviewed by scientists who are experts in the field. You should care what they have to say b/c they have invested infinitely more thought and effort on this problem than anyone us here. "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." I'm not appealing to authority, and I am very familiar with how science is done. There is nothing wrong with acceptingand acknowledging that soneone is an expert whether they be a cosmologist, oncologist or climate scientist. I do not know to which "scientific authority" you are referring. As for understanding stuff, dhogaza and others have explained to you why you do not understand as much about this complex problem as you might think. And that is not a slight, we here are all in pretty much the same position in terms of level of understanding and, for reasons stated earlier in this post, we should be very cautious about being cavalier or simply dismissing the science. Science is, whether you like it or not, remarkably good at self correcting. It also advances if someone, like you who is critical of the methods and analysis, is willing to invest the time and effort to improve upon previous work and address the perceived weaknesses, rather than simply poking holes in someone elses work. I, for one, don't care what your credentials are, so long as you can undertake solid research which survives the rigour of peer-review and subsequent critique by the collective expertise in the field, then you have advanced the science. Like it or not, the science is converging towards the higher end of the expected range of increase in SLR. A recent study by SCAR projected that sea level will increase by as much as 1.4 m by 2100-- and SLR will not magically stop rising in 2100. Just as an oncologist is not paid to ignore unfortunate diagnosis and plausible outcomes/prospects for recovery (or not), nor are scientists paid to avoid telling us about the threat of potentially serious scenarios. That is not being "alarmist" is is being prudent and responsible.
124631. Ned at 10:57 AM on 25 February 2010
        Misinterpreting a retraction of rising sea level predictions
        Berényi Péter writes: I am prone to err as anyone, correction is welcome. However, in this topic I have not seen a valid one yet. You must have missed dhogaza's comment here, which did a nice job of correcting your misunderstanding about the meaning of the expression "an overestimation of the sea-level response". What was overestimated was not the rate of rise, but the time scale of the leveling off in rise once available land ice has nearly all melted. That's something that won't happen until nearly all the ice is gone, so the implication of this is clearly that Siddall's paper underestimated 21st century SLR.
124632. Berényi Péter at 10:49 AM on 25 February 2010
        Misinterpreting a retraction of rising sea level predictions
        #21 shdwsnlite at 10:41 AM on 25 February, 2010: "What was the process?" Fitted least squares parabola to data (960121.rlrdata), coefficient of x^2 negative.
124633. Jeff Freymueller at 10:48 AM on 25 February 2010
        Misinterpreting a retraction of rising sea level predictions
        #18 Berényi Péter, their model sea level includes a response time in the differential equation that they solve. This deals with the fact that the response to a step increase in temperature would not be a step increase in sea level, but instead sea level would start to rise for a while, then level off after some time. It looks to me like they estimated this constant based on the fit to the last 22,000 years of post-LGM sea level rise (the details are in the supplementary material, not the main paper). This means that if there was no change in temperature starting in 1900, for example, you would still expect sea level to rise for a while because of past temperature changes, but the rate of rise would go down with time. So the 'new rise' is the response to the temperature changes of the 20th century. I find Rahmstorf's approach easier to understand, but the way, and it is probably more useful to discuss that approach. (Another time, at least for me, I need to log off here and get some work done). As for acceleration of sea level rise, you can see from Figure 3 of Vermeer and Rahmstorf that the rate of global sea level rise has increased with time (and this rate is faster than the average over the last few thousand years). Whether or not you can detect an acceleration in a single tide gauge record is really beside the point, as I said a few days ago.
124634. shdwsnlite at 10:41 AM on 25 February 2010
        Misinterpreting a retraction of rising sea level predictions
        @ 18 Berényi Péter..-- you posted: 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. How did you reach that conclusion? What was the process?
124635. 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.
124636. 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.
124637. 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.
124638. 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.
124639. 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.
124640. 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.)
124641. 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)
124642. 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.
124643. 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.
124644. 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.
124645. 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.
124646. 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.
124647. 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.
124648. 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.
124649. 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.
124650. 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.

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