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Comments 61801 to 61850:

  1. Prediction: New Surface Temperature Record in 2013
    Is there a need for an alarmist view on things to come wrt to the global temperature? I started writing something of the 'known unknowns' as an exercise, and I'm currently on track to get nearly double values for the 2013 or rather for 2014, some of the effects are just too slow. The exercise: To get maximum value for delta-T in short term predictions (2-5 years), one would have to argue for the suppression of the arctic (and antarctic) ice loss by the incoming currents (possibly by the THC shutdown mechanism?), while stating what the sudden ultra-large methane bursts would do. Additionally one has to make arguments of the continued rise of ocean surface temperatures (increased stratification) to get the maximum effect on temperature. Clean up of SOx in China and the lack of volcanic eruptions (because the world gets rounder with the glacier loss) would have an effect. And then there's the possibility of the solar cycle to continue for long since the sun had a long rest period (giving hydrogen more time to sink to the fusion layer of solar innards). All this while all the oil/gas pipeline networks have fatal failures for a solar flare so large the controlling circuits fuse together (here you might guess this is made somewhat tongue in cheek). The text has very little maths currently, so it's easy to read! I won't post it here though. Maybe nowhere, since it's an exercise.
  2. Prediction: New Surface Temperature Record in 2013
    Excellent post Dana. With the caveats you've noted, I think you're pretty close to being on target. Now how well can we predict how the skeptics will respond to a new record warmth in he next few years? My guesses as to what they'll say: 1) It was all ENSO and Solar 2) Continued recovery from the Little Ice Age 3) Reduced cosmic rays caused less clouds 4) The uncertainty monster had a fever 5) Urban heat island effects 6) Residual effects from the 1998 super El Niño 7) Mars is warming too 8) Can we talk about "Climategate" instead? 9) Who cares? Plants love it! 10) Isn't Monckton an awesome debater! Finally, while over the long-term, there is little doubt as too the direction of tropospheric temperatures in the 21st century, with or without a new Maunder- type minimum, and also little doubt as to the cause of that increase, I am still more interested in watching ocean heat content, and certainly hope we can get more readings at deeper levels very soon. The troposphere can be quite fickle with such a low heat capacity compared to the ocean. Whereas the ocean is both s better record of the past and is key to dictating how warm we'll be getting from our antropogenic experiment on our planet's energy balance.
  3. Prediction: New Surface Temperature Record in 2013
    From here, Dana1981 has put out a mid-line forecast for 2012. While some of the factors are treated aggressively, Cycle 24's dance with El Nino appears to be conservative. In contract to Dale 21 forecast, Cycle 24 is ready to roll. Hathaway's reduced forecast was partly a reaction to the screaming memee's yelling Dalton Minimum cooling. Hathaway's revised forecast But like many of the recent redacts and retracts, Solar Cycle may have a Cycle 23 punch in it - not never, just late. Spotless quiet days: Current Stretch: 0 days 2012 total: 0 days (0%) 2011 total: 2 days (<1%) 2010 total: 51 days (14%) 2009 total: 260 days (71%) (Source http://www.spaceweather.com/) And the sunspot activity is rising, not sputtering along - March is already beating Hathaways max 2 years ahead of his 'peak': Sunspot Activity Bar Chart Some volcanic activity would actually be a bit more good luck (put Tom Hanks and Meg Ryan under house arrest for the duration). The GHG concentration is primed for a combination with Cycle 24 and an El Nino - not only is warming back on, but the shallow ocean temp trend pushes up, and there's a lottery with the winning region getting a scorch. China hasn't been mauled yet ... they're due. Whattaworld - hoping for a volcanic surge and a La Nina ...
  4. Prediction: New Surface Temperature Record in 2013
    "but only rising due to AGW and solar peak (weak as it will be)" That's not very "skeptical" of you! So, you position is that GHGs do have an effect but go with mysterious GCR effect to reduce the rise. Well actually observing a link between a weak solar magnetic flux and cloudiness would change climate science. We shall see.
  5. Prediction: New Surface Temperature Record in 2013
    scaddenp @22 If I had to put figures on it, let's go with 0.53C for 2012 and 0.55C for 2013. I think SOI may still be a bit too high to indicate a moderate El Nino. If one does develop I think it'd be pretty weak. Personally I think we'll see a weaker La Nina than this last one, in the neutral zone, but still negative. I also think a weaker TSI and weaker solar magnetic flux will result in cloudier skies, which would only add to any dampening. Hence why I predict 'stead as she goes'. Spose it's not technically flat, but only rising due to AGW and solar peak (weak as it will be).
  6. Prediction: New Surface Temperature Record in 2013
    sauerj @20 - Figure 1 is the average of all 3, while Table 1 is just GISS.
  7. Prediction: New Surface Temperature Record in 2013
    Good for you Dale. Want to hazard some actual numbers for 2012,2013? I hope you are betting too. Should Dana turn out correct (which I am not hanging my hat on - I'd go 0.58 provided weak El Nino develops), how does that effect your skepticism?
  8. Prediction: New Surface Temperature Record in 2013
    You dared a sceptic to predict. Ok. I think we'll see a shorter than usual solar cycle. Currently, cycle 24 is progressing in start-stops, sort of like a car when you push the pedal to the floor, it accelerates then the cylinders skip and you stall. I predict this will continue throughout 2012 with a weak peak end of 2012/start of 2013. Flux is also indicating a weak cycle and early peak. Anyways, with that in mind I think TSI will not rise, but stay the same. With a weak sun this year, the trade winds will kick in over the Pacific (warm Atlantic, cool Pacific). If a La Nina develops as a result, it'll be pretty weak, weaker than the last. Overall with those points in mind I'm going to predict 'steady as she goes' with pretty much stable temps across the two years. After that it's anyone's guess. With predictions of a solar minimum (grand or not is yet to be known) we may see some slight cooling after 2013 for a couple of years. After 2015........ *shrug*
  9. Prediction: New Surface Temperature Record in 2013
    Dana, Very interesting! One question: The observed values in Table 1 don't seem to match the graphed values in Figure 1. The difference doesn't appear to be a consistent constant. Is this because Table-1 is only average of NOAA & GISS data, while Figure-1 includes HadCRUT data?
  10. Changing Climates, Changing Minds: The Great Stink of London
    Here's an image of a model calculation of a pulse of CO2 About half of the CO2 gets absorbed in the ocean very quickly (over centuries), another quarter reacts with calcium carbonate in seawater (over millennia) and the remaining quarter is removed by reactions with silicate rocks (over hundreds of millennia).
  11. Changing Climates, Changing Minds: The Great Stink of London
    PluviAL: I suggest that you read this general-readership article from Nature. The lifetime of CO2 in the atmosphere is not a concept that is either easy to understand or quantify and the notion is not very intuitive. I too, intuitively believed that all the emissions would be rapidly absorbed by natural processes. David Archer (cited in that article) summed up the consensus view succinctly in his book The Long Thaw as:
    The lifetime of fossil fuel CO2 in the atmosphere is a few centuries, plus 25 percent that lasts essentially forever. The next time you fill your tank, reflect upon this.
  12. Changing Climates, Changing Minds: The Personal
    Andy, yes indeed that name seems familiar, and the hosting organization fits perfectly. Thanks for filling me in, and for a thoughtful original post.
  13. Changing Climates, Changing Minds: The Great Stink of London
    I differ intuitively with similarities item f: It seems if the contribution of CO2 by civilization is 29 "somethings" and the planetary budget is 750 of the same "somethings" measure. That is: the oceans and plant life contirbute a far greater amount, than that the anthropogenic CO2 contiribution. If so, than it can esily be consumed by nature once fossil fuels stop being used. I understand the oceans storage is an issue, but the same mechamisims apply. To claim an effective life 12 to 14 thousand years seems incorrect. My intuition is that once we get past fossil fules, the problem is not so big. The problem is replaceing the huge wealth of energy stored in corbon, and too hard to rationalize, to the consuming public, taxing it. This is a sincere concern, any direction is appreciated.
  14. Changing Climates, Changing Minds: The Personal
    ianw01: That speaker would probably be Chris de Freitas. I attended a lunchtime talk given by him sometime in the 1990's (it may well have been the same one you went to) hosted by the Canadian Society of Petroleum Geologists. I too recall being a little shocked by his snarky attitude and the reaction of the audience. Had this been a talk on any other scientific subject, I doubt that the audience would have reacted the same way; it was most unprofessional. De Freitas subsequently, in 2002, published a paper in the Bulletin of Canadian Petroleum Geology. I have since learned that that paper was reviewed by Willie Soon and Sonja Boehmer-Christiansen, who were hand-picked by the journal's then editor, Tim de Freitas, Chris's brother. This particularly irks me because the Bulletin is otherwise a fine scientific journal. Earlier in the 1990's, I published a paper in the Bulletin and also acted as a reviewer. Because of the CSPG's unscientific and politicized stance on climate change, I choose no longer to be a member of the society.
  15. Prediction: New Surface Temperature Record in 2013
    Hi Dana, Interesting post. You are probably aware that the UK Met Office also issues a forecast for the global annual mean temperature, here is the link for those who are not familiar with their forecast. They are predicting that 2012 will be warmer than 2011, but not be as warm as 2010 was. I'll be bold and also make a prediction for 2012 using a simple analogue approach. Like others my assumption is that there will not be a major eruption the tropics loading the atmosphere with aerosols, and that neutral to weak El Nino conditions will dominate for the remainder of the year. Most current products are not predicting a moderate or strong El Nino at this time. Using the GISTEMP global surface temperature product my guess estimate for global surface air temperature anomaly for 2012 is +0.57 to +0.61 C, with a best guess estimate (very unscientific I know) of +0.59 C. IMHO, Dana's estimate of +0.65 C is at the very upper end of the possible range. So I very much doubt that 2012 will break the existing record (2013 is definitely a candidate though), but note that 2012 could be the first La NIna year which breaks the anomaly of +0.57 C set in 1998 following a super El Nino. If 2012 ties or breaks the anomaly set in 1998, that in its own right will be highly significant and disturbing landmark. So it could be an interesting year.
  16. Changing Climates, Changing Minds: The Personal
    Not to pile on the geology aspect, but my "moment" was in the mid 1990's when I was invited by a geologist friend to a talk by a noted climate change scientist at a luncheon hosted by a geologists' association. (If my memory serves me correctly the speaker might have been from New Zealand.) I went in eager to learn about the issue and was dismayed at his flippant attitude toward the possibility of humans having an effect. The lack of real in-depth data, and half-explanations left me shocked. But even more so, I was shocked by the receptive laughter to his jokes that mocked climate science. I only left with one conclusion: be very skeptical of so called "skeptics". Interestingly, I had another such moment years later visiting a web site associated with Tim Ball, who was cited in the local media. The half-true pseudo-science, clearly crafted to confuse people with minimal science background, was enough to prod me to do some real research, and SkS proved to be a credible source for me. I find it fascinating how I can credit the deniers for my climate science education. Well - more accurately credit to them and the SkS authors, who might or might not wish to share such credit!
  17. Prediction: New Surface Temperature Record in 2013
    I'm curious why Indian aerosol increases are seldom mentioned, but Chinese aerosols frequently are. (I have some Google researching to do...) I suspect that continued summertime Arctic sea ice loss will have an increasing contribution towards increasing global temperatures. Some projections of sea ice coverage suggest extreme reductions in the next few summers. More energy will go to increasing surface temperatures and less to melting sea ice. (My gut pessimism on Arctic sea ice, however, is proven to be unreliable.)
  18. Prediction: New Surface Temperature Record in 2013
    Wait. I thought Monckton et al had promised us that we were beginning a long cooling trend.
  19. ‘Storm of the Century’ to become ‘Storm of the Decade’
    Structures such as a port have to be built on the coast (obviously) but wouldn't it be more sensible to pull every other construction back from the coast rather than trying to build bigger sea walls. The same goes for flood plains. Turn areas that will be inundated into parks, wild life reserves, even sports grounds and simply avoid the problem. If you have been to Hawaii, for instance, you will see hotels with the front door right on the beach. That is just asking for trouble and spoiling what should be a beautiful area for recreation.
  20. Prediction: New Surface Temperature Record in 2013
    The probability of a new record rises with each coming year, but if the solar peaks in 2013, then it will still be above average for a year or two after that, during which time input energy is likely to be higher that output energy; so, whatever effect it has will continue to push temps higher. Depends a lot on the lag time, but much like it is hotter at 2PM than it typically is at noon, I suspect the next peak in temp will be some time after the next peak in TSI. If the ENSO was in a cool phase last year, then it should peak, assuming a 5 period, toward the end of 2013 or 2014. 2014 would coincide with my guess of max effect for TSI; so, I pick 2014 as the next year we are likely to see a larger than average temp increase. 'Course, next peak and next record are different measures, and aerosols, volcanic or industrial, could easily nix all that. Then again, declining summer sea ice could albedo-push it up. My two cents, probably worth every penny.
  21. Prediction: New Surface Temperature Record in 2013
    A new record will most likely be made in a few years. But most people fail to see how much the sulphur emissions have increased since 2000 (mostly in Asia). Climate cooling emissions from shipping have also increased. And since the emissions from ships are distributed across the world's oceans planet's reflectivity has increased even during recent years. Even rather dark particles are more reflective than ocean surface so aerosol cooling is especially effective off-shore (add the secondary effects on clouds and we get surprisingly big numbers). Do we have any evidence that China's aerosol emissions would be decreasing any time soon? Sulphur emissions from ocean-going ships are expected to decrease 2020 or 2025. We'll surely make some impressive new records when aerosol emissions really start decreasing.
  22. Monckton Misrepresents Reality (Part 3)
    @Alex C: The SkS system automatically generates a single daily email alert about all of the articles posted on a given day. You are correct. One does have to sign-up for this service. To the best of my knowledge, there have been no glitches in this system since it was created in mid-2011. Prior to that time, an email alert would automatically be generated each and every time an article was posted.
  23. Prediction: New Surface Temperature Record in 2013
    Actually GISTEMP LOTI has 0.35 and 0.40 for Jan and Feb 2012. So we have to average close to 0.7°C anomalies the rest of the year to break the record. Doesn't seem likely.
  24. Piet R. Zijlstra at 03:50 AM on 13 March 2012
    Changing Climates, Changing Minds: The Personal
    Since the first Club of Rome report –this month exactly 40 years ago – I recognized the exponential growth principle. Working in the chemical industry I was indeed confronted with depleted resources and/or much higher costs of energy and raw materials. Also in 1972 deniers acted against the Club Of Rome message. And I recognized that the denier-message was much easier adsorbed by colleagues and friends. Although most of them actually did not buy or read the report! It made me angry! With the concept of exponential growth in mind I looked to the global population figures. Four (4) billion in 1974, with growth factor 1.75 to 7 billion in 2012. (I cannot coop with the label of “overpopulation”). The next area is the use of fossil fuels. The concept of Peak Oil is clear. The unavoidable energy transition did only recently start. Many renewable energy production or conversion systems are short after start-up in “death valley”. Development is hampered by to small scale operations, NIMB-actions of citizens, too high costs and severe energy storage and distribution problems. At this moment I do not detect the right urgency in the main press. Going with the use of fossil fuels we earn the CO2-problem. The last six months I studied Climate Change. I came to the conclusion that mankind is actually doing a geo-engineering process. The atmosphere and oceans do change in composition. And it cannot be avoided and the effects are not clear at all. After reading on skeptical and denier blogs and following the main press I had at a weak period in my thinking. They got me almost in their camp! I really needed to study the science again and again to know where my believe should be based: in the scientific approach. Recently I choose to do a study on scientific thinking. My focus is communication of climate change to the public. Actually I am still angry and want to use the adrenaline shot in a positive way. The SkepticalScience website has been of great help in forming my opinion.
  25. Prediction: New Surface Temperature Record in 2013
    If 2013 is +.76, that will be a really hot year. Even if the next few years after are cooler, it will still be harder for skeptics to claim warming has stopped. One very hot year per decade with several that exceed the previous decades hottest year make the trend pretty clear. 2012 is starting out pretty cool with Jan at .40 and Feb at .51. Ten more months to go, but it will take some .7's to bring up the average.
  26. Prediction: New Surface Temperature Record in 2013
    Tom - yes, perhaps it would be more accurate to change the 'CO2' column to 'other', and 0.02 to 0.017. But it's a small difference. Coincidentally, there's also a very good chance that 2012 will be the hottest La Nina-influenced year on record, though it might not technically qualify as a La Nina year per the WMO criteria in Figure 1. What would really be interesting would be if there is an overall negative ENSO influence on the 2012 temperature anomaly, and yet it still ties or breaks the record, as will be the case if my prediction is correct.
  27. Prediction: New Surface Temperature Record in 2013
    First time poster, long time lurker, and a veteran of "climate wars" in the blogosphere... Coincidentally, I made almost the exact same bet on a record in the next few years at Zerohedge.com, I did qualify with the caveat that there be no major volcanic eruptions... Anyway, I would like to thank the authors of this blog for my making my defense of AGW so much easier... If you would like to have real fun, try hanging out at an unmoderated financial website dominated by right wing libertarian types... Believe it or not, I feel that is the real frontline in the AGW debate...And the debate is not for the feint of heart...Over time there is a growing minority, even at such sites that knows AGW is real, but are actually afraid of voicing their opinions for fear of ridicule... The recent FR2011 and Hansen papers are exactly what is needed in this debate... They are clear irrefutable evidence that the climate is changing and my two biggest clubs in the battle against ideologically driven denial... Don't laugh, it is a war out there.... PS My background: Ph.D. physics, 20 years in academia followed by 5 years on Wall St....now semi-retired...
  28. Prediction: New Surface Temperature Record in 2013
    dana @8, the 0.017 C per annum is the residual trend in GISTEMP when the influence of MEI, TSI and AOD have been removed by Forster and Rahmstorf's method. Therefore it is the contribution of all other factors to that trend, including all GHG, Aerosols and any long term natural oscillation (if any). The Chinese have been cleaning up their aerosol emissions, so that may be a good reason to think the underlying trend will increase in the near future, but based on the evidence of the last 40 years, with all factors included it is just less than 0.02 C per annum. I am less skeptical that 2012 will break the record. My gut suggests that 2012 is more likely to be in the upper half of the uncertainty range, and 2013 in the lower half. But guts are notoriously bad predictors, so I'll stick with my tweaks on your prediction (for stated reasons).
  29. Prediction: New Surface Temperature Record in 2013
    Makes sense, and it certainly got me curious enough to keep my eyes on GISS global temps to see how it turns out.
  30. Changing Climates, Changing Minds: The Personal
    Doc Snow@36 Very similar experience to mine. A contrarian acquaintance of mine was in the habit of posting long messages full of damning evidence on an IRC channel that we both frequented. At the time my acceptance of AGW was based mostly on my general acceptance of science and not on any particular strongly held conviction so his barrage of evidence forced me to really investigate what he was saying and what I believed. The first thing I discovered was that he was not performing the same level of investigation as his source often contradicted his premise. After a few months of him posting some nail-in-the-coffin-of-global-warming, me actually reading it and replying with facts, and him calling me a socialist stooge (no joke) I gave up arguing with him.
  31. Steve Metzler at 02:29 AM on 13 March 2012
    Peter Sinclair interview with Michael Mann
    Unfortunately, that interview was about 2 mins shorter than it needed to be to get an important point across about the Wegman Report. It's not the plagiarism in the WR that does the most damage to the layperson's viewpoint of the usefulness of paleoclimatology, but rather the fundamentally flawed statistics, as detailed here: Replication and due diligence, Wegman style Wegman accepted McIntyre's flawed and cherry-picked PCA analysis without doing the slightest bit of due diligence on it. In short, the WR was a colossal stitch-up of MBH98 using way over-persistent red noise to generate the random time series, then cherry-picking the top 100 most hockey stick-like PCs from the 10,000+ simulation runs. This Wegman/McIntyre stitch-up is described in Mann's book (which I just finished reading this morning), but alas, did not make it into that interview.
  32. Prediction: New Surface Temperature Record in 2013
    Tom - yes, the CO2 influence should be closer to 0.017°C, but don't forget there are other GHGs as well which will add a small warming contribution, though they may be offset by aerosols. It's all just a rough estimate, and +/- 0.1°C looks to be a good estimate of the margin of error, which again suggests a very good chance that 2013 will break the record. Like Kevin, I'm skeptical that 2012 will break it, but we'll see. It mainly depends on that El Nino.
  33. Prediction: New Surface Temperature Record in 2013
    Michael Sweet @5, you are correct, my bad. However, given the way Dana sets his prediction up in Table 2, the difference is 0.003 C in 2011, 0.006 C in 2012, and 0.009 C in 2013. That would suggest my predictions should be: 2012: 0.64 C (having rounded down) 2013: 0.76 C (- 0.01 C for the lower anthropogenic increase, plus 0.01 C for the expected understatement of the effect of the El Nino).
  34. Glenn Tamblyn at 23:50 PM on 12 March 2012
    2012 SkS Weekly Digest #10
    Thanks John for the plaudit. But simply, poetry is one of those things that we should be focussing our attention on. Where Climate Change is concerned, one of the most important but least recognised impacts is the cultural losses that might ensue in a climate stressed world. The poems that might be lost. The old languages that vanish because a local indigenous population can no longer survive and still keep their culture intact. Not all culture originates in a Shopping Mall. And we are the custodians of all that has gone before us. The more we pass on to the next generation, that they may add to it, the richer our childrens lives are. And the richer our lives are. Civilisation is always about taking the past, adding to it and buiding upon it. But never throwing it away without VERY good cause!
  35. Prediction: New Surface Temperature Record in 2013
    Tom: I tried adding an MEI squared coefficient. The coefficient is positive but very small: 6*10-3, std error almost as big, p~18%. Visually the result is indistinguishable from the original. 3rd and 4th powers are less significant still.
  36. michael sweet at 22:02 PM on 12 March 2012
    Prediction: New Surface Temperature Record in 2013
    Tom, I think you mislaid your decimal. Dana would only be .003C off with his rounding. That would not affect his 2012 projection and would only lower 2013 by .006C. Hansen had a prediction similar to this 5 or 6 years ago where he said he expected a new record within three years. The next two years were La Nina years, but the third set a new record. I like Dana's method. We will have to see what El Nino does in the next 18 months. It is surprising that 2012 comes out so warn after the relatively cool January.
  37. Prediction: New Surface Temperature Record in 2013
    Tom: No idea, because my numbers aren't based on a model. I'm grafting together the aerosol correction from my model, which gets the solar term completely wrong, with the mean of Arthur's and Dana's which gets it right. In other words a guess based on my intuition and mangled data. Don't read anything more into it than that! Here's some brainstorming for your missing ENSO signal though: 1. See if the ENSO fit can be improved by doing the F&R correction as now, and then looking at the lagged correlation between the MEI and the residuals to look for any residual ENSO signal at differrent lags. 2. Try and handle non-linearity by adding a term which is quadratic or cubic in MEI. The latter is pretty easy. I might try that.
  38. Prediction: New Surface Temperature Record in 2013
    Kevin C wrote: "It will be interesting to whether any 'skeptics' respond." Given that 2013 is the next sunspot maximum, I'm sure that the deniers will attribute record warmth to the sun if these predictions come through. If the temperature for a few years afterwards hover around 0.6-0.7C, we will have a new round of "look, it's stabilized".
  39. Monckton Misrepresents Reality (Part 3)
    funglestrumpet @16: Thank you for the notification - I was under the assumption that the daily email service had slightly changed (I for one am no longer getting emails, I think it is a something you select for?), but I'll pass on your comments.
  40. Prediction: New Surface Temperature Record in 2013
    For what its worth, I notice that Dana uses 0.02 C per year for the influence of CO2 (really the combination of anthropogenic factors). Based on Foster and Rhamstorf, however, the the global warming signal measured by GISS is 0.17 C per decade. Therefore I expect Dana has overstated the temperatures by 0.03 C degrees, leading to a prediction of 0.62 C for 2012, and 0.73 C for 2013. I have notice before that the Foster and Rhamstorf regression does not capture the full influence of ENSO, leaving a residual ENSO correlated signal after the regression. Therefore, allowing or this I would adjust the 2013 prediction up slightly, to 0.74 C. I notice that Dana's method has had errors of 0.07 C twice in a decade. Based on that, I doubt the accuracy of projection is much better than +/- 0.1 C. It would be significantly worse as a prediction because of the error in predicting ENSO and volcanic eruptions. I notice that both Dana and Kevin C mention the margin of error, but so far as I can see, they do not specify it. I would be interested in their specification of the margin of error on condition that their are no major tropical eruptions and that there is a moderate El Nino in 2013.
  41. Radiative Balance, Feedback, and Runaway Warming
    Michele #94, it took me a while to read enough wikipedia thermodynamics to acquire a fair amount of (first approximation) confidence in your 3 primary equations; however, there were details I could not accept (as covered below). This comment is only on part 2 (no clouds). First, I'll briefly note my interpretation of the 3 equations. >> xTt^4 + (1-x)Ts^4 = Tef^4 The power .jkljkljkljk [I'll finish this answer later] >> Tt/Ts = (Pt/Ps)^(R/Cp) Assumption: the temperature up and down the atmosphere is the result we'd get if there was no vertical convection. I think this is the hydrostatic equilibrium, which can be described (I think) as: the temperature at all points exactly match the potential temperature of a single reference temperature, so I think this means the entire atmosphere in this region would be at the same temperature if we factor out the lapse rate ... or at least that is the assumption for the two points "surface" and "toa". >> Ht = (Ts-Tt)Cp/g Assumption: The hydrostatic equilibrium applies. This is just an application of the lapse rate. >> P=.2 bar Why? I'll assume for the moment that it is because the atmosphere above this point (@300ppm,Ht,Pt) absorbs radiation below some threshold value. Clearer insight into this would be welcomed. I expected appeal to data (like Hottel CO2 absorption) or to Beer Lambert. >> xTt^4 + (1-x)Ts^4 = Tef^4 >> ‘x’ is the % of radiation in the CO2 bandwidth, ‘(1-x)’ the remaining radiation in all the spectrum >> x=.04 What is x? Why .04? Doesn't CO2 absorb a much larger part of the spectrum? I would think x, as you define it (but not as used in the Stefan-Boltzmann based equation) is closer to .2 based on Hottel measurements and probably/hopefully agreeing with analysis of line spectra for CO2. And I heard that satellites measurements indicate that close to half of the IR radiation from the planet reaching the satellites is in the CO2 range, suggesting that maybe that x value should be closer to .5 as used in the equation. In any case, where is the derivation of x or where does its measurement come from? >> Tt/Ts = (0.2/90)^(299/1043) = 0.287 That math comes to something different: 0.1735 .. as can be easily verified by copy/pasting into google search bar. The 299, 1043, and 90 are in the right ball park (and I already wondered about the .2). >> If x << 1, then is Ts = (1+x/4)Tef Can you give me more insight into this simplification (we are dealing with almost insignificant digits perhaps, but I am curious where the approximation comes from)? I don't see why we need an approximation since we have 2 equations and 2 unknowns (Tt, Ts), and one equation is linear so one variable can easily be eliminated for substitution. Given Pt=.2, Ps=90, R=299, Cp=1043, and using your Tt/Ts=...=.287 which might be wrong, we get for the first equation: x(.287*Ts)^4 + (1-x)Ts^4 = Tef^4 or, after substituting x=.04 and Tef=240: Ts = (240^4/(.04*.287^4+.96))^.25 = 242.4 (as you got). So using your .287 (instead of .1735), I get the same thing you got but without having to invoke the alleged approximation. >> Ht = (1+x/4)(1-0.287)(1043/8.87)Tef/1000 = 0.0838(1-x/4)Tef kilometers. You did not pass on the (1+x/4) .. you changed it to (1-x/4). Ht = 0.0838(1+x/4)Tef >> Ht = 0.082Tef With the above fix, we get Ht = 0.0846Tef >> Ht = 0.082Tef ..= 15.6 Km 240 * .082 = 19.68 Km However, after the fix to the equation, Ht = 0.0846Tef = 20.31 Km This is the same thing we get without having to use the approximation. Ht= (Ts-Tt)*Cp/g = (242.4-69.6)*1043/8.87 = 20.32 Km although this does rely on the .287 ratio that might be wrong. All of the above rely on the x=.04 which appears wrong based on how I interpret your definition and/or use in the equation. If you get back to this thread, can you try to answer some of the above, as I think the model is probably decent but there appear to be mistakes? Thanks again for the detailed candidate solution to Venus with 300ppm CO2 (and presumably the rest of the atmosphere along similar percentages as Earth). I won't deal with "3) Clouds" right now since you reused x=.04; however, the model you used there is also interesting, so I will study it even if you don't return to the thread.
  42. Prediction: New Surface Temperature Record in 2013
    It's a bold prediction. I agree with the approach - having come round after arguing against it for a long time. I still think the uncertainties in the scale of the exogenous factors are understated. Here's my prediction: 0.61 (2012) and 0.70 (2013). Why? I'm betting on my own rerun of F&R's calculation with a response function to spread the effect of the exogenous factors over a longer period, and a ramp function from 2000 to simulate increase aerosol emissions. However, the fit on my model is poorer than Tamino's, and the p-value on the ramp function is only 18%, so I can't really claim any evidential support. It's also a coward's bet given that I am on the conservative side for both years, and even if I were to get it right the error bounds are sufficiently large that it wouldn't actually offer any support for my model. It will be interesting to whether any 'skeptics' respond.
  43. ‘Storm of the Century’ to become ‘Storm of the Decade’
    Today, a “100-year storm” means a surge flood of about two meters, on average, in New York. Roughly every 500 years, the region experiences towering, three-meter-high surge floods. Both scenarios, Lin notes, would easily top Manhattan’s seawalls, which stand 1.5 meters high. But with added greenhouse gas emissions, the models found that a two-meter surge flood would instead occur once every three to 20 years; a three-meter flood would occur every 25 to 240 years.
    I raised an almost identical point at a local council public forum on climate change about six years ago. The engineers had prepared quite a good plan for future council policies and strategies to avoid or to ameliorate the consequences of sea level rise for low-lying suburbs. However, they presented their calculations, graphs and maps based on 1-in-100 year storm events. At the end of the presentation I stood and asked why they used a current 1-in-100 year storm event definition, rather than estimating current and future changes in frequency of flooding to various levels above the current Australian sea level datum, given that 1-in-100 year event frequencies would change over time, and given that such changes would impact on Council responses to sea level rise. The engineers stared at each other for a while, and then one of them admitted that they hadn't thought of that. The embarrassed silence that followed was palpable.
  44. Changing Climates, Changing Minds: The Personal
    I arrived at SkS from, quite frankly, a fairly random web search a couple of years ago. I've always been convinced of the evidence for AGW - it simply makes sense to me that our actions have consequences, and I (personally) didn't need convincing of that. Once here, I was rather amazed at the logical perambulations required to deny the science - the posters who were just blowing smoke, so to speak. The lack of logic, the stacked fallacies (I have a background, among other things, in philosophy), the self-deception required to flatly deny the evidence - it's incredible, and horrifying, to me. And so I've begun to opine on the subject myself, in the hopes of a useful contribution. Since then I've also sought out some of the 'skeptic' blogs, pointing out facts where I can, where I feel I might have an impact. And (where I can) attempting to contribute to the discussion here. SkS has been an amazing resource in this regard; it's my hope that this information, when spread widely and clearly, may lead others to a more reasoned evaluation of the evidence. It's going to be a rough ride for our children, our descendants, due to our actions. I can only hope we can act, in a reasoned fashion, to minimize the problem...
  45. Changing Climates, Changing Minds: The Personal
    No one totime has suggested SkS link in the process of "eye-opening" for many "lukewarmers" so I will do. Until I started reading SkS (middle of 2011) I was indifferent to the arguments for AGW, me opinion more or less formed by number of articles in popular press that I've heart to be "for" vs. "against". Even Al Gore movie, which should have "opened my eye", like in Dana's case, did not really convince me, because of its subsequent critisism by "skeptics". When I started reading SkS and checking their references/verifying with my knowledge in some subjects, I realised that popular press bias is bad choice for formulating one's opinion on AGW issue. Especially when I compared the clarity of SkS resources and obviousness of their arguments (as opposed to obscurity and complicated language of "skeptic equivalents such as WUWT) I started appreciating how good job SkS is doing at popularising climate science. Eurica price diplayed on the right margin is well deserved.
  46. Changing Climates, Changing Minds: The Personal
    I was 'converted' from a lazy, casual, lukewarmish acceptance of the mainstream science by denialists on a local chat group. They'd throw out one of the usual memes. I'd be amazed. I'd ask, "Can this possibly be true?" Then I'd diligently root around and find out that, no, it's not true. After a while the pattern became obvious... and it became obvious as a corollary that all this bunkum wasn't just spontaneously generating itself, like bacteria were once supposed to do. It was seeded and nourished by organized groups, in service of an agenda--or, I think now, a couple of interlinked agendas. Call it the Germ Theory of denialism, or call it a war on truth. Just don't call it coherent, because it always turns out not to be, if you look.
  47. We've been through climate changes before
    Thanks for the comments, and welcome to visitors from ClimateProgress. I've added a list of references which can answer many of the issues raised above. The temperature data on John's image can be found in the Hansen and Sato paper. I'll check with him about adding a T scale.
  48. ‘Storm of the Century’ to become ‘Storm of the Decade’
    muoncounter--most nations seem to have just a few; only a handful have double digits-worth of 'resilient cities.' The top five, if I'm not mistaken: 5) Serbia (49) 4) Lebanon (56) 3) Phillipines (107) 2) India (118) 1) Austria (272!) Seems the future may speak German.
  49. James Hansen's Motivation
    Agnostic @10, Does anyone disagree? Is it the rhetoric question, especially given the opinions of commenters 1-9 before yourself? I can perhaps say that James' suggestion of 5m of SLR in this century is a bit exaggerated. Technically, it will be less than a metre until 2100. But uncertainties of upper limit are huge. It may well be that we are already committed to 5m+ if not in 2100, certainly in equlibrium a few centuries later. That's still a moment on an athopogenic scale. So I don't blame him for that.
  50. ‘Storm of the Century’ to become ‘Storm of the Decade’
    An interesting effort by the UN World Disaster Reduction Campaign is called 'Making cities resilient.' Their map shows the 982 local governments around the world that have signed on to this campaign. There are exactly 2 in the US (and neither of those are coastal cities). I seem to recall a fable about an ant and a grasshopper. The one that survived was the one that prepared for survival. Oh well.

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