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Comments 49451 to 49500:

  1. NASA Retirees Appeal to their Own Lack of Climate Authority
    Concerning Mr. H. Leighton Steward, the spokesperson for this group, I have also witnessed his efforts in Montana on behalf of our state's fossil fuel industries in order to discount the perils of CO2 emissions. Mr. Steward now presents himself as a scientific expert on the subject of climate change. He is, in fact, the Director of EOG, a gas and oil company formerly known as Enron. He is also the spokesperson for a fossil-fuel advocacy group called Plants need CO2, whose advertisements have been shown frequently throughout Montana. On June 9, 2010, he provided the citizens of Billings and the students of MSU Billings with a presentation sponsored by the Montana Petroleum Association, the Montana Chamber of Commerce and Big Sky Economic Development called Our atmosphere needs more CO2. For your inspection, his basic message can be found in 2010 issue of the Montana Treasure State Journal, the official publication of the Montana Petroleum Association, pages 28-32 (can be seen on the Web at: montanapetroleum.org/assets/PDF/articlesReports/2010-Treasure-State-Journal.pdf.) In all of his presentations, Mr. Steward assures us that the Earth’s temperature can increase by only 0.2 degrees C or less - even if we let carbon dioxide (CO2) levels increase .without constraints during the rest of this century and into the next. Thus, he is claims that the sensitivity of CO2 will always be less than 0.2 degrees C, even after CO2 levels reaches 1,000 ppm ! As can be seen in the article referred to above, Mr. Steward bases his version of "happy science" entirely on a century-old, over-simplistic theory that was discarded many decades ago by both theory and direct observations. His model is of no relevance to the real world because it accounts only for the absorption of infrared radiation by the greenhouse gases and does not also include the emission of this radiation by these same molecules within the atmosphere. Even Svante Arrhenius know better way back in 1986 ! In short, the leader of this group is a classic, oil-saturated pseudo-scientist doing his best to keep the oil flowing for as long as possible. Eric Grimsrud (web site at ericgrimsrud.com)
  2. NASA Retirees Appeal to their Own Lack of Climate Authority
    This sort of denialism seems to suffer terribly from short term thinking. I'm forced to conclude that they are concerned about their retirement, but not the quality of life for future generations. While CO2 levels continues to rise, coherent long term thinking about the inevitable implications, underpinned by basic physics, is sadly lacking. (Present company excepted!)
  3. NASA Retirees Appeal to their Own Lack of Climate Authority
    The stuff presented by this bunch so far shows exceedingly strong symptoms of denial. They say their objectives are to "determine to what extent human-related releases of CO2 into the atmosphere can cause earth surface temperature increases that would have unacceptably harmful effects" which is a laudable mission. But even in the Introduction to their mission, they are pre-empting their own work. On the strength of the existence of "competing points of view" that they consider to be a "professional conflict, they jump to the conclusion that "nations have prematurely accepted the AGW advocates points of view and conclusions as correct." In their belief actions to address AGW are misplaced unless we can be "certain of the reality of the conclusions on this subject." The quote from their Overview's conclusion in the SkS post above is remarkably also present in the Introduction to the same document! There they also say that reducing our CO2 emissions "may be trying to solve a minor or even non-existent future problem." Not a word that it is more likely to be a very major possibly-catastrophic future problem which their do-nothing policies will bring about. All strong symptoms of denial.
  4. littlerobbergirl at 22:13 PM on 25 January 2013
    NASA Retirees Appeal to their Own Lack of Climate Authority
    The problem is its an appeal to authority that actually works. I see 'NASA scientist' or particularly 'astronaut' and I get an involuntary physical response - tight throat, tear in eye, that weird chest feeling that is love and hope and happiness. I see earthrise, floating lady astronaut in cloud of hair, space walkers, tatooeen, I hear 'one small step', the music from 2010.. It bloody works! These are my childhood heroes. I feel betrayed.
  5. NASA Retirees Appeal to their Own Lack of Climate Authority
    The organizer of this letter claims that 20 scientists contributed. Since they have not listed who they are, how can I know they are telling the truth? If they really have 20 people they need to tell us who they are. I could write a letter and claim 150 people back me up. Evidence of hteir claims is required.
  6. 16  ^  more years of global warming
    More proxy data. Available with no paywall is tree ring reconstruction and prediction results of Gray, et al in Geophysical Res. Letters 31, 1994, L12205; URL LINK 1. Calibrated tree rings versus known records during instrumental period, extended results into earlier times. Wind up with essentially a three dimensional graph (third dimension by color) between period, power, and year. 2. Most "power" appears between 40 and 70 years. Clearly, if real, this thing is no clean "70 yer cycle." One take home message, this. 3. The hair raising statistical unapproachability of such studies for the non expert is emphasized by the statement that they use a "multi-tapered method coherency spectra --- based on MTM analysis using red noise assumptions."
    Moderator Response: [RH] Hot-linked URL
  7. NASA Retirees Appeal to their Own Lack of Climate Authority
    [...] comprised of renowned space scientists with formal educational and decades career involvement in engineering, physics, chemistry, astrophysics, geophysics, geology and meteorology. Many of these scientists have Ph.Ds.
    Oh, a Ph.D, is that all it takes? In that case, time to go back to school and get a Ph.D in musicology. Then I'll be just as qualified to comment on climate science as this lot. It's particularly sad to see this kind of credential-burnishing (as if a Ph.D, in and of itself, mattered in establishing one's credibility as a subject matter expert or authority) as it's a reliable indicator, at least in my opinion, of crank-style argument, if not outright crankdom. It also IMO shows up the difference between the illegitimate and legitimate appeal to authority in scientific matters: the former is a substitute for satisfactory evidentiary support, the latter is a complement to it.
  8. Bert from Eltham at 15:44 PM on 25 January 2013
    NASA Retirees Appeal to their Own Lack of Climate Authority
    I am a retiree from CSIRO. Even six months away from keeping up with Structural Molecular Biology did leave me somewhat in the dark. I could no more comment on the latest findings in Structural Biology as it is now nine years since I retired and that is an eternity in our field. I can only be an informed spectator now, not a participant. Us burnt out old Physicists should listen carefully to all the evidence from young whippersnappers like Dana and then ask more questions as we are stuck in our cognitive thinking in a world that we think is real. It may not exist anymore! What part did these retirees from NASA play in all the failed missions? Just asking. Bert
  9. NASA Retirees Appeal to their Own Lack of Climate Authority
    I wonder how many of these anonymous NASA retirees worked in the assembly unit or were system engineers? Why is it that many people who call into question the established data sets turn out to have vast experience in engineering...? Is this about all about jobs and the paradigm of current industries? Where are the engineering futurist?
  10. NASA Retirees Appeal to their Own Lack of Climate Authority
    "Honest and reasoned discourse, we have a problem!" "That's one small meme for the denial'o-sphere, one giant misrepresentation of the science by retirees who don't actually work within the discipline for mankind." This is where Walter Cronkite removes his glasses and weeps.
  11. Lessons From Past Predictions: Ridley vs. IPCC and Hansen
    Philippe, Doug: Then again, some people think that "critical thinking" is bad... vis-a-vis the GOP in Texas: Texas GOP Rejects Critical Thinking Skills Can't have those innocent kids thinking for themselves, can we? Another more recent example from the same state [of mind]: Teaching Bible as Fact
  12. Doug Hutcheson at 12:52 PM on 25 January 2013
    Lessons From Past Predictions: Ridley vs. IPCC and Hansen
    Philippe Chantreau @ 5, the average ability of the population for critical thinking is probably about as it always was. The problem is that we have mass media shaping public perceptions and the mass media is not there to give consumers accurate, or fair, reporting of issues. There is no profit in truth, it seems.
  13. Subcap Methane Feedbacks. Part 4: Speculations
    wili: I do recall that Shakhova was quoted saying something along those lines. But I think that there is considerable uncertainty about whether methane clathrates exist at very shallow depths on the ESAS and if there are clathrates there, but at greater depths, how the extra heat will penetrate suddenly to those depths to destabilize them. All that I have tried to show in the article is that there is evidence in the Laptev Sea that indicates that there is some fossil gas escaping through thick permafrost there. For all I know, that fossil gas could be in the form of methane hydrates below and/or within the permafrost. How much methane will be released from the ESAS and how quickly it will be released needs to be answered by further research, not by further speculation, at least not by me. It's obviously a big concern, though. As for how others are responding to this, I can't say. Joe Romm is certainly not happy that the IPCC Fifth Assessment Report will not include "the potential effects of the permafrost feedbacks on global climate". I would agree with Romm that this is very disappointing.
  14. NASA Retirees Appeal to their Own Lack of Climate Authority
    This also begs the question: How many retired NASA scientists are there? NASA currently has 18,000 employees. They've been operating since 1958, so that's 55 years. Best I can gather there are something upward of 10,000 people who've retired from NASA over the years. So, this is coming from 0.2% of the retired scientists from NASA. You'd think if this was important (or merely even correct) they'd be able to muster larger numbers.
  15. Subcap Methane Feedbacks. Part 4: Speculations
    IIRC, Shakhova, whom you cite above, claimed in a lecture slide that 50 gigatons of methane from clathrates may be suddenly at any time. Am I wrong? Was she wrong? Or are you wrong? In any case, the combination of all three sources of methane (and CO2) you discuss here is certainly plenty to be worried about for the short and the long term. In particular, the MacDougal article you link to (just above your wonderful graphic) shows pretty clearly that permafrost emissions alone have likely already put us into a 'runaway' condition, where CO2 will continue to rise for a long time, no matter what we do. To be clear, I still think that means--more than ever, actually, that we should dramatically cut back on all ghg emissions. I've stopped flying, most driving and meat eating, have been active on a number of levels, and am considering civ disob this Feb. How are others responding to these news?
  16. Nature Confirms Global Warming and Temperature Record Accuracy
    Tron: Two old sayings (just to get started on an up-beat pace) - a person that has one watch always knows what time it is. A person with two watches is never quite sure. [They won't agree - which is right?] - when two measurements disagree, the most you can say is that at least one of them is wrong. [Both may be wrong.] ...but, to dissect the statement you are asking about, first let's consider the part that says "confirms the general accuracy of". The accuracy of the thermometer-based temperature record can be examined by looking at the details - the calibration of thermometers, placement, exposure (e.g. protection from radiation errors, etc.), regional sampling errors, etc. This has all been well-studied and overall the results are good. People keep studying this, and keep making tiny adjustments to methods of correcting known or newly-discovered errors, but these effects tend to be small. This tells us that the results are reliable. But how do we do another check? If you set up the same type of thermometers, in the same places, with the same exposure, and the same regional sampling, then getting the same result is not going to make you all that much more confident. [As an aside, that is why the BEST project is not considered by many to be ground-breaking: it's just a new way of combining the same numbers - a new mathematical combination. Contrast that check with another: one that doesn't use thermometers, uses different places, with different exposure issues, and different regional sampling. If this comes up with a different result, then you might say "hmmm. I wonder what is going on? What time is it, really?" One possibility would be that the instrumental record has larger errors than we thought. On the other hand, if it comes up the same result, then you are going to think "hey! This seems pretty robust. A completely different approach, yet it still shows the same trends. Perhaps we really do know what time it is!" Note the statement in the yellow box: "that the warming trend in the [instrumental temperature record] is supported by independent evidence." The "independent" part is important. Yes, it confirms the usefulness of the proxy, because we already had confidence in the instrumental temperature record. But it also increases confidence in the instrumental temperature record, because the proxy was developed independently. We're not making a copy of the watch, or calibrating to match the watch - we're determining time from something completely different, and coming up with the same answer.
  17. Nature Confirms Global Warming and Temperature Record Accuracy
    Tron Carter @8, you are exactly correct. The non-instrumental record is less reliable both because individual proxies respond to environmental factors in addition to temperature, and because the combined record has very few proxy series. Consequently there is very good reason to consider the instrumental record more accurate. However, for political reasons some people doubt, or purport to doubt, the accuracy of the instrumental record. This study is interesting, therefore, in that it shows their doubts for what they are - political posturing. It is also scientifically interesting in that it determined the temperature record without calibration. This holds the prospect of developing paleo-proxy series to determine past temperatures relative to modern ones without vexatious issues related to calibration.
  18. Nature Confirms Global Warming and Temperature Record Accuracy
    Hi everyone. I'm a long time reader, first time commenter so please... go easy on me. :P I have a question about the assertion made by this post's title and reworded in Dana's summary with the following statement:

    "The strong correlation between the two datasets confirms the general accuracy of the instrumental temperature record."

    This seems backwards to me. Of course, uncertainty exists in both types of datasets. However, isn't there greater uncertainty in the various proxy records than in the GTS and therefore this particular correlation would instead primarily strengthen confidence in the usefulness and accuracy of these proxy records? Am I wrong in thinking that the GTS is more robust than these individual proxy records? Maybe there is something else that I'm missing? I'm genuinely open to each possibility. Just trying to understand. Regardless, the figures are compelling and, assuming the methodology is robust,** the results do seem to lend even more credence to these types of proxy records... and secondarily, further verifying the instrumental record. ** Not trolling with the methodology comment. There's no reason to think otherwise but I'm always cautious to accept results without having seen the data myself. That's just how I roll. ;)
  19. 16  ^  more years of global warming
    curiousd @109, the wavelet analysis shown in Figure 2 b of Shanahan09 shows a 40 year period from 500 to 300 BC, then again from 100 to 200 AD, and again from 1000 to 1200 AD, and finally, just briefly around 1950 AD. I will leave aside my doubts that any mathematical analysis can show a genuine 40 year periodicity in a 10 year period. Instead I will focus on the very transient nature of this periodicity. Tamino has analysed similar attempts to find AMO periodicity in paleodata. His main point is that in picking out statistically significant periodicities, you need to allow for the fact that you are examining so many periods. Given essentially random fluctuations, if you examine enough periods you will find some during which, just by chance, the fluctuations will appear to be periodic with a given frequency. That is not significant unless the apparent periodicity is persistent. Ignoring the large number of periods examined is like making a hullabaloo over discovering a sequence of three dice rolls in a row where you roll a six and ignoring the fact that it occurred as part of a sequence of 100 throws over which the mean result was 3.5 and the rolls follow a poison distribution. It seems probable to me (although I have not, and cannot do the maths) that this very episodic 40 year periodicity will fall to the same criticism.
  20. Lessons From Past Predictions: Ridley vs. IPCC and Hansen
    Would it seem presumptive for climate scientists to criticize how the finance sector makes its predictions? If so, then why is the reverse so routinely accepted? We're in the middle of Great Depression II, which was led by the finance sector, which obviously misinvested large sums of 'money' it didn't really have. Beside formal government bailouts, Central Bankers are buying bank T-bills with made up money in the vain hope these financial wizards still know how to make proper investments in the stock market, which will 'trickle down' to the rest of the economy. That's the background for these same wizards claiming to school climate science about its conclusions, while their flagship news-magazines confidently claim that 'Fossil Fuels Green the Planet'. I'm going to have to reread 'Alice in Wonderland' and pay more attention this time.
  21. 16  ^  more years of global warming
    The right way to do the graph would be (temperature-enso) vs (forcing). The graph Tom showed was temperature response vs temperature. The temperature-enso term is the second graph in the post linked from my #106. I'll try and produce the numbers, but either I have to revive some R code or do a lot more work on the browser version.
  22. 16  ^  more years of global warming
    I'm certainly interested. Detecting a 70 year cycle in a 130 year record is pretty much a fools errand, but for a 40 year cycle you might begin to have a chance (although you'd have to be supremely confident that you had correctly separated out the volcanic signal first). When Tamino argued against the AMO he got some serious scientists arguing for it. I'm afraid I don't know anything about it beyond that discussion though.
  23. Was 2012 the Hottest La Niña Year on Record?
    Apparantly from Dana and Composer99's comments above, Tisdale's nit pick is correct. I cannot help noticing, however, that 2007 lies above the trendline for La Nina years, and below the trend line for neutral years. Classifying it as a La Nina year, therefore, would increase the trend for both. (While we are nitpicking.)
  24. Was 2012 the Hottest La Niña Year on Record?
    Link in #16 is broken (the URL should be clipped following the "year/" part of the string, if that makes sense). With reference to Tisdale's claims, he might be onto something with regards to the nitpick about whether 2006 is a neutral year or not. The NOAA website states:
    DESCRIPTION: Warm (red) and cold (blue) episodes based on a threshold of +/- 0.5°C for the Oceanic Niño Index (ONI) [3 month running mean of ERSST.v3b SST anomalies in the Niño 3.4 region (5°N-5°S, 120°-170°W)], based on centered 30-year base periods updated every 5 years. For historical purposes cold and warm episodes (blue and red colored numbers) are defined when the threshold is met for a minimum of 5 consecutive over-lapping seasons.
    The OP here cites NOAA as defining a La Nina year as:
    NOAA defines a La Niña year as one in which the first 3 months meet the La Niña criteria that the Oceanic Niño Index (ONI) is less than -0.5.
    (This is a paraphrase of the State of the Climate report.) Of course, even if that is the case, it's spun all out of proportion to its importance relative to what is known/not known about global warming. Certainly it offers no support to Tisdale's unphysical pet notion that ENSO drives the apparent global warming. Bottom line: - It looks (to me, anyway) that Tisdale is correct in pointing out that, by NOAA's own standards, 2006 is a La Nina year and is warmer than 2012. - After that, Tisdale's got nothing, insofar as he is trying to take an apparent error in classification and transmogrify it into a refutation of conclusions based on physics.
  25. Was 2012 the Hottest La Niña Year on Record?
    renewable guy @16 - I think Tisdale is correct that Figure 1 in this post is based on an older version of the ONI which has now been superceeded, and that by their definition (first 3 months being La Niñas), 2006 should be the hottest La Niña year on record according to NOAA. Based on my methodology, 2006 is a Neutral year. However, 2009 was a slightly warmer La Niña year than 2012, as noted in the post above.
  26. 16  ^  more years of global warming
    I found "Atlantic Forcing of Persistent Drought in West Africa" by Shanahan, et al. in Science, 324, 2009. They did x-ray fluorescence of elements in lake sediments that they tie to temperature and drought, connecting the monsoon to the AMO. Anyway, going back 1000 years plus, it sure looks like they see something similar to our modern record in terms of these oscillations, but with a power spectrum that peaks at about 40 years, not 70. So, why should not I say....experimentally so far in my literature search the AMO is real? They also say there is a good correlation between their results and tree ring studies. I was expanding some of these plots on 500 year time scale with photoshop. I am going to systematically dig more of this stuff up. If there is an interst I will post some it.
  27. Philippe Chantreau at 04:42 AM on 25 January 2013
    Lessons From Past Predictions: Ridley vs. IPCC and Hansen
    Ridley is yet anbother one of those individuals whose ramblings deserve no attention whatsoever from the ones who can think, as shown above. It is really unfortunate that so many charlatans can gather so much attention these days. It seems to me there were times when the average ability of the population for critical thinking was much higher.
  28. Was 2012 the Hottest La Niña Year on Record?
    If I could have a little help on a topic that I think applies to this forum. I was given this link stating that 2006 should now be a la nina year and therefore 2012 is no longer the warmest la nina year on record. Link What constitutes a neutral year? 2006 starts with a la nina event and ends with a El Nino event. I suspect that Tisdale is being his PR WUWT self, I would just like to know the details of this.
    Moderator Response: [PW] Hot-linked reference.
  29. Lessons From Past Predictions: Ridley vs. IPCC and Hansen
    John Brookes @1 - yes, Ridley is one of those "lukewarmers" who's not in total denial, but also advocates for climate inaction because he doesn't believe AGW is a problem. From a practical standpoint for those trying to solve this problem, it's really not any better. Composer @2 and John Russell @3 - yes, a good scientist will admit when his prior conceptions were wrong. Ridley apparently will not (this is also a problem for some other contrarians like Richard Lindzen).
  30. Lessons From Past Predictions: Ridley vs. IPCC and Hansen
    Ridley is not sceptical, he's heels-in-the-mud entrenched. Completely unwilling to consider evidence, he clearly exhibits the ideological zeal of which he accuses others. Is he an example of psychological projection?
  31. Lessons From Past Predictions: Ridley vs. IPCC and Hansen
    I think the contrast between Hansen's re-assessment of his 1988 projections vs. Ridley's doubling down on his 1993 projections makes plain the difference between scientific and pseudo-scientific thinking. (If anyone cares to quote-mine the above, let me also note that the contrast makes plain that it is Ridley who is engaged in the pseudo-scientific thinking here.)
  32. Lessons From Past Predictions: Ridley vs. IPCC and Hansen
    At least Ridley predicts warming...
  33. 16  ^  more years of global warming
    Tom Curtis and Kevin, Does the the lowest graph in Tom's post 104 still contain the CO2 forcing? In my case I have subtracted the CO2 forcing for my graph in 102 above. It is not obvious to me that you would not get something similar to my graph in 102 if the lowest graph in 104 still contains the CO2 forcing, but that was removed using my method.
  34. 16  ^  more years of global warming
    Practical point here: Forgetting about whether my graphs in 101 and 102 are "publishable", clearly not...there is the practical question of how to best present the case for significant AGW to a hostile (mostly deniers) audience. I still like these long term plots of temperature versus log CO2 ratio. I show in 103 above that the 2 degrees C.S. is consistent with Foster and Rahmsdorf and others in the recent limit in which the first term in the expansion of the log is all you need. If I do the same log plot with Berkeley Earth I get 3 degrees C.S., not 2 which makes sense as Berkeley Earth is land based. (I recognize that these C.S. values are a form of transient response, and that once Arctic sea ice melting really strikes the C.S. will probably increase?) IMO, if you need to make the case that AGW is real and dangerous to an audience, the argument that "The climate simulations say it is happening and dangerous, therefore it is" is an argument that does not hack it, even to scientifically trained, but non climate trained, scientists and educators. This AMO thing......I am now bound and determined to go through the publications with a fine toothed comb...is there real evidence for a historical 70 year cycle or not, I mean going back before there was any AGW at all? If there is such evidence we can't just say there is no AMO and will have to deal.
  35. 16  ^  more years of global warming
    Tom: The natural-subtracted versions of the plot give a pretty good idea of the residuals... see here. The pure residuals will need me to implement csv output on that web app, it's on the to-do list, but very busy atm.
  36. 16  ^  more years of global warming
    Yes, but I am doing the CO2 forcing correctly, no, and the transient C.S. due to CO2 I get is reasonable. Somehow Zhou and Tung are getting a wildly wrong answer, with a CO2 C.S. about half what it really is?
  37. 16  ^  more years of global warming
    Curiousd @102, once again, total CO2 forcing is not the same as total anthropogenic forcing. Taking one recent assessment of the anthropogenic forcings since 1850, Skeie et al (2011), we see that total anthropogenic forcings were negative till about 1880, and zero from then till about 1900. After that they rose till about 1940, before falling back to zero around 1970, rapidly rising there after (red dashed line): That is quite different from the pattern exhibited by CO2 forcing over the same period (dark blue line): Note that Skeie et al do not show the close approximation between CO2 forcing and total anthropogenic forcing in the 21st century that is a feature of the IPCC AR4 and GISS forcing data. The aerosol forcing is uncertain, so it is unsurprising that this disagreement should exist. More importantly, the close approximation of the two values in the early twenty first century in those data sets that show it is a coincidence only, and does not apply throughout the nineteenth or twentieth century. It follows that what you show as a residual of the temperature record minus ENSO, solar, volcanic, and anthropogenic forcings actually contains a large component consisting of the time varying difference between CO2 and total anthropogenic forcing. If you use all forcings (in this case from GISS, and with GISTEMP as the temperature record), the residual will be much smaller, and without the apparent pattern shown in your residual: (Kevin C shows a picture of anthropogenic forcings used here. I would appreciate it if he were to show his actual residuals as well.) Obviously exact results will depend on which set of forcing data you consider more accurate and use.
  38. Putting an End to the Myth that Renewable Energy is too Expensive
    #60/61 winfield100: the analysis on reduced risk/impact of blackouts would apply to any form of distributed generation, e.g. small diesel generators. They would be able to provide a similar service even during night-time. Cheaper still would have been to clear the vegetation around the transmission line...
  39. 16  ^  more years of global warming
    O.K. see above graphs. Here is objection number one to Zhou and Tung. Foster/Rahmsdorf get 0.17 degrees C per decade. Lets check this with expectations. 1. C2/C1 = 2^ (temp/Tc.s.) 2. log base 2 (C2/C1) = temp/T c.s. 3. temp = T c.s. log base 2 (C2/C1)= T c.s. Ln (C2/C1)/ .693 [ .693 is natual log of 2] 4. Expand Ln (C2 / C1) around unity. Leading linear term is [(C2/C1)-1]. What is ( d/d time ) of [ (C2/C1) - 1 ] these days? maybe 2 ppm /year. Say {(384 - 280)/280} minus {(382 - 280)/280} ~ .3742 - .3643 = .007 . multiply by C.S. of 2, divide by .693 = .02 per year or 0.2 per decade. 5. Foster Rahmsdorf get about .17 degrees per decade, which is pretty close to what I get (0.20) for transient climate sensitivity of 2 degrees per doubling CO2 in the limit where we only need the first term in the expansion of the log around unity. By Zhou and Tung their AMO removal makes the increase per decade due to CO2 go down to less than half that which is the C.S. of CO2 alone no water vapor feedback!!!!! Spencer, et all are rejoicing!!! But if you do this right, as in my top graph, clearly everything fine with transient C.S. of about 2 degrees per doubling of CO2. Now go to second graph.....I think I recall there was recent work attributing the big 1940 peak partly to aerosols, somehow, but I also think I recall a phrase to the effect that they could not completely get all that peak this way. Then it is IMO most interesting that if you subtract expected CO2 , ENSO, solar, and volcanoes at the end of the day we are left with three peaks with about 70 year spacing? So maybe the "What's left over" does contain some AMO. And it looks like we are presently kind of near the top of a smaller such peak,and global temp increases are slowing, though clearly if analyzed correctly, the CO2 eventually takes over and we do have about the expected transient C.S.
  40. Carbon - the Huge and Yet Overlooked Fossil Fuel Subsidy
    To add to the comments of Ron @15: Considering externalities is useful but there are problems in calling them subsidies. Firstly, true subsidies are more likely to be susceptible to exact calculation, whereas externalities must necessarily be estimated. Secondly, the policy solution to each is very different. Subsidies can simply be withdrawn, while pricing externalities is more complex and requires institution of measurement and audit protocols for example. I'd also note that most estimates of subsidies in Australia for example incorporate tax expenditure that is a rebate on fuel excise already paid for certain qualifying uses of that fuel. So it's effectively a lower tax rate rather than a subsidy (this may or may not be a sound policy of course). Since 1 July 2012 the rebates have been lowered (i.e. tax rates raised) to include an estimate of the externality due to greenhouse gas emissions.
  41. 16  ^  more years of global warming
    Moderator Response: [DB] Fixed image.
  42. 16  ^  more years of global warming
    Moderator Response: [RH] Fixed image.
  43. 16  ^  more years of global warming
    Hi, I thought of the clearest way to state what I did here. 1. Start with data that has had ENSO,solar, volcanoes removed 2. Go all the way back to 1861, (where the linear approximation fails...note Zhao and Tung cannot go there!(their fig.4)) and plot log2( C/C1861) on horizontal axis, temp on vertical. Find good linear fit with transient C.S close to two. 3. Subtract the linear fit from data. Now we have data with volcanoes, solar, ENSO, and expected human caused AGW all removed. 4. Then you get,plotted against year what I call... Ta ta te ta te taaah "What's Left!" IMO the plot of "what's left" versus year is veerry interesting. Working on posting these.
  44. New textbook on climate science and climate denial
    In answer to comment #12 by calyptorhynchus, the second volume will be a tour through climates of the past and how our current global climate compares with past climates. There will also be coverage of health impacts on both animals and plants throughout Earth history. Volume 2 is in the planning stage and any and all suggestions are welcome. To comment #14 by jimvj, sorry about misspelling our great president's name. It's something neither the authors nor editors caught. The second edition will correct the spelling.
  45. New textbook on climate science and climate denial
    I used the "Look Inside" feature at Amazon to scan the Table of Contents; the first name of Barack Obama is misspelled as Barak Obama (22.6.4 section header).
  46. 16  ^  more years of global warming
    Tom Curtis - One problem I see in discussing the AMO is multiple definitions; ESRL's, Trenberth, etc. Each definition really requires its own analysis, something not clear when discussing the "AMO" without further qualifications. Kevin C - My expectations match your results. I'm looking forward to your updates.
  47. 16  ^  more years of global warming
    For what it's worth I've tried AMO and PDO. In both cases the statistics reject adding them to the model. In neither case does adding them change the conclusions. There will be an update in the next month or so including this and other FAQs.
  48. 16  ^  more years of global warming
    KR @95, land temperatures rise faster than sea surface temperatures under forcing. That means that GISTEMP will rise faster than SST under forcing solely on the basis that it includes large sections (30%) of land, meaning a chart of the North Atlantic SST anomaly minus Gistemp is not a useful indicator of anything much. Far more useful, and a far better definition of the AMO, is the North Atlantic SST anomaly minus the Global SST anomaly, as shown in the third panel of this graph:
  49. 16  ^  more years of global warming
    Fantastic video! May I ask how did you do your animations? I work with time series all the time and would love to have something like this for presentations. It was awesome!
  50. Subcap Methane Feedbacks. Part 4: Speculations
    "Once the Arctic carbon-cycle feedback boulder starts rolling down the mountainside, its course will be uncertain. Perhaps it will quickly come to rest again, or maybe it will trigger an avalanche that will wipe out the village below. This would be an entertaining and educational spectacle to watch from a safe vantage point on another planet, but the responsible thing for those of us who live here to do, of course, is to stop the fossil fuel emissions that are currently levering this boulder over the brink." Great final graph. Well-done!

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