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Friday round-up

Filed under: — group @ 24 July 2009

Two items of interest this week. First, there is an atrocious paper that has just been published in JGR by McLean, de Freitas and Carter that is doing the rounds of the denialosphere. These authors make the completely unsurprising point that that there is a correlation between ENSO indices and global mean temperature – something that has been well known for decades – and then go on to claim that that all trends are explained by this correlation as well. This is somewhat surprising since their method of analysis (which involves taking the first derivative of any changes) eliminates the influence of any trends in the correlation. Tamino has an excellent demonstration of the fatuity of the statements in their hyped press-release and Michael Tobis deconstructs the details. For reference, we showed last year that the long term trends are still basically the same after you account for ENSO. Nevermore let it be said that you can’t get any old rubbish published in a peer-reviewed journal!

Second (and much more interestingly) there is an open call for anyone interested to contribute to setting the agenda for Earth System Science for the next couple of decades at the Visioning Earth Science website of the International Council for Science (ICS). This is one of the umbrella organisations that runs a network of committees and programs that prioritise research directions and international programs and they are looking for ideas. Let them know what your priorities are.


533 Responses to “Friday round-up”

  1. 301
    t_p_hamilton says:

    David Watt wrote:”Having dealt with the 50 APS Society members who wrote to Nature, what is your take on the American Chemical Society who are threatening to throw out their editor for being too partisan in his support for AGW?
    Do you think there is any risk of the samr thing happening on Realclimate?”

    There is not even a risk of it occuring in the American Chemical Society. The letter writers all suffer from the Dunning-Kruger effect. It also demonstrates that there is not so much a problem with science education as with an attitude that truthiness (look it up) is better than becoming expert if you wish to argue against established science.

  2. 302
    Steve Fish says:

    Steve Reynolds #218. I checked out the Rank Exploits Blackboard link (same one I tried previously) and found your posts regarding censorship. You referred to a discussion on the Air Vent (tAV) as a worst case example entitled- “tAV to RealClimate, you can’t get there from here.” Several posters complained that posts on RC didn’t get through. These folks claimed that their posts were relatively simple and polite, and the discussion there was relatively low key so I have no reason to doubt them. On the other hand, some of their posts did get through and they, and examples of what didn’t, were so innocuous that I don’t see any reason to think RC would care, much less prevent them from appearing on their site.

    What the whole issue was about was the RC article by Eric Steig, “On Overfitting,” and the following posts there by RyanO regarding his amateure (I didn’t see any credentials) reanalysis of Eric’s data that he presented on tAV. This was also a polite discussion and Eric gave RyanO a lot of help, encouragement, and advice regarding his desire to publish his version of the analysis. Eric’s inline responses were as comprehensive as many research article reviewers comments I have seen, so the actual topic under discussion was not controversial and comments were not heated. One of the posters complained in an Overfitting post about not getting through and Eric said he didn’t know why. Would this happen if there was censorship?

    I have had one post to RC not make it and it was just a simple comment and question. I didn’t take this as censorship and just assumed that some of the glitchy behavior of the RC site (changes, spam filter, CAPTCHA) was responsible. When making a claim that information is being suppressed, one should consider what the information is and ask the question – to what aim? We all think that our own ideas are important and I suspect that some of the Air Vent guys were just hyperventilating a little. Steve Reynolds, like RyanO, post what you think is important and see what you get. Be persistent.

    Steve

  3. 303
    cugel says:

    steve reynolds #47 :

    Can you link us to any of these polite and reasonable comments that were rejected by RealClimate? Presumably these witnesses of yours, and you yourself, have posted some elsewhere as examples of the behaviour they complain of. There’s hardly be a copyright issue. So an example or two must surely be available. I’m sure we’d all appreciate a link or two. Otherwise we’ve only got your word about hearsay to go by.

  4. 304

    I thought I’d share an experience on my way to get people to conserve energy through green computing.

    So, my company makes green computers. Very low power consumption, really nice performance, not much more expensive than “other” computers, but definitely cheaper in the long run.

    Customer wants a system custom built — doesn’t like the price of a disk drive upgrade. I tell him “You’ll waste more power”. Then I tell him the dollar amount — more than what he was complaining about in the cost of the hardware.

    Real example — shows why we can’t seem to get anywhere on reducing consumption, because even when presented with the long term facts, it’s just easier to pay more later.

  5. 305
    Doug Bostrom says:

    cugel 30 July 2009 at 7:20 PM

    Why ruin a perfectly good tautology?

  6. 306
    sidd says:

    I just read a paper by Siddall et al in the latest Nature Geoscience, 26 July 2009. They derive a timescale for delay between temperature increase and forcing of approx. 3KYr fitted to data upto 22KY past. ANDRILL data indicate WAIS collapse in the order of 1KYr. Can we reconcile these estimates? Although admittedly the subject paper does not cover the ANDRILL timescales.

    Is it possible that either there is something like the Weertman instability absent in the last 22KY ? Or along the lines of the Hansen argument, Siddall et al. have modelled the timescale of the external forcing and not the internal timescale of icesheet collapse, especially given forcings as large as we see and project today ?

  7. 307
    Eli Rabett says:

    The governors of the ACS are NOT threatening to fire Baum, a few members are complaining about his calling a denialist a denialist, and others are backing him. Another example that you should RTFR. Of course you can find it at a link from this link

    Its the same with all the petitions, a couple of liars blow up the importance of a few outliers

  8. 308
    Layman Lurker says:

    #302 Steve Fish

    Steve, first of all I want to state outright that I have no problem with RC or how they conduct their moderation. If I try to post something and it doesn’t go through then so be it.

    You mentioned that some of the comments got through. If you are talking specifically of the “you can’t get there from here” thread I don’t think anyone got through (if I’m missing something point it out to me). Jon P posted a comment that I saw got through initially, but it later disappeared or was removed. I think most of us had links in our comments to the tAV thread which may have been the reason they did not get through, or in Jon’s case – removed.

  9. 309
    Alan C says:

    #270 Jim Prall
    This looks like a useful list, thank you. My first port of call when checking into authors that allege AGW is not happening has, thus far, been Sourcewatch.org. Bob Carter certainly has a reasonable entry there.

  10. 310
    Martin Vermeer says:

    Simon Abingdon #285:

    The 90% confidence in AGW has to coexist with a 10% chance of it being found to be false, otherwise the confidence in it would be greater.

    Once more, con amore (ma non troppo): the 90% is not a probability. The 10% is — but not the probability that AGW is false, but the probabiity that we would see warming in the specified range even if AGW were false.

    It’s about statistical testing. You cannot get there from here without grasping statistical testing first.

  11. 311

    Rod B writes, of extraterrestrials:

    Mark, pretty good (250). Except I think they’ll eat us, not enslave us; clearly not help us.

    The number of possible biochemicals is so astronomically huge, the chance that they could eat us is near zero. Most likely they will simply be unable to digest our flesh, but there’s also a good chance they’ll immediately go into anaphylactic shock.

    We can’t eat death cup toadstools, but those toadstools and ourselves evolved on the same planet within the last 2 billion years and use the same amino acids, nucleic acids, and genetic code.

  12. 312

    simon abingdon writes:

    Can you help my simple understanding by saying something useful about the “missing” 10% when a 90% confidence is claimed?

    If you have a measurement with a 90% level of confidence, say the absolute magnitude of a star at +4.84 with error bars of 0.24 magnitudes, you’re saying there’s a 90% chance the true value lies within 0.24 magnitudes of 4.84 (i.e., in the range 4.60-5.08), and a 10% chance it lies somewhere (anywhere) outside that.

  13. 313
    Martin Vermeer says:

    #306 Sidd:
    I read that article too. Please consider that they solve for tau (as a single constant, not necessarily very realistic) from a time span that covers both maximum land ice extent and the Holocene, and everything inbetween. IOW, on average a very different planet from the one on which the WAIS could collapse.

    Given also the relative crudeness of their model, I don’t see any cause for worry about the different time scales. But it is also true what you say (or imply), that the current forcing timescale is completely different from anything in the past.

  14. 314
    Hank Roberts says:

    wmanny, the question you asked in 296 is answered in my posting 293.
    As well as in many, many other places.

    Two-tail test, one-tail test, p .05 — apply to a particular set of data.
    fairly likely, good chance, pretty damn sure — apply to a whole area of study.

  15. 315
    Steve Fish says:

    Layman Lurker #308. I was referring to the Jeff Id post, #20, on the RC Overfitting thread.

    Steve

  16. 316
    simon abingdon says:

    Thank you Hank, Chris, Martin and Barton for your time and trouble.

  17. 317
    John Mashey says:

    re: #302, #308, #315

    Hyperventilating? :-)

    For those unfamiliar with tAV & Jeff Id, see <a href="http://noconsensus.wordpress.com/2009/06/05/data-or-politics/&quot;, which offers a clear viewpoint (* added to avoid spam filter):

    "No global warming again but that won’t stop the media onslought. The media won’t let the data slow them from continuing our march toward world-wide socia*list governance. You may find that statement extreme, in which case my opinion is – you aren’t paying attention."

  18. 318
    sidd says:

    Mr. Vermeer wrote:
    Re: Siddall paper
    “…solve for tau (as a single constant, not necessarily very realistic) from a time span that covers both maximum land ice extent and the Holocene, and everything inbetween.”

    To clarify, Table 2SI from the supplementary material, the fit tau to various subperiods of the data also.

  19. 319
    Gavin (no not that one) says:

    For the “90% confidence means there is 10% chance you are wrong” question, perhaps part of the problem is because the definition of a frequentist confidence interval does not admit statements such as “there is a 90% probability that the true value lies in the interval”, instead it means that “if you were to repeat the experiment a large number of times with independent samples of data then 90% of the confidence intervals obtained using that procedure would include the true value”. That isn’t quite the same thing, hence for a frequentist interpretation you can’t say there is a 10% chance the true value lies outside the interval, just that if you repeated the experiment a large number of times with independent data then 10% of the confidence intervals obtained would not contain the true value.

    I think that is why most people incorrectly interpret frequentist confidence intervals as if they were Bayesian credible intervals. ;o)

  20. 320
    Ray Ladbury says:

    In the case of the 90% CL cited by IPCC, I believe that the analysis is Bayesian–that is, it is subjective, but not arbitrary. I have pointed out several ways of demonstrating 90% confidence–e.g.
    1) looking at the sensitivity levels corresponding to high risk over the next century (e.g. 2 degrees or higher) and looking at the corresponding confidence level.
    2) looking at the number of GCM that can produce Earthlike behavior with low sensitivity (e.g. 0 out of 23)
    3) looking at the percentage of those publishing with some frequency in climate science who agree we are causing significant warming,
    4)and so on.

    Again, I would say that an assessment of 90% confidence

  21. 321
    Doug Bostrom says:

    It’s Friday again! How about some more roundup?

    As we know, firms dependent on the status quo of fossil-fuel dependency have a responsibility to resort to outright deception if no other means are available to “preserve shareholder value”.

    Here’s a nice little example of where industrialized deceit leads us:

    “Freshman Democratic congressman Tom Perriello — whose Virginia district leans Republican — faced a tough decision last month over whether to support the climate change bill. As he was weighing the issue, he got a letter from a non-profit group in his district that focuses on issues of importance to Hispanics. The letter urged Perriello to oppose the bill because it could raise low-income members’ utility bills. “Many of our members are on tight budgets and the sizes of their monthly utility bills are important expense items,” it read in part.

    But, reports the Charlottesville Daily Progress, the letter was a fake:

    “They stole our name. They stole our logo. They created a position title and made up the name of someone to fill it. They forged a letter and sent it to our congressman without our authorization,” said Tim Freilich, who sits on the executive committee of Creciendo Juntos, a nonprofit network that tackles issues related to Charlottesville’s Hispanic community. “It’s this type of activity that undermines Americans’ faith in democracy.”

    The faked letter from Creciendo Juntos was signed by “Marisse K. Acevado, Asst Member Coordinator,” an identity and position at Creciendo Juntos that do not exist.

    The letter — subsequently obtained by TPMmuckraker — had actually been sent by someone at the D.C. lobbying firm Bonner and Associates — a pioneer in “strategic grassroots/grasstops” lobbying whose clients have included Citicorp, Aetna, PhRMA, Dow Chemical, AT&T, and General Motors, among others.

    And Perriello staffers soon dug out five other forged letters — also obtained by TPMmuckraker — urging the congressman to oppose the bill — all purportedly from the local branch of the NAACP, whose president says he’s “appalled” at the scam.

    The paper adds:

    The fake NAACP letters were faxed to Perriello’s office from the Arlington headquarters of a company called Professional Risk Management Services Inc. A representative of the company said she had no knowledge of why the fax would have been sent from her office, adding that at least 60 employees have access to the fax machine.”

    I just love that glib mystification on the part of the PR firm.”No idea”. Hah!

    The rest of the story :

    http://tpmmuckraker.talkingpointsmemo.com/2009/07/lobby_firm_sent_forged_climate_change_letter_to_c.php

  22. 322
    Steve Reynolds says:

    302Steve Fish: “… post what you think is important and see what you get. Be persistent.”

    Thanks for the encouragement and for having enough of an open mind attitude to look into this. I hope you will follow the continuing discussion that is occurring, including a response at tAV (which I see is already being attacked here for irrelevant reasons).

  23. 323
    Mark says:

    It is also “at least 90% confidence”.

    Strange how that’s forgotten all the time.

  24. 324
    Rod B says:

    wmanny, et al, actually it was Stan Freberg, not Tinothy L. who wrote and sung a comic ditty about Fug Soap (“…if your regular soap won’t clean your pots,….)

  25. 325
    David B. Benson says:

    The internet is “best effort” but there are no guarantees. Sometimes comments are simply eaten by The Internet Monster for no obvious reason.

    Do not assume intentional censorship.

  26. 326
    Rod B says:

    Barton (311), Whew! Thanks! That’s a relief! :-)

  27. 327
    Doug Bostrom says:

    By the way, in connection with the apparent systematic fraud being committed by PR firms as noted in post 321, RC sure did see a big wave of concern for the poor being trotted out a few weeks ago by the usual suspects, just prior to the Waxman-Markey vote.

    Strictly coincidental, I’m -sure-. Doubtless this wave of benevolent feelings was entirely spontaneous, not engendered by any gullible uptake of industrially synthesized talking points.

  28. 328
    Steve Reynolds says:

    325David B. Benson: “The internet is “best effort” but there are no guarantees. Sometimes comments are simply eaten by The Internet Monster for no obvious reason.”

    In this case one comment was actually posted, then deleted (see 308Layman Lurker).

  29. 329
    Jim Galasyn says:

    Old news, but the SciAm comments could use some help:

    Stumbling Over Data: Mistakes Fuel Climate-Warming Skeptics
    Do minor errors erode public support on climate issues?
    By David Appell

    Even as the Obama administration moves ahead with modest plans to tackle global warming, the public relations battle on the issue is as fierce as ever. Some recent scientific stumbles haven’t helped. In fact, they have given fodder to climate change skeptics, some of whom have seized on the errors to attack the credibility of scientists and sway public opinion.

    Many scientific organizations, such as the NASA Goddard Institute for Space Studies, now put data (some near real-time) on their Web sites. The information ranges from raw numbers from weather stations to computed values of, for instance, monthly global temperature anomalies, which represent temperature deviations from a historical average. Typically researchers make corrections and adjustments as they check equipment and replicate experiments.

    In today’s politically charged environment, though, these routine corrections have become ammunition in the warming war. For example, last November Internet users found that raw data erroneously replicated from Russian weather stations contributed to a suspiciously high temperature anomaly that Goddard published. Two years ago the blog Climate Audit, run by amateur scientists and self-described “science auditor” Steve McIntyre, found that an error in a computer algorithm had ranked 1998 as the warmest U.S. year, instead of the correct 1934. (The change did not significantly affect global values: 1998 was still the earth’s warmest year as ranked by satellites, although Goddard has 2005 as slightly warmer.)

    But perhaps the mistake that got the most publicity for skeptics happened in February as an automated system of the U.S. National Snow and Ice Data Center (NSIDC) published information on the extent of Arctic sea ice. It contained a small but strange hitch indicating that enough ice to cover California was suddenly gone. Internet readers pounced, sending e-mails to the center and also to skeptical bloggers such as meteorologist Anthony Watts. His blog, Watt’s Up with That?, is read daily by about 21,000 people around the world (according to Quantcast, which compiles Web site statistics), and Watts’s post about the error mushroomed across the Web. Within hours the NSIDC withdrew the data, ultimately finding that the glitch resulted from a faulty sensor on a satellite. The NSIDC scientists admitted the mistake, corrected the problem using a different sensor and audited all past data.

    But the public-relations damage was done. …

  30. 330
    Jim Galasyn says:

    Do we have a convenient source for refuting contrarian claims that “Hansen didn’t release data/source code for X years”? I see that accusation all the time.

  31. 331
    John Mashey says:

    re: #327 Doug

    re: “the poor”
    This is just another instance of Lomborg-style misdirection arguments.

    I.e., political advocates normally unknown for helping X claim that Y must not be done lest it hurt X, with the idea of confusing those who actually sometimes do care about helping X.

  32. 332
    catman306 says:

    If the US medical industry is spending the reported $1.5 million every day to prevent health care reform, how much are the fossil fuel interests spending every day to prevent real information about AGW from entering the consciousness of the American public? How long have they been at this? Would they or their agents do anything illegal or unethical to accomplish this goal of ignorance for America, of maintaining the energy status quo in the US?

  33. 333
    David B. Benson says:

    catman306 (332) — Seems that has already happened; see
    http://initforthegold.blogspot.com/2009/07/john-kerry-fraudulent-letters-advocate.html

  34. 334
    Steve Reynolds says:

    303cugel: “Can you link us to any of these polite and reasonable comments that were rejected by RealClimate?”

    I submitted a comment with links at 31 July 2009 at 1:18 PM.

    [Response: A ‘polite and reasonable’ link to a impolite and unreasonable site is not ‘polite and reasonable’. This is a moderated forum for people to discuss substantive issues, not a platform for people to martyr themselves about how unfair we are. Play those kinds of games somewhere else. – gavin]

  35. 335
    David Horton says:

    This http://www.media.rice.edu/media/NewsBot.asp?MODE=VIEW&ID=12794&SnID=2075327496, a summary of a paper by Gerald Dickens, Richard Zeebe of the University of Hawaii and James Zachos, has now bounced into the denialosphere on the heels of McClean et al. It could do with some discussion here perhaps. “Gerald Dickens, a co-author of the study and professor of Earth science at Rice University. “There appears to be something fundamentally wrong with the way temperature and carbon are linked in climate models.”” “Dickens said, is that something other than carbon dioxide caused much of the heating during the PETM”. It seems to me, on a preliminary read, that they are confusing CO2 and total greenhouse activity in the PETM, but that seems to obvious. Anyone?

  36. 336
    Jacob Mack says:

    Okay folks,
    most of the major companies are now admitting in commercials and in their research that AGW is a real and serious issue; not all,but many. Solar voltaic cells are getting more sophisticated (smaller) and less expensive to produce, while more wind mills are being placed, and the smart grid is coming closer to reality. Still, there is no economically feasible way to just end coal burning anytime soon or have everyone use solar panels either. How are we going to generated that much electricity? Look at this months Scientific American where Yucca is discussed to see the detriments of nuclear power plants becoming the dominate energy source in the US. Yes, France and Japan are handling it well, but the fallout from a leakage from just one nuclear power plant is enormous… The argument may be made that nuclear storage facilities can many decades storing spent fuel without any great issues, but as it satnds now 131 locations in the US are storing what was being stored at Yucca…also there is not forseeable “tipping point,” from a 2,3,4,5, degree increase in global mean temp, so we do have time to think this through and engineer ways to reduce GHG emisssions; nuclear is not the answer,even though we do need to reduce coal burning. There is cleaner burning coal, this is a scientific fact now, not conjecture or politics. Carbon sequestering looks good, S04 injections is idiotic, and that underground storage frightens me as well…same level of risk, if not greater than allowing the planet to continue warming up. Then agaion we have a nice pause in warming now, so now is the time window to create new and improved ways to reduce GHG emissions… we are not going to be underwater just yet, so hopefully we can think through better ways than what we have at hand.

  37. 337
    simon abingdon says:

    Ray #193 “We are told that an opaque jar contains both black and white balls”, later “we have no evidence that there are ANY white balls in the jar at all” Thus are we lured into enforced cognitive dissonance so that Ray can expound his argument. Now after several expert opinions have been expressed (not all mutually consistent) Ray now says (#320) “In the case of the 90% CL cited by IPCC, I believe that the analysis is Bayesian–that is, it is subjective, but not arbitrary”.
    What store should we set by Ray’s beliefs I wonder. (There are people who believe in the Ascension).

  38. 338
    Martin Vermeer says:

    #330 Jim Galasyn,

    what about, instead of refuting, making the counter-claim “those data and code have been out on the Intertubes for X years now, and how many contrarians are actually using them for study?”

    I mean, those goal posts are designed for mobility ;-)

  39. 339
    Martin Vermeer says:

    > In this case one comment was actually posted, then deleted

    Yes, I have experience with this too: I pointed out an obviously libelous comment to the moderators, and it (and mine, left dangling) disappeared. Censorship? No, editorial oversight based on law.

    This moderation is volunteer work. Don’t shoot the piano player.

  40. 340
    Chris Dudley says:

    Doug (#321),

    A very interesting story indeed. What will be quite interesting will be to find out how many other members of congress have been contacted in that fraudulent manner. Reminds me very much of Dartmouth Review tactics. Wonder if there is a connection.

  41. 341
    Mark says:

    “Now after several expert opinions have been expressed (not all mutually consistent)”

    Because you are not mutually consistent in what you ask to be explained.

  42. 342
    Hank Roberts says:

    For David Horton, Hrynshyn has pretty well nailed down the denial nonsense based on the Zeebe/Dickens/whoever paper, here; click the links he gives:
    http://scienceblogs.com/islandofdoubt/2009/07/gaps_in_climate_knowledge_oh_n.php

  43. 343
    Steve Reynolds says:

    338Martin Vermeer: “I pointed out an obviously libelous comment to the moderators, and it (and mine, left dangling) disappeared. Censorship? No, editorial oversight based on law.”

    Yes, I once pointed out a similar comment, with the same result. That kind of ‘editorial oversight’ is fine.

    However, in this case a posted comment about an independent analysis of Antartic [edit – trolls gets moderated out. There are other sites that thrive on ad hom, bad faith, unfounded claims, charges of fraud, dishonesty, etc. Take it over there, but don’t complain if we’re not buying it here. This thread is over now. Come back when you have something constructive to contribute.]

  44. 344
    Martin Vermeer says:

    #252 Simon Abingdon:

    Martin #246 I’ll try again. Ray #193 says “90% confidence does not equate to a 10% chance of being wrong”. Therefore 90% confidence does not equate to a 90% chance of being right.

    Indeed not.

    What then is the relationship (if any) between probability and confidence expressed as a percentage (not confidence interval or confidence limit, just plain “confidence”)?

    OK, you asked for it :-)

    It’s about the difference between forward inference and reverse inference.

    Forward inference is if you have a model or hypothesis — like, a general circulation model allowing you to compute radiative forcings for anthropogenic changes in atmospheric composition. Given this model, you can compute probabilities for certain observational outcomes — like, we see the forcing from 1750 to today to be in the range 0.6-1.6 W/m2. Or outside that range. “Confidence” refers to these probabilities.

    Now what you and everybody is asking about, is “what is the probability that this model is right, given these observations?” That is reverse inference. It is generally impossible to do unless you have a priori information on how likely your model is to be true, according to a famous theorem by the good Reverend Thomas Bayes in 1764.

    There are many murky expositions about Bayesian statistics on the Web; I like the not-so-murky one by tamino. Seee also Yudkowski.

    To repeat, am I wrong to equate confidence with probability by saying (for example) that my confidence is 50% that the next coin toss will come down heads?

    Scientifically, yes, that’s wrong. It’s not a hypothesis, it’s a forward inference. The hypothesis (unspoken) could be “the coin is fair”.

  45. 345
    Doug Bostrom says:

    Chris Dudley August 2009 at 2:36 AM

    I suspect that an ambitious prosecutor could construct an indictment around that incident, with several counts. I’m not getting my hopes up; for some reason these sort of dirty tricks seem to be considered acceptable, rarely result in a prosecution.

    Looking back on the general tone of the political discussion around Waxman-Markey I think it’s fairly reasonable to conclude that these letters were part of a pretty large, coordinated effort. It sure would be fascinating to see concerted investigation applied via subpoena to follow the money home! A different kind of science, hmm?

    Another thing that immediately springs to mind: just how “spontaneous” are letters such as that sent to Nature? Wouldn’t it be interesting to know the exact manner of their inception? I’m not suggesting for a moment that most or even many of the signatories are bad people as opposed to careless. Rather, I just wonder who provided the impetus to get the ball rolling?

    One huge problem with this industrialized deceit is that it’s very corrosive to trust.

  46. 346
    simon abingdon says:

    Martin #344 Thank you for pointing me in this direction. I now understand that the application of Bayes’s theorem to calculate posterior probabilities depends on a knowledge of the prior and conditional probabilities in question. Can you set all this in the context of GCMs and AGW theory for me? For example how does the level of confidence in the prior and conditional probabilities affect the confidence level of the posterior probability? (If I’m using too much of your time just say “look it up for youself”). Many thanks for listening.

  47. 347
    John Mashey says:

    re: #345 Doug
    Letters to APS & Nature.

    I’ve been studying the network effects and underlying reasons for anti-science for a while, and this is just another case. I hope to have finished doing a decent writeup of this one in a few more days.

    I’d estimate that the chances of the Nature & APS letters being spontaneous are ~0:

    S. Fred Singer1, Hal Lewis2, Will Happer3, Larry Gould4, Roger Cohen5 & Robert H. Austin6

    are all well-known to those who study anti-science in climate.

    The first APS letter had 54 signers, including all of the above. They obviously got there by personal contact of one sort or another, of which many of the relationships are pretty obvious.

    The July 22 list added 8 (Brown, Drallos, Gamblin, Hameed, Judd, LeLevier, Oehler, Sundelin), and dropped Lewis, which I think is accidental, so I count 62 altogether.

    The list of 62 includes ~25% hardcore AGW anti-science folks, some obvious friends and colleagues,some for which plausible connections exist, but aren’t yet solid to me, a few where I don’t see the connection, and one or two who *really* surprise me by being on the list. About 30% are Retired/Emeritus.
    More later, must go.

    BUT: hints
    Nuclear Physics
    Cold-war
    George C. Marshall Institute
    Los Alamos National Lab (and to lesser extent) Livermore National Lab, DOE
    Princeton
    U of Rochester
    Connecticut schools and New England APS
    APS FPS

    See:
    Naomi Oreskes’ lectures, The American Denial of Global Warming in illustrating how some very senior scientists became dedicated anti-science advocates in starting the George C. Marshall Institute. The interested reader should anticipate her forthcoming book, which goes into much more detail.

    Myanna Lahsen, Experiences of modernity in the greenhouse: A cultural analysis of a physicist “trio” supporting the backlash against global warming (2007)” may be the single most relevant reference. Many of the signers seem members of social network involving nuclear (and related) physicists, often of cold-war experience, and Lahsen offers rationales for such behavior.

  48. 348
    Mark says:

    abingdon, let me ask you a question:

    Is Iliad’s “the fall of Troy” right or wrong?.

    If you say “wrong” because it’s all about gods and sirenes and magic and stuff that isn’t possibly true, then I counter with: there IS such a place as Troy, Greece and Meneleus looks likely to have lived etc.

    If you say “right” because there are elements in there of things that really happened, then I’ll point our Cierce.

    The thing is that the entire work is not a single thing. There are many things contained therein.

    Yet you want to put right/wrong on the IPCC report as if it were a single thing.

    And this is just as wrong as asking “Is Iliad’s Fall of Troy factual or fiction?”.

    Until you toss that next coin, the chance of a head or tail remains a mathematical construct.

    It remains uncertain.

    And not 50-50. The coin could fall skew. Could be stolen. Could fall between the floorboards. It could even balance on the edge. All of which are not head or tail.

    But once you’ve tossed the coin, there is no confidence: there’s only the fact of which way the coin landed.

  49. 349
    Martin Vermeer says:

    Re #346 Simon A.

    Just some references. James Annan’s empty blog (sidebar) has some good old discussions on this subject. I also wrote myself on it while I was learning it, see here towards the end.

    Example: if you write Bayes as

    p(P|Q) = (p(Q|P)/p(Q)) p(P), where

    P is the stochastic variable describing the model:
    P = 1: the greenhouse effect is real and about as strong as we think it is,
    P = 0: it isn’t.
    Q is the stochastic variable describing the observation:
    Q = 1: we’re seeing around 0.7C warming since pre-industrial
    Q = 0: we don’t.

    Now look at the two panels of Figure 9.5 in the latest IPCC.
    They give us p(Q|P=0) and p(Q|P=1), respectively; close to zero and close to one, as you see. p(P) represents our belief in the validity of the theory: I would put something like p(P=1) =0.99…, a skeptic considerably lower :-)

    Don’t worry too much about p(Q), it’s just for scaling. Now we can compute p(P=1|Q), the probability that the model is valid given the observations (and of course for this prior).

    Hope this helps a bit (and is correct). It took me a while…

  50. 350
    Ray Ladbury says:

    Simon Abingdon asks: “What store should we set by Ray’s beliefs I wonder. (There are people who believe in the Ascension).”

    For the record, I do not believe in the Ascension, virgin birth, Santa Claus, the Easter Bunny, and a host of other things. I do believe that it is possible to construct a reasonable and rigorous Bayesian analysis that reasonable people will find cogent. I have outlined a few manners by which one could attempt such wrt the level of confidence in climate science.

    Simon, have you read the analysis by Annan and Hargreaves about the influence of priors on the determination of climate sensitivity? They’re pretty good examples of doing things the right way:

    http://www.jamstec.go.jp/frcgc/research/d5/jdannan/believe_grl.pdf


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