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Humlum is at it again

Posted on 23 May 2011 by julienx2k2

In their opinion article in the widely-read Norwegian newspaper Teknisk Ukeblad  (translation available here) which followed an initial letter in the same newspaper, Dr. Bye, Prof. Humlum, and Dr. Stordahl (BHS), attempt to refute what they call the “CO2 hypothesis” (usually called in the literature Anthropogenic Global Warming, or AGW theory – it is a theory). Their argument is articulated as follows: firstly, they dismiss categorically that a methodology exists which would allow for attributing the current observed global warming to human activities with a confidence of at least 90%.  BHS pretend that the IPCC assigns confidence levels to scientific positions based on the outcome of a simple vote.  They suggest that the more votes a statement (e.g., “global warming is mostly due to human activities”) receives, the higher confidence the IPCC assigns to it. As discussed below, this is by no means how the IPCC determines confidence levels.  BHS are criticizing the IPCC for something it does not actually do.

Having seemingly wiped out the entire AGW hypothesis theory by this ingenious but incorrect argument, BHS then take on the challenge to propose an alternative explanation for the increase in the mean global temperatures observed since the beginning of the Industrial Revolution –an increase that they do indeed accept as real and scientifically valid.  BHS suggest the warming is simply due to natural factors. To support their hypothesis, they rely on a simple figure (incidentally also present on the website of one the authors) showing the evolution of the atmospheric CO2 concentration as well as the simultaneous temperature record taken from the GISP2.  Skeptical Science readers may recall this figure from Rob Honeycutt's Crux of a Core 3 (Figure 1).

Figure 1: GISP2 temperature data and EPICA Dome C CO2 data from Climate4you.com

Proud of their achievement, BHS end the correspondence by reminding the reader that they are strong defenders of the true and pure scientific methodology.

Unfortunately for BHS, we feel obliged to notify them that nothing in their communications comes close to such an ideal, unbiased, and intellectually honest scientific approach. This post aims at providing with some clarifications that have been regrettably omitted from the BHS correspondence, and that we feel are essential for the interested reader to take an informed position on the issue of AGW.

Their whole critique is directed towards the attribution of climate change: basically, is it mostly natural (the BHS hypothesis) or mostly anthropogenic (the AGW hypothesis theory)? The Working Group I of the IPCC has dedicated Chapter 9 to this question in its latest assessment report (AR4WG1), to which we refer in the following. We also provide throughout this post links to peer-reviewed scientific papers, or to web pages linking to such publications, because we believe that any claim must be substantiated by relevant and solid supporting evidence.

About the likelihood of AGW

Let us start with the definition of the likelihood [1]. BHS base their work on a single quote coming from a single scientist, Prof. Eystein Jansen.  This is not scientifically rigorous, especially when the quote is taken from a TV show that by nature does not allow for complexity to be discussed in details and where approximations are often tempting to make for the sake of brevity.  BHS should know that scientific methods have never been defined on air but in the peer-reviewed literature.

The IPCC works with likelihoods, summarized in Table 9.4 of Chp. 9. Likelihood “refers to a probabilistic assessment of some well defined outcome having occurred or occurring in the future” [2].

The likelihood for the observed surface warming of the Earth in the last 50 years is very likely (>90%) not to be due to natural causes alone, and very likely (>90%) to be dominantly caused by greenhouse gas forcing [3]. In other words, taking into account all the known factors contributing to defining the behavior of the climate system, and in particular the human-caused emissions of greenhouse gases, the probability of obtaining the current surface temperature (including increased ocean temperatures) is more than 90%.

The method followed to derive these probabilities that define likelihood “may be based on quantitative analysis or an elicitation of expert views” [2]. In addition, whatever the outcome of the estimation process, sources of uncertainty must be mentioned and discussed. The treatment of uncertainties by the IPCC is discussed in Section 1.6 of AR4WG1, and has been the subject of a recent meeting of the panel experts.

So no, the 90% likelihood that global warming is due to human activities is not the result of a poll among climate scientists, but stems from complex statistical methods and is based on many lines of evidence, some of which are introduced below.  The fact that 97% of practicing climate scientists support the theory of AGW is actually a consequence of this extremely strong likelihood, rather than a cause, as BHS want us to believe.

BHS will rightly point out that the likelihood determination, following the IPCC guidelines, also can be done following an “elicitation of expert views”, when purely statistical methods cannot provide with a satisfying estimation. So let us review some facts BHS have forgotten but that experts know about.

Anthropogenic Warming Fingerprints

A critical step in determining the likelihood of the warming to be anthropogenic is to gather information about the phenomena.  The more data is gathered the better it is, especially if they come from distant scientific fields, because the test a given hypothesis is submitted to becomes harder to pass.  This way a hypothesis can be falsified.

There are many observations that support the theory that the recorded mean surface temperature increase is mainly caused by anthropogenic greenhouse gas emissions: less heat escaping to space, more heat radiated back to the surface at the CO2 absorption wavelengths, cooling upper atmosphere, heightened boundary between the lower and upper atmosphere, more warming during nights than days, etc.

In the meantime, the likelihood for natural factors alone to explain the increasing global temperatures and these observations is less than 10% (FAQ 9.2 of AR4WG1).

Instead of mentioning the larger temperature increases over land than oceans, which can be due to other causes than increased GHG concentrations as they rightly point out, we suggest that BHS start by scientifically refuting the above-mentioned CO2 fingerprints.  Because that would precisely falsify the CO2 hypothesis AGW theory they want so much to tear down, and perhaps the likelihood of their hypothesis would rise above 10%.  In doing so, BHS would follow the scientific method they are proud proponents of, and all awkward jumps to the conclusion that “it’s not us” will be avoided.

Cherry-picking and inventing data

A particular point BHS touch upon is the “hypothesis” that increased CO2 concentrations leads to increased water vapor content in the atmosphere.  This “hypothesis” is thermodynamically founded.  Warmer air can hold more water vapor in absolute amounts, so any factor leading to increased atmosphere temperatures ultimately leads to higher water vapor contents.  And a human-caused increased atmospheric concentration of greenhouse gases (also called heat-trapping gases) is no exception to the rules of thermodynamics, despite what BHS pretend.

Increased water vapor content and its corresponding radiative forcing have indeed been both recorded (see here for numerous references).  Dessler et al. (2008) even write that "the water-vapor feedback implied by these observations is strongly positive, with an average magnitude... similar to that simulated by climate models". The same that BHS dismiss as incapable of dealing with this issue.

Our last comment concerns their way of demonstrating how increased GHG concentrations cannot explain the recorded temperature increase. BHS rely on the GISP2 database to draw their graph. Unfortunately, GISP2 is concerned with local temperatures which do not accurately represent the average global temperature – nor even the Northern Hemisphere.  Drawing conclusions on the global climate based on GISP2 amounts to pretending that the whole world is affected by heavy rainfalls based on the precipitations in Bergen [a Norwegian city known for plentifull rainfall].

More disturbing is that as mentioned above, this critique and a rebuttal of their graph had been published by Skeptical Science some weeks before the second publication of BHS, and Prof. Humlum was contacted and stated that he would update the erroneous figure.  His way of “correcting” his mistakes does not qualify for very scientific, as is detailed in our reference.  Worse than that, comparing the simultaneous temperature and CO2 concentration is extremely misleading, as every concerned person knows that the climatic system has a large inertia.  This means that the full effects of the explosion of the CO2 atmospheric content we are causing will be seen in several decades only – but then again the GISP2 data won’t be representative of the global situation.

The observation by BHS that the mean global temperatures have dropped during the Holocene while the CO2 concentration should have led to an increase has been discussed in another post of Rob Honeycutt, and has well-known natural causes. It is wrong to infer that the current anthropogenic CO2 increase (+115 ppm from pre-industrial levels, and counting) has no effect on global warming because a 20 ppm increase in the Holocene took place as the temperature dropped slightly. The AGW theory does not pretend that natural factors cannot affect the global climate.

Conclusion

We have been very critical of the correspondence of BHS.  Some might even say harsh.  But we must acknowledge that their contributions are very interesting.  In fact, their letters provide with a perfect example of the strategies deployed by climate "skeptics" to twist the debate and sow doubt in the minds of the public.  BHS articulate their argumentation around the defense of an ideal of scientific method they believe in while clearly violating the rules they pretend to respect.  Citing irrelevant quotes or taken out of their context, misunderstanding fundamental concepts, concentrating on precise points without looking at the broad picture, cherry-picking or even inventing scientific facts and data in order to provide with justifications to their hypotheses, etc.

So we would like to thank them from the heart, because they have chosen to be good examples of how science should not be done, how climate science can be at worst when left to the sole hands of so-called climate "skeptics".

Notes and references:

[1] An issue with Norwegian is that there exists only one word for the two technically different concepts of probability and likelihood. The inputs to a problem define the probability of an outcome (if my dice is perfectly balanced there is an equal probability of obtaining each number from 1 to 6), whereas the likelihood of the outcome is determined as a function of the inputs (if I obtain more 6s than other numbers after a large amount of tests, the likelihood of the dice being loaded is high). Incidentally, the likelihood of an event to be due to a given factor is defined as the probability of its occurrence given the factor.

[2] Guidance Notes for Lead Authors of the IPCC Fourth Assessment Report on Addressing Uncertainties, 2004, available here. See as well IPCC Expert Meeting on Detection and Attribution Related to Anthropogenic Climate Change, 2009, available from the same website.

[3] Interestingly, the IPCC aggregates into surface warming the increasing ocean temperatures. Looking at this broader scale than merely surface atmospheric temperatures actually follows a stringent scientific approach: ignoring the increase of the ocean would amount to estimating the size of an iceberg solely by looking at its emerged tip. The informed reader will notice that so-called climate skeptics very seldom mention the ocean in their quest against the AGW theory, since doing so would severely impact their conclusions.

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Comments

Comments 1 to 32:

  1. Let's agree to disagree about OHC. You can cite papers showing it is rising, I can cite papers showing it is cooling.

    When looking at a lot of literature, the error bars overlap enough that about all that can be concluded is that the OHC is flat with a negative bias.
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    Response:

    [DB] OK, what published, peer-reviewed papers do you have?  Links to sources (not blogs) please, to be taken seriously.

  2. Papers can't change reality, Camburn. Although OHC in the upper 700 meters has leveled off over the past few years, the upward long-term trend is clear. Especially if you look at all the data, which the 'papers' to which you refer (probably Douglass and Knox) do not.

    Regardless, if you want to argue this subject, please take it to oceans are cooling.
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  3. @Camburn:
    Agree to disagree? This is a matter of data, not agreement, or theory. With a little house cleaning to toss away "some parts of some oceans are cooling sometimes" nonsense, papers on opposite sides of "the oceans are warming" question can be resolved, as a matter of fact.


    If the ocean is warming, and a citation says it is not, then the citation is flawed. Citing a flawed study does not change fact.
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  4. (Argh. The Faux-News-ification of knowledge)
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  5. dana1981:
    You are correct that the upper 700 meters has leveled off and a linear trend, even with the leveling off of temp, is correct.

    As far as 2,000 meters, the results have been models, not measurements to date. There are current measurements being taken, but the reliability of said data is so short that nothing of consequence can be derived from that data.

    Sorry paul@4:
    I don't get Fox news, as I can see no value in cable so don't subscribe. I read literature instead, is much more reliable and interesting.
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    Response:

    [dana1981] Incorrect - von Schuckmann (2009) is based on ARGO data, and Purkey and Johnson (2010) use data from ship-based Conductivity-Temperature-Depth (CTD) instruments, for example.  Please don't just make stuff up, Camburn.  I lose patience with people who make false unsubstantiated claims very quickly.

  6. So come on Camburn, you've been asked to back your claim of having papers showing a cooling in OHC, yet you still haven't provided it. Until then, I don't think we can take any claims by you seriously.
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  7. Dana1981:
    The Schuckmann paper threw out some ARGO data, and if memory serves me, used a combination of xbt and ARGO. The xbt data is so prone to error that for specifics it is not very reliable.

    I have not read Purkey and Johnson, but will have to do so. Thank you.
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    Response:

    [dana1981] regardless of what you think of XBT data, it is data.  I accept your withdrawal of your previous comment.

  8. Dana,

    Camburn seems to wandering off topic again and arguing strawmen. OHC is not relevant/critical to this story as far as I can tell. But is he claims to be so interested might I suggest that he add von Shuckmann and Le Traon (2011) to his list of reading.

    Now back to the topic at hand please?
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    Response:

    [dana1981] Agreed, as I suggested in #2, further discussion of OHC should go in 'oceans are cooling'.

  9. Thanks for the article, julienx2k2. As you state, a classic example of why what the 'skeptics' are doing is not science.

    It would interesting to see if a rebuttal argument, demonstrating why the BHS opinion piece was incorrect, was able to be published in the same newspaper, or whether editorial policy only provides 'balance' when it suits their agenda (as seems to be the case in many media outlets around the world).

    Re the 8 off-topic comments above: I, too, struggled to make any connection between the article and a discussion of OHC. Camburn's first comment strikes me as a typical denier misdirection away from the demonstrated flaws in the anti-AGW case ("Look over here at this super-strong floodgate, don't pay any attention to the torrent pouring out of that crack in the dam over there"). The SkS comments policy clearly states that off-topic comments are not permitted. Perhaps a slightly firmer moderation policy needs to be enforced, with such posts deleted? It might reduce the thread hijacking that goes on sometimes.
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  10. Bern:
    My comments on OHC were derived from what was written in the post:
    "The informed reader will notice that so-called climate skeptics very seldom mention the ocean in their quest against the AGW theory, since doing so would severely impact their conclusions."

    I still stand that OHC of 0-700 meters is flat to negative.

    I have not read parker yet, so I will not comment on his paper.
    Schuckman has problems in his paper. I had read it earlier, and will do so again. However, I will not discuss it on this thread as it is considered off topic.
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  11. Camburn @7: Your memory fails you:

    "The basic materials for this study are the monthly gridded fi elds of temperature and salinity properties of the upper 2000m over the period 2003-2008. These fi elds were obtained by optimal analysis of the large in-situ data set provided by the Argo array of profi ling oats (www.argo.net). Complementary measurements from drifting buoys,CTDs and moorings are also used. Two important data sets have been excluded from the analysis because of proven or suspected biases. They are fi rst, the XBTs and XCTDs for which uncertainties in the accuracy of the fall rate remain, and second, a small subset of Argo float profi les of type SOLO (Sounding Oceanographic Lagrangian Observer) that suff er a labelling error in the pressure [Willis et al., 2007]. The data set was downloaded
    from the Coriolis data center (one of Argo Global Data Acquisition Center, GDAC) at three dates: the period 2003-2006 was extracted in August 2007, the year 2007 in January
    2008 and the year 2008 in February 2009. In total, the Argo measurements account for at least 90% in 2003 and increase to more than 95% since 2006."


    As you can see, all XBT and XCTD profiles where excluded because of uncertainties related to the pressure at each data point. ARGO profiles for which there was similar uncertainty were also excluded. I am sure that, being consistent, you would want all the XBT profiles included if and only if you were to include ARGO profiles of uncertain pressure readings are also excluded. Or do you just want to cherry pick?
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  12. Camburn @10, the appropriate conclusion when you claim that Schukmann has problems in her paper but do not link to a discussion of those problems is that this is just hand waving, and you are rejecting the paper solely based on your dislike of the conclusions.
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  13. Tom@11:
    The discussion is on a link provided by Dana 1981.

    No, it is not the dislike of the conclusion.
    It is the probability the conclusions are correct that is in question.

    I refer you to the link.
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  14. Tom:
    I have to let others who are immenently qualified speak clearer than I can I guess:

    I do think that Pielke Sr, Dr. Trenbeth and Josh Willis have a pretty good idea of what they are talking about:

    http://pielkeclimatesci.wordpress.com/2010/04/19/further-feedback-from-kevin-trenberth-and-feedback-from-josh-willis-on-the-ucar-press-release/
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  15. The IPCC never did rigorous scientific analysis because they were never set to do that- They were set up to summarise the scientfic record which is not the same thing. If there was such a massive paper (it would have to be a meta-study), Skeptical Science would leap to point to it. The IPCC was a massive opportunity wasted to either prove or disprove or more likely indicate that the scientific tools/data is not able to evaluate whatever precise AGW hypothesis is formed. A theory is more vague than a hypothesis.
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  16. Tom:
    From Dr. Trenbeth's email:
    " Roger I don’t believe any of the current dozen or so estimates of ocean heat content are correct. The TOA estimates are probably closer to being correct but they too have problems. The data may be robust since 2005 but the analysis methods are not. Kevin"

    As I have stated, there are problems with OHC. I will just leave it at that as I will show you evidence, but I am not going to try to force you to think outside of the box per se.
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  17. cloa513
    "...not able to evaluate whatever precise AGW hypothesis is formed. A theory is more vague than a hypothesis."

    John, any other contributing writer, anyone who cares. I've just done a quick topic search on here for 'theory' and 'hypothesis' and didn't come up with anything directly relevant. (But a fair bit on consensus.)

    One constant skeptic/ denier/ contrarian theme is this silly dictionary diving, thesaurus stretching argy-bargy on personal interpretations of words like law, theory, hypothesis. They're often alluded to in posts and comments, but I think it would be a worthwhile rebuttal in its own right.

    "Only a Theory" or some such title would be a handy addition to the short titled references. I realise that you're all just sitting around idly waiting for suggestions on how to occupy your time, but someone might put this on the to-do list.
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    Moderator Response: (DB) Beware of suggestions (that's how I came to be a part of this great adventure). That's a good idea. Would you like to write a guest post on it?
  18. Camburn @13, if you mean the link provided @2, there is no discussion by you on that thread. I am not here to play some silly guessing game about which comments by other posters you may or may not agree with. If you have problems with Von Schuckmann et al (2009 or 2011) you should explicitly state them on the appropriate thread. Otherwise, as I have said, you are rightly considered to be merely hand waving.

    @14 and @15: you left out some quite revealing quotes.

    "I do not agree with your comments[that absent of measured ocean heat content is best interpreted as lack of OHC]. We are well aware that there are well over a dozen estimates of ocean heat content and they are all different yet based on the same data. There are clearly problems in the analysis phase and I don’t believe any are correct. There is a nice analysis of ocean heat content down to 2000 m by von Schuckmann, K., F. Gaillard, and P.-Y. Le Traon 2009: Global hydrographic variability patterns during 2003–2008, /J. Geophys. Res.,/*114*, C09007, doi:10.1029/2008JC005237. but even those estimates are likely conservative. The deep ocean is not well monitored and nor is the Arctic below sea ice."

    (Kevin Trenberth, 16/4/2010, my emphasis)

    So if you appeal to Trenberth's authority, the proper conclusion is that Von Schuckmann and Le Traon 2009 is superior to previous papers, but probably still underestimates OHC. That is hardly supporting your position.

    "Actually, Kevin, I do not think that they are all very different. It sounds like you are familiar with Lyman’s upcoming Nature paper and in both Figure 1 and Figure 2 of that paper, you can see that the estimates after 2005 all have the same basic variability. In fact, if these estimates did not include the XBT data, they would be even more similar in terms of their variability. I have personally verified that my own estimtes of OHC variability are very similar to those made by von Schuckmann, Eric Leuliette and another Argo-only analysis by Dean Roemmich for the post 2005 period. During this period, the technique and statistics used to interpolate the data is really not that important because the data coverage is very good. In fact, the same is true for the period of the 1990s. One of the main points of the Lyman Nature paper is that the data biases are by far the most important remaining error–much larger than the differences caused by different interpolation techniques or differences in the assumed statistics."

    (Josh Willis, 17/4/2010, my emphasis)

    So, you have one expert who thinks the analysis is inadequate, and that it underestimates OHC increase; and another who thinks the analysis is adequate, and that it shows significant OHC rise (as in Von Schuckmann and Le Traon 2009 and Von Schuckmann et al 2011). From this you conclude, "When looking at a lot of literature, the error bars overlap enough that about all that can be concluded is that the OHC is flat with a negative bias." In other words, from expert agreement that there is a positive trend in OHC, you conclude that there is a slight negative trend in OHC. No more needs to be said.
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    Response:

    [DB] Closed missing html tag.

  19. Camburn, when you go from...

    "I still stand that OHC of 0-700 meters is flat to negative."

    to

    "As I have stated, there are problems with OHC. "

    it's equivalent to saying, "I can use the data to say what I want, but it's not good enough for you to say anything different."

    Basically, you're having your cake and blowing it up, too. Is that what you mean by thinking outside the box?
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  20. Thanks DB. I realised as soon as I hit the button that you'd say something like this.

    I'm happy to have it on the to-do list. Unfortunately, we're in the middle of selling the house. Constant vacuuming, dusting and all the rest for inspections (as well as packing or discarding 30+ years accumulated stuff before moving) doesn't leave much brain space for real work.

    I promise to start assembling dot points and references and a few key paras. I'm a horribly prolix writer so it'll take me dozens of iterations to get it readable. (Or I'll give up and send it for someone competent to edit and polish.)

    Serves me right.
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  21. I know how to evaluate the likelihood of a given set of numerical parameters when a theory has been proved (by the probability that the observations would have given a result at least as distant from the prediction as what has been actually observed).

    But I have no idea of how to give a probability to the hypothesis that some theory is true. Do you have other examples in the history where this has been done ? I think that quantifying a likelihood can be done only for the numerical value of parameters, when you have a certitude that the underlying theory to handle them is true - you cannot quantify anything is you're unsure that the theory is true.
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  22. There is one part of the Conclusion that strikes me as particularly well-written, almost worth memorizing!

    It is: "their letters provide with a perfect example of the strategies deployed by climate "skeptics" to twist the debate and sow doubt in the minds of the public. BHS articulate their argumentation around the defense of an ideal of scientific method they believe in while clearly violating the rules they pretend to respect. Citing irrelevant quotes or taken out of their context, misunderstanding fundamental concepts, concentrating on precise points without looking at the broad picture, cherry-picking or even inventing scientific facts and data in order to provide with justifications to their hypotheses, etc."
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  23. Nitpick on "AGW theory". There really is no such thing. We have:

    1. a theory of how changing concentrations of GHG and associated feedbacks affect climate.

    2. an *observation* (not hypothesis or theory) that humans are dumping large quantities of CO2 into the atmosphere, and various projections of what that means for the future derived from applying #1.

    "AGW theory" is typically used by the denialsphere to emphasize the "A" part, which many want to believe is politically driven, from the physical underlying theory, for which no conspiracy theory fits.

    Let's not help them out. It's a small thing, but it annoys me.
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  24. Jarch-The Theory of Evolution is full of holes-with breaks in the evolutionary record & an inability to properly quantify the *rate* of evolution in various species. Yet we still accept the theory of evolution because its backed by the fossil record & by our knowledge of how genetics, anatomy & a host of other biological processes work. Compared to Evolution, the Theory of Anthropogenic Global Warming is much more robust & more easily quantifiable.
    So I see once again, Jarch, that your claims are completely without any substance. Indeed, they're utterly nonsensical & display a complete lack of knowledge of how science actually works.
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  25. Marcus, it seems to me again that you don't answer my questions : I said that I don''t know how to evaluate a likelihood that a given theory is true (I know only how to evaluate a confidence interval of numerical parameters using a proven theory), and you didn't offer the slightest clue to answer that - just imprecations.
    Now if you believe that there is a numerical method to compute this kind of likelihood, nothing prevents to apply it retrospectively to a past stage of knowledge. For instance how would you evaluate the "likelihood that the Earth is the center of the universe" with the knowledge people had in 1400 ? or the "likelihood that the simultaneity of time is independent of the observer " ? I have no idea how to compute that - and the result , if any, would be probably totally wrong.
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  26. "A theory is more vague than a hypothesis"

    'Vague' doesn't come into it. A hypothesis is advanced, and, if it has a close fit to observations, survives scrutiny over time, provides reasonable predictions that are observed, and is corroborated by other scientists looking at the matter in different ways, it advances to a formal recognition of its potential validity - it becomes a theory. As in: chaos theory, gravity theory, the theory of relativity, evolution theory, etc etc etc.
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  27. dhogaza, I have to agree that your comments are nitpicking. 'AGW theory' is vernacular, but it neatly encapsulates the larger issue - that human activity is causing the planet to warm. This is the central pillar of these here debates, and responding to criticisms about this issue is the basis of this website.

    I also agree that it's not a precisely accurate acronym for the scientific basis. I (lightly) propose that, like common vilifying terms that have been appropriated by those maligned by them (nigger, quuer), common usage of this acronym might render it less effective as a pejorative. As to the skeptics - there's no hope for the vast majority, and it's not worth tapping a few more keys to try and win them over with a different nomenclature. That siad, I don't use the phrase much myself - but then I'm usually arguing these days with skeptics on finer points rather than the overall theory. I previously used the term more often when I used to think a holistic debating approach was more effective.
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  28. I do think that Dr. Humlum et al may be correct on the problems of assigning a quantitative value for the probability of AGW. I think this is more a problem for the science of complex systems, not a massive flaw in "AGW theory". Some things are just too complex for us to assign definite values for.

    What really irks me in the opinion piece is this part;

    "The CO2-hypothesis as it is formulated right now does not even fulfills the requirements of science, so we are miles away from being able to calculate a meaningful certainty on it. The reason for its lack of scientific foundation is the lack of ability for the CO2-hypothesis to come with forecasts that can be checked now or within a couple of years' time."

    They seem to be trying to redefine science to exclude complex systems which take a long time to change, or are in the distant past. Things like cosmology, evolution and climate science. They take an extreme view of falsifiability which goes much further than Karl Popper's. Reading Popper talk about evolution in regard to falsifiability is quite enlightening, especially as his views change with time becoming more favourable to the idea that Darwin's theory is testable.
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  29. No surprises here. The Norwegian magazine that printed the article (Teknisk Ukeblad) is a denialist rag edited by a hardcore denier. Norway has become a hotspot for climate change denial, not surprising, since the country is a major exporter of oil and gas. A few cold Decembers have caused the public opinion to flip to anti science mode and the MSM is taking advantage by reprinting every denier lie known to man, no questions asked.
    The country sits at the Arctic circle, but December/January temperatures below freezing is now front page material almost every single day during the winter. Almost no mention of the warmest April on record, with folks going to the beaches and swimming in the ocean during the Easter Holiday up here at the latitude of Labrador.
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  30. "The AGW theory does not pretend that natural factors cannot affect the global climate."

    It's incredibly frustrating when I run into people arguing energetically that "climate changed without us before!" in order to rebuff the idea that we're a major driver of climate change now. What is so hard to understand about this? It boggles the mind.
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  31. "You can cite papers showing it is rising, I can cite papers showing it is cooling." --- Camburn at 05:33 AM on 23 May, 2011

    So, ISIWoK lists =ZERO= papers that even suggest global warming has ceased, let alone stopped, let alone are cooling. Camburn appears to know something no scientist on the planet does.
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  32. Classic read a bit of the paper, thought, not again,

    googled :"Humlum is at it again" Great heading

    .
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