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Wikipedia as a source

  1. Sep 27, 2009 #1

    D H

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    Wikipedia has been uniformly denounced as a non-reputable source for discussions on science of any kind, let alone discussions in this Earth sciences forum. Here is a nice little graph from Wikipedia showing an apparent strong correlation between global temperature and atmospheric CO2 concentration:

    800px-CO2-Temp.png

    So if Wikipedia is a disreputable source, why did I use it as a source in this post? The reason: The United Nations Environment Programme used this very image in its "Climate Change Science Compendium 2009" report. See figure 1.3 on page 5 of the report, with attribution "Hanno 2009".

    McMullen, C.P. and Jabbour, J. (2009). Climate Change Science Compendium 2009. United Nations Environment Programme, Nairobi, EarthPrint. http://www.unep.org/compendium2009/PDF/compendium2009.pdf [Broken]

    At least the authors of this compendium could have been honest and cited the source as Wikipedia.
    http://commons.wikimedia.org/wiki/File:CO2-Temp.png
    Source: graph drawn by Hanno using data from different sources​


    With junk like this, is it any surprise that people question the science behind AGW?
     
    Last edited by a moderator: May 4, 2017
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  3. Sep 27, 2009 #2

    mgb_phys

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    It depends where the original data from the chart came from.
    In this case wiki is simply reformatting the data (assuming the author of the graph didn't edit the data). Is kinko's a reliable source? If I photocopy "On the Electrodynamics of Moving Bodies" does that make E=mc^2 wrong?

    If somebody took the data from a reputable source, created a graph and included it in wiki then it is as reputable as the original source - that another report simply took the graphic is probably un-profesional but they did credit the source.
     
  4. Sep 27, 2009 #3

    D H

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    No, they didn't, at least not in any professionally recognized form. That report ends with nine pages of references. The source for the cited graph is nowhere to be found in those references.
     
  5. Sep 27, 2009 #4

    mgb_phys

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    Sorry I misunderstood - I thought you meant they had listed wiki as the source of the graph rather than the original report it was from.

    There is a lot of lazy report writing out there - especially for outfits like the UN which seem to exist to give work to report writers. It's not necessarily malicous just cheap!
    Still at least they didn't invade Iraq because of some 'intelligence' they foun on the internet.
     
  6. Sep 27, 2009 #5

    Xnn

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    DH;

    Just because Wikipedia cited the same source as the UN report did does not mean UN report (or the original source) is not reputable.

    In this instance the original source was Hanno, which the UN cited; so there is nothing wrong with the UN's report.

    Actually, it would have been wrong for the UN to cite Wikipedia as a soure, since Hanno was the originator.
     
  7. Sep 27, 2009 #6

    D H

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    That's pure crap. I'm surprised your computer didn't undergo spontaneous combustion after you typed nonsense like that into it.

    Just browsing the report, figure 2.1 on page 15 cites "Source: WGMS 2008a". Looking in the list of references I see
    WGMS (2008a). Global glacier changes: facts and figures. UNEP/World Glacier Monitoring Service, Zurich ​
    A random paragraph from that page says
    Documentation of this trend has been building for the last century and studies of glaciers and ice caps are becoming more sophisticated with new satellite-based observation technologies and attempts to distinguish glacier responses to multiple variables (WGMS 2008a, WGMS 2008b, Braithwaite et al. 2009). Evidence from increasing loss rates is becoming stronger. In the European Alps, for instance, overall glacial volume reduced by about one per cent per year from 1975 to 2000 and between two and three per cent since the turn of the millennium (Haeberli 2007). ​
    I can find each of WGMS 2008a, WGMS 2008b, Braithwaite et al. 2009, and Haeberli 2007 in the list of references. So why don't I find Hanno 2009 in the list of references? Answer: The graph did not come from a reputable source. In fact, even the 2009 part isn't correct.
     
  8. Sep 27, 2009 #7

    Xnn

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    DH;

    I'll let you in on a little secret: Wikipedia isn't a real person.
     
  9. Sep 27, 2009 #8

    D H

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    I'll let you in on another little secret: Neither is the Annals of Glaciology, or any of the other multitude of publications that the bibliographic references in the main body of the report link to in the references section.

    I'll let you in on another little secret: Scientists in fields other than climatology have lost their jobs and have been essentially blacklisted for acts just like this. Fabrication of evidence is scientific fraud.

    BTW, I retract part of what I said in post #6. Braithwaite et al. 2009 is not listed in the references, either.
     
  10. Sep 27, 2009 #9
    It seems that Hanno is a Wikipedia user who can be found in the Norwegian and sometimes the German Wikipedia, lol. http://commons.wikimedia.org/wiki/User:Hanno" [Broken]
     
    Last edited by a moderator: May 4, 2017
  11. Sep 27, 2009 #10

    D H

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    Correct. That of course is the user's wikipedia handle. His full name is Hanno Sandvik. If Hanno Sandvik was a professional soccer player, referring to him by his first name only would be fine. Last I read, referencing someone by first name only in a supposedly scientific work is not standard practice.
     
    Last edited by a moderator: May 4, 2017
  12. Sep 27, 2009 #11
    Not true.

    I suspect that the person who uploaded the graph is himself the scientist who made that graph for the scientific report itself. Wikipedia has a lot of professional scientists as its contributors. Since 2005/2006 a huge number of professional scientists have started to conribute to wikipedia and the quality of wikipedia articles (in the sense of being scientifically accurate, not necessarly w.r.t. being "encyclopedic") has improved so much that it is the best easy to access, scientific source of information.

    I have myself corrected errors in wiki articles before the cited article's erratum was published (and even before the arXiv version was corrected). So, in some cases, it is the only source that will give you the correct information.
     
  13. Sep 27, 2009 #12

    D H

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    Name one scientific journal that accepts wikipedia references amongst the citations.

    I suspect that the person who uploaded the graph is a long-time contributor to wikipedia and uploaded the graph almost four years ago, on 6 December 2005. Look at the timetag on the reference.
     
  14. Sep 27, 2009 #13
    I'm sure that I could get away with a Wikipedia reference to a specific article version (instead of linking to the current version which could be affected by temporary vandalism or temporary quack edits) in the Physical Review.

    I have never done this, but I have a few times before given links to webpages, so I don't see what would be so problematic about giving a wiki link, if the text on the wiki page is better suited for the readers than some standard review article or book.

    Also, from my personal experience, journals such as the Physical Review do not strictly enforce any guidelines about what is allowed or not. If you as the Author write a good article, the Referee is unlikely to object on some minor irrelevant point, just because the journal guidelines are not met.
     
  15. Sep 27, 2009 #14

    mheslep

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    In no objective way can you defend using 'best' as a modifier of 'scientific' here, only 'easiest'. BTW, we have scientists on PF that refuse to participate in Wiki.
     
  16. Sep 27, 2009 #15

    mheslep

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    Good catch DH. Outrageous that the Compendium allowed this, though their first name basis friend 'Hanno' must be pleased.
     
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  17. Sep 27, 2009 #16

    ideasrule

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    And, on the other hand, we have scientists who graduated from Ivy League schools contributing to Wikipedia for the benefit of others. Some people are willing to sacrifice hours every day to make Wikipedia the best it can be, even though they can't hope to get any career or monetary benefit from it. It's quite an insult to these volunteers to denounce an article or a piece of information simply because it happened to be on Wikipedia.

    The graph in question was based on reputable sources, which Hanno cited, and is no less reliable than those sources. That said, the journal's use of the image is highly questionable. First of all it violates Wikimedia Commons' license on the image (http://creativecommons.org/licenses/by-sa/3.0/legalcode), which says:

    "You may Distribute or Publicly Perform the Work only under the terms of this License. You must include a copy of, or the Uniform Resource Identifier (URI) for, this License with every copy of the Work You Distribute or Publicly Perform."

    "You must...keep intact all copyright notices for the Work and provide...to the extent reasonably practicable, the URI"

    Second, how hard could did possibly have been to check Hanno's sources and redraw the graph? I agree that this belies the author's extreme laziness.
     
  18. Sep 27, 2009 #17

    D H

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    Not my catch. The "denier" crowd is all over this. Interesting, the only denialism going on is that being perpetrated by the true believers.
     
  19. Sep 27, 2009 #18

    mheslep

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    Not at all. The thesis here is not that Wiki is all trash, on the contrary it is wonderfully handy quick resource. The thesis is that Wiki is flawed, because along with all the expert contributions crackpot and agenda driven themes remain, as I'm sure the expert contributors and you are well aware. Thus when the scientific standard needs to be very high, as for published journals, Wiki doesn't cut it.
     
  20. Sep 27, 2009 #19

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    Encyclopedias are fine as a reference for little kids. They are fine as a starting point for research by older kids. However, every student reaches a point in their education when using any encyclopedia as a reference is no longer allowed. Using an encyclopedia is anything but fine for a scientific paper. The reason is simple: Encyclopedias are not supposed to be the place for publishing original research. Wikipedia is first and foremost an encyclopedia, and it has a very strong rule against publishing original research.

    http://en.wikipedia.org/wiki/Wikipedia:No_original_research
    • Wikipedia does not publish original thought: all material in Wikipedia must be attributable to a reliable, published source.
    • Articles may not contain any new analysis or synthesis of published material that serves to advance a position not clearly advanced by the sources.
    Emphasis mine. More on this below.

    The graph is less reliable than those sources. From http://commons.wikimedia.org/wiki/File:CO2-Temp.png, "Source: graph drawn by Hanno using data from different sources." In other words, the graph is a clear violation of Wikipedia's No Original Research rule. It is a synthesis of published material that advances a position not clearly advanced by the sources.

    Before I posted the original post I looked at the global warming pages in the English version of Wikipedia to find the article in which the graph is used. I couldn't find one. A likely reason is that someone at Wikipedia removed the graph from whatever pages used to reference it They did not delete the graph itself from the Wikipedia commons.
     
  21. Sep 27, 2009 #20

    ideasrule

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    The policy on original research has a section devoted to synthesis, which states: "Do not combine material from multiple sources to reach or imply a conclusion not explicitly stated by any of the sources." "Imply a conclusion" is the key phrase; using multiple resources is not synthesis by itself because every good article references more than one source. Hanno's graph is borderline because on one hand, the sources might have been chosen for a reason, but on the other, the graph doesn't advance any clear position. It doesn't tell us whether CO2 concentration influences temperature or whether temperature influences CO2 concentration; it doesn't say whether one causes the other or is merely correlated with the other. Since the correlation between CO2 concentration and temperature is not controversial, the graph is good for illustration purposes.
     
  22. Sep 27, 2009 #21

    ideasrule

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    An easy way to see what articles use the graph is to use the CheckUsage app: http://toolserver.org/~daniel/WikiSense/CheckUsage.php?i=CO2-Temp.png&w=_100000#end

    You're right in saying that no Wikipedia articles use it, but wikis in other languages do.
     
  23. Sep 27, 2009 #22

    sylas

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    I agree that the use of this graph was pretty dreadful.

    There's all kinds of problems with it. The referencing is inadequate in the compendium, and also in the wikipedia page. I had a quick try at sorting out the paper trail, and it's not easy. "Hanno" cites the temperature data to Jones and Mann (2004). It's easy enough to find the data; it is in figure 5 of that paper. Except that the scale is different. For some reason, Hanno used an absolute temperature scale. I have no idea why. Furthermore, Hanno omitted the error bars which were in the original... and they are quite significant. The particular data in Jones and Mann is properly cited, back to Jones and Mann (2003).

    There's another problem: the graph by Hanno also shows a CO2 trend. But then how are the two vertical axes aligned? I presume he's picked out a scale that gives the best correlation.

    The problem here is, however, that the association of CO2 with temperature is not based on correlation; and there are other factors than CO2 to consider.

    All told, yuck! This is pretty lazy by the authors of the compendium. It would have been straightforward to give a proper primary reference with the same basic information, and a better graph.

    ----

    On the other hand; neither Wikipedia not the compendium are primary sources, and neither one is an instance of the "science behind" anthropogenic global warming (AGW). That science stands or falls on its own merits; and not on how well it is described in secondary summaries.

    The biggest issue here is that this use of the graph was lazy; not that the science is actually suspect. I realize some people here are suspect about various aspects of the science behind global warming; but that is a different discussion, and should be considered by looking at primary sources. This use of a badly sourced graph is not a case of bad science, but of poor science writing. The science behind the graph stands up just fine. To disagree with that would require looking at the science itself.

    In this case, the science to consider is as follows:
    • The various attempts to reconstruct global temperature trends over the couple of millenia.
    • The reconstruction of atmospheric CO2 over the last couple of millennia.
    • The physics behind the association of CO2 and temperature -- the strong correlation is not the primary evidence for this association, but stands rather as a test of the correlation that is expected given the underlying science.

    This would mean considering the following references, or others like them:
    • Mann, M. E., and P. D. Jones (2003), Global surface temperatures over the past two millennia, in Geophys. Res. Lett., 30(15), 1820, doi:10.1029/2003GL017814. (Publicly accessible preprint).
      Figure 2c shows the temperature data used by Hanno; how this is obtained is described in the paper.
    • Jones, P. D., and M. E. Mann (2004), Climate over past millennia, in Rev. Geophys., 42, RG2002, doi:10.1029/2003RG000143.
      Source given by Hanno for temperatures. Data shown in Figure 5c, cited to Mann and Jones (2003).
    • Climate Reconstructions repository at NCDC (NOAA), with data available for hundreds of papers, including the Mann and Jones (2003), and Jones and Mann (2004). You can use this to obtain numbers and play around yourself, with this and a lot of other data.
    • Etheridge, D.M. et al. (1998). Historical CO2 records from the Law Dome DE08, DE08-2, and DSS ice cores. In Trends: A Compendium of Data on Global Change. Carbon Dioxide Information Analysis Center, Oak Ridge National Laboratory, U.S. Department of Energy, Oak Ridge, Tenn., U.S.A.
      This is the source of CO2 data used by Hanno. Linked page includes datasets.
    • Knutti, R., and L. Tomassini (2008), Constraints on the transient climate response from observed global temperature and ocean heat uptake. in Geophys. Res. Lett. 35, L09701, doi:10.1029/2007GL032904. (Publicly available preprint)
      This estimates the transient climate response (TCR; per 2xCO2) as being from 1.11-2.34, with a best estimate of 1.6 degrees. The IPCC 4th AR estimates 1-3 degrees. (All 90% confidence bounds.) The difference between TCR and equilibrium sensitivity is briefly explained in [post=2362326]msg #69[/post] of thread "Playing Devil's advocate on climate", with references.
    See also plenty of references and background on the physical basis for quantifying the link between temperature and CO2 in the thread [thread=307685]Estimating the impact of CO2 on global mean temperature[/thread].

    A more meaningful comparison of CO2 with temperature would compare the logarithm of CO2 with anomalies. The jump in CO2 shown by Hanno is from 280ppm to 380ppm. As logarithms, this is log2(380/280) = 0.44. Using a TCR of 1.6 (range 1.1 to 2.4) gives a temperature response of about 0.7 degrees (range 0.5 to 1.0). Hanno's graph uses about 0.67 degrees between 280ppm and 380ppm, which is reasonable enough. So actually the graph is not a bad guide to the expected link of temperature and CO2... except that it omits all error bounds, all justification of the scale link, and the logarithmic nature of the relation.

    It's not that the science is bad, or even that the graph is particularly misleading. Its fair enough as a simple non-technical illustration. But the compendium would have been much better to actually USE the science, rather than the image they chose.

    Cheers -- sylas
     
    Last edited: Sep 27, 2009
  24. Sep 28, 2009 #23
    I think wikipedia is an extremely useful resource for general knowledge purposes. If i see something on wikipedia unsourced, i know to ignore it. If something sounds questionable, I can check the source, see for myself, google that source, read more on the subject, etc. I think an overview of the discussion on an article is essential to understanding what might be controversial. It is not a final source, but it's a great starting point. From what the OP described, the graph was a clear violation of wikipedia's policies. I think it might be the case that an article on global warming attracts alot of cracpot editors, so it it locked moreso then a normal article would be.
     
  25. Sep 28, 2009 #24

    D H

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    You missed the point of the original post, Galteeth. The graph in question was used in an official UN report. To make things worse, it was not properly cited. To make things even worse, that graph appears to contravene wikipedia rules against original research.

    There is a larger issue here, and that is what constitutes a valid reference for the purposes of this particular part of Physics Forums. [thread=280637]The PF Earth Sciences policy[/thread] states
    The problem with this policy is that the reputable sources are not all that reputable. This latest UN report is but one example of that.
     
  26. Sep 28, 2009 #25

    vanesch

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    Of course, and even in peer-reviewed literature (which a UN report is not really) there are errors and even outright wrong claims.

    Peer-review IS NOT a guarantee for quality. But it should have, on average, a higher level of quality. At least a lot of junk is rejected in peer-review. Not all. There are no guarantees. Just some means to try to elevate the level of quality. That's all.

    Moreover, the UN report is not a scientific report, as it talks about policies. From the moment you talk about policies, you left the area of pure, investigating, science. In other words, this UN report is not a scientific publication.
     
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