Scientific American, Mann hockey stick graph

Discussion in 'Environment' started by Old Rocks, Nov 7, 2009.

  1. Old Rocks
    Offline

    Old Rocks Diamond Member

    Joined:
    Oct 31, 2008
    Messages:
    46,465
    Thanks Received:
    5,410
    Trophy Points:
    1,840
    Location:
    Portland, Ore.
    Ratings:
    +10,305
    Hmmm........ Every time someone does a serious study on this, the Hockey Stick Graph just gets more confirmation.


    Novel Analysis Confirms Climate "Hockey Stick" Graph: Scientific American

    The “hockey stick” graph has been both a linchpin and target in the climate change debate. As a plot of average Northern Hemisphere temperature from two millennia ago to the present, it stays relatively flat until the 20th century, when it rises up sharply, like the blade of an upturned hockey stick. Warming skeptics have long decried how the temperatures were inferred, but a new reconstruction of the past 600 years, using an entirely different method, finds similar results and may help remove lingering doubts.

    The hockey stick came to life in 1998 thanks to the work of Michael Mann, now at Pennsylvania State University, and his colleagues (and many other climate scientists who subsequently refined the graph). Reconstructing historical temperatures is difficult: investigators must combine information from tree rings, coral drilling, pinecones, ice cores and other natural records and then convert them to temperatures at specific times and places in the past. Such proxies for temperature can be sparse or incomplete, both geographically and through time. Mann’s method used the overlap, where it exists, of recent proxy data and instrument data (such as from thermometers) to estimate relations between them. It calculates earlier temperatures using a mathematical extrapolation technique [see “Behind the Hockey Stick,” by David Appell, Insights; Scientific American, March 2005].
     
  2. FactFinder
    Offline

    FactFinder VIP Member

    Joined:
    Mar 1, 2009
    Messages:
    2,641
    Thanks Received:
    202
    Trophy Points:
    83
    Ratings:
    +237
    You mean it is trying for a comeback after the thrashing it took for its manipulative approach to the data..
     
  3. FactFinder
    Offline

    FactFinder VIP Member

    Joined:
    Mar 1, 2009
    Messages:
    2,641
    Thanks Received:
    202
    Trophy Points:
    83
    Ratings:
    +237
    http://www.scientificexploration.org/journal/jse_19_2_deming.pdf

    Global Warming, the Politicization of Science,
    and Michael Crichton's State of Fear

    A direct attack on Mann et al. (1999) appeared later in 2003. Two Canadian
    scientists, Stephen McIntyre and Ross McKitrick, tried to replicate the results of
    Mann et al. (1998), but were unable to do so. In a paper published in Energy &
    Environment, they claimed:
    The data set of [Mann et al., 19981 . . . contains collation errors, unjustifiable truncation
    or extrapolation of source data obsolete data, geographical location errors, incorrect
    calculation of principal components, and other quality control defects. (McIntyre &
    McKitrick, 2003: 751)
    McIntyre and McKitrick also found that Mann et al.'s (1998) results could not
    be supported by the data.
    The particular "hockey stick" shape derived in the [Mann et al., 19981 proxy
    reconstruction . . . is primarily an artifact of poor data handling, obsolete data and
    incorrect calculation of principal components. (McIntyre & McKitrick, 2003: 751)
    An even more serious critique of the Mann et al. (1998, 1999) climate
    reconstructions appeared in Science in October, 2004. Von Storch et al. (2004)
    Global Warming and State of Fear 25 1
    pointed out that the methodology used by Mann et al. (1998, 1999) was flawed.
    Their reconstruction technique tended to dampen out, and thus obliterate, past
    temperature changes. Although the analysis by von Storch et al. (2004)
    published in Science was damning, the language was diplomatic.
    The centennial variability of the Northern Hemisphere temperature is underestimated
     
  4. FactFinder
    Offline

    FactFinder VIP Member

    Joined:
    Mar 1, 2009
    Messages:
    2,641
    Thanks Received:
    202
    Trophy Points:
    83
    Ratings:
    +237
    Now one can see why the terror mongers wish to discredit Energy &
    Environment
     
  5. RetiredGySgt
    Offline

    RetiredGySgt Platinum Member

    Joined:
    May 6, 2007
    Messages:
    39,518
    Thanks Received:
    5,898
    Trophy Points:
    1,140
    Location:
    North Carolina
    Ratings:
    +8,928
    Unbelievable , after it was rightfully driven off the stage for being WRONG, we have old rocks trying to claim it is right. Usual tactics of the left, if you just keep saying something is true long enough some people will believe you. If you are proven wrong, wait a little bit and make the claim again later, then demand "evidence" your claim is wrong.
     
    • Thank You! Thank You! x 2
    • Funny Funny x 1
  6. Si modo
    Offline

    Si modo Diamond Member

    Joined:
    Sep 9, 2009
    Messages:
    41,538
    Thanks Received:
    6,382
    Trophy Points:
    1,810
    Location:
    St. Eligius
    Ratings:
    +8,703
    Your desperation is rather cringeworthy, Rocks.
     
  7. eagleseven
    Offline

    eagleseven Quod Erat Demonstrandum

    Joined:
    Jul 8, 2009
    Messages:
    6,518
    Thanks Received:
    1,254
    Trophy Points:
    48
    Location:
    OH
    Ratings:
    +1,255
    [​IMG]

    You want to base our economic policy, which will affect billions of people across the globe, upon tree-ring predictions? Do you believe in palm-reading as well?
     
    • Funny Funny x 1
  8. CrusaderFrank
    Online

    CrusaderFrank Diamond Member

    Joined:
    May 20, 2009
    Messages:
    81,170
    Thanks Received:
    14,903
    Trophy Points:
    2,210
    Ratings:
    +36,905
    As a strict science, Climatology falls solidly between palmistry and phrenology.
     
  9. CrusaderFrank
    Online

    CrusaderFrank Diamond Member

    Joined:
    May 20, 2009
    Messages:
    81,170
    Thanks Received:
    14,903
    Trophy Points:
    2,210
    Ratings:
    +36,905
    So as an atmospheric molecule, we can still safely state that CO2 hockey sticks up to a rounding error, a trace element.
     
  10. mdn2000
    Offline

    mdn2000 BANNED

    Joined:
    Sep 27, 2009
    Messages:
    3,766
    Thanks Received:
    278
    Trophy Points:
    0
    Location:
    conservative hell california
    Ratings:
    +278
    Old Crock is a big idiot, once again old crock proves himself wrong, you have to read the article mornon.

    More variabllity, less reliability, looser parameters so the data is easier to manipulate

    His analysis as in his opinion of his data, suggests is also not proof, given more variability of course his analysis can suggest anything.

    May help as in does not, this analysis using a novel approach does not remove the lingering doubts, hence the use of the word may.

    data is admitted sparse and incomplete, no wonder at best this may help but not remove the doubt about global warming.

    See anything that even suggests proof in this quote

    This new method makes assumptions, nice non-scientific method.

    So these folks are not sceintists, assuming, attempting, estimating, what they beleive probable.

    To maybe prove and assume an estimate of what they beleive

    This article proves old crock is wrong once agaian.

    This article states that these global warming kooks assume, use proxy data, estimate, manipulate, the data to get a preconceived result.

    This article states its just a guess that the last decades were warmer.

    A guess, you beleive this, and in took millions of manipulations to even get to a guess that still is just an estimate, at best.

    So the last decades are not even proven warmer.
     
    • Thank You! Thank You! x 1

Share This Page

Search tags for this page

scientific american graph