• Russ R.

    I’d double check the data here. The green line on the left peaks at a higher level (above 0.0 deg C) than the one on the right.

    As an aside, has anyone offered an explanation for why the recent tree-ring proxy data have diverged so dramatically from temperature measurements?

  • Wally

    “As an aside, has anyone offered an explanation for why the recent tree-ring proxy data have diverged so dramatically from temperature measurements?”

    Because the calculations used to get temperatures from tree ring data are terrible. They have been manipulated as to hide the MWP and the little ice age. So its not surprising that they don’t match real temps…

    And the peak is probably not lining up with the 0 degree C mark because the absolute number used as “0” is different between the two graphs. The entry from this blog (linked at the bottom) does a much better job explaining it.

  • hunter

    The problem is that using trees as thermometers is a sorry use of tree rings, as presently done.
    Perhaps an isotope study of tree rings will be better. Perhaps.
    Briffa admitted the first part of this issue in the e-mails.
    The hockey teams knows that they are useless, as the e-mails show.
    but they bravely trudged ahead, with their junk science. AGW is too important to worry with things like honesty and truth.
    Our host spoke abou the isotope study in an earlier posting.

  • Fred from Canuckistan . . .

    “has anyone offered an explanation for why the recent tree-ring proxy data have diverged so dramatically from temperature measurements?”

    Because trees make lousy thermometers 🙂

  • ADiff

    What could affect tree rings? Just to start with…..


    Moisture levels

    Timing of moisture fluctuations

    Temperature anomalies outside of general fluctuation (rare ill-timed spring freeze, etc…)

    Disease affecting populations, communities or individual specimens

    Insect infestations or changes in predation patterns, ditto

    Soil changes, from unusual run-off events or flash flooding (chemical or physical soil change)

    Soil changes from alterations in soil biota (both microscopic and macroscopic creatures are synergistic in nutrient availability, changes in these will impact growth rates. Such changes can affect individuals, areas or entire populations)

    Fire

    Lightening strikes on individual specimens

    Crowding or Release (removal of competing neighbors)

    Changes in incidence of cloud cover over time in specific area of specimen

    Regular deposition of ash or dust in area of specimen (upwind fire, volcanism, &etc)

    Animal consumption of leaves and/or bark

    Baseline variations between individual specimens in growth rates (and responses to all of above)

    The challenges of obtaining enough specimens to control for all of the other factors makes it unlikely any growth data isn’t ‘more noise than signal’ unless one has extensive collections across geographic and temporal regions. Isolating individual signal elements is obviously not only challenging, but probably inevitably prone to unknown error levels as there’s just no good baseline for all the variables involved. And all this doesn’t even begin to address the various technical variables involved in deriving the measurements themselves…many of which are insignificant as well.

    Trees really are lousy thermometers.

    The thing about ‘high noise’ measurements, is they can usually be ‘represented’ as just about anything…provided one is willing to pretend noise is really signal, a fundamentally dishonest act. And in this case let’s not forget that Briffa went even further….when his speculative data failed to demonstrate what was desired, he ‘adjusted’ it (in the MWP period) to give desired politically correct results. When those adjustments, applied to other periods, resulted in obviously wrong results (i.e. recent rapid cooling) the problem was how to keep the adjustments where they yielded desired results, but not where they didn’t. The “trick” that solved that problem was to just throw those results out!

  • astonerii

    I’ll admit my ignorance and hope I can get educated about something.
    Who is Mail Online and how can it be considered a main stream media outlet? I have only recently heard of it and I seriously doubt that it has any reach into groups of people who have not already known for years the climate science is bunk. So, I would hope someone can tell me more about this site so I can understand how it gets MSM cred.

  • Leonard Weinstein

    ADiff,
    You left off CO2 variation. The work by Prof Beck demonstrated large land based CO2 variation over the years. Even if this was not representative of global average, it showed local land based values could vary a lot, and thus if CO2 changed growth rate locally, this also could have caused uncoupling from temperature. The same exact argument that says Beck’s data is not representative of global CO2 levels equally disqualifies tree data.

  • An Inquirer

    Hats off to ADiff for a good list, but even this list is not complete. A tree can be fertilized more than others if animals deposit their dung nearby. Such patterns can continue for decades until disturbed by predators, diseases, encroachment of humans . . . .

    BTW: Congratulations to the readers of this short blog. You now understand more about the hockey stick than 90% of the reporters who have repeated mentioned it in their articles.

  • Bill Radcliffe

    astonerii:

    Mail online is the web version of one of the highest circulation newspapers in the UK.

  • astonerii

    Bill Radcliffe:
    Thanks, not sure how much exposure the online version will get, I hope it is enough to force actual print media to print as well.

  • michel

    The Mail is a middle class (in the US sense) national tabloid sized paper, heavily oriented to family and health issues. It has a large readership among middle class and working women. It is to the right of center, probably by about as much as the Guardian is to the left. Its a much more serious paper than the the true red top tabloids, and actually publishes real stories, though along with gossip and sensational and speculative material. Less ‘serious’ than the so called broadsheets like Guardian, Telegraph, Independent, Times. It is generally despised and disliked by the UK left. But it is large circulation, particularly among women.

    For the Mail to publish a long story like this is a significant event and will have effects over time. The Mail generally is right in line with its readers opinions, it may lead a little on some issues, but it does not seek to be controversial, and its really the voice of a certain kind of middle England. Provincial, mainly Tory voting, suspicious of officialdom, ready to become indignant of anything they don’t care for, a little prurient in interests in scandal and the lives of others, hostile to the EU, not intellectual, very focused on daily life. This would be, disapprove of Afghanistan but support our boys territory.

    I haven’t been in the UK for several months, but it has seemed previously as if there was large scale but not loudly voiced skepticism of AGW among the classes of people who constitute the Mail readership. It may now be coming out into the open, and if the Mail takes up skepticism, it will do so stridently.

  • optimist

    This article *was* published in the paper version of the newspaper last Sunday — a prominent double-paged spread. This may be the UK’s biggest selling Sunday newspaper.

  • dearieme

    What you need to know about the Mail: Jim Hacker’s guide to the British papers (courtesy of “Yes, Prime Minister”).

    – The Daily Mirror is read by people who think they run the country;
    – The Guardian is read by people who think they ought to run the country;
    – The Times is read by people who actually do run the country;
    – The Daily Mail is read by the wives of the people who run the country;
    – The Financial Times is read by people who own the country;
    – The Morning Star is read by people who think the country ought to be run by another country;
    – And the Daily Telegraph is read by people who think it is.”

  • Bill Radcliffe

    dearieme:

    You left off the last line (given by Bernard, barely controlling his features). Jim Hacker (PM) asked “what about the Sun readers” (a very high circulation red top). Bernard replied “They don’t care who runs the country as long as she’s got big tits”.

  • dearieme

    Bill, I intended a modicum of propriety. 🙂

  • ADiff

    Leonard,

    Thanks for adding that one (CO2)! I’m not familiar with its fluctuations over time, but considering its central role in plant metabolism and relative atmospheric scarcity, it’s intuitive it would be a significant factor, which proposition I’ve heard.

    The list was just off-the-top, and no doubt there are others as well!

    Beyond methodological sampling issues, and the obvious signal-to-noise problem, variable isolation, just from this incomplete list, seems not just daunting, but perhaps impossible.

    But as is the case with high SNR data, it’s always to possible to find some way to hear “Paul is dead” one way or another….if one wants to badly enough!

  • ADiff

    Correct that to read “low SNR data”….

    Weren’t the sample sets in these dendro studies rather small?