Peanut Gallery for Great debate: radiocarbon dating, Mindspawn and Coyote

The debate has begun, and, as we usually have a thread to comment on the posts, I propose these guidelines:

1. Great Debate participants -- Coyote and Mindspawn -- should not post comments here, they have the GD thread for making their case.
2. Participants here should limit their comments to the contents of the posts on the GD thread.

Enjoy

in Message 3 mindspawn claims: Curiously, the comments by Dr. Grissino quoted refer to why growth rings have varying widths:

quote:

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The Principle of Limiting Factors

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As used in dendrochronology, this principle states that rates of plant processes are constrained by the primary environmental variable(s) that is most limiting. ...

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The variation in ring width is a separate issue from the occurrence of growth rings in ecologies with very distinct annual changes, such as winter and summer on top of the Sierra Nevada mountains, or where deciduous trees have leaves that die in an annual cycle, such as the Oaks in Ireland and Germany.This, of course, is also why certain species and growth areas are selected over others when a dendrochronology system is determined for providing age data.In addition Mindspawn fails to go on and quote Grissino on how the problems he points out are dealt with in making a good dendrochronology.http://web.utk.edu/~grissino/principles.htm#3

quote:

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The Principle of Aggregate Tree Growth

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This principle states that any individual tree-growth series can be "decomposed" into an aggregate of environmental factors, both human and natural, that affected the patterns of tree growth over time. For example, tree-ring growth (R) in any one year (indicated by a small "t", where t could be "1" for year 1, and "2" for year 2, etc.) is a function of an aggregate of factors:

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1. the age related growth trend (A) due to normal physiological aging processes
2. the climate (C) that occurred during that year
3. the occurrence of disturbance factors within the forest stand (for example, a blow down of trees), indicated by D1,
4. the occurrence of disturbance factors from outside the forest stand (for example, an insect outbreak that defoliates the trees, causing growth reduction), indicated by D2, and
5. random (error) processes (E) not accounted for by these other processes

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The Principle of Site Selection

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... This principle states that sites useful to dendrochronology can be identified and selected based on criteria that will produce tree-ring series sensitive to the environmental variable being examined. ...

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There is more on how cross-dating, replication and other methods are used to generate a good dendrochronology.The conditions cited for poor growth ring data do not apply, for instance, to the Bristle-cone Pine high in the Sierra Nevada mountains, nor to the deciduous Oak trees in Ireland and Germany.The problem for mindspawn is that he doesn't have to just question the accuracy, but he needs to show that the dendrochronologies are in fact inaccurate.Given that the Bristle-cone Pine dendrochronology from Sierra Nevada, the Oak dendrochronology from Ireland, and the Oak dendrochronology from Germany agree within 0,5% over 8,000 years of record, what mindspawn needs to demonstrate what specific type of events could affect each dendrochronology in exactly the same way in spite of them being in 3 diverse locations in the world and two different types of trees (one pine -evergreen- and the other oak -deciduous), and two significantly different ecologies.It is the correlations that show that the chronologies are accurate.Edited by RAZD, : finishingEdited by RAZD, : subtitle

Thread copied to the Peanut Gallery for Great debate: radiocarbon dating, Mindspawn and Coyote/RAZD thread in the Coffee House forum, this copy of the thread has been closed.