Dendrochronology radiocarbon dating calibration
Some critics of dendrochronology suggest that the process of pattern-matching is highly error-prone.Are the long tree-ring chronologies inaccurate due to the inability of dendrochronologists to accurately match tree-ring patterns?The pattern of radiocarbon in the rings showed a maximum divergence, even at very old ages, of only around 40 years.This objective, quantitative test of dendrochronology showed it to be reliable and accurate.Because radiocarbon is everywhere the same in the atmosphere at any given time, tree rings which grew in the same year should have the same amount of radiocarbon.Furthermore, radiocarbon in the atmosphere fluctuates from year to year in a somewhat erratic fashion.The patterns in America could not bias the work on patterns in Europe, because the specimens came from two different local climates, separated by an ocean.
That is, rings of the same putative dendrochronological age were found to contain the same amount of radiocarbon, and to give the same pattern of fluctuations over time.The following article is abstracted from The Biblical Chronologist Volume 5, Number 1. The science of constructing chronologies from tree rings is called dendrochronology. Modern trees are known to produce one growth ring per year. (The idea that ancient trees grew more than one ring per year will be discussed below.) Therefore, by coring a living tree and counting rings from the present backwards, it is possible to determine the year in which each ring grew. The bristlecone pines in the White Mountains of California live to extremely old ages, some in excess of 4,000 years.The University of Arizona dendrochronology lab sports a (no longer living) specimen which contains over 6,000 rings.We could discuss the details of pattern-matching technique or the probability of error, but there is another, more quantitative way, to determine if the long tree-ring chronologies are accurate or not.