Dendrochronology and radiocarbon dating
Checked through a variety of methods independent of tree-ring growth, this principle has proved to be valid.
The climatic changes or patterns in specific geographic areas can be traced by the study of old living trees.
Dendrochronology can help solve many environmental problems.
Tree-ring analysis can be used in a variety of ways to diagnose pollution effects in its early stages, and to help adjust certain irrigation projects.
A principle basic to any study of the past is the principle of "uniformity in the order of nature", first proposed by James Hutton in 1785.
Statistical Analysis A number of tree samples must be examined and cross dated from any given site to avoid the possibility of all the collected data showing a missing or extra ring.
A chronology (arrangement of events in time) can be made by comparing different samples.
Using a boring tool, a long slender core sample about .423 centimetres in diameter is extracted.
When applying this principle to dendrochronology, it says that the variations in conditions present today must have been present in the past.
This does not mean to say that the conditions are exactly the same but that similar kinds of influences affected the similar kinds of processes.Yearly climatic changes can be seen by first removing, statistically, the gradual changes associated with the age of the tree.