(den-droh-cruh-NOL-uh-gee) means “the study of tree time.” Usually called tree-ring dating, dendrochronology is a science based on the fact that every growth season a tree adds a new layer of wood to its trunk.Over time, these yearly growth layers form a series of light and dark concentric circles, or tree rings, that are visible on cross sections of felled trees.Example: analyzing ring widths of trees to determine how much rainfall fell per year long before weather records were kept.
Radiocarbon dates which have been corrected--or rather, calibrated--by comparison to dendrochronological records are designated by abbreviations such as cal BP, or calibrated years before the present.
With the aid of databases, rapid exchange of information, increased interest in vernacular buildings, and the sponsorship of national organizations like English Heritage or the CRMH (Centre de Recherches sur les Monuments Historiques) in France and Belgium, a quantum leap has occurred in the number of monuments now dated by this method.
Most important for architectural history, this tool gives us objective (scientific) dates for a wide range of medieval buildings against which we can compare our ideas of stylistic change and technological evolution.
Example: analyzing the effects of air pollution on tree growth by studying changes in ring widths over time.
The science that uses tree rings to date earth surface processes that created, altered, or shaped the landscape.