Tree Rings
Contact person:
Dr. Zoltán Kern
In the temperate and cold climate zones, as well as in parts of the subtropics, a dormant period and a productive growing season are clearly distinguished within a calendar year. Such conditions create clearly identifiable anatomical differences in the wood tissue. The annual increment produced in a calendar year appears as tree rings in the radial cross-section.
By knowing the calendar date corresponding to a particular tree ring in a tree-ring sequence, we can assign precise calendar dates to the preceding rings one by one, and use the physical (e.g., width, density) or chemical (e.g., 13C/12C ratio, Pb concentration) parameters to construct a time series.
By combining the chronology derived from living trees with measurement series from older, dead trees, a dataset much longer than the biologically possible lifespan of trees can be established. The great advantage of tree rings compared to other climate proxy data lies in the precise age control and annual (sub-annual) resolution.