Automated Crossdating With a Modified Version of the Dendrochronology Program CROS

ABSTRACT The basic principle of dendrochronology involves matching patterns of tree‐ring widths, with the objective of dating wood of unknown age. The various crossdating procedures rely on statistical methods. The legacy CROS program written in FORTRAN IV contains algorithms, variants of which have been incorporated into modern crossdating programs with a graphical interface. The new CROS25 program written in FORTRAN 2018 is a modified version of the CROS program and is designed for automated crossdating without manual keystroke input. In the automated procedure, the regional set of dated series file names is input only once, and it is used in all the following automated runs with a new undated series. This saves much time compared with manual keystroke commands in the conventional crossdating programs with a graphical interface.