Sturt Manning is leading investigations into the timelines of ancient events, using tree ring data to refine the widely used radiocarbon dating method. In research published Aug. He and collaborators, including Brita Lorentzen, research associate in the Cornell Tree Ring Laboratory , used IntCal20, an international calibration curve released this year, in search of higher-resolution historical chronologies. Radiocarbon dating measures the decomposition of carbon, an unstable isotope of carbon found in all organic matter and created by cosmic radiation.
ORAU - Calibration
Dendrochronology or tree-ring dating is the scientific method of dating tree rings also called growth rings to the exact year they were formed. As well as dating them this can give data for dendroclimatology , the study of climate and atmospheric conditions during different periods in history from wood. Dendrochronology is useful for determining the precise age of samples, especially those that are too recent for radiocarbon dating , which always produces a range rather than an exact date. However, for a precise date of the death of the tree a full sample to the edge is needed, which most trimmed timber will not provide. It also gives data on the timing of events and rates of change in the environment most prominently climate and also in wood found in archaeology or works of art and architecture, such as old panel paintings. It is also used as a check in radiocarbon dating to calibrate radiocarbon ages.
The Radio-Carbon Dating of the Voynich MS
The parameters used for the corrections have been obtained through precise radiocarbon dating of hundreds of samples taken from known-age tree rings of oak, sequoia, and fir up to about 13, BP. Beyond that, back to about 55, BP, correlation is made using multiple lines of evidence. This information is compiled into internationally accepted databases which are updated on occasion. The present databases are IntCal20 northern hemisphere , SHCal20 southern hemisphere and Marine20 marine environments. These likelihoods are graphically represented by a shaded grey area on the plot and by percentage values reported next to each range.
Radiocarbon dating, invented in the late s and improved ever since to provide more precise measurements, is the standard method for determining the dates of artifacts in archaeology and other disciplines. A new paper led by Cornell University points out the need for an important new refinement to the technique. The outcomes of his study, published March 18 in Science Advances , have relevance for understanding key dates in Mediterranean history and prehistory, including the tomb of Tutankhamen and a controversial but important volcanic eruption on the Greek island of Santorini.