[COBOL2Java]

...a time schedule that will eventually be continuous all the way back, but that will vary from one region to another because climate varies from one region to another

IIRC, that is the weakness of dendrochronology. If you do not have a means of connecting tree rings regionally, then you lose the continuum. The statistical confidence level drops and you can't piece together a reliable timeline.

[RightWhale]

That is what I was thinking. The collection for the Upper Adriatic would have to be separate from that for Tunisia. There would be gaps in each collection, and making the various collections would involve a lot of serious fieldwork. Not a small project.