Using Tree Rings to Determine the Start of the Medieval Dark Ages

The science of dendrochronology observes changes in the pattern of tree rings in an attempt to create a time line and infer climate changes. Using tree ring data, it is possible to link the past 11,000 years in parts of Germany & Northern Ireland, but only the past few centuries in other parts of the world. » 2/10/12 7:00am 2/10/12 7:00am