Derryvree’s Tundra Sedgebeds
Radiocarbon results are not calendar dates in themselves. They must be calibrated against independently constructed curves that allow for past variation in atmospheric carbon-14. The modern IntCal20 curve extends to 55,000 calibrated years before present, with “present” conventionally fixed at 1950. Even then, a measurement is expressed as a probability range, often hundreds or more years wide. The further back one goes, the less defensible it is to translate a numbered BCE year into a precisely observed moment. Around 31,860 BCE, therefore, the proper historical unit is a dated environmental interval.