The curve called INTCAL09, has just been published in the journal Radiocarbon. It not only extends radiocarbon calibration but also considerably improves earlier parts of the curve.
Dr Ron Reimer of the Queen’s School of Geography, Archaeology and Palaeoecology said: “The new radiocarbon calibration curve will be used worldwide by archaeologists and earth scientists to convert radiocarbon ages into a meaningful time scale comparable to historical dates or other estimates of calendar age.
“It is significant because this agreed calibration curve now extends over the entire normal range of radiocarbon dating, up to 50,000 years before today. Comparisons of the new curve to ice-core or other climate archives will provide information about changes in solar activity and ocean circulation.”
It has taken nearly 30 years for researchers to produce a calibration curve this far back in time.