Fig. 1: Overview of the measured 14C data from tree rings.
From: Tracing ancient solar cycles with tree rings and radiocarbon in the first millennium BCE
a Individual measurement results in radiocarbon age before the year 1950 of each tree with 2-σ error bars. b Difference between the annual data and the IntCal20 calibration curve in 14C age. Error bars indicate the 2-σ error bars. The green line shows a Savitsky-Golay smoothed curve.
