Fig. 7

Prior distributions of ϕ and GDM, and the synthetic ¹⁴C data generated from the distributions. a and b Show the prior distributions of the solar activity and GDM, respectively. The grey lines depict 50 random realizations and the two black dashed lines indicate 2-sigma uncertainty of a thousand realizations. The orange lines represent the recent observations to which the model is connected, i.e., ϕ_HE16 and GDM based on COV-OBS. × 2. The blue lines represent the selected realization used to generate the synthetic ¹⁴C production rate. c Shows the synthetic ¹⁴C production rate (blue line) and the resampled values with 6.7% standard error (orange circles with error bars)