Relationship between modern latitudinal TSI flux and sporomorph chemistry.
UAC data for Lycopodium spores (black circles and lines) and Pinus pollen19 (grey open circles and lines), plotted against modelled TSI32. Linear regression through both datasets show a significant positive relationship, for Lycopodium species y = 0.590 + 0.00115*TSI, n = 12, r2 = 0.36, p = 0.023, for Pinus y = −2537.51 + 28.84*TSI, n = 18, r2 = 0.62, p < 0.0001. Solid lines are fitted models, dashed lines are 95% confidence intervals. Ph/OH = phenolic/hydroxyl ratio from FTIR spectra of Lycopodium spores, p-CA = relative abundance of para-coumaric acid in Pinus pollen19.