Figure captions for Supplemental Figures:
Figure S1 (Supplemental Figure 1) U/Th dating constraints for the overlapping coral
18O sequences in Figure 4. a, A comparison of U/Th dates with the relative dating
constraints from the overlapping corals, the latter shown as “splice dates”, for samples
representing the three coral sequences shown in Figure 4a. One can evaluate the fit for
alternative “splice” dates by sliding the data points in this figure en masse horizontally
along the splice date axis. We estimate the error of our best fit splice dates at ±5yrs.
Lower error bars reflect analytical precision alone (2), while the upper error bar reflects
error in the correction for non-radiogenic thorium as well as analytical precision. b,
Same as a but for the five corals plotted in Figure 4b.
Figure S2 (Supplemental Figure 2) The standard deviation of 2-7y 18O variability vs.
mean coral 18O, as computed in sliding 30y windows of the Palmyra coral
reconstructions. The overall correlation coefficient (-0.43) is significant at the 90% level
(assuming 13 degrees of freedom, where N equals the total number of years of data
(440y) divided by the window length (30y)).