Extended Data Fig. 7: Statistically significant increases in dry and wet local deviation frequency, comparing 1931–1960 against 1691–1860.

Panels show increases in dry and wet local deviation frequency for streamflow (a), for soil moisture (b), and combined for streamflow and soil moisture (c). Changes in the frequency of local deviations are computed by comparing the ensemble median frequency of local deviations during 1931–1960 against 1691–1860, and significance of change is tested at a 95% confidence level (P = 0.05) with R package stats function prop.test⁹⁶ (one-sided test). Colours denoted with + indicate statistically significant increases with magnitude less than 5 pp (minor), whereas colours denoted with ++ indicate statistically significant increases with magnitude greater than 5 pp (major). Colours denoted with +(+) pool together any statistically significant increase (minor or major).