2000 years of drought variability in Europe

The animation shows rolling standard deviation for an 11 year window (evaluated at its 6th year midpoint).

Source: Cook, E.R., Seager, R., Kushnir, Y., Briffa, K.R., Büntgen, U., Frank, D., Krusic, P.J., Tegel, W., van der Schrier, G., Andreu-Hayles, L. and Baillie, M., 2015. Old World megadroughts and pluvials during the Common Era. Science advances, 1(10), p.e1500561.