Fig. 3: Model calibration and validation.

Scatter-plot of the regression model (black line, Eq. (1) and red line of identity) vs. actual rainfall erosivity estimated upon the Po River landscape over the period 1993–2015, with the inner bounds showing 95% confidence limits (power pink coloured area), and the outer bounds showing 90% prediction limits for new observations (light pink) (A). Residuals between actual and modelled erosivity at the calibration stage (B). Time co-evolution (1981–1992) of actual (black curve) and estimated (red curve) of rainfall erosivity at validation stage (C).