Fig. 4: Spatial contribution of melt to catchment inputs.

a to c The stream network (blue river network) shaded to represent specific discharge (scale limited to 0.001 m³ s⁻¹/m²). The pie charts show the proportional contribution of rain (blue), snow melt (cerise) and ice melt (orange) to liquid water inputs (before accounting for evapotranspiration or infiltration) within the section of the catchment they are next to (outlined in grey) and all sections upstream on the same side (the catchment was split into 10 km sections and then by east and west sides). Glacier areas (light blue) are from ref. ⁶⁶, with the gauged catchments shown in black, with the outlet points yellow dots. The letters correspond to the panels in Fig. 3. d to f The fractional contribution of the inputs in relation to distance to the outlet, with blue lines for rain, cerise lines for snow melt and orange lines for ice melt, lines with no markers represent the Negra (west) side of the catchment, and lines with dot markers represent the Blanca (east) side. The seasonal contributions are calculated here as the mean of the month values in each season. All values are based on model outputs averaged over the 2008–2018 analysis period.