“…During dye tracer experiments in a nonripe snowpack with temperatures below the freezing point, matrix flow was observed in the uppermost layers of the snowpack whereas preferential flow was observed in deeper layers only (Techel et al, 2008;Würzer et al, 2017). Various approaches of water flow transport in snowpack were further investigated which included rainfall simulation (Conway and Benedict, 1994;Eiriksson et al, 2013;Juras et al, 2013;Singh et al, 1997), artificial wetting (Avanzi et al, 2015;Katsushima et al, 2013; and numerical modelling (Hirashima et al, 2010(Hirashima et al, , 2014Wever et al, 2014aWever et al, , 2015. Rainwater can refreeze when percolating through cold snow (Pfeffer and Humprey, 1998).…”