AbstractSnowmelt runoff has major influence on water supply and hazards for many temperate and polar regions. The magnitude and timing of runoff depend on the processes of snow accumulation and melt, which are controlled by factors that include latitude, topography, and land use. The amount of runoff production is affected by meltwater loss to evaporation and infiltration, the latter is often limited by frozen soil conditions. Runoff is delivered as flow in the snow, overland flow on bare ground, channeled flow in rills and interhummock cracks, or as subsurface flow in organic soils. The flow may be modified by the presence of snow or river ice in the channels, which often causes runoff delay and amplification of peak flows. Streamflow hydrographs for small basins typically show diurnal cycles with high discharge during warm days and declines in the cool and terminating periods of snowmelt. Hydrographs of large basins are an integration of the runoff patterns of their subbasins. In terms of snow management, the control of snowmelt floods is a consideration, yet many arid regions look to snowmelt runoff as a source of water supply.
