Though limited in extent, seasonal snowpacks in the Earth's mountain ranges account for the major source of the runoff for stream flow and groundwater recharge over wide areas of the mid‐latitudes. In most alpine regions, snowmelt runoff is responsible for the annual maximum instantaneous discharge and most of the annual flow. It is therefore important to understand the processes controlling snowmelt runoff and its chemical composition for both water resources as well as ecological reasons. Progress in snow hydrology over the past quadrennium has been heavily influenced by the availability and anticipated future availability of remote sensing data at times and spatial scales appropriate for addressing local, regional and global hydrologic issues [Dozier, 1992]. Recent research has examined topics contributing to better estimation of snowpack properties, snow distribution, snowmelt, and related chemical and biological questions. This review focuses mainly on seasonally snow‐covered alpine areas, but includes other research potentially applicable to alpine areas of the Earth. Copyright 1995 by the American Geophysical Union.