Abstract
Timing and intensity of melt water, which is closely related to the landslide occurrence, was measured using snow lysimeters and other meteorological observations including snow depth and water equivalent of snow in a landslide area of a heavy snow district. Results of four winter seasons' (1989 to 1992) observation showed that rain on snow events frequently occurred early in the season. During snowmelt season, melt water was mainly generated in the surface layer of snow cover by solar radiation and high air temperature. Therefore, most melt water was produced during the daytime of almost every day. In years with small snowpacks, melt water was generated intermittently by occasional rainfall and higher temperatures even in January and February. It was estimated that quantity and intensity of the melt water would be highest in the later stage of the snowmelt season because a large amount of precipitaion was stored as a snow cover up until April and May for heavy snow years.
