Field work was carried out to investigate the regional characteristics of the concentration of major chemical constituents of snow cover from the coastal area of the Japan Sea to the mountain ranges of central Japan during the winter (January) of 1985. The snow cover in the interior highlands, such as Sugadaira and Takamine, was dry, and therefore the total snow cover retained the concentration of chemical constituents in the snow fall there. In contrast, in the Takada plain, a heavily snow-covered plain of the coastal area in Japan, the lower part held granular snow which contained melt water, and only the upper new snow layers retained the condition of accumulation of chemical constituents. The ratios of concentration of each of the chemical constituents in the new snow suggested that the Na+, Mg2+, and Cl- originated from sea water. The spatial distribution of the concentration of eash chemical constituent in the new snow which accumulated during one series of snowfalls under a winter monsoon situation was claritied. The concentration of chemical constituents originating in sea water decreased farther inland. This distribution was related not only to the distance from the coast but also to topography and the regional differences in cumulus development due to the topography. Excess Ca2+ and SO42- from the expected value originating in sea water were found. In particular, the distribution of excess Ca2+ showed strong regional characteristic, which suggested that there was another source of Ca2+ besides the sea water in the inland areas. Meanwhile, most of the samples contain excess SO42-, which decreases with decreasing amounts of accumulated new snow. The spatial distribution of NO3- concentration in the new snow cover in Sugadaira showed a large variation. The results suggested that the source of the nitrogen oxide was in the neighborhood of the sampling points.
Translatory flow is observed in a ground water runoff during a rainstorm. Layered snow cover is considered to play the same role as soil layer for water runoff. The purpose of this paper is to report the translatory flow phenomena of snow meltwater in a snowpack. Studies on the snowmelt runoff in a snowpack were carried out at eastern Canada and Hokkaido. In the case of Canada, the hydrograph of snowmelt is separated into “old water” (meltwater in the lower snowpack) and “new water” (meltwater percolated from surface snow layer) by the concentration of NO3-. The concentration of NO 3- in meltwater in the lower snowpack is estimated to be higher than that in meltwater generated from the surface snow layer. Separated “old water” is the major component of early snowmelt runoff during a day. This quick response of the meltwater in the lower snowpack requires a translatory flow mechanism in the snowpack. “New water” is the major component of the recession limb of the hydrograph. The same phenomena were observed at Moshiri, Hokkaido, during the 1988 snowmelt. Two peaks on the meltwater hydrograph were observed. The first peak is composed of the meltwater in the lower snowpack; the major component of the second peak is the meltwater percolated from the surface snow layer. The translatory phenomenon in a snowpack is not observed when the depth of snow cover is not so thick.