suzuki_2003.htm

Bulletin of Glaciological Research 20 (2003) 15-20
©Japanese Society of Snow and Ice

Chemical property of snow meltwater in a snowy temperate area

Keisuke SUZUKI

Department of Environmental Sciences, Shinshu University, Matsumoto 390-8621 Japan

Abstract

　We studied the chemical properties of snow meltwater in a snowy temperate area, where air temperature above the freezing point and rainfall are observed even in mid-winter. The amount of bottom-melt beneath the snow cover in the snowy temperate area we studied was below 1 mm/day, which is similar to the amount in a snowy cold area. However, in the case of winter melting, the pH of the meltwater decreased and its electric conductivity increased correspondingly. As the snowmelt progressed, the oxygen-18 (d18O) of the snow cover increased gradually, and as a result, the d18O of the meltwater also increased accordingly. We conducted a multiple regression analysis with four species of acidifying ions (NO3- and nss-SO42-) and neutralizing ions (NH4+ and nss-Ca2+) in meltwater as independent variables and H+ as a dependent variable. We could explain 86% of the H+ concentration fluctuation in meltwater based on the concentrations of these four ion species. A clear diurnal variation is observed in anion concentrations in meltwater at the peak melt season. The anion enrichment factors in meltwater are higher in the order of NO3-, nss-SO42- and Cl-, with values of 7.7, 7.2 and 4.0, respectively.