Chemical survey of the snowpack in central Japan

In order to elucidate the spatial variation of chemicals deposited with snowfall in central Japan and the chemical characteristics of the snowpack in the mountainous area, samples from new surface snow and from snow pits were collected during the 2000-2001 winter season. There is a clear relationship between rising electric conductivity (EC) and falling pH for the new surface snow samples. The Na+ concentration correlates well with the Cl- and Mg2+ concentrations for new surface snow, suggesting that the contributions of sources other than sea salt are negligible. Thus, sea water is the predominant source of Na+, Cl-, and Mg2+ in new surface snow in central Japan. The ratio of Cl-/anions in new surface snow correlates well with latitude;there is a higher ratio of Cl-/anions at the sampling locations near the Sea of Japan. On the other hand, the ratio of NO3-/nssSO42- is high in the southern locations. The pH value for the snow pit samples is determined by the acid index. The colored layers deposited during the Kosa event are characterized by high EC, high pH, and high ion concentrations. The EC and Cl- concentration in new surface snow along roads are higher on the coastal plain than farther inland. On the other hand, the pH and ratio of NO3-/nssSO42- are lower on the coast than farther inland.