1996 Volume 58 Issue 4 Pages 285-294
The chemical composition of snowfalls in the Teshio Experimental Forest Hokkaido University in northern Hokkaido was investigated from December 1990 to March 1995. Although there was no industrial source of acid pollutants around the study area, most of the snowfalls observed were “acid snow”. with pH valnes less than 5.6. The pH values of snofalls after cyclones were lower than those before cyclones. Snow were brought from W in the Japan Sea side and from N in the Okhotsk Sea side, the former is important to monitor acid pollutants which are likely to be transported from the Chinese mainland.
Although non-seasalt SO42- was relatively rich in the snowfalls in the Japan Sea side, there was no difference in pH of snowfalls with different wind directions. The presence of non-seasalt Ca2+in the Japan Sea side snowfalls suggested that the acidity of snowfalls was partly neutralized by the soil particles in the air, such as loess particles, covering over the Continent.
