INFLUENCE OF THE GROWTH-MECHANISM OF SNOW PARTICLES ON THEIR CHEMICAL-COMPOSITION

Case studies of chemical analysis of solid precipitation were made at sites on the outskirts and central part of Sapporo City, Japan to inve stigate the difference in precipitation chemistry owing to the mechani sm by which snow particles grow, i.e. by vapor deposition or by riming . Even in vapor depositional growth, the samples were found to be acid ic. NO3- and nss-Cl- contributed to the acidification. In the samples of riming growth, the nss-SO42- concentration was considerably high. S now samples from the site in the central city area were less acidic du e to the higher concentration of nss-Ca2+ in the early period of snowf alls.