抄録
Samples of water-soluble ionic species in size-separated aerosol particles, acidic gases and ammonia were collected at Murododaira (2450 m a.s.l.) and Daikanbou (2320 m a.s.l.) near Mt. Tateyama, Japan, during the winter to spring season. The field observations consist of 2 to 14 days in November through April of 1995 to 2000. Median concentrations of the water-soluble ions in the aerosol particles and gases in the spring were about 2 to 8 times higher than those in the winter. The concentrations of NH+4, nssK+, C2O2-4 and nssF- in fine (<2. 1 μm) particles showed good correlations with nssSO2-4, suggesting that nssSO2-4 observed at Mt. Tateyama originated from anthropogenic sources. The molar ratios of NH+4 /nssSO2-4 for the fine particles at Mt. Tateyama changed from about 1 in the winter to about 2 in the spring, suggesting that atmospheric sulfate aerosols were present as ammonium bisulfate in the winter and as ammonium sulfate in the spring.
