著者
Koichi Watanabe Hirohito Satoh Teruya Maki
出版者
Meteorological Society of Japan
雑誌
SOLA (ISSN:13496476)
巻号頁・発行日
pp.2022-017, (Released:2022-04-12)
被引用文献数
1

The number concentrations of microbial (counted as viable) particles and size-separated particles were measured continuously in Imizu City, Toyama, in the coastal region of the Sea of Japan, in 2015 using a commercial real time viable particle counter. From February to June, large increases in the number concentrations of coarse particles with rapid increases of viable particles were observed during Asian dust events. In mid-July, a phenomenon was observed in which the number concentrations of viable particles decreased, although coarse particles significantly increased. From the results of the backward trajectory analysis, the phenomenon was considered to be due to the transport of volcanic ash from Nishinoshima. The monthly average number concentrations of the viable particles were highest in September, whereas the average concentrations of coarse particles were at a maximum in April.
著者
Koichi Watanabe Liu Yang Satoru Nakamura Takuya Otani Kenzaburo Mori
出版者
Meteorological Society of Japan
雑誌
SOLA (ISSN:13496476)
巻号頁・発行日
vol.17, pp.109-112, 2021 (Released:2021-05-22)
参考文献数
18
被引用文献数
3

Aerosol number concentrations and trace gases (SO2, O3, HCHO, and H2O2) were measured over Imizu City, Toyama Prefecture, Japan on 5 August 2020, from a helicopter. The concentrations of fine particles (0.3-0.5 μm) were high at ground level and at an altitude of approximately 1200 m due to the volcanic plume from Nishinoshima. However, concentrations of aerosol particles were low at an altitude of approximately 2400 m. The volcanic plume did not significantly affect the lower free troposphere. High concentrations of SO2 were also observed. The H2O2 concentrations (0.27-0.56 ppb) were much lower than those during previous observations in the summer (2.0-6.7 ppb) and significantly lower than the SO2 concentrations (1.8-3.3 ppb). The concentrations of HCHO (2.1-2.5 ppb) were higher than those of H2O2. The oxidation of S(IV) to H2SO4 in cloud water might have been suppressed over the studied area.
著者
Koichi Watanabe Liu Yang Satoru Nakamura Takuya Otani Kenzaburo Mori
出版者
Meteorological Society of Japan
雑誌
SOLA (ISSN:13496476)
巻号頁・発行日
pp.2021-017, (Released:2021-04-21)
被引用文献数
3

Aerosol number concentrations and trace gases (SO2, O3, HCHO, and H2O2) were measured over Imizu City, Toyama Prefecture, Japan on August 5, 2020, from a helicopter. The concentrations of fine particles (0.3-0.5 μm) were high at ground level and at an altitude of approximately 1200 m due to the volcanic plume from Nishinoshima. However, concentrations of aerosol particles were low at an altitude of approximately 2400 m. The volcanic plume did not significantly affect the lower free troposphere. High concentrations of SO2 were also observed. The H2O2 concentrations (0.27-0.56 ppb) were much lower than those during previous observations in the summer (2.0-6.7 ppb) and significantly lower than the SO2 concentrations (1.8-3.3 ppb). The concentrations of HCHO (2.1-2.5 ppb) were higher than those of H2O2. The oxidation of S(IV) to H2SO4 in cloud water might have been suppressed over the studied area.
著者
渡邊 光一 Koichi WATANABE
巻号頁・発行日
no.3, pp.A167-A180, 1996-12-20