著者
Katsuya Yamashita Satoru Yamaguchi Takayuki Saito Yuya Yamakura Eiichiro Kanda Sento Nakai Hiroki Motoyoshi
出版者
Meteorological Society of Japan
雑誌
SOLA (ISSN:13496476)
巻号頁・発行日
pp.2020-045, (Released:2020-11-23)

A system with existing snowfall sensors, which is used to control the operation of the sprinkler snow removal system, was developed to acquire data that can be used to generate snowfall distribution with high spatiotemporal resolution. This had advantages such as low installation and management costs, as well as flexibility with respect to the configuration of its observation points. The results confirmed that this system, developed for experimental purposes in Nagaoka City (Niigata Prefecture), made it possible to generate the snowfall amount distribution as well as the precipitation rate within a 25 km × 30 km area at 10-min intervals based on in-situ measurements conducted at 16 ground-based points. A comparison of the system with other observation systems confirmed that it could detect detailed spatial snowfall variations, which could not be achieved using existing the ground-based observation networks, and provide sufficient observation accuracy for winter road management. Since many snowfall sensors are installed on the Sea of Japan side of mainland of Japan, this system has the potential for extensive application in the snowy areas of Japan characterized by heavy snowfall at temperatures of approximately 0°C.
著者
Narihiro Orikasa Atsushi Saito Katsuya Yamashita Takuya Tajiri Yuji Zaizen Tzu-Hsien Kuo Wei-Chen Kuo Masataka Murakami
出版者
Meteorological Society of Japan
雑誌
SOLA (ISSN:13496476)
巻号頁・発行日
vol.16, pp.212-219, 2020 (Released:2020-11-05)
参考文献数
31
被引用文献数
2

Since March 2012, multi-year ground-based observation of atmospheric aerosol particles has been carried out in Tsukuba, Japan to characterize the aerosol particle number concentrations (NCs), air mass origin relevance, and specifically, their cloud condensation nuclei (CCN) and ice nucleating particle (INP) characteristics. The CCN NCs at any water supersaturation (SS) exhibit strong seasonality, being higher in winter and lower in summer; this pattern is similar in the polluted urban environment in East Asia and contrary to that in the Pacific coastal region. The hygroscopicity (κ) is generally high in early autumn and low in early summer, likely due to the seasonal difference of synoptic-scale systems. In contrast, the INP NCs and ice nucleation active surface site density (ns) at defined temperature (−15 to −35°C) and SS (0%-5%) lack clear seasonal influence. The average INP NCs and ns in this study were comparable at warmer temperatures and approximately one order of magnitude lower at colder temperatures, compared with those in other urban locations under limited dust impact. Moreover, the ns values were one to four orders of magnitude lower and exhibited weaker temperature dependence than previous parameterizations on mineral dust particles.
著者
Katsuya Yamashita Satoru Yamaguchi Takayuki Saito Yuya Yamakura Eiichiro Kanda Sento Nakai Hiroki Motoyoshi
出版者
Meteorological Society of Japan
雑誌
SOLA (ISSN:13496476)
巻号頁・発行日
vol.16, pp.271-276, 2020 (Released:2020-12-26)
参考文献数
16

A system with existing snowfall sensors, which is used to control the operation of the sprinkler snow removal system, was developed to acquire data that can be used to generate snowfall distribution with high spatiotemporal resolution. This had advantages such as low installation and management costs, as well as flexibility with respect to the configuration of its observation points. The results confirmed that this system, developed for experimental purposes in Nagaoka City (Niigata Prefecture), made it possible to generate the snowfall amount distribution as well as the precipitation rate within a 25 km × 30 km area at 10-min intervals based on in-situ measurements conducted at 16 ground-based points. A comparison of the system with other observation systems confirmed that it could detect detailed spatial snowfall variations, which could not be achieved using existing the ground-based observation networks, and provide sufficient observation accuracy for winter road management. Since many snowfall sensors are installed on the Sea of Japan side of mainland of Japan, this system has the potential for extensive application in the snowy areas of Japan characterized by heavy snowfall at temperatures of approximately 0°C.
著者
Narihiro Orikasa Atsushi Saito Katsuya Yamashita Takuya Tajiri Yuji Zaizen Tzu-Hsien Kuo Wei-Chen Kuo Masataka Murakami
出版者
Meteorological Society of Japan
雑誌
SOLA (ISSN:13496476)
巻号頁・発行日
pp.2020-036, (Released:2020-09-23)
被引用文献数
2

Since March 2012, multi-year ground-based observation of atmospheric aerosol particles has been carried out in Tsukuba, Japan to characterize the aerosol particle number concentrations (NCs), air mass origin relevance, and specifically, their cloud condensation nuclei (CCN) and ice nucleating particle (INP) characteristics. The CCN NCs at any water supersaturation (SS) exhibit strong seasonality, being higher in winter and lower in summer; this pattern is similar in the polluted urban environment in East Asia and contrary to that in the Pacific coastal region. The hygroscopicity (κ) is generally high in early autumn and low in early summer, likely due to the seasonal difference of synoptic-scale systems. In contrast, the INP NCs and ice nucleation active surface site density (ns) at defined temperature (−15 to −35°C) and SS (0%-5%) lack clear seasonal influence. The average INP NCs and ns in this study were comparable at warmer temperatures and approximately one order of magnitude lower at colder temperatures, compared with those in other urban locations under limited dust impact. Moreover, the ns values were one to four orders of magnitude lower and exhibited weaker temperature dependence than previous parameterizations on mineral dust particles.