[AAS04-P09] Vertical characterization of PM2.5 based on observation using compact sensors on and around Mt. Unzen in Nagasaki Prefecture
Keywords:PM2.5, Transboundary Air Pollution , Compact sensor, Mountain
Aerosol particles in the atmosphere, including PM2.5, are known to have significant impacts on climate, the atmospheric environment, ecosystems, and human health. Whereas both of domestic sources and transboundary pollution from Asian Continent possibly contribute to the PM2.5 mass concentrations in Japan, high PM2.5 events owing to the transboundary pollution are often observed, especially in north-western part of Kyushu region (including Nagasaki Prefecture). Although PM2.5 mass concentrations are observed at the observatories of the Atmospheric Environmental Regional Observation System (AEROS) of the Ministry of the Environment, Japan (MOEJ), the observatory on mountain is very limited, and widely used large and expensive bate attenuation monitor (BAM) is not suitable for the multi-point observations.
We developed a compact PM2.5 sensor with Panasonic Corporation [Nakayama et al. 2018]. This sensor can measure PM2.5 mass concentrations by detecting light scattering intensities from individual aerosol particles with diameters greater than 0.3 µm. In this study, this sensor was applied for the observations of PM2.5 mass concentrations around Mt. Unzen in Nagasaki Prefecture from December 2018. The PM2.5 sensors were installed at six sites with different altitudes from 20 m to 1300 m to analyze vertical and horizontal distributions of PM2.5. During high PM2.5 events (>35 µg/m3) in winter, the PM2.5 mass concentrations at an altitude above 1000 m are similar to those at 20 m in most cases. However, in some cases, high PM2.5 was observed only at low altitude sites, likely because of inflow of clean air with lower aerosol burden from higher altitude to the mountain sites and/or low boundary layer height. The vertical profile data obtained in this work will be compared with the lidar data obtained by NIES at Omura city, which is located 38 km north-west of Mt. Unzen, to discuss the possible sources and transport patterns of PM2.5.
Acknowledgements
This work is supported by Unzen city, Shimabara city, Minamishimabara city, Unzen ropeway Corporation, and Eco Solutions Company, Panasonic Corporation.
Reference
T. Nakayama, Y. Matsumi, K. Kawahito, Y. Watabe, Development and evaluation of a palm-sized optical PM2.5 sensor, Aerosol Sci. Technol., 52, 2-12, doi:10.1080/02786826.2017.1375078 (2018).
We developed a compact PM2.5 sensor with Panasonic Corporation [Nakayama et al. 2018]. This sensor can measure PM2.5 mass concentrations by detecting light scattering intensities from individual aerosol particles with diameters greater than 0.3 µm. In this study, this sensor was applied for the observations of PM2.5 mass concentrations around Mt. Unzen in Nagasaki Prefecture from December 2018. The PM2.5 sensors were installed at six sites with different altitudes from 20 m to 1300 m to analyze vertical and horizontal distributions of PM2.5. During high PM2.5 events (>35 µg/m3) in winter, the PM2.5 mass concentrations at an altitude above 1000 m are similar to those at 20 m in most cases. However, in some cases, high PM2.5 was observed only at low altitude sites, likely because of inflow of clean air with lower aerosol burden from higher altitude to the mountain sites and/or low boundary layer height. The vertical profile data obtained in this work will be compared with the lidar data obtained by NIES at Omura city, which is located 38 km north-west of Mt. Unzen, to discuss the possible sources and transport patterns of PM2.5.
Acknowledgements
This work is supported by Unzen city, Shimabara city, Minamishimabara city, Unzen ropeway Corporation, and Eco Solutions Company, Panasonic Corporation.
Reference
T. Nakayama, Y. Matsumi, K. Kawahito, Y. Watabe, Development and evaluation of a palm-sized optical PM2.5 sensor, Aerosol Sci. Technol., 52, 2-12, doi:10.1080/02786826.2017.1375078 (2018).