11:00 AM - 1:00 PM
[ACG43-P05] Development of a portable PM2.5 measurement system for cold regions and its deployment from the Hokuriku region to Northern Japan
Keywords:PM2.5, cold region, air pollution, observation, Instrument Development, wildfire
To assess the transboundary air pollution transport from the Eurasian continent, such as Siberian wildfire smoke (e.g., Yasunari et al., 2018, https://doi.org/10.1038/s41598-018-24335-w), we recently installed the latest PM2.5 measurement systems in Hakodate (Hokkaido; https://www.arc.hokudai.ac.jp/en/210421-1/), Hirosaki (Aomori; https://www.arc.hokudai.ac.jp/en/210702-1/), and Nagaoka (Niigata; https://www.arc.hokudai.ac.jp/en/211104-1/). We started the observations in 2021 from April 19, June 28, and November 1, respectively. In this presentation, we introduce the time-series data of each observation, comparing them to the nearby station data by the Ministry of Environment from the AEROS website (called Soramame-Kun in Japanese; https://soramame.env.go.jp/). We used the calculated hourly mean data from the measurements at the three sites. We compared them to the nearby AEROS station data (Chubu Elementary School in Hakodate, Bunkyou Elementary School in Hirosaki, and Sirooka-Jihai in Nagaoka). The AEROS station in Hakodate is an ambient air quality monitoring station, and the others in Hirosaki and Nagaoka are roadside monitoring stations. We calculated the number of the most frequently available data per hour for the data periods. On the calculated hourly mean data, we used the mean data for further analyses only when the number of data per hour was greater than 90% of the most frequent value. We used half an hour for plotting, but we also excluded data when the calculated center time of the hour in the hourly mean data by more than one minute due to possible other data biases. On comparisons between our observations and the AEROS data, the highest correlations were found in Hakodate as a case of comparisons with the ambient air quality monitoring station. For example, in Hakodate, on May 8-9, the PM2.5 mass concentrations were highly increased (greater than 50 μg m-3), corresponding to the Asian dust transport from the Gobi desert. In Hirosaki, the AEROS station frequently showed a higher PM2.5 background level. However, our data observed at the rooftop of the Faculty of Science and Technology, Hirosaki University, showed relatively clean background conditions. Although the data covering period is still short in Nagaoka, our data and the AEROS data perhaps capture the large timely variations of PM2.5. However, our data showed a relatively clean PM2.5 background. We introduce more characteristics of the PM2.5 variations on the presentation day at each observation site.