Japan Geoscience Union Meeting 2018

Presentation information

[EJ] Evening Poster

A (Atmospheric and Hydrospheric Sciences) » A-AS Atmospheric Sciences, Meteorology & Atmospheric Environment

[A-AS06] Atmospheric Chemistry

Wed. May 23, 2018 5:15 PM - 6:30 PM Poster Hall (International Exhibition Hall7, Makuhari Messe)

convener:Yoko Iwamoto(Graduate School of Biosphere Science, Hiroshima University), Tomoki Nakayama(Graduate School of Fisheries and Environmental Sciences, Nagasaki University), Sakae Toyoda(東京工業大学物質理工学院, 共同), Nawo Eguchi(Kyushu University)

[AAS06-P07] Using small compact PM2.5 sensors, long term and multipoint measurements in Hanoi, Vietnam

*OKAMOTO WATARU1, Yutaka Matsumi1, Kazuhiko Sekiguchi2, Takeshi Fujino2, Kenshi Sankoda2, Kimiyo Kumagai3, Yuji Fujitani4, Ly Bich Thuy'5, Nghiem Trung Dung5, Nguyen Thi Thu Thuy 6, Pham Chau Thuy7, Yoshizumi Kajii8, Yousuke Sakamoto8 (1.ISEE Nagoya University, 2.Saitama University, 3.Gunma Prefecture Sanitary Environment Laboratory, 4.National Institute for Environmental Studies, 5.Hanoi University of Science and Technology, 6.Thai Nguyen University of Technology , 7.Vietnam National University of Agriculture, 8.Kyoto University)

Keywords:PM2.5 measurement, compact sensor, air quality, Mega city, Southeast Asia

A year round observation of PM2.5 mass concentrations was conducted in Hanoi University of Science and Technology (HUST) from July 2016 to now using newly developed highly sensitive sensors. And also from October 2017 to now, we have installed the PM2.5 sensors in Thai Nguyen University of Technology (TNUT) and Vietnam National University of Agriculture (VNUA). Hourly PM2.5 concentration data in HUST agreed well with corresponding data obtained with a beta attenuation monitor, located 3 km away. The monthly variation showed that PM2.5 levels were high in the dry season, particularly in December (median = 62 mg m−3) and low in the rainy season, particularly in June and July (medians = 19 mg m−3). PM2.5 haze episodes with levels higher than 100 mg m−3 were observed 13 times during the dry season (October 2016–March 2017). These episodes may link to meteorological conditions, because the daily PM2.5 and CO levels increased several days after a cold surge for most of the PM2.5 haze episodes. Two episode events were investigated further in higher temporal resolution. For both events, PM2.5 peaks appeared at midnight for some days after a cold surge, while CO levels often increased at rush hours. For first event, short peaks of PM2.5 (duration of about 1 h) with fast rates of increase of ~5 mg m−3 min-1 were observed. This highlights the importance of high temporal resolution of PM2.5 sensors in assessing of health effect. For second event, a broad peak (duration of one and half days) of PM2.5 with gradual increase was observed together with high CO levels. This research reveals for first time characteristics of PM2.5 haze episode in Hanoi that should be studied further to develop an effective air pollution management in this city. This study is supported by JSPS Kakenhi (17H04483).