Mode and Place of Origin of Carbonaceous Aerosols Transported From East Asia to Cape Hedo, Okinawa, Japan

Abstract

This study investigated the source categories and emission areas of carbonaceous aerosols transported from East Asia to the East China Sea. Mass concentrations of heavy metals, ionic components, organic carbon, and elemental carbon (EC) were measured at the Cape Hedo Atmosphere and Aerosol Monitoring Station in Okinawa, Japan, throughout 2010. The relative influences of different categories of aerosols were determined by positive matrix factorization, and the source regions of each emissions category were evaluated by using the total potential source contribution function. Five source categories were identified: dust, sea salt and nitrate, secondary species, coal combustion, and oil combustion. The results showed that the major source of aerosols in North China is coal combustion, whereas the major source in South China, Japan, and Korea is oil combustion. The relative contributions of the five sources to EC concentrations at Cape Hedo were dust 7.0%, sea salt and nitrate 19.1%, secondary species 28.5%, oil combustion 12.8%, and coal combustion 32.6%. In particular, wintertime coal combustion in residential areas of North China contributed significantly to EC in 2010. The results also indicate that the contribution of coal combustion in source areas was higher in winter (52%), whereas the contribution of oil combustion was higher in spring (33%).

Measurement of Ambient PAHs in Kumamoto: Differentiating Local and Transboundary Air Pollution

“…By contrast, the seasonal variation in elements from coal combustion in Kumamoto was high in spring and winter and low in summer and autumn. This result is consistent with that in CHAAMS (Shimada et al, 2015). This indicates that the seasonal variation in metals from coal combustion is affected by transboundary pollution.…”

“…In addition, data of the site on Tuoji Island in China, which were obtained simultaneously with our experiments through collaborative research, were included in the PMF to determine the effect of TAP. The CHAAMS, Fukue, Fukuoka, and Tuoji sites have been described in detail by Shimada et al (2015), Sato et al (2013), andZhang et al (2016). The sampling method for PM 2.5 and analytical method for PM 2.5 and metals were reported by Shimada et al (2015).…”

“…The CHAAMS, Fukue, Fukuoka, and Tuoji sites have been described in detail by Shimada et al (2015), Sato et al (2013), andZhang et al (2016). The sampling method for PM 2.5 and analytical method for PM 2.5 and metals were reported by Shimada et al (2015). The error fraction was set to 0.15.…”

Model Estimation of Sulfate Aerosol Sources Collected at Cape Hedo during an Intensive Campaign in October-November, 2015

“…CHAAMS is located in northern Okinawa (26.87°N, 128.25°E, 60 m above sea level), far from Naha City, which is the largest city on Okinawa. The location of CHAAMS is suitable for capturing the atmospheric pollutants via LRT, and has already revealed the behavior of aerosols affected by the LRT Takiguchi et al, 2008;Hatakeyama et al, 2011;Shimada et al, 2015). During the intensive observation ), which is mainly produced by the oxidation of sulfur dioxide (SO 2 ), was the dominant aerosol component at CHAAMS (Tatsuta et al, 2017).…”

Contributions of Long-Range Transported and Locally Emitted Nitrate in Size-Segregated Aerosols in Japan at Kyushu and Okinawa

“…The threshold Pb concentration of 10 ng m -3 is the average concentration at Fukue Island, in the East China Sea just west of Kyushu, in spring and winter when long-range transport is dominant (Suzuki et al, 2014). Frequently in spring and winter, the air at HD, Fukue Island, and Fukuoka city is dominated by air masses transported from East Asia (Suzuki et al, 2014;Shimada et al, 2015). Sometimes such air masses pass over large cities in Kyushu such as Kumamoto and Fukuoka before arriving at HD (Taniguchi et al, 2017).…”