Abstract
To evaluate ambient particulate sulfate concentrations over a wide region, aerosol samples were collected at nine sites in the Kyushu-Okinawa district between 1 and 11 October 1991.
Particulate sulfate concentration in the Kyushu-Okinawa district was shown to be approximately similar in spatial distribution and daily variation among the sites studied. The concentration of particulate sulfate at Okinawa, located in an unpolluted southern marine area, was 7.7 μg/m3. This level is considered to be relatively high. The daily variations of particulate sulfate in the northern Kyushu region (Nagasaka, Saga, Dazaifu) were similar among the sites. The maximum concentration of particulate sultate in Okinawa was found to be delayed one day from that observed in Kagashima. Particulate sulfate in Okinawa was presumed to be transported from southern Kyushu.
High concentrations of elemental carbon were observed in urban areas, such as Kitakyushu and Kumamoto. Particulate clemental carbon in the kyushu-Okinawa district was shown to differ significantly in spatial distributions and temporal variations among sites.
