Simultaneous measurements of particulate elemental carbon on the ground observation network over the western North Pacific during the ACE‐Asia campaign

Abstract

The measurements of atmospheric aerosol and associated species have been carried out on the ground observation network over the western North Pacific as part of the Variability of Marine Aerosol Properties (VMAP) project. The network consists of four Japanese islands (Rishiri, Sado, Hachijo, and Chichi‐jima), ranging widely in latitudes from 25°N to 45°N along with the line of 140°E. In this paper, we report on simultaneous measurements of particulate elemental carbon (EC) on the four islands from March to May 2001, which cooperated with the Asia‐Pacific Regional Aerosol Characterization Experiment (ACE‐Asia) campaign, in order to characterize the outflow patterns of continental polluted air masses to the North Pacific. The mean concentrations of particulate EC in the four islands during this period ranged from 0.18 to 0.60 μg m−3. It is interesting to note that the temporal variations in the concentrations of particulate EC in Rishiri and Sado, which are located in the northern region of Japan (35°N–45°N), synchronized with each other. The EC concentrations in Hachijo and Chichi‐jima, located in the southern region of Japan (25°N–35°N), also showed similar temporal variations with each other but did not synchronize with those in Rishiri and Sado. These results demonstrate that the transport patterns of the polluted air masses from the east Asian continent to the northern regions of the northwestern Pacific are often different from those to the southern regions. It was also found that continental air masses are usually accompanied by pollutants over the southern regions but not over the northern regions of the northwestern Pacific.

Long-term observation of trace metal concentration in aerosols at a remote island, Rishiri, Japan by using inductively coupled plasma mass spectrometry equipped with laser ablation

“…The obtained trace metal concentration levels in the aerosol were almost of the same as those obtained previously at Oki Island, Japan (Mukai et al, 1990), 1/10-1/70 of those obtained at Beijing, China (Okuda et al, 2004), and 1/2-1/40 of those obtained at Tokyo, Japan (Mizohata et al, 2000). Moreover, the concentration levels of the obtained watersoluble ionic constituents in the aerosol corresponded almost entirely to previous observation results for Rishiri Island from March to May 2001 (Matsumoto et al, 2003).…”

“…Rishiri is close to Siberia; it is 50 km from Sakhalin and 800 km from Vladivostok, Russia. Previous studies performed on Rishiri Island (Matsumoto et al, 2003) and Okushiri Island, which is located about 370 km southwest of Rishiri Island (Rahn et al, 1989), were focused on sector analysis of the inflow of air pollutants from Russia, China, and the Japanese mainland. Based on the previous studies, we classified the area surrounding Rishiri Island geographically into four sectors "Marine", "Japan", "China", and "Siberia" for our sector analysis (Figure 3).…”

Organic carbon and elemental carbon associated with PM10 in Beijing during spring time

“…The amounts of carbonaceous substances evolved at 280 and 340 • C were defined as organic carbon (OC) and 750 • C as total carbon (TC), and the difference between the two is the EC. Detailed description of this instrument has been given in the previous studies [31,[34][35][36]. Meanwhile R&P 5400 has a high resolution of 0.25 g m −3 and it was calibrated by Beijing Branch of Rupprecht & Patashnick Co. Inc. before it was deployed.…”

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

“…3(d), 3(e), and 5). On the basis of simultaneous observations at remote sites, Matsumoto et al (2003) reported that the transport patterns of polluted air masses moving from East Asia to the northern Northwest Pacific are often different from those moving to the southern Northwest Pacific. In addition, the number of low-and high-pressure systems moving eastward from South China increases in spring (Uno et al, 2000;Hatakeyama et al, 2001;Shimada et al, 2011).…”