Asian dust storms invaded Taiwan in springtime. During the Asian dust-storm periods, the dust particles suspended in the atmosphere could not only deteriorate the ambient air quality, mainly high particulate matter concentration and low visibility, but also cause severely adverse effects on human health. In this study, Asian dusts were sampled at Pencadores Islands and characterized the physical and chemical characteristics to investigate the influence of Asian dust storms. Due to its clean atmosphere, Pencadores Islands can be treated as one of the best air quality background sites in Taiwan.
In this sampling campaign, five Asian dust storm episodes were observed at Pencadores Islands. Asian dusts transported to Taiwan along the east of China or the east ocean of China and invaded Taiwan from either the northeast or the northwest. The concentrations of atmospheric aerosols during Asian dust storm episodes were 2-3 times higher than the background level. The concentration of PM10 increased dramatically. The increase of PM10 concentration was mainly attributed to coarse particles. The ratio of coarse particles to fine particles for Asian dust storm periods was higher than those for non-Asian dust storm periods.
From March to April, the concentration of PM10 increased due to sea-salt aerosol blow into atmosphere by strong eastwest monsoon. It suggested that, at Pencadores Islands, seawater was major chemical species of suspended particles. The concentration of F-, Cl-, Br-, NO3-, SO42-, Na+, Mg2+, and Ca2+ increased during Asian dust storm episodes indicated that pollutant would be transport by Asian dusts. The most possible chemical species in coarse particles would be MgSO4 and CaSO4.
The carbon content of suspended particles increased dramatically. The increase of carbon content of coarse particles was mainly attributed to elemental carbon. The increase of carbon content of fine particles was mainly attributed to organic carbon from second reaction. The concentration of Al, K, Br-, Fe, and Ca increased during Asian dust storm episodes indicated that Asian dust storm would transport dusts to Pencadores Islands.
The major pollution sources were mobile sources and dust sources at Pencadores Islands. During the Asian dust-storm periods, the percentages of industrial sources, seawater, and secondary aerosols increased dramatically.
| Identifer | oai:union.ndltd.org:NSYSU/oai:NSYSU:etd-0910103-134336 |
| Date | 10 September 2003 |
| Creators | Tsung, Shao-Cheng |
| Contributors | none, none, none, none |
| Publisher | NSYSU |
| Source Sets | NSYSU Electronic Thesis and Dissertation Archive |
| Language | Cholon |
| Detected Language | English |
| Type | text |
| Format | application/pdf |
| Source | http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0910103-134336 |
| Rights | campus_withheld, Copyright information available at source archive |
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