A comparative Mineralogy of airborne dusts in Korea and Japan

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A co-research was conducted between Japan and Korea to investigate the origin of acid rain and global green house effect caused by atmospheric pollution. Emphases were placed on the characteristics of polluted atmospheric dust and long range transport of air dust by northwest winter monsoon. Air dust samples and acid deposits were collected from Seoul city, Korea and Kanazawa city, Japan to make comparable investigation and to evaluate the atmospheric pollution between two cities.Measurement of NO_2 and analysis by SEM with EDAX were carried out to survey the concentration of NO_2 and the characteristics of air dust and acid deposits both in two cities. NO_2 concentration over Seoul city ranges from 0.0285 ppm to 0.0845 ppm, suggesting a highly polluted air over Seoul city, which may be mainly caused by waste gases drainaged by automobiles. The result by SEM with EDAX analysis shows that air dust collected from Seoul area are composed of, not only soil particles such as clay minerals, … More but also considerable quantity of particles containing sulfuric materials and heavy metals such as Mn, suggesting a presence of anthropogenic polluted sources. Particularly, much porous spherical dust containing S and Ca were observed with SEM which are considered as residual materials from combustion of fossil fuel. Acid deposits (hails) collected from Kanazawa also show considerable amounts of small spherical dust containing S and Ca as main compositions. From spherical morphology of the particles different completely from normally occurred long columnar and needle crystals with an origin of volcanic eruption, we can infer that these spherical particles containing S and Ca may have an anthropogenic origin caused mainly by industrial activities. Above acid particles with sulfur of sulfate are easy to be condensed as colud nuclei, which is one of the origin resulting in acid rain. It is necessary to consider the global cycles and transport of anthropogenic air pollution and to investigate the pollution sources in wider area. Less