Analysis of PM_2.5 in Shiga Prefecture using an atmospheric chemistry transport model

Abstract

 Influences of transboundary air pollution and neighboring urban area sources are important for the environmental measures of PM_2.5. Research on PM_2.5 for Shiga Prefecture has been insufficient so far. Shiga prefecture has the various geographical features, for example, Lake Biwa, the basin and the mountains, and there are different characteristics from the Metropolitan area and remote isaland. In this study, PM_2.5 was observed at the northern and sourthern parts of Shiga prefecture and in Iga city in Mie prefecture separated from Shiga prefecture by mountains. Analyses of PM_2.5 concentration were carried out using the atmospheric chemistry transport model WRF/CMAQ. Good agreements between the WRF/CMAQ and the observation were obtained. In the winter season, transboundary air pollution caused similar daily variations of PM_2.5 concentration in the southern and northern parts of Shiga. In the summer season, the PM_2.5 concentrations increased in the sourthern part of Shiga prefecture and Iga city. These increases were due to the transport of air pollutants from the Kinki urban area.