The Selection and Analysis of Related Factors for Ozone Episodes over Yulin-ChiaYi-Tainan Air-Quality Basin

Abstract

In these years, the pollution of ozone becomes worse in Yunlin, Chiayi, Tainan (Y-C-T) area in Taiwan. This study used multivariate statistical analysis and trajectory photochemical air quality model to analyze the database of air quality from 1999 to 2009. The goal of this study is to understand the pollution magnitude produced by sources of pollution, and provided the basis for control of ozone. This study investigated that the change on spatial and temporal variations of (Y-C-T) area. The result indicated that the NOx and NMHC had decreased in 1999 to 2009, but the ozone pollution was still worse in fall.Tainan station due to the direction of the monsoon that cause more of ozone hour station days. Factor scores above 2.5 is a useful index for selection of ozone episodes. Compare with non-ozone episodes, the result indicated that the highest concentration of ozone was produced by source of pollution when the climate was not conductive to diffuse. For decrease the magnitude of ozone, ozone precursors should be controlled. This study applied three statistical methods including correlation analysis, factor analysis, cluster analysis to investigate similarities of pollutant levels for monitoring stations and area classification in (Y-C-T) area,and investigated characteristics of those seprational regions.