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• Main Authors: Jung-Shu Chang, 張榕書
• Other Authors: Kuo-Ying Wang
• Format: Others
• Language: zh-TW
• Published: 2006
• Online Access: http://ndltd.ncl.edu.tw/handle/3jyj8h

碩士 === 國立中央大學 === 大氣物理研究所 === 94 === Long-term (Mar 1994-Feb 2005) near-surface ozone data from 72 sites have been analyzed to present the seasonal distribution and trends of ozone in Taiwan. In the data quality check, there are the systemic loss of data in some hours of day. The distribution and trends of seasonal ozone concentration are discussed by four classifications: (1) monthly mean; (2) monthly day-time( 08:00-20:00 ) average ; (3) monthly average of daily maxima; (4) maximum of month. The distribution of seasonal ozone concentration of monthly mean and monthly day-time average is similar. The distribution of maximum of month indicates summer maximum in Xin-Dian site. Comparison between average of seasonal ozone of entire Taiwan in 1994 and 2004 indicates increasing ozone. The enhanced amounts are largest in monthly mean, and smallest in maximum of month. It is also pointed out the largest increase of ozone in summer. The trend analyses of monthly mean and monthly day-time average show increasing ozone concentration in most areas. In monthly average of daily maxima, the areas with decreasing trend increase. The trends of maximum of month in Nan-Tou area in spring and summer reach 1.2ppb/yr and are up to 90% confidence levels, so do the area from Tai-Chung to Tai-Nan County. The decreasing ozone trends up to 90% confidence levels only occur in Hua-Lian in spring and in Xin-Dian in summer in maximum of month. Frequency analyses of seasonal ozone show the characteristic that the frequency of the low ozone concentration bins decrease while the higher increase. It was found the property of stations, such as high polluted or clean, could be determined by its frequency distribution. The classification of total stations shows a good agreement with the area of high polluted sites and the distribution of ozone concentration up to 120ppb in maximum of month. The result indicates it is a good way to identify the property of stations by using ozone frequency distribution. The correlation between ozone and NO shows the negative correlation of monthly average of daily maxima in most Taiwan areas, especially up to 0.6 in Nan-Tou in spring and in Tai-Chung and Zhang-Hua in winter. In maximum of month, there are positive correlation in Yi-Lan, the coast of Yun-Lin and Kao-Bing area in all seasons.