ABSTRACT
Ground-level ozone (O3) is a secondary pollutant produced by its precursors, such as volatile organic compounds (VOC) and nitrogen oxides (NOx) through complex photochemical reactions in sunlight. This study was aimed to investigate the relationships of surface ozone with its precursors in the urban and rural locations in Pingtung County. Atmospheric measurements of hydrogen peroxide (H2O2) and nitric acid (HNO3) were conducted at the two sites, namely Pingtung city and Chaochou, in Pingtung County during three consecutive days of fall, winter and spring seasons in 2002-2003, from which the ozone-VOC-NOx sensitive regimes were derived using two methods, namely the indicator ratios of H2O2/HNO3 and O3/HNO3 developed by Sillman (1997), and the extent parameter, E, of SPM (Smog Production Model) developed by Blanchard (1994).
According to the indicator ratios of H2O2/HNO3 = 0.3 ¡V 0.6, O3/HNO3 = 12 -16 (Sillman, 1997), results at the Pingtung site show that VOC-limited regimes occupy about 68% in autumn, winter and spring. Results at the Chaochou site show that VOC-limited regimes occupy about 52.8% in autumn and winter, while NOx-limited regimes occupy about 54.2% in spring.
According to the critical value of extent parameter, Ecrit = 0.7 (Blanchard, 1994), results show that VOC-limited regimes predominate (93.8%) at Pingtung site in winter and spring. Results at the Chaochou site show that VOC-limited regimes predominate (87.5%) in winter, while NOx-limited regimes predominate (58.3%) in spring.
In summary, the ozone-VOC-NOx sensitivity results derived from indicator ratios agree fairly well with SPM results. The indicator ratios and Ecrit are frequently considered to be universal under given assumptions. However, these values may vary with meteorology and topography. Further studies are needed to characterize these parameters locally.
Identifer | oai:union.ndltd.org:NSYSU/oai:NSYSU:etd-0620103-142755 |
Date | 20 June 2003 |
Creators | Peng, Yen-Ping |
Contributors | Kang-Shiang Chen, Rui-Ren Chen, Ming-Shian Jou |
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-0620103-142755 |
Rights | unrestricted, Copyright information available at source archive |
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