https://scholars.lib.ntu.edu.tw/handle/123456789/331109
標題: | Photochemical production of ozone and control strategy for Southern Taiwan | 作者: | Shiu, CJ Liu, SC Chang, CC Chen, JP Chou, CCK Lin, CY Young, CY JEN-PING CHEN |
關鍵字: | Atmospheric oxidants; Ozone; Ozone control strategy; Ozone production; Precursors | 公開日期: | 2007 | 卷: | 41 | 期: | 40 | 起(迄)頁: | 9324-9340 | 來源出版物: | Atmospheric Environment | 摘要: | An observation-based method (OBM) is developed to evaluate the ozone (O3) production efficiency (O3 molecules produced per NOx molecule consumed) and O3 production rate (P(O3)) during a field campaign in southern Taiwan. The method can also provide an estimate of the concentration of OH. A key step in the method is to use observed concentrations of two aromatic hydrocarbons, namely ethylbenzene and m,p-xylene, to estimate the degree of photochemical processing and amounts of photochemically consumed NOx and NMHCs by OH. In addition, total oxidant (O3+NO2) instead of O3 itself turns out to be very useful for representing ozone production in the OBM approach. The average O3 production efficiency during the field campaign in Fall (2003) is found to be about 10.2±3.9. The relationship of P(O3) with NOx is examined and compared with a one-dimensional (1D) photochemical model. Values of P(O3) derived from the OBM are slightly lower than those calculated in the 1D model. However, OH concentrations estimated by the OBM are about a factor of 2 lower than the 1D model. Fresh emissions, which affect the degree of photochemical processing appear to be a major cause of the underestimate. We have developed a three-dimensional (3D) OBM O3 production diagram that resembles the EKMA ozone isopleth diagram to study the relationship of the total oxidant versus O3 precursors. The 3D OBM O3 production diagram suggests that reducing emissions of NMHCs are more effective in controlling O3 than reducing NOx. However, significant uncertainties remain in the OBM, and considerable more work is required to minimize these uncertainties before a definitive control strategy can be reached. The observation-based approach provides a good alternative to measuring peroxy radicals for evaluating the production of O3 and formulating O3 control strategy in urban and suburban environments. © 2007 Elsevier Ltd. All rights reserved. |
URI: | http://scholars.lib.ntu.edu.tw/handle/123456789/331109 | DOI: | 10.1016/j.atmosenv.2007.09.014 | SDG/關鍵字: | Concentration (process); Ethylbenzene; Nitrogen oxides; Oxidants; Photochemical reactions; Uncertainty analysis; Atmospheric oxidants; Control strategies; Ozone production; Precursors; Ozone; aromatic hydrocarbon; ethylbenzene; nitric oxide; oxidizing agent; oxygen; ozone; xylene; comparative study; emission control; nitrogen oxides; nonmethane hydrocarbon; observational method; one-dimensional modeling; ozone; peroxy radical; photochemistry; air quality; article; environmental factor; meteorology; methodology; molecule; photochemistry; priority journal; suburban area; Taiwan; Asia; Eurasia; Far East; Taiwan |
顯示於: | 大氣科學系 |
在 IR 系統中的文件,除了特別指名其著作權條款之外,均受到著作權保護,並且保留所有的權利。