北京边界层大气污染物的垂直廓线监测与分析

基于扫描差分光学吸收光谱（DOAS）系统，于2007年8月27日~9月4日期间对北京市朝阳区大气污染物SO₂，HCHO，O₃和NO₂的垂直分布进行了连续监测，并对污染物垂直廓线进行了分析，详细探讨了SO₂垂直分布特征以及夜间NO对O₃的滴定作用.结果表明，SO₂浓度通常没有明显垂直分层分布特征，但在清晨风速较低时呈现负梯度变化.研究发现夜间O₃、NO和NO₂之间存在稳态作用，表明城市区域O₃的滴定主要来自于地面NO的直接排放，显示出NO的滴定作用对夜间O₃、NO和NO₂的垂直变化起到重要作用.

Monitoring and analysis for vertical profiles of air pollutants in boundary layer of Beijing

Based on the scanning differential optical absorption spectroscopy (DOAS) system, vertical distribution of air pollutants (SO₂, HCHO, O₃ and NO₂) were observed continuously from Aug 27, 2007 to Sep 4, 2007 in Chaoyang District of Beijing and their vertical profiles were analyzed. The typical vertical variation characteristic of SO₂ and nocturnal NO titration to O₃ were discussed. The results indicated that the gradient of SO₂ was not obvious, and the negative gradient appeared during the morning hours when wind speed was low. The measurement also clearly showed the dominant role of NO titration for vertical variations of nocturnal chemistry in urban areas and O₃ concentrations was mainly influenced by the direct emissions of NO.