拉萨市臭氧浓度时空分布变化特征分析

Study on the spatiotemporal distribution characteristics of ground level ozone concentration in Lhasa

为掌握拉萨市臭氧质量浓度的时空分布特征和相关因子变化趋势,文章对全国空气质量实时发布平台发布的2017年拉萨市6个国控城市环境空气自动监测站点的臭氧监测数据进行了分析。结果表明,2017年拉萨市臭氧年评价浓度达到国家二级标准;臭氧质量浓度呈现出明显的季节、月份、日小时变化特征:春季最高、冬季最低,5月为臭氧浓度最高的月份,在每日17:00和19:00时臭氧浓度达到峰值;宗教活动较为集中的八廓街臭氧浓度明显高于其他点位;臭氧质量浓度受氮氧化物、二氧化氮、PM2.5、湿度、温度和风速的共同影响,与氮氧化物、二氧化氮、PM2.5和湿度呈较显著的负相关性,与温度和风速呈较显著的正相关性。

in order to study the spatial and temporal distribution characteristics of ground level ozone concentration in Lhasa and variations of its related factors,in this paper,ground level ozone concentration data,which was collected in 2017 at six automatic environmental air monitoring stations located in Lhasa and was released by the national air quality real-time publishing platform,was analyzed.The results show that the ground level ozone concentration found in Lhasa is in the range of class II of the national ambient air quality standard,and show a significant variation with season,month and day,with the highest concentration in spring and the lowest concentration in winter.And the monthly highest concentration was found in May and daily highest concentration was found between 17:00 pm and 19:00 pm.It also shows that the ground level ozone concentration are generally higher around Barkor street where the most religion activities take place.Moreover,our result shows a significant negative correlation between ground level ozone concentration and nitrogen oxide,nitrogen dioxide,PM2.5 as well as humidity,and a positive correlation between ozone concentration and temperature and wind speed.