2018-2019年兰州市近地面臭氧浓度变化特征及其影响因素分析

选取兰州市城区4个环境空气质量国控站点2018-2019年的监测数据和兰州市气象站同期的观测资料,分析了兰州市O₃浓度的时空分布特征,并探讨了气象因素和相关污染物对ρ(O₃-8 h)的影响。结果表明:1)兰州市城区各站点ρ(O₃-8 h)的月变化和ρ(O₃)小时值的日变化均呈单峰型,ρ(O₃-8 h)高值出现在4-8月,ρ(O₃)小时峰值出现在15:00左右;2)相关污染物与ρ(O₃-8 h)均呈负相关,ρ(O₃-8 h)随ρ(NO₂)、ρ(CO)、ρ(PM_2.5)的增加而降低;3)高温、低湿的环境有利于兰州市城区O₃的生成,而特殊的地形条件导致在一定风速下,O₃更容易积累;4)分别建立了相关污染物和气象因子的多元线性回归方程,发现在当前气象条件和相关污染物排放现状下,气象因子对兰州市O₃的影响比相关污染物的影响更为重要。

VARIATION CHARACTERISTICS AND INFLUENCE FACTORS OF SURFACE OZONE CONCENTRATION IN LANZHOU IN 2018-2019

This paper investigated temporal and spatial variations of ozone concentration in Lanzhou from 2018 to 2019 and further the effects of meteorological factors and the related pollutants on O₃-8 h were discussed based on the dataset of observation from the meteorological stations and four air monitoring stations in Lanzhou.The results indicated that:1) The monthly concentration variation of O₃-8 h showed a single peak trend in all stations in Lanzhou.The high value appeared from April to August and the low value appeared in winter.The diurnal distribution of O₃ concentration showed a single peak pattern,and the highest concentration appeared at about 15:00.2) Relevant pollutants had a negative correlation with O₃-8 h,which showed that the concentration of O₃-8 h decreased with the increase of NO₂,CO and PM_2.5.3) High temperature and low humidity were conducive to the formation of O₃ in Lanzhou,while the special topographic conditions led to the accumulation of ozone more easily under a certain wind speed.4) By establishing regression equations of multiple linear of related pollutants and meteorological factors,the effects of related pollutants and meteorological factors on O₃-8 h concentration were studied.The results showed that the influence of meteorological factors on the concentration of O₃ in Lanzhou was more important than that of the related pollutants under the current meteorological conditions and related pollutants emission status.