成都平原夏季臭氧浓度特征分析

Analysis on the Characteristics of Summer Ozone Concentration in Chengdu Plain

摘要: 为了定量分析成都平原地面臭氧浓度特征及其气象成因，利用多个国控监测站点污染物浓度实时数据和中国气象地面观测数据，对2017~2019年夏季成都平原六市的臭氧浓度进行分析。结果表明：1) 夏季成都平原各的市臭氧浓度分布有明显差异，成都市部分地区呈重度污染，雅安市臭氧水平为良。2) 根据月份分析可知，7月臭氧浓度逐年下降，8月臭氧浓度逐年上升。3) O₃浓度日变化呈“单峰型”，8:00左右处于一天中的最低值，16:00左右达峰值。4) O₃为成都平原夏季首要污染物。5) 臭氧浓度与温度呈明显正相关性，与相对湿度呈明显负相关性，与能见度有较好正相关性，与3小时变压有较好负相关性；温度大于25℃、相对湿度小于70%、风速为0~2 m/s时，出现臭氧污染的概率增加。

Abstract: In order to quantitatively analyze the characteristics and meteorological causes of the ground ozone concentration in the Chengdu Plain, and the real-time data of pollutant concentration at multiple national control monitoring sites and the observation data of the Chinese meteorological ground were used to analyze the ozone concentration in 6 cities in the Chengdu Plain in the summer of 2017-2019. The results show that: 1) There are significant differences in the distribution of ozone concentration in the cities of Chengdu Plain in summer. Some areas in Chengdu are heavily polluted, and the ozone level in Ya’an is good. 2) According to monthly analysis, the ozone concentration decreased year by year in July, and the ozone concentration increased year by year in August. 3) O₃ concentration is “single peak”, which is at the lowest value of the day around 8:00, reaching around 16:00 Peak; 4) O₃ is the main pollutant in the Chengdu Plain in summer; 5) The ozone concentration is significantly positively correlated with temperature and negatively correlated with relative humidity. It has a good positive correlation with visibility and a good negative correlation with the 3-hour pressure change; when the temperature is greater than 25˚C, the relative humidity is less than 70%, and the wind speed is 0 - 2 m∙s−1, the probability of ozone pollution increases.