东北沿海城市大气中臭氧浓度时间分布特征分析

An Analysis on Temporal Distribution Characteristics of Ozone Concentration in Atmosphere at Northeast Coastal Cities in China

以东北6个沿海城市大气中臭氧浓度变化为研究对象,选取2018—2020年6个城市共计77个国控环境空气质量自动监测站24h连续监测数据,在不同时间尺度上分析臭氧年均浓度变化特征。结果表明:2018—2020年东北沿海城市臭氧浓度和臭氧污染日逐年下降,春夏季节臭氧浓度较高,超出二级标准,秋冬季臭氧浓度较低,符合二级标准。臭氧污染日基本集中在4—9月,其中,5—6月的臭氧污染日最多,臭氧日浓度最高。1—2月和11—12月臭氧日浓度最低,臭氧污染日为0。臭氧小时浓度6—7时为最低值,15—16时为最高值。

To make a study on the changes in ozone concentration in atmosphere at northeast coastal cities in China,round-the-clock monitoring data acquired at seventy seven state-controlled ambient air auto-monitoring substations in six cities in the period of 2018~2020 were chosen for analysing the variation features of annual average ozone concentration on different time scales.It has shown that the ozone concentration and number of days when suffered from ozone pollution in the northeast coastal cities in 2018 through 2020 declined year by year.Ozone concentration in spring and summer was higher over the limit value specified in Class 2 of the standard,and that in autumn and winter was lower whilst being in compliance with Class 2 of the standard.The ozone pollution suffering days were mainly concentrated in April through September whilst counted the most in May and June with the highest ozone concentration in particular.The lowest ozone concentration occurred in January,February,November and December without emerging of any ozone pollution suffering days.As regards the hourly mean ozone concentration,the lowest one appeared within 6 to 7 o’clock and the highest one at 15 to 16 o’clock.