2013—2016年74城市臭氧浓度变化特征

Characteristics of Ozone Concentration Variation in 74 Cities from 2013 to 2016

利用2013—2016年74城市臭氧(O_3)监测数据,综合探讨了全国74城市O_3浓度时空变化特征、变化趋势。结果表明:2013—2016年,74城市O_3-8 h各百分位浓度总体呈上升趋势,且百分位较高区间O_3浓度逐年上升速率越快,O_3-8 h第95百分位浓度年增长5.3μg/m3,其次是第90百分位;O_3区域性污染特征明显,京津冀及周边、长三角、珠三角O_3污染问题突出;74城市O_3浓度超标天数年增长3 d/城市,O_3污染呈明显日、季节变化特征,午后14:00—17:00达到小时浓度峰值,超标日主要集中于5—10月;O_3对环境空气质量综合指数贡献率逐年增加,北京、上海和广州O_3贡献率年增长分别为1.9%、1.1%和0.8%。

Based on the O3 monitoring data in 74 cities from 2013 to 2016,a comprehensive discussion on the O3 concentration characteristics and variation trend was carried out. The results showed that the whole O3-8 h percentile concentrations were increasingly prominent and the higher percentile concentration had faster growth rate. Annual 95 thpercentile O3-8 h concentration was rising with a growth rate of 5. 3 μg/m3,followed by the 90thpercentile; O3 showed significant regional pollution characteristics,Beijing-Tianjin-Hebei and the surrounding area,Yangtze river delta,the Pearl River delta were three key regions having the most projecting O3 problems. Annual O3 nonattainment days were rising with a growth rate of 3 days/city.O3 concentration had obvious diurnal and seasonal characteristics. O3 nonattainment days mainly occurred from May to October,and O3 diurnal peak concentration occurred at about 14： 00 to 17： 00. Annual growth rate of O3 contribution to the comprehensive air quality index was rising,the growth rates of Beijing,Shanghai,Guangzhou were 1. 9%,1. 1% and 0. 8% respectively.