2017年郑州市臭氧浓度特征及气象因素分析

Analysis of Ozone Concentration Characteristics and Meteorological Factors in Zhengzhou in 2017

利用2017年郑州市9个国控空气质量监测站点(国控点)的小时监测数据及气象数据,分析郑州市O_(3)浓度的污染特征,O_(3)浓度与PM_(2.5)、PM_(10)及NO_(2)浓度的关系,以及影响O_(3)浓度的气象条件。结果表明:2017年郑州市9个国控点的O_(3)-8 h超标天数为750天,占总天数的22.8%。夏季O_(3)污染最为严重,超标天数占总天数的56.5%,春季、秋季的次之,冬季无站点超标,郊区的O_(3)污染比城区的严重。O_(3)浓度日变化呈单峰型,O_(3)浓度白天郊区的高于城市的,夜间城市的高于郊区的。PM_(10)、PM_(2.5)和NO_(2)浓度月变化呈现冬季高、夏季低的趋势。PM_(10)、PM_(2.5)浓度日变化呈现白天的低、夜间的高的趋势,NO_(2)浓度日变化呈双峰型,峰值分别出现在07-09时、19-22时。O_(3)浓度和超标率随温度升高而显著升高,随相对湿度升高而降低,风速为3~4 m/s时,O_(3)浓度超标率最大。因此高温低湿、3~4 m/s的微风等条件有利于郑州地区O_(3)浓度的累积。

This paper analyzes the pollution characteristics of ozone(O_(3))concentration,the relationship between O_(3) and PM_(2.5),PM_(10) and NO_(2),and the meteorological conditions affecting O_(3) concentration in Zhengzhou City using hourly monitoring data and meteorological data from 9 national air quality monitoring stations in Zhengzhou in 2017.The results show that the number of non-attainment days about O_(3)-8 h at the 9 national monitoring sites in Zhengzhou in 2017 was 750 d,accounting for 22.8% of the total number of the days.The O_(3) pollution is the most serious in summer with the number of non-attainment days accounting for 56.5%,followed by spring and autumn. There is no non-attainment day in winter.The O_(3) pollution is more severe in suburban areas than in urban areas.The diurnal variation of O_(3) concentration shows a single peak.The O_(3) concentration is higher in the suburbs than in the city in the daytime,but the situation is opposite at night.The monthly variations of PM_(10),PM_(2.5),and NO_(2) show up the pattern of“higher in winter and lower in summer”.The diurnal concentration variations of PM_(10) and PM_(2.5) show the trend of“higher at night and lower in daytime”,while the concentration of NO_(2) shows double peaks with the maximum values appearing in 07:00-09:00 and 19:00-22:00,respectively.The O_(3) concentration and non-attainment rate rise upward obviously with the increase of temperature but decline with the increase of relative humidity.The O3 non-attainment rate is the highest when the wind speed is in 3-4 m/s.So the conditions of high temperature,low humidity with wind at the speed of 3-4 m/s are favorable for the O_(3) concentration accumulation in Zhengzhou.