郑州市臭氧变化特征及影响因素分析

Analysis on the Characteristics and Influencing Factors of Ozone Change in Zhengzhou

利用2017-2019年郑州市臭氧(O_(3))浓度数据和气象数据资料,分析了郑州市O_(3)污染时间变化特征及其与前体物和气象因子之间的关系.结果表明:郑州市以O_(3)为首要污染物的天数逐年增加,2019年上升为148 d,约占一年总天数的40.55%,说明O_(3)污染越来越严重;郑州市O_(3)浓度具有明显的季节变化,呈现出夏季>春季>秋季>冬季的特征,6月O_(3)污染最为严重,3年来O_(3)月均浓度均超过170μg·m^(-3);O_(3)与NO_(2)、CO月浓度呈负相关关系.在O_(3)浓度与气象因素的相关性分析中表明,O_(3)浓度与温度呈显著正相关,而与气压的相关性刚好相反,与相对湿度和降水量均呈现出弱的负相关性,与风速呈现出弱的正相关性.重污染案例研究表明,在高温、低湿、低压及一定风速条件下有利于O_(3)的生成与累积.

Based on the concentration data of ozone,nitrogen dioxide and carbon monoxide in Zhengzhou City from 2017 to 2019 and the meteorological data of Zhengzhou City,this paper analyzed the temporal variation characteristics of ozone pollution in Zhengzhou City and its relationship with precursors and meteorological factors.The results showed that the number of days with ozone as the primary pollutant in Zhengzhou increased year by year,and it increased to 143 days in 2019,accounting for 40.55%of the total number of days in a year,indicating that ozone pollution was becoming more and more serious.The ozone concentration in Zhengzhou City had obvious seasonal changes,showing the characteristics of summer>spring>autumn>winter.In June,ozone pollution was the most serious,with the average monthly concentration exceeding 170μg·m^(-3) in the past three years.Ozone was negatively correlated with the monthly concentrations of nitrogen dioxide and carbon monoxide.According to the correlation analysis between ozone concentration and meteorological factors,the correlation between ozone concentration and temperature is significantly positive,while that between ozone concentration and air pressure is just opposite.The correlation between ozone concentration and relative humidity is not significant,and the correlation with both precipitation and wind speed is weak.The case study of heavy pollution shows that under the conditions of high temperature,low humidity,low pressure and certain wind speed,it is beneficial to the formation and accumulation of ozone.