张家口市空气质量变化特征及其与气象要素的关系分析

Analysis of Characteristics of Air Quality Change in Zhangjiakou City and Its Relationship with Meteorological Elements

整理与统计张家口市2014—2019年逐日空气质量指数(AQI)数据,结合同期气象观测资料,重点分析了张家口市空气质量变化特征、主要污染物变化特征及其与气象要素之间的关系。结果表明:2014—2019年张家口市整体空气质量水平均为良。年平均AQI随着年份的增加而呈现出一定的减少趋势,其空气质量呈逐年好转趋势。夏季空气质量最差,秋季空气质量最好,以7月份空气质量最差。空气污染物主要包括PM_(2.5)、PM_(10)、SO_(2)、NO_(2)、O_(3)等,除O_(3)的质量浓度呈上升趋势外,其他各种污染物均呈不同程度的下降趋势。PM_(2.5)与SO_(2)浓度为冬季最高,夏季最低;O_(3)的浓度为夏季最高,而冬季最低;PM_(10)质量浓度为春季最高,而夏季最低;NO_(2)的质量浓度为秋冬季较高,而夏季最低。张家口市空气质量变化与温度、降水、相对湿度与风速等气象要素均密切相关,且与以上气象要素均呈负相关关系。

In this paper,daily Air quality index(AQI)data of Zhangjiakou City from 2014 to 2019 were collected and analyzed,and combined with meteorological observation data of the same period,the change characteristics of air quality,the change characteristics of main pollutants and their relationship with meteorological elements in Zhangjiakou City were analyzed.The results showed that the overall air quality was good in Zhangjiakou from 2014 to 2019.The annual average AQI showed a decreasing trend with the increase of years,and the air quality showed an improving trend year by year.The air quality was worst in summer,best in autumn and worst in July.Air pollutants mainly include PM_(2.5),PM_(10),SO_(2),NO_(2),O_(3) and other types.Except the mass concentration of O_(3),which shows an upward trend,other pollutants show a downward trend to varying degrees.The concentrations of PM_(2.5) and SO_(2) were the highest in winter and the lowest in summer.The concentration of O_(3) was the highest in summer and the lowest in winter.The mass concentration of PM_(10) was the highest in spring and the lowest in summer.The mass concentration of NO_(2) was higher in autumn and winter,and the lowest in summer.The change of air quality in Zhangjiakou City was closely related to the meteorological factors such as temperature,precipitation,relative humidity and wind speed,and has a negative correlation with the above meteorological factors.