大同市PM_(2.5)和PM_(10)浓度变化特征及其与气象因子的关系

Characteristic of PM_(2.5) and PM_(10) Concentration Variation in Datong City and Their Relationship with Meteorological Factors

目的 探究大同市一年中空气可悬浮颗粒物浓度变化特征及其与气象因子的关系。方法 以大同市御东区为研究区域,收集2022年3月—2023年2月PM_(2.5)和PM_(10)质量浓度、气温、相对湿度和风速等数据,分析PM_(2.5)和PM_(10)浓度的月变化和季节变化情况及其与温度、相对湿度和风速的关系。结果 2022年PM_(2.5)和PM_(10)的月变化曲线均呈现出两头高中间低的U形变化规律及冬高夏低、春秋居中的季节性特征。全年PM_(2.5)浓度在12~25μg/m~3,较低值集中在5-12月,最高值出现在1-3月。PM_(10)质量浓度变化在66~106μg/m^(3)区间,最低值出现在5-7月,最高值出现在1-3月;PM_(10)与气温呈现极显著的负相关,与相对湿度和风速之间的相关性不显著;PM_(2.5)与温度、相对湿度和风速三个气象指标之间的相关性都不显著。结论 2022年大同空气质量整体良好,PM_(2.5)和PM_(10)浓度表现出明显的季节性特征,春末及夏季、秋初PM_(2.5)和PM_(10)污染相对较轻,冬季污染较重。

Objective To study the variation characteristics of suspended particulate matter concentration and their relationship with meteorological factors in Datong City in a year.Method Taking the Yudong District of Datong City as the research area,the data of PM_(2.5) and PM_(10) mass concentrations,air temperature,relative humidity and wind speed were collected from March 2022 to February 2023,the monthly and seasonal changes of PM_(2.5) and PM_(10) concentrations and their relationship with air temperature,relative humidity and wind speed were analysized.Results The monthly change variation curves of PM_(2.5) and PM_(10) in 2022 both exhibited a U-shaped with higher concentrations at the beginning and end and lower concentrations in the middle of the year.They also displayed a seasonal pattern with higher concentrations in winter and lower concentrations in summer,and intermediate concentrations in spring and autumn.The annual concentration of PM_(2.5)ranged from 12 to 25 μg/m^(3),with lower values concentrated between May and December,and the highest values occurring from January to March.PM_(10) mass concentration varies between 66 and 106 μg/m~3,with the lowest values observed from May to July and the highest values from January to March.PM_(10) showed a highly significant negative correlation with temperature and no significant correlation with relative humidity and wind speed.On the other hand,PM_(2.5) did not exhibit significant correlations with temperature,relative humidity,and wind speed.Conclusion The air quality in Datong was generally good in 2022.Both PM_(2.5) and PM_(10) concentrations exhibited distinct seasonal characteristics,with lighter pollution in late spring,summer,and early autumn,and heavier pollution in winter.