江苏省县域PM_(2.5)浓度时空变化特征研究

Temporal and Spatial Characteristics of PM_(2.5) Concentration in Counties of Jiangsu Province

文章利用江苏省2017年-2022年环境空气质量监测数据,分析了全省县域细颗粒物(PM_(2.5))浓度时空变化特征,与气象因素的相关关系,并比较了与主城区PM_(2.5)浓度的差异。结果显示,江苏省县域PM_(2.5)浓度呈逐年下降趋势,5年降幅为25.4%,年均下降速率为2.1μg/(m 3.a)。空间分布呈“西北部偏高,东南部偏低”的特征。与气象因素的相关性表明,县域PM_(2.5)月均浓度整体与月均气温、月均风速呈显著负相关,但仅个别月份,与月均相对湿度呈负相关。与主城区PM_(2.5)平均浓度相比,县域平均浓度整体较低,但二者浓度差呈现逐年迅速减小趋势,从日变化看,二者浓度差最大出现在上下班高峰时段。

Based on ambient air monitoring data of Jiangsu province during 2017-2022,this work analyzes temporal and spatial characteristics of PM_(2.5) concentration of Jiangsu counties,correlation with meteorological factors,and compares with that in urban areas.The results indicate:PM_(2.5) concentration in Jiangsu counties shows a downward trend year by year,and 5-year drop is 25.4% with an average annual decline rate of 2.1μg/(m 3.a).In terms of spatial distribution,PM_(2.5) concentration is higher in northwest counties,and lower in southeast.The correlation with meteorological factors shows that the average monthly PM_(2.5) concentration in the county is negatively correlated with average monthly temperature and average monthly wind speed.Compared with PM_(2.5) concentration in urban areas,the average PM_(2.5) concentration in counties is lower,but the concentration difference between both shows a rapidly decrease trend year by year.In terms of diurnal variation,the maximum concentration difference between both appears in the rush hours.