北碚区气溶胶光学厚度特征及其与颗粒物浓度的相关性

Characteristics of Aerosol Optical Depth in the Urban Area of Beibei and Its Correlation with Particle Concentration

为了解重庆市北碚区大气质量状况,利用其2014年气溶胶光学厚度和颗粒物质量浓度的同步观测结果进行分析.结果表明,北碚区AOD500 nm的年均值为1.46±0.69,其随月份变化明显,其中11月最高为2.90±1.85, 9月最低为0.54±0.05.北碚区存在颗粒物污染的现象,PM2.5和PM10的年均值分别为(62±40)μg·m^-3和(94±51)μg·m^-3,均超出GB 3095-2012《环境空气质量标准》二级标准限值,PM2.5与PM10的日均值超标率分别为26%和15%.细粒子PM2.5与可吸入颗粒物PM10浓度之间呈现显著性相关,全年决定系数R^2能够达到0.95(P<0.01),AOD与PM2.5、 PM10之间全年均呈正相关特性,全年决定系数R^2分别为0.48和0.46,且不同季节下的决定系数和相关函数均有差异,其中冬季相关性最好,夏季相关性最差.全年AOD与AQI呈正相关特性,决定系数R2为0.15(P<0.05).AOD值受天气要素综合作用的影响,观测期间也应将温度、湿度、水汽等要素数据进行同步采集.

To understand the atmospheric quality of the Beibei District of Chongqing, using the simultaneous observation data of aerosol optical depth and particulate matter concentration in 2014, we analyzed the characteristics of aerosol optical depth(AOD) in the urban area of Beibei and its correlation with particle concentration. The results showed that the annual average of AOD500 nm in Beibei District is 1.46±0.69, which varies significantly by month. The highest value in November was 2.90±1.85, and the lowest in September was 0.54±0.05. There is particulate matter pollution in Beibei District. The annual average values of PM2.5 and PM10 are(62±40)μg·m^-3 and(94±51)μg·m^-3, respectively, which exceed the secondary standard of GB 3095-2012 Ambient Air Quality Standard. The limit values, the daily average over-standard rates of PM2.5 and PM10, are 26% and 15%, respectively. There was significant correlation between fine particle PM2.5 and PM10 concentration of respirable particulate matter. The annual coefficient of determination R2could reach 0.95(P<0.01). The correlation between AOD and PM2.5 and PM10 was positive throughout the year. The coefficient of determination R^2 was 0.48 and 0.46, respectively, and the coefficient of determination and correlation function were different in different seasons, among which the correlation in winter was the best and the correlation in summer was the worst. AOD and air quality index showed positive correlation characteristics throughout the year, and the coefficient of determination R^2 was 0.15(P<0.05). The AOD value was affected by the comprehensive effects of weather elements. The temperature, humidity, water vapor, and other factor data should also be collected synchronously during the observation period.