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

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 AOD_500nm 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 PM_2.5 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 PM_2.5 and PM₁₀, are 26% and 15%, respectively. There was significant correlation between fine particle PM_2.5 and PM₁₀ concentration of respirable particulate matter. The annual coefficient of determination R² could reach 0.95 (P<0.01). The correlation between AOD and PM_2.5 and PM₁₀ was positive throughout the year. The coefficient of determination R² 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 R² 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.