Assessment of the Spatial and Seasonal Aerosols Distribution During 2017 Winter and Spring, in San Juan City, Argentina

The aim of this work is to assess the horizontal distribution of aerosols during winter and spring 2017, in San Juan city, Argentina, and its relationship with the land use. The concentration of PM2.5 at ground level in 54 points of the city and the aerosol optical deep were measured. A supervised classification to obtain a land use map was performed. Statistical analysis was carried out considering 5 variables values in the 54 points, related to the particulate material (PM) emission: AOD, LST, NDVI, NDWI from satellite products and PM2.5 from field measurements. The data were analyzed considering the spatial, seasonal and meteorological variation, and the land use classes.The results indicate that 3 concentric rings can be considered in the studied area and 4 zones are distinguished: urban, peri-urban, periphery and industrial. The average PM2.5 concentrations was 18.7 μg/m3, and the season of maximum concentration was in winter. For AOD the average was 0.83, and the maximum registered during spring. PM2.5 concentrations presented a Pearson’s correlation coefficient with AOD higher than 0.65 in areas classified as peri-urban and industrial periphery. Regarding the meteorological variables, LST and wind showed the highest correlation with AOD and PM2.5. NDVI and NDWI present negative correlation with aerosol concentrations, so in areas with more vegetation and higher soil moisture which indicates that aeolian soil erosion is an important PM emission.