Assessing CO and NO2 concentrations in urban regions of Argentina: a satellite data analysis

Abstract

Understanding and characterizing atmospheric pollutant concentrations provides crucial insights into the air quality exposure faced by the population. However, in Argentina, studies on atmospheric pollutants are constrained by the sparse distribution of monitoring stations and the specificity of existing research, which often focuses on particular regions and time periods. In this context, satellite data have emerged as invaluable tools, allowing for the monitoring of vast areas of the country where traditional measurements are sparse or inaccessible. In this study, we present an analysis of the annual and interannual concentration profiles of NO₂ and CO in regions with significant anthropogenic or industrial activity across Argentina, including the Buenos Aires Metropolitan Area, Bahía Blanca, Rosario, Córdoba, Mendoza, and Vaca Muerta. Utilizing data from TROPOMI, OMI, and MOPITT sensors spanning from 2010 to 2023, we conduct a comparative analysis to determine temporal trends and spatial variations in pollutant concentrations. Our findings reveal a high level of agreement between the sensors regarding the maximum and minimum values of the measurements. However, greater data dispersion is observed for NO₂ between the two satellites, mainly due to differences in orbit times and its higher reactivity. Both pollutants exhibit annual cycling patterns, with concentrations varying in response to temperature fluctuations. Furthermore, our analysis highlights the strong influence of anthropogenic activities on NO₂ concentrations, such as vehicle emissions and industrial processes, while CO levels are more homogeneous among sites, and are primarily influenced by the presence of fires in the region.