Spatio-Temporal Assessment of Urban AIr Pollution in Hanoi Using Sentinel-5p Tropomi and Terra Modis Observations

Air pollution has become one of the most serious environmental challenges in rapidly developing urban areas, particularly in Hanoi, Vietnam. This study presents an integrated multi-pollutant framework updating the continuous spatial mapping of atmospheric pollutants, including NO2, SO2, O3 and PM2.5 over Hanoi for the year 2025. Satellite data from Sentinel-5P TROPOMI and Terra MODIS in 2025 were pre-processed, integrated, and interpolated to construct spatial datasets for the entire Hanoi region. Spatio-temporal variations in pollutant concentrations were analyzed to identify hotspots and seasonal patterns. The results reveal significant differences in the distribution of pollutants between the urban core and suburban areas, with higher concentrations observed during the dry season. The study highlights the potential of satellite-based monitoring as a complement to ground-based observation systems, providing valuable datasets to support environmental management and policy-making.