Satellite-based tropospheric pollutant monitoring using sentinel-5P: An end-to-end processing and analysis framework

Air quality monitoring has traditionally relied on sparse ground-based measurement networks, limiting spatial coverage and accessibility in data-poor regions. Satellite remote sensing, particularly the Sentinel-5 Precursor (S5P) mission’s Tropospheric Monitoring Instrument (TROPOMI), offers unprecedented opportunities for global atmospheric composition monitoring at high spatial and temporal resolution. This paper presents a comprehensive methodological framework for acquiring, processing, and integrating Sentinel-5P satellite data for air quality estimation. We detail the complete workflow from data discovery and download through the Copernicus Data Space Ecosystem (CDSE) API, extraction and preprocessing of Level-2 geophysical products, integration with reanalysis meteorological data, physical conversion of satellite column measurements to surface-level concentrations, and rigorous quality assurance procedures. Specific attention is given to the critical role of Planetary Boundary Layer Height (PBLH) from ERA5 reanalysis in converting satellite-observed atmospheric column densities to ground-level pollutant concentrations. This framework demonstrates how open-access satellite data and modern cloud-based processing infrastructure enable researchers in all regions to access high-quality air quality data without dependence on costly proprietary systems. The methodology is globally scalable and applicable to multiple pollutant species, including nitrogen dioxide (NO_₂), sulfur dioxide (SO_₂), carbon monoxide (CO), and ozone (O_₃), making it an essential resource for air quality researchers, environmental scientists, and policy makers seeking to understand and address air pollution on a global scale [5][13].