Identifying Micro-Level Pollution Hotspots Using Sentinel-5P for the Spatial Analysis of Air Quality Degradation in the National Capital Region, India

Abstract

Rapid urbanization and industrialization have significantly impacted the air quality in India’s National Capital Region (NCR), posing severe environmental and public health challenges. This study aims to identify micro-level pollution hotspots and assess air quality degradation in the NCR. This study integrates Sentinel-5P satellite data with ground station air quality measurements. Geographic Information System (GIS) techniques and regression analysis are employed to refine and validate satellite-derived air quality data across the NCR. Analysis reveals variable pollution levels across the NCR, with significant concentrations of nitrogen dioxide (NO2) in the East and North-East, and carbon monoxide (CO) in the Central region. Aerosol Index identifies the East and North-East as critical hotspots due to industrial activities and construction dust. Particulate matter concentrations often exceed national standards during the colder months, with particulate matter (PM2.5) and (PM10) levels reaching up to 300 µg/m3 and 350 µg/m3, respectively. Ground-based data confirmed high levels of ozone (O3) in the North-West, reaching up to 0.125 ppm, emphasizing the impact of vehicular and industrial emissions. The integration of satellite imagery and ground data provided a comprehensive view of the spatial distribution of pollutants, highlighting critical areas for targeted air quality interventions. The findings underscore the need for sustainable urban planning and stricter emission controls to mitigate air pollution in the NCR. Enhanced pollution monitoring and control strategies are essential to address the identified hotspots, particularly in the East, North-East, and Central regions.