Spatial Analysis of Atmospheric Pollutants in An-Najaf Governorate Based on Sentinel-5 Satellite Observations

Abstract

Sentinel-5P satellite imagery, in combination with Geographic Information Systems (GIS), was utilized to analyze the spatial distribution of the atmospheric pollutant gases—ozone (O₃), sulfur dioxide (SO₂), and carbon monoxide (CO)—across An-Najaf Governorate in central Iraq. The study aimed to assess patterns of pollutant concentration and identify the anthropogenic and environmental factors influencing their distribution. Sentinel-5P satellite data were processed and analyzed using ArcMap 10.8, qualifying high-resolution mapping of pollutant levels across the governorate’s nine districts with varying land uses. Results showed that CO concentrations peaked in Abbasiya, Al-Hurriyah, Al-Kufa, and Al-Qadisiyah, while SO₂ concentrations were highest in Al-Hurriyah, Abbasiya, and Haidariyah. Elevated levels of O₃ were recorded in Al-Hurriyah, Abbasiya, Haidariyah, and An-Najaf Center. Furthermore, the Normalized Difference Built-up Index (NDBI) was employed to explore the correlations between pollutant levels and urban development, revealing a strong positive relationship between gas concentrations and building density. Pearson correlation coefficients confirmed that areas with dense human activity, industrial presence, and power generation facilities experience significantly higher pollutant emissions. The study underscores the critical role of remote sensing in environmental monitoring and highlights the urgent need for sustainable urban planning to mitigate air pollution and its associated health, environmental, and economic impacts.