The Nitrogen dioxide (NO2) is one of the main pollutant gases in the atmosphere with known harmful effects on human health, caused by rapid urbanization, traffic, and industrialization. In the fast-growing urban areas of North Africa, NO2 spatiotemporal variability analysis is hampered by the sparse distribution of ground stations. In neighboring Morocco, particularly in the Casablanca-Settat region, research that utilizes satellite data analysis in combination with geospatial statistical analysis is also limited. The purpose of this study is to fill the scientific gap in spatial variability analysis of NO2 concentrations from 2018 to 2025 in a specific region in Casablanca-Settat in Morocco. The NO2 concentration in the tropospheric region using the Sentinel-5P (TROPOMI) satellite sensor was analyzed using geospatial analysis tools. The hotspots and cold spots of NO2 were determined using the Getis-Ord Gi∗ statistic at a statistically significant confidence level. The annual average NO2 concentration varied between 6.3 μg/m3 in rural areas in southern provinces to 11.3 μg/m3 in Casablanca, showing sharp differences between the urban, industrial areas, and rural areas. The cities of Casablanca, Mediouna, and the Nouaceur province showed higher NO2 concentrations than other cities in any country in the world; they often exceeded the annual average recommended by the World Health Organization at 10 μg/m3. However, southern provinces, such as Settat, Sidi Bennour, and El Jadida, had smaller NO2 concentrations that were less variable. A marked decrease in NO2 was observed during the COVID-19 lockdown period, followed by a stabilized period in 2022–2023 and a decline in NO2 thereafter. The NO2 hotspots were in the Casablanca-Beth Mohammedia-Mediouna-Berrechid region at a 99 % confidence level, which was a hotspot region, but in southern areas, it was a cold spot region.
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