Seraing, nestled in the Walloon region of Belgium, occupies a strategic yet complex geographical position. Situated along the Meuse River at coordinates 50.5986° N, 5.5122° E, the city’s terrain is characterised by the undulating hills typical of the Condroz plateau, gradually descending towards the river valley. This topography influences air circulation, potentially creating localised pockets of stagnant air. Seraing forms part of the Liège metropolitan area, a historically industrial heartland. The legacy of heavy industry – steel production in particular – is deeply embedded in the city’s landscape and continues to impact air quality. Surrounding Seraing are agricultural lands to the east and south, while the urban–rural gradient is relatively sharp as one moves away from the Meuse valley. The river itself, while providing a transport corridor, can also contribute to humidity and potential temperature inversions, trapping pollutants. Proximity to the larger industrial zones of Liège exacerbates pollution risks, with prevailing winds often carrying emissions towards Seraing. The city’s location within a river valley, combined with its industrial past and surrounding landscape, creates a unique set of challenges for maintaining clean air.

Seraing’s air quality follows a distinct seasonal pattern. Winter, from November to February, typically sees the poorest air quality. Low temperatures and frequent temperature inversions trap pollutants emitted from heating systems and residual industrial activity near the ground. Calm wind conditions further exacerbate this, leading to higher concentrations of particulate matter. Spring (March-May) brings gradual improvement as temperatures rise and rainfall increases, washing away some pollutants. However, agricultural activities can contribute to ammonia emissions. Summer (June-August) generally offers the cleanest air, aided by stronger winds and higher atmospheric mixing. However, occasional heatwaves can lead to ozone formation, a secondary pollutant. Autumn (September-October) sees a deterioration in air quality as heating systems are reactivated and meteorological conditions become more stable. Fog, common during autumn and winter mornings, can trap pollutants and reduce visibility. Sensitive individuals – children, the elderly, and those with respiratory conditions – should limit strenuous outdoor activity during winter months and periods of fog. Monitoring pollen levels is also advisable during spring. Avoiding peak traffic hours can further reduce exposure.