Djendel, nestled along Algeria’s Mediterranean coast in the Aïn Defla State, occupies a unique geographic position that significantly influences its air quality. Situated at approximately 36.2186° N, 2.4089° E, the city benefits from a relatively low elevation, averaging around 20 meters above sea level, which minimizes the natural dispersion of pollutants. The surrounding landscape is a blend of coastal plains and gently rolling hills, transitioning into the more rugged terrain of the Tell Atlas mountains to the south. This proximity to the mountains can create localized topographic effects, trapping air masses and exacerbating pollution episodes. Djendel’s coastal location means it’s susceptible to sea breezes, which can both dilute pollutants and, under certain conditions, transport them from nearby industrial areas. The urban–rural gradient around Djendel is gradual, with agricultural zones, primarily focused on cereal crops and olive groves, extending outwards. While these agricultural activities contribute some organic compounds to the air, the primary concern stems from the presence of industrial zones further inland, particularly those associated with phosphate processing and related industries. The city’s position within the wider Algerian coastal belt means it shares air quality challenges with other urban centers along this stretch, influenced by regional weather patterns and industrial emissions. The relatively narrow coastal plain limits the horizontal dispersion of pollutants, making Djendel’s air quality particularly sensitive to local emission sources and meteorological conditions.

Djendel’s air quality exhibits a distinct seasonal pattern dictated by the interplay of temperature, wind patterns, and humidity. The warm, dry months of summer (June-August) often see a build-up of pollutants due to reduced rainfall and stable atmospheric conditions. High temperatures can lead to increased photochemical smog formation, particularly when combined with emissions from vehicles and industry. Temperature inversions, common during this period, trap cooler air near the ground, preventing the vertical dispersion of pollutants. Conversely, the cooler, wetter months of autumn and winter (October-February) generally bring improved air quality. Increased rainfall helps to wash pollutants from the atmosphere, and stronger, more frequent winds facilitate their dispersal. However, periods of prolonged fog, particularly in November and December, can temporarily worsen air quality by trapping pollutants near the surface. Spring (March-May) presents a transitional period, with fluctuating wind patterns and increasing temperatures. Dust storms originating from the Sahara Desert can occasionally impact Djendel, contributing particulate matter to the air. Sensitive groups, including children, the elderly, and individuals with respiratory conditions, should exercise caution during the summer months, limiting outdoor activity during peak pollution hours. During periods of fog or dust storms, indoor air quality should also be prioritized, ensuring adequate ventilation and air filtration where possible. The transition seasons require vigilance, as unpredictable weather patterns can lead to sudden shifts in air quality.