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Cheria sits within the rugged landscapes of the Tébessa Province in northeastern Algeria, acting as a vital urban node amidst a transition from the high plateaus to the mountainous fringes of the Tell Atlas. The city is characterized by its undulating terrain, where elevation plays a critical role in atmospheric stability. Positioned far from the moderating influence of the Mediterranean coast, Cheria experiences a semi-arid continental climate that directly shapes its air quality profile. The surrounding landscape is a mosaic of agricultural zones and sparse scrubland, which contributes organic particulates during harvest seasons. Urban development is concentrated in a manner that creates a distinct urban-rural gradient, where the city center experiences higher densities of vehicular emissions compared to the airy periphery. The topography often traps pollutants within lower-lying areas, particularly during stagnant weather patterns, preventing the vertical dispersion of particulate matter. Because Cheria lies in a region prone to the influence of the Sahara to the south, it frequently serves as a corridor for mineral dust transport. The absence of large-scale heavy industrial belts within the immediate city limits means that the primary pollutants are predominantly combustion-based from transport and residential heating, alongside natural aeolian dust. This geographic positioning makes the city susceptible to atmospheric inversions, where a layer of warm air caps the cooler air below, concentrating pollutants near the ground and impacting the respiratory health of its inhabitants throughout the year.

In Cheria, air quality fluctuates through a distinct seasonal cycle driven by Mediterranean and Saharan influences. Winter brings the most significant challenges, as cold temperatures trigger a surge in residential biomass and fuel burning for heating. During these months, frequent temperature inversions trap smoke and nitrogen oxides near the surface, creating a dense haze that persists in the valley. Spring is characterized by the arrival of the Sirocco, hot, dry winds blowing from the Sahara that carry massive quantities of mineral dust. These events spike particulate matter levels, making the air gritty and hazardous for asthma sufferers. Summer typically sees a trough in anthropogenic pollution due to higher mixing heights and stronger convective currents that disperse pollutants, although extreme heat can increase ground-level ozone formation. Autumn serves as a transitional period, often marked by agricultural burning of crop residues in the surrounding plains, which releases plumes of organic carbon and smoke into the urban atmosphere. For sensitive groups, including children and the elderly, the winter heating peak and the spring dust storms are the most critical periods to limit outdoor exertion. Using air-filtering masks during Sirocco events and avoiding outdoor activities during early winter mornings when inversions are strongest is highly recommended. By monitoring the wind direction and temperature gradients, residents can better navigate the city's fluctuating atmospheric conditions, ensuring they avoid the peak pollution windows associated with these recurring meteorological phenomena across the region.