Loading air quality context...

Tivaouane, nestled within the Thiès region of Senegal, occupies a geographically significant position in the country’s interior, approximately 120 kilometers northwest of Dakar. The city’s terrain is predominantly flat, characteristic of the Sahelian plain, with gentle undulations defining the surrounding landscape. This flatness, while facilitating urban expansion, can also contribute to localized air quality challenges, particularly concerning the dispersion of pollutants. Tivaouane sits at a relatively low elevation, around 25 meters above sea level, minimizing the natural vertical mixing of air. The city is not directly adjacent to a major body of water, though it benefits from proximity to the Fezzou River, which influences local humidity and microclimates. The surrounding area is a mosaic of agricultural land, primarily dedicated to peanut cultivation and millet farming, interspersed with sparse savanna vegetation. This agricultural activity, while vital to the regional economy, can introduce particulate matter into the air, especially during harvesting and land preparation. Further afield, the Thiès industrial belt, focused on groundnut processing and textiles, represents a potential source of industrial emissions. The urban–rural gradient around Tivaouane is gradual, with smaller villages and agricultural plots blending seamlessly into the urban fabric. This close integration of rural and urban activities means that agricultural practices and industrial processes directly impact the air quality experienced within the city limits, creating a complex interplay of factors influencing local atmospheric conditions.

Tivaouane’s air quality is dictated by its tropical savanna climate, exhibiting a distinct wet and dry season pattern. The dry season, typically spanning from November to May, presents the most significant air quality concerns. During these months, reduced rainfall and lower humidity lead to a build-up of dust and particulate matter, originating from agricultural activities, unpaved roads, and regional wind patterns. The lack of rainfall means there’s minimal atmospheric cleansing. Temperature inversions, common during the cooler nights of the dry season, trap pollutants close to the ground, exacerbating the issue. Wind patterns, often shifting and unpredictable, can either disperse pollutants or concentrate them in specific areas. The Harmattan wind, a dry and dusty trade wind blowing from the Sahara, frequently impacts Tivaouane during January and February, significantly degrading air quality. The wet season, from June to October, brings relief as increased rainfall washes away particulate matter and higher humidity helps to bind dust. However, periods of intense rainfall can also lead to flooding, which can release pollutants from stagnant water sources. Fog, though infrequent, can occur during the transition periods, trapping pollutants and reducing visibility. Sensitive groups, including children, the elderly, and individuals with respiratory conditions, should exercise caution during the dry season, particularly during periods of high dust concentration. Outdoor activities are generally more favourable during the wet season, although vigilance regarding potential flooding is advised.