Birnin Konni, nestled in the Tahoua region of Niger, occupies a geographically significant position within the Sahelian belt. Located at approximately 13.79°N, 5.26°E, the city’s terrain is predominantly characterized by undulating sandy plains and sparse vegetation, typical of this arid zone. The surrounding landscape is dominated by the Aïr Mountains to the north, providing a dramatic backdrop and influencing regional wind patterns, while the vast expanse of the Sahara Desert stretches eastward. Elevation is relatively low, averaging around 380 meters above sea level, contributing to a stable atmospheric layer that can trap pollutants under certain conditions. Birnin Konni’s proximity to agricultural zones, particularly those reliant on rain-fed farming, means that dust from cultivated fields and seasonal burning practices can significantly impact local air quality. The urban–rural gradient is sharp; the city transitions quickly into sparsely populated rural areas, with nomadic pastoralism a key feature of the surrounding environment. There are no significant bodies of water nearby, which limits natural air cleansing processes. While industrial activity is limited, the presence of local markets and vehicular traffic, coupled with the prevalence of wood-fired cooking stoves in many households, contribute to localized pollution sources. The city’s location within a broad, relatively flat plain means that wind dispersal of pollutants can be variable, depending on prevailing weather systems and the influence of the Aïr Mountains.

Birnin Konni’s air quality follows a distinct seasonal pattern dictated by the region’s arid climate. The dry season, spanning roughly from November to May, presents the most challenging conditions. Characterized by minimal rainfall and persistent sunshine, this period is prone to intense dust storms originating from the Sahara and surrounding agricultural lands. These storms, often exacerbated by strong Harmattan winds blowing from North Africa, dramatically reduce visibility and elevate particulate matter in the air. Temperature inversions, common during the cooler nights of December and January, can trap pollutants close to the ground, further worsening air quality. The Harmattan wind, while sometimes providing some dispersal, can also carry dust and pollutants from distant sources. The rainy season, from June to October, brings a temporary respite. Rainfall helps to settle dust and wash pollutants from the atmosphere. However, the onset of the monsoon season can also bring increased humidity and occasional localized flooding, which can release pollutants from stagnant water sources. The months of March, April, and May are particularly concerning due to a combination of increased agricultural activity (leading to burning) and the intensifying Harmattan winds. Sensitive groups, including children, the elderly, and individuals with respiratory conditions, should limit outdoor exposure during these periods and consider using face masks. During the rainy season, while overall air quality improves, vigilance regarding waterborne illnesses is crucial.