Beharona, a small city nestled within the Toliara Province of Madagascar, occupies a unique geographic position. Located at approximately -21.5214 latitude and 44.3046 longitude, the city sits relatively close to the coast, though shielded somewhat by the broader landscape. The terrain is characterised by a gently undulating plateau transitioning into drier, spiny forest ecosystems further inland. This region of southwestern Madagascar is known for its semi-arid climate and distinctive flora. Beharona’s elevation is modest, contributing to relatively stable atmospheric conditions. The surrounding landscape is predominantly agricultural, with subsistence farming and some pastoral activity being the dominant land uses. While not a major industrial hub, localised brick-making and small-scale processing of agricultural products contribute to particulate matter emissions. The urban-rural gradient is quite sharp; Beharona itself is a concentrated settlement surrounded by sparsely populated rural areas. This proximity to agricultural lands means seasonal burning for land preparation is a significant factor. The coastal influence brings breezes, but these can be inconsistent, and the lack of significant topographical barriers allows pollutants to accumulate, particularly during calmer periods. The city’s location downwind of prevailing winds from agricultural areas exacerbates this issue, impacting local air quality.

Beharona experiences a distinct wet and dry season, heavily influencing its air quality. The dry season, roughly from April to November, is characterised by consistently high temperatures and minimal rainfall. This period sees a peak in particulate matter pollution, largely due to increased dust from unpaved roads and widespread agricultural burning to clear land for the next planting season. Winds, though present, are often not strong enough to fully disperse the smoke and dust, leading to stagnant air conditions. November marks the transition, with sporadic rainfall beginning to settle dust. The wet season, from December to March, brings relief. Frequent rainfall effectively washes away particulate matter, resulting in significantly improved air quality. However, increased humidity can promote mold growth, potentially impacting respiratory health. Temperature inversions, while not as pronounced as in temperate climates, can still occur during the cooler nights of the dry season, trapping pollutants near ground level. Sensitive individuals – children, the elderly, and those with pre-existing respiratory conditions – should limit strenuous outdoor activity during the peak of the dry season (July-September). The months of January and February, during the heaviest rainfall, generally offer the most favourable conditions for outdoor pursuits.