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Daloa, situated in west-central Ivory Coast's Sassandra-Marahoué District, occupies a strategic position as a major crossroads city connecting the coastal economic hubs with the country's interior agricultural heartlands. Nestled at approximately 250 meters above sea level on the Guinea Highlands plateau, its terrain features gently rolling hills interspersed with savanna woodlands, creating a natural basin effect that can trap pollutants under certain meteorological conditions. The city lies roughly 150 kilometers inland from the Atlantic coast, with no major rivers or significant water bodies immediately adjacent to the urban core, though the Sassandra River flows approximately 50 kilometers to the west. This inland location shields Daloa from direct maritime influences while placing it squarely within Ivory Coast's cocoa and coffee belt, where agricultural burning during land preparation seasons contributes significantly to regional particulate matter. The urban-rural gradient is sharply defined, with Daloa serving as a bustling commercial center surrounded by extensive farming communities, creating a distinctive pollution profile where urban emissions from transportation and residential fuel combustion blend with agricultural haze. The city's position along major transport corridors linking Abidjan to northern regions ensures constant vehicular traffic, while its role as a regional market hub concentrates commercial activity in dense urban quarters where ventilation can be limited by surrounding topography.

Daloa experiences two distinct seasons that dramatically influence air quality patterns throughout the year. During the long dry season from November to March, northeasterly Harmattan winds transport vast quantities of dust from the Sahara Desert across West Africa, creating persistent haze that significantly reduces visibility and elevates particulate matter concentrations, particularly from December through February. This period represents the peak pollution months when sensitive individuals should limit prolonged outdoor exposure and consider protective masks during dust events. The transition to the rainy season from April to October brings relief as frequent downpours effectively wash pollutants from the atmosphere, with June through August offering the cleanest air conditions ideal for outdoor activities. However, the early rainy months of April and May can see increased biomass burning as farmers clear land before planting, creating temporary smoke plumes that drift into urban areas under variable wind patterns. Temperature inversions occasionally develop during cool, calm nights in the dry season, trapping vehicle emissions and residential smoke near ground level until morning breezes disperse them. The monsoon circulation from the southwest during rainy months provides consistent ventilation, while the absence of significant fog or temperature extremes prevents the severe pollution episodes seen in some global cities. Health guidance emphasizes monitoring local visibility during Harmattan season and planning strenuous activities for morning hours when pollution dispersion is typically better.