Chantal, nestled in Haiti’s Sud department, occupies a geographically complex position within the country’s southern peninsula. Located at approximately 18.2017° N, 73.8896° W, the city’s terrain is characterized by rolling hills and valleys, typical of the region’s transition zone between the central plateau and the coastal plains. The elevation, while not dramatically high, contributes to localized microclimates and potential for temperature inversions, impacting air circulation. Chantal’s proximity to the Caribbean Sea, roughly 15-20 kilometers to the south, introduces a maritime influence, moderating temperatures but also potentially carrying marine aerosols and salt spray. The surrounding landscape is a mosaic of small-scale agriculture – primarily sugarcane and bananas – interspersed with patches of dry forest and scrubland. This agricultural activity, while vital to the local economy, can be a source of particulate matter, particularly during harvesting and burning seasons. The urban–rural gradient around Chantal is relatively sharp; the city itself is a small, concentrated settlement, quickly giving way to rural agricultural lands. There are no major industrial belts immediately adjacent to Chantal, but the broader Sud department experiences some light processing of agricultural products, which could contribute to localized air pollution. The prevailing winds generally flow from the east to the west, influenced by the trade winds, which can disperse pollutants but also concentrate them in certain areas depending on topography. The region's geology, with underlying limestone formations, can also influence the dispersion of airborne particles.

Chantal’s tropical climate dictates a wet and dry season pattern, significantly influencing air quality dynamics. The wet season, typically spanning from April to October, brings frequent rainfall and increased humidity. While rain naturally helps to cleanse the atmosphere by scavenging pollutants, the preceding dry period often leads to a build-up of particulate matter. During the dry season (November to March), reduced rainfall and lower humidity create conditions conducive to dust accumulation from agricultural activities and unpaved roads. Temperature inversions, where cooler air is trapped beneath a layer of warmer air, are more common during the cooler months (December-February), hindering vertical mixing and trapping pollutants near the ground. Wind patterns also play a crucial role; periods of calm winds exacerbate pollution, while stronger easterly trade winds can provide some relief. The burning of agricultural waste, a common practice after harvests, is a significant contributor to air pollution during the transition months (March and November). Sensitive groups, including children, the elderly, and individuals with respiratory conditions, should exercise caution during the dry season and periods of stagnant air. Outdoor activities are generally more favorable during the wetter months, although heavy downpours can temporarily reduce visibility. Fog, though infrequent, can also trap pollutants, creating localized air quality concerns. The intensity of agricultural burning directly impacts air quality, making the months surrounding the harvest periods particularly challenging for respiratory health.