Marovandrika, nestled within the Fianarantsoa region of Madagascar, presents a unique geographic context influencing its air quality. Situated at approximately -22.5191 latitude and 47.6665 longitude, the town occupies a highland plateau environment. The surrounding landscape is characterised by rolling hills and deeply incised valleys, typical of the central highlands of Madagascar. Elevation plays a crucial role; Marovandrika’s altitude contributes to cooler temperatures compared to coastal regions, but also fosters the potential for temperature inversions, trapping pollutants. The urban character is largely defined by a relatively sparse population of 13,000, with a strong agricultural base. Surrounding the town are extensive rice paddies and small-scale farming operations, contributing to particulate matter from land preparation and potential burning of agricultural waste. While not heavily industrialised, local brick-making and artisanal activities contribute to localised emissions. The urban-rural gradient is quite sharp, transitioning rapidly into forested areas and agricultural lands. Proximity to larger water bodies is limited, reducing the moderating influence of humidity on pollutant dispersion. The terrain’s complex topography hinders effective ventilation, exacerbating pollution concentrations during calm weather conditions. This combination of factors creates a localised air quality profile distinct from other parts of Madagascar.

Marovandrika experiences a distinct wet and dry season, profoundly impacting air quality. The dry season, roughly from April to October, sees a significant increase in particulate matter. This is due to increased dust from unpaved roads, agricultural activities like land clearing and burning for preparation, and reduced rainfall to wash pollutants from the atmosphere. September and October are typically the months with the poorest air quality. Temperature inversions are more frequent during the cooler nights of the dry season, trapping pollutants near ground level. The wet season, from November to March, brings relief. Heavy rainfall effectively scrubs the air, reducing particulate matter concentrations. However, increased humidity can promote mould growth, potentially impacting respiratory health. November and December often experience periods of dense fog, which, while visually striking, can trap pollutants. Sensitive groups – children, the elderly, and those with pre-existing respiratory conditions – should limit strenuous outdoor activity during the dry season, particularly in September and October. During the wet season, while overall air quality improves, monitoring for mould and dampness indoors is crucial. Wind patterns, generally easterly during the wet season and variable during the dry season, play a role in pollutant dispersion, but the surrounding topography limits their effectiveness.