Minbya, nestled within Rakhine State, Myanmar, occupies a geographically significant position in the Kaladan River valley. Located at approximately 20.3622°N, 93.2733°E, the town’s terrain is largely flat, characteristic of the deltaic plains formed by the river’s deposition. The surrounding landscape is dominated by agricultural lands, primarily rice paddies, interspersed with pockets of mangrove forests closer to the Bay of Bengal, roughly 30km to the west. Minbya’s elevation is low, contributing to limited atmospheric dispersion of pollutants. The Kaladan River itself, a vital transportation artery, also influences local humidity and can contribute to localised fog formation. Unlike larger Myanmar cities with concentrated industrial zones, Minbya’s pollution sources are more diffuse, stemming from agricultural practices – including seasonal burning of rice stubble – and the use of biomass fuels for cooking and heating. The urban-rural gradient is relatively sharp; the town centre is compact, quickly transitioning to agricultural fields. This proximity to agricultural activity, combined with the flat topography and limited wind flow, creates conditions conducive to air quality challenges, particularly during the dry season. The regional climate is strongly influenced by the monsoon, dictating seasonal variations in air quality.

Minbya experiences a distinct wet and dry season, profoundly impacting air quality. The dry season, from November to April, is typically characterised by poorer air quality. Reduced rainfall means less atmospheric cleansing, and agricultural practices like post-harvest burning of rice straw release significant particulate matter. Temperature inversions, common during cooler nights in the dry season, trap pollutants near the ground, exacerbating the issue. February and March are often the most challenging months. Conversely, the wet season, from May to October, brings substantial improvements. Monsoon rains effectively wash away pollutants, and higher humidity reduces dust suspension. However, increased humidity can also foster mould growth, potentially impacting respiratory health. August and September, peak monsoon months, generally offer the best air quality. Fog, prevalent during the transition periods, can also temporarily reduce visibility and trap pollutants. Sensitive groups – children, the elderly, and those with pre-existing respiratory conditions – should limit outdoor exertion during the dry season and consider using masks when necessary. Monitoring local weather patterns and avoiding peak burning periods is crucial for protecting health.