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Narayanganj, situated within Bangladesh's densely populated Dhaka Division, occupies a strategic position just 16 kilometers southeast of the capital Dhaka along the banks of the Shitalakshya River, a distributary of the mighty Brahmaputra. This city of approximately 1.5 million people lies within the vast Ganges-Brahmaputra delta, characterized by flat alluvial plains with elevations rarely exceeding 10 meters above sea level, creating a landscape inherently prone to waterlogging and stagnant air conditions. Narayanganj's geography places it at the heart of Bangladesh's industrial belt, with its riverfront location historically making it the country's premier jute processing center and now a hub for textile and dyeing factories that cluster along waterways. The city's urban fabric blends densely packed residential areas with sprawling industrial zones, particularly along riverbanks where emissions from factories and vessels concentrate. Proximity to the Buriganga River system and numerous canals creates a humid microclimate that traps pollutants, while the flat terrain prevents natural ventilation, allowing industrial emissions, brick kiln smoke from surrounding peri-urban areas, and road dust to accumulate rather than disperse. This urban-rural gradient sees pollution sources intensify toward the city core, where narrow streets and high building density further inhibit air circulation. Narayanganj's position within the greater Dhaka megacity region means it both contributes to and receives transboundary pollution from the capital's vehicular and industrial activities, creating a compounded air quality challenge exacerbated by its low-lying riverine geography.

Narayanganj's tropical wet-and-dry climate creates distinct seasonal air quality patterns driven by monsoon rhythms and temperature variations. During the dry winter months from November through February, pollution peaks dramatically as cool temperatures combine with frequent temperature inversions that trap pollutants near the ground, while low wind speeds from the northeast allow emissions from brick kilns, factories, and vehicles to accumulate. This period sees thick morning fog mix with smoke and dust, creating hazardous haze particularly harmful for children, elderly residents, and those with respiratory conditions who should limit outdoor activities, especially during early mornings when inversion layers are strongest. The pre-monsoon hot season from March to May brings rising temperatures that increase photochemical reactions, though occasional thunderstorms provide temporary cleansing; sensitive groups should remain hydrated and avoid midday exertion when ozone levels may rise. The monsoon season from June to September offers the cleanest air as southwest winds bring heavy rainfall that scrubs pollutants from the atmosphere, with July and August being optimal for outdoor activities despite high humidity. The post-monsoon transition in October sees deteriorating conditions as rains cease and pollution sources reactivate, signaling the approach of the hazardous winter period. Throughout the year, river vessel emissions remain constant, but their impact varies with seasonal wind patterns that either disperse or concentrate these pollutants over the city's low-lying landscape.