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South Dumdum, situated in the Indian state of West Bengal within South Asia, occupies a strategic position in the Kolkata Metropolitan Area, approximately 10 kilometres north of Kolkata's city centre. This densely populated urban locale lies on the flat alluvial plains of the Ganges Delta, with an elevation averaging just 9 metres above sea level, making it inherently vulnerable to flooding. The city's geography is characterised by its proximity to the Hooghly River to the west and numerous smaller water bodies, which, while providing some natural ventilation, also contribute to high humidity that can trap pollutants. South Dumdum's urban character is defined by rapid, often unplanned development, transitioning from semi-rural to intensely urban, with a mix of residential, commercial, and transport infrastructure. Its location near Netaji Subhas Chandra Bose International Airport introduces significant aviation emissions, while its position within the broader Kolkata industrial belt—including nearby manufacturing and small-scale industries—exacerbates air quality challenges. The urban–rural gradient is steep, with surrounding agricultural zones to the north and east that occasionally contribute biomass burning, though urban sources dominate. The flat terrain inhibits natural dispersion of pollutants, while the city's dense built environment creates urban heat islands that worsen pollution episodes, particularly during calm winter conditions when temperature inversions are common.

South Dumdum's air quality follows a distinct seasonal pattern driven by its tropical wet-and-dry climate and local meteorological factors. During winter, from November to February, pollution peaks dramatically due to a combination of low temperatures, frequent temperature inversions, and calm winds that trap pollutants near the surface. This period sees heightened emissions from vehicle exhaust, construction dust, and waste burning, compounded by fog and haze that reduce visibility and increase particulate concentrations. Sensitive groups, such as children, the elderly, and those with respiratory conditions, should minimise outdoor activities during these months, especially in early mornings when inversions are strongest. The pre-monsoon season, from March to May, brings some relief through stronger winds and occasional nor'westers—violent thunderstorms that temporarily clear the air—though extreme heat can elevate ozone levels. The monsoon, from June to September, offers the cleanest air as heavy rainfall scrubs pollutants from the atmosphere and southwesterly winds disperse emissions, making this the best time for outdoor pursuits. Post-monsoon, from October onward, pollution begins to climb again as dry conditions return, with residents advised to monitor air quality forecasts and use protective masks during peak episodes.