Alauli, Bihar, situated at approximately 25.6440° N, 86.4065° E, occupies a geographically significant position within the fertile Gangetic plains of India. The town’s terrain is predominantly flat, characteristic of the Indo-Gangetic alluvial plain, resulting in minimal elevation changes. This flatness, while conducive to agriculture, presents challenges regarding air quality dispersion. Alauli lies within a region heavily reliant on agriculture, with surrounding landscapes dominated by rice paddies and other cultivated fields, contributing to seasonal biomass burning. The proximity to the Ganges River, though providing a vital water source, can also influence local weather patterns and, occasionally, trap pollutants under certain atmospheric conditions. Alauli’s location within Bihar places it within a broader industrial and agricultural belt, experiencing indirect impacts from larger urban centers and industrial zones further west. The urban–rural gradient around Alauli is gradual, with smaller villages and agricultural lands seamlessly blending into the town’s periphery. This close integration of rural and urban elements means agricultural practices, such as stubble burning after the harvest season, directly impact the town’s air quality. The flat topography limits natural ventilation, potentially leading to pollutant accumulation, especially during periods of stagnant air. The region's climate, characterized by hot summers and a distinct monsoon season, further complicates air quality dynamics, influencing both pollutant emissions and dispersion patterns. The soil composition, rich in alluvial deposits, also influences dust generation, a contributing factor to particulate matter pollution.

Alauli’s air quality experiences a distinct seasonal cycle heavily influenced by the region’s monsoonal climate. The pre-monsoon season (March-May) typically witnesses a significant deterioration in air quality, driven by rising temperatures and increased agricultural activity. Stubble burning, a common practice after the winter harvest, releases substantial quantities of particulate matter and other pollutants, creating hazy conditions and impacting visibility. The monsoon season (June-September) brings relief, with increased rainfall and wind speeds effectively flushing out pollutants. However, periods of low wind and heavy rainfall can still lead to localized humidity and the formation of ground-level ozone. The post-monsoon season (October-November) mirrors the pre-monsoon period, with a resurgence of agricultural burning and cooler temperatures that can trap pollutants near the ground, particularly during foggy mornings. Winter months (December-February) are generally characterized by colder temperatures and frequent fog, which significantly reduces air dispersion and exacerbates pollution levels. Sensitive groups, including children, the elderly, and individuals with respiratory conditions, should exercise caution during the pre-monsoon and post-monsoon seasons, limiting outdoor activities during peak pollution periods. The combination of temperature inversions, stagnant air, and agricultural emissions creates a challenging environment for air quality. During the monsoon, while overall air quality improves, individuals with allergies may experience increased pollen exposure. Maintaining indoor air quality through ventilation and air purification can be beneficial throughout the year, especially during periods of elevated pollution.