Relangi, Andhra Pradesh, nestled at approximately 16.7050° N, 81.6470° E, presents a compelling case study in the intersection of geography and air quality. Situated on the Coromandel Coast, Relangi’s location is intrinsically linked to the Bay of Bengal, influencing both its climate and pollution patterns. The town’s terrain is predominantly flat, characteristic of the fertile delta region formed by the Krishna and Godavari rivers, contributing to intensive agricultural activity in the surrounding areas. This agricultural zone, while vital for the regional economy, introduces sources of particulate matter, particularly during harvest seasons when crop residue burning is practiced. Relangi’s proximity to industrial belts further complicates the air quality picture; while not directly within a major industrial hub, it experiences downwind effects from facilities located further inland, particularly those involved in manufacturing and processing. The urban–rural gradient around Relangi is gradual, with small villages and agricultural fields transitioning seamlessly into the town’s built environment. The elevation is low, generally below 10 meters above sea level, which can exacerbate the trapping of pollutants, especially during periods of stagnant air. The coastal breeze, while generally beneficial in dispersing pollutants, can also carry marine aerosols and salt, impacting respiratory health. The surrounding landscape is dominated by rice paddies, coconut groves, and occasional clusters of mango orchards, all contributing to the region’s unique microclimate and influencing local air circulation patterns.

Relangi’s air quality follows a distinct seasonal cycle dictated by the region’s tropical climate and monsoon patterns. The pre-monsoon season (March-May) typically witnesses the poorest air quality. High temperatures and decreasing humidity create stable atmospheric conditions, often leading to temperature inversions where cooler air is trapped beneath a layer of warmer air, preventing vertical mixing and concentrating pollutants near the ground. Agricultural burning intensifies during this period, further degrading air quality. The monsoon season (June-September) brings relief, with strong winds and frequent rainfall effectively flushing out pollutants. However, heavy rainfall can also lead to increased humidity and the release of biogenic volatile organic compounds (BVOCs) from vegetation, which can contribute to ozone formation under certain conditions. Post-monsoon (October-November) sees a gradual return to drier conditions, with a resurgence of agricultural burning and a potential for stagnant air episodes. Winter months (December-February) are generally the most pleasant, with cooler temperatures and more frequent wind dispersal, though fog can occasionally form, trapping pollutants and reducing visibility. Sensitive groups, including children, the elderly, and individuals with respiratory conditions, should exercise caution during the pre-monsoon and post-monsoon seasons, limiting outdoor activity during peak pollution hours. Maintaining indoor air quality through ventilation and air purification can also be beneficial. Awareness campaigns promoting responsible agricultural practices and reducing industrial emissions are crucial for mitigating long-term air quality challenges.