Mangalore, situated along the Arabian Sea coast in Karnataka's Dakshina Kannada district, occupies a strategic position at the confluence of the Netravati and Gurupura rivers, creating a distinctive estuarine landscape that profoundly influences its air quality dynamics. The city's topography features undulating laterite hills and valleys, with elevations ranging from sea level to approximately 22 meters, creating natural basins that can trap pollutants during certain meteorological conditions. Mangalore serves as Karnataka's primary port city and industrial hub, with the New Mangalore Port handling substantial cargo traffic whose emissions directly impact coastal air quality. The city's urban character blends dense commercial zones along National Highway 66 with residential areas spreading across hillsides, creating an urban-rural gradient where pollution disperses unevenly. Surrounding the urban core are cashew plantations, coconut groves, and paddy fields that typically act as pollution sinks but can contribute agricultural burning residues seasonally. The Western Ghats mountain range lies approximately 60 kilometers east, creating a rain shadow effect that influences wind patterns and pollution transport. Mangalore's coastal location subjects it to sea breezes that generally improve air quality by dispersing pollutants inland, but during winter months, these same breezes can transport marine emissions and industrial pollutants from the port and industrial belt—including the MRPL refinery and BASF chemical plant—back toward residential areas. The city's position within the narrow coastal plain between the Arabian Sea and Western Ghats creates a corridor effect where pollutants from vehicles on NH-66, construction dust from ongoing infrastructure projects, and industrial emissions accumulate during periods of atmospheric stability.

Mangalore's tropical monsoon climate creates distinct seasonal air quality patterns driven by alternating wet and dry periods. During the southwest monsoon season from June to September, heavy rainfall acts as a natural air purifier, washing particulate matter from the atmosphere and significantly improving air quality—these months offer the best conditions for outdoor activities despite high humidity. The post-monsoon period from October to November brings transitional weather with moderate pollution levels as construction activities resume and vehicle traffic increases after the rains. December through March represents the peak pollution season when dry northeast monsoon winds create stable atmospheric conditions with frequent temperature inversions that trap pollutants close to the ground. During these winter months, cool nighttime temperatures combine with morning fog to form haze that mixes with emissions from port operations, fishing boats, vehicular exhaust, and road dust—creating persistent poor air quality episodes. Sensitive groups including children, elderly residents, and those with respiratory conditions should limit outdoor exposure during morning hours in these months when pollution concentrations peak. April and May bring pre-monsoon heat with sea breezes that provide some dispersion relief, though higher temperatures can accelerate photochemical reactions that generate secondary pollutants. The seasonal cycle demonstrates how Mangalore's coastal monsoon climate creates a natural cleansing mechanism during rainy months but allows pollution accumulation during the dry winter period when atmospheric mixing is minimal.