Osterhofen, nestled in the district of Landshut, Bavaria, occupies a geographically significant position within the Isar-Inn lowland, a gently sloping region characterized by fluvial terraces and fertile agricultural land. Situated at approximately 338 meters above sea level, the town benefits from a relatively mild climate influenced by its proximity to the Bavarian Forest to the southeast and the Danube River to the north. The surrounding landscape is predominantly rural, comprising extensive fields of barley, wheat, and maize, interspersed with pockets of woodland and meadows. Osterhofen’s location along the Isar River, a major tributary of the Danube, plays a crucial role in its microclimate and potential air quality dynamics. The river acts as a natural corridor, influencing local wind patterns and humidity levels. While Osterhofen itself is a relatively small town, it lies within commuting distance of Landshut and Munich, exposing it to potential impacts from regional industrial activity and traffic emissions. The urban–rural gradient is gradual; the town seamlessly blends into the agricultural landscape, minimizing the sharp contrasts often seen in larger metropolitan areas. The terrain, being largely flat, can contribute to the stagnation of air pollutants under certain meteorological conditions, particularly during periods of temperature inversion. The absence of significant topographical barriers means that pollutants can spread relatively easily across the region, making regional air quality management strategies essential. Agricultural practices, including fertilizer use and livestock farming, also contribute to localized air quality concerns, particularly concerning ammonia emissions.

Osterhofen’s air quality experiences a distinct seasonal cycle heavily influenced by meteorological patterns. Spring (March-May) often brings a gradual improvement as temperatures rise and wind speeds increase, dispersing accumulated pollutants. However, agricultural activities intensify during this period, leading to elevated ammonia levels from fertilizer application and livestock operations, impacting local air quality. Summer (June-August) typically sees relatively good air quality due to consistent sunshine, higher temperatures, and frequent convective mixing, which effectively ventilates the atmosphere. However, heatwaves can lead to stagnant air and ozone formation, particularly during periods of prolonged sunshine. Autumn (September-November) presents a more complex picture. While wind speeds generally remain moderate, temperature inversions become more frequent, trapping pollutants near the ground, especially in the mornings. Agricultural burning, though regulated, can also contribute to particulate matter pollution. Winter (December-February) often witnesses the poorest air quality. Cold, stable air masses, coupled with frequent temperature inversions, lead to pollutant accumulation. Fog, common during this season, further exacerbates the problem by trapping pollutants close to the ground. Sensitive groups, including children, the elderly, and individuals with respiratory conditions, should limit prolonged outdoor activity during these periods, particularly on days with low visibility or a noticeable odour. Maintaining indoor air quality through proper ventilation and air purification can also be beneficial. The interplay of agricultural practices, regional traffic, and local weather patterns dictates the overall air quality experience throughout the year in Osterhofen.