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Minamisuita, situated within Osaka Prefecture in Japan's Kansai region, occupies a strategic position in the densely urbanised Osaka Plain, bordered by the Yodo River to the north and Osaka Bay to the west. This ward of Osaka City lies at a low elevation of approximately 5-10 meters above sea level, characteristic of the alluvial plain formed by sediment deposits from surrounding rivers. The flat terrain, combined with proximity to Osaka Bay—just 5 kilometers west—creates a microclimate influenced by maritime breezes that can disperse pollutants but also foster humidity and occasional sea fog. Minamisuita is embedded within the Keihanshin Industrial Zone, one of Japan's major manufacturing and commercial hubs, with nearby areas hosting factories, ports, and transportation networks contributing to general urban pollution sources like vehicle emissions and industrial activity. The urban–rural gradient is steep, as Minamisuita transitions abruptly from high-density residential and commercial districts to more industrial zones near the bay, with limited green buffers. Surrounding landscapes include the Ikoma Mountains to the east, which can act as a barrier to wind flow, potentially trapping pollutants under certain meteorological conditions. This geographic setting, in a basin-like plain with industrial activity and high population density, exacerbates air quality challenges, particularly during stagnant weather patterns, making it a focal point for urban air management in East Asia.

In Minamisuita, air quality fluctuates seasonally due to meteorological factors and urban activity patterns. During winter (December to February), cold temperatures and frequent temperature inversions trap pollutants near the ground, leading to higher pollution levels, especially in January and February; sensitive groups like asthmatics should limit outdoor exertion on calm, foggy days. Spring (March to May) sees improvement as increasing winds and the end of heating season reduce emissions, with April and May offering favourable conditions for outdoor activities, though occasional pollen from surrounding areas may affect allergy sufferers. Summer (June to August) brings the East Asian monsoon, with heavy rainfall in June and July that scrubs pollutants from the air, resulting in cleaner conditions; however, high humidity and heat can exacerbate ozone formation on sunny days, so midday outdoor exercise is best avoided. Autumn (September to November) starts with residual summer rains but transitions to stable, dry weather by October and November, when pollution may rise due to reduced dispersion and increased vehicle use; this period requires vigilance for children and the elderly. Overall, peak pollution tends to occur in winter and late autumn, while the cleanest air is typically in summer during rainy spells, guiding residents to plan activities accordingly.