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Baicheng occupies a distinctive position in the Songnen Plain of northeastern China's Jilin Province, situated at approximately 45.62°N latitude and 122.84°E longitude. This city of over 1.5 million residents lies at a modest elevation of around 150-200 meters above sea level, positioned strategically along the Nen River basin that flows through western Jilin. Baicheng's geography creates a unique urban-rural gradient where the compact urban core transitions rapidly into expansive agricultural lands, primarily dedicated to corn and soybean cultivation that dominates the surrounding Songnen Plain. The city's location places it within China's northeastern industrial belt, though it maintains a more agricultural character than many Jilin cities, with light manufacturing and food processing complementing its farming economy. Baicheng's terrain is predominantly flat with gentle undulations, lacking significant natural barriers that might otherwise help disperse pollutants. This flat topography, combined with the city's distance from major water bodies like the Sea of Japan (approximately 500 kilometers east), creates conditions where air masses can stagnate. The city's position in the continental interior means it experiences extreme temperature variations that significantly influence air quality patterns, with pollution often trapped during cold months when temperature inversions form over the flat plain. Urban expansion has created a distinct heat island effect that interacts with regional agricultural emissions, particularly during planting and harvest seasons when field burning occasionally occurs.

Baicheng's air quality follows a pronounced seasonal rhythm shaped by its continental climate and agricultural cycles. Winter (December-February) brings the most challenging conditions, as frigid temperatures from Siberian air masses create persistent temperature inversions that trap pollutants close to the ground. These cold-air inversions, combined with increased residential heating emissions and occasional agricultural residue burning, create hazy conditions that sensitive groups should monitor closely, limiting prolonged outdoor exposure during stagnant periods. Spring (March-May) begins with lingering winter pollution patterns but sees gradual improvement as temperatures rise and winds increase, though March and April can experience dust storms from the Mongolian Plateau that temporarily degrade air quality. Summer (June-August) offers the cleanest air, with monsoon-influenced southeasterly winds from the Pacific providing natural ventilation, frequent rainfall that scrubs pollutants from the atmosphere, and reduced heating emissions. This period represents the optimal time for outdoor activities, especially for children, elderly residents, and those with respiratory conditions. Autumn (September-November) begins with relatively good air quality but deteriorates as temperatures drop and agricultural burning increases during the October harvest season, creating episodic pollution events. The transition to winter heating in November further compounds this decline. Throughout the year, fog can exacerbate pollution visibility issues, particularly during temperature inversion conditions in late autumn and winter.