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Chengguan, situated in Henan Province's central plains of East China, occupies a strategic position within the North China Plain—one of China's most densely populated and industrially active regions. The city's coordinates at 35.4623°N, 113.8054°E place it approximately 100 kilometers north of the Yellow River, with an elevation around 100 meters above sea level, characteristic of the flat alluvial terrain that defines this agricultural heartland. This low-lying topography creates natural basins that trap air pollutants, particularly during stable atmospheric conditions. Chengguan functions as an urban core within a broader rural-urban gradient, surrounded by extensive wheat and corn fields that contribute seasonal agricultural burning emissions. The city lies within Henan's industrial corridor, where manufacturing, coal-based energy production, and transportation networks generate consistent anthropogenic pollution. Proximity to major cities like Zhengzhou (150 km southeast) and Anyang (80 km north) means regional pollution transport significantly impacts local air quality, especially when prevailing winds carry industrial plumes across the plain. The absence of significant water bodies or mountainous barriers allows pollutants to accumulate with minimal natural dispersion, making geographic context a critical determinant of Chengguan's air quality challenges.

Chengguan experiences distinct seasonal air quality patterns shaped by the East Asian monsoon and regional meteorological conditions. Winter (December-February) brings the worst pollution, with frequent temperature inversions trapping particulate matter from heating emissions and industrial activity, particularly in January when coal combustion peaks. Sensitive groups should minimize outdoor exposure during these stagnant periods. Spring (March-May) sees gradual improvement as increasing winds disperse pollutants, though March-April may experience dust storms from the northwest, temporarily elevating coarse particle levels. Summer (June-August) offers the cleanest air, with monsoon rains from the southeast scrubbing pollutants and stronger vertical mixing preventing accumulation; July-August are optimal for outdoor activities. Autumn (September-November) begins with relatively good conditions but deteriorates by late October as heating season commences and atmospheric stability increases, creating haze episodes. Throughout the year, calm winds and fog—common in the North China Plain—exacerbate pollution by reducing dispersion. Residents should monitor local air quality forecasts, with sensitive individuals using N95 masks during peak pollution months and planning outdoor exercise for summer mornings when ozone levels are lowest.