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Yueyang occupies a strategic position in northeastern Hunan province, situated on the southeastern shore of Dongting Lake where the Yangtze River meets the Xiang River. This location at 29.3647°N, 113.1309°E places the city within China's Yangtze River Economic Belt, approximately 150 kilometers north of Changsha. The urban area sits at a modest elevation of 30-50 meters above sea level, with terrain transitioning from the flat alluvial plains of the lake basin to gently rolling hills to the east and south. Dongting Lake, China's second-largest freshwater lake, creates a significant water body that influences local microclimates while also serving as a crucial agricultural and fishing resource. The city's geography creates a distinctive urban-rural gradient where dense urban development along the waterfront gives way to extensive rice paddies, aquaculture ponds, and vegetable farms in the surrounding countryside. This positioning makes Yueyang vulnerable to air quality issues as pollutants from urban transportation, residential heating, and small-scale manufacturing can become trapped by the surrounding topography. The lake's evaporative effects contribute to humidity that can exacerbate particulate matter accumulation, while the city's location downwind of industrial zones in Hubei province means it occasionally receives transported pollution from northern regions. The urban heat island effect in Yueyang's core further complicates atmospheric mixing, particularly during stable weather conditions.

Yueyang experiences distinct seasonal air quality patterns shaped by the East Asian monsoon system and local geographic factors. During winter (December-February), cold air masses from the north bring stable atmospheric conditions with frequent temperature inversions that trap pollutants near the surface. Residential heating demands increase particulate emissions, making January typically the most polluted month when visibility can be severely reduced by haze. Sensitive groups should limit prolonged outdoor exposure during these months. Spring (March-May) brings transitional weather with increasing rainfall that helps cleanse the atmosphere, though occasional dust events from northern China can temporarily degrade air quality. The period from late April through May generally offers improving conditions. Summer (June-August) features the southeast monsoon with higher temperatures, increased convection, and frequent precipitation that effectively disperses pollutants, making July and August the cleanest months for outdoor activities. However, high humidity can combine with ozone precursors to create occasional smog episodes. Autumn (September-November) sees gradually deteriorating conditions as monsoon winds weaken and atmospheric stability increases, with October often marking the transition toward winter pollution patterns. Throughout the year, morning fog is common due to the lake's influence, which can temporarily trap pollutants until daytime heating improves vertical mixing. Wind patterns are generally light except during frontal passages, contributing to the accumulation of locally generated pollution.