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Donghua, situated within the rugged topography of Gansu province, rests at the intersection of the Loess Plateau and the diverse ecological zones of inland China. Positioned near coordinates 35.2167, 106.6000, the city is defined by its complex terrain, characterized by deep gullies, rolling hills, and arid landscapes typical of this high-altitude region. The urban character is deeply influenced by its position along the transition zone between agricultural plains and more mountainous, resource-rich territories. This unique geographical placement creates a distinct urban-rural gradient where industrial activity remains localized, yet the regional landscape plays a pivotal role in air quality management. The surrounding loess soil, which is inherently loose and prone to erosion, often contributes to airborne particulate matter during periods of high wind. Unlike coastal cities, Donghua lacks the moderating influence of large bodies of water, leading to a continental climate where temperature extremes are commonplace. The elevation—roughly 1,200 to 1,500 meters above sea level—further complicates atmospheric dispersion, as the surrounding topography can trap pollutants in valleys, particularly during calm weather conditions. Industrial belts situated on the periphery interact with the prevailing wind patterns, often channeling dust and combustion byproducts toward the urban core. As the city continues its development, the interplay between the harsh, dry terrain and the increasing density of local infrastructure remains a primary focus for environmental monitoring. Understanding this geographical context is essential for residents and planners alike, as the physical landscape serves as the primary determinant for the city's overall atmospheric health and long-term sustainability.

Donghua experiences a distinct four-season continental climate, significantly dictating its air quality trends throughout the year. Winter is the most challenging season, marked by frequent temperature inversions where cold, dense air remains trapped near the surface, preventing the dispersion of smoke from domestic heating and coal-reliant industrial activities. During these months, particularly December and January, sensitive groups should prioritize indoor activities and utilize air purifiers. As spring arrives, the regional climate shifts to become windier and drier. This is the period of the annual dust storms, where high-velocity winds carry fine loess particles from the arid northwest across the landscape, causing sharp spikes in particulate matter concentrations. April and May are often the most unpredictable months, requiring residents to monitor local atmospheric reports closely. Summer brings a welcome reprieve; the arrival of warmer air and sporadic rainfall helps to wash out pollutants, resulting in clearer skies and lower concentrations of suspended particles. Outdoor exercise is generally most favorable during the late summer, specifically August, when regional air circulation patterns are at their peak. However, as autumn transitions toward the colder months, a gradual decline in air quality is observed as heating systems begin operation and stagnant air masses return. November often signals the start of this transition, making it a critical period for health-conscious citizens to adjust their outdoor routines. By recognizing these seasonal rhythms—from winter inversions to spring dust events—residents can better manage their exposure, ensuring that outdoor engagement is balanced appropriately against the prevailing meteorological conditions of the Loess Plateau.