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Calgary is situated in the transition zone between the Canadian Prairies and the foothills of the Rocky Mountains, approximately 80 kilometres east of the mountain front. This unique positioning at an elevation of 1,045 metres above sea level creates a distinctive urban character where the city's skyline is dramatically framed by mountain vistas to the west. The Bow and Elbow Rivers converge within the city, flowing eastward through the urban core, providing natural corridors but also contributing to valley effects that can trap pollutants. Calgary's geography places it within Alberta's industrial belt, with oil and gas operations to the north and agricultural zones extending eastward across the prairies. The urban-rural gradient is sharply defined, with the city sprawling across relatively flat terrain that gives way abruptly to ranchlands and natural areas. This topography influences air quality through several mechanisms: the mountains to the west create rain shadows and can block weather systems, while the open plains to the east allow for unimpeded transport of pollutants from distant sources. The city's location in a river valley basin can exacerbate temperature inversions, particularly during winter months when cold air settles in low-lying areas. Proximity to the Rocky Mountains means Calgary experiences frequent chinook winds that can rapidly clear pollutants but also stir up dust. The Ottawa River reference appears to be an error—Calgary is far from this waterway, with its primary industrial emissions coming from local transportation, construction, and occasional wildfire smoke transported from British Columbia or northern Alberta forests.

Calgary's air quality follows a distinct seasonal pattern shaped by its continental climate and geographic setting. Winter months from December through February typically see the cleanest air, despite increased vehicle emissions during extreme cold spells, because frequent chinook winds and strong westerlies disperse pollutants effectively. However, during prolonged cold snaps, temperature inversions can trap vehicle exhaust and residential heating emissions in the river valleys, creating localized pollution pockets. Spring brings variable conditions—March and April experience dust storms as winds pick up dry soil from agricultural fields and construction sites, while May sees improving conditions as vegetation greens. The peak pollution months of June through August coincide with wildfire season, when smoke from British Columbia and northern Alberta forests can blanket the city for days or weeks, creating hazardous conditions. Summer also brings increased ozone formation from vehicle exhaust under intense sunlight, though afternoon thunderstorms occasionally provide cleansing. Autumn offers generally favourable conditions from September through November, with cooler temperatures reducing ozone formation and fewer wildfires, though early snowfalls can create slippery roads that increase braking-related particulate matter. Sensitive groups including those with respiratory conditions should monitor air quality alerts particularly during summer wildfire events and winter inversion periods, planning outdoor activities for mornings when pollution levels are typically lower. The city's elevation means UV radiation remains strong year-round, compounding respiratory irritation during high pollution episodes.