Loading air quality context...

Dieppe, New Brunswick, occupies a strategically important position within the Atlantic Canada region, nestled along the Northumberland Strait, a sub-basin of the Gulf of St. Lawrence. Its coordinates (46.0989, -64.7242) place it within a relatively low-lying coastal plain, characterized by gently rolling terrain and sandy soils. The city’s urban fabric extends from the shoreline, gradually transitioning into a mix of residential areas and light industrial zones. Dieppe’s proximity to the Bay of Fundy, renowned for its dramatic tidal range, influences local weather patterns and can impact air quality through sea breezes and fog formation. The surrounding landscape is predominantly rural, featuring agricultural lands – particularly potato farming, a significant regional industry – and interspersed with forested areas. This agricultural activity, while vital to the regional economy, can contribute to localized emissions of ammonia and particulate matter, especially during planting and harvesting seasons. To the west, the broader Moncton metropolitan area exerts an urban influence, while eastward, the landscape becomes increasingly rural and maritime. The urban–rural gradient is relatively smooth, with smaller villages and hamlets dotting the coastline. Elevation is minimal, rarely exceeding 50 meters above sea level, which can exacerbate the trapping of pollutants under certain meteorological conditions. The prevailing winds generally blow from the southwest, carrying air masses from across the Atlantic, but local topography and weather systems can significantly alter these patterns, impacting the dispersion of pollutants emitted within and around Dieppe.

Dieppe’s air quality experiences a distinct seasonal cycle heavily influenced by its maritime climate and agricultural practices. Spring (March-May) often brings a period of increased particulate matter due to agricultural activities like tilling and fertilizer application, combined with lingering fog that can trap pollutants close to the ground. The warming temperatures also increase volatile organic compound (VOC) emissions from vegetation. Summer (June-August) typically sees improved air quality due to stronger prevailing winds and increased mixing in the atmosphere, dispersing pollutants effectively. However, occasional heatwaves can lead to stagnant air and elevated ozone levels. Autumn (September-November) presents a mixed picture. While winds remain generally favourable, the harvest season can again contribute to particulate matter, and cooler temperatures can occasionally lead to temperature inversions, trapping pollutants near the surface. Winter (December-February) is often the most challenging period. Cold, stable air masses, coupled with frequent fog and temperature inversions, can significantly reduce air quality, particularly in the mornings. These inversions prevent vertical mixing, allowing pollutants from residential heating (wood stoves are common) and limited industrial sources to accumulate. Sensitive groups, including children, the elderly, and individuals with respiratory conditions, should limit prolonged outdoor exposure during these periods, especially on days with low visibility or a noticeable odour. Maintaining indoor air quality through proper ventilation and air filtration is also crucial during the winter months. The proximity to the Northumberland Strait can also introduce salt spray, impacting respiratory health, particularly for those with asthma.