Multiple portraits of dry snow avalanche slopes near villages in Nunavik, Canada

Population growth in Nunavik communities has led to new developments into active slope process areas. This study characterizes slopes favourable to dry snow avalanches in Nunavik. Avalanche-prone terrains, including release areas and avalanche tracks, cover 4.72 km2 in Umiujaq, 2.16 km2 in Salluit, 3.15 km2 in Kangiqsujuaq and 1.47 km2 in Kangiqsualujjuaq. Topographic and meteorological conditions associated with avalanche-prone slopes vary throughout Nunavik. Although avalanche slopes are predominantly associated with a concave profile, other profiles (e.g. linear, ‘hockey-stick’, stepped) and their occurrence vary greatly between study sites. The villages of Salluit, Kangiqsujuaq and Kangiqsualujjuaq share some similar characteristics, such as short slopes (22–222 m) and shorter runout distances (95–606 m), while the Umiujaq region stands out with higher values (slope: 69–344 m; runout: 172–933 m). Conditions favourable to snow transport, leading to overloading the snowpack and snow cornice formations, are more common at Umiujaq. The duration of the dry snow avalanche period varies by almost seven weeks between villages: the shortest is in Umiujaq (191 days) and the longest in Kangiqsujuaq (237 days). Finally, specific concerns are identified in each village, such as roads and buildings located in areas potentially affected by avalanches.