Towards a portrait of avalanche hazard in Nunavik

• Main Authors: Saporiti, Chiara, Dias, Thomas, Morillon, Claire, Grenier, Jérémy, Bhiry, Najat, Decaulne, Armelle
• Other Authors: Université Paris 1 Panthéon-Sorbonne (UP1), Littoral, Environnement, Télédétection, Géomatique UMR 6554 (LETG), Université de Brest (UBO)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut de Géographie et d'Aménagement Régional de l'Université de Nantes (Nantes Univ - IGARUN), Nantes Université - pôle Humanités, Nantes Université (Nantes Univ)-Nantes Université (Nantes Univ)-Nantes Université - pôle Humanités, Nantes Université (Nantes Univ)-Nantes Université (Nantes Univ), Université de Strasbourg (UNISTRA), Université Jean Moulin - Lyon 3 (UJML), Université de Lyon, Université Laval Québec (ULaval), Centre d'Etudes Nordiques (CEN), Littoral, Environnement, Télédétection, Géomatique (LETG - Nantes ), Université de Brest (UBO)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Littoral, Environnement, Télédétection, Géomatique UMR 6554 (LETG), Nantes Université (Nantes Univ)-Nantes Université (Nantes Univ)-Centre National de la Recherche Scientifique (CNRS)-Institut de Géographie et d'Aménagement Régional de l'Université de Nantes (Nantes Univ - IGARUN), Labex DRIIHM, ANR-11-LABX-0010, LabEx DRIIHM, OHM Fessenheim, OHM Pays de Bitche, ANR-11-LABX-0010,DRIIHM / IRDHEI,Dispositif de recherche interdisciplinaire sur les Interactions Hommes-Milieux(2011)
• Format: Conference Object
• Language: English
• Published: HAL CCSD 2023
• Subjects: OHMi Nunavik; [SDE]Environmental Sciences; Crater Lake; Kangiqsualujjuaq; Nunavik; Umiujaq
• Online Access: https://hal.science/hal-04172178; https://hal.science/hal-04172178/document; https://hal.science/hal-04172178/file/Poster_avalanches_final.pdf; https://doi.org/10.34972/driihm-d269e2

International audience In Nunavik, the hilly territory of northern Quebec north of the 55th parallel, snow avalanches have only recently attracted scientific attention. The first reports followed the January 1, 1999 avalanche that killed nine people and injured 25 others in Kangiqsualujjuaq (northeast Nunavik). Since then, only a few studies have been carried out on snow and weather data related to this event. New data productions started in 2015-2016, when a team from OHMi Nunavik, interested in studying slope dynamics at different sites, recognized the geomorphological evidence of avalanches.To identify active avalanche paths, automatic time-lapse cameras (type ReconyxTM Hyper Fire2) were installed at the foot of several slopes. Operating year-round, and recording an hourly image of the slope during the day (between 9:00 am and 4:00 pm in most cases), the collection of images from these cameras led to the development of a first avalanche portrait at the scale of three Nunavik sites: Umiujaq, Wiyâshâkimî meteorite crater lake, and Kangiqsualujjuaq. Set up at different dates, the devices collected more than 40,000 images between 2017 and 2022. The avalanche deposits visible on these images enables to establish a winter and spring calendar of occurrence, to delimit their contours, to estimate their runout distances, and the weather conditions during the triggering phase. The Umiujaq site, which had not been identified as a potential avalanche site following the 1999 disaster in Kangiqsualujjuaq during a rapid study of villages in a likely vulnerable situation, is the one of the three study sites that has the most avalanches captured by our device. Au Nunavik, territoire vallonné du Québec nordique situé au nord du 55ème parallèle, les avalanches de neige n’ont que très récemment attiré l’attention des scientifiques. Les premiers rapports ont fait suite à la survenue de l’avalanche du 1er janvier 1999, qui a causé la mort de neuf personnes et blessé 25 autres à Kangiqsualujjuaq (Nunavik nord-est). Depuis, ...