Consensus-Based Rock Glacier Inventorying in the Torngat Mountains, Northern Labrador

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The Torngat Mountains of northern Labrador are an Arctic cordilleran mountain range located at the southern limit of the Canadian Arctic. Sparse observations of periglacial landforms including rock glaciers and ice-cored moraines imply that permafrost may be widespread, but limited in situ information is available for the region. In this study, we provide the first comprehensive feature inventory of intact rock glaciers in the Torngat Mountains of northeast Canada. Prospective features were identified by a team of eight independent mappers using high-resolution satellite imagery. The initial inventory was re-assessed via consensus-building and review stages, resulting in a final inventory of 608 rock glaciers. Rock glaciers were distributed from ~58°N to ~60°N and were primarily concentrated in the northern end of the Torngat Mountains National Park with southern clusters located in high relief coastal mountains near 59°N. The use of a large mapping team and the multistage consensus-based approach maximized feature inclusion and reduced misinterpretation of other features (e.g., debris-covered glaciers, ice-cored moraines, and talus couloirs) for rock glaciers. Our results show the efficacy of consensus-based landform identification for geomorphological mapping in the heterogeneous environment of the Torngat Mountains.