Glacial lakes inventory and susceptibility assessment in the Alsek River Basin, Yukon, Canada

This study investigates glacial lake outburst floods (GLOFs) within the Alsek River Basin, Yukon, Canada, a region experiencing accelerated glacier retreat due to climate change. The formation and expansion of glacial lakes pose significant hazards to geomorphological and ecological systems, even in the absence of human infrastructure. Despite extensive research in other glaciated regions such as the Himalayas and Andes, the Canadian Cordillera remains understudied. This research aims to inventory glacial lakes and assess their susceptibility to GLOFs using remote sensing techniques and two distinct methodologies.

A total of 590 glacial lakes were identified, with 57 in direct or indirect contact with glaciers, warranting a detailed susceptibility assessment. The study applied the glacier-focused methodology of Wang et al. (Mt Res Dev 31(2):122 (2011). https://doi.org/10.1659/mrd-journal-d-10-00059.1) and the lakespecific dynamics approach of Khadka et al. (Front Earth Sci 8(January):1–16 (2021). https://doi.org/10.3389/feart.2020.601288). Key findings include: High-Hazard Lakes: Lakes 22, 23, 133, 134, and 275 were consistently identified as high-hazard due to factors such as large glacier inputs, steep moraine dams, and rapid expansion rates. GLOF Events: Four GLOF events were confirmed between 2017 and 2019, with the most significant reducing Lake 21's area by over 80%. Comparative Analysis: The integration of both methodologies provided a comprehensive understanding, revealing complementary insights into glacier-driven and lake-specific GLOF triggers.

The results underscore the critical role of glacier retreat and lake dynamics in driving GLOF hazards in the AlsekRiver Basin. The study highlights the importance of combining multiple assessment methodologies for robust hazard evaluation. Given the dynamic nature of glacial lakes and ongoing climate change, continuous monitoring and proactive hazard management strategies are essential to mitigate potential geomorphological and ecological impacts. This research contributes to the broader understanding of GLOFs in North America and underscores the need for similar assessments in other understudied glaciated regions.