Terrestrial glacier hazards in a changing climate

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Glaciers and ice sheets comprise three-quarters of Earth's fresh water, and harbour over 60 m of potential sea-level rise. In addition to contributing to the chronic hazards of sea-level rise and freshwater scarcity, mountain glaciers present acute hazards by impounding water behind unstable dams, debuttressing steep slopes and volcanic edifices, and rapidly advancing or collapsing during fast-flow events. Toward the long-term goal of understanding how climate-driven glacier change gives rise to glaciological hazards that affect over a billion people worldwide, the short-term objectives of the proposed research are to (1) model the mass balance and runoff from key areas in Canada's Arctic and sub-Arctic, (2) evaluate the environmental controls on glacier stability and complex glaciological hazards and (3) pursue a holistic understanding of glaciohydraulic hazards and a new approach to modelling them. Each objective will be tackled in multiple student projects. Objective 1 builds on over a decade of work at established field sites in southwest Yukon, where the icefields are among the largest current contributors to sea-level rise and glacier retreat has directly impacted local communities. It also extends our nascent modelling efforts in the Arctic to an important new site. Objective 2 springs from recent and startling observations that hint at a spectrum of unstable glacier behaviour, and investigates the direct and indirect controls of climate on glacier- and slope stability envelopes. Objective 3 recognizes the key role of hydraulic processes in nearly all glaciological hazards, and will take models of the glacier drainage system in fundamentally new directions. The proposed research involves theoretical and empirical approaches, with a field program targeting established sites in Canada's North and two new sites in the southern Coast Mountains. The research will be enriched by ongoing and emergent collaborations, as well as support through SFU's Centre for Natural Hazards Research. The anticipated impacts include (1) more precise quantification of glacier mass loss and runoff from two globally important glacierized regions of Canada, (2) deeper understanding of the fundamental drivers of glacier instability and complex hazards in mountain environments, (3) a new approach to understanding and modelling glaciohydraulic hazards and (4) training for 22 people over 5 years, in addition to northern students and community members. The proposed research addresses a wide range of existing and emerging terrestrial glacier hazards, against the complicated backdrop of climate change. These hazards affect indigenous and non-indigenous people in Canada, as well as those living in some of the most densely populated regions of the world. They also touch on Canada's water security, economic development and environmental resilience.