A helicopter-borne radar system for Canadian glacier mass assessment

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This project will fund the purchase of a custom-built helicopter radar system to image glacier ice up to 1km thick. Current mass estimates of Canadian glaciers are highly inaccurate due to widespread lack of ice thickness data, and modelling of glacier response to climate warming is significantly hindered by limited bed topography data. As such, our ability to predict sea-level contributions from Canadian glaciers, hazards from rapidly changing glaciers such as glacier lake outburst floods, downstream water resource availability, and the impact that changing glacier mass will have on Canadian mountain tourism, is limited. Current estimates of ice thickness and glacier bed topography have primarily been made using ground-based radar systems, which are towed on foot or by snowmachine and therefore limited in extent, highly time-consuming,  logistically expensive to obtain, and dangerous or impossible to operate in crevassed glacier regions. The proposed helicopter radar system will alleviate these problems, allowing for large-scale, safe data collection over ice masses in glacierized environments across Canada for the first time. This will facilitate the first accurate estimate of ice mass in the world's largest glaciated area outside of Greenland and Antarctica. A pilot helicopter radar system was tested in summer 2021 in the St. Elias Mountains, Yukon, with successful ice penetration depth up to 650m. The proposed system will build on this design with instrumentation to improve positioning accuracy, improved platform aerodynamics, better control and acquisition software, and radar developments to enable penetration of temperate (melting point) ice up to 1000m. The latter is necessary, as the sparse ground-based measurements suggest that most glaciers in the Yukon and Canadian High Arctic are considerably deeper than 650m. The primary research questions that will be addressed with data collected with the helicopter radar system are: 1) What is the mass of Canada's glaciers, on local, regional and national scales?; 2) What are the drivers of Canadian glacier flow rates in relation to subglacial topography and ice thickness?; 3) How will glacier mass and dynamics change in the future? High resolution helicopter radar surveys will be carried out in the first five years at major glaciers in the Yukon, Canadian High Arctic and British Columbia, where ice thickness data are currently lacking, to directly aid current funded research projects and provide crucial data for a wide variety of students supervised by team members. In the longer term (5-10 years), surveys will derive total glacial mass data for these three regions. The data gathered will benefit multiple collaborators, in addition to direct members of the project team, and provide globally important data required by organizations such as the World Glacier Monitoring Service (Switzerland), and the Intergovernmental Panel on Climate Change.