Kluane National Park Helicopter-borne ice penetrating radar data, 2023-2025

In the past, when Earths temperature was as warm as today, the global sea level was 7-9 m higher. The Western Antarctic ice sheet is likely the source of this past rise, but there is uncertainty about how quickly it will accelerate. Glacier motion and mass loss are largely controlled in an unobservable environment where the ice interacts with the ground, underscoring the need for accurate glacier-geometry models as baseline data. Accessible mountain glaciers can provide insight here while also being a critically threatened water resource, for drinking water, ecosystem health and crop irrigation.Helicopter-borne ice-penetrating radar surveys of the nine largest glaciers in Kluane National Park were completed to characterize the ice thickness and bed topography of this crucial area. Before these surveys, no regional-scale ice thickness measurements of these glaciers existed. Eight of the nine surveyed glaciers are surge-type glaciers; remaining relatively still for years (called quiescence) and then increasing in velocity by an order of magnitude for 1-2 years (called surging) before returning to quiescence. Interactions at the glacier bed largely control the internal dynamics that produce this behaviour. Characterizing the bed topography of all the surge-type glaciers in the park provides critical context for understanding these behaviours and interactions. These surveys were completed simultaneously with airborne photogrammetry surveys, comprising a complete collection of ice thickness and surface elevation data. The surveys were designed to collect cross-glacier transects at 1 km spacing to optimize the ability to process these data with surface elevation models for the creation of bed topography data. Using this data in concert with high-resolution observations of the glacier's surface, we intend to create three-dimensional geometry models for every major glacier in the park.