Towards a New Regional Ice Thickness Dataset: UAV-Borne GPR for Quantifying Remaining Ice Volumes of Alpine Glaciers

Geophysical investigations of Alpine glaciers are essential for quantifying ice thickness and internal structures, yet traditional ground-based Ground-Penetrating Radar (GPR) remains logistically constrained in complex, high-altitude terrain. The emergence of Unoccupied Aerial Vehicle (UAV) platforms provides a transformative opportunity for radioglaciology, allowing for rapid, high-resolution data acquisition. While conventional mass balance methods focus on annual or subseasonal superficial mass changes, GPR enables the determination of the total remaining ice volume – a prerequisite for accurately forecasting future glacier evolution and glacial runoff. However, traditional ground-based GPR surveys are often logistically demanding and hazardous due to crevasses and unstable terrain, which frequently limit the spatial density and resolution of the resulting datasets. Recent advances in UAV technology have enabled the integration of lightweight geophysical sensors, offering a safer and more efficient alternative that significantly enhances spatial coverage and data resolution in glaciated environments.

This contribution presents results from ten glaciers in the Eastern Alps surveyed in 2024 and 2025 using a UAV-borne GPR system. The investigated sites range in size from 0.09 km² to 2.15 km² and encompass a diverse range of morphological types, including debris-covered, plateau, and valley glaciers. Furthermore, the study areas span contrasting geological settings and include both glaciers affected by anthropogenic activities (e.g., ski resort infrastructure) and largely undisturbed systems. Based on two years of UAV-based data acquisition, we provide a critical assessment of the associated methodological challenges, data quality limitations, and logistical constraints. We highlight key lessons learned regarding the performance of the UAV-borne GPR system in diverse cryospheric settings and outline future developments aimed at expanding this dataset to improve regional glacier volume estimates. Finally, we invite fellow researchers working with UAV-borne GPR to collaborate on establishing a new glacier thickness database.