Tracking river course dynamics in Alpine glacier forelands with satellite time series

Satellite imagery time series (SITS) have become a powerful tool to monitor changes within complex landscapes. Opposed to single snapshots, insights and information derived from SITS expand our knowledge about dynamic processes, such as those occurring in glacier forefields. In recent decades, the decline of glaciers and the related enlargement of glacier forefields have occurred at unprecedented rates, leading to the evolution of new landscapes. For instance, climate change has accelerated the meltwater runoff from glaciers, resulting in the emergence and expansion of drainage systems. This work aims at a spatio-temporal analysis of the evolution of proglacial river courses in glacier forelands for selected areas in the High Tauern mountain range and the Ötztal Alps in Austria. For this purpose, on-demand data cubes based on high-resolution SITS from PlanetScope are created for the focus areas. A machine learning classification of distinct land cover types, focusing on water detection is performed to identify the river course at each timestamp. Ancillary data, such as topography, is integrated into the classification process to enhance accuracy. Further, an analysis of time series trajectories allows the quantification of change per pixel, providing a detailed overview of the evolution of the river courses. These changes are then related to deglaciation processes driven by climatic variations. The results of this study will contribute to a better understanding of how glacier retreat influences hydrological systems in alpine environments, offering valuable insights for future research and environmental management.