Compiling an Inventory of Historic Antarctic Aerial Photographs to Measure Long-Term Glacial Mass Balance Change from Digital Elevation Models

Long-term observations of glacier mass change provide a key indicator of atmospheric warming and are essential for understanding glacier behaviour and responses to climate forcing. Archived aerial photographs represent an underutilised source of historical information from which three-dimensional surface geometry can be reconstructed to quantify past glacier change. This approach is particularly valuable in Antarctica, where surface-elevation change prior to the 1990s remains poorly constrained due to limited pre-satellite altimetry and a scarcity of reliable Ground Control Points (GCPs). As a result, historic mass-balance estimates have largely relied on climate reanalysis and modelling.

Advances in photogrammetric techniques have substantially improved the efficiency and accuracy of Digital Elevation Models (DEMs) derived from historical aerial imagery. Here, we present a newly compiled inventory of Antarctic aerial surveys conducted throughout the twentieth century, documenting their spatial and temporal coverage to identify regions suitable for DEM reconstruction. Then, building on established workflows, we show newly constructed DEMs for three glaciers that formerly fed the Larsen A Ice Shelf on the Antarctic Peninsula, capturing surface geometry both before and after its collapse in 1995. These reconstructions reveal heterogenous glacier responses to reduced buttressing, controlled by local morphology and consistent with previous regional observations.