Snow Accumulation Monitoring using GNSS-Interferometric Reflectometry for Antarctica

Antarctica plays a central role in Earth's global climate system and stores most of the planet's freshwater. However, due to the continent's remoteness and extreme conditions, reliable in situ observations of snow accumulation remain rare. This gap in measurements makes it difficult to constrain ice sheet models and accurately project Antarctica's contribution to global sea level rise. In particular, regions such as the Totten Glacier in East Antarctica are of interest due to the significant mass loss since the 1990s, dominated by changes in coastal ice dynamics. In the context of Antarctica, GNSS Interferometric Reflectometry (GNSS-IR) presents an efficient and sustainable approach to monitor changes in snow accumulation with the potential to offer insights into regional surface mass balance models.

This contribution investigates a unique in situ dataset of six GNSS stations deployed on the Totten Glacier, operated seasonally between November 2016 and January 2019. These stations were originally designed to track ice motion, but they also capture reflections from the snow surface. By applying GNSS-IR, time series of snow accumulation are generated – once with the traditional retrieval approach using the gnssrefl software, and once by testing a novel machine learning-based retrieval framework. The derived snow accumulation time series are cross-referenced with outputs from regional surface mass balance models. The results provide insights into the spatio-temporal patterns of snow accumulation over the Totten Glacier and showcase the potential of GNSS-IR for environmental sensing.