Surface Mass Balance of the Antarctic Megadune Plateau

The East Antarctic Plateau contains particular areas with megadunes and wind-glazed surfaces, exhibiting distinct patterns of snow accumulation and its variability over time and space. Despite its significance for sea levels, ocean circulation, and weather patterns, knowledge about snow accumulation in these areas remains limited. Several ice cores, coming from diffrent parts of Plateau, were drilled during the East Antarctic International Traverse (EAIIST).

Using volcanic horizons as time markers, coupled with ground-penetrating radar (GPR) measurements, we intend to reconstruct the surface mass balance (SMB) of the megadune plateau in both time and space for the last ca. 2000 years where accumulation is largely unknown. In a first step, geochemical profiles of the different cores were analyzed. A critical analysis is first conducted to find the best marker of the volcanic eruptions between the electrical conductivity, the total sulfur concentration and the sulfate profile. Based on this critical analysis, a common volcanic-dating scale is proposed for the different drilling sites. However, the megadune areas show a strong disturbed layering accumulation with clearly visible ablated layers, making the volcanic identification a true challenge.  Work is currently underway to use volcanic cryptotephra and electron microprobe analysis to unambiguous determine the volcanic tie-point identification. In a subsequent step, GPR data will be process to spatialize the accumulation information. Matching radar internal layers with well-dated ice core reference layers will allow for dating and deducing the surface mass balance over time for the entire EAIIST transect.