ALBERT

Description: Snow cover affects the variability of the physical properties of sea ice. The snow’s unique thermal and optical properties govern the mass and energy fluxes in the sea ice system. They are important for sea ice evolution, energy exchanges between the ocean and the atmosphere, and light availability for ecosystems below the sea ice. Furthermore, snow significantly impacts remote sensing retrievals, especially for sea ice thickness. Yet, data on the physical properties of snow and its effects on sea ice are extremely limited, especially in Antarctica. This leads to large uncertainties in the coupling of climate feedback and results in significant biases in model representations of the sea ice cover. During our field campaign from October-December 2022 in McMurdo Sound, we quantitatively investigated the physical properties of snow on Antarctic sea ice, following the same protocols used during the MOSAiC expedition. The season’s unique sea ice conditions provided the ideal laboratory to study a range of snow conditions and to differentiate between sea ice and snow drivers for the atmosphere-sea ice-ocean system. Our set of snow measurements on sea ice, unprecedented in Antarctica, includes ground snow/ice measurements, automatic weather and radiation stations, and drone-based measurements. These extensive measurements made it possible to capture the physical properties of snow and their spatial variability and simultaneously measure the different components of the energy balance at varying spatial scales. We will use this dataset to improve our understanding of snow's role in the Antarctic sea ice system.