Change in snow distribution patterns over an Antarctic ice floe following a snow storm event
Sea ice, snow and atmosphere interactions are major drivers of the spatial distribution of snow over sea ice in polar regions. Here, we quantify changes caused by a snow storm in the spatial distribution of snow over an Antarctic ice floe at resolutions of 1-10 cm and over 100 m x 100 m. The snow/ice elevations were obtained using a Terrestrial Laser Scanner during the SIPEX-2 in 2012. The pre-storm surface (2012-10-20) exhibits multi-directional elongated snow dunes behind aerodynamic obstacles likely formed during previous snow storms. The post-storm surface (2012-10-23) exhibits clear new deposition dunes elongated along the predominant wind direction. The new deposition areas amount to 38% of the total surveyed area. Patterns of erosion are less evident but cover a larger portion of the area. This results in a total volume of change near zero with a mean elevation difference of 0.02 m. After the storm, the statistical distributions of elevation and the 2D correlation functions remain similar to those of the pre-storm surface. The pre- and post-storm surfaces also exhibit power-law relationships in the power spectrum with little change between pre- and post-storm slopes. These observations suggest that despite the significant change observed in the snow surface patterns, the change does not translate into significant changes in the spatial statistical and scaling properties of the surface morphology. Such an observation is important for sea-ice model representations of the sub-pixel variability of sea ice surfaces, particularly between snow storm events, although more datasets will be required to extend these results to a wider range of sea ice surface morphologies.