Rescal snow: Simulating snow dunes with cellular automata

When wind blows over dry snow, it creates shapes known as snow bedforms. These features, which include snow dunes, waves, snow-steps and sastrugi (Fig. 1), ornament Antarctica, Arctic sea ice, tundra, and mountain ridges (Filhol & Sturm, 2015; Kobayashi, 1980; Kochanski, Anderson, & Tucker, 2018). They change the reflectivity and average thermal conductivity of snow, and may change the patterns of snow accumulation and transport. Despite these effects, however, snow bedforms are poorly understood and not yet included in major snow or climate models.