Frozen DunesTanner PierceAward: Top 100
School: minnetonka high school This photo captures a visually appealing example of Sastrugi, a demonstration of wind and snow erosion. It was taken at a high altitude, over a ridge, and where the wind was blowing in Snowbird, Utah. Sastrugi is the texture of snow that has been largely formed and eroded by wind. It forms as strong gusts of wind carry loose snow into a bump or something similar and applies a force to the ground, compressing the snow downwards. As this continues to happen, the wind gets diverted by the waves, further digging into the gaps and piling up into the drifts, making the ripples larger and easier to notice. When the snow is compressed, it can create densities of 400-500 kg/m³ which is significantly higher then regular snow (typically 100-300 kg/m³). Sastrugi is commonly rough-textured and forms in cold and snowy areas where the wind is naturally blowing. When the snow particles accumulate, they form lengthy and subtle "waves" that stretch as long or as short as the wind blows. You can find them anywhere from Antarctica to places like Colorado and Utah. Some even describe it as looking like dunes found in deserts. Sastrugi can be as short as 10 mm or even as tall as 5 feet. Overall, this phenomenon is a beautiful demonstration of the physics between snow and wind. 
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