Wind-packing of snow: How do wind crusts form? ...

• Main Author: Sommer, Christian Gabriel
• Format: Doctoral or Postdoctoral Thesis
• Language: English
• Published: Lausanne, EPFL 2018
• Subjects: snow; hardness; wind-packing; wind crust; wind slab; saltation; erosion; deposition; wind exposure; Antarctica; Antarc*
• Online Access: https://dx.doi.org/10.5075/epfl-thesis-8628; https://infoscience.epfl.ch/handle/20.500.14299/149652

Wind-packing of snow is the process responsible for the formation of wind slabs and wind crusts. These are hard layers of well-sintered snow often found in the snowpack in mountains as well as in polar regions. Wind-packing affects the local mass balance, the avalanche danger and how the snow cover interacts with the atmosphere. Yet, it is a poorly understood process. Many ideas about what wind-packing actually is have been proposed in the literature but there is almost no quantitative information about the involved physical processes available. A closed-circuit wind tunnel simulating an infinite fetch was specifically designed and built for this purpose. Experiments were performed with natural snow that was collected on a pair of wooden trays. The hardness of the snow and how it changed during experiments was measured with a SnowMicroPen. Meteorological parameters such as wind speed, air temperature, etc. were also measured. In the literature, there is conflicting information about the necessity of drifting ...