Bird Woman avalanche

Examining a glide crack in the Bird Woman avalanche path along the Going-to-the-Sun Road. The process of snow sliding downhill along the snow-ground interface is called glide. When glide rates vary spatially over a given slope a glide crack forms upslope of the faster glide area. These glide cracks can fail as avalanches over time.
Photo courtesy of Erich Peitzch, USGS.