English term for Pukak. Hoar means old frost, so it is old frost in snow.
Fragile crystal formed within the snow cover when strong temperature gradients induce existing snow crystals or grains to recrystallize by passing through the vapor phase.
large (one to several millimeters in diameter), cohesionless, coarse, faceted snow crystals which result from the presence of strong temperature gradients within the snowpack
Also called TG (temperature Gradient) Snow, the bane of backcountry skiers. A weak layer of poorly bonded snow which may or may not be visible upon digging a snow pit. Depth Hoar is commonly formed/found in early winter, and is more prevalent in the continental Rockies than in the pacific coast ranges. Depth Hoar greatly increases avalanche risk, making some regions unsafe until spring, and melt/freeze metamorphosis takes place
more info Large-grained, faceted, cup-shaped crystals near the ground. Depth hoar forms because of large temperature gradients within the snowpack.
end product of temperature gradient metamorphism. Large cohesionless grains with facets and stepped surface. Also called facets.
a layer of snow made up of round or cup-shaped crystals that act like ball bearings, allowing the layer of snow on top to slide of easily; also known as sugar snow
Large-grained, faceted, cup-shaped crystals near the ground. Depth hoar is caused by large temperature gradients within the snowpack, usually in the early winter, by large temperature differences between the warm ground and the cold snow surface.
Ice crystals (usually cup-shaped, faceted crystals) of low strength formed by sublimation within dry snow beneath the snow surface; a type of hoarfrost. Associated with very fast crystal growth under large temperature gradients. This is one way in which firn formation may begin. Depth hoar is similar in physical origin to crevasse hoar Hoarfrost composed of crystals that have built up a three-dimensional complex of faceted, rather than rounded, crystals.