Frost
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Frost is a layer of ice on a solid surface, which forms from water vapor that deposits onto a freezing surface. Frost forms when the air contains more water vapor than it can normally hold at a specif
A patch of grass showing three zones. crystalline frost in the below-freezing shade (blue, lower right) frost in the warming but still below freezing strip most recently exposed to sunlight (white, center) frost-free region: here, the previous frost has melted from a more prolonged exposure to sunlight (green, upper left.)
Frost in the highest town in Venezuela, Apartaderos: Because of its location in an alpine tundra ecosystem called páramo, a daily freeze-and-thaw cycle, sometimes described as "summer every day and winter every night", exists.
A spider web covered in air hoar frost
Air Hoar with ruler for scale
Avalanche
Videos
An avalanche is a rapid flow of snow down a slope, such as a hill or mountain. Avalanches can be triggered spontaneously, by factors such as increased precipitation or snowpack weakening, or by extern
Frost
…crystals, so typically are visibly stepped and have faceted hollows. When surface hoar covers sloping snowbanks, the layer of frost crystals may create an avalanche risk; when heavy layers of new snow cover the frosty surface, furry crystals standing out from the old snow hold off the falling flakes, forming a layer…
A powder snow avalanche in the Himalayas near Mount Everest
Loose snow avalanches (far left) and slab avalanches (near center) near Mount Shuksan in the North Cascades mountains. Fracture propagation is relatively limited.
15 cm deep, soft slab avalanche triggered by a snowboarder near Heliotrope Ridge, Mount Baker in March 2010. Multiple crown fracture lines are visible in the top-middle of the image. Note the granular characteristic of the debris in the foreground that results from the slab breaking up during descent.
Avalanche on Simplon Pass (2019)