Snow snow has many aspects climate high albedo

Snow 雪 snow has many aspects • climate: – high albedo, latent heat flux, surface temperature – sea ice: snow cover, ice growth, freeboard – formation of glaciers and ice sheets • human affairs: – economical: traffic, transportation, snow removal – natural hazard: avalanches – touristic: skiing Bernhard Russi and Therese Nadig won downhill ski gold medals on 恵庭岳 at winter olympics in 札幌 in 1972　

growth of snow crystals

Snow cover • Large seasonal change of snow covered land surface (and sea ice) • Large year to year variation • Increase of surface albedo: large influence on weather and climate • Impact on human activities: transportation, mobility, dangers, recreation

northern hemisphere snow cover

trend in snow depth

duration of snow season in Switzerland

Snow mechanics

Snow physics Dr. Martin Schneebeli SLF, Davos, Switzerland

snow metamorphosis 雪の変態

Water in snow • complex drainage, percolation, melt and freezing patterns in snow

surface frost

weak layer with hoar frost: forms in temperature gradient in the snow layer

• weak layers: slab avalanches

snow profile

Slab avalanche

Avalanches 雪崩 powder avalanche slab avalanche

snowdrift 雪の漂流

snow deposit by wind drift snowdrift

snow drift simulation

simulated snow deposit: wind from upper right

Snow fence • many snow fences along roads in 北海道