Sculpted Snow (I)

In case you're wondering how these form: a very thin layer of snow at the top melts and re-freezes to ice; wind then erodes away the unstable snow until only the thin sheet of ice remains.

if additional snow falls on top of the ice sheet before it is eroded away, the new layer will not bond to the ice or the snow layer below and remain unstable. Such intermediary layers of ice therefore greatly increase the risk of avalanches.