Sastrugi sea ice than on multiyear ice. First-year ice is smoother than multiyear ice, which allows the wind to pass uniformly over the surface without topographic obstructions. Except during the melt season, snow is dry and light in climates cold enough for sea ice, allowing the snow to be easily blown and create sastrugi parallel to the wind direction. The locations of sastrugi are fixed by March in the northern hemisphere and may be linked to the formation of melt ponds. Melt ponds are more likely to form in the depressions between zastrugi on first-year ice. Sastrugi Sastrugi, or zastrugi, are
Surface states be satisfied for each formula_24 separately and for each formula_24 a single, but generally different energy level for the surface state is obtained. A surface state is described by the energy formula_26 and its wave vector formula_24 parallel to the surface, while a bulk state is characterized by both formula_28 and formula_29 wave numbers. In the two-dimensional Brillouin zone of the surface, for each value of formula_28 therefore a rod of formula_29 is extending into the three-dimensional Brillouin zone of the Bulk. Bulk energy bands that are being cut by these rods allow states that penetrate deep into the crystal.