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
Periodic Bedrock Ridges water working on the surface." Periodic Bedrock Ridges Periodic Bedrock Ridges (PBRs) are features of the surface geomorphology of Mars and formerly unknown on Earth, first described in a paper in the Journal of Geological Research - Planets, in March 2012, by Professor David R. Montgomery, Joshua L. Bandfield, and Scott K. Becker of the University of Washington. Evidence for sediment transport and erosion by wind is widespread over the surface of Mars today and was likely a major geomorphic process for much of its geological past. Although Martian surface features resembling aeolian dunes and ripples have been recognized since