Zastruga

Sastrugi (also: Zastrugi ) or wind Gangeln be called streamlined bumps or grooves in the snow. Sastrugi can be up to 30 cm high and occur mainly in the mountains or in the polar regions. They are hard as a rock and hinder the movement with small snowmobiles or skis.

The word Sastrugi derives from the Russian word заструга ( Zastruga ) and has been adopted in various spellings such as Sastrugus, Sastruga or Zastruga in different languages ​​due to various transcriptions and plurals. In German, only the plural Sastrugi or Sastrugis is mostly used.

Despite a certain visual similarity with cornices Sastrugi arise in contrast to these not by deposition, but by wind-induced ablation of snow. The wind mills the Sastrugi so in places with some harder snow from the previously higher snow out. In contrast to the cornice the steeper side of Sastrugi is the windward, ie upwind side, the flatter the Lee, so downwind side. This is useful for winter sports in the assessment of avalanche danger: In the immediate area of ​​the Sastrugi is indeed usually been no acute danger of avalanches, but they permit subsequent determination of wind strength and direction especially. From this, an experienced winter sports draw conclusions about where the snow was shipped worn and therefore constitutes dangerous snowdrift accumulations.