Sastrugi dunes, and the resulting drifting snow shapes are also popularly referred to as "barchans". Inuit of Canada call them "kalutoqaniq". When winds slacken, the drifted formations consolidate via sublimation and recrystallization. Subsequent winds erode kalutoqaniq into the sculptured forms of sastrugi. Inuit call large sculpturings "kaioqlaq" and small ripples "tumarinyiq". Further erosion may turn "kaioqlaq" back into drifting "kalutoqaniq". An intermediate stage of erosion is "mapsuk", an overhanging shape. On the windward side of a ridge, the base erodes faster than the top, producing a shape like an anvil tip pointing upwind. Sastrugi are more likely to form on first-year
Surface wave detection by animals sensitive range of 75–100 Hz. Fish are also sensitive to waves generated within 7–30 cm of the fish’s location, though they can occur at any point within that radius. Because the water surface acts as a low pass filter, this radius is different for different wave frequencies: 70 Hz waves with 100μm peak-to-peak distance are subthreshold at 37 cm, and 140 Hz waves are subthreshold at 19 cm. Fish are able to tell apart concurrent waves of different frequencies when the frequencies are different by at least 15%, though at certain frequencies this difference can be as low as 8%.