Long-wavelength transverse bedform in Antarctica.
Transverse, long-wavelength surface ripples characterized by m-scale heights and km-scale wavelengths. Areas between the dune forms on the ice sheet are called wind glaze regions, which have near-zero accumulation.
Antarctic snow megadunes represent 2–4 m amplitude waves of 2–5 km wavelength (Frezzotti et al. 2002).
Snow megadunes represent antidunal formation in a polar environment dominated by blowing snow under very consistent wind conditions. These features form as a result of standing wave patterns formed in an inversion air layer when the layer of flowing air is perturbed by a hill or other feature on the ice sheet. They form only in regions with highly persistent katabatic winds. The local accumulation is redistributed to the dune areas, with regions of essentially zero snowfall between them (Frezzotti et al. 2002, Scambos et al. 2012).
Upper Byrd Glacier catchment in...
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