Sastruga is a rather obscure word but one with a clear definition in meteorology: a wind-created ridge on a snow surface. The process is not greatly different from that which forms sand dunes. Snow-dune or ripple formation isn’t just a larger-scale effect of sand over many square miles; it can happen on scales of feet inches under the right conditions. Here, miniature transverse dunes, with minor barchanoid tendencies, remained atop the snow on the morning after a blizzard. Howling NW winds of 40-60 mph blasted along this curvy hillside, and generally across the direction of these little ridges in the snow. Without something for scale, such as the small sticks poking from the snow at upper left, this easily could pass for an aerial shot of a desert of white sand from a plane, or perhaps a glacial surface rippled by structural stresses. Bigger sastrugi assume the form and sometimes even size scale of small sand dunes, making cross-country skiing and snowshoe walking difficult.
Norman, OK (25 Dec 9) Looking NNE
35.2077, -97.3759