Procedural desert dunes under a sunset sky with wind-blown sand drifting across the terrain. Drag to orbit, scroll to zoom.
ℹ Details ▾Wind-blown sand is transported mainly through saltation — grains that are lifted briefly by wind shear, then hop and skip along the surface in short ballistic arcs, dislodging further grains on impact. Over time this steady hopping motion causes entire dunes to slowly migrate downwind, with the windward slope eroding and the leeward slip-face accumulating sand at its natural angle of repose. Different wind regimes sculpt different dune forms: crescent-shaped barchans in areas with a single dominant wind direction, long parallel transverse ridges where sand supply is abundant, and pyramidal star dunes where winds blow from multiple directions. Sand movement only begins once wind speed near the surface exceeds a threshold — roughly 4–5 m/s at grain height — below which grains stay put.