The tallest stationary dunes on Earth can also sing! Over 1,600 feet tall, the Badain Jaran Desert Dunes in China are roughly the same height as the world's tallest buildings and hold a mysterious property known as singing sands, whistling sands, or booming dunes.
This rare occasion emits a sharp, loud noise that can be maintained for more than a minute. It is believed that it is caused by an electrostatic charge that is generated as wind pulls the top layers of sand down a dune slope, producing a low pitched rumble that can reach over 105 decibels.
Booming dunes are silent in the wintertime when moisture from precipitation is retained in the dune. The burping property depends on sand grain characteristics and can be generated all year around. In the summer time when the larger dunes produce their music, the smaller dunes in the dune field remain silent. This indicates that structural properties of the dune are critical for the generation of the singing sand. Also, booming can only be generated at slopes at the angle of repose (30 degrees) on the leeward face of dune; the same sand on the shallower windward side cannot generate the music.
Picture Credit : Google