Why Do Sand Dune Avalanches Boom, Burp and Sing?

Avalanching dunes can create their own music, when toppling sand erupts first with staccato burps and then with monotone "singing" booms. These tunes have long intrigued scientists, and now a team of physicists has deciphered why they occur.

via LiveScience.com http://ift.tt/1KQudVM