The Kelso Dunes Sing

The Kelso Dunes rise six hundred fifty feet above the Mojave Desert floor, among the tallest dunes in the Mojave and among the tallest in the United States. They are visible from miles away, a long pale mound against the creosote flats, shaped by winds from the southwest that carry sand from the Mojave River basin and deposit it here in a formation that has been accumulating for tens of thousands of years.

What most visitors do not know until it happens is that these dunes can make a sound.

Under the right conditions: specific grain-size uniformity, low enough humidity, the right slope angle on the lee face of a dune, an avalanche of sand sets off a resonance that physicists studying granular flow have documented in detail. The dry, well-sorted quartz grains vibrate in synchrony as they cascade, and the vibration couples with the dune itself, which acts as an amplifier. The result is a deep, low booming sound that some accounts compare to a cello note, some to a distant aircraft engine. The sound can carry for miles. It lasts for seconds, sometimes longer, and then the avalanche stops and the desert is quiet again.

The conditions that produce it are specific enough that most visitors will hear nothing unusual. Wet winters can disrupt the grain moisture balance for months. But on a dry day in late spring or early fall, if you climb the steep avalanche face and send a wave of sand cascading, the dunes may answer you.

Singing dunes exist in a handful of places worldwide: the Sahara, the Gobi, a few sites in South America. The Kelso Dunes are among the most reliably musical in the American West. The desert is rarely still. Sometimes it is actively audible.