Hunting monsters…with sound

Milton Garces
Milton Garces

UH Mānoa’s Milton Garces has contributed a new essay to the Sounding Out blog’s “Hearing the Unheard” series.  The story highlights Garces’ research work in infrasound, low-frequency sounds in the atmosphere that are inaudible to the human ear, but can carry for thousands of kilometers.  Infrasound has a variety of important and practical applications including its use in detecting secret missile tests and enforcing the provisions of the Comprehensive Nuclear Test Ban treaty.

In particular, Garces’ Sounding Out story shines a light on his work with the infrasound signature of volcanoes.

“Like a large door slamming, the concussion of a volcanic explosion can be startling and terrifying. It immediately compels us to pay attention, and it’s not something one gets used to,”  Garces writes.

The roaring is also disconcerting, especially if one thinks of a volcano as an erratic furnace with homicidal tendencies. But occasionally, amidst the chaos and cacophony, repeatable sound patterns emerge, suggestive of a modicum of order within the complex volcanic system. These reproducible, recognizable patterns permit the identification of early warning signals, and keep us listening.”

Read Garces’ full Sounding Out essay here, or learn more about Garces’ research here.

Infrasound data
Infrasound data, Kelut Eruption, Java, Indonesia. Courtesy UH Infrasound Laboratory.