Buzz
If you ever set foot on Antarctica's largest ice shelf, the only sound you'd typically hear is the wind's eerie whistle. However, there's another sound, a low rumble that echoes across the frozen expanse, a sound that humans couldn't hear until now.
This audio, shared by the American Geophysical Union, was recorded on Antarctica's Ross Ice Shelf—an ice expanse the size of Texas. In a news release, the researchers describe the eerie tones as resembling a flute or 'the striking of an enormous drum.' This noise is created by winds shifting massive snow dunes, which make the underlying ice sheet vibrate. The frequency is so low it can't be heard by the human ear, so scientists accelerated the 2015 recording by a factor of 1200.
In their newly published study in the journal Geophysical Research Letters, researchers explain how they discovered the Antarctic song by sheer chance. In late 2014, they set up 34 seismic sensors under the thick layer of snow on the Ross Ice Shelf to monitor its movements. It wasn’t long before they realized the ice was constantly humming, a sound unrelated to its gradual shift toward the ocean.
Beyond sounding fascinating, these vibrations also provide crucial insights into the condition of the ice shelf at any moment. The pitch of the glacial tones is influenced by both the positioning of the snow dunes and the surface air temperatures. By analyzing which environmental factors correspond to specific pitches, climate scientists can more effectively monitor the ice's stability—an important task as more ice chunks detach from the continent every year.
