When the wind blows, Antarctic’s ice shelf ‘sings’
Winds blowing across snow dunes on Antarctica’s Ross Ice Shelf cause the massive ice slab’s surface to vibrate, producing a near-constant set of seismic “tones” which could be used to monitor changes in the ice from afar, according to a study. The Ross Ice Shelf is Antarctica’s largest ice shelf, a Texassized plate of glacial ice fed from the icy continent’s interior that floats atop the Southern Ocean, said researchers at Colorado State University in the US.
The ice shelf buttresses adjacent ice sheets on Antarctica’s mainland, impeding ice flow from land into water, like a cork in a bottle, according to the study published in the journal Geophysical Research Letters. When the researchers started analysing seismic data on the Ross Ice Shelf, they noticed something odd: Its fur coat was almost constantly vibrating.
“It’s kind of like you are blowing a flute, constantly, on the ice shelf,” said Julien Chaput, a geophysicist at Colorado State University. To better understand the physical properties of the Ross Ice Shelf, researchers buried 34 extremely sensitive seismic sensors under its snowy surface. The sensors allowed the researchers to monitor the ice shelf’s vibrations and study its structure and movements for over two years, from late 2014 to early 2017.
Researchers discovered winds whipping across the massive snow dunes caused the ice sheet’s snow covering to rumble, like the pounding of a colossal drum.