The winds cause the massive ice slab's surface to vibrate, producing a near-constant set of seismic tones scientists could potentially use to monitor changes in the ice shelf from afar, according to new research led by Colorado State University. Scientists initially installed 34 seismic sensors under the surface of the Ross Ice Shelf to track the ice's movement and structure over the course of 2 years.
With this newfound ability, researchers could use seismic stations to continuously monitor the conditions on ice shelves nearly in real time, allowing us to see how the ice shelf's snow jacket is responding to changing climate conditions.
Global warming has caused over three trillion tons of ice to melt from Antarctica in the past quarter-century and tripled ice loss there in the past decade.
Everyone's getting in on the eerie Halloween mood these days, even the ice in Antarctica.
The resulting data showed something unusual: the "fur coat" snow layer that protects the ice from heat was constantly "singing", or vibrating.
When they looked at the data, they realized the top layer of the shelf (called the firn) was nearly constantly vibrating, thanks to the winds travelling atop the snow dunes.
Ice shelves are covered in a thin blanket of snow, typically several meters deep, that insulates the ice below from warming and melting like a fur coat. As storms altered dune patterns and the texture of the ice shelf's snowy surface, the pitch of the seismic tune shifted. Scientists say the sounds could alert them to the shelf's condition under climate change, like a kind of warning sound for the planet.
While normally inaudible to the human ear, the researchers have made these ultra-low frequencies detectable to our limited hearing range.
"Basically, what we have on our hands is a tool to monitor the environment... and its impact on the ice shelf", he added.
But if we deployed seismic sensors on more ice shelfs, you could observe subtle environmental changes, in minutes.
The findings were reported in the journal Geophysical Research Letters.