Monday, 19 November, 2018

Listen To The Alien Sounds of an Antarctic Ice Shelf

Planet Earth CC0NASA to Launch Laser Equipped Satellite to Track Melting Land Sea Ice
Theresa Hayes | 20 October, 2018, 09:28

Though photographs may present the barren landscapes of Antarctica as eerily calm and peaceful, at least when no storms are raging, the largely lifeless continent and the ice shelves surrounding it produce a medley of bizarrely attractive sounds. The firn had been altered permanently, and the ice shelf song was changed permanently as well.

The snow provides a barrier between the air and the ice, which insulates it from warming temperatures, comparing it to a fur coat. From the data collected, they found the whipping of the winds across snow dunes caused rumbling in the snow blanket. The coating thickness of a few meters acts as an insulating layer, protecting the ice from the heat of the sun.

Researchers have discovered winds blowing across the Ross Ice Shelf, cause it to vibrate, producing a set of seismic tones.

The researchers noticed that the height of seismic hum changes when under the influence of weather conditions of snow dunes "rebuilt" or when the temperature abruptly rises or falls.

Just as musicians change pitch or note by altering how fast and through which holes air flows, strong storms and air temperatures adjust the topography. A result of the seismic changes and wind forces in the area, the ice sheets are 'singing.' Although the scientists call it singing, it is an eerie sound, more like a background score suitable for a horror flick!

"Either you change the velocity of the snow by heating or cooling it, or you change where you blow on the flute, by adding or destroying dunes", Chaput explained. "And that's essentially the two forcing effects we can observe".

Chaput considers seismic monitoring to be a good way to keep an eye on Antarctica's ice shelves, which are considered to be among the most remote locales in the world.

The hum is too low in frequency to be audible to human ears, but the new findings suggest scientists could use seismic stations to continuously monitor the conditions on ice shelves in near real-time. Details like melt ponds or cracks forming that might indicate whether the shelf is liable to break up. In 2002, so suddenly collapsed ice shelf Larsen.