What Are The Sinister "Fingers Of Death" Beneath Antarctic Ice?

[Judi Lynn]

clock-icon
PUBLISHED
17 hours ago

Good luck to anything that gets in its way.


While most of us wouldn’t fancy being in the -2°C (28.4°F) water underneath Antarctica’s winter ice, for the sea-dwelling critters that usually live there, it’s positively balmy compared to the surface above. In fact, life thrives there – that is, until a so-called “finger of death” appears.

In the clip below from the BBC series Earth’s Great Seasons, film crews managed to capture the formation of one such finger, as it eerily crept toward the seabed and, once touching, proceeded to freeze everything within its path.

While such footage might give off the same vibe as a movie featuring the invasion of sinister long-fingered aliens, luckily, no extraterrestrial activity is involved – it’s a brinicle, a tube of ice that grows down in just a matter of hours, containing brine within it.

How do brinicles form?
When sea ice forms, the salts in seawater don’t become part of the structure; instead, they form pockets of cold brine within the ice, not freezing because of the high salt content. If given the chance to escape into the water below, this brine ends up sinking – the salt content makes it much denser than the water it’s going into.

More:
https://www.iflscience.com/what-are-the-sinister-fingers-of-death-beneath-antarctic-ice-75961