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

[Judi Lynn]

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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

[Think. Again.]

1. Thank you, I had assumed from the title...

...that this would be an article on the rivulets of warmer, melted water that have begun reaching under the ice bed and threatening to dislodge (and then melt) the vast areas of frozen ice that keeps our sea-levels from rising incredibly high.

What Lies Beneath Melting Glaciers and Thawing Permafrost?

"The Arctic is warming four times faster than the rest of the planet, and this means that glaciers, which sit on land, and sea ice, which floats on the ocean surface, are melting rapidly. Two-thirds of Arctic Sea ice has disappeared since 1958 when it was first measured. Between 2000 and 2019, the world’s glaciers lost 267 billon tons of ice each year. Himalayan glaciers are on a trajectory to lose one-third of their ice by 2100, and Alpine glaciers are projected to lose half of theirs.

“I can tell you from our research that the bedrock underneath the ice will become exposed at a much higher speed than we think,” said Joerg Schaefer, a climate geochemist at the Columbia Climate School’s Lamont-Doherty Earth Observatory who is researching the Greenland ice sheet. “All of the predictions are way too conservative in terms of change—the change will be much faster. That’s true globally. But Greenland might be one of the areas where these predictions of ice change are way, way, way too conservative because of a variety of climate factors.”
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Source: https://news.climate.columbia.edu/2022/09/13/what-lies-beneath-melting-glaciers-and-thawing-permafrost/

Why Are Glaciers Melting from the Bottom? It’s Complicated

"Scientists already generally agree that glacier retreat in Antarctica is largely being driven by warm water seeping underneath the ice—the process has been demonstrated by multiple studies in the last few years. As the ice melts, the point where it attaches to the bedrock at the bottom of the ocean (commonly known as the “grounding line”) recedes inland, which can cause the glaciers to become less stable and lose more ice over time."
-snip-
Source: https://www.scientificamerican.com/article/why-are-glaciers-melting-from-the-bottom-its-complicated/

[erronis]

2. What a fascinating story with a very gripping video. Life, and death.

Thank you so much Judi for bringing these articles to our attention. Science, even the grim truth, brings reality to our lives. After all, politics and human foibles will be subsumed by science, in the end.