Antarctica is a secret world full of unexpected formations, the surface of the ice may look pristine and without great discoveries, but deep beneath the thick icy layer lurk the brinicles, best known as icy fingers of death, which are wild formations that freeze everything that gets in their way.
The icy fingers cling to the back of the Antarctic ice sheet and slowly descend to the ocean floor in twisted, unexpected shapes. They are called brinicles, and while they may resemble the spiky stalactites we find in terrestrial caves, they actually have more in common with hydrothermal vents. But any sea creature that dares to approach the twisted icy fingers must be careful, for any being that does so will be instantly frozen alive.
How Are Brinicles, the Icy Fingers of Death, Formed?
They are called brinicles and are formed by salts in the water separating from the pure ice crystals. In this process, pockets of extra-salty brine can form in channels and fractures in the sea ice layer. Eventually, the brines then seep into the deep sea due to the fractures and eventually run off in the form of inverted sharp needles, because the extra salts make them heavier than the surrounding water, so they appear to drip.
The brinicle-forming water is even colder than the surrounding ocean water, so it absorbs heat, enough to push the already near-frozen seawater over the edge. The result is a sinking current of saltwater that pulls a blanket of frozen seawater around it as it descends into the depths. There are even times when the frozen fingers reach the bottom of the sea, although sufficient saltwater must seep in, and there must be no strong currents to interrupt it.
These marine formations are sublime and show us the power of the dynamics of the abiotic elements of the planet, which despite being lifeless, are capable of sculpting natural art. But as striking as the brinicles are to our eyes, they are not the best place for marine creatures feeding on the ocean floor, as the icy slide of salt needles can continue along the seafloor, freezing anything that dares to get in their way.
In 2011 the BBC crew, as part of the filming of Frozen Planet, managed to capture a brinicle in action as it touched the seabed. As if by magic, the ice spreads across the sediment it touches and freezes sea stars alive. You can watch the video below and be amazed by the momentum of the planet’s phenomena.
Story written in Spanish by Alejandra Martínez in Ecoosfera