‘Brinicle’ Ice Finger of Death - BBC
As sea water freezes to form surface ice, the remaining brine sinks, being much denser and colder than the surrounding water. As it descends, the surrounding water freezes upon contact, creating a ‘brinicle’, a frozen sheath of ice that grows downward towards the sea floor. When it touches the sea floor, it kills anything it touches, encasing them in a tomb of ice.
oh my god this is so fucking cool