Brinecicles

The underside of the ice shows some curious stalactite-like features, also called brinecicles. As the ice on top of the sea grows, a dense and cold (very salty) brine forms that eventually sinks down into the ocean. When the ice is thick enough these brines collect in channels before they are expelled into seawater. These super-cold brines enter the seawater along these channels and actually freeze some of the seawater, forming "brinecicles".

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