Brinicle facts for kids

A brinicle is a fascinating column of ice that forms in very cold ocean water. The name "brinicle" is a mix of two words: "brine," which means very salty water, and "icicle," which you might see hanging from a roof in winter. Think of it like an underwater icicle made of super cold, salty ice!

Brinicles are quite rare and only appear in places where the ocean is extremely cold, like around Antarctica. They are sometimes called "ice fingers of death" because they can be dangerous to slow-moving sea creatures.

What is a Brinicle?

A brinicle is a tube of ice that grows downwards from the bottom of sea ice. It's filled with super cold, salty water. This icy tube forms because of a special process that happens when sea ice freezes.

How Do Brinicles Form?

When seawater freezes to make sea ice, the salt in the water doesn't freeze with it. Instead, the salt gets pushed out, creating tiny pockets of very salty, super cold water called "brine." This brine is much saltier and colder than the surrounding ocean water.

• Step 1: Brine Leaks Out

The super cold, salty brine is heavier than the normal seawater around it. It starts to leak out of the sea ice and sinks downwards, like a very cold, dense stream.

• Step 2: Water Freezes Around It

As this super cold brine sinks, it chills the normal seawater it passes through. This surrounding seawater then freezes around the sinking brine, forming an icy tube or column.

• Step 3: Growing Downwards

The brinicle keeps growing longer and longer as the cold brine continues to sink and freeze the water around it. It can even reach all the way down to the ocean floor!

• Step 4: Spreading Ice

Once the brinicle touches the seabed, the super cold brine spreads out along the bottom, freezing anything it touches.

Why Are Brinicles Dangerous?

Brinicles are sometimes called "ice fingers of death" because they can be harmful to creatures living on the ocean floor. Animals like sea stars and sea urchins move very slowly. If a brinicle reaches them, they often can't move away fast enough. The brinicle then freezes them solid, trapping them in the ice.

Where Can You Find Brinicles?

Brinicles are only found in the coldest parts of the world's oceans, mainly around the Antarctic region. The water needs to be extremely cold for the special freezing process to happen that creates these unique ice formations. Scientists study them to understand more about how ice forms in the ocean and how it affects marine life.

Images for kids

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  Brinicle formation; (1) when water freezes, most impurities are repelled from water crystals, sea ice is very porous, cavities between ice contain brine and saline water, (2) the surrounding water becomes more saline as concentrated brine leaks out. (3) Brine-rich water remains liquid, with the increase in density causes this amount of water to sink. Setting for the creation of a "brinicle". (4) Its outer edges begin accumulating a layer of ice as the surrounding water, cooled by this jet to below its freezing point, ices up as a tubular or finger shape and becomes self-sustaining. (5) The down-flowing cold jet continues to grow longer downward, and reach the seafloor. (6) It will continue to accumulate ice as surrounding water freezes. The brine will travel along the seafloor in a down-slope direction.