Icicle

An icicle is a spike of ice.

It forms when water drips and freezes. Sunlight can melt snow or ice. Then the water drips and turns to ice. This makes the icicle grow longer.

Icicles can hang from many things. They can hang from twigs or wires. They also grow on cliffs. Sometimes they look like frozen waterfalls. Large icicles can be very heavy. They might fall and cause damage. Please stay safe near them.

An icicle is a spike of ice. It forms when water drips from an object and freezes.

Sunlight can melt snow or ice. This melting water drips down. The water then refreezes in the cold air. This way, the icicle grows longer and wider over time. Sometimes water seeps out of cliffs. This can make frozen waterfalls. In caves, these ice spikes are called ice stalactites.

Icicles can also form in the ocean. They grow from salty water called brine. These are known as brinicles. They can even kill sea urchins and starfish.

Icicles can be dangerous. They can fall and hurt people. They can also hit cars. If many icicles grow on a wire or pole, they become very heavy. This weight can break the object. On roofs, icicles can cause water damage. In 2010, many people were hurt by icicles in Russia. Heavy snow also made some roofs fall down.

An icicle is a spike of ice. It forms when water falls from an object and freezes.

This can happen on sunny days when it is still very cold. Sunlight might melt snow or ice on a roof. This melting water drips down and refreezes in the cold air. Over time, the water runoff makes the icicle grow. Icicles can also form during ice storms. In those storms, rain falls through freezing air. This creates many small icicles on leaves, wires, or twigs.

There is a special way that icicles grow. They grow like a tube around a falling drop of water. The wall of this ice tube is very thin. Because of this, the inside of a growing icicle stays liquid. The growth depends on many things like wind speed. It also depends on the air temperature and water flux. Water flux is just the amount of water flowing in. The length of an icicle can change quickly. In ideal conditions, it can grow more than 1 centimeter per minute.

Icicles can also form in places you might not expect. If they grow in a cave, they have a new name. People call those ice stalactites. Icicles can even form in the salty water of the ocean. This salty water is called brine. When brine sinks from sea ice, it forms brinicles. These are often called ice fingers of death. BBC film crews saw these near Mount Erebus in Antarctica. They filmed them in a show called Frozen Planet in 2011.

While they look pretty, icicles can be quite dangerous. They can fall and cause injury to people below. They can also hit and damage cars on the road. If too many icicles grow on a pole, they get very heavy. This weight can break the pole or a wire. On a house, they can cause ice dams. These dams let water leak under the shingles. In 1776, a story was told about a boy killed by a falling icicle.

Large icicles can cause big problems in cities. In 2010, Saint Petersburg, Russia, had a very bad time. Icicles hurt five people and injured 150 others there. Heavy snow also caused roofs to collapse in that city. This damage even reached the National Library of Russia. A 2022 study looked at how icicles affect the body. It showed they can penetrate most parts of a human body. They can even reach vital organs if they are deep enough.

An icicle is a spike of ice formed when water falls from an object and freezes. These frozen structures are common in cold environments. They often appear when melting snow or ice drips from a surface. This process can happen even during bright, sunny weather. If the air temperature remains below freezing, the water refreezes as it drips. Icicles can grow into many different shapes. Their form depends on the surface they hang from. A smooth surface might create a straight icicle. An irregular surface might create a more complex shape.

The growth of an icicle is a specific physical process. It grows by forming an ice tube around a pendant drop of water. The wall of this ice tube is very thin. Because the wall is so thin, the interior of a growing icicle remains liquid water. The rate at which an icicle grows in length and width is a complicated function. It depends on air temperature, wind speed, and water flux. Water flux is the amount of water flowing into the icicle. In ideal conditions, the length can increase by more than 1 centimeter per minute.

There are several distinct ways that icicles form in nature. One way occurs during ice storms. In these storms, rain falls through air that is slightly below freezing. This rain accumulates as many small icicles on twigs, leaves, or wires. Another way is through water seeping from vertical surfaces. This often happens at road cuts or on cliffs. If the conditions are right, these can form frozen waterfalls. These large structures are often used by ice climbers.

Icicles can also be found in unusual environments. When they form inside caves, they are known as ice stalactites. They can even form in the ocean within salty water called brine. As brine sinks from sea ice, it can create structures called brinicles. These are sometimes called "ice fingers of death." BBC film crews observed these near Mount Erebus in Antarctica. They filmed this phenomenon for the show Frozen Planet in 2011. These brinicles are powerful enough to kill sea urchins and starfish.

While they are beautiful, icicles pose significant personal and structural dangers. Falling icicles can cause injury to people or damage objects below. They can also be very heavy. If many icicles form on a wire, beam, or pole, the weight is immense. This weight can damage the structural integrity of the object. It can even cause the object to break. On roofs, icicles are often linked to ice dams. These dams allow water to penetrate below the shingles of a building.

History and research have documented the dangers of these ice spikes. A story from 1776 recounts an English youth killed by a falling icicle. Modern science has also studied their impact on the human body. A study from 2022 showed that icicles can penetrate most of the human body. With enough depth, they can reach vital organs. The only major exception noted was the chest region. Large icicles on cliffs near highways can also damage moving motor vehicles.

Large-scale events show how dangerous icicles can be in populated areas. In 2010, Saint Petersburg, Russia, experienced a major incident. Five people were killed and 150 people were injured by icicles there. This happened after heavy snow caused apartment block roofs to collapse. The ice and snow also caused water damage to private homes. This damage even affected the National Library of Russia. These events show how ice can impact entire cities and important buildings.