What is the protruding part of an iceberg called? How icebergs form. Secrets of ocean wanderers. Where do icebergs occur?

Last December, photographer Alex Cornell, during his expedition to Antarctica, was lucky enough to photograph an amazing iceberg of an unusual blue color. It turned out that the iceberg turned over and the part of the iceberg that is usually under water became visible. Very beautiful color, I have never seen anything like it before.

Video of how icebergs can turn:

Just beautiful

After these photos, Osya and I talked a lot about icebergs, and here are various interesting facts that you can tell the children:

1. How are icebergs formed?

They break off from large shelf (i.e., floating or bottom-supported) glaciers.

You can launch a small boat and several frozen ice floes in colored water with foam. And conduct a study - what exactly is floating in front of the ship - just a giant ice floe or a real iceberg?

- In plastic molds (for example, from ice cream) you can freeze flat pieces of ice, if you do not pour a lot of water into them.
- Uneven ice will result if you freeze water in dented plastic cups. It’s just better not to wrinkle them too much, otherwise they will crack.
- Separately, you can freeze water in special ice molds, and then these ice pieces will easily stick to each other and you can make different “icebergs.”

We checked whether the iceberg really does not sink, and how much it sinks into the water.

2. Types of icebergs. Icebergs are table-shaped, dome-shaped and pyramidal. An iceberg with a flat surface can easily be mistaken for an island. And it’s comfortable to live on if you’re a penguin.

There are also “dry dock” icebergs - the middle of such an iceberg lies below the surface of the water.

We tried to make icebergs of different shapes, it turned out very funny. The best iceberg is made from ice in a salad bowl.
At the same time, we discussed the bottom of the iceberg. Scientists know of cases where icebergs drifted against the current. And Osya spent a long time guessing how this could be? The whole point is that only a third or fourth of the entire iceberg rises above the surface, while the rest is submerged in water, and there is so much of it that it is “controlled” by active underwater currents.

3. The largest iceberg:
In 2000, the largest known iceberg in history (B-15), measuring 295 km in length and 37 km, broke off the Ross Ice Shelf. This is very difficult to imagine, it seems to me.

4. It's interesting what these ice giants can do travel great distances. For example, icebergs from the Arctic float almost to Bermuda, located 4,000 km from their place of formation. But Antarctic icebergs can be seen in the area of ​​the Brazilian city of Rio de Janeiro. And this is more than 5,000 km from the coast of Antarctica!

5. Floating so far icebergs can be very dangerous for shipping. Everyone knows the tragic fate of the English passenger liner Titanic, which collided with a huge iceberg on April 14, 1912, and as a result sank. Soon after, the International Ice Patrol was created to monitor the movement of icebergs and warn ships of possible danger. And since the beginning of the work of the ice patrol in the North Atlantic, not a single person has died from collisions with icebergs.

It is very interesting that it turns out that there is an iceberg tugboat. The Atlantic Eagle is battling large icebergs in the ocean.

Its only task is to move the iceberg a few degrees from the undesirable course. When a tugboat approaches an iceberg, its crew uses radar to obtain an image of the underwater part of the iceberg. Then the tug goes around it, bending around the ice floe and unwinding hundreds of meters of powerful cable. Having made a loop, both ends are secured to the boat with huge staples. Then, increasing the power of the vessel, they move the iceberg from its place. All this can be very dangerous, because if the iceberg suddenly decides to capsize, it will cause a huge wave or break apart, and this can lead to the sinking of the ship.

6. Iceberg color

Young icebergs are white and consist of ice and air bubbles. These air bubbles form in the glacier from which the iceberg breaks off. When snow is compressed and turns into ice grains, some of the air is also “pressed” into the ice and can occupy up to 15% of the iceberg’s volume. When a glacier moves, cracks form in it. They are filled with water, which, unlike snow, freezes without bubbles. Then blue streaks appear in the iceberg: this is ice free of air.
This is how striped icebergs appear.

They write that in this iceberg, while drifting, sea water and algae got into the cracks and froze:

There are also “black” icebergs: they form when a glacier begins to move and “removes” layers of rock or soil from the surface, which later form black in its thickness. And the black color in icebergs may be a remnant of the volcanic dust that covers their mother glaciers.

Iceberg (German: Eisberg, "ice mountain")- a huge ice floe that has broken off from the edges of a glacier and is drifting in the ocean or sea.
The nature of icebergs was first correctly explained by the Russian scientist Mikhail Lomonosov.

How does an iceberg form?

Icebergs formed from continental ice Antarctica, can rise above the water to a height of 100 meters. The largest iceberg ever measured had 322 km long And 97 km wide.

Icebergs formed from glaciers Greenland and the Arctic islands, much smaller - the largest of them rise up to 70 m above the water surface.

In just one year, about 26,000 icebergs.

For about a year 370 icebergs They pose a threat to navigation, especially in the Atlantic Ocean, as currents carry them into areas where ships move. Therefore, in the open ocean they are constantly monitored by a special service.

In addition, an ice mountain floating in warm waters is usually shrouded in dense fog and it is possible to see the iceberg too late. But today, sailors are warned of danger by radars (radars), which can “see through the fog.

An iceberg is a huge floe of ice floating in the world's oceans.

Where do icebergs come from?

Huge pieces of ice break off from the glaciers that cover the continents and float freely. For example, northern icebergs break off from the Greenland ice sheet, and southern ones from Antarctica, and southern icebergs are much larger in size than northern ones. Not only does the duration of existence and the range of its voyage depend on the properties of an iceberg, it also depends on factors such as the direction and speed of the current in the ocean.

The largest in size and frozen down to -60 C, the icebergs of Antarctica “live” for many years, sometimes even more than a decade. Whereas Greenland icebergs are slightly smaller in size and their deep freezing temperature reaches -30C. They live much shorter, and their melting period is 2-3 years.

Ice is much lighter than water, which explains why even the deepest bodies of water do not freeze completely in winter. If it were the other way around, then, in fact, the ice falling to the bottom would displace the lower layers of water to the surface, and gradually all the water in the reservoir would simply freeze.

But when water freezes, the exact opposite happens. When water transforms into ice, its volume increases by about ten percent, and as a result, the density of ice is much less than that of water. This explains why ice floats on the surface.

At considerable depths of the world's oceans, the water temperature is below zero degrees, but the water there does not freeze. This is interpreted by the pressure that the upper layers of water form.

For the first time, Mikhail Lomonosov answered the question why icebergs do not sink. The density of the iceberg is 920 kg/m?. Additionally, an iceberg or block of ice is made of fresh water and is separated from ice shelves.

Due to the fact that sea water is denser than an iceberg and does not sink completely. And then it is important to know that only a tenth of it floats on the surface of the water - the top, everything else - 90% of this block of ice is hidden under water.

Meeting him is very dangerous for ships on the high seas. If the ship does not notice the moving iceberg in time, then in a collision it can receive very serious damage or even die.

The Arctic and Antarctic are natural “enterprises” for the production of unique environmentally friendly products – icebergs. Antarctic icebergs are much larger than their Arctic counterparts. These are huge masses of ice, sometimes their area reaches several thousand square kilometers! Some icebergs are comparable in size to the Crimean Peninsula.

Iceberg danger

In the desert waters of Antarctica, icebergs pose no particular danger. If they are of interest to anyone else, besides the captains of ships that rarely approach the White Continent, then perhaps glaciologists. Each large Antarctic iceberg receives a name at “birth” and is monitored from airplanes and space satellites until the last day. A much bigger problem is Arctic icebergs. They drift along the shipping lanes of the North Atlantic. Once upon a time, sailors had to rely only on the vigilance of the lookout.

At the beginning of the 20th century, ship sirens began to be used. Their sound reflected from the surface of tall icebergs, warning of danger. And if you came across a low specimen, then you had to rely solely on luck. After the tragic loss of the Titanic as a result of a collision with a huge block of ice in 1914, the International Ice Patrol was created. 13 countries have agreed to patrol the North Atlantic basin. Until the 1940s, patrols in the region were carried out by ships. Since the end of the Second World War, observations have been carried out mainly from the air. Having discovered an iceberg, the patrol determines its exact location, predicts its drift and then transmits radio reports to nearby ships twice a day.

Iceberg formation

Radars installed on ships also make life easier for sailors. But even these modern means cannot provide a complete guarantee of safety. At first glance, the glaciers appear motionless. In fact, they are very plastic and have a consistency similar to thick honey. Under the pressure of its own weight, the ice cap spreads in different directions at an average speed of 10-1000 meters per year. When the edges of a glacier extend out to sea, they become unstable and break off. This is how icebergs form.

In large ice masses, you can see from the air so-called ice rivers, when ice floes create a channel for themselves and “flow” to open ocean water. Having reached the edge of the glacier and breaking off, they form flat and even - table-shaped - icebergs. And glaciologists call ice mountains, distinguished by bizarre shapes of blocks that broke off directly from glaciers. The moment when an iceberg will appear is difficult to predict. In 1986, a piece of glacier unexpectedly broke off in Antarctica, on which the Soviet field expeditionary base “Druzhnaya-1” had recently settled. People were evacuated, and the base's buildings drifted like an iceberg for ten years.

Every year, up to 3.5 thousand cubic kilometers of ice breaks off from Antarctica. The sixth continent supplies more than 90% of the planet's icebergs. Once every 20-25 years, climate fluctuations cause a sharp increase in the number of Antarctic blocks formed. The last time this phenomenon was recorded was in 1986. This means that we can soon expect another “fruitful year”. Ice blocks drifting at the speed of the ocean current quickly melt, taking on the most fantastic shapes on the surface and under water. And the wind, blowing into the holes and crevices of the iceberg, makes it hum mysteriously.

But the shapes of icebergs are more bizarre, and therefore the repertoire is much richer. Getting close to icebergs is dangerous. Due to melting, the center of gravity between its surface and underwater parts constantly shifts, and the block can turn over in a matter of seconds. At best, the ship will be hit by a rising wave.

Icebergs capsize more than once during their journey.. But this does not stop thrill-seekers. Iceberg diving has become one of the extreme sports. It’s not just extreme sports enthusiasts who risk approaching these unstable mountains of ice.

The iceberg area is an excellent place for fishing and hunting. Once in warm latitudes, the iceberg begins to melt, and krill - planktonic sea crustaceans - accumulate around it. They are attracted to cool water. Next come krill-eating fish, followed by birds, seals and bears. Hunters and fishermen arrive last.

Ecologically clean water from icebergs in the coastal countries of the North Atlantic is used in the food industry, in particular for the production of exclusive alcoholic beverages. The Canadians were especially successful in this, who began “fishing” for icebergs in 1971, towing the first block of ice to the port. Towing icebergs to dry areas could solve the problem of drinking water, the lack of which affects 2 billion people on Earth. The clean, cool water of icebergs could save dying reefs.

In Russia, the city authorities of Vladivostok are seriously thinking about obtaining fresh water from ice blocks. Nowadays, tourist cruises are increasingly being organized to areas where icebergs drift, but sailors prefer to remain at a respectful distance. Fortunately, in clear weather, the “vagrants of the seas” shining in the sun are visible from afar.

After the famous blockbuster Titanic, no one needs to explain what an iceberg is. Of course, a huge ice mountain floating in the open sea-ocean.

But in fact, much about this natural phenomenon remains unknown to the general public. For example, you know...

Why does an iceberg float?

More precisely, why does ice float on water? If you melt sugar and throw a piece of refined sugar into it, it will drown. Solid wax sinks in its own melt. Thousands of other substances behave in exactly the same way. But water behaves differently.

Unlike many other liquids, its molecules do not float in a glass or river on their own, but each is connected to four or five others. And when it freezes, it turns into crystals, where the “packing” of molecules is no longer so dense. That is, ice has a lower density than water, which is why it floats. It wouldn’t surprise you if a piece of wood or sunflower oil floated on the water, would it? They also have a lower density than water. But when ice freezes, it also traps air bubbles. How can he not swim!

“An iceberg grows out of the fog like an icy mountain...”

An iceberg can emerge from the fog, from the darkness, from around a corner. But where do such mountains of ice come from? Even if the sea freezes, flat ice floes will appear, albeit thick, but not such shapeless hulks as icebergs.

In fact, the sea has nothing to do with it. Because icebergs are born... on land, in the polar North and Antarctica. The eternal snow that covers the northern mountains, for example, Greenland, is compressed and turned into an ice sheet over a kilometer thick.

Under their own weight, the glaciers slowly slide down and their edges hang over the ocean. Giant fragments break off from them with a roar. Sometimes, even on the slope, a crack runs across the ice tongue and its multi-ton “tip” slides into the water. And then the fate of the iceberg is decided by winds and currents.

As it moves through shallow water, its sharp underwater edges can plow deep into the seabed. Once in open waters, it drifts. The underwater part is gradually overgrown with plant organisms, and small crustaceans are attached to it. Birds travel on top of icebergs.


The most impressive thing about an iceberg is its enormity. Despite the fact that no one has ever seen the entire iceberg from top to bottom: after all, over 90% of its mass is hidden under water. A 75-meter surface height and a mass of 200,000 tons are not uncommon in the world of icebergs. The largest recorded in the North Atlantic had an apparent height of 55 stories. In 1956, an iceberg wandered in the south Pacific Ocean, which could not even be called a mountain - it was a real island the size of Ireland and larger than Belgium. In 2000, an iceberg weighing over 3,000,000,000,000 (three trillion!) tons floated near Antarctica.

"And this iceberg will melt..."

The iceberg is not doomed to melt. It can be frozen for a long time in the thick ice covering the sea. Then thaw, swim and freeze again. Inside the ice mountain, the temperature stays at –15…–20°C. However, the outer layers gradually melt, especially if the iceberg ends up in warm latitudes.

When melting, huge caves are formed inside the iceberg, blocks break off from the ice monolith with noise. By the way, when melting, an iceberg makes short hissing sounds. These frozen compressed air bubbles are released and burst, jumping out to the surface of the ocean. Eventually, all the millions of tons of frozen fresh water liquefy and dilute the ocean. Icebergs live on average for two years.

Since the 1950s, experts have recorded a general decrease in Antarctic ice cover. Its fragments go into the ocean like icebergs and, of course, do not return. Of course, new ice grows instead, but the overall stability of the ice sheet decreases. Scientists fear that huge glaciers will creep toward the water, and no one knows what this will lead to.

Keep your eyes open!

It is clear that even not very large icebergs are dangerous for shipping. Nowadays, large ships are equipped with radars that warn the crew of possible unpleasant surprises.


Since the beginning of the 20th century, an international system for detecting and tracking icebergs has been established. Now these tasks are performed by spacecraft around the clock, regardless of earthly weather. Each “newborn” iceberg receives its own code name (such as D-16), and the fate of the ice mountain is monitored. It broke up - they “monitor” every large fragment. It seems that the fate of the one and a half thousand who died on the Titanic taught humanity something.