An iceberg is a huge ice mass, sliding from a continent or island into the waters of the ocean or breaking off the coast. This word is translated as "ice mountain". Their existence was first reliably explained by M. Lomonosov. Due to the fact that the ice density is about 10% less than the density of water, the bulk of the iceberg (up to 90%) is hidden below the water surface.
Where icebergs are formed
In the northern hemisphere, their birthplace is Greenland, which constantly accumulates ice and, from time to time, sends excess to the Atlantic Ocean. Under the influence of currents and winds, ice blocks go south, crossing the sea routes that connect North and South America with Europe. The length of their journey in different seasons is different. In spring, they do not reach 50º s. n., and in the fall they can reach 40º s. w. At this latitude are transoceanic sea routes.
An iceberg is a block of ice that can form off the coast of Antarctica. From this place begins their journey to the fortieth latitudes of the Pacific, Atlantic and Indian oceans. These areas are not so in demand among sea carriers, because their main routes go through the Panama and Suez Canals. However, the size of the icebergs and their number here far exceed the performance of the northern hemisphere.
Iceberg-shaped icebergs
Having learned what an iceberg is, you can consider their varieties. Table-shaped ice floes are the result of the process of breaking off large areas of ice shelves. Their structure can be very different: from firn to glacier ice. The color characteristic of the iceberg is inconsistent. Freshly chipped has a white matte hue due to the large fraction of air in the outer layer of compressed snow. Over time, the gas is replaced by drops of water, which is why the iceberg turns a light blue color.
The iceberg-shaped iceberg is a very massive block of ice. One of the largest representatives of this type was 385 × 111 km. Another record holder had an area of about 7 thousand km 2 . The main number of table-shaped icebergs is orders of magnitude less than those indicated. Their length is about 580 m, the height from the water surface is 28 m. On the surface of some rivers and lakes with melt water may form.
Pyramidal icebergs
The pyramidal iceberg is the result of ice landslides. They are distinguished by a peak with a sharp end and a significant height above the surface of the water. The length of the ice blocks of this type is about 130 m, and the height of the surface part is 54 m. Their color differs from the table-like ones in a soft greenish-bluish tint, however, darker icebergs are also recorded. In the thickness of the ice there are significant inclusions of rocks, sand or silt, which got into it when moving around the island or the mainland.
Threat to ships
Icebergs located in the North Atlantic Ocean are considered the most dangerous. Up to 18 thousand new ice hulks are recorded annually in the ocean. You can notice them only from a distance of no more than half a kilometer. This is not enough to turn around or stop the ship in order to prevent a collision. The peculiarity of these waters is that there is often a thick fog that does not dissipate for a long time.
Sailors are familiar with the terrible meaning of the word "iceberg." The most dangerous are the old ice floes, which have substantially melted and hardly protrude above the ocean surface. In 1913, the "International Ice Patrol" was organized. Its employees are in contact with ships and aircraft, collecting information about icebergs and warning about the danger. Predicting the movement of the ice giant is almost impossible. To make them more noticeable, icebergs are marked with bright paint or a beacon operating in automatic mode.