Pack ice: features, formation, distribution

Pack ice is a unique naturalphenomenon. It is observed only in the northernmost latitudes of the planet, in the Arctic region. Once this term was applied absolutely to all drifting ice, but after conducting multiple studies, the packs were separated into a separate group. They have a number of properties that distinguish them from other types of ice. The definition of "perennial ice" is synonymous, so it occurs about the same frequency.

Features of pack ice

Researchers in the Arctic, sailors and travelers,who at least once had to visit the northern latitudes, are well aware of what pack ice is. This phenomenon brings a lot of trouble to the conquerors of the north.

These ice drift in the ocean, their mass is enormous, yesand the density is very high. Accidental collision can cause considerable damage even to the most modern vessel. Pack ice differs from ordinary ice with its properties. According to experts, the pack is formed from sea water, its thickness exceeds 3 meters. It is denser than ordinary ice because of the extremely low salt content.

The process of formation of pack ice

Ice is formed in the northern latitudes in conditionslow temperatures. When the sea water freezes, a process of desalination takes place, thawed water always has a salinity level lower than the original one. This is a distinctive feature of the packs, which pass the process of freezing and thawing several times.

Sea water is frozen, icebergs are formed andlarge ice floes. Subsequently, smaller ice floes disconnect from large ice massifs, many of which later turn into packs. They are not characterized by any common signs in forms. There are a variety of packs: from flat ice to huge blocks, towering above the sea surface.

The researchers found that, beforestart off in the sailing, pack ice takes at least 2 annual cycles of freezing and freezing. This is the cause of its high density and low salinity. The fact is that when thawing and re-freezing the water, the salt is thrown into the ocean. Seafarers know that old pack ice is suitable even for fresh water, on which you can prepare food.

The range of "habitat"

Packed ice in the Arcticthe ocean. In the South of the planet, in the Antarctic region, there are none, so they do not occur in any other ocean. The high density and unpredictability of the drift trajectory can hamper the movement of even the most powerful nuclear icebreakers. It is for this reason that the sought-after path between the Bering Strait and Murmansk passes not through high latitudes (the North Pole), but along the northern coast of the continent. The high-latitude course is shorter by a third, but the movement of pack ice makes it too difficult. Therefore, it is not used in the transport message on a permanent basis. Of course, there are many ships that have passed this difficult course. Professionals know that it is possible to pass it, especially under the guidance of the icebreaker. But on the regular flights so far it is not conducted.