What types of seas are internal, external, etc. Interesting facts about the sea

Divisions of marine bodies of water (parts of the World Ocean) into types based on natural characteristics. There is no generally accepted K. m. based on taking into account the entire complex of their features. Various K. m. are based on individual characteristics (physiographic, morphological, hydrological, tect.). Krummel (1907) and Shokalsky divided the seas according to their position into Mediterranean seas And marginal seas. Muromtsev (1951) highlights inland, marginal seas And interisland, based on their hydrogeological regime. Bass shape. Strakhov (1954) distinguishes the seas flat and hollow, and according to the position and type of sedimentogenesis - inland And outlying humid and arid zones. By text. signs are usually identified platform seas(Also shelf, epeirogenic) And geosynclinal. Panov (1963) proposes dividing the seas according to text. structure into marginal-continental, shelf, depression and geosynclinal.

Geological Dictionary: in 2 volumes. - M.: Nedra. Edited by K. N. Paffengoltz et al.. 1978 .

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Many of us have been to the sea and know how wonderful it is to relax on the beach in the summer, swimming in the water from time to time. Sea water relaxes, pacifies and heals our body. And today we will talk about this beautiful masterpiece of nature from a scientific point of view. So let's find out what the sea is.

A sea is a specific part of the ocean from which it is separated by land. Simply put, the sea is a lot of salt water. The sea comes in different colors, and the color depends on what part of the world it is in.

Classification of seas

There are the following classifications of seas:

  • By water temperature;
  • Along the ruggedness of the coastline;
  • According to the degree of isolation from the ocean;
  • Across the oceans;
  • According to the degree of water salinity.

Classification by ocean

There are sixty-three seas on our planet. Of these, eleven belong to the Indian Ocean (Timor Sea, Arabian Sea), eleven to the Arctic Ocean (Barents Sea, Greenland Sea), sixteen to the Atlantic Sea (Marmara Sea, Irish Sea, Caribbean Sea) and twenty-five to the Pacific (Sea of ​​Japan, Aki Sea, Coral Sea, Sea of ​​Okhotsk). You can read more about all the seas in our article.

Classification by water temperature

There is also a division of seas according to the temperature of their waters.

So, there are seas:

  • The seas are polar;
  • Seas of the temperate zone;
  • Tropical seas.

As for the polar seas, their temperature is generally nineteen degrees below zero.

In tropical seas, the water temperature averages seventeen degrees above zero.

And in tropical seas the temperature can be twenty-four to twenty-seven degrees above zero.

The temperature of the seas depends on the inflow and outflow of heat. The sea receives heat from solar radiation, and uses this heat to exchange with the atmosphere and evaporate water.

Classification by degree of isolation from the ocean

There are seas:

  • Intercontinental;
  • Internal;
  • Interisland;
  • Outskirts.

Intercontinental seas. Land almost completely surrounds them, and, as a rule, they are connected to the ocean by one strait. For example, the Mediterranean Sea. These seas, in turn, are divided into isolated and semi-isolated.

Inland seas. These seas have virtually no communication with the ocean. Only a small and shallow strait can connect such a sea with the ocean. Example - Baltic Sea.

Interisland seas are seas around which there are many islands. For example, the Java Sea.

Marginal seas are most often located on the continental slope; they have very good communication with the ocean. Such seas usually have ocean currents. An example of such a sea is the Sea of ​​Okhotsk or the East China Sea.

Classification by coastline

The ruggedness of the sea coastline is the ratio of the length of this line to the area of ​​the continent. The seashore cannot be smooth; often bays, straits, etc. are formed on it. Depending on the ruggedness, seashores are:

  • Heavily rugged;
  • Lightly cut.

Heavily indented - this is a coast with capes, bays, peninsulas, islands.

Weakly indented - this is a coast with beaches, slanting, more even.

  • The bay is part of the sea; it extends far into the land, but at the same time has free water exchange.
  • An island is land that is completely washed by water.
  • A strait is a narrow piece of water that separates land and connects water basins.
  • A cape is a piece of land cut into the sea.
  • A spit is a strip of land on the seashore, it is formed due to the movement of debris by water. The braid is usually quite straight.
  • A bay is a small part of the sea, which is separated from open waters by parts of land.
  • The beach is an alluvial, flat shore.
  • A peninsula is a part of the mainland that extends far into the sea.

Classification by water salinity

According to the degree of salinity of the sea there are:

  • Highly salted;
  • Lightly salted.

Very salty seas are seas where the water is saltier than the ocean. This salinity is formed due to evaporation. More salty water flows to the lower layers, and less salty water rises to the top. This is how water exchange occurs.

Not very salty seas are seas that have less salinity than the ocean. And water exchange occurs as a result of the outflow of less saline water and the influx of more saline water.

If you are interested in the origin and name of various words, then in our article you will find a lot of interesting things.

St. Petersburg State Marine Technical University

Department of Ship Automation and Measurements

ABSTRACT

by discipline: “Subjects and objects of maritime law”

Subject: "Classification of oceans and seas"


PERFORMED BY: Shitov S.Yu.

CHECKED BY: Professor Alekseev A.V.

St. Petersburg, 2007

ABSTRACT


Report 16 pp., 2 figures, 4 tables, literature - 9 titles.

DIVISION OF THE EARTH'S SPACE, WORLD OCEAN, SEA, CLASSIFICATION SYSTEM OF THE GEOGRAPHICAL SOCIETY OF LONDON, OTTO KRUMMEL, VOEYKOV A.I.

The purpose of the work is to trace changes in the classifications of oceans and seas over time. The object of study is the classification of oceans and seas.


Dividing the spaces of the Earth. The sea occupies much more space than land. The world ocean is a body of water surrounding land. Sea - a part of the ocean more or less isolated by land, islands or elevated underwater terrain. Until recently, science was dominated by the old classical classification system, introduced in 1845 by the Royal Geographical Society of London. The world ocean was divided into 5 main parts: the Pacific Ocean (47%), the Atlantic Ocean (24%), the Indian Ocean (20%), the Southern Arctic Ocean (5%) and the Northern. Arctic Ocean (4%). Recently, a new, more rational classification by Krummel, introduced in 1878, has begun to prevail. Krummel rightly rejects the identification of a special Southern Arctic Ocean, because its boundaries cannot be drawn anywhere. The so-called Southern Arctic Ocean has to be distributed by longitude between three large oceans. The Arctic Ocean is excluded for another reason - it has the character of a sea surrounded by land rather than a real ocean, and, moreover, its depth, with few exceptions, is very shallow. Finally, in 1895, A.I. Voeikov proposed dividing the seas (adhering to Krummel’s view of the oceans proper) as follows: Mediterranean seas, island seas, transitional seas, bays or marginal seas. The Southern Arctic Ocean is 1/2 part of the Pacific Ocean, and 1/4 part of the Atlantic and Indian Ocean.


INTRODUCTION

1. Separation of the Earth’s spaces …………………………………………………

2. Classification system of the London Geographical Society ………….

3. Krümmel classification system……………………………………………

4. Voeikov’s classification system……………………………………………..

5. Scheme of classifications of oceans and seas……………………………..…………

CONCLUSION……………………………………………………………………..

BIBLIOGRAPHY…………………………………………………………


Introduction

Most of the surface of our planet is occupied by water. The problem of classifying water resources arises. In this abstract, three options for solving this problem will be considered: the classification system of the London Geographical Society, the classification system of Otto Krummel, the classification system of A.I. Voeykova.

1. Dividing the Earth's spaces

The surface of our planet Earth consists of continents and seas, or land and water, located so that land occupies only 26.5%, and sea 73.5% of the entire surface of the Earth. The sea occupies a much larger area than land, and there is an even greater difference between the two hemispheres. Thus, in the northern hemisphere, land occupies 40%, and in the southern hemisphere only 14%.

Table 1 shows the grouping of land and sea by individual latitudes. It shows that not only across the two hemispheres, but also across the parallels, they are distributed very unevenly.

Table 1 – Percentage of sushi


Hemispheres

northern

Land and water areas are grouped into separate units. The largest units of land are called continents, and the largest units of water are called oceans.

The World Ocean - the water space surrounding the land, occupies 71.7% (about 365 million sq. km.). The ocean is a large part of the world's oceans, possessing all the properties inherent in the world's oceans. Parts of the oceans adjacent to land are called seas, bays, bays, and straits.

The sea is a part of the ocean, more or less isolated by land, islands or elevations of underwater relief and differing from the open part of the ocean in hydrological and meteorological conditions: salinity, water temperature, currents, etc. The more closed the sea is by land, the more it differs from the ocean. Sometimes the sea can be an open part of the ocean or a large lake.

But the most superficial glance at the map is enough to indicate a significant difference between the grouping of land and seas. The parts of the first are truly and sharply separated from each other, that is, surrounded on all sides by seas, and in this regard we can say that there are only islands of different sizes, of which the largest are called continents, therefore, there is only a difference in names. The seas are all in continuous communication with each other and, moreover, with the exception of those that can be called Mediterranean and island, they are connected by wide and deep parts. As a result of this and the mobility of the liquid, constant communication is maintained between all the sea waters of the globe by a system of different movements, of which the more regular and constant ones are called currents. Marine water bodies are divided by size into oceans (the largest parts) and seas.

2. London Geographical Society classification system

Until recently, science was dominated by the old classical classification system, introduced in 1845 by the Royal Geographical Society of London. There were 5 different Oceans. The world ocean was divided into 5 main parts: the Pacific Ocean (47%), the Atlantic Ocean (24%), the Indian Ocean (20%), the Southern Arctic Ocean (5%) and the Northern. Arctic Ocean (4%).

The Pacific Ocean borders the Arctic Circle from the south, the meridian of Cape Horn and the shores of both Americas from the east, the Bering Strait from the north, and the shores of Asia, the Greater Sunda Islands, Australia, and Tasmania from the west. The Atlantic Ocean borders on the Arctic Circle from the south, on the east - on the meridian of the Cape of Good Hope, on the shores of Africa, Europe, on the north - on the Arctic Circle, on the west - on the shores of America and the meridian of Cape Horn to the Arctic Circle. The Indian Ocean is bordered from the south by the Arctic Circle, from the east by the meridian of Tasmania, the shores of this island, Australia and the Greater Sunda Islands, from the north by the shores of Asia, from the west by the shores of Africa and the meridian of the Cape of Good Hope to the Arctic Circle... Hopes to the Arctic Circle; The Arctic or Arctic Ocean borders the shores of Asia and North America, and where they are interrupted, then the Arctic Circle; The Antarctic or Southern Arctic borders in the north with the southern polar circle, and in the south with the shores of the Antarctic continent. These boundaries also included all parts of the oceans that more or less went deep into the continents, as long as they were in direct connection with them through straits. Such parts of the oceans are called seas and, according to the old classification, were recognized as of two types: internal and external. The first included seas connected to the oceans by narrow straits, for example: the Mediterranean, the Baltic, and the second - those adjacent to the oceans on their entire side, for example, the Arabian, Gulf of Guinea.


3 . Krümmel classification system

Recently, a new, more rational classification by Krummel, introduced in 1878, has begun to prevail. In this system, only the Pacific, Atlantic and Indian oceans are accepted as the most extensive, deep and having an independent system of currents. Krummel rightly rejects the identification of a special Southern Arctic Ocean, because its boundaries cannot be drawn anywhere. The further south you go to the high southern latitudes, the more the oceans expand and the percentage of land decreases. There are no natural boundaries here, and the so-called Southern Arctic Ocean has to be distributed by longitude between three large oceans. The Arctic Ocean is excluded for another reason - it has the character of a sea surrounded by land rather than a real ocean, and, moreover, its depth, with few exceptions, is very small; according to Krümmel's classification, this is one of his four Mediterranean seas.

The three other Mediterranean seas in this classification divide what Krümmel calls the northern and southern continents. The sea, usually called the Mediterranean, with the Marmara, Black and Azov, separates Europe from Africa and Asia, the sea between Asia and Australia, called the Asian-Australian Mediterranean Sea, separates these two continents; finally, the Gulf of Mexico and the Gulf of the Caribbean, which he calls the American Mediterranean Sea, separate the continents of North and South America. In addition to the oceans and Mediterranean seas, Krummel also receives the so-called outlying seas, which include, for example, the German Sea, the Gulf of California, the Sea of ​​Okhotsk, the East China Sea, the Japanese Sea, the Bering Sea and others. But it will be more convenient to recognize as Mediterranean seas only those that are separated from the oceans and marginal seas by relatively very narrow and shallow straits to such an extent that the entire system of equilibrium of their waters, temperature distribution, etc. are under very weak influence of the ocean. Thus, these real Mediterranean seas are, as it were, transitional to the large salt lakes, our Caspian and Aral, which are usually also given the name of seas. According to this classification, there are only seven Mediterranean seas on the globe, of which four form one common, i.e. interconnected, system, and are connected to the ocean only through the outermost of them. I mean the real so-called Mediterranean Sea with the Marmara, Black and Azov seas. This is the central and most typical Mediterranean sea on the globe. Then, to the North of it is the Baltic Sea, to the South - the Red Sea and the Persian Gulf. Note that the real Mediterranean seas are located only in the western part of the Old World and nowhere else. They are connected to the ocean not only by relatively narrow and shallow straits, but also by a few: the Mediterranean Sea by one, the Red Sea and the Persian Gulf by two, the Baltic by three.


4. Voeikov classification system

Finally, in 1895, A.I. Voeikov proposed dividing the seas (adhering to Krummel’s view of the oceans themselves) as follows: the Mediterranean seas should be recognized as spaces surrounded by 19/20 continents and connected to the oceans or other seas by straits, the width of which is not more than 1 km . for every 5000 sq. km. the total surface of the sea, provided that there are no more than 3 such straits; island - which are 1/5 limited to islands and are connected to the oceans or other seas by many straits, but provided that each is not wider than 300 km; transitional - seas limited on 2/3 of the surface by continents, and the rest connected to other waters by straits wider than 300 km; bays or marginal seas - in which the ratio of the width of the straits to their area is less than 1 km. for 10 sq. km. and the straits are not narrower than the sea itself. According to this classification there will be: Mediterranean - the Mediterranean and the seas connected to it, the Red Sea, the Persian Gulf, the Baltic; island - Asian-Australian, American Mediterranean, Japanese and Okhotsk Seas.; transitional - the Arctic Ocean, the Gulf of St. Lawrence, the Bering Sea, the East China Sea; bays - the Arabian Sea, the Bay of Bengal, the Bay of Biscay, the Gulf of California, the Gulf of Guinea, the German Sea, etc. Of course, each of the above classifications is not free from reproaches, but their very appearance indicates the progress of this issue.

Table 2 – Space of oceans and seas according to the classification of A.I. Voeykova

Name

Thousands of square kilometers

Oceans (with bays)

Transitional seas

Island seas

Mediterranean seas

Atlantic


North Arctic


Mediterranean (with Black, etc.)

Baltic


American Mediterranean



Beringovo


East Chinese


Okhotsk

Japanese


Asian-Australian


Indian


Persian Gulf


The Southern Arctic Ocean is 1/2 part of the Pacific Ocean, and 1/4 part of the Atlantic and Indian Ocean.

The space of oceans and seas according to the latest classification is shown in Table 2; but since the other two classifications are also found in scientific works, we present these data for both.

Table 3 – Space of oceans and seas according to the classification of the London Geographical Society


Million sq. km.

Million sq. geogr. miles

Taking the Pacific Ocean as a unit

Atlantic

Indian

Antarctic

Arctic

The entire water surface

For classification according to Krümmel's method, we present surfaces and volumes according to the last calculation of Carstens in 1894. This calculation does not agree with Krümmel's classification in only one way, namely, the Southern Arctic Ocean is not divided between three main ones; however, Krummel also gave its value in his previous calculations.

Table 4 – Space of oceans and seas according to Krummel’s classification


Average depths, in m.

Surface area, in sq. km.

Volume, in cubic meters km.

Greatest depths, in m.

Pacific Ocean

Indian Ocean

Atlantic Ocean

All oceans

Arctic Mediterranean Sea

Australian-Asian Mediterranean

American Mediterranean

Mediterranean Sea

Hudson Bay

Baltic Sea

Red sea

Persian Gulf

All Mediterranean seas

German Sea

British marginal seas

St. Lawrence Bay

Andaman Sea

East China Sea

Japanese Sea

Sea of ​​Okhotsk

Bering Sea

California Bay

All marginal seas

Atlantic Ocean with its seas

Indian Ocean and its seas

The Pacific Ocean with its seas

Southern Arctic Sea


In this table in the last column the greatest depths are given according to the latest research, and for the Southern Arctic Ocean the depth found

Rice. 1. Scheme of classifications of oceans and seas


Rice. 2. Map of planet Earth

Ross and in modern times accepted by Murray, editor of the works of the Challenger expedition.


5. Scheme of classifications of oceans and seas

In Fig. 1. shows a diagram of the classifications of oceans and seas in accordance with:

1. Classification of the London Geographical Society 1845

2. Classification by Krummel Otto 1878

3. Classification by Voeikov A.I. 1895

CONCLUSION


In this abstract, various ways of dividing the Earth's water space were considered. The presence of several classifications of oceans and seas suggests that it is difficult to propose an optimal classification the first time. The classifications discussed in this abstract may continue to undergo a number of changes and be supplemented, or a completely new classification will appear. This situation is possible because people’s ideas about the structure of our planet may change as a result of various scientific experiments and research.

BIBLIOGRAPHY

1. Gatsunaev N.K. Geographers and travelers: A brief biographical dictionary. – M. Ripol Classic, 2001 – 573 p.

2. Kezling A. B. Observatory - geographical atlas of the world. – M.: Uniintekh, 2004 – 180 p.

3. Pirozhnik I.I. Geography of the world's oceans. – M.: TetraSystems, 2006 – 320 p.

4. Pritula T.Yu. Physical geography of continents and oceans. – M.: Vlados, 2004 – 685 p.

5. Stowe D. Encyclopedia of the Oceans. – M.: World of Books, 2007 – 256 p.

6. #"#_ftnref1" name="_ftn1" title=""> Data are given according to the latest research by Tillo, “The average height of the continents and the depth of the seas,” in “Izv. I.R. Geographical Society,” 1889)


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Once a year, crowds of tourists flock to the South Korean Jindo archipelago: due to the increasing tides between its two islands, the waves recede on the sea - and a land road almost three kilometers long and forty meters wide opens, representing an analogue of the famous miracle of Moses described in the Old Testament . Tourists use this opportunity to walk along the exposed bottom, take pictures and collect shells.

Since seas appeared on our planet relatively recently, from 20 to 2 million years ago, they are considered young geological formations. The deepest reservoirs arose in places where large faults formed in the earth's crust as a result of the displacement of lithospheric plates. For example, the deepest sea in the world, the Philippine Sea, is considered so because of the trench located at its bottom, the depth of which exceeds 10.5 km, when the average depth of a sea reservoir is about 4 km.

Due to the fact that almost all marine bodies of water are located near the coast of the continent or are located inside the continent, and the speed of sea currents due to limited communication with the World Ocean is low, they differ from it in the level of salinity, depth, water structure, climate, topography, flora and fauna (the farther from the ocean, the more noticeable the difference).

Marine bodies of water may be part of another sea - in this case they are distinguished depending on the flora and fauna: endemics are often found among the inhabitants of the deep sea, as can be seen in the example of the Aegean, located on the outskirts of the Mediterranean Sea.

Salinity

An important characteristic of a sea body of water is its salinity, which they receive thanks to rivers that carry dissolved salts from the depths of our planet and carry them to the seas. True, their level of salinity differs significantly from each other. Thus, bodies of water with a high salt content (for example, the Red Sea is considered the saltiest sea in the world) have a higher level of salinity than in the ocean: thanks to the active action, it goes into the atmosphere, and the salt goes to the bottom, where it gradually accumulates.


But low-salinity seas have a lower level of salinity than in the World Ocean, since due to climatic conditions the water evaporates slowly, which makes it possible for it to escape through the straits (the freshest sea in the world is the Baltic).

Temperature

Up to a depth of two hundred meters, the sea temperature depends on the geographic latitude and time of year: in areas with a hot climate, the water temperature will range from + 25 to + 30 ° C, in polar latitudes it can drop to -1.8 ° C (it does not freeze only thanks to dissolved salts in sea water).

But at great depths, water temperature indicators are affected by currents; the deeper they are, the colder the water (the Philippine Sea, the deepest sea in the world, at its lowest point has a temperature of about zero degrees).

As for the coldest sea body of water in the world, it is considered the East Siberian Sea, which is part of the Arctic Ocean: it is almost always covered with ice, and the water temperature in its northern part remains virtually unchanged throughout the year and amounts to -1.8° C, and in the south in summer the sea can warm up to five degrees above zero.

Tourists are recommended to relax on the Red Sea coast. It is located between the Arabian Peninsula and Africa and is the warmest sea body of water in the world. In summer the water temperature is +27°C, in winter it does not drop below +20°C.

Sea waves

Despite the fact that sea bodies of water are characterized by rather weak currents, the water in them moves even when in clear weather the sea surface seems perfectly flat. But the waves of the sea still beat against the shore - quietly, weakly, barely noticeably, but they constantly advance on the coast and retreat. They appear due to the wind, and their size depends on the strength of the air flow, which comes into contact with the water and, through friction, creates pressure on the crests of the waves (the shallower the depth, the smaller the waves). If there is no wind at all, then there is a swell and waves imperceptibly advancing on the coast.


Also characteristic waves are seiches - standing waves that rise and fall in the same place. This phenomenon lasts from several minutes to tens of hours. Despite the fact that the average wave height is thirty centimeters, it can easily vary from a few millimeters to five meters (it all depends on the topography of the coast and the depth of the reservoir). Seiches are not as harmless as they seem at first glance, and are primarily dangerous for small ships, boats and even people on the coast: suddenly rising high waves can “drag” a person under water.

Classification of seas

It is interesting that scientists still have not been able to come to a consensus on how many seas exist on our planet, since there are bodies of water that are difficult to classify and classify as a sea, lake or bay. Therefore, the official definition is questionable - and everyone puts them in the category that suits him most.

According to the International Hydrological Organization, there are sixty-three seas on Earth. Some scientists question these data, pointing out that many small marine reservoirs that are part of larger ones are not taken into account here, and therefore there are much more reservoirs of this type and their number is approaching a hundred.

To convince opponents, a map of the seas is cited as an example (it should be noted that in this list, many bays also fall into the category of seas, for example, the Persian, Bengal, and Mexican).


According to these data, there are about thirty seas in the Pacific Ocean, thirteen in the Southern Ocean, eleven in the Arctic Ocean, and six in the Indian Ocean. The number of marine bodies of water in the Atlantic Ocean causes the greatest disagreement among scientists and their number ranges from sixteen to thirty.

One of the most popular classifications is the division of seas according to the degree of their isolation from the ocean:

  • Internal - located at a great distance from the ocean, have limited water exchange with it and are connected by one or several straits;
  • Marginal - located near the ocean coast, are part of it and are located on the shelf;
  • Interisland - are part of the World Ocean and are separated from it by a ring of islands, within which the rise of the relief slows down the water exchange of these seas with the ocean. An island in the sea or ocean is usually the top of a high underwater mountain or appears as a result of seismic activity (earthquakes, volcanic eruptions). Sometimes it is artificially created by people when they form an artificial island in the sea for their own needs (for example, during construction in the UAE).

Starting point

As a result of many years of observations, several centuries ago, scientists came to the conclusion that it is the level of the sea surface that is the ideal point from which to measure the height of objects both above and below it. Therefore, it was decided to consider it the absolute height, the zero reference point (in contrast, the relative height shows how higher or lower one point is relative to another).

It should be noted that altitude above sea level is a rather conventional concept, since our planet is not entirely round in shape and is slightly flattened at the poles. Due to the different salinity levels of the Atlantic and Pacific oceans and the constantly changing direction of air currents, the difference in height from the surface of the two oceans is about 20 cm.

For example, in Russia, the zero point is considered to be the mark of the Kronstadt footstock (a level gauge, which is a rod with divisions), which was installed in Kronstadt on the Baltic Sea coast.

But the depth and height in Western Europe are calculated using a level gauge installed in Amsterdam; the level of the Mediterranean Sea is calculated using a gauge installed on the coast of Marseille. Other continents also have their own reference level.

Sea vessels in human life

The sea significantly influenced the development of civilization: as soon as man built his first ship, he began to plow the sea in search of routes to new lands, make great geographical discoveries, discovering this or that continent or island in the sea, and develop trade, science, and art.

It is not surprising that he paid special attention to the development of maritime transport: throughout the history of mankind, ships have played an important role in the life of society. And even now, despite the huge number of alternative modes of transport, more than 60% of the world's transport turnover is carried out by ships.

Transporting cargo by ship is 40% cheaper (this is especially beneficial for small countries whose borders are by sea) than transporting it by rail. Recently, with the development of technology, ships began to move at a fairly decent speed and some of them are capable of accelerating to 100 km/h).

In addition, the depths of the sea conceal a huge amount of natural resources (for example, oil), which man has learned to extract and use. Since almost all oil fields are located in the sea, and some are many kilometers from the coast, it was with the help of ships that people were able to reach minerals.

Thanks to ships, people were able to develop fishing: about 90% of the catch is caught in the seas and oceans (most fish are caught in the northern hemisphere). Unfortunately, for many fishermen, fishing is a real hunt, and therefore is often carried out uncontrolled, which leads to the disappearance of many rare species of marine life. There is hope that this process can be brought under control and poaching will be replaced by rational forms of fishing.