What is the sea?
Many of us have been to the sea and know how beautiful it is in summer to relax on the beach, from time to time swimming in the water. 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.
The sea is a certain part of the ocean, from which it is separated by land. Simply put, the sea is a lot of salt water. The sea is of a different color, and the color depends on where it is located in the world.
There are the following classifications of the seas:
- Water temperature;
- By the irregularity of the shoreline;
- According to the degree of isolation from the ocean;
- Across the oceans;
- According to the degree of salinity.
There are sixty-three seas on our planet. Eleven of them belong to the Indian Ocean (Timor Sea, Arabian Sea), eleven - to the Arctic Ocean (Barents Sea, Greenland Sea), sixteen seas - to the Atlantic Sea (Marmara Sea, Irish Sea, Caribbean Sea) and twenty-five - to Quiet (Japan Sea, Aki Sea, Coral Sea, Sea of Okhotsk). More information about all the seas can be found in our article How many seas on Earth.
Water temperature classification
There is also a division of the seas according to the temperature of their waters.
So, the seas are:
- 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, water temperatures average seventeen degrees above zero.
And in tropical seas, temperatures can be twenty-four to twenty-seven degrees above zero.
The temperature of the seas depends on the arrival and consumption of heat. The sea receives heat from solar radiation, and consumes this heat to exchange with the atmosphere and evaporation of water.
Classification by degree of isolation from the ocean
- Inter island;
Intercontinental Seas. Land almost completely surrounds them, and with the ocean they are connected, as a rule, one strait. For example, the Mediterranean Sea. These seas, in turn, are divided into insulated and semi-insulated.
Inland seas. These seas practically do not communicate with the ocean. Only a small and shallow strait can connect such a sea with the ocean. An example is the Baltic Sea.
Inter-island seas are seas, around which many islands are located. For example, the Java Sea.
The marginal seas are most often located on the continental slope, they have very good communication with the ocean. In such seas there are usually ocean currents. An example of such a sea is the Sea of Okhotsk or the East China Sea.
The rugged coastline of the sea is the ratio of the length of this line to the area of the mainland. The seacoast cannot be smooth, often bays, straits, etc. are formed on it. Depending on the irregularity, the sea shores are:
- Heavily cut;
- Weakly cut.
Heavily cut is a coast with capes, bays, peninsulas, islands.
Low cut - it is a beach with beaches, oblique, more even.
- The bay is a part of the sea, it goes far into the land, but at the same time it has free water exchange.
- The island is a land that is completely washed by water.
- The strait is a narrow part of the water that divides the land and connects the water basins.
- Cape - is part of the land, embedded in the sea.
- Spit is a strip of land on the seashore, it is formed due to the movement of detrital material by water. Spit is usually quite flat.
- The bay is a small part of the sea, which is separated from the open waters by parts of land.
- The beach is an alluvial, flat beach.
- The peninsula is a part of the continent that is far out into the sea.
Water salinity classification
According to the degree of salinity of the sea there are:
- Strong salted;
- Lightly salted.
Very salty seas - these are the seas in which the water is more salty than in the ocean. Such salinity is formed due to evaporation. More salty water flows into the lower layers, and less salty water rises. So is the water exchange.
Not very salty seas are seas whose salinity is less than in the ocean. And water exchange occurs as a result of the outflow of less saline water and the influx of more saline water.
So, we learned what the sea is and what kind of seas there are, how they differ. As you can see, the seas are very different.