Marine Currents (Meaning and Explanation)

We explain what marine currents are and the types that exist. Also, the causes of its formation and the main marine currents.

What are ocean currents?

It is called sea currents or ocean currents to a type of characteristic movement of the waters that make up the largest oceans and seas, and which are due to a multitude of factors, both the earth's rotation, the winds and the location of the continents.

sea currents often involve both cold and warm water masses which connect various climatic strips of the globe, traveling both surface and underwater:

The warm currents. They are surface waters that originate in the oceans of the intertropical zone and migrate from the eastern coasts of the continents to the middle and high latitudes, against the Earth's rotation and only in the northern hemisphere.
The cold currents. They are waters of low temperature and great depth, which start from the intertropical or subtropical zone, and compensate for the effect of warm waters when they reach the western coasts of the continents. They are particular to the Arctic regions, since in the Antarctic zone there is only a circular current around the pole.

The constant movement of these marine currents throughout the world allows maintaining an energy and caloric cycle on the planet which results in a set of more or less fixed climates in certain regions, such as dry climates on the western coasts of the intertropical or subtropical zone, and warmer and more humid climates on the western coasts of the continents in the middle latitudes. and tall. The same thing happens with salinity levels in ocean waters. This joint cycle is known as Circulation thermohaline world.

Types of ocean currents

We can talk about the following types of currents, according to their characteristics:

Ocean currents. They present a constant movement generated by the Earth's rotation, generally in an east-west direction in the intertropical zone, or in the opposite direction in the middle or high latitudes.
Tidal currents. Periodic currents with a daily cycle, which produce the attraction of the Moon and the Sun on the surface of the waters, that is, in warm waters. They move enormous amounts of water from the northern to the southern hemisphere and vice versa.
Wave currents. Produced by winds, especially storms or hurricanes, they take place on the water surface and have a limited impact.
Coastal drift currents. They are due to the encounter of the currents with the outline of the relief of the coasts, which forces them to modify their orientation or direction.
Density currents. Those that originate in the contact zone between two masses of water with different density, such as those that are more and less saline, or more and less warm. They usually occur in straits between different seas and oceans, along the equatorial axis, or along the Arctic Circle.

Causes of ocean currents

The three most important physical causes of ocean currents are:

Earth movements. Both the translation and the rotation of the planet cause constant movements of the water masses, although in many cases they move in the opposite direction to the rotation of the Earth.
The planetary winds. It is not true that the winds directly cause the tides, but they do contribute to it, by moving not only surface waters (as in waves), but also by mobilizing the atmosphere to circulate the heat energy of the environment, which has an impact on the water.
The emergence of cold waters. Deep ocean waters are cold because they are denser and have less energy. These waters rise to the surface in specific areas of the intertropical zone, pushing the warm waters in their wake.

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Main marine currents of the world

The main known marine currents are, according to the Ocean:

Arctic Ocean.
- West Greenland Current.
- East Greenland Current.
- Norwegian Current.
Atlantic Ocean.
- Antilles Current.
- North Atlantic Current.
- South Atlantic Current.
- Benguela Current.
- Brazilian Current.
- Cape Horn Current.
- Canary Current.
- Caribbean Current.
- North Equatorial Current.
- South Equatorial Current.
- Gulf Stream.
- Guinea Current.
- Labrador Current.
- Madagascar Current.
- Falklands Current.
- Northern Brazilian Current.
- Portuguese Current.
- Spitzbergen Current.
Pacific Ocean.
- Alaska Current.
- Aleutian Current.
- East Australian Current.
- California Current.
- Cromwell current.
- Humboldt Current.
- Kamchatka Current.
- Kuroshio or Japan Current.
- Mindanao Current.
- Child stream.
- Oyashio Current.
- North Pacific Current.
Indian Ocean.
- Needle Stream.
- Western Australian Current.
- South Equatorial Current.
- East Madagascar Current.
- Leeuwin current.
- Madagascar Current.
- Monsoon Current.
- Mozambique Current.
- Somali Current.
Antarctic Ocean.
- Antarctic Current.
- Antarctic Circumpolar Current.
- Wedell turn.