What are Ocean Currents?
The steady movement of the ocean’s surface water in a prevailing direction is known as the ocean currents. There are various factors that contribute to the formation of ocean currents. These factors include the wind, temperature, tides, breaking of waves, and underground activities such as earthquakes.
Ocean currents occur due to the movement of ocean water because of the rotation of the earth which is known as the Coriolis effect, water density, gravity, the sun, and the wind. These factors determine the shape, size, speed, and direction of the ocean currents.
Types of Ocean Currents
There are two types of ocean currents:
- Horizontal currents
- Vertical currents
Horizontal Currents
- Surface currents: The currents that occur on the top layer of the ocean are known as the surface currents. They are driven by the wind. The surface currents are responsible for the distribution of the heat at a planetary scale.
- Deep-water currents: The currents that occur deep inside the ocean are known as deep-water currents. The wind has no role to play when deep-water currents are considered. The factors such as density of ocean water, temperature, and the salinity of the water help in the formation of deep-water currents.
Vertical Currents
- Upwelling: These currents move from deep inside the ocean to the surface. They are responsible for bringing the organic matter from below the ocean. The upwelling currents help in the fixation of the nitrogen and phosphates that help in the blooming of algae and other plants.
- Downwelling: These currents push the materials from the surface to deep inside the ocean. The pressure from the ocean water pushes the materials downwards. This vertical current is important because it helps in pushing the dissolved oxygen that helps in the decomposition of organic matter.
Causes of Ocean Currents
The following factors cause the ocean currents:
- Coriolis effect: We know that the Coriolis effect is the study of the dynamics of the atmosphere. However, in the hydrosphere, it affects the rotation of the ocean currents.
- Gravity: Gravity helps in pulling the items towards the surface of the earth. The water gets piled up in the direction of the wind.
- Wind: The currents on the surface of the ocean are caused by the winds. The ocean currents are formed by the wind, which is responsible for the redistribution of the ocean water depending on the density and temperature.
Effects of Ocean Currents
The following things occur due to the effects of ocean currents:
- Formation of rain: Evaporation takes place because of warm currents, which results in rain. This is commonly seen in coastal areas. For example, the Western parts of Europe experience rain throughout the year.
- Destruction of marine wildlife: Marine wildlife such as planktons get affected by the strong currents.
- Helping with the life cycle: The strong upwelling currents help in pumping nitrogen and phosphates up from the deep sea. This results in the blooming of algae and other plants. This is seen in Antarctica. Stay tuned to understand how ocean currents help in maintaining the climate and how important they are.