ocean currents is the seasonal seawater movement generated by forces acting on this average stream, such as wind, Coriolis effects, breaking waves, cabbing, temperature and salinity differences, whereas tidal currents are caused by gravitational pull Sun and moon. Contour depth, coastline configuration, and interaction with other currents influence the direction and strength of the current. Ocean currents are primarily horizontal water movements.
Ocean currents flow for great distances, and together, creating a global conveyor belt that plays a dominant role in determining the climate of many regions of the Earth. More specifically, ocean currents affect the temperature of the region in which they travel. For example, the warm currents that run along the more temperate beaches are increasing the temperature of the area by warming the sea breeze blowing on it. Perhaps the most striking example is the Gulf Stream, which makes northwestern Europe much more temperate than other areas of the same latitude. Another example is Lima, Peru, where the climate is cooler, becoming sub-tropical, rather than the tropical latitudes in which the area is located, due to the Humboldt Flow effect.
Video Ocean current
Function
The surface ocean currents are sometimes driven by the wind and develop their typical clockwise spirals in the northern hemisphere and clockwise rotation in the southern hemisphere due to the wind pressure generated. In this wind-driven stream, the Ekman spiral effect produces a current flowing at an angle toward the driving wind. In addition, the surface area of ​​the ocean currents moves somewhat with the seasons; this is most prominent in the equatorial currents.
The deep sea basin generally has a non-symmetrical surface current, where the east easterly branch equatorward extends and spreads while the west poleward flowing branch is very narrow. This western boundary (where the Gulf Stream is an example) is a consequence of Earth's rotation.
The deep ocean currents are driven by density and temperature gradients. Thermohaline circulation is also known as the ocean conveyor belt (which refers to ocean currents supplied by deep ocean currents). This stream, called an underwater river, flows beneath the surface of the ocean and is hidden from direct detection. Where significant vertical movement of ocean currents is observed, this is known as upwelling and downwelling. The deep ocean currents are currently being researched using an underwater robot fleet called Argo.
Surface currents form only 8% of all water in the oceans, generally limited to 400 m (1,300 ft) of seawater, and are separated from lower regions by varying temperatures and salinity that affect water density, which, in turn, define each oceans region. Since the movement of deep water in the ocean basin is caused by density-driven forces and gravity, deep waters sink into deep ocean basins at high latitudes where temperatures are cool enough to cause increased density.
Sea currents are measured in sverdrup (sv), where 1 sv is equivalent to the volume flow rate of 1,000,000 m 3 (35,000,000 cuÃ, ft) per second.
Surface currents are found at sea level, and are driven by large-scale wind currents. They are directly affected by wind - the Coriolis effect plays a role in their behavior.
Maps Ocean current
Thermohaline circulation
The thermohaline circulation is part of a large-scale ocean circulation driven by a global density gradient created by surface heat and freshwater flux. The adjective thermohaline comes from thermo - refers to the temperature and -haline which refers to the salt content, -the same determines the density of seawater. Wind-driven surface currents (such as the Gulf Stream) travel from the equatorial Atlantic Ocean, cool the journey, and eventually sink at high latitudes (forming the Deep Water Deep North). This dense water then flows into the ocean basin. While the largest part is in the Southern Ocean, the oldest waters (with a transit time of about 1000 years) are in the North Pacific. Extensive mixing therefore takes place between the ocean basins, reducing the differences between them and making the Earth's oceans into a global system. In its journey, water masses transport energy (in the form of heat) and matter (solids, solutes and gases) around the world. Thus, the state of circulation has a major impact on Earth's climate. Thermohaline circulation is sometimes called the ocean conveyor belt, the great ocean conveyor, or the global conveyor belt. Sometimes, it is not appropriately used to refer to meridional overturning circulation, MOC .
Importance
Knowledge of surface ocean currents is critical in reducing shipping costs, since traveling with them reduces fuel costs. In this era of wind-sailing vessels, knowledge of wind patterns and ocean currents is even more important. A good example of this is Agulhas Current, which has long prevented Portuguese sailors from reaching India. In recent years, sailing competitors around the world are using surface currents well to build and maintain speed. Ocean currents are also very important in the spread of many life forms. An example is the life cycle of Eel Europe.
Ocean currents are very important in marine waste studies, and vice versa. This current also affects the temperature around the world. For example, ocean currents carrying warm water north of the Atlantic to northwest Europe are also cumulatively and slowly blocking ice formed along the coast, which will also block ships from entering and exiting the waterways and inland ports, hence the ocean currents play a role determine. in influencing the climate of the region in which they flow. The cold ocean currents flowing from the polar regions and sub-poles carry many of the most important plankton for the survival of some of the major marine species in marine ecosystems. Since plankton is fish food, abundant fish populations often live where the current is in effect.
Ocean currents can also be used for marine power plants, with areas outside Japan, Florida and Hawaii being considered for pilot projects.
OSCAR: Global sea level data set almost realtime
OSCAR A near-real time global ocean surface website describes projects and links to data validation and data downloads.
Source of the article : Wikipedia
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