Related Research Articles
An ocean current is a continuous, directed movement of sea water generated by a number of forces acting upon the water, including wind, the Coriolis effect, breaking waves, cabbeling, and temperature and salinity differences. Depth contours, shoreline configurations, and interactions with other currents influence a current's direction and strength. Ocean currents are primarily horizontal water movements.
Physical oceanography is the study of physical conditions and physical processes within the ocean, especially the motions and physical properties of ocean waters.
The Cromwell Current is an eastward-flowing subsurface current that extends the length of the equator in the Pacific Ocean.
The Agulhas Current is the western boundary current of the southwest Indian Ocean. It flows south along the east coast of Africa from 27°S to 40°S. It is narrow, swift and strong. It is suggested that it is the largest western boundary current in the world ocean, with an estimated net transport of 70 sverdrups, as western boundary currents at comparable latitudes transport less — Brazil Current, Gulf Stream, Kuroshio.
In oceanography, a gyre is any large system of circulating ocean currents, particularly those involved with large wind movements. Gyres are caused by the Coriolis effect; planetary vorticity, horizontal friction and vertical friction determine the circulatory patterns from the wind stress curl (torque).
Townsend Cromwell was an oceanographer who discovered the Cromwell current while researching drifting in the equatorial region of the Pacific Ocean. He died in an airplane crash on 2 June 1958. The accident, also fatal to the American fisheries research biologist Bell M. Shimada, occurred near Guadalajara, Mexico, as the men were en route to join the Scot Expedition at Acapulco. Cromwell was Senior Scientist with the Inter-American Tropical Tuna Commission and Research Associate at Scripps Institution of Oceanography, La Jolla, California. His field of work was the physical environment and its relation to fisheries. He became a weather officer in the United States Army Air Forces during World War II. After receiving a B.A. degree from University of California in 1947, he returned to La Jolla, his boyhood home, as a student at Scripps, receiving an M.S. degree in oceanography from the University of California in 1949. At Scripps he was strongly influenced by the oceanographer H. U. Sverdrup.
The North Equatorial Current (NEC) is a westward wind-driven current mostly located near the equator, but the location varies from different oceans. The NEC in the Pacific and the Atlantic is about 5°-20°N, while the NEC in the Indian Ocean is very close to the equator. It ranges from the sea surface down to 400 m in the western Pacific.
The Equatorial Counter Current is an eastward flowing, wind-driven current which extends to depths of 100–150 metres (330–490 ft) in the Atlantic, Indian, and Pacific Oceans. More often called the North Equatorial Countercurrent (NECC), this current flows west-to-east at about 3-10°N in the Atlantic, Indian Ocean and Pacific basins, between the North Equatorial Current (NEC) and the South Equatorial Current (SEC). The NECC is not to be confused with the Equatorial Undercurrent (EUC) that flows eastward along the equator at depths around 200 metres (660 ft) in the western Pacific rising to 100 metres (330 ft) in the eastern Pacific.
The Romanche Trench, also called the Romanche Furrow or Romanche Gap, is the third deepest of the major trenches of the Atlantic Ocean, after the Puerto Rico Trench and the South Sandwich Trench. It bisects the Mid-Atlantic Ridge (MAR) just north of the equator at the narrowest part of the Atlantic between Brazil and West Africa, extending from 2°N to 2°S and from 16°W to 20°W. The trench has been formed by the actions of the Romanche Fracture Zone, a portion of which is an active transform boundary offsetting sections of the Mid-Atlantic Ridge.
The North Pacific Gyre (NPG) or North Pacific Subtropical Gyre (NPSG), located in the northern Pacific Ocean, is one of the five major oceanic gyres. This gyre covers most of the northern Pacific Ocean. It is the largest ecosystem on Earth, located between the equator and 50° N latitude, and comprising 20 million square kilometers. The gyre has a clockwise circular pattern and is formed by four prevailing ocean currents: the North Pacific Current to the north, the California Current to the east, the North Equatorial Current to the south, and the Kuroshio Current to the west. It is the site of an unusually intense collection of human-created marine debris, known as the Great Pacific Garbage Patch.
The North Brazil Current (NBC) is a warm water ocean current that is part of the southwestern North Atlantic Gyre. It begins when the westward moving Atlantic South Equatorial Current splits in half and flows northwestward, following the coastline of north Brazil. It ends at the border of Brazil and Guiana, where it is renamed the Guiana Current. It is predominantly a salt water current, but it does help transport fresh water from the Amazon River northward.
The Atlantic meridional overturning circulation (AMOC) is the zonally integrated component of surface and deep currents in the Atlantic Ocean. It is characterized by a northward flow of warm, salty water in the upper layers of the Atlantic, and a southward flow of colder, deep waters that are part of the thermohaline circulation. These "limbs" are linked by regions of overturning in the Nordic and Labrador Seas and the Southern Ocean. The AMOC is an important component of the Earth's climate system, and is a result of both atmospheric and thermohaline drivers.
Soviet and Russian staffed drifting ice stations are research stations built on the ice of the high latitudes of the Arctic Ocean. They are important contributors to exploration of the Arctic. The stations are named North Pole, followed by an ordinal number: North Pole-1, etc.
In physical oceanography and fluid dynamics, the wind stress is the shear stress exerted by the wind on the surface of large bodies of water – such as oceans, seas, estuaries and lakes. Stress is the quantity that describes the magnitude of a force that is causing a deformation of an object. Therefore, stress is defined as the force per unit area and its SI unit is the Pascal. When the deforming force acts parallel to the object's surface, this force is called a shear force and the stress it causes is called a shear stress. When wind is blowing over a water surface, the wind applies a wind force on the water surface. The wind stress is the component of this wind force that is parallel to the surface per unit area. Also, the wind stress can be described as the flux of horizontal momentum applied by the wind on the water surface. The wind stress causes a deformation of the water body whereby wind waves are generated. Also, the wind stress drives ocean currents and is therefore an important driver of the large-scale ocean circulation. The wind stress is affected by the wind speed, the shape of the wind waves and the atmospheric stratification. It is one of the components of the air–sea interaction, with others being the atmospheric pressure on the water surface, as well as the exchange of energy and mass between the water and the atmosphere.
The sea, connected as the world ocean or simply the ocean, is the body of salty water that covers approximately 71 percent of the Earth's surface. The word sea is also used to denote second-order sections of the sea, such as the Mediterranean Sea, as well as certain large, entirely landlocked, saltwater lakes, such as the Caspian Sea.
The sailing vessel Mandalay is a three-masted schooner measuring 202 ft (62 m) at the waterline, with an almost indestructible Danish wrought iron hull. It was built as the private yacht Hussar (IV), and would later become the research vessel Vema, one of the world's most productive oceanographic research vessels. The ship currently sails as the cruising yacht Mandalay in the Caribbean.
The environmental effects of shipping include air pollution, water pollution, acoustic, and oil pollution. Ships are responsible for more than 18 percent of some air pollutants.
The Somali Current is a cold ocean boundary current that runs along the coast of Somalia and Oman in the Western Indian Ocean and is analogous to the Gulf Stream in the Atlantic Ocean. This current is heavily influenced by the monsoons and is the only major upwelling system that occurs on a western boundary of an ocean. The water that is upwelled by the current merges with another upwelling system, creating one of the most productive ecosystems in the ocean.
The POLYGON experiment was a pioneer experiment in oceanography conducted in middle of the Atlantic Ocean during the 1970s. The experiment, led by Leonid Brekhovskikh, was the first to establish the existence of so-called "mesoscale eddies", eddies at the 100-km and 100-day scale, which triggered the "mesoscale revolution". The existence of mesoscale eddies were predicted by Henry Stommel in the 1960s, but there was no way to observe them with traditional sampling methods.
A Wind generated current is a flow in a body of water that is generated by wind friction on its surface. Wind can generate surface currents on water bodies of any size. The depth and strength of the current depend on the wind strength and duration, and on friction and viscosity losses, but are limited to about 400 m depth by the mechanism, and to lesser depths where the water is shallower. The direction of flow is influenced by the Coriolis effect, and is offset to the right of the wind direction in the Northern Hemisphere, and to the left in the Southern Hemisphere. A wind current can induce secondary water flow in the form of upwelling and downwelling, geostrophic flow, and western boundary currents.
References
- 1 2 Kolesnikov, A.G. (1966). Techenie Lomonosova (in Russian). Kiev: Naukova dumka. p. 4.
- ↑ "Cruises of the MHI's Research Vessels". Marine Hydrophysical Institute. Archived from the original on 2007-11-08. Retrieved 2008-04-21.
- ↑ Russian Marine Expeditionary Investigations of the World Ocean. International Ocean Atlas and Information Series. Silver Spring, MD: Diane Publishing Co. December 2002. p. 29. ISBN 1-4289-6114-3 . Retrieved 2008-04-21.
- ↑ Gouriou, Y. "3.3.2. Subsurface Circulation". Resources, fishing and biology of the tropical tunas of the Eastern Central Atlantic. FAO . Retrieved 2008-04-21.
- ↑ D. Bonhoure; et al. "The South Equatorial Sys Current". Surface Currents in the Atlantic Ocean. CIMAS . Retrieved 2008-04-21.
Ocean currents and gyres | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Currents |
| ||||||||||
| Gyres |
| ||||||||||
| Related | |||||||||||
 | This article about a specific ocean current is a stub. You can help Wikipedia by expanding it. |