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Mindanao Eddy
The Mindanao Eddy (7°N, 128°E) is a semi-permanent cold-ring eddy formed in the retroflection area of the Mindanao Current. The Mindanao Eddy is bordered to the north by the North Equatorial Current and to the south by the North Equatorial Counter Current. The eddy has a diameter of 250 km and a cyclonic circulation. The Mindanao Eddy has been identified as potential grounds for fisheries due to upwelling Upwelling is an oceanographic phenomenon that involves wind-driven motion of dense, cooler, and usually nutrient-rich water from deep water towards the ocean surface. It replaces the warmer and usually nutrient-depleted surface water. The nutr ....Primavera, K.H., Jacinto, G.S., San Diego-McGlon, M.L., Villanoy, C.L. Water Stability. Nutrient Flux, and Chlorophyll-a Distribution in the Mindanao Eddy. Natural Science. 8: 163-173. References Additional sources * {{cite journal, date=5 December 2003, title=Observed features of the Halmahera and Mindanao Eddies, j ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eddy (fluid Dynamics)
In fluid dynamics, an eddy is the swirling of a fluid and the reverse current created when the fluid is in a turbulent flow regime. The moving fluid creates a space devoid of downstream-flowing fluid on the downstream side of the object. Fluid behind the obstacle flows into the void creating a swirl of fluid on each edge of the obstacle, followed by a short reverse flow of fluid behind the obstacle flowing upstream, toward the back of the obstacle. This phenomenon is naturally observed behind large emergent rocks in swift-flowing rivers. An eddy is a movement of fluid that deviates from the general flow of the fluid. An example for an eddy is a vortex which produces such deviation. However, there are other types of eddies that are not simple vortices. For example, a Rossby wave is an eddy which is an undulation that is a deviation from mean flow, but doesn't have the local closed streamlines of a vortex. Swirl and eddies in engineering The propensity of a fluid to swirl is used ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mindanao Current
The Mindanao Current (MC) is a southward current in the western Pacific Ocean that transports mass and freshwater between ocean basins. It is a low-latitude western boundary current that follows the eastern coast of the Philippine island group and its namesake, Mindanao. The MC forms from the North Equatorial Current (NEC) that flows from east to west between 10-20°N. As it travels west, the NEC reaches its western limit: the coast of the Philippines. Once it encounters shallower waters near land, it “splits” into two branches: one moves northward and becomes the Kuroshio current and one moves southward and becomes the Mindanao Current. The process of splitting is called a bifurcation. The Mindanao Current flows towards the equator and is most intense near the surface, reaching maximum speeds of 1.3 ms^. It can be observed until depths of 1000 m near the Philippine coast and extends until 350 km offshore. The MC transports climatic signals and in doing so, influences the reg ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
North Equatorial Current
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 NEC is driven by the north-hemisphere easterly trade wind. In couple with NEC, there is another current called South Equatorial Current ( SEC), generated by the easterly trade wind in the southern hemisphere. Despite the well-coupled name of the two equatorial currents, the distribution of the NEC and the SEC is not in symmetry at the equator, but slightly northward to the equator. This asymmetric distribution is aligned to the location of the Intertropical Convergence Zone (ITCZ), which is the area that the northeast and the southeast trade wind converge. Related processes The Equatorial Counter Current The NEC and the SEC will gen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
North Equatorial Countercurrent
The Equatorial Counter Current is an eastward flowing, wind-driven current which extends to depths of 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 in the western Pacific rising to in the eastern Pacific. In the Indian Ocean, circulation is dominated by the impact of the reversing Asian monsoon winds. As such, the current tends to reverse hemispheres seasonally in that basin. The NECC has a pronounced seasonal cycle in the Atlantic and Pacific, reaching maximum strength in late boreal summer and fall and minimum strength in late boreal winter and spring. Furthermore, the NECC in the Atlantic disappears in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyclonic
In meteorology, a cyclone () is a large air mass that rotates around a strong center of low atmospheric pressure, counterclockwise in the Northern Hemisphere and clockwise in the Southern Hemisphere as viewed from above (opposite to an anticyclone). Cyclones are characterized by inward-spiraling winds that rotate about a zone of low pressure. The largest low-pressure systems are polar vortices and extratropical cyclones of the largest scale (the synoptic scale). Warm-core cyclones such as tropical cyclones and subtropical cyclones also lie within the synoptic scale. Mesocyclones, tornadoes, and dust devils lie within smaller mesoscale. Upper level cyclones can exist without the presence of a surface low, and can pinch off from the base of the tropical upper tropospheric trough during the summer months in the Northern Hemisphere. Cyclones have also been seen on extraterrestrial planets, such as Mars, Jupiter, and Neptune. Cyclogenesis is the process of cyclone formation and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Upwelling
Upwelling is an oceanographic phenomenon that involves wind-driven motion of dense, cooler, and usually nutrient-rich water from deep water towards the ocean surface. It replaces the warmer and usually nutrient-depleted surface water. The nutrient-rich upwelled water stimulates the growth and reproduction of primary producers such as phytoplankton. The biomass of phytoplankton and the presence of cool water in those regions allow upwelling zones to be identified by cool sea surface temperatures (SST) and high concentrations of chlorophyll-a. The increased availability of nutrients in upwelling regions results in high levels of primary production and thus fishery production. Approximately 25% of the total global marine fish catches come from five upwellings, which occupy only 5% of the total ocean area.Jennings, S., Kaiser, M.J., Reynolds, J.D. (2001) "Marine Fisheries Ecology." Oxford: Blackwell Science Ltd. Upwellings that are driven by coastal currents or diverging open oc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Whirlpools
A whirlpool is a body of rotating water produced by opposing currents or a current running into an obstacle. Small whirlpools form when a bath or a sink is draining. More powerful ones formed in seas or oceans may be called maelstroms ( ). ''Vortex'' is the proper term for a whirlpool that has a downdraft. In narrow ocean straits with fast flowing water, whirlpools are often caused by tides. Many stories tell of ships being sucked into a maelstrom, although only smaller craft are actually in danger. Smaller whirlpools appear at river rapids and can be observed downstream of artificial structures such as weirs and dams. Large cataracts, such as Niagara Falls, produce strong whirlpools. Notable whirlpools Saltstraumen Saltstraumen is a narrow strait located close to the Arctic Circle, south-east of the city of Bodø, Norway. It has one of the strongest tidal currents in the world. Whirlpools up to in diameter and in depth are formed when the current is at its strongest. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
