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Founded in 1876, Texas A&M University is a U.S. public and comprehensive university offering a wide variety of academic programs far beyond its original label of agricultural and mechanical trainings. It is one of the few institutions holding triple federal designations as a land-, sea- and ...
A subpolar cyclonic circulation in the northeast Pacific associated with the Aleutian low. The primary currents consist of a broad eastern boundary current flowing north, condensing into a narrow western boundary flow in the apex of the gyre and proceeding west-southwest along the Aleutian Peninsula as the Alaskan Stream.
Industry:Earth science
Flat areas of the ocean basin floor which slope less than 1 part in 1000. These were formed by turbidity currents which covered the preexisting topography. Most abyssal plains are located between the base of the continental rise and the abyssal hills. The remainder are trench abyssal plains that lie in the bottom of deep-sea trenches. This latter type traps all sediment from turbidity currents and prevents abyssal plains from forming further seaward, e.g. much of the Pacific Ocean floor.
Industry:Earth science
A filtering approximation for the equations of motion that eliminates sound waves by assuming that the flow has velocities and phase speeds much smaller than the speed of sound. In its purest form, it requires that the reference state be isentropic as well as hydrostatic, although in practice the reference state is often taken to be nonisentropic which can have deleterious effects on the energy conservation properties of the full set of equations. The anelastic approximation is one of the set of approximations used for the somewhat similar Boussinesq approximation.
Industry:Earth science
The processes that involve the transfer of energy, matter, and momentum between the atmosphere and the ocean. The is one of the least well understood areas of physical oceanography, with the theory inadequate and the data sparse. Specific areas with glaring gaps include the interaction of the wind and surface waves, the parameterization of subgrid scale processes in large-scale circulation models, and the transfer of gases across the air-sea interfaces.
Industry:Earth science
In physical oceanography, a water mass in the Antarctic Zone of the Southern Ocean AASW is found in the upper 200 m south of the Polar Front (PF) and is cold, fresh, and high in oxygen and nutrients relative to the subantarctic surface waters, although it is high in nutrients compared to underyling waters. The most easily distinguishable characteristics of AASW in summer sections is a intense temperature minimum at about 200 m that marks the base of the winter mixed layer. The water around this minimum is also commonly known as Winter Water, and ranges from 50 m deep in the Weddell Gyre to nearly 1000 m just north of the PF. It is characterized by very low temperatures ranging down to the freezing point of -1. 9° C and low salinities as the result of ice melting in the summer in the upper 100-250 m of the water column.
Industry:Earth science
A joint program between WOCE and NOAA's ACCP designed to increase understanding of the meridional overturning circulation (MOC) of the Atlantic Ocean and the overlying atmosphere at interannual and longer time scales. The goals of ACCE were:
* to provide a quantitative 4-D observational description of the pathways and material property fluxes of the MOC within the North Atlantic Ocean that vary on time scales from interannual to at least decadal;
* to improve understanding and modeling of the relationships between the rates and natural variability of the MOC, internal ocean properties, SST, and the variability of the overlying atmosphere; and
* to identify and initiate measurements to be continued beyond the ACCE observational period to monitor the variability of important elements of the MOC and its relation to global climate variability.
Industry:Earth science
A type of water in the seas surrounding Antarctica with temperatures ranging from 0 to -0. 8° C, salinities from 34. 6 to 34. 7, and a density near 27. 88. ABW is formed in the Weddell and Ross Seas. This is the densest water in the free ocean, with the only denser waters being found in regional sill basins such as the Norwegian Sea or the Mediterranean. It is overlain by Antarctic Circumpolar Water (AACW) at a depth of 1000 to 2000 m and overlies Weddell Sea Bottom Water (WSBW) in some locations.
The flow of AABW in the tropical Atlantic is described by Rhein et al. (1998) as:
About one-third of the northward flowing AABW at 10°S (4. 8 Sv) and at 5°S (4. 7 Sv) west of about 31°30'W enters the Guiana Basin, mainly through the southern half of the Equatorial Channel at 35°W (1. 5-1. 8 Sv). The other part recirculates and some of it flows through the Romanche Fracture Zone into the eastern Atlantic. In the Guiana Basin, west of 40°W, the sloping topography and the strong, eastward flowing deep western boundary current might prevent the AABW from flowing west: thus it has to turn north at the eastern slope of the Ceara Rise (2. 2 Sv). At 44°W, north of the Ceara Rise, AABW flows west in the interior of the basin in a main core near 7°15'N (1. 9 Sv). A net return flow of about 0. 5 Sv was found north of 8°43'N. A large fraction of the AABW (1. 1 Sv) enters the eastern Atlantic through the Vema Fracture Zone, leaving only 0. 3 Sv of AABW for the western Atlantic basins.
Industry:Earth science
The eastern part of a cyclonic gyre centered around 13° S and 4° E that is driven by the South Equatorial Countercurrent in the Atlantic Ocean. This subsurface circulation gyre extends from just below the surface to around 300 m depth with velocities of about 0. 5 m/s in the section nearest the African coast. The confluence between this southward flowing current and the northward flowing Benguela Current near 16° S off the African coast is called the Angola-Benguela Front.
Industry:Earth science
A German term for a quantity equivalent to the eddy viscosity coefficient.
Industry:Earth science
An NSF global change program. The goals of ARCS are to understand the chemical, physical, biological and social processes of the arctic system that interacts with the total earth system and thus contributes to or is influenced by global change in order to advance the scientific basis for predicting environmental change on a decade to centuries time scale.
Industry:Earth science
