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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 JGOFS project to obtain and study long-term time-series of biogeochemical cycles in the Sargasso Sea near Bermuda.
Industry:Earth science
A regional sea located in the northwest corner of the South Pacific Ocean. The Bismarck Sea is bounded to the southwest by New Guinea and to the north, east, and south by the Bismarck Archipelago. Its area and volume are about 40,000 km<sup>2</sup> and 60,000 km<sup>3</sup>, respectively.
Industry:Earth science
A narrow ocean passage separating the North American and Asian continents. The transport of water through this passage, estimated at about 0. 6 Sv of northward flowing low salinity water largely supplied by the Anadyr Current, contributes little to the global budgets of any ocean properties. Its principal role in large-scale circulation is apparently its contribution to the stratification of the Arctic Ocean.
Industry:Earth science
A GEWEX project to study coupled hydrological processes between complicated terrain, sea and ice and the atmospheric circulation to determine the energy and water budgets of the Baltic Sea and related river basins. The scientific objectives are:
* to explore and model the various mechanisms determining the space and time variability of energy and water budgets of the BALTEX area and its interactions with surrounding regions;
* to relate these mechanisms to the large-scale circulation systems in the atmosphere and oceans; and
* to develop transportable methodologies to contribute to research in other regions.
Industry:Earth science
A large sea located between the Canadian Archipelago and the Labrador Sea. It is about 1000 km and 400 km. Most of Baffin Bay is deeper than 1500 m, but deep water exchange with the Labrador Sea is restricted by a sill in Davis Strait with a depth of 670 m. A mobile ice cover forms during winter and moves southward under the prevailing winds. Icebergs calved from glaicers in southern and western Greenland drift across the bay and southward in the Baffin Current to southern latitudes. A significant oceanographic feature of Baffin Bay is the North Water, a partially open water area in the northern part where complete ice cover would be expected under prevailing climatological conditions.
The principal currents are a relatively warm northwards flowing current along the Greenland coast, and the cold southwards flowing Baffin Current. This cyclonic circulation is driven by surface inflows of low salinity Arctic water through the Canadian Archipelago in the north and by means of the West Greenland Current in the south. Current meter data from northern Baffin Bay show strong surface Arctic outflows to a depth of about 500 m, directed to the south and generally following the bathymetry. There is a strong annual cycle in the mean currents, with the currents stronger in summer and weaker in winter. This variability is probably driven by seasonal changes in buoyancy forcing, which enhances the coastal currents on the wide shelves. Tidal currents up to 0. 4 m s<sup>-1>/sup> have been observed on the shelves and along the shelf slopes, and consist mainly of semidiurnal components, with a considerable diurnal component in some areas.
The surface layer, defined as the layer extending to the maximum depth influenced by wind stress, is a few tens of meters thick. The surface layer water has a density of 1026 kg/m<sup>3</sup> or less, with the deeper water weighing in at 1027 kg/m sup>3</sup>. Their salinities are 32. 5 and 34. 0, respectively. In the eastern part of the bay there is a layer between about 200 and 800 m characterized by relatively warm and saline water. This is considered the result of inflow of Atlantic water through the Davis Strait. Substantial tidal currents have been measured in the eastern part of the bay, e.g. up to about 20 cm/s at locations where the water depth is 500 m.
Industry:Earth science
A marginal sea located on the northern rim of the Pacific Ocean centered at approximately 58° N and 160° W. It is surrounded by Alaska to the east, Siberia to the west and northwest, and the Aleutian Island arc to the south. It has an area of about 2,300,000 km<sup>2</sup> and a volume of about 3,700,000 km<sup>3</sup>. The bathymetry is about equally divided between a vast shelf to the northeast that is at most 200 m deep and the Aleutian Basin where depths range from 3800-3900 m over most of the region. The Shirshov Ridge (along 171° E between 500-1000 m depth) and the shallower Bowers Ridge (along 180° E then turning west along 55° N) effectively divide the Basin into three parts. It is connected to the Arctic Mediterranean Sea via the Bering Strait and to the Pacific via several sills between the various Aleutian Islands, although the main connection is thought to be between 168° E and 172° W where the sill depth is about 1590 m.
The main circulation features include a large part of the westward flowing Alaskan Stream entering the Bering Sea through the passage centered at 170° W, turning east, and driving a cyclonic (counterclockwise) gyre in the Aleutian Basin. This largely barotropic current sees the two main ridges as obstacles which sets up a system of two eddies, one on each side of the Shirshov Ridge. Eddies have been observed separating from the eastern limb (often called the Bering Slope Current) of the Bering Sea gyre, the larger of the two systems. There is a countercurrent further up the Bering Slope whose dynamics are those of an eastern boundary current in a subpolar gyre. A series of currents and related fronts largely driven by Alaska Stream inflow through a shallower passage at 175° W flow north-northwestward on the broad shelf region.
The main circulation feature of the northern Bering Sea is the Anadyr Current, a largely seasonally invariant current flowing northeastward and supplying most of the Bering Strait throughflow. This throughflow, driven by sea level differences across the strait, varies from about 0. 1 m/s in the summer to 0. 5 m/s in the winter, with flow through the Shpanberg Strait seasonally shifting from northward to southward to compensate for the differences. The shelf flows also make some mostly unknown contribution to this throughflow. The western limb of the smaller gyre to the west of the Shirshov Ridge contributes to and becomes part of the southwestward flowing Kamchatka Current.
The local water masses are derived from Pacific Ocean water masses transported in to the area and modified by processes on the shelf. This results in a temperature minimum at or below 100 m, low surface salinities rapidly rising to about 300 m, and overall low oxygen concentrations. The water overlying the temperature minimum is surface water imported from the Alaska Stream, and the water below that is Pacific Deep Water.
Industry:Earth science
A current that flows from southeast to northwest across the Aleutian Basin of the Bering Sea, parallel to the continental slope of the eastern Bering Sea shelf.
Industry:Earth science
One of three major ecological groups into which marine organisms are divided, the other two being the nekton and the plankton. The benthos are organisms and communities found on or near the seabed. This includes those animals (zoobenthos) and plants (phytobenthos) living on (epifauna) or in (endofauna) marine substrata as well as those that swim in close proximity to the bottom without ever really leaving it. In terms of size, this is generally divided into three categories: meiobenthos, the organisms that pass through a 0. 5 mm sieve; macrobenthos, those that are caught by grabs or dredges but retained on the 0. 5 m sieve; and epibenthos, those organisms than live on rather than in the seabed. Those in the latter category are usually larger.
Benthic life is subject to vertical zonation depending chiefly on light, moisture and pressure. This has led to the division of benthonic animals into two systems and seven zones. Proceeding from shallow to deep water, the first system is the phytal or littoral system, composed of the supralittoral, mediolittoral, infralittoral and circalittoral zones. The second system, the aphytal or deep system, is composed of the bathyal, abyssal and hadal zones.
Industry:Earth science
A thermometer with an insulated container around the bulb. It is used to measure ocean temperatures by lowering it on a line, allowing it to equilibrate with the temperature of the surface water, withdrawing it along with the water surrounding it, and reading the temperature. The water serves both as insulation for the thermometer (after withdrawal) and as a sample for a salinity determination.
Industry:Earth science
