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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 joint oceanographic research endeavor of Indonesia and the United States whose primary goal is to study the circulation and water mass stratification within the Indonesian Seas, especially to determine sources, pathways, and mixing histories of the throughflow water masses for the monsoon extremes. Arlindo is an acronym for Arus Lintas Indonesia, meaning ``throughflow'' in the Bahasa Indonesian language.
The first stage of the project, Arlindo Mixing, consisted of a suite of CTD measurements extending to the seafloor or 3000 dbar, tracer chemistry, and biological productivity stations obtained from the Indonesian research vessel Baruna Jaya I during the southeast monsoon of 1993 (Aug. 6 to Sept. 12) and northwest monsoon of 1994 (Jan. 25 to Mar. 3). The results have been summarized as:
The primary interocean throughflow path in the upper thermocline is that of North Pacific thermocline water flowing through the Makassar Strait into the Flores and southern Banda Seas before curling southward into the Timor Sea and Indian Ocean. This path tracks the mostxi persistent course of water masses core layer indicators along a potential throughflow pathway. Even in the southern Banda Sea the North Pacific core layer indicators are evident, albeit very attenuated; they are not observed in the northern Banda Sea, which attests to the Makassar/Flores origin. The sill at the southern end of Makassar Strait is about 550 m deep. No signs of deep water upwelling lifting over the sill is evident. An attenuated, fragmented thermocline salinity and CFC maximum layer in Makassar Strait during the NWM relative to the SEM, suggests that the throughflow slackens in that season, allowing accumulative effects of local mixing.
East of Sulawesi there is little evidence of North Pacific water mass throughflow into the Banda Sea. The North Pacific thermocline water entering the northwest corner of the Maluku Sea, exits back to the north in the northeast corner of the Maluku Sea. The presence of relatively salty water of South Pacific origin is observed in the 10?-14?C interval in the Seram Sea. This water enters the Seram Sea directly from the South Pacific via the New Guinea Coastal Current and Halmahera Sea (sill depth near 500 m). Below the thermocline the main source of the throughflow is South Pacific water masses, though they are derived from a more indirect route, via the North Pacific's Mindanao Current, entering the Indonesian Seas at the Maluku Sea. It is this water that spills over the 1940 m deep Lifamatola Sill into the depths of the Banda Sea.
The second stage was called Arlindo Circulation, whose goal was to resolve the throughflow transport and velocity field across the central passages of the Indonesian Seas. It took place from Nov. 20-Dec. 15, 1996 and Feb. 17-Mar. 7, 1988. The third stage is called Arlindo Monitoring and is intended to provide a long term data set of the throughflow to enable study at timescales of ENSO events. It is scheduled from 1998 to 2007.
Industry:Earth science
A French research program to observe and model the movement of the Mediterranean Water (MW) in the eastern North Atlantic Ocean in the interior and along the eastern boundary. It is a joint civilian and military exercise taking place between 40 and 50° N with most of the work to be done east of 14° E up to the 200 meter isobath, although some float work will take place out to 25° W to link with the proposed U. S. RAFOS deployments in this region. The plans call for the release of 60 RAFOS and 40 MARVOR floats. Also deployed will be 7 acoustic sources for tomographic work, 40 drifting buoys drogued at 150 meters mostly on the continental slopes of the Iberian Peninsula, 6 current meter moorings (with a total of 27 current meters) on and near the continental slopes of the Iberian Peninsula for 3 years, and a bottom mounted ADCP to be moored for several 3 month periods. This program is scheduled to last until 1999 and is a companion program to EUROFLOAT.
Industry:Earth science
One of three major basins in the Southern Ocean. It extends from its eastern boundary with the Pacific-Antarctic Basin at the longitude of Tasmania (at about 145° E) to the Kerguelan Plateau (at about 75° E). The South-East Indian Ridge separates it from the Indian Ocean at depths greater than 4000 m except for a gap in the Ridge at 117° E.
Industry:Earth science
The difference between the observed oxygen content and the saturation oxygen content of a sample of sea water. This is a method of estimating the amount of dissolved oxygen utilized by organisms via respiration, although it is called "apparent" for a reason. Surface waters may more than likely carry more than the saturation amount of oxygen due to the nonlinearity in the solubility of oxygen with temperature. The effects of this nonlinearity are small, though, and the AOU is usually quite close to TOU, the True Oxygen Utilization.
Industry:Earth science
An experiment taking place from 1993-1995 whose overall objective was to observe directly the spreading pathways by which Mediterranean Water enters the North Atlantic, including the direct observation of Mediterranean eddies, i.e. meddies. The measurements included repeated high resolution XBT section and RAFOS float deployments across the Mediterranean Undercurrent south of Portugal near 8. 5°W.
A total of 49 floats were deployed at the rate of about two floats per week on 23 cruises of the Portuguese vessel Kialoa II and one cruise of the R/V Endeavor. The floats were ballasted for 1100 or 1200 decibars to seed the lower salinity core of the Undercurrent. The objectives of the float study were:
* to identify where meddies form;
* to make the first direct estimate of meddy formation frequency;
* to estimate the fraction of time meddies are being formed; and
* to determine the pathways by which Mediterranean Water which is not trapped in meddies enters the North Atlantic.
Industry:Earth science
A major eastward flowing current that circles the globe in the Southern Ocean. It is principally driven by surface wind stress, although there is a significant thermohaline component that is not yet well understood. In the way of vorticity dynamics a simple Sverdrup balance with dissipative mechanisms of form drag by bottom topography and lateral dissipation in western boundary layers has been found consistent with the data. The present best estimates of its transport through Drake Passage give a net mean transport of 125 Sv (with a standard deviation of 10 Sv) above 2500 m.
The transport of the ACC is concentrated in two current cores separated by a transition zone with surface water characteristics intermediate between those found to the south in the Antarctic Zone and to the north in the Subantarctic Zone, with the transition zone being known as the Polar Frontal Zone. The maximum geostrophic surface speeds in these cores have been calculated as 25-45 cm s<sup>-1</sup> in Drake Passage.
There is also considerable mesoscale variability in the ACC region due to instabilities causing both cold and warm core rings to be shed. These eddies have been found to have spatial scales varying from 30 to 100 km, surface velocities typically 30 cm s<sup>-1</sup> or greater, and are vertically coherent from surface to bottom. The regions of highest variability have been found to be correlated with prominent topographic features on the sea floor.
The ACC is a region of complicated and large meridional heat flux, with a mean ocean heat loss to the south estimated at about 0. 45 petawatts due to ocean-atmosphere heat exchange and equatorward Ekman transport. This is thought to be balanced by the import of heat via eddy processes and deep boundary currents, although the proportions are known only vaguely as yet.
Industry:Earth science
The product of mass times the perpendicular distance from the axis of rotation times the rotation velocity. The angular momentum about the Earth's axis of rotation can be expressed as the sum of the angular momentum of the solid Earth's rotation plus the angular momentum of zonal air motion relative to the surface of the Earth. Were this quantity to be absolutely conserved, a parcel of air with the angular momentum of the Earth's surface at the Equator would have a westerly zonal wind speed of 134 m/s at 30° latitude.
Industry:Earth science
One of four principal types of estuaries as distinguished by prevailing flow conditions. This is a type in which there is a relatively stationary interface between an underlying stable salt wedge of sea water and an overlying strong flow of fresh river water.
Industry:Earth science
A water mass found in the arctic domain in the North Atlantic Ocean. The ASW is the summer surface water mass above the seasonal thermocline and has temperatures greater than 0° C for the salinity range 34. 4 to 34. 7 and greater than 2° C for the range 34. 7 to 34. 9.
Industry:Earth science
A marginal sea of Antarctica centered at about 112° W and 73° S. It sits between the Bellingshausen Sea to the east and the Ross Sea to the west, with the Antarctic Circle serving as the northern boundary.
Industry:Earth science
