- 産業: Education
- Number of terms: 34386
- Number of blossaries: 0
- Company Profile:
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 ...
In signal processing this refers to a continuous physical variable which bears a direct relationship to another variable so that one is proportional to the other. An example would be the mercury level in a thermometer and its relation to the temperature, both of which vary continuously on the macroscopic level. Contrast with digital.
Industry:Earth science
A satellite-borne instrument designed to measure land and ocean surface temperatures. The ATSR is a passive two-channel radiometer that scans the near-infrared and middle-infrared bands with a spatial resolution of 1 km x 1 km and a swath width of 500 km. It views the Earth from an orbit of about 800 km and can measure ocean temperature to within 0. 3° C. The ATSR can be used to detect exceptional local incidents, large scale changes, and general trends in the Earth's climate.
Industry:Earth science
A name given to the region in the Southern Ocean between the Polar Front to the north and the Southern ACC Front to the south. The AZ is one of four distinct surface water mass regimes in the Southern Ocean, the others being the Continental Zone (CZ) to the south and the Polar Frontal Zone (PFZ) and Subantarctic Zone (SAZ) to the north.
Industry:Earth science
A property of sea water operationally defined as the excess positive charge to be balanced by CO<sup>3</sup> and HCO<sup>3</sup> ions. The carbonate ion content of any unit of sea water is equal to its alkalinity (i.e. excess positive charge) minus its total dissolved carbon content.
Industry:Earth science
The ALT was the first spaceborne dual-frequency altimeter and is the primary instrument for the mission. Measurements are made at two frequencies (5. 3 and 13. 6 GHz) and combined to minimize the errors caused by the presence of ionospheric free electrons, the total content of which is obtained as a by-product of the measurement. This instrument was based on previous Seasat and Geosat altimeters with several improvements including the 5. 3 GHz channel for the ionospheric measurement, more precise height measurement, and a longer lifetime.
Industry:Earth science
An investigation whose primary goal was to identify continental shelf waves (CSW). It was carried out off the coast of New South Wales (eastern Australia) between Cape Howe and Newcastle from September 1983 to March 1984. The experiment included an array of current meters with three main lines with five moorings each, repeated CTD and XBT surveys, meteorological measurements from moored buoys and coastal stations, sea level measurements at coastal tide gauges, and bottom pressure measurements at a few sites. Each of the three mooring lines was arranged perpendicular to the local coastline, were nominally identical, and consisted of 15 Aanderaa current meters on 5 moorings.
A free wave analysis of the data gathered demonstrated that waves passed through the experimental array and exhibited dispersion characteristics strongly indicative of coastal trapped waves. The measured pattern speed was between those predicted for free and forced waves. There was some predictive skill using a trapped wave model. Although the model predictions only accounted for a maximum of 40% of the observed variance, the best statistical predictor could only account for 50%. This led to the conclusion that not all of the energy in the weather forcing band was described by coastal trapped waves.
Industry:Earth science
A regional sea, centered at approximately 65° E and 15° N, that is bounded by Pakistan and Iran to the north, Oman, Yemen and the Somali Republic to the west, India to the east, and the greater Indian Ocean to the south. The southern boundary, from an oceanographic point of view, runs from Goa on the Indian coast along the west side of the Laccadive Islands to the equator, and thence slightly to the south to near Mombasa on the Kenyan coast. It covers an area of about 7,456,000 km<sup>2</sup>.
The flow pattern in the Arabian Sea is seasonal, changing with the monsoon winds. In the northeast monsoon season (from November until March) the winds are light and the surface circulation is dominated by a weak westward, counter-monsoon flow (as an extension of the North Equatorial Current) with velocities usually under 0. 2 m/s. This pattern starts in November with water supplied by the East Indian Winter Jet flowing around the southern tip of Indian and heading northwestward along the western Indian shelf.
Westward flow dominates in the southern parts until late April with the north gradually shifting into a weak anticyclonic pattern. With the advent of the southwest monsoon in April, the Somali Current and its northward extension, the East Arabian Current, both develop into strong, northeastward flowing currents by mid-May. The anticyclonic pattern in the eastern Arabian Sea is simultaneously being gradually replaced by a moderate eastward flow composed of extensions of the Somali Current and the Southwest Monsoon Current. This pattern lasts for 4-5 months, peaking in June and July at about 0. 3 m/s and weakening rapidly in October as the eastward flow around southern India once again pushes northwestward.
From May to September there is strong upwelling in the East Arabian Current along Oman, accompanied by a 5° C or more lowering of coastal temperatures due to the cold upwelling water. This upwelling isn't as conducive to primary production as elsewhere due to the rapidly moving current removing much of the upwelled additional biomass before it can be utilized.
Industry:Earth science
A large gulf or lagoon, centered at about 46° N and 37° E, connected to the Black Sea by the narrow and shallow (around 5 m sill depth) Kerch Strait. The Sea of Azov covers around 38,000 sq. km which comprises 9% of the area of the Black Sea system but only 0. 5% of the volume.
Industry:Earth science
A frontal zone that runs meridionally between about 5 and 8° E in the Greenland Sea. It separates warm, salty, northward-flowing Norwegian Atlantic Water (NwAtW) in the Norwegian Atlantic Current and the West Spitsbergen Current to the east from the cooler and fresher Arctic Surface Water (ASW) in the Greenland Sea gyre to the west.
The AFZ consists of two semipermanent frontal interfaces with warm, saline Norwegian Atlantic Water to the east and Arctic Water from the Greenland Sea gyre to the west. These two interfaces bound a band of shallow cyclonic cold eddies and anticyclonic warm eddies with horizontal scales on the order of 40-50 km, consistent with the local Rossby radius. Drifter trajectories show a mean surface velocity across the AFZ to the north, and the mean northward geostrophic transport (relative to 1000 dbar) connected with the zonal density gradient in the AFZ is about 3. 8 Sv. The accompanying transports of heat and fresh water across the AFZ are thought to be of great importance for the control of deep convection processes in the Greenland Sea gyre.
Industry:Earth science
A center of action centered over the Aleutian Islands between the east coast of the Siberian Kamchatka Peninsula and the Gulf of Alaska at about 50° N. It is prominent in the winter and disappears in summer, with the average central pressure below 1000 mb in January.
Industry:Earth science
