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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 northwestward flowing current in the central Yellow Sea that brings warm water from the Kuroshio Current with velocities that are a maximum of about 0.2 m/s at the surface and decrease rapidly with depth. This keeps the central waters several degrees warmer than those near the coast. The is also known as the Yellow Sea Warm Current.
Industry:Earth science
A method wherein a specialized radar called a scatterometer is used to measure the near-surface wind speed and direction. The technique is indirect, i.e. the instrument tranasmits microwave pulses and receives backscattered power from the ocean surface. Changes in wind velocity cause changes in ocean surface roughness, modifying the radar cross-section of the ocean and the magnitude of backscattered power. This backscattered power is measured by scatterometers to obtain an estimate of the normalized radar cross-section of the sea surface. The cross-section varies with both wind speed and direction when measured at moderate incidence angles, allowing the development of a transfer function called a geophysical model function relating the former to the latter. Multiple, collocated, nearly simultaneous cross-section measurements acquired from several directions can be used to simultaneously solve for wind speed and direction.
Industry:Earth science
A multi-agency operational center which includes personnel from two NOAA departments, the NESDIS and the NWS. Its mission is to provide worldwide, operational sea ice analyses and forecasts for the armed forced of the U.S. and allied nations as well as for other U.S. government agencies and the civil sector. These products are provided for the Arctic, Antarctic, Great Lakes and Chesapeake Bay.
Industry:Earth science
A type of water created by property modification in the vicinity of ocean fronts, especially during winter. Convection creates a deep surface layer containing water of nearly uniform temperature and salinity in regions that usually feature strong horizontal and vertical gradients. A Mode Water core is defined by the existence of minima in vertical gradients. Commonly used properties are temperature and potential density anomaly, with the minimum gradient layer then being known as, respectively, a thermostad or pycnostad.
The mode water sinks along isopycnal surfaces, retaining its properties since they can only be changed by mixing with the surrounding water. Since deep mixing processes are much weaker at depth than near the surface, mode waters tend to retain their characteristics for great distances as they move around the ocean basins. Their persistent properties make them excellent tracers for climate change studies since they retain a record of surface conditions at the time of their formation.
There are two general varities of mode water: subtropical mode water and subpolar mode water. Types of subtropical mode waters include:
* Eighteen Degree Water
* North Pacific Subtropical Mode Water
* North Atlantic Subtropical Mode Water
* Madeira Mode Water
Types of Subpolar Mode Waters include:
* Subantarctic Mode Water
** Antarctic Intermediate Water
** Southeast Indian SAMW
* North Atlantic Subpolar Mode Water.
Industry:Earth science
An instrument used to determine ocean depth by measuring the time needed for a sound wave to travel from the ship to the ocean floor and return. The first reliable acoustical sounding machine was built by A. Behm in 1919, who called it an echo sounder. An echo sounder consists of three main components: the sound transmitter, the sound receiver, and a device to measure time.
Industry:Earth science
In physical oceanography, the total meridional heat transport due to mesoscale eddies. This has also been used to refer to the correlation of time-dependent fluctuations of velocity and temperature across a section, which is not indicative of the total heat transport due to eddies. Eddies can also induce a thermally driven, overturning cell in subtropical gyres that is analogous to the Ferrel cell in the atmosphere. This cell contributes to the time-averaged transport and its contribution may be as large as that of the time-dependent correlations. This is also called eddy conduction or eddy heat conduction.
Industry:Earth science
The time it takes a system to reduce an imposed displacement to a factor of 1/e of the displaced value. This is a common way of expressing the equilibration time of a system. The e-folding concept is often applied to distances as well as times.
Industry:Earth science
(1897-1975)One of the founders of modern meteorology, Bjerknes entered and revolutionized the field at the age of 20 with his discovery of the structure of extratropical cyclones. His father was the physicist and geophysicist Vilhelm Bjerknes.
Industry:Earth science
The portion of the nearshore zone where waves arriving from offshore become unstable and break.
Industry:Earth science
In studying air-sea interactions, it is difficult to obtain direct measurements of the surface fluxes, and those that are available are extremely limited in geographic scope. Therefore, extensive, global-scale estimates must be obtained via parameterizations of the surface fluxes that permit the use of more easily obtained quantities. The basic premise of the concept of bulk parameterizations is to relate the surface layer fluxes to logarithmic profiles of the mean quantities. The fluxes can then be determined from the mean wind, temperature and humidity at a single height by introducing bulk transfer coefficients of heat, moisture and momentum. This method is also used to quantify gas exchange processes.
Industry:Earth science
