shear wave
292
large, wave-like or eddying motions. In vertical shear, instability is counteracted by a stable density stratification, and the criterion for the occurrence
of shear instability is attained when the value of the gradient Richardson number falls below a critical value (about 1, but depending on additional circumstances). This type of instability is also known as Kelvin-Helmholtz instability. It can result in regular disturbances in the form of overturning internal
waves or Kelvin-Helmholtz billows. The small-scale turbulence produced by this
process ultimately causes an intermediate mixed layer.
shear wave -tS-wave.
shelf break -tshelf sea.
shelfsea shallow (usually less than 200 m deep) sea area bordering a continent
that geologically can be considered an extension of the continent (continental shelf). A more or less steep slope (shelf break) forms the transition to the
deep ocean. Shelf seas form less than 8 % of the total ocean area.
shellfish term used in fisheries science denoting commercial marine invertebrate species, mostly Bivalvia, Gastropoda, shrimps, and prawns.
shellfish farming culture of shellfish in ponds (shrimps), in shallow basins (oysters) or in natural shallow sea areas (mussels). The idea of shellfish farming
is generally to remove as many other organisms as possible from the culture
substrate (which can be either natural or artificial), and stock it with settling
brood collected in nature. The productivity of such artifical populations of
shellfish may be high due to optimal food conditions, low mortality, and
harvesting directly after the rapid juvenile growth. -taquaculture and -tsea
farming.
ship waves a moving ship generates short surface gravity waves. If the ship (or submarine) passes through stratified water it may also generate internal waves.
shipworm wood-boring member of the Bivalvia which does great damage to
wooden wharves, ships, etc. Example: Teredo.
shoal (1) shallow area in the sea; (2) aggregation of fish. -tschooling.
shoaling of waves -twave approach.
short wave gravity wave with a wavelength that is less than four times water depth.
The orbital motion is not influenced by the bottom. Their propagation, only
depending on wave number, shows dispersion. They are sometimes called deep
water waves.
292
large, wave-like or eddying motions. In vertical shear, instability is counteracted by a stable density stratification, and the criterion for the occurrence
of shear instability is attained when the value of the gradient Richardson number falls below a critical value (about 1, but depending on additional circumstances). This type of instability is also known as Kelvin-Helmholtz instability. It can result in regular disturbances in the form of overturning internal
waves or Kelvin-Helmholtz billows. The small-scale turbulence produced by this
process ultimately causes an intermediate mixed layer.
shear wave -tS-wave.
shelf break -tshelf sea.
shelfsea shallow (usually less than 200 m deep) sea area bordering a continent
that geologically can be considered an extension of the continent (continental shelf). A more or less steep slope (shelf break) forms the transition to the
deep ocean. Shelf seas form less than 8 % of the total ocean area.
shellfish term used in fisheries science denoting commercial marine invertebrate species, mostly Bivalvia, Gastropoda, shrimps, and prawns.
shellfish farming culture of shellfish in ponds (shrimps), in shallow basins (oysters) or in natural shallow sea areas (mussels). The idea of shellfish farming
is generally to remove as many other organisms as possible from the culture
substrate (which can be either natural or artificial), and stock it with settling
brood collected in nature. The productivity of such artifical populations of
shellfish may be high due to optimal food conditions, low mortality, and
harvesting directly after the rapid juvenile growth. -taquaculture and -tsea
farming.
ship waves a moving ship generates short surface gravity waves. If the ship (or submarine) passes through stratified water it may also generate internal waves.
shipworm wood-boring member of the Bivalvia which does great damage to
wooden wharves, ships, etc. Example: Teredo.
shoal (1) shallow area in the sea; (2) aggregation of fish. -tschooling.
shoaling of waves -twave approach.
short wave gravity wave with a wavelength that is less than four times water depth.
The orbital motion is not influenced by the bottom. Their propagation, only
depending on wave number, shows dispersion. They are sometimes called deep
water waves.