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residual current
marine. Like all snakes they are strictly carnivorous and they use a venom to
paralyze their prey. This venom is very toxic to man, but luckily they are mostly not aggressive. Marine turtles are tortoises adapted to life in the sea by the
possession of limbs that are flat flippers. Only seven species are known. Eggs
are deposited in holes dug in sandy beaches. The breeding areas on land are
often widely separated from the feeding area. Some Green turtles feed on seagrass meadows off the Brazilian coast and migrate 2000 km to Ascension
Island for egg-laying as found by tagging. They must have a remarkable navigation capacity to return to this small island where they were born. Turtles are
sometimes observed outside their normal distribution area. Between 1950
and 1966,61 (probably five species) were observed in UK waters. During hot
summers the area in which they can survive may be enlarged: most specimens
in UK and Norwegian waters are sighted in June to November. There are also
records from the Dutch coast. Famous fossil marine reptiles (Ichthyosaurus,
Mosasaurus) lived in the Mesozoic when reptiles were the dominant vertebrates.
research vessels especially designed or converted vessels for carrying out marine
research for physical, chemical, biological, and geological oceanographic
studies. Basic instruments on board are deep-sea winches, sampling equipment, and laboratories for immediate investigation of the samples or preparation for storage. A modern development of marine research vessels is the
application of multipurpose containerization for laboratories, winches,
workshops, and supply units.
residence time (1) factor that characterizes the general behavior of elements in the
oceans. Residence time (T) is defined by the ratio of the total amount of material present in solution and suspension (A) in a basin (or all oceans), and the
amount introduced or precipitated (dA/dt). Conservative elements (Na, Mg,
Ca, K and Sr) have a very long T, for instance over 10 7 years for all oceans
together, while nonconservative elements have much smaller T values, such
as: AI (100 y), Pb (2000 y) and Mn (140 y). High T values correlate with high
solubility, while low Tvalues reflect tendencies to precipitation; (2) term used
in hydrography to denote the average time a water molecule stays in a certain
sea area (e.g., in an estuary or in a shelf area, where the water is continuously
replaced by river flow or exchange with the open sea). ~time scales.
residual current in a sea area where the tide dominates, the effect of other
dynamic factors causing current (wind, pressure gradients) only becomes
manifest when the tidal currents are eliminated from the observations by
mathematical filtering techniques. The current that remains after this elimination is called the residual current. It appears that the tides themselves,
due to nonlinear dynamic behavior, may also give rise to constant, permanent currents that are part of the residual current thus defined. This tidal
contribution is known as the tidal residual.
residual current
marine. Like all snakes they are strictly carnivorous and they use a venom to
paralyze their prey. This venom is very toxic to man, but luckily they are mostly not aggressive. Marine turtles are tortoises adapted to life in the sea by the
possession of limbs that are flat flippers. Only seven species are known. Eggs
are deposited in holes dug in sandy beaches. The breeding areas on land are
often widely separated from the feeding area. Some Green turtles feed on seagrass meadows off the Brazilian coast and migrate 2000 km to Ascension
Island for egg-laying as found by tagging. They must have a remarkable navigation capacity to return to this small island where they were born. Turtles are
sometimes observed outside their normal distribution area. Between 1950
and 1966,61 (probably five species) were observed in UK waters. During hot
summers the area in which they can survive may be enlarged: most specimens
in UK and Norwegian waters are sighted in June to November. There are also
records from the Dutch coast. Famous fossil marine reptiles (Ichthyosaurus,
Mosasaurus) lived in the Mesozoic when reptiles were the dominant vertebrates.
research vessels especially designed or converted vessels for carrying out marine
research for physical, chemical, biological, and geological oceanographic
studies. Basic instruments on board are deep-sea winches, sampling equipment, and laboratories for immediate investigation of the samples or preparation for storage. A modern development of marine research vessels is the
application of multipurpose containerization for laboratories, winches,
workshops, and supply units.
residence time (1) factor that characterizes the general behavior of elements in the
oceans. Residence time (T) is defined by the ratio of the total amount of material present in solution and suspension (A) in a basin (or all oceans), and the
amount introduced or precipitated (dA/dt). Conservative elements (Na, Mg,
Ca, K and Sr) have a very long T, for instance over 10 7 years for all oceans
together, while nonconservative elements have much smaller T values, such
as: AI (100 y), Pb (2000 y) and Mn (140 y). High T values correlate with high
solubility, while low Tvalues reflect tendencies to precipitation; (2) term used
in hydrography to denote the average time a water molecule stays in a certain
sea area (e.g., in an estuary or in a shelf area, where the water is continuously
replaced by river flow or exchange with the open sea). ~time scales.
residual current in a sea area where the tide dominates, the effect of other
dynamic factors causing current (wind, pressure gradients) only becomes
manifest when the tidal currents are eliminated from the observations by
mathematical filtering techniques. The current that remains after this elimination is called the residual current. It appears that the tides themselves,
due to nonlinear dynamic behavior, may also give rise to constant, permanent currents that are part of the residual current thus defined. This tidal
contribution is known as the tidal residual.