Use the “Quick Search” box to locate your required term and/or definition. The following “Search conditions” can be used to refine your search: “Contains”, “Begins with”, “Ends with”, “Equals”, “Does not contain” or “Does not equal.”
Eng ID Term Definition
4621
seaward
(adj. and adv.). Away from the LAND; toward the SEA.
4622
sea water
The water of the SEAS, distinguished from fresh water by its appreci­able SALINITY. The degree of the SALINITY greatly affects the water's p... more
The water of the SEAS, distinguished from fresh water by its appreci­able SALINITY. The degree of the SALINITY greatly affects the water's physical charac­teristics.
4623
sea water: colour of
The apparent colour of the sur­face layers of the SEA caused by the REFLECTION of certain components of the visible light spectrum cou­pled ... more
The apparent colour of the sur­face layers of the SEA caused by the REFLECTION of certain components of the visible light spectrum cou­pled with the effects of dissolved material, con­centra­tion of PLANKTON, DETRITUS, or other matter. Colour of oceanic water varies from deep blue to yellow and is expressed by number values which are a variati­on of the FOREL SCALE. Plankton concentrations may cause a tempo­rary appearance of red, white, green, or other colours. Also called water colour. See also DISCOLOURED WATER.
4624
seaway
A moderately rough SEA. Used chiefly in the expression 'in a seaway'. HEADWAY of a vessel. The SEA as a route of travel from one place to an... more
A moderately rough SEA. Used chiefly in the expression 'in a seaway'. HEADWAY of a vessel. The SEA as a route of travel from one place to ano­ther; a shipping LANE.
4625
seaweed
Any macroscopic marine ALGA or SEAGRASS.
4626
Secchi disc
A white, black, or varicoloured disc, 30 centimetres in diameter, used to measure water trans­parency (clarity). The disc is lowered in the ... more
A white, black, or varicoloured disc, 30 centimetres in diameter, used to measure water trans­parency (clarity). The disc is lowered in the water and the DEPTH (in METRES) at which it disappears from sight is averaged with the DEPTH at which it reappe­ars. This average value is used to represent sea water transpar­ency.
4627
second
The unit of TIME in the SI system. A sixtieth part of a MINUTE, an angle or an arc.
4628
secondary port
See STATION: SUBORDINATE.
4629
secondary radar
See RADAR: PRIMARY.
4630
secondary station
See STATION: SUPPLEMENTARY.
4631
secondary tide(s)
See TIDE.
4632
secondary tide station
See STATION: TIDE.
4633
second nodal point
See NODAL POINT.
4634
second order triangulation
See TRIANGULATION CLASSI­FICA­TION.
4635
section
Process of locating and coordinating a point from at least two existing control stations by observing horizontal directions from the control... more
Process of locating and coordinating a point from at least two existing control stations by observing horizontal directions from the control stations to the point. Also called intersection.
4636
sector scan sonar
A horizontal aperture SONAR used to detect obstructions ahead of the vessel by mechanical or electronic scanning in the horizontal plane.
4637
secular change
An increase or decrease of intensity and/or change of direction of the total MAGNETIC FIELD over a period of many years.
4638
sediment
Particulate organic and inorganic matter which accumulates in a loose unconsolidated form. It may be chemically precipitated from solution, ... more
Particulate organic and inorganic matter which accumulates in a loose unconsolidated form. It may be chemically precipitated from solution, secreted by organisms, or transported by air, ICE, WIND, or water and deposited.
4639
sediment(s): bottom
In general all sedimentary materi­al regardless of origin found on or in the submarine BOTTOM, including ballast or other material dumped in... more
In general all sedimentary materi­al regardless of origin found on or in the submarine BOTTOM, including ballast or other material dumped into the SEA by man. More specifically it is limited to unconsolidated mineral and organic material forming the sea bottom, not including CORAL REEFS or BEDROCKS.
4640
sediment survey
A survey to determine the nature and distribution of types of sea bottom SEDIMENTS.