STANDING WAVE 



highest for the year during this period. This 

 condition occurs most frequently in regions of 

 the higher latitudes which experience some form 

 of vertical mixing. 



spring range — See mean spring range. 



spring rise — See mean spring rise. 



spring — See spring tides. 



spring sludge — See rotten ice. 



spring tide — (or springs). Tide of increased 

 range which occurs about every two weeks when 

 the moon is new or full (syzygy). (50) {See 

 figure for tide cycle.) 



spur — 1. A subordinate elevation, ridge, or rise 

 projecting outward from a larger feature. (62) 



2. A ridge, usually composed of sand or 

 gravel, which extends into the sea from the shore 

 or from a larger submarine elevation. (68) 



3. See ram. (59) 



squeeze — (or harotrauma). A type of injury 

 occurring in divers, usually during descent, 

 which comes about because of inability to equal- 

 ize pressure between a closed air space, such as 

 the middle ear, and outside water pressure. 



squid — (or decapod mollusk). One of an order 

 (Decapoda) of cephalopods in which the body 

 is cigar shaped or globose and bears ten arms, 

 eight of which are of equal length with suckers 

 along the entire length and two of which are 

 longer with suckers only on a broad terminal 

 portion ; shell, in most, is embedded in the body 

 or absent. Some species (the sea arrows) are 

 among the faster nekton, one species (the giant 

 squid) is the largest known invertebrate and a 

 food of the sperm whale, and others have been 

 suggested as possible sound scattering compo- 

 nents of the deep scattering layer. 



Staballoy slide* — A trade name for a gold-plated 

 glass slide used in the mechanical bathythermo- 

 graph to record the temperature versus depth 

 trace. 



stability — The resistance to overturning or mix- 

 ing in the water column, resulting from the pres- 

 ence of a positive density gradient. 



stabilizing force — The ordinary restoring force 

 in an unstable-type gravimeter. 



stable gravimeter — A gravimeter having a sin- 

 gle weight or a spring such that the sensitivity is 

 proportional to the square of its period. 



stable isotope — 1. An isotope of an element 

 which is not radioactive. 



2. A mixture of isotopic nonradioactive nu- 

 clides of composition different from that occur- 

 ring in nature, as an article of commerce. 



3. In common usage, any stable nuclide (not 

 preferred). 



(41) 



stable polynya — See polynya. 



stable-type gravimeter — A gravimeter which 

 uses a high order of optical and/or mechanical 

 magiiification so that a change in position of a 

 weight or associated property is measured 

 directly. 



stagnant glacier — An inactive glacier. ( 65 ) 



stalked barnacle — (or goose hamacle, gooseneck 

 harnacle). A barnacle whose body is differen- 

 tiated into the body proper, which usually is 

 covered by a two-valved shell, and a stalk at 

 the base, by which the animal is attached to a 

 firm surface. Many are pelagic or deep living, 

 and some are attached to free-floating objects, 

 floating seaweed, hulls of ships, and whales. 



stamuhka — A Russian word for sea ice stranded 

 on a shoal or shallows. 



stand — See stand of tide. 



standard depth — A depth below the sea surface 

 at which water properties should be measured 

 and reported, either directly or by interpolation, 

 according to the proposal by the International 

 Association of Physical Oceanography in 1936. 

 The accepted depths (in meters) are: 0, 10, 20, 

 30, 50, 75, 100, 150, 200, 250, 300, 400, 500, 600, 

 800, 1000, 1200, 1500, 2000, 2500, 3000, 4000, 

 5000, 6000,- 7000, 8000, 9000, 10000, to which 

 NODC has added 125, 700, 900, 1100, 1300, 1400, 

 and 1750. 



standard deviation — (symbol g). The positive 

 square root of the variance ct^. This is a meas- 

 ure of the scatter or spread in a series of obser- 

 vations. (5) 



standard displacement — The surface displace- 

 ment of a submarine, exclusive of the water in 

 nonwatertight st.ruct.ure, when fully manned, en- 

 gined, and equipped for sea duty, including all 

 armament and ammunition, equipment, provi- 

 sions for crews, miscellaneous stores, and imple- 

 ments of every description that are intended to 

 be carried in war but excluding fuel, lubricating 

 oil, fresh water, or ballast water of any kind. 

 This definition was established by the 1930 Lon- 

 don Treaty for the Limitation of ArmaTnents. 

 (64) 



standard port — British term for reference sta- 

 tion. 



standard sea water— /S'ee normal water. 



standard station — See reference station. 



standard temperature and pressure — (abbrevi- 

 ated S.T.P. ; also called normal temperature^ and 

 pressure.) . A phrase used in physics to indicate 

 a temperature of 0°C and a pressure of one 

 standard atmosphere. (5) 



standing crop — See biomass. 



standing floe — 1. A separate ice floe standing ver- 

 tically or inclined and enclosed by rather smooth 

 ice. (74) 

 2. See ropak. 



standing oscillation — See standing wave. 



standing stock — See biomass. 



standing wave — (or stationary loave, standing 

 oscillation) . A type of wave in which the sur- 

 face of the water oscillates vertically between 

 fixed points, called nodes, without progression. 

 The points of maximum vertical rise and fall are 

 called antinodes or loops. At the nodes, the 

 underlying water particles exhibit no vertical 



207-109 O— 66- 



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155 



