STATIC PRESSURE . The static pressure at a point is 

 the pressure that would exist at that point in the 

 absence of sound waves, (1) 



STATION . In oceanography, the geographic location 

 at which any set of oceanographic observations was 

 taken; also, the observations recorded at the loca- 

 tion. The appropriate verbal phrase is "occupy a 

 station". (12) 



STATIONARY WAVE . A wave that oscillates about an 

 axis without progressing. Such a wave may be il- 

 lustrated by the oscillation of the water in a pan 

 that has been tilted. Near the axis, which is 

 called the node or nodal line, there is little or 

 no vertical rise and fall of the water. The ends 

 of the waves are called LOOPS and at these places 

 the vertical rise and fall is a maximum. The 

 period of a stationary wave depends upon the length 

 and depth of the body of water and may be expressed 



by the formula, P •= 2L/v^d7 in which P is the 



period, L the length, d the depth and g the accel- 

 leration of gravity on the earth's surface. A 

 stationary wave may be resolved into two progres- 

 sive waves of equal amplitude and equal speeds 

 moving in opposite directions, the length of each 

 PROGRESSIVE WAVE measured from crest to crest being 

 twice as great as the resultant stationary wave 

 measured from loop to loop. (14) 



STATIONARY-WAVE THEORY . An assumption that the 

 basic tidal movement in the open ocean consists of 

 a system of stationary wave oscillations, any 

 PROGRESSIVE WAVE movement being of secondary impor- 

 tance except as the tide advances into tributary 

 waters. The continental masses divide the sea into 

 irregular basins, which, although not completely 

 enclosed, are capable of sustaining oscillations 

 which are more or less independent. The tide-pro- 

 ducing force consists principally of two parts, a 

 semidiurnal force with a period approximating the 

 half day and a diurnal force with a period of a 

 whole day. In so far as the free period of oscil- 

 lation of any part of the ocean, as determined by 

 its dimensions and depth, is in accord with the 

 semidiurnal or diurnal tide-producing force, there 

 will be built up corresponding oscillations of con- 

 siderable amplitude which will be manifested in 

 the rise and fall of the tide. The diurnal oscil- 

 lations, superimposed upon the semidiurnal oscil- 

 lations, cause the inequalities in the heights of 

 the two high and the two low waters of each day. 

 Although the tidal movement as a whole is somewhat 

 complicated by the overlapping of oscillating areas, 

 the theory Is consistent with observational data. 

 (14) 



STATION BUOY . A buoy used to mark the approximate 

 position of an important buoy or lightship should 

 it be carried away or temporarily removed. Also 

 called marker buoy, watch buoy. (17) 



STAVE . Individual longitudinal elements, a number 

 of which make up a sonar transducer. (7) 



STD. An instrument for continuously measuring the 

 temperature, electrical conductivity and depth. It 

 automatically determines water salinity from the 

 temperature-conductivity-salinity relationships . 



STEADY-STATE VIBRATION . Steady-State vibration 

 exists in a system if the velocity of each particle 

 is a continuing periodic quantity. (2) 



STENOHALINE . Term used to indicate a narrow range 

 of salinity values, and is frequently used to 

 describe marine organisms which are sensitive to 

 small changes in salinity. Stenohaline animals are 

 especially characteristic of deep water and of the 

 open sea where the salinity ranges only between 

 about 34 to 36 0/00. It should not be understood, 

 however, that stenohaline animals are confined to 



the open sea or the above salinity range. The 

 term euryhaline is used to indicate those organisms 

 which have a great degree of tolerance to wide 

 range of salinity. The euryhaline animals are 

 naturally characteristic inhabitants of the coastal 

 regions and of estuaries, but due to their toler- 

 ance are represented in the open sea as well. 

 Along this same line stenothermic and eurythermic 

 animals are those capable of tolerating narrow or 

 wide ranges of temperature respectfully. Among 

 the stenothermic animals their are those which are 

 cold-limited (phychrophlle) and those which are 

 warmth-limited (thermophile) . Although some ani- 

 mals are either stenothermic or eurythermic 

 throughout life, many others are eurythermic with 

 respect to one phase of the life cycle and steno- 

 thermic at another phase. For the latter type it 

 is necessary to distinguish between reproductive 

 euryhaline or stenohaline during spawning periods 

 or during the egg or larval developmental stages, 

 and vegetative euryhaline or stenohaline during 

 all other periods of life. (13) 



STENOTHERMIC . See STENOHALINE. 



STILL WATER LEVEL (UNDISTURBED WATER LEVEL) . The 

 surface of the water if all wave and wind action 

 were to cease. In deep water this level approxi- 

 mates the midpoint of the wave height. In shallow 

 water it is nearer to the trough than the crest. 

 (27) 



STOKES IAN WAVE . See DEEP-WATER WAVE. 



STOKES'S LAW . A relation which gives the terminal 

 fall velocity reached by a small sphere falling 

 freely under gravity in a viscous medium. The 

 relation between the terminal velocity of the 

 sphere v-p and the frictional force f arising 

 from the viscosity of the medium is given by 

 f =6Ti^irvrp, where /J is the dynamic viscosity 

 and r is the radius of the sphere. Stokes's law 

 holds with fair accuracy for motion in air provided 

 that the diameter of the sphere does not exceed 

 about 0.008 cm. It fails completely for larger 

 bodies, such as raindrops, which require considera- 

 tion of the turbulence induced in the medium by 

 the passage of the drops. 



When the frictional force is equated to the 

 force due to gravity, the resulting expression for 



the terminal velocity is 2 2 



v-j. = g r g (p - po)/M, 



where g is the acceleration of gravity and p and 

 po are the density of the sphere and of the 

 medium, respectively. For sufficiently small 

 spheres, this velocity is so small that the par- 

 ticle may be said to be in suspension, (24) 



STONES . Detached particles of rock usually smaller 

 than 10 inches (256 millimeters) in diameter. 

 Stones are classed as gravel on bottom sediment 

 charts . 



STOR . Scripps Tuna Oceanographic Research. 



STORAGE SYSTEM . Scanning system in which the re- 

 ceived signal from each direction is integrated in 

 the capacitors associated with each of many direc- 

 tional channels for later sampling. (7) 



STORIS . The largest pieces of polar ice drifting 

 along the Greenland coast from the Arctic Ocean. 

 (17) 



STORM ICE FOOT . An ice foot produced by the break- 

 ing of a heavy sea or the freezing of wind-driven 

 spray. (17) 



STORM WAVES (STORM SURGES) . Severe storms may be 

 accompanied by exceptionally high water called 

 storm waves or storm surges. Three effects in a 

 storm induce a rise in sea level. The first is 

 wind stress on the sea surface, which results in a 



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