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to whether it is reckoned from the local, standard, or Spitsbergen Atlantic Current A current setting
Greenwich meridian. northwestward off the southwest coast of Spitsbergen in
solitary wave A wave of translation consisting of a the Greenland Sea.
single crest rising above the undisturbed water level spring high water Same as mean high water springs
without any accompanying trough. The rate of advance of (MHWS). See spring tides.
a solitary wave depends upon the depth of the water and is spring low water Same as mean low water springs
usually expressed by the formula: (MLWS). See spring tides and mean low water springs.
C = g(d + h) spring range (Sg) See spring tides.
in which C = rate of advance, g = acceleration of gravity, d spring tides or tidal currents Tides of increased
= depth of water, and h = height of wave, the depth and range or tidal currents of increased speed occurring
height being measured from the undisturbed water level. semimonthly as the result of the Moon being new or full.
solstices The two points in the ecliptic where the The spring range (Sg) of tide is the average range occurring
Sun reaches its maximum and minimum declinations; also at the time of spring tides and is most conveniently
the times when the Sun reaches these points. The maximum computed from the harmonic constants. It is larger than the
north declination occurs on or near June 21, marking the mean range where the type of tide is either semi diurnal or
beginning of summer in the Northern Hemisphere and the mixed, and is of no practical significance where the type of
beginning of winter in the Southern. The maximum south tide is predominantly diurnal. The average height of the
declination occurs on or near December 22, marking the high waters of the spring tides is called spring high water
beginning of winter in the Northern Hemisphere and the or mean high water springs (MHWS) and the average
beginning of summer in the Southern. height of the corresponding low waters is called spring low
solstitial tides Tides occurring near the times of water or mean low water springs (MLWS).
the solstices. The tropic range may be expected to be stand of tide Sometimes called a platform tide. An
especially large at these times. interval at high or low water when there is no sensible
Somali (East Africa Coast) Current An Indian change in the height of the tide. The water level is
Ocean current setting southwestward along the coast of stationary at high and low water for only an instant, but the
Somalia. The current reverses and sets to the northeast change in level near these times is so slow that it is not
during the Southwest Monsoon. usually perceptible. In general, the duration of the apparent
South Equatorial Current A current setting west- stand will depend upon the range of tide, being longer for
ward along and south of the Equator in the Atlantic and a small range than for a large range, but where there is a
Pacific Oceans, and south of the Equator in the Indian tendency for a double tide the stand may last for several
Ocean. It occurs immediately south of the Equatorial hours even with a large range of tide.
Counter Current. standard method A tidal datum computation
Southwest Monsoon Current Same as Monsoon method. Generally used for the West Coast and Pacific
Current. Island stations. Values needed are mean tide level (MTL),
species of constituent A classification depending mean range of tide (MN), great diurnal range (GT), and
upon the period of a constituent. The principal species are mean diurnal high and low water inequalities (DHQ and
semidiurnal, diurnal, and long-period. DLQ) as determined by comparison with an appropriate
specific volume anomaly, or steric anomaly control. From those, the following are computed:
( ) The excess in specific volume over the standard MLW = MTL - (0.5*MN)
specific volume at 35 0 , 0°C, and the given pressure. See MHW = MLW + MN
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MLLW = MLW - DLQ current for the purpose of distributing and grouping them
MHHW = MHW + DHQ into constituent hours preliminary to summing for har-
standard time A kind of time based upon the transit monic analysis. See Coast and Geodetic Survey Special
of the Sun over a certain specified meridian, called the Publication No. 98, Manual of Harmonic Analysis and
time meridian, and adopted for use over a considerable Prediction of Tides. This analysis is now performed on
area. With a few exceptions, standard time is based upon electronic digital computers.
some meridian which differs by a multiple of 15° from the steric anomaly Same as specific volume anomaly.
meridian of Greenwich. The United States first adopted stilling well A vertical pipe with a relatively small [ Pobierz całość w formacie PDF ]