Tides

STUDY
PLAY

Terms in this set (...)

amphidromic point
the node(s) near center of an ocean basin; no tide pt in the ocean around which tidal crest rotates through 1 tidal cycle
astronomical tide
tides caused by inertia & the gravitational force of the sun & moon
diurnal tide
tidal cycle of 1 high tide & 1 low tide per day
dynamic theory of tides
model of tides that takes into account the effects of finite ocean depth, basin resonances, & the interference of contintents on tide waves
ebb current
water rushing out of an enclosed harbor or bay due to the fall in sea level as a tide trough approaches
equilibrium theory of tides
model of tides that considers Earth to be covered by an ocean of great & uniform depth capable of instantaneous response to the gravitational & inertial forces of the sun & moon
flood current
water rushing into an enclosed harbor or bay die to the rise in sea level as a tide crest approaches
high tide
high-water position corresponding to a tidal crest
low tide
low-water position corresponding to a tidal trough
lunar tide
tide caused by gravitational & inertial interaction of the moon & Earth
mean sea level
the height of the ocean surface averaged over a few years' time
meteorological tide
a tide influenced by the weather. Arrival of a storm surge will alter the estimate of a tide's height or arrival time, as will a strong , steady onshore or offshore wind
mixed tide
a complex tidal cycle, usually with 2 high tides & 2 low tides of unequal height per day
neap tide
time of smallest variation between high & low tides occurring when Earth, moon & sun align at right angles; alternate with spring tides, occurring at 2 week interverals
semidiurnal tide
a tidal cycle of 2 high tides & 2 low tides each lunar day, with the high tides of nearly equal height
slack water
a time of no tide-induced currents that occurs when the current changes direction
solar tide
tide caused by the gravitational & inertial interaction of the sun & Earth
spring tide
time of greatest variation between high & low tides occurring when Earth, moon, & sun form a straight line; alternate with neap tides, occurring at 2 week intervals
tidal bore
a high, often breaking wave generated by a tide crest that advances rapidly up an estuary or river
tidal current
mass flow of water induced by the raising or lowering of sea level owing to passage of tidal crests or troughs
tidal datum
the reference level (0,0) from which tidal height is measured
tidal range
difference in height between consecutive high & low tides
tidal wave
the crest of the wave causing tides; another name for tidal bore
tide
periodic short term change in the height of the ocean surface at a particular place, generated by long wavelength progressive waves; caused by interaction of gravitational force & inertia. Movement of Earth beneath tide crests results in the rhythmic rising & falling of sea level