tides tide producing forces semi-diurnal; diurnal tides lunar and solar tides resonance shallow...
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Tides
Tide producing forces
Semi-diurnal; diurnal tides
Lunar and solar tides
Resonance
Shallow water waves
Tidal ellipses
Tidal residuals
Tidal-stream selective transport
By the time the Earth has completed one revolution (one day), the moon has moved slightly, so the Earth needs to rotate a bit more to catch up with the moon…
Main Tidal constituents
Origin Symbol period coefficient generation (hours) Semidiurnal tides
Moon M2 12.42 0.91 semidiurnal principal lunar tideSun S2 12.0 0.42 semidiurnal principal solar tideMoon N2 12.66 0.17 elliptical M2 tide Diurnal tidesM&S K1 23.94 0.53 principal declination tideMoon O1 25.82 0.38 diurnal principal lunar tideSun P1 24.07 0.18 diurnal principal solar tide
Kelvin wave: propagates with the coast on its right in the northern hemisphere and its amplitude decays offshore
Tidal Resonance: amplification of tidal signal (e.g., amplitude) that occurs in an embayment or on a shelf, when the “length” of the embayment or shelf is near one-quarter of the wavelength of the wave.
Deep water waves: Wavelength short relative to water depth
Shallow water waves: Wavelength long relative to water depth
Tidal currents – can be very complicated (from near Australia)
Current hodographshows directionand speed of slow every hour(each point) over15 days. Patterndoesn’t even repeat!
Plaice migration: as adults they migrate from the feeding areas to the spawning grounds and back.
How do they do it?
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