Waves + tides
what are the distubing and restoring forces of different wave types?
(look in book)
what are the three basic types of tides and descibe them
-Diurnal tides: one high and one low tide every 24 hours -Semidiurnal tides: two high and two low tides every 24 hours of equal magnitude -Mixed tide: two high tides and two low tides every 24 hours of differing magnitude
what is a wave train and how does it behaves
-a group of waves with the same wavelength -leading waves are drained of energy and dissappear, new waves are created at the end of the wave train
the equation that relates wavelength, period, and speed in deep-water waves and how these parameters change over long distances and as deep-water waves move into shallow water
-deep-water equation: depth greater than half the wavelength(d>(L/2)) -as waves move from deep to shallow water, their period (T) stays the same but their speed (c) and wavelength (L), decrease -shallow-water waves (d<(L/20)
what are the three different flow phases of a tide that is within an enclosed area
-flood current: water rushing in -ebb current: water rushing out -slack water: a time of no currents
what are spring and neap tides
-spring tide: the highest and lowest tides, when the sun an moon are in alignment with earth -neap tide:the smallest changes between high and low tide ( the lowest high tide and the highest low tide) when the sun and moon are in a perpendicular to each other
what is dispersion?
-the process of wave separation by size (wavelength)
what are wavelength, height, frequency, and period
-wavelength:distance between two adjacent wave crests -height: crest and trough -frequency: # of wave crests passing point A or point B each second -period: time required for wave crest at point A to reach point B
what are internal waves? Where can you find them?
-waves that form at the boundary between water of different densities
why do waves break and in what conditions this happens
When their height becomes 1/7 of their wavelength (or when the ratio of their height to wavelength is 1/7)
what is an amphridromic point
a point of no tidal motion which a tidal crest rotates around
what is a seiche and what causes it?
a seiche occurs when water sloches back and fourth in a closed basin, like a lake, it occurs dur to changes in atmos. pressure (most common) storm surge or tsunami
What is a standing wave and what causes it?
a standing wave is a wave that osicallates around a single node, the wave has crests and troughs in a fixed position. This occurs when a wave strikes an obstacle directly and the reflected waves interfere w/ the oncoming waves
what is transported by waves
energy
how has tidal friction affected the rotation of the earth over time
it has slowed the rotation of the earth from 22 hours/day to 24 hours/day
what are the smallest and largest waves?
smallest: capillary waves largest: tides
what does the dynamic theory of tides take into account
that tides are waves and so have certain behaviors in shallow water and that continental also have an effect
what does the equilibrium theory of tides assume
the seafloor doesnt influence tides and there are no interfering continents
what is stokes drift
the small net transport of water in the direction of a wave
what is fetch?
the uninterpreted distance over which wind blows
What is a fully-developed sea?
when we observe the maximum wave size possible for the wind speed, duration, and fetch