storm surge storm surge: the abrupt bulge of water driven ashore by a storm
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Seiche: Pendulum-like rocking of water in an enclosed areaFor example: water sloshing in a bucket,
bathtub or bay
Causes of Seiches:WindsChange in atmospheric pressure
Example: Lake Geneva Constant breezes pushed the water to one end
of the lake. When the wind subsided, the water is released to rock back and forth
Tsunami or Seismic Sea Waves: Long-wavelength, shallow-water progressive waves caused by the rapid displacement of ocean waterJapanese: Tsu = harbor, nami = waveTsunami caused by the suddeen vertical
movement of Earth along faults are properly called seismic sea waves
can also be caused by landslides, icebergs falling from glaciers, eruptions, and other displacements
Due to the extremely low steepness and the waves very long period, a tsunami will pass unnoticed beneath ships at sea (1 to 2 feet total wave height)
At shore the wave height greatly increases (as high as 100 feet)
The wave is a fast, onrushing flood of water, not the huge, plunging breaker of popular folklore
http://www.asiantsunamivideos.com/Tsunami Warning Network
Tides: periodic, short-term changes in the height of the ocean surface at a particular place caused by a combination of the gravitational force of the moon and the sun and the motion of the EarthWith a wavelength that can equal half of
Earth’s circumference, tides are the longest of all waves.
Forced waves: never free of the forces that cause them
In case you didn’t know:The Earth and the moon do not smash into
each other because they are in a stable orbitThe Earth-moon system revolves once a month
(27.3 days) around the system’s center of mass
High tide: The high water position corresponding to a tidal crest
Low tide: The low water position corresponding to a tidal crest
Lunar tide: tides caused by gravitational and inertial interaction of the moon and Earth Tidal day: 24 hours and 50 minutes (each tide
arrives 50 minutes later each day)Also, the moon does not stay right over the equator
throughout the year, tides fluctuate depending on location
Solar Tide: caused by the gravitational and inertial interaction of the sun and Earth
Spring Tide: large tides caused by the linear alignment of the sun, Earth, and moon. Occur at two-week intervals corresponding to the new and full moons. Very high high tides and very low low tides
Neap Tide: occur when the moon, Earth, and the sun form a right angle. Also occur at two-week intervals but with not very high high tides and not very low low tides
As Earth turns, land masses get in the way The shape of the ocean basin also has an
influence, combined they create:Semidiurnal Tides: two high tides and two
low tides of nearly equal level each lunar dayDiurnal Tides: one high and one low