Geosci 105 - -tides are caused by pull of moon (2/3) and...

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-as the wave drags at the bottom. It slows and becomes more peaked. -waves break were ration fo wave height and ration of wave length -Three types of breaking waves -spilling breakers- form on relatively flat bottom with long distance of energy dissipation as crest spills over front of wave. -broad and extensive. -sea floor is very slowly getting shallower -plunging breakers- form on moderately steep bottoms; rapid curl and plunge of wave front with rapid energy dissipation -monster waves to catch for surfing -moderate sea floor become shallow -surging breakers- form on very steep (.15 degrees) slopes; do no actually break but surge forward, maintaining energy and often reflecting off seawalls, break waters. -brings wave back into ocean, doesn’t break -Ocean tide Theory – 3 parts Equilibrium Theory: -tides are caused by gravity and inertia -Newoton’s gravitation: -F=G(mearth x m moon)/r^2 -g- gravitational constant-6.67x 10^-11 m^3/(kg S^2) -Mearth&Mmoon=masses (in kg) -r=distance between their centers (in meters)
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Unformatted text preview: -tides are caused by pull of moon (2/3) and sun 91/3)-Sun far more massive, but much farther away- key additional factor is rotation of earth-moon system and the centrifugal forces on the ocean-There is not just one, but two opposing bulges-due to the centrifugal force of the earth spinning-A tidal month-28 day lunar cycle controls the tides timing. Since a day is 24 hours, the tide is 50 minutes later each day.-Tidal bulges follow lunar position-moon does not stay over equator- up to 28.5 degrees north or south-solar Influence: Spring and Neap Tides -Spring tides :when the lunar and solar tide are at the same place and = largest tide possible-Neap tides: when the moon and sun are at 90 degree angle, the tides partially cancel each other out. -Tidal records for a typical month-Spring tides: constructive interference (interference means either the sun adds to its self or it destructs and takes away from one another)...
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This note was uploaded on 03/16/2012 for the course GEOSCI 105 taught by Professor Tobin during the Spring '12 term at Wisconsin.

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