# EOS110 Mid-Final

 Basic features of surface water waves (7 items) Crest- High pointTrought- low pointwave length L distance between crestsfrequency f number of crest per secondPeriod T time between crestswave height h vertical distance from trough to crestspeed C horizontal rate of travel  Two wave speed formulas...relations between speed period and lenght                  f  frequencyL lenghtT periodC speed the motion of water in surface wave the water in a surface wave doesnt move, rather the wave crest and trough pass through if the wave is going to the right the orbital motion is clockwise.  These orbital motions are as deep as half the wave lenght The wave begins to stand and break when the orbitals feel the bottom charectoristics of waves free vs forced deep water vs shallow water free wave - opperates independent of its driving force i.e. storm swell or tsunamii keeps going after the force disipated Forced - will only contiue as long as the drving mechinism pertains. i.e. tidal wave is force dependent on gravity Deep water wave the depth of the water is greater then 1/2 the wavelengh for this reason tides are shallow water waves as the wavelengh can be up to 1/2 the diameter of earth Wave restoring force either surface tension and or gravity and in large scale coriolis surface tension stops small capilary wavesgravity is the restoring force of most other wavescoriolis effect and gravity aare the restoring force of large waves like tides. process of wave break 1. wave feels the bottom depth=1/2L2. wave stands as the energy is compresed into smaller area (due to shallow bottom)3. the bottom of wave slows while top continues at spped (same principal as refraction)4. wave aproaches the critical ratio of 1:7 height:lengh What forces create tides? (2) Gravity from the sun and moon tends to pull water towards thems centrifugal force tends to pull water away why is high tide not the same time/height every day because the tidal day is 24 hours and 50 minutes due to the rotation of earth and moon not the same height because the moon/sun not always in the same place and due to their relitive location paired with local geography tidal waves may be restricted 3 tide types and descriptions Diurnal - 1 high and one lowsemi-diurnal - two highs and two lows of same sizemixed - two highs and two lows of differing size what is an amphidronic point? a no-tide point in the center of ocean basin. as a tidal wave moves north it trends to the right due to coreolis, it is bounded to the right by the continent results in counter clockwise rotation around the amphridonic point spring tides vs neap tides spring tides - when moon and sun are in-line results in greater high/low tides neap tides - moon and sun at right angles why do some bays have very large tidal ranges 1. tides are greates at the boundries of the largest bodys of water.2. in a narrower bay there is no amphridonic point for it to rotate around so it all comes in then out. no circulation *3 in some locations the water in the bay may resonate or sieche at the same frequency as the tide creating an extremly large tide two main techniques for capturing tidal energy in line turbines in deep water barrage in bays what is and cuase eustatic sea level rise eustatic means world wideit rises due to- warming= more precipitationmelting= land ice melting into sea water*note that ice berg melting doesnt effect this as the iceberg is already dispacing its amount of water errosiaonal vs depositional coast errosional marked by tectonic uplift, storm activity, high wave energy volcanism passive marked by low energy, tectonicly passive areas lots of sandy features **typically the west coast is a more errosional active coast then the east river deltas wave dominated vs tide dominated tide dominated tend to have many chanels river dominated is one main channel with more deposition in a fan like shape. what creates el nino? the pressure systems near the equator change up, (typically low pressure in the east) spreads out along equator, disrupts the northeasterly trade winds which create the equatorial upwellings Authorspb83 ID213141 Card SetEOS110 Mid-Final DescriptionFrom Midterm to Final....Begining with Lecture 10 waves Updated2013-04-13T05:32:56Z Show Answers