waves and tides - mr. boettcher's class · what is a wave • there are different types of...

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Waves and Tides Sec$on 2.1 p. 349-354

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Waves and Tides Sec$on2.1p.349-354

Learning Outcomes • Describinghowwavesand$desaregeneratedandhowtheyinteractwithshorelines

What is a Wave •  Therearedifferenttypesofwaves,butthemovementforallofthemisfairlysimilar(Theyhavetroughsorcrests)

• WaterWavesarechangesinpa/ernsthatmovealongthewater’ssurface•  Althoughthewavewilltravelveryfardistances(100’sofkmiftalkingaboutanocean)thewateritselfdoesnotmoveveryfar

Causes of Waves • Mostwavesarecausedbythewind•  Thestrongerthewindthebiggerthewave

•  Inlargerdeepwaterwavesthemo$onwillseemupanddown• Asthewavegetstoshallowerwater,theboIomdragsslowingitdown,andthetopsofthewaveareabletobreakcrashingontotheshore

Effects of Waves on Shorelines •  TheforceofwavescrashingagainstashorelinecanchangetheshapeoftheshorewhetheritshardrockorsoKsand•  Largewaveserodeawaytheshore•  Smallwavesmovegentlyontotheshore,anddepositsandorothermaterialsneartheshore

Tsunamis (Harbor Wave) • ArecreatedbyEarthquakes(seismicwaves),orundergroundvolcanoerupGons•  Theresultishugeoceanwaves(TidalWaves),thatarelargeandspreadoutoverlongdistances•  Notveryno$ceableinopenocean•  Inshallowerwatercanriseashighasa15storybuilding

Theenergyoriginatesen$relyinthewater,meaningtheforceistravelingthroughthewater

Tides •  Tidereferstothedailychangeintheoceanswaterlevel•  Twotypes

•  HighTide:waterlevelatitshighest•  LowTide:waterlevelatitslowest

•  TidesoccurduetogravityTwiceaday(12hoursand50minutes)•  ThemoonsgravitypullingontheearthcreatehighGde•  Thelackofgravitypullingontheoppositesideoftheglobe(waterbulges)

• Highandlow$dearealwaysoccurringatdifferent$meseachday,sopeopleuse$detablestoknowwhenthe$deswilloccur