Ocean Waves Essential Question How does ocean water work? Objectives Identify parts of a wave...

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Ocean WavesEssential Question

How does ocean water work?

ObjectivesIdentify parts of a waveExplain the process that causes waves to breakDescribe different ocean currents

WavesA wave is a rhythmic movement that carries

energy through matter or space.As a wave passes, only energy moves

forward, while the water molecules move around in circles and stay near their original position.

Waves are created by friction from wind.

Wave Characteristics

Wave CharacteristicsThe crest is the high point of a wave.The trough is the low point of a wave.Wavelength is the horizontal distance

between the crests or between the troughs of two waves.

Wave height is the vertical distance between crest and trough.

Half the distance of the wave height is called the amplitude of a wave.

Wave HeightDepends on three

factors:Wind SpeedWind DurationFetch

Expanse of water wind blows across

BreakersWaves lose energy and slow down as they reach

the shore, due to friction with the beachIncoming crests catch up to slower crests aheadsmaller crest-crest wavelengthWaves become higher, steeper, and unstableThe crests collapse forward

Wave Breaking

Ocean CurrentsDensity Current

Due to difference in temp. and salinityMove slowly in deep ocean waters

Surface CurrentWind-drivenWest to east due to prevailing westerlies

UpwellingUpwelling is the upward motion of ocean

waterWater is cold because it originates from the

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