Ocean Waves

Anatomy of a WaveA wave is the motion of a form

that carries energy from one place to anotherThe form is what moves, the

material that the wave moves through does not move much.

The wave form is characterized by: Amplitude, measured from

midline Wavelength, measured between

identical points of motion Frequency, a count of how many

wavelengths pass a fixed point in 1 second

Anatomy of a WaveThe speed of most waves is

determined by the material that the wave is moving through.

The speed is calculated using:

Wherev is velocity, in m/sf is frequency, in Hzλ is wavelength, in m

Anatomy of a WaveOcean waves are generated when wind flows

over waterThe wind drags across the water, starting the

formation of a waveIf the wind is fairly continuous, then the wave built

will be largerA group of large wave is called a Swell

Wave SizeFactors that affect the size of a

wave:Wind speed

Faster wind kicks up larger wavesDuration of wind

Long duration, stead winds create larger waves

Fetch Distance available for the wind to

work over Large fetches produce large

waves

Waves and the ShoreAs waves reach

shallower water they begin to break upBottom of wave

scrapes along seafloor, and slows down

Top continues to move forward quickly, and begins to curl over

Once top is too far ahead, the wave breaks

Waves and the ShoreAfter the wave breaks,

the water is drawn back away from shore by undertow currents

If the waves are large enough, the undertow currents can develop into rip currentsVery strong undertows

that pull water directly back into the sea

Strong enough to break through incoming waves

Waves and the ShoreAs waves approach the shore,

they nearly always bend to head straight into shore

This bending causes water beneath the waves to flow parallel to the shoreline. This can create longshore currentsLongshore currents help to

straighten out shorelines, develop sandbars, and barrier islands