Anatomy of a Wave A wave is the motion of a form that carries energy from one place to another The 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 Wave

Ocean waves are generated when wind flows over water The wind drags across the water, starting the formation of a wave If the wind is fairly continuous, then the wave built will be larger A group of large wave is called a Swell

Wave Size Factors that affect the size of a wave: Wind speed Faster wind kicks up larger waves Duration 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 Shore As waves reach shallower water they begin to break up Bottom 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 Shore After 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 currents Very strong undertows that pull water directly back into the sea Strong enough to break through incoming waves

Waves and the Shore As 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 currents Longshore currents help to straighten out shorelines, develop sandbars, and barrier islands