Geo - Waves

Waves

• Waves are essentially the movement of water molecules
• within the ocean.
• They involve the circular orbit of water molecules and are the
• agents of coastal change.
• Waves are created by the action of the wind blowing
• over the sea or ocean.
• The friction from the wind causes the surface water
• to move in ripples which eventually form full waves.
• The stretch of ocean
• water over which the wind blows is called the FETCH.
• Generally, the longer
• the fetch the larger the wave, and the faster the wind speed the larger the wave
• (this is why we generally get the largest waves during and just after storms).
• 

Constructive Waves

• 
• Constructive waves build beaches
• They are created in calm weather and are less powerful than destructive waves
• They have a long wavelength, and are low in height.
• For this wave the swash is bigger than the backwash so therefore material gets pushed up and are accumulated rather than the deposited material being removed

Destructive Waves

• 
• They are created from big, strong waves when the wind is powerful and has been blowing for a long time.
• They occur when wave energy is high and the wave has travelled over a long fetch.
• They have a short wave length and are high and steep.
• In this wave the backwash is bigger than the swash so more material is being is being eroded
• This type of wave have steeper profiles, larger and higher wave crests and come more frequently a