Coasts Flashcards
What is a sediment cell?
A distinct area of coastline separated from other areas by well-defined boundaries
What is a fetch?
The maximum length of open water over which the wind can blow
How are waves formed?
The wind tugs at the surface of the water causing the wave shape to move. When the wave moves into shallow water near the coast it breaks and friction occurs between the base of the wave and the seabed, allowing the wave to move forward.
What is a constructive wave?
A constructive wave is where the swash is greater than the backwash and therefore greater deposition takes place.
What is a destructive wave?
A destructive wave is where the backwash is greater than the swath and therefore more erosion takes place.
What is a longshore current?
When a wave reaches a beach or coastline it releases a burst of energy that generates a current which runs parallel to the shoreline.There affected by the velocity and angle of the wave.
What is a recurrent?
Rip currents may form around low spots or break in sandbars. A localised current that flows away from the shoreline towards the ocean perpendicular to the shoreline.
What is upwelling?
Winds blowing across the ocean surface often push water away from an area. When this occurs, water rises up from beneath the surface to replace the diverging surface water.
What is the Coriolis effect?
The Earth rotates and circulating air is deflected. The coriolis effect tries to force winds to shift towards the right or left.
How are tides formed?
Tides are caused by the gravitational pull of the moon on the water of our planet. When the earths surface is close to the moon it pulls on the water and causes it to rise up giving high tide. When the earths surface is far away, impact of this gravitational pull is less and we get low tide.
What is a springtide?
The periods during the year when the gravitational pull of the moon is at its maximum gives the highest tides.
What is a neap tide?
The periods of the year when the gravitational pull of the moon is at its minimum and gives the lowest tides.
What factors affect wave energy?
The strength of the wind, the duration of the wind and the fetch.
What is formed a high energy coastlines?
Erosional landforms such as headlands cliffs and wave cut platforms.
What is formed at low energy coastlines?
Beaches, spits and coastal plains
