Unit Five - Weathering and Erosion - Waves Flashcards
1
Q
What are Waves?
A
The up and down motion of water in the ocean
(Due to Wind)
2
Q
What is the process of waves? (6)
A
- Wave moves towards the shore
- Ocean becomes shallow
- Bottom of the wave drags along the ocean floor
- Causing it to slow.
- The top continues at the same speed
- The wave becomes unstable and “breaks”
3
Q
What is a Longshore Current? (7)
A
- Ocean current flows parallel and close to the shore
- Because of zigzag wave pattern.
- Think of a sediment resting at a beach
- The prevailing wind causes a wave to approach the shore at an angle
- Retreats back to the ocean perpendicular to the shore
- That sediment is carried along with it
- Overtime, the sediment is deposited to the other side of the shore
4
Q
What are Groynes? (4)
A
- Designed to reduce coastal erosion
- Traps the transported sediment from Longshore Drift
- One side of the groin is filled with deposited sediment
- Encourages a wide beach that absorbs wave energy
5
Q
How do you know in which direction a wave flows through groynes?
A
The wave moves towards the side of the groin where there is less buildup of sediments.
6
Q
What are Barrier Islands? (4)
A
- A long narrow island
- Made of buildup of sediment
- Parallel to the mainland
- Caused by Longshore Current