Zusammenfassung der Ressource
COASTS
- Types of waves
- Constructive
- Swash
- Constructive waves are waves that surge up the beach and have a
powerful swash · They carry large amounts of sediment and
'construct' the beach making it more extensive
- Destructive
- Backwash
- Destructive waves are named because they 'destroy' the beach or
coast. When the waves hit the beach they rear up and smash down
onto the beach. There is very little swash when the wave breaks but
has a powerful backwash.
- What is fetch?
- This is the distance the wind blows over the surface of the water
- What is deposition?
- When the sea loses energy, it drops the sand, rock particles and pebbles it has been carrying
- Longshore Drift
- Continual swash and backwash transports material sideways along the coast.
This movement of material often occurs in a zigzag
- What is a spit?
- Spits are also created by deposition. A spit is an extended stretch of beach material that projects out
to sea and is joined to the mainland at one end.
- How to make a spit?
- 1) Longshore drift moves material along the coastline. 2) A spit forms when the material is deposited.
3) Over time, the spit grows and develops a hook if wind direction changes further out. 4) Waves cannot
get past a spit, which creates a sheltered area where silt is deposited and mud flats or salt marshes
form.
- why are groups of people concerned about the coast?
- Erosion may be threatening beaches
or coastal settlements.
- People may want to develop tourism in the
area or existing tourism could be declining.
- There is a danger of flooding if
sea levels rise.
- There could be a problem with
sewage and/or pollution.