Coasts As Natural Systems Flashcards
What type of system is a coast
Open
Example of negative feedback on a coast (3+)
Beach eroded
Cliff exposed to erosion
Sediment from cliff deposited on beach = grows
Positive feedback on coast (2+)
Beach = slows down waves
Can cause more sediment to be deposited = increasing size of the beach
Energy of coast (4)
Wind
Tides
Waves
Currents
Stores (2+)
Erosional landforms and processes
Depositional landforms and processes
Outputs of a coast (3+)
Dissipation of wave energy
Accumulation of sediment above the tidal limit
Sediment removed beyond local sediment cells
What’s the coastline of England and Wales divided into
Eleven sediment cells
What happens within a sediment cell (3+)
Sediment is largely recycled
Maintains a state of relative balance
Closed sediment systems
What’s a positive sediment budget (2+)
If inputs of sediment exceed outputs
The beach will extend in height, length and/or width
What’s a negative sediment budget (2+)
If outputs exceed inputs
Beach gets smaller
Reality of a sediment cell as a system (2)
Closed system but reality = slight loss of sediment to outputs beyond the system
If wave energy is very high sediment may transfer to neighbouring cell
What is a sediment sink
When sediment is permanently lost to the system
What is the back shore (2+)
Area between the high-water mark (HWM) and the limit of marine activity
Changes only usually take place here during storms
What is foreshore (2+)
Area between the HWM and the low water mark (LWM)
It is the most important zone for marine process
What is the nearshore
Area between the LWM and point where waves no longer have an effect on the land beneath them
