the coastal system

Question 1

coastal system

Answer 1

open systems
- inputs: winds, waves, tides
- outputs: deposition further down coast
- flows/transfers: erosion, weathering, transportation

Question 2

constructive waves

Answer 2

• low frequency (4-6 waves per minute)
• powerful swash, weak backwash
• elliptical cross profile

Question 3

destructive waves

Answer 3

• higher frequency (8-10 waves per minute)
• weak swash, strong backwash
• circular cross profile, long fetch

Question 4

high energy coasts

Answer 4

• lots of rocky landforms
• high rates of erosion, low rates of deposition
• high inputs of energy from large, powerful waves

Question 5

low energy coasts

Answer 5

• very sandy beaches
• high rates of deposition, low rates of erosion
• low inputs of energy from small waves

Question 6

positive feedback at the coast

Answer 6

positive feedback = amplification of a change
waves erode the cliff, material is released
material contributes to abrasion of cliff face which exacerbates erosion at coast

Question 7

negative feedback at the coast

Answer 7

negative feedback = nullification of a change
sediment eroded on the beach is deposited, this causes increased deposition which contributes to rebuilding of the beach

Question 8

sediment cells

Answer 8

stretch of coastline, bounded by two headlands, primarily described as closed systems as rarely any inputs or outputs, sediment movement is predominantly within the coastal cell
11 sediment cells within the UK

Question 9

sediment budget

Answer 9

balance between inputs and outputs of sediment within a coastal system
coastal systems must be in a state of balance - dynamic equilibrium
human activity and natural variation can disrupt state of balance