Coasts Flashcards
Inputs to an open system
- Energy from: Waves, Wind, Tides, Sea currents
- Sediment
- Geology of coastline
- Sea level change
Stores of an open system
Erosional/depositional land forms and landscapes
Outputs of an open system
- Dissipation of wave energy
- Accumulation of sediment above the tidal limit
- Sediment removed beyond local cells
Dynamic Equilibrium
- A state of balance between continuing processes.
- Balance of inputs and outputs
Benefits of using a systems approach
- Helps us to predict the possible consequences of natural processes or human interventions
- Can explain variations and changes that occur along a coastline
- Can help foresee positive or negative impacts of a plan
How many cells surround the UK
11
Example of negative feedback
- Cliff erosion leads to slumping
- The mass of the collapsed material at the base of the cliff will protect the base of the cliff from further erosion and retreat
- Changes in the system reduce the causes of further disruption
Example of positive feedback
- A spit extends across a river estuary
- Reduces river velocity due to greater friction
- Could lead to further spit growth and therefore further reduction in river velocity
Negative sediment budget
Outputs exceed inputs
4 sections of a coastline
-Backshore:
Area between high water mark and the limit of marine activity
-Foreshore:
Area between the high water mark and the low water mark
-Nearshore:
Area between the low water mark and the point where waves no longer have an effect on the land beneath them
-Offshore:
Area beyond the point where waves cease to have an impact upon the seabed
Erosion definition
The wearing away of the Earth’s surface by the action of ice, wind and water
Weathering definition
The breakdown of decay of rock at or near the Earth’s surface in its original location (in situ)
Prevailing wind direction in the UK
South-west
