Coasts as Natural Systems Flashcards
What is a system? What type of system are coasts? - Coasts as Natural Systems
A system is an interconnected group of inputs, outputs, flows and stores which all combine for particular functions.
A coast is an open system.
What examples are there of inputs of energy and matter in coastal systems? - Coasts as Natural Systems
Inputs can be in the form of energy (from waves, wind, tides and sea currents) or matter (sediment, coastline geology, sea level change).
What are stores of components at the coast in terms of erosion? - Coasts as Natural Systems
Erosional landforms and landscapes comprise stores of eroded components.
What are stores of components at the coast in terms of deposition? - Coasts as Natural Systems
Depositional landforms and landscapes comprise stores of deposited components.
What are examples of outputs of energy and matter in coastal systems? - Coasts as Natural Systems
Outputs of energy can include dissipation of wave energy. Outputs of matter can include the loss of sediment into other sediment cells and the accumulation of sediment above the tidal limit.
What 4 natural processes produce energy at the coast? - Coasts as Natural Systems
At the coast, energy can be produced by waves, wind, tides and currents.
How can the relationship between a spit and a river estuary be seen as an example of positive feedback? - Coasts as Natural Systems
As sediment is deposited across an estuary by littoral drift, the river velocity slows down. This allows the spit to further grow across the estuary, even further slowing down the river velocity. The initial change is therefore exacerbated.
How can the erosion of a cliff leading to reduced wave energy be an example of negative feedback? - Coasts as Natural Systems
Erosion of the base of a cliff leads to a mass of material falling from a cliff. This is then able to crumble into the sea and absorb the wave energy, reducing the extent of future erosion.
What is a dynamic equilibrium? - Coasts as Natural Systems
A dynamic equilibrium is the balance between changing amounts of inputs and outputs.
Describe a constructive wave in terms of swash, backwash and wave height - Coasts as Natural Systems
Constructive waves have strong swash and weak backwash, low wave height, allowing them to carry sediment up a beach, building it up.
Describe a destructive wave in terms of swash, backwash, and wave height - Coasts as Natural Systems
Destructive waves have a weak swash and strong backwash, tall wave breaking downwards. They drag sediment away from a beach with their greater amounts of energy, therefore causing erosion.
