Case Studies Flashcards
Backshore
This is the area between the high water mark and the landward limit of marine activity.
Foreshore
This is the area lying between the high water mark and the low water mark and is often seen as the most important area for marine activity.
Inshore
he area between the low water mark and the point where the waves cease to have any influence on the land around them.
Offshore
The area beyond the point where waves cease to impact the seabed and in which activity is limited to the deposition of sediments.
Terrestrial
Rock type of the coast. If the coast is made from soft rock, it will be eroded far more quickly than if it is made of hard rock.
Deltas form where rivers meet the sea, which will alter the shape of coasts.
Composition of rock layers on coasts will affect their shapes.
Tectonics in the area will effect coasts. Earthquakes can move rock and trigger tsunamis, which can destroy entire coastlines.
Mangroves and coral reefs can alter the shape of coasts as they slow down incoming waves, decreasing the rate at which a coast is eroded.
Human
Human
Ports, docks and transport can be constructed and/or used on coasts, thus altering the shape of coasts. Boats can destroy coral reefs and hence increase the erosion of the coastline.
Coasts can be used for recreation and tourism. The increased foot traffic and demand for certain attractions on coastlines can alter their shape substantially.
Humans can settle on coastlines. Often, settlements on coastlines will thrive due to their proximity to the sea for trade and tourism.
Global warming is altering the shape of coastlines due to the rising sea levels resulting from it.
Atmospheric
The cliff sub system
Inputs: subaerial processes
Transfers: cliff collapse
Outputs: transportation of sediment
The beach sub system
Inputs: accumulation of sediment from longshore drift
Transfers: transportation of sand by wind
Outputs: removal of sediment by destructive waves
Sediment cells
A sediment cell can be defined as a length of coast and its nearshore area within which the movement of sediment is self contained
A Sediment budgetrefers to the balance betweensedimentadded to and removed from the coastal system
When more material is added than is removed, there is a surplus of sedimentand the shore builds seaward
The boundaries of the sediment cells tend to be headlands and peninsulas as they act as natural barriers to stop the further movement of the sediment
Dynamic equilibrium
The balanced state of a system when its inputs and outputs are equal. Sediment cells help the coastal environment achieve this state.
But, if one element changes, for example a decrease in the supply of sediment within a cell because of coastal management, this upsets the equilibrium and affects other components of the system, for example increased erosion.
By a process of feedback, the system adjusts to the change and regains equilibrium.
Destructive and constructive waves are another good example of the coast working towards equilibrium
