1.1.1: Operation of the coast as a system Flashcards
Inputs
4
Marine
Atmosphere
Humans
Terrestrial
Processes
3
Erosion
Deposition
Transport
Outputs
14
Beaches, sand dunes, spits, bars, tombolos, headlands, bays, cliffs, wave cut notches and platforms, caves, arches, stacks and stumps
Coastal system is a ? system
open system
Factors that make the coastal system an open system
inputs and outputs of energy and sediment
processes that operate as flows in the coastal system
river currents, ocean currents and tides,
atmospheric processes eg: wind
Sediment budget
Know the amount of sediment and where it comes from and is stored and how it leaves to manage coastlines.
Aeolian transfer
Process of wind eroding a coast
Movement of sediment is essential to
Stability of coasts
Outputs of the coastal system example
Longshore drift
Sediment equilibrium
volume of sediment in = volume of sediment stored + volume of sediment out
Net loss budget
Volume of sediment in < volume of sediment stored + volume of sediment out
Littoral cell aka
sediment cell
sediment cells have ? within
Small sub cells
Steady state equilibrium
Variations in energy stay mainly constant
Meta-stable equilibrium
Where an environment switches between 2 or more states of equilibrium, stimulated by some trigger
Dynamic equilibrium
Involves a change in equilibrium conditions but in a gradual manner over a longer period
example of steady state equilibrium
when and where sea cliffs receive equal atmospheric and marine energy
example of meta-stable equilibrium
high energy events like storms remove a whole beach in hours
example of dynamic equilibrium
sea level rise
Morphology
Shape of the land
Coastal morphology
Shape of the coast
Positive feedback
Change has knock on effects and spirals out of control
Negative feedback
Change happens then self corrects
example of positive feedback
erosion dune ridge by storm = driven further inland = new state of equilibrium reached
example of negative feedback
sand eroded during a storm erodes dunes at front then sand bars form which protect beach
Transfers
processes of erosion and transportation that can move sediment around the system
Stores
Sediment deposited in landforms
