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Originally from here - https://quizlet.com/gb/698259891/ocr-a-level-geography-coastal-landscapes-flash-cards/?funnelUUID=4eeccf70-5a09-4725-8198-afe9d8476428
System
set of interrelated objects comprising components and processes that are connected together to form a unified whole
Types of energy available to coastal landscape system
Kinetic
Potential
Thermal
Geomorphic Processes
Natural mechanisms of weathering, erosion and deposition that modify landforms
Open System
Energy and matter can be transferred from neighbouring systems as an input as well as to other neighbouring systems as an output.
Inputs to a coastal system
Kinetic energy from wind and waves
Thermal energy from heat of sun
Potential energy from position of material on slopes
Material from marine deposition, weathering and mass movement
Outputs from a coastal system
Marine and wind erosion from beaches and rock surfaces
Evaporation
Throughputs in a coastal landscape system
Stores e.g. beach and nearshore sediment accumulation
Flows e.g. longshore drift
Equilibrium
Rate of sediment accretion is equal to rate of sediment removal
When a systems inputs and outputs are equal
Dynamic equilibrium
when equilibrium is disturbed the system undergoes self-regulation changes in order to restore equilibrium.
Sediment Cell
Stretch of coastline and its associated nearshore area within the movement coarse sediment, shingle and sand is self-contained.
Example of sediment cell
River Thames
Why is it unlikely that sediment cells are completely closed?
Variations in wind direction and presence of tidal currents
Sub-cells within the major sediment cells
Milennia
Thousands of years
Aeolian
Wind
Wave height formula
0.36 square root of fetch
What three factors dictate the size and direction of a wave
Wind speed
Wind duration/fetch
Wind direction
Amount of energy in a wave in deep water.
P = H2T
Crest
Highest surface part of a wave.
Trough
Lowest part of a wave.
Wavelength
Horizontal distance between two adjacent crests or troughs.
Swell waves
waves generated in open oceans that can travel huge distances.
Storm waves
Locally generated waves with short wavelength, greater height and shorter wave period.
Spilling waves
Steep waves breaking onto gently sloping beaches
water spills gently forwards as the wave breaks
Plunging waves
Moderately steep waves breaking onto steep beaches
water plunges vertically downwards as crest curls over.
Surging waves
Low-angle waves breaking onto steep beaches
the wave slides forward and may not actually break.
How are waves created?
Frictional drag of winds over ocean surface
Wave frequency
Number of waves per minute
Process of wave break
Waves slow down as they encounter friction with sea floor
Wavelength decreases
Successive waves bunch up
Deepest part of wave slows down more than top
The wave begins to steepen as the crest advances ahead of the base
When water is less than 1.3x wave height, the wave breaks
Swash
Movement of a wave up the beach.
Backwash
Wave drawn back down the beach.
Constructive waves
Low in height
Low frequency 6-8 per minute
Spilling
Strong swash
Long wavelength means backwash returns to sea before next wave breaks so swash uninterrupted and retains energy
Swash energy > backwash
Destructive waves
Greater height
Shorter wavelength
Higher frequency 12-14 per minute
Plunging waves
Little forward transfer of energy
Swash energy < backwash
High energy waves (winter) impact on beach
Remove material from top of beach
Transport it to offshore zone
Reducing beach gradient
Low energy waves (summer) impact on beach profile
Build up beach face
Steepen profile
Tides
periodic rise and fall of the sea surface, produced by the gravitational pull of the moon and the sun.
Tidal range
Significant in development of coastal landscapes
In enclosed seas e.g. Mediterranean tidal ranges are low somwave action restricted to narrow area of land
Tidal range influences where wave action occurs
More spread out over bigger tidal range
Spring tides
When the moon and the sun align, creating the highest tides.
Neap tides
When the moon and the sun are at right angles to each other, so the gravitational pull is at its weakest so tidal range in low.
Lithology
Physical and chemical composition of rocks.
Clay lithology
Weak
Bonds between particles are weak
Basalt
Strong lithology
Dense interlocking crystals
Highly resistant
Chalk and Carboniferous limestone
Predominantly composed of calcium carbonate
Soluble in weak acids
Vulnerable to carbonation
Structure
Properties of individual rock types e.g. jointing bedding and faulting
Primary permeability
Pores that can absorb and store water.
Secondary permeability
Joints or faults in rocks.
Concordant Coastline
single geology that runs parallel to coast.
Discordant Coastline
Rocks lie at right angle to the coast.
Strata
Angle of dip of rocks.
Rip currents
Currents caused by tidal motion or waves breaking at right angles to the shore
Cellular circulation generated by differing wave heights parallel to the shore
Water from top of breaking waves with a large height travels further up shore and returns where lower wave heights have broken
Modify shore profile by creating cusps which help perpetuate rip currents - channeling flow through a narrow neck
Warm Ocean Currents
Currents that move from the equator to the poles and influence western-facing coastal areas
Driven by onshore winds , greater effect on coastal landscape systems
Ocean currents
Generated by earths rotation and convection
Set in motion by movement of winds
Severn eastuary tidal range
14m
Sub-aerial processes
weathering and mass movement
Why are currents significant?
Transfer of heat energy directly affects sub-aerial processes
Terrestrial Sources
Sediment derived from the erosion of inland areas by water, wind and as as well as sub-aerial processes of weathering and mass movement.
Note 
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