COASTS Flashcards
What is a model?
A way of understanding a complex world in simple form.
What are the four factors every model has.
1) Inputs
2) transfers
3) outputs
4) boundaries
What is the input?
Anything added to the model
What is the transfer?
Processes within a model
what is the outputs?
Anything leaving the model.
What are the boundaries?
The outer area of a model.
What is an open system?
Has inputs and outputs.
What is a closed system?
Doesn’t have inputs or outputs
What is energy in terms of natural systems?
Driving force/ power
What are stores and components in terms of natural systems?
The individual elements which make up a system.
What is positive feedback?
The flow/ transfer which results in increase/growth. creating change in balance of system = new equilibrium
What is negative feedback
Where flow/transfer result in decrease/ decline. to restore the balance of the system = dynamic equilibrium
Dynamic equilibrium
Represents the state of balance within a changing system.
how does wind travel?
diffuses from areas of high pressure to areas of low pressure
factors which increase wind strength
^duration, ^extent of pressure gradient, ^fetch
how are waves formed? (6 steps)
1) wind over water = frictional drag.
2) circular motion of water
3) shallower water = friction at sea floor
4 )elliptical movement
5) WL and velocity decrease and height increases
6) water backs up and rises to breaking point
formation C+D
near weather system = D
far weather system = C
wave form C+D
low surging wave, long wavelength C
short walelength, high plunging wave = D
beach profile C+D
steep, but flatten over time with erosion LOSS= D
gentle incline, but becomes steeper w deposition GAIN=C
neeptide
lowest tidal range
spring tide
highest tidal range
rip current
strong localised underwater current when plunging waves are met with breaking waves causing currents to form between.
tides
change in water level due to position of sun and moon.
wave refraction
energy concentrates around headlands and dissipates in bays - erosional and depositional land forms
sediment cells
stretch of coastline that is a relatively closed system usually bordered by 2 headlands. eg Christchurch bay
no. sediment cells in england and whales
11
sub cells
link marine processes
sediment budget
losses and gains of materials and energy
weathering
breaking down of rocks in situ, not due to sea, leads to transfers of materials
mechanical weathering (4)
exfoliation (temp) , freeze thaw, crystallisation (salt crystals), wetting & drying
coastal marine processes
erosion, deposition, transpotration
sub-areal proccesses
weathering, mass movement and run off
chemical weathering
carbonation (acid rain calcium carbonate to calcium bicarbonate )
oxidisation (rusting)
biological weathering
plants, animals
slumping
stages, rotational slip, saturation and undercutting
soil creep
gradual movement of individual particle, wet dry, g
rock fall
rapid free fall, steep slope , dry conditions, freeze thaw
landslides
sections of cliff detached, saturation
mud flow
steep slopes, saturated clay, little vegetation