Coasts Flashcards
Describe the effects of slumping (3)
Loss of property (1)
Damage to farm buildings (1)
Potential loss of earnings (1)
Loss of land (1)
Explain the factors affecting the rate of coastal recession (4)
Softer geology increases rates of
coastal recession (1) due to lower resistance to
erosional impact of waves (1)
Increased fetch increases recession (1) due to more distance for greater build-up of wave energy (1)
Explain how coastal flooding can be reduced through planning and forecasting (4)
Planning:
Not allowing homes to be built in potential
flood-risk zones
Government planning laws
Forecasting: Improved forecasting (broadcasts) enables prediction of conditions at sea, therefore give warning of possibility of coastal flooding and allow measures to be taken to act against the risk of flooding
Environmental Agency.
Explain how an area of coastline has been managed (6)
Named example
Management techniques include groynes; rip-rap; sea walls etc
Clear explanation of points
Range of specific facts and explained points about how the
coast has been managed.
Suggest how wave fetch can cause different rates of coastal recession (2)
Increased fetch causes greater potential for
erosion (1), as wind can build bigger waves over a larger stretch of water (1).
Compare the characteristics of constructive and destructive waves (4)
Destructive waves have a greater backwash than swash (1) compared to constructive waves due to their higher energy (1) meaning that they can erode beaches (1)
Constructive waves have a lower frequency (1) as a result of their longer wavelength (1)
Destructive waves are plunging whereas
constructive are surging (1)
Destructive waves are higher (>1m) compared with constructive (1).
Outline the process of slumping (2)
Rotational movement of land at the coast (1), triggered by saturation (1)
State one impact of slumping on the coast (1)
Loss of land (1)
Destruction of property/infrastructure (1)
Loss of animal habitats (1)
Causes coastal recession (1)
Explain the formation of a spit. Use a diagram in your answer (4)
Movement of material along a coastline due to longshore drift
Occurs where there is a change in direction of the
coastline
Over time build up of spit as more sediment is deposited offshore
May curve at end due to action of wind/waves.
Formation of salt marsh due to spit protecting area from wave action.
Explain how the effects of coastal flooding are reduced. Use examples in your answer (6)
Flood walls along rivers
Flood barriers
Open space on flood plains to absorb water
Environment Agency monitors sea conditions
Describe the formation of a bar.
You may use a diagram to help with your answer (3)
- Bars form due to longshore drift often at bays
or inlets (1). - The spit extends across the bay until it reaches the other side (1).
- Sediment is moved by the action of swash and
backwash (1). - If a spit extends from one side of the bay to
the other it will form a bar (1). - A lagoon can form behind the bar once the bar
covers the bay (1)
Describe the differences between constructive and destructive waves.
You may use a diagram to help with your answer (4)
- Constructive waves = backwash > swash (1)
- Destructive waves have higher energy than constructive waves (1)
- Destructive waves remove sediment, whereas constructive adds it (1)
- Destructive waves break more often
- Destructive waves = higher than 1m, constructive below 1m (1)
- Stormy vs calm conditions (1)
Explain how geology influences the formation of coastal landforms (6)
- Headlands and Bays: hard rock -> formation of headlands as eroded at slower rate, as more resistant. Bays are formed of softer material therefore they erode at a faster rate.
- Caves and Arches – cracks and joints in the cliff face are exploited and become larger due to erosion. As result they widen to form caves. If two caves join,
they will form arches. - Stacks and stumps: erosion of the joints or
weaknesses at the base of the stacks leading to the collapse.
Suggest how the rapid recession of the coastline has an impact on both people and the environment (4)
Impact of erosion on people:
- loss of land
- loss of waste disposal site
- loss of water source
- loss of barge landing
- loss of school
- forced evacuation.
Impact of erosion on the environment:
- contaminated water source with salt water
- rapid recession of the coastline
- possible pollution of environment (if polluted by ‘dump site materials’)
- loss of water sources.
Outline the processes of weathering and mass movement on the coast (4)
Weathering:
- Weathering is the breakdown of material in situ (1)
- Occurs due to changes in the weather causing the rocks to be broken down over time (1).
- Freeze thaw occurs when there are diurnal changes in
the weather above and below zero degrees (1) -> rock joints to expand and break off (1) - Exfoliation occurs when there is a warming and cooling of temperature (1). This causes the rock to peel off in layers (1).
- Salt crystallisation is when salt gets into the cracks in rocks (1). It expands putting pressure on rock joints (1).
Process of mass movement:
- Mass movement is the downward movement of geological material on the coastal cliffs or slopes (1) caused by lubricated soil or gravity (1).
- Slumping =(rapid) downward movement of coastal cliffs (1) as a result of water lubricates a joint/weakness (1).
- Rock fall = (rapid) the collapse of material (1) due to gravity at the base of the cliff forming an overhang (1).
