Coastal Systems And Landscapes Defitions Flashcards
What is an emergent coast
A coastline that is advancing relative to the sea level at the time
What is a Dalmatian coast
CC SVVRP
A concordant coastline with several river valleys running perpendicularly to the coast
What is abrasion
A form of erosion where loose material ‘sandpapers’ the walls and floors of the river, cliff
What is backshore
The upper beach closest to the land, including any cliffs or sand dunes.
What is beach morphology
The surface shape of the beach.
What is Coastal Recession
The retreat of a coastline due to erosion,sea-level rise or submergence.
What is a concordant coast
- A coastline where bands of alternate geology run parallel to the coast.
What is corrasion
A form of erosion when breaking waves fling material (rocks, sediment, shells. etc) at a cliff face, physically knocking off material.
Discordant Coast
A coastline where bands of alternate geology run perpendicular to the shore.
What is Dynamic Equilibrium
- Where a natural system tries to achieve a balance by making constant
changes in response to a constantly changing system.
What is Eustatic
Eustatic - Global changes to sea levels.
What is the Fetch of a wave
The distance the wave travels before it reaches the coastline. Distance to the nearest land mass in the direction in which the wave travels
What is a Fjord
“valleys that get flooded by sea water”
Long narrow inlet deeper in the middle section than at the mouth, created when sea levels rise relative to the land, flooding coastal glacial valleys
What is freeze thaw weathering
Freeze Thaw - A form of physical sub-aerial weathering where water freezes in the cracks of a rock, expands and enlarges the crack, therefore weakens the rock.
What is the definition of geology
Geology - The structure and arrangement of a rock
What is a high-energy environment
High-energy Environment - A coast where wave action is predominantly large destructive waves, causing much erosion.
What is hydraulic action
Hydraulic Action - The pressure of compressed air forced into cracks in a rock face will cause the rock to weaken and break apart.
What is an integrated costal zone management (ICZM)
Integrated Coastal Zone Management (ICZM) - Large sections of coastline (often sediment cells) are managed with one integrated strategy and management occurs between different political boundaries.
What is impermeable
Impermeable - A rock that does not allow rainwater to pass through.
What is isostatic
Isostatic - A change in local coastline or land height relative to sea level.
What is a littoral cell
Littoral Cell - A section of the coast, within which involves much sediment movement. A littoral cell is not a closed system
What is longshore drift
Longshore Drift - The transportation of sediment along a beach. Longshore Drift is determined by the direction of the prevailing wind.
What is a low-energy environment
Low-energy Environment - A coast where wave action is predominantly small constructive waves, causing deposition and leading to beach accretion.
What is mass movement
Mass Movement - The falling or movement of rock, often due to Gravity.
What is permeable
Permeable - A rock that allows rainwater to pass through it.
What is a ria
Ria - Narrow winding inlet which is deepest at the mouth, formed when sea levels rise causing coastal valleys to flood.
What is saltation
Saltation - Smaller sediment bounces along the sea bed, being pushed by currents.The sediment is too heavy to be picked up by the flow of the water.
Sediment cell
Sediment Cell - Sections of the coast bordered by prominent headlands. Within these sections, the movement of sediment is almost contained and the flows of sediment should act in dynamic equilibrium.
What is a sediment budget
Sediment Budget - Use data of inputs, outputs, stores and transfers to assess the gains and losses of sediment within a sediment cell.
What are subaerial processes
Subaerial Processes - The combination of mass movement and weathering that affects the coastal land above sea.
What is a submergent coast
Submergent Coast - A coast that is sinking relative to the sea level of the time.
What is wave quarrying
Wave Quarrying - When** air is trapped and compressed against a cliff** which causes rock fragments to break off the cliff over time.
What are the 3 main inputs
Marine: Waves, Tides, Salt Spray
Atmosphere: Sun, Air Pressure, Wind Speed and Direction
Humans: Pollution, Recreation, Settlement, Defences
What are a few examples of outputs
Ocean currents
Rip tides
Sediment transfer
Evaporation
What are some examples of stores/sinks
Beaches
● Sand Dunes● Spits● Bars and Tombolos● Headlands and Bays● Nearshore Sediment● Cliffs● Wave-cut Notches● Wave-cut Platforms● Caves● Arches● Stacks● Stumps● Salt Marshes● Tidal Flats● Offshore Bands and Bars
What are some transfers/flows
Wind-blown sand
● Mass-movement processes
● Longshore drift
● Weathering
● Erosion
○ Hydraulic Action○ Corrosion○ Attrition○ Abrasion
● Transportation
○ Bedload○ In suspension○ Traction○ In solution● Deposition○ Gravity Settling○ Flocculation
What is negative feedback
When the system goes back to dynamic equilibrium
What is the negative feedback loop
Negative feedback loop - this lessens any change which has occured within the system.
What is the positive feedback loop
Positive feedback loop - this exaggerates the change making the system more unstable and taking it away from dynamic equilibrium:
What are the 6 examples of sediment sources
Rivers, cliff erosion, wind, glaciers, offshore, long shore drift
What is a sediment budget
They use data of inputs, outputs, stores and transfers to assess the gains and losses of sediment within a sediment cell.
What is the littoral zone
The littoral zone is the area of land between the cliff’s or dunes on the coast and the offshore area that is beyond the influence of the waves.
Why does the littoral zone change in the long and short term
Short-term factors like tides and storm surges
● Long-term factors like changes in sea level and human intervention
What is a constructive wave
Constructive waves tend to deposit material, which creates depositional landforms and increase the size of beaches. Strong swash, weak backwash
What is a destructive wave
Destructive waves act to remove depositional landforms through erosion, which work to decrease the size of a beach. Weak swash, strong backwash
How does negative feedback affect beaches and waves
Constructive waves causes deposition on the beach, which in turn leads to the beach profile becoming steeper.
Steeper beaches- formation of destructive waves. erode the beach, reducing the beach profile and leading to the formation of constructive waves.
How does the sun and moon affects tides
The highest high tide and the lowest low tides occur when the sun and the moon are in alignment. Both of their gravitational forces combine to effectively pull the oceans towards them to cause the highest high tides
What is longshore drift
Waves hit the beach at an angle determined by the direction of the prevailing wind
● The waves push sediment in this direction and up the beach in the swash
● The wave then carries sediment back down the beach in the backwash
● This moves sediment along the beach over time
Spit formation?\
(SPITS)
S- sediment carried by longshore dirft
P- projection into the sea ( the sediment builds outwards
I- Isolated areas behind (sheltered water, salt marhses can form
T- turn (spit may curve due to changes in the wind or wave direction
S- Stabilised (vegetion might grow)
Bar formation (Bars)
B- build up of sediment across a bay
A- Across (joins two headlands)
R-Results in a lagoon behind
S-seals off the bay
