Distinctive features of the coastal zone Flashcards
(20 cards)
What is the littoral zone?
The coastal zone in which sediments are moved around between the land, beach and sea
Why is the littoral zone dynamic (always changing)?
These changes are due to the interactions between the processed happening on land, in the seas and in the oceans. It varies because of
- short term factors (individual waves, daily tides, seasonal storms)
- long term factors (sea level changes and climate change)
What are the 4 divisions of the littoral zone?
Backshore
Foreshore
Nearshore
Offshore
What is the coastal system?
The coastal system helps us to understand the processes and interactions involved - the inputs, processes and outputs. In theory these work together to create coastal equilibrium
What are the 4 types of inputs?
Marine (tsunamis, waves, tides)
Atmosphere (precipitation, solar energy, wind)
Terrestrial (tectonics, geology)
Human (buildings, pollution, tourism, sea defences)
What are the 3 types of processes?
Deposition
Transportation
Erosion
What are some examples of outputs?
Spits
Beaches
Caves
Stacks
Arches
Headlands and bays
Cliffs
Sand dunes
Wave cut platforms
Define Store/component
A part of the system where energy is stored/transferred
Define system
A set of components working together
Define flow/transfer/flux
A form of transfer between one store and another
Define input
The addition of matter or energy into a system
Define a closed system
Does not interact with its surroundings
Define an open system
Interacts with its surroundings
Define the coastline
Part of the land near the sea; the edge of the land
Define the coast
Regarded as an open system with inputs, processes and outputs; interacts with its surroundings
What is the sediment budget?
The sediment budget is knowing exactly how much sediment is coming in along the coastline (input) and how much sediment is going out (output)
What are the 3 principal sources of beach sediment?
Rivers
Cliffs
Sand dunes
What are examples of outputs to the sediment budget?
Outputs to the sediment budget could include longshore drift, natural loss, aeolian (natural wind) loss and anthropogenic (human induced) losses
Features of a high energy (rocky) coastline
- The rate of erosion exceeds the rate of deposition
- Landforms include headlands, cliffs and wave cut platforms
- High levels of erosion, high wave activity, exposure to prevailing winds, a long fetch
- Example: Conachair in the outer Hebrides is a 426m granite coast
Features of a low energy (sandy/estuarine) coastline
- High levels of deposition, they are sheltered, and characterised by low wave activity
- The rate of deposition exceeds the rate of erosion
- Landforms here include beaches and spits
- Low-lying, low relief, contains wetlands and marshes, poor drainage, flat landscapes, just above sea level
- Coastal accretion can occur (where the coastline gradually moves seaward)