✅3.1.3.2 - Systems and Processes Flashcards
What are some of the sources of energy in the coastal system?
Wind
Waves
Currents
Tides
How does the wind provide energy?
Strong winds move the water surface and create waves
Winds with large fetches can transfer more energy
How do waves provide energy?
Waves have powerful errosive energy, can destroy features
Moves sediment around, creates as well as destroys
How do currents provide energy?
Can move sediment on the sea floor
More material on and off coastline regularly, great force
How do tides provide energy?
Moves sediment up the beach and down again, carries material
Dictates where waves can get to, location of the energy
How does the sun provide energy?
It causes differences in air pressure due to different rates of heating, when then creates wind
How is wind energy formed?
By air moving between areas of different pressure
How are powerful winds created?
The greater the difference in air pressure gradient, the faster the wind speed and the more powerful
What are the factors impacting the size of waves?
Strength of the wind
The fetch
Duration of the wind
How does wind strength impact waves?
The stronger the wind, the more power and energy the waves have and so the more powerful and potentially destructive they are.
What are some terrestrial features affecting the coastal system?
Tectonics
Sediment supply
Sub aerial processes
Fluvial processes
What are some marine features affecting the coastal system?
Wave shape/size Fetch Wave direction Tides Sea level change
What are some human features affecting the coastal system?
Development Sea defences Tourism and recreation Pollution Global Warming Conservation
What are some atmospheric features affecting the coastal system?
Winds Temperature Precipitation Solar energy Glaciation
How are waves formed?
By energy passing through the water, causing it to move in a circular motion
What do waves transmit?
Energy, not water
What are wind driven waves caused by?
Frictional drag between the wind and the surface water
How do waves change as they approach the shore?
Disturbance to the circular motion beneath the surface leads to a more horizontal movement and the wave breaks
What are the features of constructive waves?
Add material to coastline
Low wave with long wavelength
Strong swash
What are the features of destructive waves?
Tall in relation to length Remove material from coastline Common in winter Strong backwash Never reach the backshore Causes cliff face erosion
What are orthogonals?
Lines of wave energy
What are high energy coastlines like?
Rocky, ocean facing coasts where waves are powerful
What types of landforms tend to be on high energy coasts?
Wave cut platforms and headlands
What are low energy coastlines like?
Sandy, estuarine and where waves are less powerful as the coast is sheltered
How do rates of deposition and erosion compare at high energy stretches of coast?
Rate of erosion exceeds rate of deposition