Sources of energy at the coast Flashcards
What is the primary source of energy in the system
The sun
What is the main form on energy on a coast
Waves
How are waves created
Tectonic activity and wind
Where does wind move from
High pressure to low pressure
Factors that affect wave energy
- strength of the wind
- duration of the wind
- fetch (distance of open water)
Features of constructive waves
- low surging waves, long wavelength
- strong swash, weak backwash
- beach gain
Features of destructive waves
- high lunging waves, short wavelength
- weak swash, strong backwash
- beach loss
What’s the difference between neap and spring tides
Neap tides have small tidal range and spring tides have large tidal range
What is the impact of tides
They determine the height and duration of waves
Features of a high energy coastline
- rocky coasts
- erosional landforms (headlands, cliffs, wave cut platforms)
- erosion rates exceed deposition rates
Features of a low energy coastline
- sandy and estuarine coasts
- depositional landforms (beaches, spits)
- deposition rates exceed erosion rates
What is wave refraction
Causes energy to be concentrated at headlands and dissipated in bays
What is an example of negative feedback with wave refraction
Variations in rock strength leads to the formation of headlands and bays - this causes wave refraction - leads to the erosion of headlands and bays
