Coasts 2 Flashcards
What are the coastal hazards?
- tsunami
- subsidence
sea level rise
erosion }shoreline change
algal bloom
hypoxia and eutrophication
fishing industry, trawling
Are coasts extremely dynamic?
YES!!!
What are ocean waves a function of?
wind speed, time, and fetch
What kind of motion do deep water waves have?
circular
What base depth is what in relation to wavelength?
1/2 of wavelength
What is the wave base for deep water waves(typically)?
300m
Discuss shallow water?
- the depth is less than the wave base
- waves slow down in shallow water
Where does the breaker zone occur for shallow waves?
1/2 of wavelength
Shoreline Features: Erosional Features
- wave-cut cliffs
- wave-cut platforms
- arches
- stacks
Discuss wave refraction?
- waves are refracted or bent as they approach the beach in an oblique direction
- wave refraction causes wave energy to be focused on headlands
Refraction
is the change in direction of a wave due to a change in its velocity
Where does refraction focus energy?
-headlands
Depositional Features
- barrier islands
- tidal deltas
- spits
- tombolo
Where do long shore currents occur?
-breaker zone and beach
How do long shore waves flow in relation to the beach?
parallel to the beach?
