WAVES Flashcards
what 2 forces cause waves to form
- Disturbing force e.g. gravity, wind, seismic activity
- Restoring force e.g. cohesion of water molecules, gravity
what causes ocean waves
Air – ocean interface
what causes internal waves
Ocean – ocean interface
what are Progressive waves and its 3 types
waves that oscillate uniformly and progress without breaking
1. Longitudinal
2. Transverse
3. Orbital
Orbital Wave Characteristics
- Diameter decreases with depth
- Wave base = ½ L
- Hardly any motion below wave base
what is stokes drift
Small net transport of water in the direction of wave movement
what are deep water wave characteristics
- Wave base = L/2
- hardly any motion below wave base
- Lack of orbital motion at depth - useful for
floating runways and other structures
**If water depth (d) > L/2, wave is a deep water wave
how to calculate Wave speed (C)
wavelength (L) / period (T)
Shallow–Water Waves characteristics
- Water depth (d) < L/20
- Wave “feels” seafloor
what type of waves are Wind–Generated
- Capillary waves – wind generates stress on sea surface
- Gravity waves – increasing wave energy
3 Factors Affecting Wave Energy
- Wind speed
- Wind duration
- Fetch – distance over which wind blows
what determines wave height
Directly related to wave energy (product of wind speed, wind duration, and fetch)
how are Wave Interference Patterns formed and its 2 types
Collision of two or more waves
- Destructive interference – canceling effect
- Constructive interference – additive
tsunami characteristics
long-wavelength, progressive waves
* Caused by rapid displacement of water
* Always shallow-water waves
* Move quickly
* Very destructive on land
5 wave types
capillary
wind wave
seiche
seismic (tsunami)
tide
