• moving energy
• most waves are wind-driven

• wind main disturbing force
• boundary between and within fluids with different densities
• air/ocean interface: ex. ocean waves
• air/air interface: ex. atmospheric waves

• splash wave
• coastal landslides, calving icebergs (when chunk of icebergs fall off into ocean)
• seismic sea wave of tsunami (sea floor movement)
• wake (ex. ships)
• tides (gravitational attraction among moon, sun, and earth)

• F= 1/T
• number of waves passing a fixed location per unit time (it is the inverse of period)

move in a wave...only the waveform

large majority of water is not moving, it's the energy that's moving

• waves transmit energy
• cyclic motion of particles in ocean
• particles may move
• up and down
• back and forth
• around and around
• particles in ocean waves move in orbital paths

• push-pull waves
• particles move back and forth in direction of energy transmission
• energy transmitted by compression and decompression
• energy transmitted through solid, liquid, gas

• side-to-side waves
• particles move at right angles to direction of energy transmission
• energy transmitted by vibration

• particles move in orbital path (both longitudinal and transverse)
• energy transmitted along interface between two fluids of different density

• equal to one half of the wavelength (at SWL) or L/2

• the rate at which the wave travels
• S= wavelength(L) / period(T)
• more correctly known as CELERITY- used only in relation to waves where no mass is in motion, just the wave form

• exist in water that's deeper than their wave base
• move at speeds controlled by wavelength
• water depth is greater than wave base  (≥ ½ L)
• includes all wind generated waves
  

• exist in water shallower than 1/20 their wavelength
• move at speeds controlled by water depth
• aka long wave
• water depth is ≤ 1/20 L
• deeper the water- the shallower the waves move
• ex. tsunami, tides, and wind-generated waves that move into shallow nearshore areas

• are in between
• characteristics of both deep and shallow-water waves
• 1/20 wavelength  ≤ depth ≤ ½ wavelength

slow wave + undulating wave= mixed wave

unpredictable patterns, hard to sail in

• 1 in 23 waves will be 2x as high
• 1 in 1175 will be 3x as high
• 1 in 300,000 will be 4x as high
• truly big---1 in several billion

1. "walls of water" traveling up to 10km (6.2mi) through the ocean

2. "three sisters" groups of three waves

3. single, giant storm waves, building up to fourfold the storm's waves height and collapsing after some seconds

• reliable measurement
• wave height 34 m or 112 ft

• uniform, symmetrical waves that travel outward from storm area
• long crests
• transport energy long distances
• Longer wavelength waves travel faster and outdistance other waves
• Wave train = group of waves with similar characteristics
• Sorting of waves by their wavelengths is wave dispersion
• Wave train speed is ½ speed of individual wave

Generally – ground swell is  larger and from farther away; wind swell is smaller locally-produced wages.

• water slides down front slope of wave
• gently sloping sea floor
• wave energy expended over longer distance

• curling crest
• moderately steep sea floor
• wave energy expended over shorter distance
• best for board surfers

• breakers on shore
• steepest sea floor
• energy spread over shortest distance
• best for body surfing

• Pacific waves are bigger
• Steeper beach slopes -->  plunging breakers –
• Wind blows toward shore (east coast  - wind typically blows away from shore)

• most occur in pacific ocean (more earthquakes and volcanic eruptions)
• damaging to coastal areas
• loss of human lives
• example, Krakatau eruption (1883) in Indonesia created tsunami that killed more than 36,000 people
• example, Aura, Japan (1703) tsunami killed 100,000 people

30 meters (98ft)

Tsunamis may reach a maximum vertical height onshore above sea level

• as waves approach shore, they bend so wave crests are nearly parallel to shore
• wave speed proportional to depth of water (shallow-water wave)
• different segments of wave crest travel at different speeds

• energy focused on headland
• headland eroded
• energy dissipated in bay
• bay filled up with sediment

• waves and wave energy bounced back from barrier
• reflected wave can interfere with next incoming wave