Ocean Movements

1
Ocean Movements
2
Ocean Waves

• Essential Question
• How does ocean water work?
• Objectives
• Identify parts of a wave
• Explain the process that causes waves to break
• Describe different ocean currents

3
Waves

• A wave is a rhythmic movement that carries energy
  through matter or space.
• As a wave passes, only energy moves forward,
  while the water molecules move around in circles
  and stay near their original position.
• Waves are created by friction from wind.

4
Wave Characteristics
5
Wave Characteristics

• The crest is the high point of a wave.
• The trough is the low point of a wave.
• Wavelength is the horizontal distance between the
  crests or between the troughs of two waves.
• Wave height is the vertical distance between
  crest and trough.
• Half the distance of the wave height is called
  the amplitude of a wave.

6
Wave Height

• Depends on three factors
• Wind Speed
• Wind Duration
• Fetch
• Expanse of water wind blows across

7
Breakers

• Waves lose energy and slow down as they reach the
  shore, due to friction with the beach
• Incoming crests catch up to slower crests ahead
• smaller crest-crest wavelength
• Waves become higher, steeper, and unstable
• The crests collapse forward

8
Wave Breaking
9
Ocean Currents

• Density Current
• Due to difference in temp. and salinity
• Move slowly in deep ocean waters
• Surface Current
• Wind-driven
• West to east due to prevailing westerlies

10
Upwelling

• Upwelling is the upward motion of ocean water
• Water is cold because it originates from the
  bottom