Download Ocean Movements

Do Now – In Notebooks
1.
What is salinity?
2. What are the two possible ways the ocean became
salinated?
3. Explain one of the desalination processes.
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
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.
Wave Characteristics
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.
Wave Height
 Depends on three
factors:
 Wind Speed
 Wind Duration
 Fetch

Expanse of water wind
blows across
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
Wave Breaking
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
Upwelling
 Upwelling is the upward motion of ocean water
 Water is cold because it originates from the bottom