Presentation on theme: "Ocean Waves Essential Question How does ocean water work? Objectives Identify parts of a wave Explain the process that causes waves to break Describe."— Presentation transcript:
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.
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
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