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What’s current with the ocean?. Catch my drift?. Currents move water from place to place. There are 2 kinds of currents…. First kind of current:. Surface currents : move on or near surface of ocean Friction between wind blown air and the water surface causes the water to move - PowerPoint PPT Presentation
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What’s current with the ocean?
Catch my drift?
Currents move water from place to place
There are 2 kinds of currents…
First kind of current:1.Surface currents: move
on or near surface of ocean• Friction between wind blown
air and the water surface causes the water to move
• Controlled by wind belts, earth’s rotational effect and location of continents
What direction do most currents NORTH of the equator move?
CLOCKWISE!
What direction do most currents SOUTH of the equator move?
COUNTERCLOCKWISE!
• Western side of ocean has warm currents traveling from equator
• Eastern side of ocean has cool currents moving toward equator
Examples of warm water currents:• Gulf Stream• Brazil
Examples of cold water currents:• California current• Canary current
Upwelling• the rise of cold water from deeper layers to replace warmer surface water.
• brings greater concentrations of dissolved nutrients, such as nitrates and phosphates, to the ocean surface.
Second kind of current:
2. Deep density currents: cold, dense currents that flow very slowly beneath surface of ocean• occurs when denser
seawater moves towards an area of less dense seawater
• In the deep ocean, denser water around the Poles sinks and travels along the ocean floor toward the equator.
• At the same time, less dense water at the equator rises and moves towards the poles along the surface.
• These two events form a continuous cycle that circulate ocean water.
Waves
Kelly Slater
Wave Generating forces• WIND• TIDES• Sometimes Earthquakes
Wavelength•Distance from one crest to another
Wave Height•Difference between crest to trough
Period:•The time it takes one wavelength to pass a given point
Formula
Speed= wavelength period
Test your knowledge…
What is the speed of a wave 24 meters long with a period of 4 seconds?
Applying the formula
Speed = 24 meters= 6 meters/sec 4 sec
Height of wind-formed waves depends on 3 things…
1. Length of time the wind blows2. Speed of wind3. FETCH: length of open water
over which the wind blows in a single direction
Swells• Group of long, rolling waves all
about the same size• Come at regular intervals
• As waves approach shore, the water is so shallow that they touch bottom. This happens at a depth of one-half the wavelength. As the wave scrapes bottom, the lower part of wave slows down and upper par moves ahead. The crest falls over and breaks onto the beach.
Breaking Waves
MAVERICKS
Waves and the shore:• Breakers – foamy mass of water that
washes onto shore• Undertow• Long shore current• Tsunamis• Rip current – strong surface currents
that flow away from the beach; hazard to swimmers