1. Waves, Tides and Currents

2. I. The Ocean’s Motions The ocean never rests. Currents, waves, and
tides all move and mix
the ocean waters.

3. II. Surface Circulation
A. Currents and
waves are
driven by wind.
B. Wind is driven
by heat from
the sun.

4. III. Coriolis Effect A force resulting from the rotation of the earth.
It mainly affects freely moving objects, making it impossible to move in a straight line.

5. Organisms do not notice the coriolis effect because it is too slight.
D. Winds and currents are strongly influenced
by the Coriolis
Effect.

6. E. Earth’s rotation causes motion of objects to be deflected to the
right or left.
1. Northern Hemisphere-
movement deflected
to the right.
2. In Southern
Hemisphere –
to the left.

7. IV. Winds A. Most solar energy is absorbed at the equator.
B. As warm air rises, cooler air moves in replacing the warm air thus creating wind.
C. Wind moves in bent lines due to the coriolis effect.

8. D. Trade Winds
1. Easterly surface winds found in the tropics near the equator.
2. Northern Hemisphere they blow northeast.
3. Southern Hemisphere - they blow southeast.
4. Approach the equator at 45⁰.

9. The Trade Winds

10. V. Currents A. Areas of water flowing naturally in the ocean driven by
the wind, salinity and the surface temperatures.
B. The currents move off at a 45° angle due to the Coriolis Effect.

11. C. Surface currents are caused by the
wind blowing across the water
surface.
D. When pushed by the winds, the
currents do not
move the same
direction as the
wind.

12. VI. Gyres Definition – huge rotating currents of water in the ocean.
Gyres develop due to the influence of the coriolis effect.
There are 5 major gyres.

13. North Equatorial Current – California Current
North Equatorial Current – Canary Current
South Equatorial Current-West Australian Current
South Equatorial Current – Peru Current
South Equatorial Current – Benguela Current

14. Smaller Gyres

15. D. Pollution-gyres collect ocean trash, solutions are needed.

16. Show Video Clip – Safari Montage (Ocean Currents)

17. VII. Waves A. Most familiar ocean phenomena. B. Wave Anatomy
1. Crest-high point
2. Trough-low point
3. Wavelength-distance from one
crest to another
4. Amplitude– rise and fall

18. C. Wave Anatomy

19. D. Water Movement 2. Water under the troughs move down and backwards.
1. Water under the crests move up and forward.
2. Water under the troughs move down and backwards.
3. Water is actually just rolling in place or circling around and not really going anywhere.

21. VIII. Tides
A. Definition - The rhythmic rise and fall of sea levels. B. Caused by the gravitational pull of the moon and the sun, along with the rotations of the earth, moon, and sun.

22. C. Centrifugal Force in Tides
1. Definition – outward force from the center of a rotation on a body rotating around another body.
2. The moon does not rotate around the earth rather both rotate around the center of their combined mass.

23. 3. On the side where the moon
pulls strongly on earth, it pulls on the oceans’ surface water too.
4. On the opposite side centrifugal force pushes water away from the earth.

24. Low Tide verses High Tide

25. High Tide verses Low Tide

26. D. The Sun’s Impact 1. The sun is much larger and
is 400 times farther away
from the earth than the moon.
2. Gravitational pull of the sun is
half that of the moon.

27. E. Moon Phases -
Moon phases determine ocean tides.

28. F. Types of Tides
Spring Tides - When the sun and moon are in line with each other.
a. Sun and moon’s combined pull affects the tide
b. Occurs at new and full moons.
c. There is a large difference between high and low tide.

29. d. Spring Tide Alignment

30. 2. Neap Tide - When the sun and. moon are at right angles with
2. Neap Tide - When the sun and moon are at right angles with each other
a. Effects of sun and moon are both diminished
b. Occurs at first and third quarter.
c. There is a small difference between high and low tide.

31. d. Neap Tide Alignment

32. G. Effects of Tides 1. Tides influence life of near shore organisms.
a. Alternately expose and submerge organisms
b. Determines circulations of bays
c. Triggers spawning.

33. Comparison of Tides