1. Chapter III
Waves and Tides

2. Wave Parts Waves are driven by wind Crest Trough
Size = wave height = vertical distance between trough and crest
Distance between waves (wavelength) = period = time it takes the wave to go by a point

3. Wave Movement Water particles don’t have any net movement
Crest move up and forward
Trough move down and back
Carries energy

4. Formation of Waves Wind forms waves
Fetch = span of open water over which the wind blows
Swells form in open ocean
Cancellation = crest and trough meet and average out
Reinforcement = crest and crest meet and produce a bigger wave

5. Breaking Waves In shallow water waves: Slow down Get higher
Get closer together
Break when get too steep and unstable

6. Tides
Tides = rhythmic rising and falling of water caused by the gravitational pull of the sun and moon
Moon has a stronger pull because it is closer

7. Gravitational Pull Moon pulls water towards it
Bulge on that side of earth
Bulge on opposite side of earth because of centrifugal force
Earth rotates under the bulge to get high and low tides
Sun does the same thing, but weaker
Can have additive impacts

8. Timing of the tides 2 high tides, 2 low tides every 24 hrs and 50 min
50 min accounts for the moon’s movement

9. Tidal Range = difference in water level between successive high and low tides
Spring tide = large (sun and moon in line)
Neap tide = small (sun and moon at odds)
Tidal Range

10. Tide Types Number of tides
Semidiurnal tides = 2 high, 2 low (N. America, Europe, Africa)
Mixed semidiurnal tides = 2 high, 2 low but of different ranges (West coast of N. America)
Diurnal tides = 1 high, 1 low (Antarctica, Caribbean, Canada

11. Tide Types

12. Tide Tables
freetidetables.com