Ocean Waves and Tides

1. Ocean Waves and Tides

2. Waves • Ocean waves can form from something as simple as wind or as violent as an earthquake • They can travel through water slowly or incredibly quickly

3. Anatomy of a Wave • Waves are made of two main parts • Crests: highest point of the wave • Troughs: lowest point of the wave

5. Anatomy of a Wave • The distance between two adjacent wave crests or wave troughs is a wavelength • The vertical distance between a crest and trough is the wave height

6. Wave Energy • When a wave occurs, energy from the wind moves through the water • The water particles do not move, only the energy

8. Wave Speeds • Scientists need to know the wavelength and wave period to calculate wave speed • Wave period is the time between the passage of two crests/troughs

9. Wave Speed Equation • Wavelength (m) = speed Wave period (s)

10. Types of Waves • Shore currents create an undertow which brings water back into the ocean • Longshore currents cause waves to hit the shore at an angle

12. Types of Waves • Whitecaps form in the open ocean due to heavy winds, storms • Swells also form in the open ocean, but are much longer than whitecaps

14. Types of Waves • Tsunamis are large waves that are formed from violent activity on the ocean floor (earthquakes, landslides)

16. Tides • The rise and fall in sea level is called tide. • A tide is caused by a giant wave produced by the gravitational pull of the Sun, Earth and Moon

17. Tides • The tidal range is the difference between the level of the ocean at high tide and low tide.

19. Tides • The Moon’s gravity exerts a strong pull on Earth. • The water bulges outward as Earth and the Moon revolve around a common center of mass.

20. Tides • The ocean bulges are the high tides, and the areas of Earth’s oceans that are not toward or away from the Moon are the low tides.

22. Spring Tides • When the Moon, Earth, and the Sun are lined up together, they cause spring tides. • During spring tides, high tides are higher and low tides are lower than normal.

24. Neap Tides • Neap Tides are when the Sun, Earth, and the Moon form a right angle, • High tides are lower and low tides are higher than normal.

26. Question 1 • What are two ways waves can form?

27. Answer • Ocean waves can form from something as simple as wind or as violent as an earthquake

28. Question 2 • What are the four parts of the anatomy of a wave?

29. Answer • Crest, Trough, Wavelength, Wave height

30. Question 3 • What force causes the formation of high tides and low tides?

31. Answer • The gravitational pull between the earth and moon cause the tides