1. WAVES disturbance caused by the movement of energy from a source through some medium (solid, liquid or gas).

2. WAVES The energy is moving at the speed of the wave, but NOT the water

5. WAVES The parcel of water moves in a circular motion = orbit

6. Fig. 9-3, p. 201

7. WAVES Because the wave form moves forward these are called progressive waves

8. Fig. 9-2, p. 201

9. Orbits The diameter of the orbits diminishes rapidly with depth Wave motion in deep water is negligible past ½ the wavelength

11. Stoke’s Drift or Mass Transport Small net movement of water in the direction of the wave

13. Classifying Waves disturbing force = the energy that cause waves to form restoring force = the dominant force trying to return surface water to flatness wavelength

14. Table 9-1, p. 202

15. Figure 8.9

16. Deep vs Shallow Water waves The orbits of water molecules in a wave are circular only when the wave is in deep water A wave cannot “feel” the bottom if it is in water deeper than ½ its wavelength = a deep water wave

17. Figure 8.7a: Deep Water Wave

18. Figure 8.7b Transitional waves = travel through water deeper than 1/20 their wavelength and shallower than ½ its wavelength

19. Figure 8.7c Shallow water waves = moving in water shallower than 1/20 it wavelength Water at the bottom moves back and forth

20. Deep vs Shallow Water Waves ONLY WIND WAVES CAN BE DEEP WATER WAVES

22. How waves break at shore... A deep water waves feels bottom and becomes a transitional wave then a shallow water wave orbits become elliptical crests become peaked so wave height increases Waves in front slow down so wave length decrease

23. How waves break at shore... The wave becomes too high for its wavelength and the wave breaks –Wave steepness is waveheight/wavelength –When H/L = 1/7, the wave breaks The surf zone is the region between the breaking waves and the shore.

24. How large do wind waves get? Depends on –wind strength –wind duration –fetch (distance over which wind blows) Waves spread out (dispersion) based on size (large waves move faster) –Capillary waves … wind waves…fully developed seas…swell

25. Figure 8.10

26. Fig. 9-9, p. 207

27. Fig. 8.12 Highest wave: 1933 – in Pacific during a strong storm: strong wind in one direction for days…112ft (34 m)

28. INTERFERENCE Destructive interference = cancellation effects of subtraction –When a wave crest and another wave’s trough coincide

29. INTERFERENCE Constructive interference = addition effects that form large crests and deep troughs –When crests coincide

30. Figure 8.15

31. Figure 8.16

32. Fig. 9-13 (a-b), p. 209

33. Fig. 9-13c, p. 209 Constructive Interference can cause “Rogue Waves”

34. Fig. 9-16, p. 211 A 20 m (66 ft) wave in Hawaii

35. Wave Refraction When waves do not approach parallel to shore… The wave line will bend to become more parallel to shore

36. Figure 8.19a

37. Figure 8.19b

38. Figure 8.19c