1. Physics of surfing

2. videos Science of Big Waves (KQED) Garrett McNamara w/ GoPro, 90’+
Teahupoo raw 2013

3. The energy of a wave travels ahead but the water itself does not

4. Why are there consistently bigger waves in the Pacific?

5. Factors determining wave power: wind v, wind duration, and fetch

6. Why are the conditions so different?

7. Ground swell vs. wind swell

10. Seafloor determines wave (shape)

11. Wave energy consolidates due to DIFFRACTION

14. To what depth would a seasick scuba diver have to go for relief?

16. Breakers form
In roughly ½ of the wavelength. So if there is a longer period, you have bigger waves.

17. What is shown here?

18. So what are ideal surf conditions?

19. So what are ideal surf conditions?
Wind: off-shore, not too strong

20. So what are ideal surf conditions?
Wind: off-shore, not too strong
Period: long (ground swell)

21. So what are ideal surf conditions?
Wind: off-shore, not too strong
Period: long (ground swell)
Tide: dependent on particular break location

22. So what are ideal surf conditions?
Wind: off-shore, not too strong
Period: long (ground swell)
Tide: dependent on particular break location
Substrate: sudden rise, reef, often a point

23. how heavy is a big wave?

24. > 1 ton per 1 m3

25. Forces in balance while riding

26. Useful sites
Magic Seaweed
Surf-forecast.com

27. Other types of waves

29. CAPILLARY WAVES

30. A seiche is a standing wave in an enclosed or partially enclosed body of water.
Seiches have been observed on lakes, reservoirs, swimming pools, bays, harbors and seas.

32. A tsunami (at one time incorrectly referred to as a tidal wave), is a series of water waves caused by the displacement of a large volume of a body of water, usually an ocean.
Created by: Earthquakes, volcanic eruptions and other underwater explosions, landslides glacier calvings and meteorite ocean impacts

34. 2004 Indian Ocean Tsunami - Indonesia -
35 meters high on shore - 176,000 fatalities
Diffracted around world, even to RI

35. Tsunami videos Japan 2011-raw: video Japan 2011: National Geographic
Tsunami 101: National Geographic
Cartoon overview of tsunami:
2 interactives of 2004 tsunami:
See 1st chapters of America’s Tsunami: Are We Next?
How Stuff Works.com
2004 first waves:
How the 2004 tsunami happened:
2004 Plate shift:
2004 teletsunami, India:
Pacific Warning System:
Tsunami warning system:
Mega Tsunami:

36. Megatsunami videos Alaska Deep Impact Could RI be hit tomorrow?
La Palma, Canary Islands (no sound)

37. Seismic Waves (shallow) Period ≈ 20 seconds Period ≈ 20 minutes
Celerity (another name for speed)
C = L/T L = wavelength (m)
C = 1.25√L d = depth (m)
C = 1.56 T C = celerity (m/s)
C = √gd = 3.1√d T = period (s)
Wind Waves (deep)
Seismic Waves (shallow)
Period ≈ 20 seconds
Period ≈ 20 minutes
L to ≈ 600 m
L to ≈ 200 km
So C can reach 112 km/hr
So C can reach 760 km/hr