Environmental Earth Science

NAME:                                                                                                                                                    DATE:

Questions for the video "Waves, Beaches and Coasts" from The Earth Revealed Series (Annenberg/CPB). Read through these questions before the video, answer what you can during the video, and then share your answers after the video.

Definition: Waves are a mostly vertical movement of water that transfers energy across the surface of the water.

1. Most waves get their energy from:

2. Coastlines are the result of the interaction between:

3. When a wave approaches the beach, it's not the water itself that is moving, it is:

4. Describe one of the two analogies used in the video for the way that energy moves in waves.

5. Draw a diagram that shows how water particles move as a wave passes them:

6. What is the wave base?

7. What is the wavelength?

8. The depth of the wave base is about equal to _____________ the wavelength.

9. Breaking waves occur where the water is shallower than the __________________ , resulting in friction that causes the wave to get higher as the wavelength decreases.

10. A tsunami can travel at _______________ with a wavelength of _______________ . This results in stirring up _______________ even on the floor of the deep ocean.

Process: The energy of the wave is transferred to the shore when the wave hits, causing changes in the shoreline.

11. Refraction, or bending of waves, happens when:

12. Waves are refracted ________________ headlands (the parts of the land that stick out into the sea), which

________________ their force on the headlands, but waves are spread out in bays, decreasing their force.

13. Waves simultaneously ______________ the headlands, while _________________ the bays of uneven shorelines.

14. Most beach sand comes from:

15. The action of waves creates _____________ currents, which move and deposit to form:

16. In summer, beaches become:

17. In winter, the force of waves causes beaches to:

18. How do dams along rivers inland from the coast affect beaches?

19. How do seawalls affect beaches?

20. When people build structures along beaches, they ________________ the movement and deposition of sand that created the beach.

21. How do scientists study the effects of structures along the coast?

Definition: Tides are a rise and fall of sea level that occurs twice each day.

22. How do the Moon and Sun cause tides?

Definition: Spring tides are very high and low tides that occur twice each month when the Sun, Earth and Moon are aligned.

23. Most coastal destruction occurs when a storm surge comes ashore during:

24. The natural melting of glaciers since the last Ice Age, and from greenhouse gases from fossil fuels, may result in how much of a rise in sea level?

25. This rise in sea level would be enough to:

Not in video:

26. Rip currents occur where water from longshore currents returns out to sea, and if caught in one, a swimmer should swim parallel to shore until out of the current, not against the current. Diagram this:

HOMEWORK:

1. Finish video questions AND