1 / 37

Ocean Waves and Tides

Ocean Waves and Tides. Waves. A Wave is a rhythmic movement that carries energy through matter or space. In oceans, waves move through seawater. Waves. Caused by : Wind Earthquakes Gravitational force of the Moon and Sun. Parts of a Wave. Crest – highest point of a wave

rruss
Download Presentation

Ocean Waves and Tides

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Ocean Waves and Tides

  2. Waves • A Wave is a rhythmicmovement that carries energy through matter or space. • In oceans, waves move through seawater

  3. Waves Caused by: • Wind • Earthquakes • Gravitational force of the Moon and Sun.

  4. Parts of a Wave • Crest – highest point of a wave • Trough – lowest point of a wave • Wave Height – vertical distance between the crest and the trough • Wavelength – horizontal distance between two crests or two troughs

  5. Wavelength Crest Wave Height Still Water Trough Wave Parts

  6. Wave Formations • Form when energy is transferred from a source to the ocean water • Most common from WIND

  7. Wave Movement • When a wave passes through the ocean, individual water molecules move up and down but they do not move forward or backward. • Water does NOT travel with waves

  8. Wave Movement • When a wave breaks against the shore, the crest outruns the trough and the crest collapses. • Called a breaker. • In this case, water does move forward and backward.

  9. Wave energy • Wind keeps adding more energy to waves • WIND SPEED: • -Wave period is time between 2 wave crests or 2 wave troughs • -Speed of wave= wave length/wave period

  10. Waves reaching Shore • Most waves reach shore and transfer energy to beach

  11. Why Waves Break • The ocean floor slows the bottom of the wave, yet the top is moving at original speed • Breaker is when wave’s crest crash on shore

  12. Waves Caused by Wind • When wind blows across a body of water, friction causes the water to move along with the wind. • Wave Height depends on – • Wind speed • Distance over which the wind blows • Length of time the wind blows

  13. Tides • The rise and fall in sea level is called a tide. • Caused by a giant wave. • One low-tide/high-tide cycle takes about 12 hrs and 25 min. • Tidal range is the difference in ocean level between high-tide and low-tide

  14. What is the Tidal Range? • HT = 30 ft, LT = 20 ft • HT = 20 ft, LT = 12 ft • HT = 50 ft, LT = 20 ft

  15. Tidal Range • The tidal range is the difference between the level of the ocean at high tide and low tide.

  16. Why Tides Happen • Moon’s gravity pulls on every particle of Earth • Moon’s pull decrease with increase in distance • Areas closer to the moon have stronger pull • Liquids are pulled more easily by gravity

  17. Where Tides Happen • Area of ocean that directly faces moon is pulled most • Area furthest from moon has little effect from moon’s pull • Ocean water bulges toward moon

  18. Gravitational Effect of the Moon • Two big bulges of water form on the Earth: • one directly under the moon • another on the exact opposite side • As the Earth spins, the bulges follow the moon.

  19. High tides and Low tides • High tide- bulges that form as a result of moon—Ocean level is higher than normal • Low tide- water is pulled toward opposite area where high tide is occurring • Each day usually has 2 high tides and 2 low tides

  20. Timing of Tide • Moon revolves around earth slower than earth rotates • Takes 24 hours 50 min to rotate to face the moon again • High tides and low tides happen 50 minutes later each day

  21. Tidal Variations • Sun has gravitational pull but far, when sun and moon pull together- greater tide • Spring Tides • Earth, Moon, and Sun are lined up • High Tides are higher and Low Tides are lower than normal • During new moon and full moon

  22. Spring TIDES

  23. Neap Tides • Earth, Moon, and Sun form right angles • High Tides are lower and Low Tides are higher than normal • During different phases of moon

  24. NEAP Tides • Neap tides are especially weak tides. • Moon & Sun are perpendicular to each other. • Moon & the Sun’s gravity cancel each other out.

  25. Mont St. Michel • A great example of tidal surge is the castle Mont St. Michel in France. • The tides surrounding the “Mount” can vary by 14 meters between high and low tides, and move in as rapidly as 1 meter a second. • The “Mount” is connected to the mainland by a thin natural land bridge, which before modernization was covered by the sea at high tide, and revealed during the low tide.

  26. The End

More Related