LET`S TALK ABOUT THE EARTHS TIDES...

Moon Phases...

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Refresher Activity...• What do we remember about the Phases of the Moon? • Fill in the Worksheet – Moon phases – you can discuss the

with your neighbours.

Moving On...• Tides – Movie Clip – “The Mysteries of Earths Tides.”

By:

http://www.youtube.com/watch?v=aN2RM5wa1ek&feature=related

Earth`s Tides...What are Tides?• Tides are the alternating rise and fall in sea level with and are produced by the gravitational attraction of the moon and the sun.• Have a look at the picture below, it is the same Harbour at two different times of the day. High Tide Low Tide

High Tide Low Tide

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How does the Phases of the Moon effect the Tides?• The gravitational attraction of the moon causes the oceans to bulge out in the direction of the moon. • Another bulge occurs on the opposite side, since the Earth is also being pulled toward the moon.• Ocean levels fluctuate daily as the sun, moon and earth interact. • As the moon travels around the earth and as they, together, travel around the sun, the combined gravitational forces cause the world's oceans to rise and fall. • Since the earth is rotating while this is happening, two tides occur each day.

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Are there names for the Tides?

• Yes there are, for this lesson we are only going to focus on two:

Spring tides Neap tides

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Spring Tide...

What is a Spring Tide?

• Spring tides are especially strong tides (they do not have anything to do with the season Spring). • They occur when the Earth, the Sun and the Moon are in a

line. • The gravitational forces of the Moon and the Sun both

contribute to the tides. • Spring tides occur during the full moon and the new moon.• Activity: Tides Worksheet – Spring Tide

Supplied by;:http://www.happisburgh.org.uk/gallery/ronjames/Spring_Tide_Looking_SE.jpg

Spring Tide...

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Neap Tide...

What is a Neap Tide?

• Neap tides are especially weak tides. • They occur when the gravitational

forces of the Moon and the Sun are perpendicular to one another (with respect to the Earth). • Neap tides occur during

quarter moons.• Activity:

Tides Worksheet – Neap tide

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Neap Tide...

Supplied by; http://www.physicalgeography.net/fundamentals/8r.html

Conclusion...

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Group Activity...Mini Tide Experts• Class divides into four groups• Each group will be given a different Moon Phase• Each phase refers to a different Earth Tide

Objective• Design a poster of your moon phase and how it influences

Tides on Earth.• Short presentation to the class.

Resources Available• Poster/butchers paper• Marker pens• Worksheet notes – Moon Phases and Tides

References:• National Oceanic and Atmospheric Administration. (2008). Tides and water levels. Retrieved from: http://oceanservice.noaa.gov/education/kits/tides/welcome.html

• Climate Science from the Southeast Pacific. (2008). Tides of the ocean. Retrieved from: http://www.windows.ucar.edu/tour/link=/earth/Water/ocean_tides.html&cd=falsel&portal=vocals&edu=mid

• Ignite Learning. (2009). The Mysteries of Earths Tides. Retrieved from: http://www.youtube.com/watch?v=aN2RM5wa1ek&feature=related