OCEANS

By: Seymour Simon

Tides

• The rise and fall of the water in the ocean.

• High tide and low tide each happen two times a day.

• Tides are caused by gravity from the sun and the moon.

• There are different types of tides.

Spring Tides• The biggest tides – caused when the sun

and the moon are lined up with the Earth.

Neap Tides• The smallest tides – caused when the

sun and the moon are perpendicular to each other.

The Bay of Fundy

• The Bay of Fundy has the largest difference between high and low tide in the world!!

High tide

Mid tide

Low tide

Waves

• Waves can be caused by wind or by underwater earthquakes.

• When they are caused by underwater earthquakes, they are called a tsunami (su-NAH-mee).

• One of the most devastating tsunamis occurred in December of last year in the Indian Ocean.

Tsunami area

Tsunami waves

A tsunami is caused by an underwater earthquake. The earthquake causes a gigantic movement of water. This water moves through the ocean until it hits land.

Click here to see an animation of the waves from the December 2004 tsunami in Asia.

Tsunami damage

before after

Tsunami damage

before after

Tsunami damage

before after

Tsunami damage

before

after

Waves• Waves can also be formed by the wind.• Waves are the wind’s energy. Only the energy

moves forward, the water only moves in a circle.• The water ends up where it started (look at blue

dots)

Largest wave• The largest wave on record is 112

feet high. This is the height of a 10-story building!!!

Credits• http://www.bim.ie/templates/tides.asp?node_id=416• http://www.amazon.com/exec/obidos/tg/detail/-/

0688154786/qid=1127745845/sr=2-1/ref=pd_bbs_b_2_1/104-8136935-6923145?v=glance&s=books

• http://www.thehopewellrocks.com/• http://www.elite.net/~thehalls/maasdam2.html• http://www.digitalglobe.com/tsunami_gallery.html• http://www.noaanews.noaa.gov/video/tsunami-

worldpropagation2004.mov• http://geology.com/articles/tsunami-map.shtml• http://www.mapsofworld.com/world-news/clickable-

south-asia-map.html• http://www.kettering.edu/~drussell/Demos/waves/

wavemotion.html