Tidal Movements

Tides: the rise and fall of sea levels caused by the combined effects of the gravitational forces exerted by the Moon and the Sun and rotation of the Earth.

What causes tides?Gravitational pull from the moon and sun

How many tides in 24 hours?2 high tides and 2 low tides

Excess water is called a “dome”

Ebb: low flow of water

Flood: high flow of water

High tide: maximum flow of water on a beach

Low tide: minimal flow of water on a beach

Time between high and low tides = a “rest”

Peak of a high or low tide is a “slack”, not changing.

Different types of tides

Different types of tides

Spring tide: lunar and solar domes coincide.Higher than a high tide,or lower than a low tide.

Different types of tides

Neap tide: high tide is lower than normal.Low tide is higher than normal

Science Textbook

• Using the Earth Science Textbooks (Orange), open to Pages 492 – 496.

• Read through the text and write a paragraph in your journal explaining why and how tidal movements occur on your EQ#4 page.

• Textbooks can be checked out from NW library. • Classroom textbooks need to stay in the

classroom.