Tides and Tsunami

Tides are also important physical forces in our ocean Gravitational interactions between the sun, moon and earth are the primary causes of tides

What is a tide? A tide is the periodic rise and fall of a body of water due to gravitational interactions between the sun, moon and Earth Different positions of the sun and moon causes two different types of tides: spring tides and neap tides Tides play an important role in the life cycle of many marine organisms

What causes tides? The gravitational pull of the sun and the moon causes “bulges” on Earth that move as we rotate Gravitational pull “Bulge” of Earth Sun Earth Moon Teacher’s Note: The slide labels the gravitational pull and bulge of the Earth as you advance the slide.

Different types of tide - Spring tides Sun Earth Moon Spring tides occur when the sun and moon are in a straight line The tidal range is typically highest during spring tides

Different types of tide – Neap tides Earth Neap (every 15 days ) tides occur when the sun and moon form a right angle with Earth Why is the moon’s pull greater than the sun’s? Teacher’s Note: Even though the sun is larger than the moon, the moon’s pull is always greater because the moon is much closer to the earth. Sun Moon

Moon Gravitational field lines from the moon

High tide Low tide

Tsunami