Ocean Tides
Tides
• Changes in the level of ocean water during the
•
course of a day
The ocean levels reaches a high and low level
twice a day
High and Low Tides
• High tide – Water is pushed
•
up onto the shore
Low tide – 6 hours later
when water is pulled away
from shore
What causes the tides?
• The pull of gravity between Earth, the moon, and
•
•
the sun
Water in the oceans form a bulge on the side of
Earth facing the moon.
While on the other side (away from the moon), a
bulge forms because the water is thrown outward
Causes of tides
• Water in the oceans tries to travel away
from Earth’s orbit, but Earth’s gravity
keeps the water from flying off into space.
Spring Tides
• Spring tides occur during the full moon and
•
the new moon
The high tides are very high and the low tides
are very low
Neap Tides
• Neap tides occur during first and third quarter
•
•
moons
There is a small difference between high and
low tides.
The high tides are not as high and the low tides
are not as low.