Page 256 - DK Children's Encyclopedia

Tides SEE ALSO

▸ ▸ Day and night
p.77

Tides are daily changes in the level of the sea on the ▸ ▸ Gravity p.125
coast. They are mainly caused by the moon’s gravity, ▸ ▸ Moon p.171
which is an invisible force that pulls on the Earth. When ▸ ▸ Oceans and seas

the water is high up the coast, it is called high tide, and p.187
when it falls it is low tide. ▸ ▸ Seashore p.220
▸ ▸ Sun p.247

Low tide High tide
When the pull of the moon is weak, water levels When the pull of the moon is strong, water levels
fall and the tide goes out. rise and the tide comes in.

The moon and tides A high tide happens
The moon pulls the Earth’s around the parts of Earth Living between tides
closest to the moon.
oceans on the side facing it. The part of the coast that is covered up and
This makes sea levels rise, Earth then uncovered between the tides is called the
creating a high tide. Because intertidal zone. Many living things are found
here. They have to be tough to cope with
the Earth turns, tides rise battering waves at high tide, and air
and fall as parts of Earth Moon and sunlight at low tide.
turn toward and then away Mussels live on
from the moon. rocks. They shut
their shells when
the tide is out.
High tides happen Low tide occurs
on both sides of the where the moon’s
Earth at the same time. pull is at its weakest.

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