Geography: Waves and Tides

Does the water level always change?

Even when the sea is calm and flat, the water level is always changing.

What happens if the backwash has more energy than the uprush?

If the backwash has more energy than the uprush, it will drag pebbles and sand away with it. (This happens with high, steep waves.)

What happens if the uprush has more energy than the backwash?

If the uprush has more energy than the backwash, it will carry material onto the land and leave it there. (This happens with low, flat waves.)

Why does the water level always change?

It changes because of the moon. As the moon travels around Earth, it attracts the sea and pulls it upwards.

Does the Sun affect the tides?

The Sun helps too- but it is much further away, so its pull is not as strong.

What is the fetch of a wave?

The length of water that the wind blows over is called the fetch.

What gives us tides?

The rise and fall of the sea gives us tides.

What causes waves?

Waves are caused by the wind dragging on the surface of the water.