Tides Objectives and outcomes: 1- I will be able to describe and explain the formation of tides. 2- I can explain the difference between high tides, neap tides and the tidal range.

What are tides? High Tides Tides are the periodic rise and fall in the level of the sea and are caused by the gravitational pull of the sun and the moon. The moon has the greatest influence because it is nearer.

The moon pulls water towards it creating high tides and there is a compensatory bulge on the other side of the earth. The area between the two bulges the tides are at their lowest.

As the moon orbits the earth the high tide follows it As the moon orbits the earth the high tide follows it. Twice in a lunar month when the sun-moon and earth are in a straight line, the tide raising force is the strongest. This produces the highest monthly tidal range

Neap Tides Twice a month the sun and moon are positioned at 90o to each other in relation to the earth. This alignment gives the lowest monthly tidal range, or neap time.

Tidal range The tidal range can be a significant factor in the development of a coastline. Along the coastline of the Mediterranean sea tidal ranges are low. This restricts wave action to a narrow width of the coastal zone. In parts of the UK tidal ranges are high, this gives a wide zone of wave attack, resulting in the formation of wave cut platforms.