The regular and periodic fall and rise of the ocean water is called tides. The rising of water level is known as high tide or flood tide. The falling of water level is known as low tide or ebb tide. The difference between the high tide and low tide is called tidal range or range of tide.
Types of Tides:
There are different types of tides. The important types of tides are as follows:
1. Spring tides: Spring tides occur when the earth, sun and moon are more or less in a straight line. This happens on a full moon day. When the earth is between the sun and the moon or on a new moon day, when the moon is between the sun and the earth. The combined pull of the sun and moon on the earth is very great, and it produces very high tides and very low tides. Such tides are called spring tides.
2. Neap Tides: When the earth, sun and moon are not in a straight line, the sun and the moon are not exerting combined force.
3. So, the gravitational pull is much less. At half moon, the force exerted is the minimum. On the ocean water. Consequently the high tides are not very high and the low tides are not very low. They are called “Neap tides”.
