Exploring Tide Pools

Exploring Tide Pools

What Are Tide Pools? The tide is the rising and falling of the ocean where it meets the land. The tide rises and falls twice each day. In some areas, little pools of seawater are left behind when the tide goes out. These are tide pools. Most tide pools are found in low areas along rocky shorelines. You might also find small tide pools on sandy beaches. Any place along the shoreline that traps water creates a tide pool.

What Causes Tides? The tides are caused by the force of gravity. The sun and moon have strong gravity that pulls on Earth. This gravity pulls on both land and water. But only the water can move in response to gravity. When the sun and moon pull on Earth, they pull the ocean water into two mounds.

The rotation, or spin, of Earth causes the rising and falling of the tides. As land areas move into and out of where the water is in mounds, the tides slowly rise and fall. Since Earth makes one full rotation each day, there are two high tides and two low tides every 24 hours. The moon also moves around Earth, and this movement affects the tides. Twice each month, the moon and sun line up. They pull on the ocean water together. Their combined gravity causes higher mounds of water, creating the highest and lowest tides of the month. These tides are called spring tides. At other times, the sun and moon pull against each other. At these times, the high tides are not as high, and the low tides are not as low. These are called neap (neep) tides.

The Intertidal Zone The area along the shore between high tide and low tide is the intertidal zone. This area is covered by seawater during high tide and exposed to air during low tide. The area closest to the sea is only exposed to the air during the very lowest tides. The area farthest from the sea is only covered by water during the highest tides. Different creatures live in different parts of the intertidal zone, depending on whether they need air or water.

What Is Life tike in a Tide Pool? Tide pools are full of sea life. You can see these creatures when the tide goes out. Usually, the more places there are for animals to hide or attach themselves, the more animals you will find in a tide pool. The tide pools with the most animals usually occur in rocky areas. The material the animals live in or attach themselves to is called the substrate. In tide pools, the substrate is usually rocks or sand.