53 Along the Coast-Mid

Along the Coast FOCUS Question How does the ocean change the land along a coast?

Where Land and Water Meet A coast is the edge of land. It is where land meets the ocean. Another name for that edge is a coastline. Each coastline is different. The land can be steep, flat, rocky, or sandy. Wowser Earth has more than 571,000 kilometers (355,000 mi.) of coastline. That's more than the distance from Earth to the Moon!

Never the Same Coastlines are always changing. Wind makes waves on the ocean. Waves are very strong and are always moving. They move the sand and rocks on the shore. Waves change a coastline.

Rocky Coasts In some places. the land at the coastline is very steep. Those coastlines have rocky cliffs. Over time, big waves cause pieces to break off the cliffs. Sometimes the broken cliffs are in the shape of arches or sea stacks. Do You Know? Waves can make holes in rocks. Some seabirds use the holes for nests.

Some coastlines don't have cliffs. But the land is still rocky. When the tide comes in, water fills holes between the rocks. When the tide goes out, some water stays behind. These holes full of water are called tide pools.

Life in Tide Pools Many animals live in coastal tide pools. For some animals. the calm water in the tide pools is safer than the open sea. Some pools are home to crabs and sea urchins. Sometimes small fish live in tide pools, too. You might even see an octopus!