Rachel BladonCHAPTER ONE
Oceans of the World
There are five oceans, and they cover about 70 percent of Earth. Oceans and their seashores are different all around the world. On the Arctic Ocean and the Southern Ocean, there's a lot of ice in winter. In warm tropical oceans, you can find colorful coral reefs, where very many plants, fish, and other animals live.
An ocean is always moving because of waves, currents, and tides. When the wind blows over the water, it makes waves. Currents are large amounts of warm or cold water that move around the ocean. An ocean also moves up the seashore and back again two times a day. These movements are called tides.
Living in the ocean is very different to living on land. Ocean plants and animals have special ways of breathing, eating, moving, and keeping safe.
The blue whale is the biggest animal in the world. It can be more than 30 meters long! It moves well in the ocean because the water holds it up.