Everything you ever wanted to know about Earth's oceans in one pocket-size, easy-to-read guide. Nearly 97 percent of our planet's water is held in the vast oceans that teem with life. This incredible book on oceans for children aged 9-12 uses stunning images and clear artworks to reveal the secrets of this underwater world. Within the pages of this book you'll discover the range of organisms--from colossal whales to microscopic plankton--that call the oceans home. Find out about tidal pools, salt marshes, coral reefs, ocean floor ridges, and the other natural features of these vast bodies of water. Learn how the oceans formed, what causes tsunamis, how tidal waves are used to generate electricity, and what marine experts are doing to save our oceans.